fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48
  49 #include "ext4.h"
  50 #include "ext4_extents.h"       /* Needed for trace points definition */
  51 #include "ext4_jbd2.h"
  52 #include "xattr.h"
  53 #include "acl.h"
  54 #include "mballoc.h"
  55 #include "fsmap.h"
  56
  57 #define CREATE_TRACE_POINTS
  58 #include <trace/events/ext4.h>
  59
  60 static struct ext4_lazy_init *ext4_li_info;
  61 static struct mutex ext4_li_mtx;
  62 static struct ratelimit_state ext4_mount_msg_ratelimit;
  63
  64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  65                              unsigned long journal_devnum);
  66 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  67 static int ext4_commit_super(struct super_block *sb, int sync);
  68 static void ext4_mark_recovery_complete(struct super_block *sb,
  69                                         struct ext4_super_block *es);
  70 static void ext4_clear_journal_err(struct super_block *sb,
  71                                    struct ext4_super_block *es);
  72 static int ext4_sync_fs(struct super_block *sb, int wait);
  73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  75 static int ext4_unfreeze(struct super_block *sb);
  76 static int ext4_freeze(struct super_block *sb);
  77 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  78                        const char *dev_name, void *data);
  79 static inline int ext2_feature_set_ok(struct super_block *sb);
  80 static inline int ext3_feature_set_ok(struct super_block *sb);
  81 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87
  88 /*
  89  * Lock ordering
  90  *
  91  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  92  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  93  *
  94  * page fault path:
  95  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  96  *   page lock -> i_data_sem (rw)
  97  *
  98  * buffered write path:
  99  * sb_start_write -> i_mutex -> mmap_sem
 100  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 101  *   i_data_sem (rw)
 102  *
 103  * truncate:
 104  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 106  *   i_data_sem (rw)
 107  *
 108  * direct IO:
 109  * sb_start_write -> i_mutex -> mmap_sem
 110  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 111  *
 112  * writepages:
 113  * transaction start -> page lock(s) -> i_data_sem (rw)
 114  */
 115
 116 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 117 static struct file_system_type ext2_fs_type = {
 118         .owner          = THIS_MODULE,
 119         .name           = "ext2",
 120         .mount          = ext4_mount,
 121         .kill_sb        = kill_block_super,
 122         .fs_flags       = FS_REQUIRES_DEV,
 123 };
 124 MODULE_ALIAS_FS("ext2");
 125 MODULE_ALIAS("ext2");
 126 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 127 #else
 128 #define IS_EXT2_SB(sb) (0)
 129 #endif
 130
 131
 132 static struct file_system_type ext3_fs_type = {
 133         .owner          = THIS_MODULE,
 134         .name           = "ext3",
 135         .mount          = ext4_mount,
 136         .kill_sb        = kill_block_super,
 137         .fs_flags       = FS_REQUIRES_DEV,
 138 };
 139 MODULE_ALIAS_FS("ext3");
 140 MODULE_ALIAS("ext3");
 141 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 142
 143 static int ext4_verify_csum_type(struct super_block *sb,
 144                                  struct ext4_super_block *es)
 145 {
 146         if (!ext4_has_feature_metadata_csum(sb))
 147                 return 1;
 148
 149         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 150 }
 151
 152 static __le32 ext4_superblock_csum(struct super_block *sb,
 153                                    struct ext4_super_block *es)
 154 {
 155         struct ext4_sb_info *sbi = EXT4_SB(sb);
 156         int offset = offsetof(struct ext4_super_block, s_checksum);
 157         __u32 csum;
 158
 159         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 160
 161         return cpu_to_le32(csum);
 162 }
 163
 164 static int ext4_superblock_csum_verify(struct super_block *sb,
 165                                        struct ext4_super_block *es)
 166 {
 167         if (!ext4_has_metadata_csum(sb))
 168                 return 1;
 169
 170         return es->s_checksum == ext4_superblock_csum(sb, es);
 171 }
 172
 173 void ext4_superblock_csum_set(struct super_block *sb)
 174 {
 175         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 176
 177         if (!ext4_has_metadata_csum(sb))
 178                 return;
 179
 180         es->s_checksum = ext4_superblock_csum(sb, es);
 181 }
 182
 183 void *ext4_kvmalloc(size_t size, gfp_t flags)
 184 {
 185         void *ret;
 186
 187         ret = kmalloc(size, flags | __GFP_NOWARN);
 188         if (!ret)
 189                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 190         return ret;
 191 }
 192
 193 void *ext4_kvzalloc(size_t size, gfp_t flags)
 194 {
 195         void *ret;
 196
 197         ret = kzalloc(size, flags | __GFP_NOWARN);
 198         if (!ret)
 199                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 200         return ret;
 201 }
 202
 203 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 204                                struct ext4_group_desc *bg)
 205 {
 206         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 207                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 208                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 209 }
 210
 211 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 212                                struct ext4_group_desc *bg)
 213 {
 214         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 215                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 216                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 217 }
 218
 219 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 220                               struct ext4_group_desc *bg)
 221 {
 222         return le32_to_cpu(bg->bg_inode_table_lo) |
 223                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 224                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 225 }
 226
 227 __u32 ext4_free_group_clusters(struct super_block *sb,
 228                                struct ext4_group_desc *bg)
 229 {
 230         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 231                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 232                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 233 }
 234
 235 __u32 ext4_free_inodes_count(struct super_block *sb,
 236                               struct ext4_group_desc *bg)
 237 {
 238         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 239                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 240                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 241 }
 242
 243 __u32 ext4_used_dirs_count(struct super_block *sb,
 244                               struct ext4_group_desc *bg)
 245 {
 246         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 247                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 248                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 249 }
 250
 251 __u32 ext4_itable_unused_count(struct super_block *sb,
 252                               struct ext4_group_desc *bg)
 253 {
 254         return le16_to_cpu(bg->bg_itable_unused_lo) |
 255                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 256                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 257 }
 258
 259 void ext4_block_bitmap_set(struct super_block *sb,
 260                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 261 {
 262         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 263         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 264                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 265 }
 266
 267 void ext4_inode_bitmap_set(struct super_block *sb,
 268                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 269 {
 270         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 271         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 272                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 273 }
 274
 275 void ext4_inode_table_set(struct super_block *sb,
 276                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 277 {
 278         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 279         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 280                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 281 }
 282
 283 void ext4_free_group_clusters_set(struct super_block *sb,
 284                                   struct ext4_group_desc *bg, __u32 count)
 285 {
 286         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 287         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 288                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 289 }
 290
 291 void ext4_free_inodes_set(struct super_block *sb,
 292                           struct ext4_group_desc *bg, __u32 count)
 293 {
 294         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 295         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 296                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 297 }
 298
 299 void ext4_used_dirs_set(struct super_block *sb,
 300                           struct ext4_group_desc *bg, __u32 count)
 301 {
 302         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 303         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 304                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 305 }
 306
 307 void ext4_itable_unused_set(struct super_block *sb,
 308                           struct ext4_group_desc *bg, __u32 count)
 309 {
 310         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 311         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 312                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 313 }
 314
 315
 316 static void __save_error_info(struct super_block *sb, const char *func,
 317                             unsigned int line)
 318 {
 319         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 320
 321         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 322         if (bdev_read_only(sb->s_bdev))
 323                 return;
 324         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 325         es->s_last_error_time = cpu_to_le32(get_seconds());
 326         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 327         es->s_last_error_line = cpu_to_le32(line);
 328         if (!es->s_first_error_time) {
 329                 es->s_first_error_time = es->s_last_error_time;
 330                 strncpy(es->s_first_error_func, func,
 331                         sizeof(es->s_first_error_func));
 332                 es->s_first_error_line = cpu_to_le32(line);
 333                 es->s_first_error_ino = es->s_last_error_ino;
 334                 es->s_first_error_block = es->s_last_error_block;
 335         }
 336         /*
 337          * Start the daily error reporting function if it hasn't been
 338          * started already
 339          */
 340         if (!es->s_error_count)
 341                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 342         le32_add_cpu(&es->s_error_count, 1);
 343 }
 344
 345 static void save_error_info(struct super_block *sb, const char *func,
 346                             unsigned int line)
 347 {
 348         __save_error_info(sb, func, line);
 349         ext4_commit_super(sb, 1);
 350 }
 351
 352 /*
 353  * The del_gendisk() function uninitializes the disk-specific data
 354  * structures, including the bdi structure, without telling anyone
 355  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 356  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 357  * This is a kludge to prevent these oops until we can put in a proper
 358  * hook in del_gendisk() to inform the VFS and file system layers.
 359  */
 360 static int block_device_ejected(struct super_block *sb)
 361 {
 362         struct inode *bd_inode = sb->s_bdev->bd_inode;
 363         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 364
 365         return bdi->dev == NULL;
 366 }
 367
 368 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 369 {
 370         struct super_block              *sb = journal->j_private;
 371         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 372         int                             error = is_journal_aborted(journal);
 373         struct ext4_journal_cb_entry    *jce;
 374
 375         BUG_ON(txn->t_state == T_FINISHED);
 376
 377         ext4_process_freed_data(sb, txn->t_tid);
 378
 379         spin_lock(&sbi->s_md_lock);
 380         while (!list_empty(&txn->t_private_list)) {
 381                 jce = list_entry(txn->t_private_list.next,
 382                                  struct ext4_journal_cb_entry, jce_list);
 383                 list_del_init(&jce->jce_list);
 384                 spin_unlock(&sbi->s_md_lock);
 385                 jce->jce_func(sb, jce, error);
 386                 spin_lock(&sbi->s_md_lock);
 387         }
 388         spin_unlock(&sbi->s_md_lock);
 389 }
 390
 391 /* Deal with the reporting of failure conditions on a filesystem such as
 392  * inconsistencies detected or read IO failures.
 393  *
 394  * On ext2, we can store the error state of the filesystem in the
 395  * superblock.  That is not possible on ext4, because we may have other
 396  * write ordering constraints on the superblock which prevent us from
 397  * writing it out straight away; and given that the journal is about to
 398  * be aborted, we can't rely on the current, or future, transactions to
 399  * write out the superblock safely.
 400  *
 401  * We'll just use the jbd2_journal_abort() error code to record an error in
 402  * the journal instead.  On recovery, the journal will complain about
 403  * that error until we've noted it down and cleared it.
 404  */
 405
 406 static void ext4_handle_error(struct super_block *sb)
 407 {
 408         if (test_opt(sb, WARN_ON_ERROR))
 409                 WARN_ON_ONCE(1);
 410
 411         if (sb_rdonly(sb))
 412                 return;
 413
 414         if (!test_opt(sb, ERRORS_CONT)) {
 415                 journal_t *journal = EXT4_SB(sb)->s_journal;
 416
 417                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 418                 if (journal)
 419                         jbd2_journal_abort(journal, -EIO);
 420         }
 421         if (test_opt(sb, ERRORS_RO)) {
 422                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 423                 /*
 424                  * Make sure updated value of ->s_mount_flags will be visible
 425                  * before ->s_flags update
 426                  */
 427                 smp_wmb();
 428                 sb->s_flags |= SB_RDONLY;
 429         }
 430         if (test_opt(sb, ERRORS_PANIC)) {
 431                 if (EXT4_SB(sb)->s_journal &&
 432                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 433                         return;
 434                 panic("EXT4-fs (device %s): panic forced after error\n",
 435                         sb->s_id);
 436         }
 437 }
 438
 439 #define ext4_error_ratelimit(sb)                                        \
 440                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 441                              "EXT4-fs error")
 442
 443 void __ext4_error(struct super_block *sb, const char *function,
 444                   unsigned int line, const char *fmt, ...)
 445 {
 446         struct va_format vaf;
 447         va_list args;
 448
 449         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 450                 return;
 451
 452         trace_ext4_error(sb, function, line);
 453         if (ext4_error_ratelimit(sb)) {
 454                 va_start(args, fmt);
 455                 vaf.fmt = fmt;
 456                 vaf.va = &args;
 457                 printk(KERN_CRIT
 458                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 459                        sb->s_id, function, line, current->comm, &vaf);
 460                 va_end(args);
 461         }
 462         save_error_info(sb, function, line);
 463         ext4_handle_error(sb);
 464 }
 465
 466 void __ext4_error_inode(struct inode *inode, const char *function,
 467                         unsigned int line, ext4_fsblk_t block,
 468                         const char *fmt, ...)
 469 {
 470         va_list args;
 471         struct va_format vaf;
 472         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 473
 474         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 475                 return;
 476
 477         trace_ext4_error(inode->i_sb, function, line);
 478         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 479         es->s_last_error_block = cpu_to_le64(block);
 480         if (ext4_error_ratelimit(inode->i_sb)) {
 481                 va_start(args, fmt);
 482                 vaf.fmt = fmt;
 483                 vaf.va = &args;
 484                 if (block)
 485                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 486                                "inode #%lu: block %llu: comm %s: %pV\n",
 487                                inode->i_sb->s_id, function, line, inode->i_ino,
 488                                block, current->comm, &vaf);
 489                 else
 490                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 491                                "inode #%lu: comm %s: %pV\n",
 492                                inode->i_sb->s_id, function, line, inode->i_ino,
 493                                current->comm, &vaf);
 494                 va_end(args);
 495         }
 496         save_error_info(inode->i_sb, function, line);
 497         ext4_handle_error(inode->i_sb);
 498 }
 499
 500 void __ext4_error_file(struct file *file, const char *function,
 501                        unsigned int line, ext4_fsblk_t block,
 502                        const char *fmt, ...)
 503 {
 504         va_list args;
 505         struct va_format vaf;
 506         struct ext4_super_block *es;
 507         struct inode *inode = file_inode(file);
 508         char pathname[80], *path;
 509
 510         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 511                 return;
 512
 513         trace_ext4_error(inode->i_sb, function, line);
 514         es = EXT4_SB(inode->i_sb)->s_es;
 515         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 516         if (ext4_error_ratelimit(inode->i_sb)) {
 517                 path = file_path(file, pathname, sizeof(pathname));
 518                 if (IS_ERR(path))
 519                         path = "(unknown)";
 520                 va_start(args, fmt);
 521                 vaf.fmt = fmt;
 522                 vaf.va = &args;
 523                 if (block)
 524                         printk(KERN_CRIT
 525                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 526                                "block %llu: comm %s: path %s: %pV\n",
 527                                inode->i_sb->s_id, function, line, inode->i_ino,
 528                                block, current->comm, path, &vaf);
 529                 else
 530                         printk(KERN_CRIT
 531                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 532                                "comm %s: path %s: %pV\n",
 533                                inode->i_sb->s_id, function, line, inode->i_ino,
 534                                current->comm, path, &vaf);
 535                 va_end(args);
 536         }
 537         save_error_info(inode->i_sb, function, line);
 538         ext4_handle_error(inode->i_sb);
 539 }
 540
 541 const char *ext4_decode_error(struct super_block *sb, int errno,
 542                               char nbuf[16])
 543 {
 544         char *errstr = NULL;
 545
 546         switch (errno) {
 547         case -EFSCORRUPTED:
 548                 errstr = "Corrupt filesystem";
 549                 break;
 550         case -EFSBADCRC:
 551                 errstr = "Filesystem failed CRC";
 552                 break;
 553         case -EIO:
 554                 errstr = "IO failure";
 555                 break;
 556         case -ENOMEM:
 557                 errstr = "Out of memory";
 558                 break;
 559         case -EROFS:
 560                 if (!sb || (EXT4_SB(sb)->s_journal &&
 561                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 562                         errstr = "Journal has aborted";
 563                 else
 564                         errstr = "Readonly filesystem";
 565                 break;
 566         default:
 567                 /* If the caller passed in an extra buffer for unknown
 568                  * errors, textualise them now.  Else we just return
 569                  * NULL. */
 570                 if (nbuf) {
 571                         /* Check for truncated error codes... */
 572                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 573                                 errstr = nbuf;
 574                 }
 575                 break;
 576         }
 577
 578         return errstr;
 579 }
 580
 581 /* __ext4_std_error decodes expected errors from journaling functions
 582  * automatically and invokes the appropriate error response.  */
 583
 584 void __ext4_std_error(struct super_block *sb, const char *function,
 585                       unsigned int line, int errno)
 586 {
 587         char nbuf[16];
 588         const char *errstr;
 589
 590         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 591                 return;
 592
 593         /* Special case: if the error is EROFS, and we're not already
 594          * inside a transaction, then there's really no point in logging
 595          * an error. */
 596         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 597                 return;
 598
 599         if (ext4_error_ratelimit(sb)) {
 600                 errstr = ext4_decode_error(sb, errno, nbuf);
 601                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 602                        sb->s_id, function, line, errstr);
 603         }
 604
 605         save_error_info(sb, function, line);
 606         ext4_handle_error(sb);
 607 }
 608
 609 /*
 610  * ext4_abort is a much stronger failure handler than ext4_error.  The
 611  * abort function may be used to deal with unrecoverable failures such
 612  * as journal IO errors or ENOMEM at a critical moment in log management.
 613  *
 614  * We unconditionally force the filesystem into an ABORT|READONLY state,
 615  * unless the error response on the fs has been set to panic in which
 616  * case we take the easy way out and panic immediately.
 617  */
 618
 619 void __ext4_abort(struct super_block *sb, const char *function,
 620                 unsigned int line, const char *fmt, ...)
 621 {
 622         struct va_format vaf;
 623         va_list args;
 624
 625         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 626                 return;
 627
 628         save_error_info(sb, function, line);
 629         va_start(args, fmt);
 630         vaf.fmt = fmt;
 631         vaf.va = &args;
 632         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 633                sb->s_id, function, line, &vaf);
 634         va_end(args);
 635
 636         if (sb_rdonly(sb) == 0) {
 637                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 638                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 639                 /*
 640                  * Make sure updated value of ->s_mount_flags will be visible
 641                  * before ->s_flags update
 642                  */
 643                 smp_wmb();
 644                 sb->s_flags |= SB_RDONLY;
 645                 if (EXT4_SB(sb)->s_journal)
 646                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 647                 save_error_info(sb, function, line);
 648         }
 649         if (test_opt(sb, ERRORS_PANIC)) {
 650                 if (EXT4_SB(sb)->s_journal &&
 651                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 652                         return;
 653                 panic("EXT4-fs panic from previous error\n");
 654         }
 655 }
 656
 657 void __ext4_msg(struct super_block *sb,
 658                 const char *prefix, const char *fmt, ...)
 659 {
 660         struct va_format vaf;
 661         va_list args;
 662
 663         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 664                 return;
 665
 666         va_start(args, fmt);
 667         vaf.fmt = fmt;
 668         vaf.va = &args;
 669         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 670         va_end(args);
 671 }
 672
 673 #define ext4_warning_ratelimit(sb)                                      \
 674                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 675                              "EXT4-fs warning")
 676
 677 void __ext4_warning(struct super_block *sb, const char *function,
 678                     unsigned int line, const char *fmt, ...)
 679 {
 680         struct va_format vaf;
 681         va_list args;
 682
 683         if (!ext4_warning_ratelimit(sb))
 684                 return;
 685
 686         va_start(args, fmt);
 687         vaf.fmt = fmt;
 688         vaf.va = &args;
 689         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 690                sb->s_id, function, line, &vaf);
 691         va_end(args);
 692 }
 693
 694 void __ext4_warning_inode(const struct inode *inode, const char *function,
 695                           unsigned int line, const char *fmt, ...)
 696 {
 697         struct va_format vaf;
 698         va_list args;
 699
 700         if (!ext4_warning_ratelimit(inode->i_sb))
 701                 return;
 702
 703         va_start(args, fmt);
 704         vaf.fmt = fmt;
 705         vaf.va = &args;
 706         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 707                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 708                function, line, inode->i_ino, current->comm, &vaf);
 709         va_end(args);
 710 }
 711
 712 void __ext4_grp_locked_error(const char *function, unsigned int line,
 713                              struct super_block *sb, ext4_group_t grp,
 714                              unsigned long ino, ext4_fsblk_t block,
 715                              const char *fmt, ...)
 716 __releases(bitlock)
 717 __acquires(bitlock)
 718 {
 719         struct va_format vaf;
 720         va_list args;
 721         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 722
 723         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 724                 return;
 725
 726         trace_ext4_error(sb, function, line);
 727         es->s_last_error_ino = cpu_to_le32(ino);
 728         es->s_last_error_block = cpu_to_le64(block);
 729         __save_error_info(sb, function, line);
 730
 731         if (ext4_error_ratelimit(sb)) {
 732                 va_start(args, fmt);
 733                 vaf.fmt = fmt;
 734                 vaf.va = &args;
 735                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 736                        sb->s_id, function, line, grp);
 737                 if (ino)
 738                         printk(KERN_CONT "inode %lu: ", ino);
 739                 if (block)
 740                         printk(KERN_CONT "block %llu:",
 741                                (unsigned long long) block);
 742                 printk(KERN_CONT "%pV\n", &vaf);
 743                 va_end(args);
 744         }
 745
 746         if (test_opt(sb, WARN_ON_ERROR))
 747                 WARN_ON_ONCE(1);
 748
 749         if (test_opt(sb, ERRORS_CONT)) {
 750                 ext4_commit_super(sb, 0);
 751                 return;
 752         }
 753
 754         ext4_unlock_group(sb, grp);
 755         ext4_commit_super(sb, 1);
 756         ext4_handle_error(sb);
 757         /*
 758          * We only get here in the ERRORS_RO case; relocking the group
 759          * may be dangerous, but nothing bad will happen since the
 760          * filesystem will have already been marked read/only and the
 761          * journal has been aborted.  We return 1 as a hint to callers
 762          * who might what to use the return value from
 763          * ext4_grp_locked_error() to distinguish between the
 764          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 765          * aggressively from the ext4 function in question, with a
 766          * more appropriate error code.
 767          */
 768         ext4_lock_group(sb, grp);
 769         return;
 770 }
 771
 772 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 773                                      ext4_group_t group,
 774                                      unsigned int flags)
 775 {
 776         struct ext4_sb_info *sbi = EXT4_SB(sb);
 777         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 778         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 779
 780         if ((flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) &&
 781             !EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) {
 782                 percpu_counter_sub(&sbi->s_freeclusters_counter,
 783                                         grp->bb_free);
 784                 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 785                         &grp->bb_state);
 786         }
 787
 788         if ((flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) &&
 789             !EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
 790                 if (gdp) {
 791                         int count;
 792
 793                         count = ext4_free_inodes_count(sb, gdp);
 794                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 795                                            count);
 796                 }
 797                 set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 798                         &grp->bb_state);
 799         }
 800 }
 801
 802 void ext4_update_dynamic_rev(struct super_block *sb)
 803 {
 804         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 805
 806         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 807                 return;
 808
 809         ext4_warning(sb,
 810                      "updating to rev %d because of new feature flag, "
 811                      "running e2fsck is recommended",
 812                      EXT4_DYNAMIC_REV);
 813
 814         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 815         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 816         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 817         /* leave es->s_feature_*compat flags alone */
 818         /* es->s_uuid will be set by e2fsck if empty */
 819
 820         /*
 821          * The rest of the superblock fields should be zero, and if not it
 822          * means they are likely already in use, so leave them alone.  We
 823          * can leave it up to e2fsck to clean up any inconsistencies there.
 824          */
 825 }
 826
 827 /*
 828  * Open the external journal device
 829  */
 830 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 831 {
 832         struct block_device *bdev;
 833         char b[BDEVNAME_SIZE];
 834
 835         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 836         if (IS_ERR(bdev))
 837                 goto fail;
 838         return bdev;
 839
 840 fail:
 841         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 842                         __bdevname(dev, b), PTR_ERR(bdev));
 843         return NULL;
 844 }
 845
 846 /*
 847  * Release the journal device
 848  */
 849 static void ext4_blkdev_put(struct block_device *bdev)
 850 {
 851         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 852 }
 853
 854 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 855 {
 856         struct block_device *bdev;
 857         bdev = sbi->journal_bdev;
 858         if (bdev) {
 859                 ext4_blkdev_put(bdev);
 860                 sbi->journal_bdev = NULL;
 861         }
 862 }
 863
 864 static inline struct inode *orphan_list_entry(struct list_head *l)
 865 {
 866         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 867 }
 868
 869 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 870 {
 871         struct list_head *l;
 872
 873         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 874                  le32_to_cpu(sbi->s_es->s_last_orphan));
 875
 876         printk(KERN_ERR "sb_info orphan list:\n");
 877         list_for_each(l, &sbi->s_orphan) {
 878                 struct inode *inode = orphan_list_entry(l);
 879                 printk(KERN_ERR "  "
 880                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 881                        inode->i_sb->s_id, inode->i_ino, inode,
 882                        inode->i_mode, inode->i_nlink,
 883                        NEXT_ORPHAN(inode));
 884         }
 885 }
 886
 887 #ifdef CONFIG_QUOTA
 888 static int ext4_quota_off(struct super_block *sb, int type);
 889
 890 static inline void ext4_quota_off_umount(struct super_block *sb)
 891 {
 892         int type;
 893
 894         /* Use our quota_off function to clear inode flags etc. */
 895         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 896                 ext4_quota_off(sb, type);
 897 }
 898 #else
 899 static inline void ext4_quota_off_umount(struct super_block *sb)
 900 {
 901 }
 902 #endif
 903
 904 static void ext4_put_super(struct super_block *sb)
 905 {
 906         struct ext4_sb_info *sbi = EXT4_SB(sb);
 907         struct ext4_super_block *es = sbi->s_es;
 908         int aborted = 0;
 909         int i, err;
 910
 911         ext4_unregister_li_request(sb);
 912         ext4_quota_off_umount(sb);
 913
 914         destroy_workqueue(sbi->rsv_conversion_wq);
 915
 916         if (sbi->s_journal) {
 917                 aborted = is_journal_aborted(sbi->s_journal);
 918                 err = jbd2_journal_destroy(sbi->s_journal);
 919                 sbi->s_journal = NULL;
 920                 if ((err < 0) && !aborted)
 921                         ext4_abort(sb, "Couldn't clean up the journal");
 922         }
 923
 924         ext4_unregister_sysfs(sb);
 925         ext4_es_unregister_shrinker(sbi);
 926         del_timer_sync(&sbi->s_err_report);
 927         ext4_release_system_zone(sb);
 928         ext4_mb_release(sb);
 929         ext4_ext_release(sb);
 930
 931         if (!sb_rdonly(sb) && !aborted) {
 932                 ext4_clear_feature_journal_needs_recovery(sb);
 933                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 934         }
 935         if (!sb_rdonly(sb))
 936                 ext4_commit_super(sb, 1);
 937
 938         for (i = 0; i < sbi->s_gdb_count; i++)
 939                 brelse(sbi->s_group_desc[i]);
 940         kvfree(sbi->s_group_desc);
 941         kvfree(sbi->s_flex_groups);
 942         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 943         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 944         percpu_counter_destroy(&sbi->s_dirs_counter);
 945         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 946         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
 947 #ifdef CONFIG_QUOTA
 948         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 949                 kfree(sbi->s_qf_names[i]);
 950 #endif
 951
 952         /* Debugging code just in case the in-memory inode orphan list
 953          * isn't empty.  The on-disk one can be non-empty if we've
 954          * detected an error and taken the fs readonly, but the
 955          * in-memory list had better be clean by this point. */
 956         if (!list_empty(&sbi->s_orphan))
 957                 dump_orphan_list(sb, sbi);
 958         J_ASSERT(list_empty(&sbi->s_orphan));
 959
 960         sync_blockdev(sb->s_bdev);
 961         invalidate_bdev(sb->s_bdev);
 962         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 963                 /*
 964                  * Invalidate the journal device's buffers.  We don't want them
 965                  * floating about in memory - the physical journal device may
 966                  * hotswapped, and it breaks the `ro-after' testing code.
 967                  */
 968                 sync_blockdev(sbi->journal_bdev);
 969                 invalidate_bdev(sbi->journal_bdev);
 970                 ext4_blkdev_remove(sbi);
 971         }
 972         if (sbi->s_ea_inode_cache) {
 973                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
 974                 sbi->s_ea_inode_cache = NULL;
 975         }
 976         if (sbi->s_ea_block_cache) {
 977                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
 978                 sbi->s_ea_block_cache = NULL;
 979         }
 980         if (sbi->s_mmp_tsk)
 981                 kthread_stop(sbi->s_mmp_tsk);
 982         brelse(sbi->s_sbh);
 983         sb->s_fs_info = NULL;
 984         /*
 985          * Now that we are completely done shutting down the
 986          * superblock, we need to actually destroy the kobject.
 987          */
 988         kobject_put(&sbi->s_kobj);
 989         wait_for_completion(&sbi->s_kobj_unregister);
 990         if (sbi->s_chksum_driver)
 991                 crypto_free_shash(sbi->s_chksum_driver);
 992         kfree(sbi->s_blockgroup_lock);
 993         fs_put_dax(sbi->s_daxdev);
 994         kfree(sbi);
 995 }
 996
 997 static struct kmem_cache *ext4_inode_cachep;
 998
 999 /*
1000  * Called inside transaction, so use GFP_NOFS
1001  */
1002 static struct inode *ext4_alloc_inode(struct super_block *sb)
1003 {
1004         struct ext4_inode_info *ei;
1005
1006         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1007         if (!ei)
1008                 return NULL;
1009
1010         inode_set_iversion(&ei->vfs_inode, 1);
1011         spin_lock_init(&ei->i_raw_lock);
1012         INIT_LIST_HEAD(&ei->i_prealloc_list);
1013         spin_lock_init(&ei->i_prealloc_lock);
1014         ext4_es_init_tree(&ei->i_es_tree);
1015         rwlock_init(&ei->i_es_lock);
1016         INIT_LIST_HEAD(&ei->i_es_list);
1017         ei->i_es_all_nr = 0;
1018         ei->i_es_shk_nr = 0;
1019         ei->i_es_shrink_lblk = 0;
1020         ei->i_reserved_data_blocks = 0;
1021         ei->i_da_metadata_calc_len = 0;
1022         ei->i_da_metadata_calc_last_lblock = 0;
1023         spin_lock_init(&(ei->i_block_reservation_lock));
1024 #ifdef CONFIG_QUOTA
1025         ei->i_reserved_quota = 0;
1026         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1027 #endif
1028         ei->jinode = NULL;
1029         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1030         spin_lock_init(&ei->i_completed_io_lock);
1031         ei->i_sync_tid = 0;
1032         ei->i_datasync_tid = 0;
1033         atomic_set(&ei->i_unwritten, 0);
1034         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1035         return &ei->vfs_inode;
1036 }
1037
1038 static int ext4_drop_inode(struct inode *inode)
1039 {
1040         int drop = generic_drop_inode(inode);
1041
1042         trace_ext4_drop_inode(inode, drop);
1043         return drop;
1044 }
1045
1046 static void ext4_i_callback(struct rcu_head *head)
1047 {
1048         struct inode *inode = container_of(head, struct inode, i_rcu);
1049         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1050 }
1051
1052 static void ext4_destroy_inode(struct inode *inode)
1053 {
1054         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1055                 ext4_msg(inode->i_sb, KERN_ERR,
1056                          "Inode %lu (%p): orphan list check failed!",
1057                          inode->i_ino, EXT4_I(inode));
1058                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1059                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1060                                 true);
1061                 dump_stack();
1062         }
1063         call_rcu(&inode->i_rcu, ext4_i_callback);
1064 }
1065
1066 static void init_once(void *foo)
1067 {
1068         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1069
1070         INIT_LIST_HEAD(&ei->i_orphan);
1071         init_rwsem(&ei->xattr_sem);
1072         init_rwsem(&ei->i_data_sem);
1073         init_rwsem(&ei->i_mmap_sem);
1074         inode_init_once(&ei->vfs_inode);
1075 }
1076
1077 static int __init init_inodecache(void)
1078 {
1079         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1080                                 sizeof(struct ext4_inode_info), 0,
1081                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1082                                         SLAB_ACCOUNT),
1083                                 offsetof(struct ext4_inode_info, i_data),
1084                                 sizeof_field(struct ext4_inode_info, i_data),
1085                                 init_once);
1086         if (ext4_inode_cachep == NULL)
1087                 return -ENOMEM;
1088         return 0;
1089 }
1090
1091 static void destroy_inodecache(void)
1092 {
1093         /*
1094          * Make sure all delayed rcu free inodes are flushed before we
1095          * destroy cache.
1096          */
1097         rcu_barrier();
1098         kmem_cache_destroy(ext4_inode_cachep);
1099 }
1100
1101 void ext4_clear_inode(struct inode *inode)
1102 {
1103         invalidate_inode_buffers(inode);
1104         clear_inode(inode);
1105         dquot_drop(inode);
1106         ext4_discard_preallocations(inode);
1107         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1108         if (EXT4_I(inode)->jinode) {
1109                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1110                                                EXT4_I(inode)->jinode);
1111                 jbd2_free_inode(EXT4_I(inode)->jinode);
1112                 EXT4_I(inode)->jinode = NULL;
1113         }
1114         fscrypt_put_encryption_info(inode);
1115 }
1116
1117 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1118                                         u64 ino, u32 generation)
1119 {
1120         struct inode *inode;
1121
1122         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1123                 return ERR_PTR(-ESTALE);
1124         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1125                 return ERR_PTR(-ESTALE);
1126
1127         /* iget isn't really right if the inode is currently unallocated!!
1128          *
1129          * ext4_read_inode will return a bad_inode if the inode had been
1130          * deleted, so we should be safe.
1131          *
1132          * Currently we don't know the generation for parent directory, so
1133          * a generation of 0 means "accept any"
1134          */
1135         inode = ext4_iget_normal(sb, ino);
1136         if (IS_ERR(inode))
1137                 return ERR_CAST(inode);
1138         if (generation && inode->i_generation != generation) {
1139                 iput(inode);
1140                 return ERR_PTR(-ESTALE);
1141         }
1142
1143         return inode;
1144 }
1145
1146 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1147                                         int fh_len, int fh_type)
1148 {
1149         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1150                                     ext4_nfs_get_inode);
1151 }
1152
1153 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1154                                         int fh_len, int fh_type)
1155 {
1156         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1157                                     ext4_nfs_get_inode);
1158 }
1159
1160 /*
1161  * Try to release metadata pages (indirect blocks, directories) which are
1162  * mapped via the block device.  Since these pages could have journal heads
1163  * which would prevent try_to_free_buffers() from freeing them, we must use
1164  * jbd2 layer's try_to_free_buffers() function to release them.
1165  */
1166 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1167                                  gfp_t wait)
1168 {
1169         journal_t *journal = EXT4_SB(sb)->s_journal;
1170
1171         WARN_ON(PageChecked(page));
1172         if (!page_has_buffers(page))
1173                 return 0;
1174         if (journal)
1175                 return jbd2_journal_try_to_free_buffers(journal, page,
1176                                                 wait & ~__GFP_DIRECT_RECLAIM);
1177         return try_to_free_buffers(page);
1178 }
1179
1180 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1181 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1182 {
1183         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1184                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1185 }
1186
1187 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1188                                                         void *fs_data)
1189 {
1190         handle_t *handle = fs_data;
1191         int res, res2, credits, retries = 0;
1192
1193         /*
1194          * Encrypting the root directory is not allowed because e2fsck expects
1195          * lost+found to exist and be unencrypted, and encrypting the root
1196          * directory would imply encrypting the lost+found directory as well as
1197          * the filename "lost+found" itself.
1198          */
1199         if (inode->i_ino == EXT4_ROOT_INO)
1200                 return -EPERM;
1201
1202         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1203                 return -EINVAL;
1204
1205         res = ext4_convert_inline_data(inode);
1206         if (res)
1207                 return res;
1208
1209         /*
1210          * If a journal handle was specified, then the encryption context is
1211          * being set on a new inode via inheritance and is part of a larger
1212          * transaction to create the inode.  Otherwise the encryption context is
1213          * being set on an existing inode in its own transaction.  Only in the
1214          * latter case should the "retry on ENOSPC" logic be used.
1215          */
1216
1217         if (handle) {
1218                 res = ext4_xattr_set_handle(handle, inode,
1219                                             EXT4_XATTR_INDEX_ENCRYPTION,
1220                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1221                                             ctx, len, 0);
1222                 if (!res) {
1223                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1224                         ext4_clear_inode_state(inode,
1225                                         EXT4_STATE_MAY_INLINE_DATA);
1226                         /*
1227                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1228                          * S_DAX may be disabled
1229                          */
1230                         ext4_set_inode_flags(inode);
1231                 }
1232                 return res;
1233         }
1234
1235         res = dquot_initialize(inode);
1236         if (res)
1237                 return res;
1238 retry:
1239         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1240                                      &credits);
1241         if (res)
1242                 return res;
1243
1244         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1245         if (IS_ERR(handle))
1246                 return PTR_ERR(handle);
1247
1248         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1249                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1250                                     ctx, len, 0);
1251         if (!res) {
1252                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1253                 /*
1254                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1255                  * S_DAX may be disabled
1256                  */
1257                 ext4_set_inode_flags(inode);
1258                 res = ext4_mark_inode_dirty(handle, inode);
1259                 if (res)
1260                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1261         }
1262         res2 = ext4_journal_stop(handle);
1263
1264         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1265                 goto retry;
1266         if (!res)
1267                 res = res2;
1268         return res;
1269 }
1270
1271 static bool ext4_dummy_context(struct inode *inode)
1272 {
1273         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1274 }
1275
1276 static unsigned ext4_max_namelen(struct inode *inode)
1277 {
1278         return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
1279                 EXT4_NAME_LEN;
1280 }
1281
1282 static const struct fscrypt_operations ext4_cryptops = {
1283         .key_prefix             = "ext4:",
1284         .get_context            = ext4_get_context,
1285         .set_context            = ext4_set_context,
1286         .dummy_context          = ext4_dummy_context,
1287         .empty_dir              = ext4_empty_dir,
1288         .max_namelen            = ext4_max_namelen,
1289 };
1290 #endif
1291
1292 #ifdef CONFIG_QUOTA
1293 static const char * const quotatypes[] = INITQFNAMES;
1294 #define QTYPE2NAME(t) (quotatypes[t])
1295
1296 static int ext4_write_dquot(struct dquot *dquot);
1297 static int ext4_acquire_dquot(struct dquot *dquot);
1298 static int ext4_release_dquot(struct dquot *dquot);
1299 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1300 static int ext4_write_info(struct super_block *sb, int type);
1301 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1302                          const struct path *path);
1303 static int ext4_quota_on_mount(struct super_block *sb, int type);
1304 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1305                                size_t len, loff_t off);
1306 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1307                                 const char *data, size_t len, loff_t off);
1308 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1309                              unsigned int flags);
1310 static int ext4_enable_quotas(struct super_block *sb);
1311 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1312
1313 static struct dquot **ext4_get_dquots(struct inode *inode)
1314 {
1315         return EXT4_I(inode)->i_dquot;
1316 }
1317
1318 static const struct dquot_operations ext4_quota_operations = {
1319         .get_reserved_space     = ext4_get_reserved_space,
1320         .write_dquot            = ext4_write_dquot,
1321         .acquire_dquot          = ext4_acquire_dquot,
1322         .release_dquot          = ext4_release_dquot,
1323         .mark_dirty             = ext4_mark_dquot_dirty,
1324         .write_info             = ext4_write_info,
1325         .alloc_dquot            = dquot_alloc,
1326         .destroy_dquot          = dquot_destroy,
1327         .get_projid             = ext4_get_projid,
1328         .get_inode_usage        = ext4_get_inode_usage,
1329         .get_next_id            = ext4_get_next_id,
1330 };
1331
1332 static const struct quotactl_ops ext4_qctl_operations = {
1333         .quota_on       = ext4_quota_on,
1334         .quota_off      = ext4_quota_off,
1335         .quota_sync     = dquot_quota_sync,
1336         .get_state      = dquot_get_state,
1337         .set_info       = dquot_set_dqinfo,
1338         .get_dqblk      = dquot_get_dqblk,
1339         .set_dqblk      = dquot_set_dqblk,
1340         .get_nextdqblk  = dquot_get_next_dqblk,
1341 };
1342 #endif
1343
1344 static const struct super_operations ext4_sops = {
1345         .alloc_inode    = ext4_alloc_inode,
1346         .destroy_inode  = ext4_destroy_inode,
1347         .write_inode    = ext4_write_inode,
1348         .dirty_inode    = ext4_dirty_inode,
1349         .drop_inode     = ext4_drop_inode,
1350         .evict_inode    = ext4_evict_inode,
1351         .put_super      = ext4_put_super,
1352         .sync_fs        = ext4_sync_fs,
1353         .freeze_fs      = ext4_freeze,
1354         .unfreeze_fs    = ext4_unfreeze,
1355         .statfs         = ext4_statfs,
1356         .remount_fs     = ext4_remount,
1357         .show_options   = ext4_show_options,
1358 #ifdef CONFIG_QUOTA
1359         .quota_read     = ext4_quota_read,
1360         .quota_write    = ext4_quota_write,
1361         .get_dquots     = ext4_get_dquots,
1362 #endif
1363         .bdev_try_to_free_page = bdev_try_to_free_page,
1364 };
1365
1366 static const struct export_operations ext4_export_ops = {
1367         .fh_to_dentry = ext4_fh_to_dentry,
1368         .fh_to_parent = ext4_fh_to_parent,
1369         .get_parent = ext4_get_parent,
1370 };
1371
1372 enum {
1373         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1374         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1375         Opt_nouid32, Opt_debug, Opt_removed,
1376         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1377         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1378         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1379         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1380         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1381         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1382         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1383         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1384         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1385         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1386         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1387         Opt_nowarn_on_error, Opt_mblk_io_submit,
1388         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1389         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1390         Opt_inode_readahead_blks, Opt_journal_ioprio,
1391         Opt_dioread_nolock, Opt_dioread_lock,
1392         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1393         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1394 };
1395
1396 static const match_table_t tokens = {
1397         {Opt_bsd_df, "bsddf"},
1398         {Opt_minix_df, "minixdf"},
1399         {Opt_grpid, "grpid"},
1400         {Opt_grpid, "bsdgroups"},
1401         {Opt_nogrpid, "nogrpid"},
1402         {Opt_nogrpid, "sysvgroups"},
1403         {Opt_resgid, "resgid=%u"},
1404         {Opt_resuid, "resuid=%u"},
1405         {Opt_sb, "sb=%u"},
1406         {Opt_err_cont, "errors=continue"},
1407         {Opt_err_panic, "errors=panic"},
1408         {Opt_err_ro, "errors=remount-ro"},
1409         {Opt_nouid32, "nouid32"},
1410         {Opt_debug, "debug"},
1411         {Opt_removed, "oldalloc"},
1412         {Opt_removed, "orlov"},
1413         {Opt_user_xattr, "user_xattr"},
1414         {Opt_nouser_xattr, "nouser_xattr"},
1415         {Opt_acl, "acl"},
1416         {Opt_noacl, "noacl"},
1417         {Opt_noload, "norecovery"},
1418         {Opt_noload, "noload"},
1419         {Opt_removed, "nobh"},
1420         {Opt_removed, "bh"},
1421         {Opt_commit, "commit=%u"},
1422         {Opt_min_batch_time, "min_batch_time=%u"},
1423         {Opt_max_batch_time, "max_batch_time=%u"},
1424         {Opt_journal_dev, "journal_dev=%u"},
1425         {Opt_journal_path, "journal_path=%s"},
1426         {Opt_journal_checksum, "journal_checksum"},
1427         {Opt_nojournal_checksum, "nojournal_checksum"},
1428         {Opt_journal_async_commit, "journal_async_commit"},
1429         {Opt_abort, "abort"},
1430         {Opt_data_journal, "data=journal"},
1431         {Opt_data_ordered, "data=ordered"},
1432         {Opt_data_writeback, "data=writeback"},
1433         {Opt_data_err_abort, "data_err=abort"},
1434         {Opt_data_err_ignore, "data_err=ignore"},
1435         {Opt_offusrjquota, "usrjquota="},
1436         {Opt_usrjquota, "usrjquota=%s"},
1437         {Opt_offgrpjquota, "grpjquota="},
1438         {Opt_grpjquota, "grpjquota=%s"},
1439         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1440         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1441         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1442         {Opt_grpquota, "grpquota"},
1443         {Opt_noquota, "noquota"},
1444         {Opt_quota, "quota"},
1445         {Opt_usrquota, "usrquota"},
1446         {Opt_prjquota, "prjquota"},
1447         {Opt_barrier, "barrier=%u"},
1448         {Opt_barrier, "barrier"},
1449         {Opt_nobarrier, "nobarrier"},
1450         {Opt_i_version, "i_version"},
1451         {Opt_dax, "dax"},
1452         {Opt_stripe, "stripe=%u"},
1453         {Opt_delalloc, "delalloc"},
1454         {Opt_warn_on_error, "warn_on_error"},
1455         {Opt_nowarn_on_error, "nowarn_on_error"},
1456         {Opt_lazytime, "lazytime"},
1457         {Opt_nolazytime, "nolazytime"},
1458         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1459         {Opt_nodelalloc, "nodelalloc"},
1460         {Opt_removed, "mblk_io_submit"},
1461         {Opt_removed, "nomblk_io_submit"},
1462         {Opt_block_validity, "block_validity"},
1463         {Opt_noblock_validity, "noblock_validity"},
1464         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1465         {Opt_journal_ioprio, "journal_ioprio=%u"},
1466         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1467         {Opt_auto_da_alloc, "auto_da_alloc"},
1468         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1469         {Opt_dioread_nolock, "dioread_nolock"},
1470         {Opt_dioread_lock, "dioread_lock"},
1471         {Opt_discard, "discard"},
1472         {Opt_nodiscard, "nodiscard"},
1473         {Opt_init_itable, "init_itable=%u"},
1474         {Opt_init_itable, "init_itable"},
1475         {Opt_noinit_itable, "noinit_itable"},
1476         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1477         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1478         {Opt_nombcache, "nombcache"},
1479         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1480         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1481         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1482         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1483         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1484         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1485         {Opt_err, NULL},
1486 };
1487
1488 static ext4_fsblk_t get_sb_block(void **data)
1489 {
1490         ext4_fsblk_t    sb_block;
1491         char            *options = (char *) *data;
1492
1493         if (!options || strncmp(options, "sb=", 3) != 0)
1494                 return 1;       /* Default location */
1495
1496         options += 3;
1497         /* TODO: use simple_strtoll with >32bit ext4 */
1498         sb_block = simple_strtoul(options, &options, 0);
1499         if (*options && *options != ',') {
1500                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1501                        (char *) *data);
1502                 return 1;
1503         }
1504         if (*options == ',')
1505                 options++;
1506         *data = (void *) options;
1507
1508         return sb_block;
1509 }
1510
1511 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1512 static const char deprecated_msg[] =
1513         "Mount option \"%s\" will be removed by %s\n"
1514         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1515
1516 #ifdef CONFIG_QUOTA
1517 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1518 {
1519         struct ext4_sb_info *sbi = EXT4_SB(sb);
1520         char *qname;
1521         int ret = -1;
1522
1523         if (sb_any_quota_loaded(sb) &&
1524                 !sbi->s_qf_names[qtype]) {
1525                 ext4_msg(sb, KERN_ERR,
1526                         "Cannot change journaled "
1527                         "quota options when quota turned on");
1528                 return -1;
1529         }
1530         if (ext4_has_feature_quota(sb)) {
1531                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1532                          "ignored when QUOTA feature is enabled");
1533                 return 1;
1534         }
1535         qname = match_strdup(args);
1536         if (!qname) {
1537                 ext4_msg(sb, KERN_ERR,
1538                         "Not enough memory for storing quotafile name");
1539                 return -1;
1540         }
1541         if (sbi->s_qf_names[qtype]) {
1542                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1543                         ret = 1;
1544                 else
1545                         ext4_msg(sb, KERN_ERR,
1546                                  "%s quota file already specified",
1547                                  QTYPE2NAME(qtype));
1548                 goto errout;
1549         }
1550         if (strchr(qname, '/')) {
1551                 ext4_msg(sb, KERN_ERR,
1552                         "quotafile must be on filesystem root");
1553                 goto errout;
1554         }
1555         sbi->s_qf_names[qtype] = qname;
1556         set_opt(sb, QUOTA);
1557         return 1;
1558 errout:
1559         kfree(qname);
1560         return ret;
1561 }
1562
1563 static int clear_qf_name(struct super_block *sb, int qtype)
1564 {
1565
1566         struct ext4_sb_info *sbi = EXT4_SB(sb);
1567
1568         if (sb_any_quota_loaded(sb) &&
1569                 sbi->s_qf_names[qtype]) {
1570                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1571                         " when quota turned on");
1572                 return -1;
1573         }
1574         kfree(sbi->s_qf_names[qtype]);
1575         sbi->s_qf_names[qtype] = NULL;
1576         return 1;
1577 }
1578 #endif
1579
1580 #define MOPT_SET        0x0001
1581 #define MOPT_CLEAR      0x0002
1582 #define MOPT_NOSUPPORT  0x0004
1583 #define MOPT_EXPLICIT   0x0008
1584 #define MOPT_CLEAR_ERR  0x0010
1585 #define MOPT_GTE0       0x0020
1586 #ifdef CONFIG_QUOTA
1587 #define MOPT_Q          0
1588 #define MOPT_QFMT       0x0040
1589 #else
1590 #define MOPT_Q          MOPT_NOSUPPORT
1591 #define MOPT_QFMT       MOPT_NOSUPPORT
1592 #endif
1593 #define MOPT_DATAJ      0x0080
1594 #define MOPT_NO_EXT2    0x0100
1595 #define MOPT_NO_EXT3    0x0200
1596 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1597 #define MOPT_STRING     0x0400
1598
1599 static const struct mount_opts {
1600         int     token;
1601         int     mount_opt;
1602         int     flags;
1603 } ext4_mount_opts[] = {
1604         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1605         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1606         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1607         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1608         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1609         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1610         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1611          MOPT_EXT4_ONLY | MOPT_SET},
1612         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1613          MOPT_EXT4_ONLY | MOPT_CLEAR},
1614         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1615         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1616         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1617          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1618         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1619          MOPT_EXT4_ONLY | MOPT_CLEAR},
1620         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1621         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1622         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1623          MOPT_EXT4_ONLY | MOPT_CLEAR},
1624         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1625          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1626         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1627                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1628          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1629         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1630         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1631         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1632         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1633         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1634          MOPT_NO_EXT2},
1635         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1636          MOPT_NO_EXT2},
1637         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1638         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1639         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1640         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1641         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1642         {Opt_commit, 0, MOPT_GTE0},
1643         {Opt_max_batch_time, 0, MOPT_GTE0},
1644         {Opt_min_batch_time, 0, MOPT_GTE0},
1645         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1646         {Opt_init_itable, 0, MOPT_GTE0},
1647         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1648         {Opt_stripe, 0, MOPT_GTE0},
1649         {Opt_resuid, 0, MOPT_GTE0},
1650         {Opt_resgid, 0, MOPT_GTE0},
1651         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1652         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1653         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1654         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1655         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1656         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1657          MOPT_NO_EXT2 | MOPT_DATAJ},
1658         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1659         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1660 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1661         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1662         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1663 #else
1664         {Opt_acl, 0, MOPT_NOSUPPORT},
1665         {Opt_noacl, 0, MOPT_NOSUPPORT},
1666 #endif
1667         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1668         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1669         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1670         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1671         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1672                                                         MOPT_SET | MOPT_Q},
1673         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1674                                                         MOPT_SET | MOPT_Q},
1675         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1676                                                         MOPT_SET | MOPT_Q},
1677         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1678                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1679                                                         MOPT_CLEAR | MOPT_Q},
1680         {Opt_usrjquota, 0, MOPT_Q},
1681         {Opt_grpjquota, 0, MOPT_Q},
1682         {Opt_offusrjquota, 0, MOPT_Q},
1683         {Opt_offgrpjquota, 0, MOPT_Q},
1684         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1685         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1686         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1687         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1688         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1689         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1690         {Opt_err, 0, 0}
1691 };
1692
1693 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1694                             substring_t *args, unsigned long *journal_devnum,
1695                             unsigned int *journal_ioprio, int is_remount)
1696 {
1697         struct ext4_sb_info *sbi = EXT4_SB(sb);
1698         const struct mount_opts *m;
1699         kuid_t uid;
1700         kgid_t gid;
1701         int arg = 0;
1702
1703 #ifdef CONFIG_QUOTA
1704         if (token == Opt_usrjquota)
1705                 return set_qf_name(sb, USRQUOTA, &args[0]);
1706         else if (token == Opt_grpjquota)
1707                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1708         else if (token == Opt_offusrjquota)
1709                 return clear_qf_name(sb, USRQUOTA);
1710         else if (token == Opt_offgrpjquota)
1711                 return clear_qf_name(sb, GRPQUOTA);
1712 #endif
1713         switch (token) {
1714         case Opt_noacl:
1715         case Opt_nouser_xattr:
1716                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1717                 break;
1718         case Opt_sb:
1719                 return 1;       /* handled by get_sb_block() */
1720         case Opt_removed:
1721                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1722                 return 1;
1723         case Opt_abort:
1724                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1725                 return 1;
1726         case Opt_i_version:
1727                 sb->s_flags |= SB_I_VERSION;
1728                 return 1;
1729         case Opt_lazytime:
1730                 sb->s_flags |= SB_LAZYTIME;
1731                 return 1;
1732         case Opt_nolazytime:
1733                 sb->s_flags &= ~SB_LAZYTIME;
1734                 return 1;
1735         }
1736
1737         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1738                 if (token == m->token)
1739                         break;
1740
1741         if (m->token == Opt_err) {
1742                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1743                          "or missing value", opt);
1744                 return -1;
1745         }
1746
1747         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1748                 ext4_msg(sb, KERN_ERR,
1749                          "Mount option \"%s\" incompatible with ext2", opt);
1750                 return -1;
1751         }
1752         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1753                 ext4_msg(sb, KERN_ERR,
1754                          "Mount option \"%s\" incompatible with ext3", opt);
1755                 return -1;
1756         }
1757
1758         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1759                 return -1;
1760         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1761                 return -1;
1762         if (m->flags & MOPT_EXPLICIT) {
1763                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1764                         set_opt2(sb, EXPLICIT_DELALLOC);
1765                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1766                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1767                 } else
1768                         return -1;
1769         }
1770         if (m->flags & MOPT_CLEAR_ERR)
1771                 clear_opt(sb, ERRORS_MASK);
1772         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1773                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1774                          "options when quota turned on");
1775                 return -1;
1776         }
1777
1778         if (m->flags & MOPT_NOSUPPORT) {
1779                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1780         } else if (token == Opt_commit) {
1781                 if (arg == 0)
1782                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1783                 sbi->s_commit_interval = HZ * arg;
1784         } else if (token == Opt_debug_want_extra_isize) {
1785                 sbi->s_want_extra_isize = arg;
1786         } else if (token == Opt_max_batch_time) {
1787                 sbi->s_max_batch_time = arg;
1788         } else if (token == Opt_min_batch_time) {
1789                 sbi->s_min_batch_time = arg;
1790         } else if (token == Opt_inode_readahead_blks) {
1791                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1792                         ext4_msg(sb, KERN_ERR,
1793                                  "EXT4-fs: inode_readahead_blks must be "
1794                                  "0 or a power of 2 smaller than 2^31");
1795                         return -1;
1796                 }
1797                 sbi->s_inode_readahead_blks = arg;
1798         } else if (token == Opt_init_itable) {
1799                 set_opt(sb, INIT_INODE_TABLE);
1800                 if (!args->from)
1801                         arg = EXT4_DEF_LI_WAIT_MULT;
1802                 sbi->s_li_wait_mult = arg;
1803         } else if (token == Opt_max_dir_size_kb) {
1804                 sbi->s_max_dir_size_kb = arg;
1805         } else if (token == Opt_stripe) {
1806                 sbi->s_stripe = arg;
1807         } else if (token == Opt_resuid) {
1808                 uid = make_kuid(current_user_ns(), arg);
1809                 if (!uid_valid(uid)) {
1810                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1811                         return -1;
1812                 }
1813                 sbi->s_resuid = uid;
1814         } else if (token == Opt_resgid) {
1815                 gid = make_kgid(current_user_ns(), arg);
1816                 if (!gid_valid(gid)) {
1817                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1818                         return -1;
1819                 }
1820                 sbi->s_resgid = gid;
1821         } else if (token == Opt_journal_dev) {
1822                 if (is_remount) {
1823                         ext4_msg(sb, KERN_ERR,
1824                                  "Cannot specify journal on remount");
1825                         return -1;
1826                 }
1827                 *journal_devnum = arg;
1828         } else if (token == Opt_journal_path) {
1829                 char *journal_path;
1830                 struct inode *journal_inode;
1831                 struct path path;
1832                 int error;
1833
1834                 if (is_remount) {
1835                         ext4_msg(sb, KERN_ERR,
1836                                  "Cannot specify journal on remount");
1837                         return -1;
1838                 }
1839                 journal_path = match_strdup(&args[0]);
1840                 if (!journal_path) {
1841                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1842                                 "journal device string");
1843                         return -1;
1844                 }
1845
1846                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1847                 if (error) {
1848                         ext4_msg(sb, KERN_ERR, "error: could not find "
1849                                 "journal device path: error %d", error);
1850                         kfree(journal_path);
1851                         return -1;
1852                 }
1853
1854                 journal_inode = d_inode(path.dentry);
1855                 if (!S_ISBLK(journal_inode->i_mode)) {
1856                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1857                                 "is not a block device", journal_path);
1858                         path_put(&path);
1859                         kfree(journal_path);
1860                         return -1;
1861                 }
1862
1863                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1864                 path_put(&path);
1865                 kfree(journal_path);
1866         } else if (token == Opt_journal_ioprio) {
1867                 if (arg > 7) {
1868                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1869                                  " (must be 0-7)");
1870                         return -1;
1871                 }
1872                 *journal_ioprio =
1873                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1874         } else if (token == Opt_test_dummy_encryption) {
1875 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1876                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1877                 ext4_msg(sb, KERN_WARNING,
1878                          "Test dummy encryption mode enabled");
1879 #else
1880                 ext4_msg(sb, KERN_WARNING,
1881                          "Test dummy encryption mount option ignored");
1882 #endif
1883         } else if (m->flags & MOPT_DATAJ) {
1884                 if (is_remount) {
1885                         if (!sbi->s_journal)
1886                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1887                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1888                                 ext4_msg(sb, KERN_ERR,
1889                                          "Cannot change data mode on remount");
1890                                 return -1;
1891                         }
1892                 } else {
1893                         clear_opt(sb, DATA_FLAGS);
1894                         sbi->s_mount_opt |= m->mount_opt;
1895                 }
1896 #ifdef CONFIG_QUOTA
1897         } else if (m->flags & MOPT_QFMT) {
1898                 if (sb_any_quota_loaded(sb) &&
1899                     sbi->s_jquota_fmt != m->mount_opt) {
1900                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1901                                  "quota options when quota turned on");
1902                         return -1;
1903                 }
1904                 if (ext4_has_feature_quota(sb)) {
1905                         ext4_msg(sb, KERN_INFO,
1906                                  "Quota format mount options ignored "
1907                                  "when QUOTA feature is enabled");
1908                         return 1;
1909                 }
1910                 sbi->s_jquota_fmt = m->mount_opt;
1911 #endif
1912         } else if (token == Opt_dax) {
1913 #ifdef CONFIG_FS_DAX
1914                 ext4_msg(sb, KERN_WARNING,
1915                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1916                         sbi->s_mount_opt |= m->mount_opt;
1917 #else
1918                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1919                 return -1;
1920 #endif
1921         } else if (token == Opt_data_err_abort) {
1922                 sbi->s_mount_opt |= m->mount_opt;
1923         } else if (token == Opt_data_err_ignore) {
1924                 sbi->s_mount_opt &= ~m->mount_opt;
1925         } else {
1926                 if (!args->from)
1927                         arg = 1;
1928                 if (m->flags & MOPT_CLEAR)
1929                         arg = !arg;
1930                 else if (unlikely(!(m->flags & MOPT_SET))) {
1931                         ext4_msg(sb, KERN_WARNING,
1932                                  "buggy handling of option %s", opt);
1933                         WARN_ON(1);
1934                         return -1;
1935                 }
1936                 if (arg != 0)
1937                         sbi->s_mount_opt |= m->mount_opt;
1938                 else
1939                         sbi->s_mount_opt &= ~m->mount_opt;
1940         }
1941         return 1;
1942 }
1943
1944 static int parse_options(char *options, struct super_block *sb,
1945                          unsigned long *journal_devnum,
1946                          unsigned int *journal_ioprio,
1947                          int is_remount)
1948 {
1949         struct ext4_sb_info *sbi = EXT4_SB(sb);
1950         char *p;
1951         substring_t args[MAX_OPT_ARGS];
1952         int token;
1953
1954         if (!options)
1955                 return 1;
1956
1957         while ((p = strsep(&options, ",")) != NULL) {
1958                 if (!*p)
1959                         continue;
1960                 /*
1961                  * Initialize args struct so we know whether arg was
1962                  * found; some options take optional arguments.
1963                  */
1964                 args[0].to = args[0].from = NULL;
1965                 token = match_token(p, tokens, args);
1966                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1967                                      journal_ioprio, is_remount) < 0)
1968                         return 0;
1969         }
1970 #ifdef CONFIG_QUOTA
1971         /*
1972          * We do the test below only for project quotas. 'usrquota' and
1973          * 'grpquota' mount options are allowed even without quota feature
1974          * to support legacy quotas in quota files.
1975          */
1976         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
1977                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
1978                          "Cannot enable project quota enforcement.");
1979                 return 0;
1980         }
1981         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1982                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1983                         clear_opt(sb, USRQUOTA);
1984
1985                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1986                         clear_opt(sb, GRPQUOTA);
1987
1988                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1989                         ext4_msg(sb, KERN_ERR, "old and new quota "
1990                                         "format mixing");
1991                         return 0;
1992                 }
1993
1994                 if (!sbi->s_jquota_fmt) {
1995                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1996                                         "not specified");
1997                         return 0;
1998                 }
1999         }
2000 #endif
2001         if (test_opt(sb, DIOREAD_NOLOCK)) {
2002                 int blocksize =
2003                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2004
2005                 if (blocksize < PAGE_SIZE) {
2006                         ext4_msg(sb, KERN_ERR, "can't mount with "
2007                                  "dioread_nolock if block size != PAGE_SIZE");
2008                         return 0;
2009                 }
2010         }
2011         return 1;
2012 }
2013
2014 static inline void ext4_show_quota_options(struct seq_file *seq,
2015                                            struct super_block *sb)
2016 {
2017 #if defined(CONFIG_QUOTA)
2018         struct ext4_sb_info *sbi = EXT4_SB(sb);
2019
2020         if (sbi->s_jquota_fmt) {
2021                 char *fmtname = "";
2022
2023                 switch (sbi->s_jquota_fmt) {
2024                 case QFMT_VFS_OLD:
2025                         fmtname = "vfsold";
2026                         break;
2027                 case QFMT_VFS_V0:
2028                         fmtname = "vfsv0";
2029                         break;
2030                 case QFMT_VFS_V1:
2031                         fmtname = "vfsv1";
2032                         break;
2033                 }
2034                 seq_printf(seq, ",jqfmt=%s", fmtname);
2035         }
2036
2037         if (sbi->s_qf_names[USRQUOTA])
2038                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
2039
2040         if (sbi->s_qf_names[GRPQUOTA])
2041                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
2042 #endif
2043 }
2044
2045 static const char *token2str(int token)
2046 {
2047         const struct match_token *t;
2048
2049         for (t = tokens; t->token != Opt_err; t++)
2050                 if (t->token == token && !strchr(t->pattern, '='))
2051                         break;
2052         return t->pattern;
2053 }
2054
2055 /*
2056  * Show an option if
2057  *  - it's set to a non-default value OR
2058  *  - if the per-sb default is different from the global default
2059  */
2060 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2061                               int nodefs)
2062 {
2063         struct ext4_sb_info *sbi = EXT4_SB(sb);
2064         struct ext4_super_block *es = sbi->s_es;
2065         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2066         const struct mount_opts *m;
2067         char sep = nodefs ? '\n' : ',';
2068
2069 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2070 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2071
2072         if (sbi->s_sb_block != 1)
2073                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2074
2075         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2076                 int want_set = m->flags & MOPT_SET;
2077                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2078                     (m->flags & MOPT_CLEAR_ERR))
2079                         continue;
2080                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2081                         continue; /* skip if same as the default */
2082                 if ((want_set &&
2083                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2084                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2085                         continue; /* select Opt_noFoo vs Opt_Foo */
2086                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2087         }
2088
2089         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2090             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2091                 SEQ_OPTS_PRINT("resuid=%u",
2092                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2093         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2094             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2095                 SEQ_OPTS_PRINT("resgid=%u",
2096                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2097         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2098         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2099                 SEQ_OPTS_PUTS("errors=remount-ro");
2100         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2101                 SEQ_OPTS_PUTS("errors=continue");
2102         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2103                 SEQ_OPTS_PUTS("errors=panic");
2104         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2105                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2106         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2107                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2108         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2109                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2110         if (sb->s_flags & SB_I_VERSION)
2111                 SEQ_OPTS_PUTS("i_version");
2112         if (nodefs || sbi->s_stripe)
2113                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2114         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2115                         (sbi->s_mount_opt ^ def_mount_opt)) {
2116                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2117                         SEQ_OPTS_PUTS("data=journal");
2118                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2119                         SEQ_OPTS_PUTS("data=ordered");
2120                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2121                         SEQ_OPTS_PUTS("data=writeback");
2122         }
2123         if (nodefs ||
2124             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2125                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2126                                sbi->s_inode_readahead_blks);
2127
2128         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2129                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2130                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2131         if (nodefs || sbi->s_max_dir_size_kb)
2132                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2133         if (test_opt(sb, DATA_ERR_ABORT))
2134                 SEQ_OPTS_PUTS("data_err=abort");
2135
2136         ext4_show_quota_options(seq, sb);
2137         return 0;
2138 }
2139
2140 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2141 {
2142         return _ext4_show_options(seq, root->d_sb, 0);
2143 }
2144
2145 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2146 {
2147         struct super_block *sb = seq->private;
2148         int rc;
2149
2150         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2151         rc = _ext4_show_options(seq, sb, 1);
2152         seq_puts(seq, "\n");
2153         return rc;
2154 }
2155
2156 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2157                             int read_only)
2158 {
2159         struct ext4_sb_info *sbi = EXT4_SB(sb);
2160         int err = 0;
2161
2162         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2163                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2164                          "forcing read-only mode");
2165                 err = -EROFS;
2166         }
2167         if (read_only)
2168                 goto done;
2169         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2170                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2171                          "running e2fsck is recommended");
2172         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2173                 ext4_msg(sb, KERN_WARNING,
2174                          "warning: mounting fs with errors, "
2175                          "running e2fsck is recommended");
2176         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2177                  le16_to_cpu(es->s_mnt_count) >=
2178                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2179                 ext4_msg(sb, KERN_WARNING,
2180                          "warning: maximal mount count reached, "
2181                          "running e2fsck is recommended");
2182         else if (le32_to_cpu(es->s_checkinterval) &&
2183                 (le32_to_cpu(es->s_lastcheck) +
2184                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
2185                 ext4_msg(sb, KERN_WARNING,
2186                          "warning: checktime reached, "
2187                          "running e2fsck is recommended");
2188         if (!sbi->s_journal)
2189                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2190         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2191                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2192         le16_add_cpu(&es->s_mnt_count, 1);
2193         es->s_mtime = cpu_to_le32(get_seconds());
2194         ext4_update_dynamic_rev(sb);
2195         if (sbi->s_journal)
2196                 ext4_set_feature_journal_needs_recovery(sb);
2197
2198         err = ext4_commit_super(sb, 1);
2199 done:
2200         if (test_opt(sb, DEBUG))
2201                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2202                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2203                         sb->s_blocksize,
2204                         sbi->s_groups_count,
2205                         EXT4_BLOCKS_PER_GROUP(sb),
2206                         EXT4_INODES_PER_GROUP(sb),
2207                         sbi->s_mount_opt, sbi->s_mount_opt2);
2208
2209         cleancache_init_fs(sb);
2210         return err;
2211 }
2212
2213 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2214 {
2215         struct ext4_sb_info *sbi = EXT4_SB(sb);
2216         struct flex_groups *new_groups;
2217         int size;
2218
2219         if (!sbi->s_log_groups_per_flex)
2220                 return 0;
2221
2222         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2223         if (size <= sbi->s_flex_groups_allocated)
2224                 return 0;
2225
2226         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2227         new_groups = kvzalloc(size, GFP_KERNEL);
2228         if (!new_groups) {
2229                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2230                          size / (int) sizeof(struct flex_groups));
2231                 return -ENOMEM;
2232         }
2233
2234         if (sbi->s_flex_groups) {
2235                 memcpy(new_groups, sbi->s_flex_groups,
2236                        (sbi->s_flex_groups_allocated *
2237                         sizeof(struct flex_groups)));
2238                 kvfree(sbi->s_flex_groups);
2239         }
2240         sbi->s_flex_groups = new_groups;
2241         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2242         return 0;
2243 }
2244
2245 static int ext4_fill_flex_info(struct super_block *sb)
2246 {
2247         struct ext4_sb_info *sbi = EXT4_SB(sb);
2248         struct ext4_group_desc *gdp = NULL;
2249         ext4_group_t flex_group;
2250         int i, err;
2251
2252         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2253         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2254                 sbi->s_log_groups_per_flex = 0;
2255                 return 1;
2256         }
2257
2258         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2259         if (err)
2260                 goto failed;
2261
2262         for (i = 0; i < sbi->s_groups_count; i++) {
2263                 gdp = ext4_get_group_desc(sb, i, NULL);
2264
2265                 flex_group = ext4_flex_group(sbi, i);
2266                 atomic_add(ext4_free_inodes_count(sb, gdp),
2267                            &sbi->s_flex_groups[flex_group].free_inodes);
2268                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2269                              &sbi->s_flex_groups[flex_group].free_clusters);
2270                 atomic_add(ext4_used_dirs_count(sb, gdp),
2271                            &sbi->s_flex_groups[flex_group].used_dirs);
2272         }
2273
2274         return 1;
2275 failed:
2276         return 0;
2277 }
2278
2279 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2280                                    struct ext4_group_desc *gdp)
2281 {
2282         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2283         __u16 crc = 0;
2284         __le32 le_group = cpu_to_le32(block_group);
2285         struct ext4_sb_info *sbi = EXT4_SB(sb);
2286
2287         if (ext4_has_metadata_csum(sbi->s_sb)) {
2288                 /* Use new metadata_csum algorithm */
2289                 __u32 csum32;
2290                 __u16 dummy_csum = 0;
2291
2292                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2293                                      sizeof(le_group));
2294                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2295                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2296                                      sizeof(dummy_csum));
2297                 offset += sizeof(dummy_csum);
2298                 if (offset < sbi->s_desc_size)
2299                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2300                                              sbi->s_desc_size - offset);
2301
2302                 crc = csum32 & 0xFFFF;
2303                 goto out;
2304         }
2305
2306         /* old crc16 code */
2307         if (!ext4_has_feature_gdt_csum(sb))
2308                 return 0;
2309
2310         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2311         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2312         crc = crc16(crc, (__u8 *)gdp, offset);
2313         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2314         /* for checksum of struct ext4_group_desc do the rest...*/
2315         if (ext4_has_feature_64bit(sb) &&
2316             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2317                 crc = crc16(crc, (__u8 *)gdp + offset,
2318                             le16_to_cpu(sbi->s_es->s_desc_size) -
2319                                 offset);
2320
2321 out:
2322         return cpu_to_le16(crc);
2323 }
2324
2325 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2326                                 struct ext4_group_desc *gdp)
2327 {
2328         if (ext4_has_group_desc_csum(sb) &&
2329             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2330                 return 0;
2331
2332         return 1;
2333 }
2334
2335 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2336                               struct ext4_group_desc *gdp)
2337 {
2338         if (!ext4_has_group_desc_csum(sb))
2339                 return;
2340         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2341 }
2342
2343 /* Called at mount-time, super-block is locked */
2344 static int ext4_check_descriptors(struct super_block *sb,
2345                                   ext4_fsblk_t sb_block,
2346                                   ext4_group_t *first_not_zeroed)
2347 {
2348         struct ext4_sb_info *sbi = EXT4_SB(sb);
2349         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2350         ext4_fsblk_t last_block;
2351         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0) + 1;
2352         ext4_fsblk_t block_bitmap;
2353         ext4_fsblk_t inode_bitmap;
2354         ext4_fsblk_t inode_table;
2355         int flexbg_flag = 0;
2356         ext4_group_t i, grp = sbi->s_groups_count;
2357
2358         if (ext4_has_feature_flex_bg(sb))
2359                 flexbg_flag = 1;
2360
2361         ext4_debug("Checking group descriptors");
2362
2363         for (i = 0; i < sbi->s_groups_count; i++) {
2364                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2365
2366                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2367                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2368                 else
2369                         last_block = first_block +
2370                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2371
2372                 if ((grp == sbi->s_groups_count) &&
2373                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2374                         grp = i;
2375
2376                 block_bitmap = ext4_block_bitmap(sb, gdp);
2377                 if (block_bitmap == sb_block) {
2378                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2379                                  "Block bitmap for group %u overlaps "
2380                                  "superblock", i);
2381                         if (!sb_rdonly(sb))
2382                                 return 0;
2383                 }
2384                 if (block_bitmap >= sb_block + 1 &&
2385                     block_bitmap <= last_bg_block) {
2386                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2387                                  "Block bitmap for group %u overlaps "
2388                                  "block group descriptors", i);
2389                         if (!sb_rdonly(sb))
2390                                 return 0;
2391                 }
2392                 if (block_bitmap < first_block || block_bitmap > last_block) {
2393                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2394                                "Block bitmap for group %u not in group "
2395                                "(block %llu)!", i, block_bitmap);
2396                         return 0;
2397                 }
2398                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2399                 if (inode_bitmap == sb_block) {
2400                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2401                                  "Inode bitmap for group %u overlaps "
2402                                  "superblock", i);
2403                         if (!sb_rdonly(sb))
2404                                 return 0;
2405                 }
2406                 if (inode_bitmap >= sb_block + 1 &&
2407                     inode_bitmap <= last_bg_block) {
2408                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2409                                  "Inode bitmap for group %u overlaps "
2410                                  "block group descriptors", i);
2411                         if (!sb_rdonly(sb))
2412                                 return 0;
2413                 }
2414                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2415                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2416                                "Inode bitmap for group %u not in group "
2417                                "(block %llu)!", i, inode_bitmap);
2418                         return 0;
2419                 }
2420                 inode_table = ext4_inode_table(sb, gdp);
2421                 if (inode_table == sb_block) {
2422                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2423                                  "Inode table for group %u overlaps "
2424                                  "superblock", i);
2425                         if (!sb_rdonly(sb))
2426                                 return 0;
2427                 }
2428                 if (inode_table >= sb_block + 1 &&
2429                     inode_table <= last_bg_block) {
2430                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2431                                  "Inode table for group %u overlaps "
2432                                  "block group descriptors", i);
2433                         if (!sb_rdonly(sb))
2434                                 return 0;
2435                 }
2436                 if (inode_table < first_block ||
2437                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2438                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2439                                "Inode table for group %u not in group "
2440                                "(block %llu)!", i, inode_table);
2441                         return 0;
2442                 }
2443                 ext4_lock_group(sb, i);
2444                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2445                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2446                                  "Checksum for group %u failed (%u!=%u)",
2447                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2448                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2449                         if (!sb_rdonly(sb)) {
2450                                 ext4_unlock_group(sb, i);
2451                                 return 0;
2452                         }
2453                 }
2454                 ext4_unlock_group(sb, i);
2455                 if (!flexbg_flag)
2456                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2457         }
2458         if (NULL != first_not_zeroed)
2459                 *first_not_zeroed = grp;
2460         return 1;
2461 }
2462
2463 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2464  * the superblock) which were deleted from all directories, but held open by
2465  * a process at the time of a crash.  We walk the list and try to delete these
2466  * inodes at recovery time (only with a read-write filesystem).
2467  *
2468  * In order to keep the orphan inode chain consistent during traversal (in
2469  * case of crash during recovery), we link each inode into the superblock
2470  * orphan list_head and handle it the same way as an inode deletion during
2471  * normal operation (which journals the operations for us).
2472  *
2473  * We only do an iget() and an iput() on each inode, which is very safe if we
2474  * accidentally point at an in-use or already deleted inode.  The worst that
2475  * can happen in this case is that we get a "bit already cleared" message from
2476  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2477  * e2fsck was run on this filesystem, and it must have already done the orphan
2478  * inode cleanup for us, so we can safely abort without any further action.
2479  */
2480 static void ext4_orphan_cleanup(struct super_block *sb,
2481                                 struct ext4_super_block *es)
2482 {
2483         unsigned int s_flags = sb->s_flags;
2484         int ret, nr_orphans = 0, nr_truncates = 0;
2485 #ifdef CONFIG_QUOTA
2486         int quota_update = 0;
2487         int i;
2488 #endif
2489         if (!es->s_last_orphan) {
2490                 jbd_debug(4, "no orphan inodes to clean up\n");
2491                 return;
2492         }
2493
2494         if (bdev_read_only(sb->s_bdev)) {
2495                 ext4_msg(sb, KERN_ERR, "write access "
2496                         "unavailable, skipping orphan cleanup");
2497                 return;
2498         }
2499
2500         /* Check if feature set would not allow a r/w mount */
2501         if (!ext4_feature_set_ok(sb, 0)) {
2502                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2503                          "unknown ROCOMPAT features");
2504                 return;
2505         }
2506
2507         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2508                 /* don't clear list on RO mount w/ errors */
2509                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2510                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2511                                   "clearing orphan list.\n");
2512                         es->s_last_orphan = 0;
2513                 }
2514                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2515                 return;
2516         }
2517
2518         if (s_flags & SB_RDONLY) {
2519                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2520                 sb->s_flags &= ~SB_RDONLY;
2521         }
2522 #ifdef CONFIG_QUOTA
2523         /* Needed for iput() to work correctly and not trash data */
2524         sb->s_flags |= SB_ACTIVE;
2525
2526         /*
2527          * Turn on quotas which were not enabled for read-only mounts if
2528          * filesystem has quota feature, so that they are updated correctly.
2529          */
2530         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2531                 int ret = ext4_enable_quotas(sb);
2532
2533                 if (!ret)
2534                         quota_update = 1;
2535                 else
2536                         ext4_msg(sb, KERN_ERR,
2537                                 "Cannot turn on quotas: error %d", ret);
2538         }
2539
2540         /* Turn on journaled quotas used for old sytle */
2541         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2542                 if (EXT4_SB(sb)->s_qf_names[i]) {
2543                         int ret = ext4_quota_on_mount(sb, i);
2544
2545                         if (!ret)
2546                                 quota_update = 1;
2547                         else
2548                                 ext4_msg(sb, KERN_ERR,
2549                                         "Cannot turn on journaled "
2550                                         "quota: type %d: error %d", i, ret);
2551                 }
2552         }
2553 #endif
2554
2555         while (es->s_last_orphan) {
2556                 struct inode *inode;
2557
2558                 /*
2559                  * We may have encountered an error during cleanup; if
2560                  * so, skip the rest.
2561                  */
2562                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2563                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2564                         es->s_last_orphan = 0;
2565                         break;
2566                 }
2567
2568                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2569                 if (IS_ERR(inode)) {
2570                         es->s_last_orphan = 0;
2571                         break;
2572                 }
2573
2574                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2575                 dquot_initialize(inode);
2576                 if (inode->i_nlink) {
2577                         if (test_opt(sb, DEBUG))
2578                                 ext4_msg(sb, KERN_DEBUG,
2579                                         "%s: truncating inode %lu to %lld bytes",
2580                                         __func__, inode->i_ino, inode->i_size);
2581                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2582                                   inode->i_ino, inode->i_size);
2583                         inode_lock(inode);
2584                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2585                         ret = ext4_truncate(inode);
2586                         if (ret)
2587                                 ext4_std_error(inode->i_sb, ret);
2588                         inode_unlock(inode);
2589                         nr_truncates++;
2590                 } else {
2591                         if (test_opt(sb, DEBUG))
2592                                 ext4_msg(sb, KERN_DEBUG,
2593                                         "%s: deleting unreferenced inode %lu",
2594                                         __func__, inode->i_ino);
2595                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2596                                   inode->i_ino);
2597                         nr_orphans++;
2598                 }
2599                 iput(inode);  /* The delete magic happens here! */
2600         }
2601
2602 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2603
2604         if (nr_orphans)
2605                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2606                        PLURAL(nr_orphans));
2607         if (nr_truncates)
2608                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2609                        PLURAL(nr_truncates));
2610 #ifdef CONFIG_QUOTA
2611         /* Turn off quotas if they were enabled for orphan cleanup */
2612         if (quota_update) {
2613                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2614                         if (sb_dqopt(sb)->files[i])
2615                                 dquot_quota_off(sb, i);
2616                 }
2617         }
2618 #endif
2619         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2620 }
2621
2622 /*
2623  * Maximal extent format file size.
2624  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2625  * extent format containers, within a sector_t, and within i_blocks
2626  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2627  * so that won't be a limiting factor.
2628  *
2629  * However there is other limiting factor. We do store extents in the form
2630  * of starting block and length, hence the resulting length of the extent
2631  * covering maximum file size must fit into on-disk format containers as
2632  * well. Given that length is always by 1 unit bigger than max unit (because
2633  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2634  *
2635  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2636  */
2637 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2638 {
2639         loff_t res;
2640         loff_t upper_limit = MAX_LFS_FILESIZE;
2641
2642         /* small i_blocks in vfs inode? */
2643         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2644                 /*
2645                  * CONFIG_LBDAF is not enabled implies the inode
2646                  * i_block represent total blocks in 512 bytes
2647                  * 32 == size of vfs inode i_blocks * 8
2648                  */
2649                 upper_limit = (1LL << 32) - 1;
2650
2651                 /* total blocks in file system block size */
2652                 upper_limit >>= (blkbits - 9);
2653                 upper_limit <<= blkbits;
2654         }
2655
2656         /*
2657          * 32-bit extent-start container, ee_block. We lower the maxbytes
2658          * by one fs block, so ee_len can cover the extent of maximum file
2659          * size
2660          */
2661         res = (1LL << 32) - 1;
2662         res <<= blkbits;
2663
2664         /* Sanity check against vm- & vfs- imposed limits */
2665         if (res > upper_limit)
2666                 res = upper_limit;
2667
2668         return res;
2669 }
2670
2671 /*
2672  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2673  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2674  * We need to be 1 filesystem block less than the 2^48 sector limit.
2675  */
2676 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2677 {
2678         loff_t res = EXT4_NDIR_BLOCKS;
2679         int meta_blocks;
2680         loff_t upper_limit;
2681         /* This is calculated to be the largest file size for a dense, block
2682          * mapped file such that the file's total number of 512-byte sectors,
2683          * including data and all indirect blocks, does not exceed (2^48 - 1).
2684          *
2685          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2686          * number of 512-byte sectors of the file.
2687          */
2688
2689         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2690                 /*
2691                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2692                  * the inode i_block field represents total file blocks in
2693                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2694                  */
2695                 upper_limit = (1LL << 32) - 1;
2696
2697                 /* total blocks in file system block size */
2698                 upper_limit >>= (bits - 9);
2699
2700         } else {
2701                 /*
2702                  * We use 48 bit ext4_inode i_blocks
2703                  * With EXT4_HUGE_FILE_FL set the i_blocks
2704                  * represent total number of blocks in
2705                  * file system block size
2706                  */
2707                 upper_limit = (1LL << 48) - 1;
2708
2709         }
2710
2711         /* indirect blocks */
2712         meta_blocks = 1;
2713         /* double indirect blocks */
2714         meta_blocks += 1 + (1LL << (bits-2));
2715         /* tripple indirect blocks */
2716         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2717
2718         upper_limit -= meta_blocks;
2719         upper_limit <<= bits;
2720
2721         res += 1LL << (bits-2);
2722         res += 1LL << (2*(bits-2));
2723         res += 1LL << (3*(bits-2));
2724         res <<= bits;
2725         if (res > upper_limit)
2726                 res = upper_limit;
2727
2728         if (res > MAX_LFS_FILESIZE)
2729                 res = MAX_LFS_FILESIZE;
2730
2731         return res;
2732 }
2733
2734 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2735                                    ext4_fsblk_t logical_sb_block, int nr)
2736 {
2737         struct ext4_sb_info *sbi = EXT4_SB(sb);
2738         ext4_group_t bg, first_meta_bg;
2739         int has_super = 0;
2740
2741         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2742
2743         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2744                 return logical_sb_block + nr + 1;
2745         bg = sbi->s_desc_per_block * nr;
2746         if (ext4_bg_has_super(sb, bg))
2747                 has_super = 1;
2748
2749         /*
2750          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2751          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2752          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2753          * compensate.
2754          */
2755         if (sb->s_blocksize == 1024 && nr == 0 &&
2756             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2757                 has_super++;
2758
2759         return (has_super + ext4_group_first_block_no(sb, bg));
2760 }
2761
2762 /**
2763  * ext4_get_stripe_size: Get the stripe size.
2764  * @sbi: In memory super block info
2765  *
2766  * If we have specified it via mount option, then
2767  * use the mount option value. If the value specified at mount time is
2768  * greater than the blocks per group use the super block value.
2769  * If the super block value is greater than blocks per group return 0.
2770  * Allocator needs it be less than blocks per group.
2771  *
2772  */
2773 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2774 {
2775         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2776         unsigned long stripe_width =
2777                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2778         int ret;
2779
2780         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2781                 ret = sbi->s_stripe;
2782         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2783                 ret = stripe_width;
2784         else if (stride && stride <= sbi->s_blocks_per_group)
2785                 ret = stride;
2786         else
2787                 ret = 0;
2788
2789         /*
2790          * If the stripe width is 1, this makes no sense and
2791          * we set it to 0 to turn off stripe handling code.
2792          */
2793         if (ret <= 1)
2794                 ret = 0;
2795
2796         return ret;
2797 }
2798
2799 /*
2800  * Check whether this filesystem can be mounted based on
2801  * the features present and the RDONLY/RDWR mount requested.
2802  * Returns 1 if this filesystem can be mounted as requested,
2803  * 0 if it cannot be.
2804  */
2805 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2806 {
2807         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2808                 ext4_msg(sb, KERN_ERR,
2809                         "Couldn't mount because of "
2810                         "unsupported optional features (%x)",
2811                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2812                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2813                 return 0;
2814         }
2815
2816         if (readonly)
2817                 return 1;
2818
2819         if (ext4_has_feature_readonly(sb)) {
2820                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2821                 sb->s_flags |= SB_RDONLY;
2822                 return 1;
2823         }
2824
2825         /* Check that feature set is OK for a read-write mount */
2826         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2827                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2828                          "unsupported optional features (%x)",
2829                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2830                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2831                 return 0;
2832         }
2833         /*
2834          * Large file size enabled file system can only be mounted
2835          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2836          */
2837         if (ext4_has_feature_huge_file(sb)) {
2838                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2839                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2840                                  "cannot be mounted RDWR without "
2841                                  "CONFIG_LBDAF");
2842                         return 0;
2843                 }
2844         }
2845         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2846                 ext4_msg(sb, KERN_ERR,
2847                          "Can't support bigalloc feature without "
2848                          "extents feature\n");
2849                 return 0;
2850         }
2851
2852 #ifndef CONFIG_QUOTA
2853         if (ext4_has_feature_quota(sb) && !readonly) {
2854                 ext4_msg(sb, KERN_ERR,
2855                          "Filesystem with quota feature cannot be mounted RDWR "
2856                          "without CONFIG_QUOTA");
2857                 return 0;
2858         }
2859         if (ext4_has_feature_project(sb) && !readonly) {
2860                 ext4_msg(sb, KERN_ERR,
2861                          "Filesystem with project quota feature cannot be mounted RDWR "
2862                          "without CONFIG_QUOTA");
2863                 return 0;
2864         }
2865 #endif  /* CONFIG_QUOTA */
2866         return 1;
2867 }
2868
2869 /*
2870  * This function is called once a day if we have errors logged
2871  * on the file system
2872  */
2873 static void print_daily_error_info(struct timer_list *t)
2874 {
2875         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2876         struct super_block *sb = sbi->s_sb;
2877         struct ext4_super_block *es = sbi->s_es;
2878
2879         if (es->s_error_count)
2880                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2881                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2882                          le32_to_cpu(es->s_error_count));
2883         if (es->s_first_error_time) {
2884                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2885                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2886                        (int) sizeof(es->s_first_error_func),
2887                        es->s_first_error_func,
2888                        le32_to_cpu(es->s_first_error_line));
2889                 if (es->s_first_error_ino)
2890                         printk(KERN_CONT ": inode %u",
2891                                le32_to_cpu(es->s_first_error_ino));
2892                 if (es->s_first_error_block)
2893                         printk(KERN_CONT ": block %llu", (unsigned long long)
2894                                le64_to_cpu(es->s_first_error_block));
2895                 printk(KERN_CONT "\n");
2896         }
2897         if (es->s_last_error_time) {
2898                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2899                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2900                        (int) sizeof(es->s_last_error_func),
2901                        es->s_last_error_func,
2902                        le32_to_cpu(es->s_last_error_line));
2903                 if (es->s_last_error_ino)
2904                         printk(KERN_CONT ": inode %u",
2905                                le32_to_cpu(es->s_last_error_ino));
2906                 if (es->s_last_error_block)
2907                         printk(KERN_CONT ": block %llu", (unsigned long long)
2908                                le64_to_cpu(es->s_last_error_block));
2909                 printk(KERN_CONT "\n");
2910         }
2911         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2912 }
2913
2914 /* Find next suitable group and run ext4_init_inode_table */
2915 static int ext4_run_li_request(struct ext4_li_request *elr)
2916 {
2917         struct ext4_group_desc *gdp = NULL;
2918         ext4_group_t group, ngroups;
2919         struct super_block *sb;
2920         unsigned long timeout = 0;
2921         int ret = 0;
2922
2923         sb = elr->lr_super;
2924         ngroups = EXT4_SB(sb)->s_groups_count;
2925
2926         for (group = elr->lr_next_group; group < ngroups; group++) {
2927                 gdp = ext4_get_group_desc(sb, group, NULL);
2928                 if (!gdp) {
2929                         ret = 1;
2930                         break;
2931                 }
2932
2933                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2934                         break;
2935         }
2936
2937         if (group >= ngroups)
2938                 ret = 1;
2939
2940         if (!ret) {
2941                 timeout = jiffies;
2942                 ret = ext4_init_inode_table(sb, group,
2943                                             elr->lr_timeout ? 0 : 1);
2944                 if (elr->lr_timeout == 0) {
2945                         timeout = (jiffies - timeout) *
2946                                   elr->lr_sbi->s_li_wait_mult;
2947                         elr->lr_timeout = timeout;
2948                 }
2949                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2950                 elr->lr_next_group = group + 1;
2951         }
2952         return ret;
2953 }
2954
2955 /*
2956  * Remove lr_request from the list_request and free the
2957  * request structure. Should be called with li_list_mtx held
2958  */
2959 static void ext4_remove_li_request(struct ext4_li_request *elr)
2960 {
2961         struct ext4_sb_info *sbi;
2962
2963         if (!elr)
2964                 return;
2965
2966         sbi = elr->lr_sbi;
2967
2968         list_del(&elr->lr_request);
2969         sbi->s_li_request = NULL;
2970         kfree(elr);
2971 }
2972
2973 static void ext4_unregister_li_request(struct super_block *sb)
2974 {
2975         mutex_lock(&ext4_li_mtx);
2976         if (!ext4_li_info) {
2977                 mutex_unlock(&ext4_li_mtx);
2978                 return;
2979         }
2980
2981         mutex_lock(&ext4_li_info->li_list_mtx);
2982         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2983         mutex_unlock(&ext4_li_info->li_list_mtx);
2984         mutex_unlock(&ext4_li_mtx);
2985 }
2986
2987 static struct task_struct *ext4_lazyinit_task;
2988
2989 /*
2990  * This is the function where ext4lazyinit thread lives. It walks
2991  * through the request list searching for next scheduled filesystem.
2992  * When such a fs is found, run the lazy initialization request
2993  * (ext4_rn_li_request) and keep track of the time spend in this
2994  * function. Based on that time we compute next schedule time of
2995  * the request. When walking through the list is complete, compute
2996  * next waking time and put itself into sleep.
2997  */
2998 static int ext4_lazyinit_thread(void *arg)
2999 {
3000         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3001         struct list_head *pos, *n;
3002         struct ext4_li_request *elr;
3003         unsigned long next_wakeup, cur;
3004
3005         BUG_ON(NULL == eli);
3006
3007 cont_thread:
3008         while (true) {
3009                 next_wakeup = MAX_JIFFY_OFFSET;
3010
3011                 mutex_lock(&eli->li_list_mtx);
3012                 if (list_empty(&eli->li_request_list)) {
3013                         mutex_unlock(&eli->li_list_mtx);
3014                         goto exit_thread;
3015                 }
3016                 list_for_each_safe(pos, n, &eli->li_request_list) {
3017                         int err = 0;
3018                         int progress = 0;
3019                         elr = list_entry(pos, struct ext4_li_request,
3020                                          lr_request);
3021
3022                         if (time_before(jiffies, elr->lr_next_sched)) {
3023                                 if (time_before(elr->lr_next_sched, next_wakeup))
3024                                         next_wakeup = elr->lr_next_sched;
3025                                 continue;
3026                         }
3027                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3028                                 if (sb_start_write_trylock(elr->lr_super)) {
3029                                         progress = 1;
3030                                         /*
3031                                          * We hold sb->s_umount, sb can not
3032                                          * be removed from the list, it is
3033                                          * now safe to drop li_list_mtx
3034                                          */
3035                                         mutex_unlock(&eli->li_list_mtx);
3036                                         err = ext4_run_li_request(elr);
3037                                         sb_end_write(elr->lr_super);
3038                                         mutex_lock(&eli->li_list_mtx);
3039                                         n = pos->next;
3040                                 }
3041                                 up_read((&elr->lr_super->s_umount));
3042                         }
3043                         /* error, remove the lazy_init job */
3044                         if (err) {
3045                                 ext4_remove_li_request(elr);
3046                                 continue;
3047                         }
3048                         if (!progress) {
3049                                 elr->lr_next_sched = jiffies +
3050                                         (prandom_u32()
3051                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3052                         }
3053                         if (time_before(elr->lr_next_sched, next_wakeup))
3054                                 next_wakeup = elr->lr_next_sched;
3055                 }
3056                 mutex_unlock(&eli->li_list_mtx);
3057
3058                 try_to_freeze();
3059
3060                 cur = jiffies;
3061                 if ((time_after_eq(cur, next_wakeup)) ||
3062                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3063                         cond_resched();
3064                         continue;
3065                 }
3066
3067                 schedule_timeout_interruptible(next_wakeup - cur);
3068
3069                 if (kthread_should_stop()) {
3070                         ext4_clear_request_list();
3071                         goto exit_thread;
3072                 }
3073         }
3074
3075 exit_thread:
3076         /*
3077          * It looks like the request list is empty, but we need
3078          * to check it under the li_list_mtx lock, to prevent any
3079          * additions into it, and of course we should lock ext4_li_mtx
3080          * to atomically free the list and ext4_li_info, because at
3081          * this point another ext4 filesystem could be registering
3082          * new one.
3083          */
3084         mutex_lock(&ext4_li_mtx);
3085         mutex_lock(&eli->li_list_mtx);
3086         if (!list_empty(&eli->li_request_list)) {
3087                 mutex_unlock(&eli->li_list_mtx);
3088                 mutex_unlock(&ext4_li_mtx);
3089                 goto cont_thread;
3090         }
3091         mutex_unlock(&eli->li_list_mtx);
3092         kfree(ext4_li_info);
3093         ext4_li_info = NULL;
3094         mutex_unlock(&ext4_li_mtx);
3095
3096         return 0;
3097 }
3098
3099 static void ext4_clear_request_list(void)
3100 {
3101         struct list_head *pos, *n;
3102         struct ext4_li_request *elr;
3103
3104         mutex_lock(&ext4_li_info->li_list_mtx);
3105         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3106                 elr = list_entry(pos, struct ext4_li_request,
3107                                  lr_request);
3108                 ext4_remove_li_request(elr);
3109         }
3110         mutex_unlock(&ext4_li_info->li_list_mtx);
3111 }
3112
3113 static int ext4_run_lazyinit_thread(void)
3114 {
3115         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3116                                          ext4_li_info, "ext4lazyinit");
3117         if (IS_ERR(ext4_lazyinit_task)) {
3118                 int err = PTR_ERR(ext4_lazyinit_task);
3119                 ext4_clear_request_list();
3120                 kfree(ext4_li_info);
3121                 ext4_li_info = NULL;
3122                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3123                                  "initialization thread\n",
3124                                  err);
3125                 return err;
3126         }
3127         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3128         return 0;
3129 }
3130
3131 /*
3132  * Check whether it make sense to run itable init. thread or not.
3133  * If there is at least one uninitialized inode table, return
3134  * corresponding group number, else the loop goes through all
3135  * groups and return total number of groups.
3136  */
3137 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3138 {
3139         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3140         struct ext4_group_desc *gdp = NULL;
3141
3142         for (group = 0; group < ngroups; group++) {
3143                 gdp = ext4_get_group_desc(sb, group, NULL);
3144                 if (!gdp)
3145                         continue;
3146
3147                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3148                         break;
3149         }
3150
3151         return group;
3152 }
3153
3154 static int ext4_li_info_new(void)
3155 {
3156         struct ext4_lazy_init *eli = NULL;
3157
3158         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3159         if (!eli)
3160                 return -ENOMEM;
3161
3162         INIT_LIST_HEAD(&eli->li_request_list);
3163         mutex_init(&eli->li_list_mtx);
3164
3165         eli->li_state |= EXT4_LAZYINIT_QUIT;
3166
3167         ext4_li_info = eli;
3168
3169         return 0;
3170 }
3171
3172 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3173                                             ext4_group_t start)
3174 {
3175         struct ext4_sb_info *sbi = EXT4_SB(sb);
3176         struct ext4_li_request *elr;
3177
3178         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3179         if (!elr)
3180                 return NULL;
3181
3182         elr->lr_super = sb;
3183         elr->lr_sbi = sbi;
3184         elr->lr_next_group = start;
3185
3186         /*
3187          * Randomize first schedule time of the request to
3188          * spread the inode table initialization requests
3189          * better.
3190          */
3191         elr->lr_next_sched = jiffies + (prandom_u32() %
3192                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3193         return elr;
3194 }
3195
3196 int ext4_register_li_request(struct super_block *sb,
3197                              ext4_group_t first_not_zeroed)
3198 {
3199         struct ext4_sb_info *sbi = EXT4_SB(sb);
3200         struct ext4_li_request *elr = NULL;
3201         ext4_group_t ngroups = sbi->s_groups_count;
3202         int ret = 0;
3203
3204         mutex_lock(&ext4_li_mtx);
3205         if (sbi->s_li_request != NULL) {
3206                 /*
3207                  * Reset timeout so it can be computed again, because
3208                  * s_li_wait_mult might have changed.
3209                  */
3210                 sbi->s_li_request->lr_timeout = 0;
3211                 goto out;
3212         }
3213
3214         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3215             !test_opt(sb, INIT_INODE_TABLE))
3216                 goto out;
3217
3218         elr = ext4_li_request_new(sb, first_not_zeroed);
3219         if (!elr) {
3220                 ret = -ENOMEM;
3221                 goto out;
3222         }
3223
3224         if (NULL == ext4_li_info) {
3225                 ret = ext4_li_info_new();
3226                 if (ret)
3227                         goto out;
3228         }
3229
3230         mutex_lock(&ext4_li_info->li_list_mtx);
3231         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3232         mutex_unlock(&ext4_li_info->li_list_mtx);
3233
3234         sbi->s_li_request = elr;
3235         /*
3236          * set elr to NULL here since it has been inserted to
3237          * the request_list and the removal and free of it is
3238          * handled by ext4_clear_request_list from now on.
3239          */
3240         elr = NULL;
3241
3242         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3243                 ret = ext4_run_lazyinit_thread();
3244                 if (ret)
3245                         goto out;
3246         }
3247 out:
3248         mutex_unlock(&ext4_li_mtx);
3249         if (ret)
3250                 kfree(elr);
3251         return ret;
3252 }
3253
3254 /*
3255  * We do not need to lock anything since this is called on
3256  * module unload.
3257  */
3258 static void ext4_destroy_lazyinit_thread(void)
3259 {
3260         /*
3261          * If thread exited earlier
3262          * there's nothing to be done.
3263          */
3264         if (!ext4_li_info || !ext4_lazyinit_task)
3265                 return;
3266
3267         kthread_stop(ext4_lazyinit_task);
3268 }
3269
3270 static int set_journal_csum_feature_set(struct super_block *sb)
3271 {
3272         int ret = 1;
3273         int compat, incompat;
3274         struct ext4_sb_info *sbi = EXT4_SB(sb);
3275
3276         if (ext4_has_metadata_csum(sb)) {
3277                 /* journal checksum v3 */
3278                 compat = 0;
3279                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3280         } else {
3281                 /* journal checksum v1 */
3282                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3283                 incompat = 0;
3284         }
3285
3286         jbd2_journal_clear_features(sbi->s_journal,
3287                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3288                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3289                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3290         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3291                 ret = jbd2_journal_set_features(sbi->s_journal,
3292                                 compat, 0,
3293                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3294                                 incompat);
3295         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3296                 ret = jbd2_journal_set_features(sbi->s_journal,
3297                                 compat, 0,
3298                                 incompat);
3299                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3300                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3301         } else {
3302                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3303                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3304         }
3305
3306         return ret;
3307 }
3308
3309 /*
3310  * Note: calculating the overhead so we can be compatible with
3311  * historical BSD practice is quite difficult in the face of
3312  * clusters/bigalloc.  This is because multiple metadata blocks from
3313  * different block group can end up in the same allocation cluster.
3314  * Calculating the exact overhead in the face of clustered allocation
3315  * requires either O(all block bitmaps) in memory or O(number of block
3316  * groups**2) in time.  We will still calculate the superblock for
3317  * older file systems --- and if we come across with a bigalloc file
3318  * system with zero in s_overhead_clusters the estimate will be close to
3319  * correct especially for very large cluster sizes --- but for newer
3320  * file systems, it's better to calculate this figure once at mkfs
3321  * time, and store it in the superblock.  If the superblock value is
3322  * present (even for non-bigalloc file systems), we will use it.
3323  */
3324 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3325                           char *buf)
3326 {
3327         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3328         struct ext4_group_desc  *gdp;
3329         ext4_fsblk_t            first_block, last_block, b;
3330         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3331         int                     s, j, count = 0;
3332
3333         if (!ext4_has_feature_bigalloc(sb))
3334                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3335                         sbi->s_itb_per_group + 2);
3336
3337         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3338                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3339         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3340         for (i = 0; i < ngroups; i++) {
3341                 gdp = ext4_get_group_desc(sb, i, NULL);
3342                 b = ext4_block_bitmap(sb, gdp);
3343                 if (b >= first_block && b <= last_block) {
3344                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3345                         count++;
3346                 }
3347                 b = ext4_inode_bitmap(sb, gdp);
3348                 if (b >= first_block && b <= last_block) {
3349                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3350                         count++;
3351                 }
3352                 b = ext4_inode_table(sb, gdp);
3353                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3354                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3355                                 int c = EXT4_B2C(sbi, b - first_block);
3356                                 ext4_set_bit(c, buf);
3357                                 count++;
3358                         }
3359                 if (i != grp)
3360                         continue;
3361                 s = 0;
3362                 if (ext4_bg_has_super(sb, grp)) {
3363                         ext4_set_bit(s++, buf);
3364                         count++;
3365                 }
3366                 j = ext4_bg_num_gdb(sb, grp);
3367                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3368                         ext4_error(sb, "Invalid number of block group "
3369                                    "descriptor blocks: %d", j);
3370                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3371                 }
3372                 count += j;
3373                 for (; j > 0; j--)
3374                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3375         }
3376         if (!count)
3377                 return 0;
3378         return EXT4_CLUSTERS_PER_GROUP(sb) -
3379                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3380 }
3381
3382 /*
3383  * Compute the overhead and stash it in sbi->s_overhead
3384  */
3385 int ext4_calculate_overhead(struct super_block *sb)
3386 {
3387         struct ext4_sb_info *sbi = EXT4_SB(sb);
3388         struct ext4_super_block *es = sbi->s_es;
3389         struct inode *j_inode;
3390         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3391         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3392         ext4_fsblk_t overhead = 0;
3393         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3394
3395         if (!buf)
3396                 return -ENOMEM;
3397
3398         /*
3399          * Compute the overhead (FS structures).  This is constant
3400          * for a given filesystem unless the number of block groups
3401          * changes so we cache the previous value until it does.
3402          */
3403
3404         /*
3405          * All of the blocks before first_data_block are overhead
3406          */
3407         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3408
3409         /*
3410          * Add the overhead found in each block group
3411          */
3412         for (i = 0; i < ngroups; i++) {
3413                 int blks;
3414
3415                 blks = count_overhead(sb, i, buf);
3416                 overhead += blks;
3417                 if (blks)
3418                         memset(buf, 0, PAGE_SIZE);
3419                 cond_resched();
3420         }
3421
3422         /*
3423          * Add the internal journal blocks whether the journal has been
3424          * loaded or not
3425          */
3426         if (sbi->s_journal && !sbi->journal_bdev)
3427                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3428         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3429                 j_inode = ext4_get_journal_inode(sb, j_inum);
3430                 if (j_inode) {
3431                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3432                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3433                         iput(j_inode);
3434                 } else {
3435                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3436                 }
3437         }
3438         sbi->s_overhead = overhead;
3439         smp_wmb();
3440         free_page((unsigned long) buf);
3441         return 0;
3442 }
3443
3444 static void ext4_set_resv_clusters(struct super_block *sb)
3445 {
3446         ext4_fsblk_t resv_clusters;
3447         struct ext4_sb_info *sbi = EXT4_SB(sb);
3448
3449         /*
3450          * There's no need to reserve anything when we aren't using extents.
3451          * The space estimates are exact, there are no unwritten extents,
3452          * hole punching doesn't need new metadata... This is needed especially
3453          * to keep ext2/3 backward compatibility.
3454          */
3455         if (!ext4_has_feature_extents(sb))
3456                 return;
3457         /*
3458          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3459          * This should cover the situations where we can not afford to run
3460          * out of space like for example punch hole, or converting
3461          * unwritten extents in delalloc path. In most cases such
3462          * allocation would require 1, or 2 blocks, higher numbers are
3463          * very rare.
3464          */
3465         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3466                          sbi->s_cluster_bits);
3467
3468         do_div(resv_clusters, 50);
3469         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3470
3471         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3472 }
3473
3474 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3475 {
3476         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3477         char *orig_data = kstrdup(data, GFP_KERNEL);
3478         struct buffer_head *bh;
3479         struct ext4_super_block *es = NULL;
3480         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3481         ext4_fsblk_t block;
3482         ext4_fsblk_t sb_block = get_sb_block(&data);
3483         ext4_fsblk_t logical_sb_block;
3484         unsigned long offset = 0;
3485         unsigned long journal_devnum = 0;
3486         unsigned long def_mount_opts;
3487         struct inode *root;
3488         const char *descr;
3489         int ret = -ENOMEM;
3490         int blocksize, clustersize;
3491         unsigned int db_count;
3492         unsigned int i;
3493         int needs_recovery, has_huge_files, has_bigalloc;
3494         __u64 blocks_count;
3495         int err = 0;
3496         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3497         ext4_group_t first_not_zeroed;
3498
3499         if ((data && !orig_data) || !sbi)
3500                 goto out_free_base;
3501
3502         sbi->s_daxdev = dax_dev;
3503         sbi->s_blockgroup_lock =
3504                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3505         if (!sbi->s_blockgroup_lock)
3506                 goto out_free_base;
3507
3508         sb->s_fs_info = sbi;
3509         sbi->s_sb = sb;
3510         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3511         sbi->s_sb_block = sb_block;
3512         if (sb->s_bdev->bd_part)
3513                 sbi->s_sectors_written_start =
3514                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3515
3516         /* Cleanup superblock name */
3517         strreplace(sb->s_id, '/', '!');
3518
3519         /* -EINVAL is default */
3520         ret = -EINVAL;
3521         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3522         if (!blocksize) {
3523                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3524                 goto out_fail;
3525         }
3526
3527         /*
3528          * The ext4 superblock will not be buffer aligned for other than 1kB
3529          * block sizes.  We need to calculate the offset from buffer start.
3530          */
3531         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3532                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3533                 offset = do_div(logical_sb_block, blocksize);
3534         } else {
3535                 logical_sb_block = sb_block;
3536         }
3537
3538         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3539                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3540                 goto out_fail;
3541         }
3542         /*
3543          * Note: s_es must be initialized as soon as possible because
3544          *       some ext4 macro-instructions depend on its value
3545          */
3546         es = (struct ext4_super_block *) (bh->b_data + offset);
3547         sbi->s_es = es;
3548         sb->s_magic = le16_to_cpu(es->s_magic);
3549         if (sb->s_magic != EXT4_SUPER_MAGIC)
3550                 goto cantfind_ext4;
3551         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3552
3553         /* Warn if metadata_csum and gdt_csum are both set. */
3554         if (ext4_has_feature_metadata_csum(sb) &&
3555             ext4_has_feature_gdt_csum(sb))
3556                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3557                              "redundant flags; please run fsck.");
3558
3559         /* Check for a known checksum algorithm */
3560         if (!ext4_verify_csum_type(sb, es)) {
3561                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3562                          "unknown checksum algorithm.");
3563                 silent = 1;
3564                 goto cantfind_ext4;
3565         }
3566
3567         /* Load the checksum driver */
3568         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3569         if (IS_ERR(sbi->s_chksum_driver)) {
3570                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3571                 ret = PTR_ERR(sbi->s_chksum_driver);
3572                 sbi->s_chksum_driver = NULL;
3573                 goto failed_mount;
3574         }
3575
3576         /* Check superblock checksum */
3577         if (!ext4_superblock_csum_verify(sb, es)) {
3578                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3579                          "invalid superblock checksum.  Run e2fsck?");
3580                 silent = 1;
3581                 ret = -EFSBADCRC;
3582                 goto cantfind_ext4;
3583         }
3584
3585         /* Precompute checksum seed for all metadata */
3586         if (ext4_has_feature_csum_seed(sb))
3587                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3588         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3589                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3590                                                sizeof(es->s_uuid));
3591
3592         /* Set defaults before we parse the mount options */
3593         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3594         set_opt(sb, INIT_INODE_TABLE);
3595         if (def_mount_opts & EXT4_DEFM_DEBUG)
3596                 set_opt(sb, DEBUG);
3597         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3598                 set_opt(sb, GRPID);
3599         if (def_mount_opts & EXT4_DEFM_UID16)
3600                 set_opt(sb, NO_UID32);
3601         /* xattr user namespace & acls are now defaulted on */
3602         set_opt(sb, XATTR_USER);
3603 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3604         set_opt(sb, POSIX_ACL);
3605 #endif
3606         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3607         if (ext4_has_metadata_csum(sb))
3608                 set_opt(sb, JOURNAL_CHECKSUM);
3609
3610         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3611                 set_opt(sb, JOURNAL_DATA);
3612         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3613                 set_opt(sb, ORDERED_DATA);
3614         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3615                 set_opt(sb, WRITEBACK_DATA);
3616
3617         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3618                 set_opt(sb, ERRORS_PANIC);
3619         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3620                 set_opt(sb, ERRORS_CONT);
3621         else
3622                 set_opt(sb, ERRORS_RO);
3623         /* block_validity enabled by default; disable with noblock_validity */
3624         set_opt(sb, BLOCK_VALIDITY);
3625         if (def_mount_opts & EXT4_DEFM_DISCARD)
3626                 set_opt(sb, DISCARD);
3627
3628         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3629         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3630         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3631         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3632         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3633
3634         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3635                 set_opt(sb, BARRIER);
3636
3637         /*
3638          * enable delayed allocation by default
3639          * Use -o nodelalloc to turn it off
3640          */
3641         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3642             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3643                 set_opt(sb, DELALLOC);
3644
3645         /*
3646          * set default s_li_wait_mult for lazyinit, for the case there is
3647          * no mount option specified.
3648          */
3649         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3650
3651         if (sbi->s_es->s_mount_opts[0]) {
3652                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3653                                               sizeof(sbi->s_es->s_mount_opts),
3654                                               GFP_KERNEL);
3655                 if (!s_mount_opts)
3656                         goto failed_mount;
3657                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3658                                    &journal_ioprio, 0)) {
3659                         ext4_msg(sb, KERN_WARNING,
3660                                  "failed to parse options in superblock: %s",
3661                                  s_mount_opts);
3662                 }
3663                 kfree(s_mount_opts);
3664         }
3665         sbi->s_def_mount_opt = sbi->s_mount_opt;
3666         if (!parse_options((char *) data, sb, &journal_devnum,
3667                            &journal_ioprio, 0))
3668                 goto failed_mount;
3669
3670         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3671                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3672                             "with data=journal disables delayed "
3673                             "allocation and O_DIRECT support!\n");
3674                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3675                         ext4_msg(sb, KERN_ERR, "can't mount with "
3676                                  "both data=journal and delalloc");
3677                         goto failed_mount;
3678                 }
3679                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3680                         ext4_msg(sb, KERN_ERR, "can't mount with "
3681                                  "both data=journal and dioread_nolock");
3682                         goto failed_mount;
3683                 }
3684                 if (test_opt(sb, DAX)) {
3685                         ext4_msg(sb, KERN_ERR, "can't mount with "
3686                                  "both data=journal and dax");
3687                         goto failed_mount;
3688                 }
3689                 if (ext4_has_feature_encrypt(sb)) {
3690                         ext4_msg(sb, KERN_WARNING,
3691                                  "encrypted files will use data=ordered "
3692                                  "instead of data journaling mode");
3693                 }
3694                 if (test_opt(sb, DELALLOC))
3695                         clear_opt(sb, DELALLOC);
3696         } else {
3697                 sb->s_iflags |= SB_I_CGROUPWB;
3698         }
3699
3700         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3701                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3702
3703         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3704             (ext4_has_compat_features(sb) ||
3705              ext4_has_ro_compat_features(sb) ||
3706              ext4_has_incompat_features(sb)))
3707                 ext4_msg(sb, KERN_WARNING,
3708                        "feature flags set on rev 0 fs, "
3709                        "running e2fsck is recommended");
3710
3711         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3712                 set_opt2(sb, HURD_COMPAT);
3713                 if (ext4_has_feature_64bit(sb)) {
3714                         ext4_msg(sb, KERN_ERR,
3715                                  "The Hurd can't support 64-bit file systems");
3716                         goto failed_mount;
3717                 }
3718
3719                 /*
3720                  * ea_inode feature uses l_i_version field which is not
3721                  * available in HURD_COMPAT mode.
3722                  */
3723                 if (ext4_has_feature_ea_inode(sb)) {
3724                         ext4_msg(sb, KERN_ERR,
3725                                  "ea_inode feature is not supported for Hurd");
3726                         goto failed_mount;
3727                 }
3728         }
3729
3730         if (IS_EXT2_SB(sb)) {
3731                 if (ext2_feature_set_ok(sb))
3732                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3733                                  "using the ext4 subsystem");
3734                 else {
3735                         /*
3736                          * If we're probing be silent, if this looks like
3737                          * it's actually an ext[34] filesystem.
3738                          */
3739                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3740                                 goto failed_mount;
3741                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3742                                  "to feature incompatibilities");
3743                         goto failed_mount;
3744                 }
3745         }
3746
3747         if (IS_EXT3_SB(sb)) {
3748                 if (ext3_feature_set_ok(sb))
3749                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3750                                  "using the ext4 subsystem");
3751                 else {
3752                         /*
3753                          * If we're probing be silent, if this looks like
3754                          * it's actually an ext4 filesystem.
3755                          */
3756                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3757                                 goto failed_mount;
3758                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3759                                  "to feature incompatibilities");
3760                         goto failed_mount;
3761                 }
3762         }
3763
3764         /*
3765          * Check feature flags regardless of the revision level, since we
3766          * previously didn't change the revision level when setting the flags,
3767          * so there is a chance incompat flags are set on a rev 0 filesystem.
3768          */
3769         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3770                 goto failed_mount;
3771
3772         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3773         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3774             blocksize > EXT4_MAX_BLOCK_SIZE) {
3775                 ext4_msg(sb, KERN_ERR,
3776                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3777                          blocksize, le32_to_cpu(es->s_log_block_size));
3778                 goto failed_mount;
3779         }
3780         if (le32_to_cpu(es->s_log_block_size) >
3781             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3782                 ext4_msg(sb, KERN_ERR,
3783                          "Invalid log block size: %u",
3784                          le32_to_cpu(es->s_log_block_size));
3785                 goto failed_mount;
3786         }
3787
3788         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3789                 ext4_msg(sb, KERN_ERR,
3790                          "Number of reserved GDT blocks insanely large: %d",
3791                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3792                 goto failed_mount;
3793         }
3794
3795         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3796                 if (ext4_has_feature_inline_data(sb)) {
3797                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3798                                         " that may contain inline data");
3799                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3800                 }
3801                 err = bdev_dax_supported(sb, blocksize);
3802                 if (err) {
3803                         ext4_msg(sb, KERN_ERR,
3804                                 "DAX unsupported by block device. Turning off DAX.");
3805                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3806                 }
3807         }
3808
3809         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3810                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3811                          es->s_encryption_level);
3812                 goto failed_mount;
3813         }
3814
3815         if (sb->s_blocksize != blocksize) {
3816                 /* Validate the filesystem blocksize */
3817                 if (!sb_set_blocksize(sb, blocksize)) {
3818                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3819                                         blocksize);
3820                         goto failed_mount;
3821                 }
3822
3823                 brelse(bh);
3824                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3825                 offset = do_div(logical_sb_block, blocksize);
3826                 bh = sb_bread_unmovable(sb, logical_sb_block);
3827                 if (!bh) {
3828                         ext4_msg(sb, KERN_ERR,
3829                                "Can't read superblock on 2nd try");
3830                         goto failed_mount;
3831                 }
3832                 es = (struct ext4_super_block *)(bh->b_data + offset);
3833                 sbi->s_es = es;
3834                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3835                         ext4_msg(sb, KERN_ERR,
3836                                "Magic mismatch, very weird!");
3837                         goto failed_mount;
3838                 }
3839         }
3840
3841         has_huge_files = ext4_has_feature_huge_file(sb);
3842         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3843                                                       has_huge_files);
3844         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3845
3846         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3847                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3848                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3849         } else {
3850                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3851                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3852                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3853                     (!is_power_of_2(sbi->s_inode_size)) ||
3854                     (sbi->s_inode_size > blocksize)) {
3855                         ext4_msg(sb, KERN_ERR,
3856                                "unsupported inode size: %d",
3857                                sbi->s_inode_size);
3858                         goto failed_mount;
3859                 }
3860                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3861                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3862         }
3863
3864         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3865         if (ext4_has_feature_64bit(sb)) {
3866                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3867                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3868                     !is_power_of_2(sbi->s_desc_size)) {
3869                         ext4_msg(sb, KERN_ERR,
3870                                "unsupported descriptor size %lu",
3871                                sbi->s_desc_size);
3872                         goto failed_mount;
3873                 }
3874         } else
3875                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3876
3877         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3878         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3879
3880         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3881         if (sbi->s_inodes_per_block == 0)
3882                 goto cantfind_ext4;
3883         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
3884             sbi->s_inodes_per_group > blocksize * 8) {
3885                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
3886                          sbi->s_blocks_per_group);
3887                 goto failed_mount;
3888         }
3889         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3890                                         sbi->s_inodes_per_block;
3891         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3892         sbi->s_sbh = bh;
3893         sbi->s_mount_state = le16_to_cpu(es->s_state);
3894         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3895         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3896
3897         for (i = 0; i < 4; i++)
3898                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3899         sbi->s_def_hash_version = es->s_def_hash_version;
3900         if (ext4_has_feature_dir_index(sb)) {
3901                 i = le32_to_cpu(es->s_flags);
3902                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3903                         sbi->s_hash_unsigned = 3;
3904                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3905 #ifdef __CHAR_UNSIGNED__
3906                         if (!sb_rdonly(sb))
3907                                 es->s_flags |=
3908                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3909                         sbi->s_hash_unsigned = 3;
3910 #else
3911                         if (!sb_rdonly(sb))
3912                                 es->s_flags |=
3913                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3914 #endif
3915                 }
3916         }
3917
3918         /* Handle clustersize */
3919         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3920         has_bigalloc = ext4_has_feature_bigalloc(sb);
3921         if (has_bigalloc) {
3922                 if (clustersize < blocksize) {
3923                         ext4_msg(sb, KERN_ERR,
3924                                  "cluster size (%d) smaller than "
3925                                  "block size (%d)", clustersize, blocksize);
3926                         goto failed_mount;
3927                 }
3928                 if (le32_to_cpu(es->s_log_cluster_size) >
3929                     (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3930                         ext4_msg(sb, KERN_ERR,
3931                                  "Invalid log cluster size: %u",
3932                                  le32_to_cpu(es->s_log_cluster_size));
3933                         goto failed_mount;
3934                 }
3935                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3936                         le32_to_cpu(es->s_log_block_size);
3937                 sbi->s_clusters_per_group =
3938                         le32_to_cpu(es->s_clusters_per_group);
3939                 if (sbi->s_clusters_per_group > blocksize * 8) {
3940                         ext4_msg(sb, KERN_ERR,
3941                                  "#clusters per group too big: %lu",
3942                                  sbi->s_clusters_per_group);
3943                         goto failed_mount;
3944                 }
3945                 if (sbi->s_blocks_per_group !=
3946                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3947                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3948                                  "clusters per group (%lu) inconsistent",
3949                                  sbi->s_blocks_per_group,
3950                                  sbi->s_clusters_per_group);
3951                         goto failed_mount;
3952                 }
3953         } else {
3954                 if (clustersize != blocksize) {
3955                         ext4_warning(sb, "fragment/cluster size (%d) != "
3956                                      "block size (%d)", clustersize,
3957                                      blocksize);
3958                         clustersize = blocksize;
3959                 }
3960                 if (sbi->s_blocks_per_group > blocksize * 8) {
3961                         ext4_msg(sb, KERN_ERR,
3962                                  "#blocks per group too big: %lu",
3963                                  sbi->s_blocks_per_group);
3964                         goto failed_mount;
3965                 }
3966                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3967                 sbi->s_cluster_bits = 0;
3968         }
3969         sbi->s_cluster_ratio = clustersize / blocksize;
3970
3971         /* Do we have standard group size of clustersize * 8 blocks ? */
3972         if (sbi->s_blocks_per_group == clustersize << 3)
3973                 set_opt2(sb, STD_GROUP_SIZE);
3974
3975         /*
3976          * Test whether we have more sectors than will fit in sector_t,
3977          * and whether the max offset is addressable by the page cache.
3978          */
3979         err = generic_check_addressable(sb->s_blocksize_bits,
3980                                         ext4_blocks_count(es));
3981         if (err) {
3982                 ext4_msg(sb, KERN_ERR, "filesystem"
3983                          " too large to mount safely on this system");
3984                 if (sizeof(sector_t) < 8)
3985                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3986                 goto failed_mount;
3987         }
3988
3989         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3990                 goto cantfind_ext4;
3991
3992         /* check blocks count against device size */
3993         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3994         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3995                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3996                        "exceeds size of device (%llu blocks)",
3997                        ext4_blocks_count(es), blocks_count);
3998                 goto failed_mount;
3999         }
4000
4001         /*
4002          * It makes no sense for the first data block to be beyond the end
4003          * of the filesystem.
4004          */
4005         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4006                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4007                          "block %u is beyond end of filesystem (%llu)",
4008                          le32_to_cpu(es->s_first_data_block),
4009                          ext4_blocks_count(es));
4010                 goto failed_mount;
4011         }
4012         blocks_count = (ext4_blocks_count(es) -
4013                         le32_to_cpu(es->s_first_data_block) +
4014                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4015         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4016         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4017                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
4018                        "(block count %llu, first data block %u, "
4019                        "blocks per group %lu)", sbi->s_groups_count,
4020                        ext4_blocks_count(es),
4021                        le32_to_cpu(es->s_first_data_block),
4022                        EXT4_BLOCKS_PER_GROUP(sb));
4023                 goto failed_mount;
4024         }
4025         sbi->s_groups_count = blocks_count;
4026         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4027                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4028         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4029                    EXT4_DESC_PER_BLOCK(sb);
4030         if (ext4_has_feature_meta_bg(sb)) {
4031                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4032                         ext4_msg(sb, KERN_WARNING,
4033                                  "first meta block group too large: %u "
4034                                  "(group descriptor block count %u)",
4035                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4036                         goto failed_mount;
4037                 }
4038         }
4039         sbi->s_group_desc = kvmalloc(db_count *
4040                                           sizeof(struct buffer_head *),
4041                                           GFP_KERNEL);
4042         if (sbi->s_group_desc == NULL) {
4043                 ext4_msg(sb, KERN_ERR, "not enough memory");
4044                 ret = -ENOMEM;
4045                 goto failed_mount;
4046         }
4047
4048         bgl_lock_init(sbi->s_blockgroup_lock);
4049
4050         /* Pre-read the descriptors into the buffer cache */
4051         for (i = 0; i < db_count; i++) {
4052                 block = descriptor_loc(sb, logical_sb_block, i);
4053                 sb_breadahead(sb, block);
4054         }
4055
4056         for (i = 0; i < db_count; i++) {
4057                 block = descriptor_loc(sb, logical_sb_block, i);
4058                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
4059                 if (!sbi->s_group_desc[i]) {
4060                         ext4_msg(sb, KERN_ERR,
4061                                "can't read group descriptor %d", i);
4062                         db_count = i;
4063                         goto failed_mount2;
4064                 }
4065         }
4066         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4067                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4068                 ret = -EFSCORRUPTED;
4069                 goto failed_mount2;
4070         }
4071
4072         sbi->s_gdb_count = db_count;
4073
4074         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4075
4076         /* Register extent status tree shrinker */
4077         if (ext4_es_register_shrinker(sbi))
4078                 goto failed_mount3;
4079
4080         sbi->s_stripe = ext4_get_stripe_size(sbi);
4081         sbi->s_extent_max_zeroout_kb = 32;
4082
4083         /*
4084          * set up enough so that it can read an inode
4085          */
4086         sb->s_op = &ext4_sops;
4087         sb->s_export_op = &ext4_export_ops;
4088         sb->s_xattr = ext4_xattr_handlers;
4089 #ifdef CONFIG_EXT4_FS_ENCRYPTION
4090         sb->s_cop = &ext4_cryptops;
4091 #endif
4092 #ifdef CONFIG_QUOTA
4093         sb->dq_op = &ext4_quota_operations;
4094         if (ext4_has_feature_quota(sb))
4095                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4096         else
4097                 sb->s_qcop = &ext4_qctl_operations;
4098         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4099 #endif
4100         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4101
4102         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4103         mutex_init(&sbi->s_orphan_lock);
4104
4105         sb->s_root = NULL;
4106
4107         needs_recovery = (es->s_last_orphan != 0 ||
4108                           ext4_has_feature_journal_needs_recovery(sb));
4109
4110         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4111                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4112                         goto failed_mount3a;
4113
4114         /*
4115          * The first inode we look at is the journal inode.  Don't try
4116          * root first: it may be modified in the journal!
4117          */
4118         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4119                 err = ext4_load_journal(sb, es, journal_devnum);
4120                 if (err)
4121                         goto failed_mount3a;
4122         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4123                    ext4_has_feature_journal_needs_recovery(sb)) {
4124                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4125                        "suppressed and not mounted read-only");
4126                 goto failed_mount_wq;
4127         } else {
4128                 /* Nojournal mode, all journal mount options are illegal */
4129                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4130                         ext4_msg(sb, KERN_ERR, "can't mount with "
4131                                  "journal_checksum, fs mounted w/o journal");
4132                         goto failed_mount_wq;
4133                 }
4134                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4135                         ext4_msg(sb, KERN_ERR, "can't mount with "
4136                                  "journal_async_commit, fs mounted w/o journal");
4137                         goto failed_mount_wq;
4138                 }
4139                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4140                         ext4_msg(sb, KERN_ERR, "can't mount with "
4141                                  "commit=%lu, fs mounted w/o journal",
4142                                  sbi->s_commit_interval / HZ);
4143                         goto failed_mount_wq;
4144                 }
4145                 if (EXT4_MOUNT_DATA_FLAGS &
4146                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4147                         ext4_msg(sb, KERN_ERR, "can't mount with "
4148                                  "data=, fs mounted w/o journal");
4149                         goto failed_mount_wq;
4150                 }
4151                 sbi->s_def_mount_opt &= EXT4_MOUNT_JOURNAL_CHECKSUM;
4152                 clear_opt(sb, JOURNAL_CHECKSUM);
4153                 clear_opt(sb, DATA_FLAGS);
4154                 sbi->s_journal = NULL;
4155                 needs_recovery = 0;
4156                 goto no_journal;
4157         }
4158
4159         if (ext4_has_feature_64bit(sb) &&
4160             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4161                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4162                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4163                 goto failed_mount_wq;
4164         }
4165
4166         if (!set_journal_csum_feature_set(sb)) {
4167                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4168                          "feature set");
4169                 goto failed_mount_wq;
4170         }
4171
4172         /* We have now updated the journal if required, so we can
4173          * validate the data journaling mode. */
4174         switch (test_opt(sb, DATA_FLAGS)) {
4175         case 0:
4176                 /* No mode set, assume a default based on the journal
4177                  * capabilities: ORDERED_DATA if the journal can
4178                  * cope, else JOURNAL_DATA
4179                  */
4180                 if (jbd2_journal_check_available_features
4181                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4182                         set_opt(sb, ORDERED_DATA);
4183                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4184                 } else {
4185                         set_opt(sb, JOURNAL_DATA);
4186                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4187                 }
4188                 break;
4189
4190         case EXT4_MOUNT_ORDERED_DATA:
4191         case EXT4_MOUNT_WRITEBACK_DATA:
4192                 if (!jbd2_journal_check_available_features
4193                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4194                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4195                                "requested data journaling mode");
4196                         goto failed_mount_wq;
4197                 }
4198         default:
4199                 break;
4200         }
4201
4202         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4203             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4204                 ext4_msg(sb, KERN_ERR, "can't mount with "
4205                         "journal_async_commit in data=ordered mode");
4206                 goto failed_mount_wq;
4207         }
4208
4209         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4210
4211         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4212
4213 no_journal:
4214         if (!test_opt(sb, NO_MBCACHE)) {
4215                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4216                 if (!sbi->s_ea_block_cache) {
4217                         ext4_msg(sb, KERN_ERR,
4218                                  "Failed to create ea_block_cache");
4219                         goto failed_mount_wq;
4220                 }
4221
4222                 if (ext4_has_feature_ea_inode(sb)) {
4223                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4224                         if (!sbi->s_ea_inode_cache) {
4225                                 ext4_msg(sb, KERN_ERR,
4226                                          "Failed to create ea_inode_cache");
4227                                 goto failed_mount_wq;
4228                         }
4229                 }
4230         }
4231
4232         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4233             (blocksize != PAGE_SIZE)) {
4234                 ext4_msg(sb, KERN_ERR,
4235                          "Unsupported blocksize for fs encryption");
4236                 goto failed_mount_wq;
4237         }
4238
4239         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4240             !ext4_has_feature_encrypt(sb)) {
4241                 ext4_set_feature_encrypt(sb);
4242                 ext4_commit_super(sb, 1);
4243         }
4244
4245         /*
4246          * Get the # of file system overhead blocks from the
4247          * superblock if present.
4248          */
4249         if (es->s_overhead_clusters)
4250                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4251         else {
4252                 err = ext4_calculate_overhead(sb);
4253                 if (err)
4254                         goto failed_mount_wq;
4255         }
4256
4257         /*
4258          * The maximum number of concurrent works can be high and
4259          * concurrency isn't really necessary.  Limit it to 1.
4260          */
4261         EXT4_SB(sb)->rsv_conversion_wq =
4262                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4263         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4264                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4265                 ret = -ENOMEM;
4266                 goto failed_mount4;
4267         }
4268
4269         /*
4270          * The jbd2_journal_load will have done any necessary log recovery,
4271          * so we can safely mount the rest of the filesystem now.
4272          */
4273
4274         root = ext4_iget(sb, EXT4_ROOT_INO);
4275         if (IS_ERR(root)) {
4276                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4277                 ret = PTR_ERR(root);
4278                 root = NULL;
4279                 goto failed_mount4;
4280         }
4281         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4282                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4283                 iput(root);
4284                 goto failed_mount4;
4285         }
4286         sb->s_root = d_make_root(root);
4287         if (!sb->s_root) {
4288                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4289                 ret = -ENOMEM;
4290                 goto failed_mount4;
4291         }
4292
4293         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4294         if (ret == -EROFS) {
4295                 sb->s_flags |= SB_RDONLY;
4296                 ret = 0;
4297         } else if (ret)
4298                 goto failed_mount4a;
4299
4300         /* determine the minimum size of new large inodes, if present */
4301         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE &&
4302             sbi->s_want_extra_isize == 0) {
4303                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4304                                                      EXT4_GOOD_OLD_INODE_SIZE;
4305                 if (ext4_has_feature_extra_isize(sb)) {
4306                         if (sbi->s_want_extra_isize <
4307                             le16_to_cpu(es->s_want_extra_isize))
4308                                 sbi->s_want_extra_isize =
4309                                         le16_to_cpu(es->s_want_extra_isize);
4310                         if (sbi->s_want_extra_isize <
4311                             le16_to_cpu(es->s_min_extra_isize))
4312                                 sbi->s_want_extra_isize =
4313                                         le16_to_cpu(es->s_min_extra_isize);
4314                 }
4315         }
4316         /* Check if enough inode space is available */
4317         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4318                                                         sbi->s_inode_size) {
4319                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4320                                                        EXT4_GOOD_OLD_INODE_SIZE;
4321                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4322                          "available");
4323         }
4324
4325         ext4_set_resv_clusters(sb);
4326
4327         err = ext4_setup_system_zone(sb);
4328         if (err) {
4329                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4330                          "zone (%d)", err);
4331                 goto failed_mount4a;
4332         }
4333
4334         ext4_ext_init(sb);
4335         err = ext4_mb_init(sb);
4336         if (err) {
4337                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4338                          err);
4339                 goto failed_mount5;
4340         }
4341
4342         block = ext4_count_free_clusters(sb);
4343         ext4_free_blocks_count_set(sbi->s_es,
4344                                    EXT4_C2B(sbi, block));
4345         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4346                                   GFP_KERNEL);
4347         if (!err) {
4348                 unsigned long freei = ext4_count_free_inodes(sb);
4349                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4350                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4351                                           GFP_KERNEL);
4352         }
4353         if (!err)
4354                 err = percpu_counter_init(&sbi->s_dirs_counter,
4355                                           ext4_count_dirs(sb), GFP_KERNEL);
4356         if (!err)
4357                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4358                                           GFP_KERNEL);
4359         if (!err)
4360                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4361
4362         if (err) {
4363                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4364                 goto failed_mount6;
4365         }
4366
4367         if (ext4_has_feature_flex_bg(sb))
4368                 if (!ext4_fill_flex_info(sb)) {
4369                         ext4_msg(sb, KERN_ERR,
4370                                "unable to initialize "
4371                                "flex_bg meta info!");
4372                         goto failed_mount6;
4373                 }
4374
4375         err = ext4_register_li_request(sb, first_not_zeroed);
4376         if (err)
4377                 goto failed_mount6;
4378
4379         err = ext4_register_sysfs(sb);
4380         if (err)
4381                 goto failed_mount7;
4382
4383 #ifdef CONFIG_QUOTA
4384         /* Enable quota usage during mount. */
4385         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4386                 err = ext4_enable_quotas(sb);
4387                 if (err)
4388                         goto failed_mount8;
4389         }
4390 #endif  /* CONFIG_QUOTA */
4391
4392         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4393         ext4_orphan_cleanup(sb, es);
4394         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4395         if (needs_recovery) {
4396                 ext4_msg(sb, KERN_INFO, "recovery complete");
4397                 ext4_mark_recovery_complete(sb, es);
4398         }
4399         if (EXT4_SB(sb)->s_journal) {
4400                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4401                         descr = " journalled data mode";
4402                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4403                         descr = " ordered data mode";
4404                 else
4405                         descr = " writeback data mode";
4406         } else
4407                 descr = "out journal";
4408
4409         if (test_opt(sb, DISCARD)) {
4410                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4411                 if (!blk_queue_discard(q))
4412                         ext4_msg(sb, KERN_WARNING,
4413                                  "mounting with \"discard\" option, but "
4414                                  "the device does not support discard");
4415         }
4416
4417         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4418                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4419                          "Opts: %.*s%s%s", descr,
4420                          (int) sizeof(sbi->s_es->s_mount_opts),
4421                          sbi->s_es->s_mount_opts,
4422                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4423
4424         if (es->s_error_count)
4425                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4426
4427         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4428         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4429         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4430         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4431
4432         kfree(orig_data);
4433         return 0;
4434
4435 cantfind_ext4:
4436         if (!silent)
4437                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4438         goto failed_mount;
4439
4440 #ifdef CONFIG_QUOTA
4441 failed_mount8:
4442         ext4_unregister_sysfs(sb);
4443 #endif
4444 failed_mount7:
4445         ext4_unregister_li_request(sb);
4446 failed_mount6:
4447         ext4_mb_release(sb);
4448         if (sbi->s_flex_groups)
4449                 kvfree(sbi->s_flex_groups);
4450         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4451         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4452         percpu_counter_destroy(&sbi->s_dirs_counter);
4453         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4454 failed_mount5:
4455         ext4_ext_release(sb);
4456         ext4_release_system_zone(sb);
4457 failed_mount4a:
4458         dput(sb->s_root);
4459         sb->s_root = NULL;
4460 failed_mount4:
4461         ext4_msg(sb, KERN_ERR, "mount failed");
4462         if (EXT4_SB(sb)->rsv_conversion_wq)
4463                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4464 failed_mount_wq:
4465         if (sbi->s_ea_inode_cache) {
4466                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4467                 sbi->s_ea_inode_cache = NULL;
4468         }
4469         if (sbi->s_ea_block_cache) {
4470                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4471                 sbi->s_ea_block_cache = NULL;
4472         }
4473         if (sbi->s_journal) {
4474                 jbd2_journal_destroy(sbi->s_journal);
4475                 sbi->s_journal = NULL;
4476         }
4477 failed_mount3a:
4478         ext4_es_unregister_shrinker(sbi);
4479 failed_mount3:
4480         del_timer_sync(&sbi->s_err_report);
4481         if (sbi->s_mmp_tsk)
4482                 kthread_stop(sbi->s_mmp_tsk);
4483 failed_mount2:
4484         for (i = 0; i < db_count; i++)
4485                 brelse(sbi->s_group_desc[i]);
4486         kvfree(sbi->s_group_desc);
4487 failed_mount:
4488         if (sbi->s_chksum_driver)
4489                 crypto_free_shash(sbi->s_chksum_driver);
4490 #ifdef CONFIG_QUOTA
4491         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4492                 kfree(sbi->s_qf_names[i]);
4493 #endif
4494         ext4_blkdev_remove(sbi);
4495         brelse(bh);
4496 out_fail:
4497         sb->s_fs_info = NULL;
4498         kfree(sbi->s_blockgroup_lock);
4499 out_free_base:
4500         kfree(sbi);
4501         kfree(orig_data);
4502         fs_put_dax(dax_dev);
4503         return err ? err : ret;
4504 }
4505
4506 /*
4507  * Setup any per-fs journal parameters now.  We'll do this both on
4508  * initial mount, once the journal has been initialised but before we've
4509  * done any recovery; and again on any subsequent remount.
4510  */
4511 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4512 {
4513         struct ext4_sb_info *sbi = EXT4_SB(sb);
4514
4515         journal->j_commit_interval = sbi->s_commit_interval;
4516         journal->j_min_batch_time = sbi->s_min_batch_time;
4517         journal->j_max_batch_time = sbi->s_max_batch_time;
4518
4519         write_lock(&journal->j_state_lock);
4520         if (test_opt(sb, BARRIER))
4521                 journal->j_flags |= JBD2_BARRIER;
4522         else
4523                 journal->j_flags &= ~JBD2_BARRIER;
4524         if (test_opt(sb, DATA_ERR_ABORT))
4525                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4526         else
4527                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4528         write_unlock(&journal->j_state_lock);
4529 }
4530
4531 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4532                                              unsigned int journal_inum)
4533 {
4534         struct inode *journal_inode;
4535
4536         /*
4537          * Test for the existence of a valid inode on disk.  Bad things
4538          * happen if we iget() an unused inode, as the subsequent iput()
4539          * will try to delete it.
4540          */
4541         journal_inode = ext4_iget(sb, journal_inum);
4542         if (IS_ERR(journal_inode)) {
4543                 ext4_msg(sb, KERN_ERR, "no journal found");
4544                 return NULL;
4545         }
4546         if (!journal_inode->i_nlink) {
4547                 make_bad_inode(journal_inode);
4548                 iput(journal_inode);
4549                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4550                 return NULL;
4551         }
4552
4553         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4554                   journal_inode, journal_inode->i_size);
4555         if (!S_ISREG(journal_inode->i_mode)) {
4556                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4557                 iput(journal_inode);
4558                 return NULL;
4559         }
4560         return journal_inode;
4561 }
4562
4563 static journal_t *ext4_get_journal(struct super_block *sb,
4564                                    unsigned int journal_inum)
4565 {
4566         struct inode *journal_inode;
4567         journal_t *journal;
4568
4569         BUG_ON(!ext4_has_feature_journal(sb));
4570
4571         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4572         if (!journal_inode)
4573                 return NULL;
4574
4575         journal = jbd2_journal_init_inode(journal_inode);
4576         if (!journal) {
4577                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4578                 iput(journal_inode);
4579                 return NULL;
4580         }
4581         journal->j_private = sb;
4582         ext4_init_journal_params(sb, journal);
4583         return journal;
4584 }
4585
4586 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4587                                        dev_t j_dev)
4588 {
4589         struct buffer_head *bh;
4590         journal_t *journal;
4591         ext4_fsblk_t start;
4592         ext4_fsblk_t len;
4593         int hblock, blocksize;
4594         ext4_fsblk_t sb_block;
4595         unsigned long offset;
4596         struct ext4_super_block *es;
4597         struct block_device *bdev;
4598
4599         BUG_ON(!ext4_has_feature_journal(sb));
4600
4601         bdev = ext4_blkdev_get(j_dev, sb);
4602         if (bdev == NULL)
4603                 return NULL;
4604
4605         blocksize = sb->s_blocksize;
4606         hblock = bdev_logical_block_size(bdev);
4607         if (blocksize < hblock) {
4608                 ext4_msg(sb, KERN_ERR,
4609                         "blocksize too small for journal device");
4610                 goto out_bdev;
4611         }
4612
4613         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4614         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4615         set_blocksize(bdev, blocksize);
4616         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4617                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4618                        "external journal");
4619                 goto out_bdev;
4620         }
4621
4622         es = (struct ext4_super_block *) (bh->b_data + offset);
4623         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4624             !(le32_to_cpu(es->s_feature_incompat) &
4625               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4626                 ext4_msg(sb, KERN_ERR, "external journal has "
4627                                         "bad superblock");
4628                 brelse(bh);
4629                 goto out_bdev;
4630         }
4631
4632         if ((le32_to_cpu(es->s_feature_ro_compat) &
4633              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4634             es->s_checksum != ext4_superblock_csum(sb, es)) {
4635                 ext4_msg(sb, KERN_ERR, "external journal has "
4636                                        "corrupt superblock");
4637                 brelse(bh);
4638                 goto out_bdev;
4639         }
4640
4641         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4642                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4643                 brelse(bh);
4644                 goto out_bdev;
4645         }
4646
4647         len = ext4_blocks_count(es);
4648         start = sb_block + 1;
4649         brelse(bh);     /* we're done with the superblock */
4650
4651         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4652                                         start, len, blocksize);
4653         if (!journal) {
4654                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4655                 goto out_bdev;
4656         }
4657         journal->j_private = sb;
4658         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4659         wait_on_buffer(journal->j_sb_buffer);
4660         if (!buffer_uptodate(journal->j_sb_buffer)) {
4661                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4662                 goto out_journal;
4663         }
4664         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4665                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4666                                         "user (unsupported) - %d",
4667                         be32_to_cpu(journal->j_superblock->s_nr_users));
4668                 goto out_journal;
4669         }
4670         EXT4_SB(sb)->journal_bdev = bdev;
4671         ext4_init_journal_params(sb, journal);
4672         return journal;
4673
4674 out_journal:
4675         jbd2_journal_destroy(journal);
4676 out_bdev:
4677         ext4_blkdev_put(bdev);
4678         return NULL;
4679 }
4680
4681 static int ext4_load_journal(struct super_block *sb,
4682                              struct ext4_super_block *es,
4683                              unsigned long journal_devnum)
4684 {
4685         journal_t *journal;
4686         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4687         dev_t journal_dev;
4688         int err = 0;
4689         int really_read_only;
4690
4691         BUG_ON(!ext4_has_feature_journal(sb));
4692
4693         if (journal_devnum &&
4694             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4695                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4696                         "numbers have changed");
4697                 journal_dev = new_decode_dev(journal_devnum);
4698         } else
4699                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4700
4701         really_read_only = bdev_read_only(sb->s_bdev);
4702
4703         /*
4704          * Are we loading a blank journal or performing recovery after a
4705          * crash?  For recovery, we need to check in advance whether we
4706          * can get read-write access to the device.
4707          */
4708         if (ext4_has_feature_journal_needs_recovery(sb)) {
4709                 if (sb_rdonly(sb)) {
4710                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4711                                         "required on readonly filesystem");
4712                         if (really_read_only) {
4713                                 ext4_msg(sb, KERN_ERR, "write access "
4714                                         "unavailable, cannot proceed "
4715                                         "(try mounting with noload)");
4716                                 return -EROFS;
4717                         }
4718                         ext4_msg(sb, KERN_INFO, "write access will "
4719                                "be enabled during recovery");
4720                 }
4721         }
4722
4723         if (journal_inum && journal_dev) {
4724                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4725                        "and inode journals!");
4726                 return -EINVAL;
4727         }
4728
4729         if (journal_inum) {
4730                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4731                         return -EINVAL;
4732         } else {
4733                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4734                         return -EINVAL;
4735         }
4736
4737         if (!(journal->j_flags & JBD2_BARRIER))
4738                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4739
4740         if (!ext4_has_feature_journal_needs_recovery(sb))
4741                 err = jbd2_journal_wipe(journal, !really_read_only);
4742         if (!err) {
4743                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4744                 if (save)
4745                         memcpy(save, ((char *) es) +
4746                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4747                 err = jbd2_journal_load(journal);
4748                 if (save)
4749                         memcpy(((char *) es) + EXT4_S_ERR_START,
4750                                save, EXT4_S_ERR_LEN);
4751                 kfree(save);
4752         }
4753
4754         if (err) {
4755                 ext4_msg(sb, KERN_ERR, "error loading journal");
4756                 jbd2_journal_destroy(journal);
4757                 return err;
4758         }
4759
4760         EXT4_SB(sb)->s_journal = journal;
4761         ext4_clear_journal_err(sb, es);
4762
4763         if (!really_read_only && journal_devnum &&
4764             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4765                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4766
4767                 /* Make sure we flush the recovery flag to disk. */
4768                 ext4_commit_super(sb, 1);
4769         }
4770
4771         return 0;
4772 }
4773
4774 static int ext4_commit_super(struct super_block *sb, int sync)
4775 {
4776         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4777         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4778         int error = 0;
4779
4780         if (!sbh || block_device_ejected(sb))
4781                 return error;
4782         /*
4783          * If the file system is mounted read-only, don't update the
4784          * superblock write time.  This avoids updating the superblock
4785          * write time when we are mounting the root file system
4786          * read/only but we need to replay the journal; at that point,
4787          * for people who are east of GMT and who make their clock
4788          * tick in localtime for Windows bug-for-bug compatibility,
4789          * the clock is set in the future, and this will cause e2fsck
4790          * to complain and force a full file system check.
4791          */
4792         if (!(sb->s_flags & SB_RDONLY))
4793                 es->s_wtime = cpu_to_le32(get_seconds());
4794         if (sb->s_bdev->bd_part)
4795                 es->s_kbytes_written =
4796                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4797                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4798                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4799         else
4800                 es->s_kbytes_written =
4801                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4802         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4803                 ext4_free_blocks_count_set(es,
4804                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4805                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4806         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4807                 es->s_free_inodes_count =
4808                         cpu_to_le32(percpu_counter_sum_positive(
4809                                 &EXT4_SB(sb)->s_freeinodes_counter));
4810         BUFFER_TRACE(sbh, "marking dirty");
4811         ext4_superblock_csum_set(sb);
4812         if (sync)
4813                 lock_buffer(sbh);
4814         if (buffer_write_io_error(sbh)) {
4815                 /*
4816                  * Oh, dear.  A previous attempt to write the
4817                  * superblock failed.  This could happen because the
4818                  * USB device was yanked out.  Or it could happen to
4819                  * be a transient write error and maybe the block will
4820                  * be remapped.  Nothing we can do but to retry the
4821                  * write and hope for the best.
4822                  */
4823                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4824                        "superblock detected");
4825                 clear_buffer_write_io_error(sbh);
4826                 set_buffer_uptodate(sbh);
4827         }
4828         mark_buffer_dirty(sbh);
4829         if (sync) {
4830                 unlock_buffer(sbh);
4831                 error = __sync_dirty_buffer(sbh,
4832                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
4833                 if (buffer_write_io_error(sbh)) {
4834                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4835                                "superblock");
4836                         clear_buffer_write_io_error(sbh);
4837                         set_buffer_uptodate(sbh);
4838                 }
4839         }
4840         return error;
4841 }
4842
4843 /*
4844  * Have we just finished recovery?  If so, and if we are mounting (or
4845  * remounting) the filesystem readonly, then we will end up with a
4846  * consistent fs on disk.  Record that fact.
4847  */
4848 static void ext4_mark_recovery_complete(struct super_block *sb,
4849                                         struct ext4_super_block *es)
4850 {
4851         journal_t *journal = EXT4_SB(sb)->s_journal;
4852
4853         if (!ext4_has_feature_journal(sb)) {
4854                 BUG_ON(journal != NULL);
4855                 return;
4856         }
4857         jbd2_journal_lock_updates(journal);
4858         if (jbd2_journal_flush(journal) < 0)
4859                 goto out;
4860
4861         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
4862                 ext4_clear_feature_journal_needs_recovery(sb);
4863                 ext4_commit_super(sb, 1);
4864         }
4865
4866 out:
4867         jbd2_journal_unlock_updates(journal);
4868 }
4869
4870 /*
4871  * If we are mounting (or read-write remounting) a filesystem whose journal
4872  * has recorded an error from a previous lifetime, move that error to the
4873  * main filesystem now.
4874  */
4875 static void ext4_clear_journal_err(struct super_block *sb,
4876                                    struct ext4_super_block *es)
4877 {
4878         journal_t *journal;
4879         int j_errno;
4880         const char *errstr;
4881
4882         BUG_ON(!ext4_has_feature_journal(sb));
4883
4884         journal = EXT4_SB(sb)->s_journal;
4885
4886         /*
4887          * Now check for any error status which may have been recorded in the
4888          * journal by a prior ext4_error() or ext4_abort()
4889          */
4890
4891         j_errno = jbd2_journal_errno(journal);
4892         if (j_errno) {
4893                 char nbuf[16];
4894
4895                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4896                 ext4_warning(sb, "Filesystem error recorded "
4897                              "from previous mount: %s", errstr);
4898                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4899
4900                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4901                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4902                 ext4_commit_super(sb, 1);
4903
4904                 jbd2_journal_clear_err(journal);
4905                 jbd2_journal_update_sb_errno(journal);
4906         }
4907 }
4908
4909 /*
4910  * Force the running and committing transactions to commit,
4911  * and wait on the commit.
4912  */
4913 int ext4_force_commit(struct super_block *sb)
4914 {
4915         journal_t *journal;
4916
4917         if (sb_rdonly(sb))
4918                 return 0;
4919
4920         journal = EXT4_SB(sb)->s_journal;
4921         return ext4_journal_force_commit(journal);
4922 }
4923
4924 static int ext4_sync_fs(struct super_block *sb, int wait)
4925 {
4926         int ret = 0;
4927         tid_t target;
4928         bool needs_barrier = false;
4929         struct ext4_sb_info *sbi = EXT4_SB(sb);
4930
4931         if (unlikely(ext4_forced_shutdown(sbi)))
4932                 return 0;
4933
4934         trace_ext4_sync_fs(sb, wait);
4935         flush_workqueue(sbi->rsv_conversion_wq);
4936         /*
4937          * Writeback quota in non-journalled quota case - journalled quota has
4938          * no dirty dquots
4939          */
4940         dquot_writeback_dquots(sb, -1);
4941         /*
4942          * Data writeback is possible w/o journal transaction, so barrier must
4943          * being sent at the end of the function. But we can skip it if
4944          * transaction_commit will do it for us.
4945          */
4946         if (sbi->s_journal) {
4947                 target = jbd2_get_latest_transaction(sbi->s_journal);
4948                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4949                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4950                         needs_barrier = true;
4951
4952                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4953                         if (wait)
4954                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4955                                                            target);
4956                 }
4957         } else if (wait && test_opt(sb, BARRIER))
4958                 needs_barrier = true;
4959         if (needs_barrier) {
4960                 int err;
4961                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4962                 if (!ret)
4963                         ret = err;
4964         }
4965
4966         return ret;
4967 }
4968
4969 /*
4970  * LVM calls this function before a (read-only) snapshot is created.  This
4971  * gives us a chance to flush the journal completely and mark the fs clean.
4972  *
4973  * Note that only this function cannot bring a filesystem to be in a clean
4974  * state independently. It relies on upper layer to stop all data & metadata
4975  * modifications.
4976  */
4977 static int ext4_freeze(struct super_block *sb)
4978 {
4979         int error = 0;
4980         journal_t *journal;
4981
4982         if (sb_rdonly(sb))
4983                 return 0;
4984
4985         journal = EXT4_SB(sb)->s_journal;
4986
4987         if (journal) {
4988                 /* Now we set up the journal barrier. */
4989                 jbd2_journal_lock_updates(journal);
4990
4991                 /*
4992                  * Don't clear the needs_recovery flag if we failed to
4993                  * flush the journal.
4994                  */
4995                 error = jbd2_journal_flush(journal);
4996                 if (error < 0)
4997                         goto out;
4998
4999                 /* Journal blocked and flushed, clear needs_recovery flag. */
5000                 ext4_clear_feature_journal_needs_recovery(sb);
5001         }
5002
5003         error = ext4_commit_super(sb, 1);
5004 out:
5005         if (journal)
5006                 /* we rely on upper layer to stop further updates */
5007                 jbd2_journal_unlock_updates(journal);
5008         return error;
5009 }
5010
5011 /*
5012  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5013  * flag here, even though the filesystem is not technically dirty yet.
5014  */
5015 static int ext4_unfreeze(struct super_block *sb)
5016 {
5017         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5018                 return 0;
5019
5020         if (EXT4_SB(sb)->s_journal) {
5021                 /* Reset the needs_recovery flag before the fs is unlocked. */
5022                 ext4_set_feature_journal_needs_recovery(sb);
5023         }
5024
5025         ext4_commit_super(sb, 1);
5026         return 0;
5027 }
5028
5029 /*
5030  * Structure to save mount options for ext4_remount's benefit
5031  */
5032 struct ext4_mount_options {
5033         unsigned long s_mount_opt;
5034         unsigned long s_mount_opt2;
5035         kuid_t s_resuid;
5036         kgid_t s_resgid;
5037         unsigned long s_commit_interval;
5038         u32 s_min_batch_time, s_max_batch_time;
5039 #ifdef CONFIG_QUOTA
5040         int s_jquota_fmt;
5041         char *s_qf_names[EXT4_MAXQUOTAS];
5042 #endif
5043 };
5044
5045 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5046 {
5047         struct ext4_super_block *es;
5048         struct ext4_sb_info *sbi = EXT4_SB(sb);
5049         unsigned long old_sb_flags;
5050         struct ext4_mount_options old_opts;
5051         int enable_quota = 0;
5052         ext4_group_t g;
5053         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5054         int err = 0;
5055 #ifdef CONFIG_QUOTA
5056         int i, j;
5057 #endif
5058         char *orig_data = kstrdup(data, GFP_KERNEL);
5059
5060         /* Store the original options */
5061         old_sb_flags = sb->s_flags;
5062         old_opts.s_mount_opt = sbi->s_mount_opt;
5063         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5064         old_opts.s_resuid = sbi->s_resuid;
5065         old_opts.s_resgid = sbi->s_resgid;
5066         old_opts.s_commit_interval = sbi->s_commit_interval;
5067         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5068         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5069 #ifdef CONFIG_QUOTA
5070         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5071         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5072                 if (sbi->s_qf_names[i]) {
5073                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
5074                                                          GFP_KERNEL);
5075                         if (!old_opts.s_qf_names[i]) {
5076                                 for (j = 0; j < i; j++)
5077                                         kfree(old_opts.s_qf_names[j]);
5078                                 kfree(orig_data);
5079                                 return -ENOMEM;
5080                         }
5081                 } else
5082                         old_opts.s_qf_names[i] = NULL;
5083 #endif
5084         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5085                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5086
5087         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5088                 err = -EINVAL;
5089                 goto restore_opts;
5090         }
5091
5092         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5093             test_opt(sb, JOURNAL_CHECKSUM)) {
5094                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5095                          "during remount not supported; ignoring");
5096                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5097         }
5098
5099         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5100                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5101                         ext4_msg(sb, KERN_ERR, "can't mount with "
5102                                  "both data=journal and delalloc");
5103                         err = -EINVAL;
5104                         goto restore_opts;
5105                 }
5106                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5107                         ext4_msg(sb, KERN_ERR, "can't mount with "
5108                                  "both data=journal and dioread_nolock");
5109                         err = -EINVAL;
5110                         goto restore_opts;
5111                 }
5112                 if (test_opt(sb, DAX)) {
5113                         ext4_msg(sb, KERN_ERR, "can't mount with "
5114                                  "both data=journal and dax");
5115                         err = -EINVAL;
5116                         goto restore_opts;
5117                 }
5118         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5119                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5120                         ext4_msg(sb, KERN_ERR, "can't mount with "
5121                                 "journal_async_commit in data=ordered mode");
5122                         err = -EINVAL;
5123                         goto restore_opts;
5124                 }
5125         }
5126
5127         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5128                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5129                 err = -EINVAL;
5130                 goto restore_opts;
5131         }
5132
5133         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5134                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5135                         "dax flag with busy inodes while remounting");
5136                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5137         }
5138
5139         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5140                 ext4_abort(sb, "Abort forced by user");
5141
5142         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5143                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5144
5145         es = sbi->s_es;
5146
5147         if (sbi->s_journal) {
5148                 ext4_init_journal_params(sb, sbi->s_journal);
5149                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5150         }
5151
5152         if (*flags & SB_LAZYTIME)
5153                 sb->s_flags |= SB_LAZYTIME;
5154
5155         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5156                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5157                         err = -EROFS;
5158                         goto restore_opts;
5159                 }
5160
5161                 if (*flags & SB_RDONLY) {
5162                         err = sync_filesystem(sb);
5163                         if (err < 0)
5164                                 goto restore_opts;
5165                         err = dquot_suspend(sb, -1);
5166                         if (err < 0)
5167                                 goto restore_opts;
5168
5169                         /*
5170                          * First of all, the unconditional stuff we have to do
5171                          * to disable replay of the journal when we next remount
5172                          */
5173                         sb->s_flags |= SB_RDONLY;
5174
5175                         /*
5176                          * OK, test if we are remounting a valid rw partition
5177                          * readonly, and if so set the rdonly flag and then
5178                          * mark the partition as valid again.
5179                          */
5180                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5181                             (sbi->s_mount_state & EXT4_VALID_FS))
5182                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5183
5184                         if (sbi->s_journal)
5185                                 ext4_mark_recovery_complete(sb, es);
5186                 } else {
5187                         /* Make sure we can mount this feature set readwrite */
5188                         if (ext4_has_feature_readonly(sb) ||
5189                             !ext4_feature_set_ok(sb, 0)) {
5190                                 err = -EROFS;
5191                                 goto restore_opts;
5192                         }
5193                         /*
5194                          * Make sure the group descriptor checksums
5195                          * are sane.  If they aren't, refuse to remount r/w.
5196                          */
5197                         for (g = 0; g < sbi->s_groups_count; g++) {
5198                                 struct ext4_group_desc *gdp =
5199                                         ext4_get_group_desc(sb, g, NULL);
5200
5201                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5202                                         ext4_msg(sb, KERN_ERR,
5203                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5204                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5205                                                le16_to_cpu(gdp->bg_checksum));
5206                                         err = -EFSBADCRC;
5207                                         goto restore_opts;
5208                                 }
5209                         }
5210
5211                         /*
5212                          * If we have an unprocessed orphan list hanging
5213                          * around from a previously readonly bdev mount,
5214                          * require a full umount/remount for now.
5215                          */
5216                         if (es->s_last_orphan) {
5217                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5218                                        "remount RDWR because of unprocessed "
5219                                        "orphan inode list.  Please "
5220                                        "umount/remount instead");
5221                                 err = -EINVAL;
5222                                 goto restore_opts;
5223                         }
5224
5225                         /*
5226                          * Mounting a RDONLY partition read-write, so reread
5227                          * and store the current valid flag.  (It may have
5228                          * been changed by e2fsck since we originally mounted
5229                          * the partition.)
5230                          */
5231                         if (sbi->s_journal)
5232                                 ext4_clear_journal_err(sb, es);
5233                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5234
5235                         err = ext4_setup_super(sb, es, 0);
5236                         if (err)
5237                                 goto restore_opts;
5238
5239                         sb->s_flags &= ~SB_RDONLY;
5240                         if (ext4_has_feature_mmp(sb))
5241                                 if (ext4_multi_mount_protect(sb,
5242                                                 le64_to_cpu(es->s_mmp_block))) {
5243                                         err = -EROFS;
5244                                         goto restore_opts;
5245                                 }
5246                         enable_quota = 1;
5247                 }
5248         }
5249
5250         /*
5251          * Reinitialize lazy itable initialization thread based on
5252          * current settings
5253          */
5254         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5255                 ext4_unregister_li_request(sb);
5256         else {
5257                 ext4_group_t first_not_zeroed;
5258                 first_not_zeroed = ext4_has_uninit_itable(sb);
5259                 ext4_register_li_request(sb, first_not_zeroed);
5260         }
5261
5262         ext4_setup_system_zone(sb);
5263         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5264                 err = ext4_commit_super(sb, 1);
5265                 if (err)
5266                         goto restore_opts;
5267         }
5268
5269 #ifdef CONFIG_QUOTA
5270         /* Release old quota file names */
5271         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5272                 kfree(old_opts.s_qf_names[i]);
5273         if (enable_quota) {
5274                 if (sb_any_quota_suspended(sb))
5275                         dquot_resume(sb, -1);
5276                 else if (ext4_has_feature_quota(sb)) {
5277                         err = ext4_enable_quotas(sb);
5278                         if (err)
5279                                 goto restore_opts;
5280                 }
5281         }
5282 #endif
5283
5284         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5285         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5286         kfree(orig_data);
5287         return 0;
5288
5289 restore_opts:
5290         sb->s_flags = old_sb_flags;
5291         sbi->s_mount_opt = old_opts.s_mount_opt;
5292         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5293         sbi->s_resuid = old_opts.s_resuid;
5294         sbi->s_resgid = old_opts.s_resgid;
5295         sbi->s_commit_interval = old_opts.s_commit_interval;
5296         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5297         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5298 #ifdef CONFIG_QUOTA
5299         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5300         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5301                 kfree(sbi->s_qf_names[i]);
5302                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5303         }
5304 #endif
5305         kfree(orig_data);
5306         return err;
5307 }
5308
5309 #ifdef CONFIG_QUOTA
5310 static int ext4_statfs_project(struct super_block *sb,
5311                                kprojid_t projid, struct kstatfs *buf)
5312 {
5313         struct kqid qid;
5314         struct dquot *dquot;
5315         u64 limit;
5316         u64 curblock;
5317
5318         qid = make_kqid_projid(projid);
5319         dquot = dqget(sb, qid);
5320         if (IS_ERR(dquot))
5321                 return PTR_ERR(dquot);
5322         spin_lock(&dquot->dq_dqb_lock);
5323
5324         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5325                  dquot->dq_dqb.dqb_bsoftlimit :
5326                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5327         if (limit && buf->f_blocks > limit) {
5328                 curblock = (dquot->dq_dqb.dqb_curspace +
5329                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5330                 buf->f_blocks = limit;
5331                 buf->f_bfree = buf->f_bavail =
5332                         (buf->f_blocks > curblock) ?
5333                          (buf->f_blocks - curblock) : 0;
5334         }
5335
5336         limit = dquot->dq_dqb.dqb_isoftlimit ?
5337                 dquot->dq_dqb.dqb_isoftlimit :
5338                 dquot->dq_dqb.dqb_ihardlimit;
5339         if (limit && buf->f_files > limit) {
5340                 buf->f_files = limit;
5341                 buf->f_ffree =
5342                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5343                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5344         }
5345
5346         spin_unlock(&dquot->dq_dqb_lock);
5347         dqput(dquot);
5348         return 0;
5349 }
5350 #endif
5351
5352 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5353 {
5354         struct super_block *sb = dentry->d_sb;
5355         struct ext4_sb_info *sbi = EXT4_SB(sb);
5356         struct ext4_super_block *es = sbi->s_es;
5357         ext4_fsblk_t overhead = 0, resv_blocks;
5358         u64 fsid;
5359         s64 bfree;
5360         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5361
5362         if (!test_opt(sb, MINIX_DF))
5363                 overhead = sbi->s_overhead;
5364
5365         buf->f_type = EXT4_SUPER_MAGIC;
5366         buf->f_bsize = sb->s_blocksize;
5367         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5368         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5369                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5370         /* prevent underflow in case that few free space is available */
5371         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5372         buf->f_bavail = buf->f_bfree -
5373                         (ext4_r_blocks_count(es) + resv_blocks);
5374         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5375                 buf->f_bavail = 0;
5376         buf->f_files = le32_to_cpu(es->s_inodes_count);
5377         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5378         buf->f_namelen = EXT4_NAME_LEN;
5379         fsid = le64_to_cpup((void *)es->s_uuid) ^
5380                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5381         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5382         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5383
5384 #ifdef CONFIG_QUOTA
5385         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5386             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5387                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5388 #endif
5389         return 0;
5390 }
5391
5392
5393 #ifdef CONFIG_QUOTA
5394
5395 /*
5396  * Helper functions so that transaction is started before we acquire dqio_sem
5397  * to keep correct lock ordering of transaction > dqio_sem
5398  */
5399 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5400 {
5401         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5402 }
5403
5404 static int ext4_write_dquot(struct dquot *dquot)
5405 {
5406         int ret, err;
5407         handle_t *handle;
5408         struct inode *inode;
5409
5410         inode = dquot_to_inode(dquot);
5411         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5412                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5413         if (IS_ERR(handle))
5414                 return PTR_ERR(handle);
5415         ret = dquot_commit(dquot);
5416         err = ext4_journal_stop(handle);
5417         if (!ret)
5418                 ret = err;
5419         return ret;
5420 }
5421
5422 static int ext4_acquire_dquot(struct dquot *dquot)
5423 {
5424         int ret, err;
5425         handle_t *handle;
5426
5427         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5428                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5429         if (IS_ERR(handle))
5430                 return PTR_ERR(handle);
5431         ret = dquot_acquire(dquot);
5432         err = ext4_journal_stop(handle);
5433         if (!ret)
5434                 ret = err;
5435         return ret;
5436 }
5437
5438 static int ext4_release_dquot(struct dquot *dquot)
5439 {
5440         int ret, err;
5441         handle_t *handle;
5442
5443         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5444                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5445         if (IS_ERR(handle)) {
5446                 /* Release dquot anyway to avoid endless cycle in dqput() */
5447                 dquot_release(dquot);
5448                 return PTR_ERR(handle);
5449         }
5450         ret = dquot_release(dquot);
5451         err = ext4_journal_stop(handle);
5452         if (!ret)
5453                 ret = err;
5454         return ret;
5455 }
5456
5457 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5458 {
5459         struct super_block *sb = dquot->dq_sb;
5460         struct ext4_sb_info *sbi = EXT4_SB(sb);
5461
5462         /* Are we journaling quotas? */
5463         if (ext4_has_feature_quota(sb) ||
5464             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5465                 dquot_mark_dquot_dirty(dquot);
5466                 return ext4_write_dquot(dquot);
5467         } else {
5468                 return dquot_mark_dquot_dirty(dquot);
5469         }
5470 }
5471
5472 static int ext4_write_info(struct super_block *sb, int type)
5473 {
5474         int ret, err;
5475         handle_t *handle;
5476
5477         /* Data block + inode block */
5478         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5479         if (IS_ERR(handle))
5480                 return PTR_ERR(handle);
5481         ret = dquot_commit_info(sb, type);
5482         err = ext4_journal_stop(handle);
5483         if (!ret)
5484                 ret = err;
5485         return ret;
5486 }
5487
5488 /*
5489  * Turn on quotas during mount time - we need to find
5490  * the quota file and such...
5491  */
5492 static int ext4_quota_on_mount(struct super_block *sb, int type)
5493 {
5494         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5495                                         EXT4_SB(sb)->s_jquota_fmt, type);
5496 }
5497
5498 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5499 {
5500         struct ext4_inode_info *ei = EXT4_I(inode);
5501
5502         /* The first argument of lockdep_set_subclass has to be
5503          * *exactly* the same as the argument to init_rwsem() --- in
5504          * this case, in init_once() --- or lockdep gets unhappy
5505          * because the name of the lock is set using the
5506          * stringification of the argument to init_rwsem().
5507          */
5508         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5509         lockdep_set_subclass(&ei->i_data_sem, subclass);
5510 }
5511
5512 /*
5513  * Standard function to be called on quota_on
5514  */
5515 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5516                          const struct path *path)
5517 {
5518         int err;
5519
5520         if (!test_opt(sb, QUOTA))
5521                 return -EINVAL;
5522
5523         /* Quotafile not on the same filesystem? */
5524         if (path->dentry->d_sb != sb)
5525                 return -EXDEV;
5526         /* Journaling quota? */
5527         if (EXT4_SB(sb)->s_qf_names[type]) {
5528                 /* Quotafile not in fs root? */
5529                 if (path->dentry->d_parent != sb->s_root)
5530                         ext4_msg(sb, KERN_WARNING,
5531                                 "Quota file not on filesystem root. "
5532                                 "Journaled quota will not work");
5533                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5534         } else {
5535                 /*
5536                  * Clear the flag just in case mount options changed since
5537                  * last time.
5538                  */
5539                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5540         }
5541
5542         /*
5543          * When we journal data on quota file, we have to flush journal to see
5544          * all updates to the file when we bypass pagecache...
5545          */
5546         if (EXT4_SB(sb)->s_journal &&
5547             ext4_should_journal_data(d_inode(path->dentry))) {
5548                 /*
5549                  * We don't need to lock updates but journal_flush() could
5550                  * otherwise be livelocked...
5551                  */
5552                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5553                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5554                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5555                 if (err)
5556                         return err;
5557         }
5558
5559         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5560         err = dquot_quota_on(sb, type, format_id, path);
5561         if (err) {
5562                 lockdep_set_quota_inode(path->dentry->d_inode,
5563                                              I_DATA_SEM_NORMAL);
5564         } else {
5565                 struct inode *inode = d_inode(path->dentry);
5566                 handle_t *handle;
5567
5568                 /*
5569                  * Set inode flags to prevent userspace from messing with quota
5570                  * files. If this fails, we return success anyway since quotas
5571                  * are already enabled and this is not a hard failure.
5572                  */
5573                 inode_lock(inode);
5574                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5575                 if (IS_ERR(handle))
5576                         goto unlock_inode;
5577                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5578                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5579                                 S_NOATIME | S_IMMUTABLE);
5580                 ext4_mark_inode_dirty(handle, inode);
5581                 ext4_journal_stop(handle);
5582         unlock_inode:
5583                 inode_unlock(inode);
5584         }
5585         return err;
5586 }
5587
5588 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5589                              unsigned int flags)
5590 {
5591         int err;
5592         struct inode *qf_inode;
5593         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5594                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5595                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5596                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5597         };
5598
5599         BUG_ON(!ext4_has_feature_quota(sb));
5600
5601         if (!qf_inums[type])
5602                 return -EPERM;
5603
5604         qf_inode = ext4_iget(sb, qf_inums[type]);
5605         if (IS_ERR(qf_inode)) {
5606                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5607                 return PTR_ERR(qf_inode);
5608         }
5609
5610         /* Don't account quota for quota files to avoid recursion */
5611         qf_inode->i_flags |= S_NOQUOTA;
5612         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5613         err = dquot_enable(qf_inode, type, format_id, flags);
5614         iput(qf_inode);
5615         if (err)
5616                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5617
5618         return err;
5619 }
5620
5621 /* Enable usage tracking for all quota types. */
5622 static int ext4_enable_quotas(struct super_block *sb)
5623 {
5624         int type, err = 0;
5625         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5626                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5627                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5628                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5629         };
5630         bool quota_mopt[EXT4_MAXQUOTAS] = {
5631                 test_opt(sb, USRQUOTA),
5632                 test_opt(sb, GRPQUOTA),
5633                 test_opt(sb, PRJQUOTA),
5634         };
5635
5636         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5637         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5638                 if (qf_inums[type]) {
5639                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5640                                 DQUOT_USAGE_ENABLED |
5641                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5642                         if (err) {
5643                                 for (type--; type >= 0; type--)
5644                                         dquot_quota_off(sb, type);
5645
5646                                 ext4_warning(sb,
5647                                         "Failed to enable quota tracking "
5648                                         "(type=%d, err=%d). Please run "
5649                                         "e2fsck to fix.", type, err);
5650                                 return err;
5651                         }
5652                 }
5653         }
5654         return 0;
5655 }
5656
5657 static int ext4_quota_off(struct super_block *sb, int type)
5658 {
5659         struct inode *inode = sb_dqopt(sb)->files[type];
5660         handle_t *handle;
5661         int err;
5662
5663         /* Force all delayed allocation blocks to be allocated.
5664          * Caller already holds s_umount sem */
5665         if (test_opt(sb, DELALLOC))
5666                 sync_filesystem(sb);
5667
5668         if (!inode || !igrab(inode))
5669                 goto out;
5670
5671         err = dquot_quota_off(sb, type);
5672         if (err || ext4_has_feature_quota(sb))
5673                 goto out_put;
5674
5675         inode_lock(inode);
5676         /*
5677          * Update modification times of quota files when userspace can
5678          * start looking at them. If we fail, we return success anyway since
5679          * this is not a hard failure and quotas are already disabled.
5680          */
5681         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5682         if (IS_ERR(handle))
5683                 goto out_unlock;
5684         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5685         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5686         inode->i_mtime = inode->i_ctime = current_time(inode);
5687         ext4_mark_inode_dirty(handle, inode);
5688         ext4_journal_stop(handle);
5689 out_unlock:
5690         inode_unlock(inode);
5691 out_put:
5692         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5693         iput(inode);
5694         return err;
5695 out:
5696         return dquot_quota_off(sb, type);
5697 }
5698
5699 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5700  * acquiring the locks... As quota files are never truncated and quota code
5701  * itself serializes the operations (and no one else should touch the files)
5702  * we don't have to be afraid of races */
5703 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5704                                size_t len, loff_t off)
5705 {
5706         struct inode *inode = sb_dqopt(sb)->files[type];
5707         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5708         int offset = off & (sb->s_blocksize - 1);
5709         int tocopy;
5710         size_t toread;
5711         struct buffer_head *bh;
5712         loff_t i_size = i_size_read(inode);
5713
5714         if (off > i_size)
5715                 return 0;
5716         if (off+len > i_size)
5717                 len = i_size-off;
5718         toread = len;
5719         while (toread > 0) {
5720                 tocopy = sb->s_blocksize - offset < toread ?
5721                                 sb->s_blocksize - offset : toread;
5722                 bh = ext4_bread(NULL, inode, blk, 0);
5723                 if (IS_ERR(bh))
5724                         return PTR_ERR(bh);
5725                 if (!bh)        /* A hole? */
5726                         memset(data, 0, tocopy);
5727                 else
5728                         memcpy(data, bh->b_data+offset, tocopy);
5729                 brelse(bh);
5730                 offset = 0;
5731                 toread -= tocopy;
5732                 data += tocopy;
5733                 blk++;
5734         }
5735         return len;
5736 }
5737
5738 /* Write to quotafile (we know the transaction is already started and has
5739  * enough credits) */
5740 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5741                                 const char *data, size_t len, loff_t off)
5742 {
5743         struct inode *inode = sb_dqopt(sb)->files[type];
5744         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5745         int err, offset = off & (sb->s_blocksize - 1);
5746         int retries = 0;
5747         struct buffer_head *bh;
5748         handle_t *handle = journal_current_handle();
5749
5750         if (EXT4_SB(sb)->s_journal && !handle) {
5751                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5752                         " cancelled because transaction is not started",
5753                         (unsigned long long)off, (unsigned long long)len);
5754                 return -EIO;
5755         }
5756         /*
5757          * Since we account only one data block in transaction credits,
5758          * then it is impossible to cross a block boundary.
5759          */
5760         if (sb->s_blocksize - offset < len) {
5761                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5762                         " cancelled because not block aligned",
5763                         (unsigned long long)off, (unsigned long long)len);
5764                 return -EIO;
5765         }
5766
5767         do {
5768                 bh = ext4_bread(handle, inode, blk,
5769                                 EXT4_GET_BLOCKS_CREATE |
5770                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5771         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5772                  ext4_should_retry_alloc(inode->i_sb, &retries));
5773         if (IS_ERR(bh))
5774                 return PTR_ERR(bh);
5775         if (!bh)
5776                 goto out;
5777         BUFFER_TRACE(bh, "get write access");
5778         err = ext4_journal_get_write_access(handle, bh);
5779         if (err) {
5780                 brelse(bh);
5781                 return err;
5782         }
5783         lock_buffer(bh);
5784         memcpy(bh->b_data+offset, data, len);
5785         flush_dcache_page(bh->b_page);
5786         unlock_buffer(bh);
5787         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5788         brelse(bh);
5789 out:
5790         if (inode->i_size < off + len) {
5791                 i_size_write(inode, off + len);
5792                 EXT4_I(inode)->i_disksize = inode->i_size;
5793                 ext4_mark_inode_dirty(handle, inode);
5794         }
5795         return len;
5796 }
5797
5798 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
5799 {
5800         const struct quota_format_ops   *ops;
5801
5802         if (!sb_has_quota_loaded(sb, qid->type))
5803                 return -ESRCH;
5804         ops = sb_dqopt(sb)->ops[qid->type];
5805         if (!ops || !ops->get_next_id)
5806                 return -ENOSYS;
5807         return dquot_get_next_id(sb, qid);
5808 }
5809 #endif
5810
5811 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5812                        const char *dev_name, void *data)
5813 {
5814         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5815 }
5816
5817 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5818 static inline void register_as_ext2(void)
5819 {
5820         int err = register_filesystem(&ext2_fs_type);
5821         if (err)
5822                 printk(KERN_WARNING
5823                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5824 }
5825
5826 static inline void unregister_as_ext2(void)
5827 {
5828         unregister_filesystem(&ext2_fs_type);
5829 }
5830
5831 static inline int ext2_feature_set_ok(struct super_block *sb)
5832 {
5833         if (ext4_has_unknown_ext2_incompat_features(sb))
5834                 return 0;
5835         if (sb_rdonly(sb))
5836                 return 1;
5837         if (ext4_has_unknown_ext2_ro_compat_features(sb))
5838                 return 0;
5839         return 1;
5840 }
5841 #else
5842 static inline void register_as_ext2(void) { }
5843 static inline void unregister_as_ext2(void) { }
5844 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5845 #endif
5846
5847 static inline void register_as_ext3(void)
5848 {
5849         int err = register_filesystem(&ext3_fs_type);
5850         if (err)
5851                 printk(KERN_WARNING
5852                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5853 }
5854
5855 static inline void unregister_as_ext3(void)
5856 {
5857         unregister_filesystem(&ext3_fs_type);
5858 }
5859
5860 static inline int ext3_feature_set_ok(struct super_block *sb)
5861 {
5862         if (ext4_has_unknown_ext3_incompat_features(sb))
5863                 return 0;
5864         if (!ext4_has_feature_journal(sb))
5865                 return 0;
5866         if (sb_rdonly(sb))
5867                 return 1;
5868         if (ext4_has_unknown_ext3_ro_compat_features(sb))
5869                 return 0;
5870         return 1;
5871 }
5872
5873 static struct file_system_type ext4_fs_type = {
5874         .owner          = THIS_MODULE,
5875         .name           = "ext4",
5876         .mount          = ext4_mount,
5877         .kill_sb        = kill_block_super,
5878         .fs_flags       = FS_REQUIRES_DEV,
5879 };
5880 MODULE_ALIAS_FS("ext4");
5881
5882 /* Shared across all ext4 file systems */
5883 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5884
5885 static int __init ext4_init_fs(void)
5886 {
5887         int i, err;
5888
5889         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
5890         ext4_li_info = NULL;
5891         mutex_init(&ext4_li_mtx);
5892
5893         /* Build-time check for flags consistency */
5894         ext4_check_flag_values();
5895
5896         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
5897                 init_waitqueue_head(&ext4__ioend_wq[i]);
5898
5899         err = ext4_init_es();
5900         if (err)
5901                 return err;
5902
5903         err = ext4_init_pageio();
5904         if (err)
5905                 goto out5;
5906
5907         err = ext4_init_system_zone();
5908         if (err)
5909                 goto out4;
5910
5911         err = ext4_init_sysfs();
5912         if (err)
5913                 goto out3;
5914
5915         err = ext4_init_mballoc();
5916         if (err)
5917                 goto out2;
5918         err = init_inodecache();
5919         if (err)
5920                 goto out1;
5921         register_as_ext3();
5922         register_as_ext2();
5923         err = register_filesystem(&ext4_fs_type);
5924         if (err)
5925                 goto out;
5926
5927         return 0;
5928 out:
5929         unregister_as_ext2();
5930         unregister_as_ext3();
5931         destroy_inodecache();
5932 out1:
5933         ext4_exit_mballoc();
5934 out2:
5935         ext4_exit_sysfs();
5936 out3:
5937         ext4_exit_system_zone();
5938 out4:
5939         ext4_exit_pageio();
5940 out5:
5941         ext4_exit_es();
5942
5943         return err;
5944 }
5945
5946 static void __exit ext4_exit_fs(void)
5947 {
5948         ext4_destroy_lazyinit_thread();
5949         unregister_as_ext2();
5950         unregister_as_ext3();
5951         unregister_filesystem(&ext4_fs_type);
5952         destroy_inodecache();
5953         ext4_exit_mballoc();
5954         ext4_exit_sysfs();
5955         ext4_exit_system_zone();
5956         ext4_exit_pageio();
5957         ext4_exit_es();
5958 }
5959
5960 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5961 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5962 MODULE_LICENSE("GPL");
5963 MODULE_SOFTDEP("pre: crc32c");
5964 module_init(ext4_init_fs)
5965 module_exit(ext4_exit_fs)