fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/backing-dev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/ctype.h>
  38 #include <linux/log2.h>
  39 #include <linux/crc16.h>
  40 #include <linux/dax.h>
  41 #include <linux/cleancache.h>
  42 #include <linux/uaccess.h>
  43
  44 #include <linux/kthread.h>
  45 #include <linux/freezer.h>
  46
  47 #include "ext4.h"
  48 #include "ext4_extents.h"       /* Needed for trace points definition */
  49 #include "ext4_jbd2.h"
  50 #include "xattr.h"
  51 #include "acl.h"
  52 #include "mballoc.h"
  53 #include "fsmap.h"
  54
  55 #define CREATE_TRACE_POINTS
  56 #include <trace/events/ext4.h>
  57
  58 static struct ext4_lazy_init *ext4_li_info;
  59 static struct mutex ext4_li_mtx;
  60 static struct ratelimit_state ext4_mount_msg_ratelimit;
  61
  62 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  63                              unsigned long journal_devnum);
  64 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  65 static int ext4_commit_super(struct super_block *sb, int sync);
  66 static void ext4_mark_recovery_complete(struct super_block *sb,
  67                                         struct ext4_super_block *es);
  68 static void ext4_clear_journal_err(struct super_block *sb,
  69                                    struct ext4_super_block *es);
  70 static int ext4_sync_fs(struct super_block *sb, int wait);
  71 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  72 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  73 static int ext4_unfreeze(struct super_block *sb);
  74 static int ext4_freeze(struct super_block *sb);
  75 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  76                        const char *dev_name, void *data);
  77 static inline int ext2_feature_set_ok(struct super_block *sb);
  78 static inline int ext3_feature_set_ok(struct super_block *sb);
  79 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  80 static void ext4_destroy_lazyinit_thread(void);
  81 static void ext4_unregister_li_request(struct super_block *sb);
  82 static void ext4_clear_request_list(void);
  83 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  84                                             unsigned int journal_inum);
  85
  86 /*
  87  * Lock ordering
  88  *
  89  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  90  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  91  *
  92  * page fault path:
  93  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  94  *   page lock -> i_data_sem (rw)
  95  *
  96  * buffered write path:
  97  * sb_start_write -> i_mutex -> mmap_sem
  98  * sb_start_write -> i_mutex -> transaction start -> page lock ->
  99  *   i_data_sem (rw)
 100  *
 101  * truncate:
 102  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 103  *   i_mmap_rwsem (w) -> page lock
 104  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 105  *   transaction start -> i_data_sem (rw)
 106  *
 107  * direct IO:
 108  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) -> mmap_sem
 109  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) ->
 110  *   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 (sb_rdonly(sb))
 409                 return;
 410
 411         if (!test_opt(sb, ERRORS_CONT)) {
 412                 journal_t *journal = EXT4_SB(sb)->s_journal;
 413
 414                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 415                 if (journal)
 416                         jbd2_journal_abort(journal, -EIO);
 417         }
 418         if (test_opt(sb, ERRORS_RO)) {
 419                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 420                 /*
 421                  * Make sure updated value of ->s_mount_flags will be visible
 422                  * before ->s_flags update
 423                  */
 424                 smp_wmb();
 425                 sb->s_flags |= MS_RDONLY;
 426         }
 427         if (test_opt(sb, ERRORS_PANIC)) {
 428                 if (EXT4_SB(sb)->s_journal &&
 429                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 430                         return;
 431                 panic("EXT4-fs (device %s): panic forced after error\n",
 432                         sb->s_id);
 433         }
 434 }
 435
 436 #define ext4_error_ratelimit(sb)                                        \
 437                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 438                              "EXT4-fs error")
 439
 440 void __ext4_error(struct super_block *sb, const char *function,
 441                   unsigned int line, const char *fmt, ...)
 442 {
 443         struct va_format vaf;
 444         va_list args;
 445
 446         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 447                 return;
 448
 449         if (ext4_error_ratelimit(sb)) {
 450                 va_start(args, fmt);
 451                 vaf.fmt = fmt;
 452                 vaf.va = &args;
 453                 printk(KERN_CRIT
 454                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 455                        sb->s_id, function, line, current->comm, &vaf);
 456                 va_end(args);
 457         }
 458         save_error_info(sb, function, line);
 459         ext4_handle_error(sb);
 460 }
 461
 462 void __ext4_error_inode(struct inode *inode, const char *function,
 463                         unsigned int line, ext4_fsblk_t block,
 464                         const char *fmt, ...)
 465 {
 466         va_list args;
 467         struct va_format vaf;
 468         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 469
 470         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 471                 return;
 472
 473         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 474         es->s_last_error_block = cpu_to_le64(block);
 475         if (ext4_error_ratelimit(inode->i_sb)) {
 476                 va_start(args, fmt);
 477                 vaf.fmt = fmt;
 478                 vaf.va = &args;
 479                 if (block)
 480                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 481                                "inode #%lu: block %llu: comm %s: %pV\n",
 482                                inode->i_sb->s_id, function, line, inode->i_ino,
 483                                block, current->comm, &vaf);
 484                 else
 485                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 486                                "inode #%lu: comm %s: %pV\n",
 487                                inode->i_sb->s_id, function, line, inode->i_ino,
 488                                current->comm, &vaf);
 489                 va_end(args);
 490         }
 491         save_error_info(inode->i_sb, function, line);
 492         ext4_handle_error(inode->i_sb);
 493 }
 494
 495 void __ext4_error_file(struct file *file, const char *function,
 496                        unsigned int line, ext4_fsblk_t block,
 497                        const char *fmt, ...)
 498 {
 499         va_list args;
 500         struct va_format vaf;
 501         struct ext4_super_block *es;
 502         struct inode *inode = file_inode(file);
 503         char pathname[80], *path;
 504
 505         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 506                 return;
 507
 508         es = EXT4_SB(inode->i_sb)->s_es;
 509         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 510         if (ext4_error_ratelimit(inode->i_sb)) {
 511                 path = file_path(file, pathname, sizeof(pathname));
 512                 if (IS_ERR(path))
 513                         path = "(unknown)";
 514                 va_start(args, fmt);
 515                 vaf.fmt = fmt;
 516                 vaf.va = &args;
 517                 if (block)
 518                         printk(KERN_CRIT
 519                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 520                                "block %llu: comm %s: path %s: %pV\n",
 521                                inode->i_sb->s_id, function, line, inode->i_ino,
 522                                block, current->comm, path, &vaf);
 523                 else
 524                         printk(KERN_CRIT
 525                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 526                                "comm %s: path %s: %pV\n",
 527                                inode->i_sb->s_id, function, line, inode->i_ino,
 528                                current->comm, path, &vaf);
 529                 va_end(args);
 530         }
 531         save_error_info(inode->i_sb, function, line);
 532         ext4_handle_error(inode->i_sb);
 533 }
 534
 535 const char *ext4_decode_error(struct super_block *sb, int errno,
 536                               char nbuf[16])
 537 {
 538         char *errstr = NULL;
 539
 540         switch (errno) {
 541         case -EFSCORRUPTED:
 542                 errstr = "Corrupt filesystem";
 543                 break;
 544         case -EFSBADCRC:
 545                 errstr = "Filesystem failed CRC";
 546                 break;
 547         case -EIO:
 548                 errstr = "IO failure";
 549                 break;
 550         case -ENOMEM:
 551                 errstr = "Out of memory";
 552                 break;
 553         case -EROFS:
 554                 if (!sb || (EXT4_SB(sb)->s_journal &&
 555                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 556                         errstr = "Journal has aborted";
 557                 else
 558                         errstr = "Readonly filesystem";
 559                 break;
 560         default:
 561                 /* If the caller passed in an extra buffer for unknown
 562                  * errors, textualise them now.  Else we just return
 563                  * NULL. */
 564                 if (nbuf) {
 565                         /* Check for truncated error codes... */
 566                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 567                                 errstr = nbuf;
 568                 }
 569                 break;
 570         }
 571
 572         return errstr;
 573 }
 574
 575 /* __ext4_std_error decodes expected errors from journaling functions
 576  * automatically and invokes the appropriate error response.  */
 577
 578 void __ext4_std_error(struct super_block *sb, const char *function,
 579                       unsigned int line, int errno)
 580 {
 581         char nbuf[16];
 582         const char *errstr;
 583
 584         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 585                 return;
 586
 587         /* Special case: if the error is EROFS, and we're not already
 588          * inside a transaction, then there's really no point in logging
 589          * an error. */
 590         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 591                 return;
 592
 593         if (ext4_error_ratelimit(sb)) {
 594                 errstr = ext4_decode_error(sb, errno, nbuf);
 595                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 596                        sb->s_id, function, line, errstr);
 597         }
 598
 599         save_error_info(sb, function, line);
 600         ext4_handle_error(sb);
 601 }
 602
 603 /*
 604  * ext4_abort is a much stronger failure handler than ext4_error.  The
 605  * abort function may be used to deal with unrecoverable failures such
 606  * as journal IO errors or ENOMEM at a critical moment in log management.
 607  *
 608  * We unconditionally force the filesystem into an ABORT|READONLY state,
 609  * unless the error response on the fs has been set to panic in which
 610  * case we take the easy way out and panic immediately.
 611  */
 612
 613 void __ext4_abort(struct super_block *sb, const char *function,
 614                 unsigned int line, const char *fmt, ...)
 615 {
 616         struct va_format vaf;
 617         va_list args;
 618
 619         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 620                 return;
 621
 622         save_error_info(sb, function, line);
 623         va_start(args, fmt);
 624         vaf.fmt = fmt;
 625         vaf.va = &args;
 626         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 627                sb->s_id, function, line, &vaf);
 628         va_end(args);
 629
 630         if (sb_rdonly(sb) == 0) {
 631                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 632                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 633                 /*
 634                  * Make sure updated value of ->s_mount_flags will be visible
 635                  * before ->s_flags update
 636                  */
 637                 smp_wmb();
 638                 sb->s_flags |= MS_RDONLY;
 639                 if (EXT4_SB(sb)->s_journal)
 640                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 641                 save_error_info(sb, function, line);
 642         }
 643         if (test_opt(sb, ERRORS_PANIC)) {
 644                 if (EXT4_SB(sb)->s_journal &&
 645                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 646                         return;
 647                 panic("EXT4-fs panic from previous error\n");
 648         }
 649 }
 650
 651 void __ext4_msg(struct super_block *sb,
 652                 const char *prefix, const char *fmt, ...)
 653 {
 654         struct va_format vaf;
 655         va_list args;
 656
 657         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 658                 return;
 659
 660         va_start(args, fmt);
 661         vaf.fmt = fmt;
 662         vaf.va = &args;
 663         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 664         va_end(args);
 665 }
 666
 667 #define ext4_warning_ratelimit(sb)                                      \
 668                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 669                              "EXT4-fs warning")
 670
 671 void __ext4_warning(struct super_block *sb, const char *function,
 672                     unsigned int line, const char *fmt, ...)
 673 {
 674         struct va_format vaf;
 675         va_list args;
 676
 677         if (!ext4_warning_ratelimit(sb))
 678                 return;
 679
 680         va_start(args, fmt);
 681         vaf.fmt = fmt;
 682         vaf.va = &args;
 683         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 684                sb->s_id, function, line, &vaf);
 685         va_end(args);
 686 }
 687
 688 void __ext4_warning_inode(const struct inode *inode, const char *function,
 689                           unsigned int line, const char *fmt, ...)
 690 {
 691         struct va_format vaf;
 692         va_list args;
 693
 694         if (!ext4_warning_ratelimit(inode->i_sb))
 695                 return;
 696
 697         va_start(args, fmt);
 698         vaf.fmt = fmt;
 699         vaf.va = &args;
 700         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 701                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 702                function, line, inode->i_ino, current->comm, &vaf);
 703         va_end(args);
 704 }
 705
 706 void __ext4_grp_locked_error(const char *function, unsigned int line,
 707                              struct super_block *sb, ext4_group_t grp,
 708                              unsigned long ino, ext4_fsblk_t block,
 709                              const char *fmt, ...)
 710 __releases(bitlock)
 711 __acquires(bitlock)
 712 {
 713         struct va_format vaf;
 714         va_list args;
 715         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 716
 717         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 718                 return;
 719
 720         es->s_last_error_ino = cpu_to_le32(ino);
 721         es->s_last_error_block = cpu_to_le64(block);
 722         __save_error_info(sb, function, line);
 723
 724         if (ext4_error_ratelimit(sb)) {
 725                 va_start(args, fmt);
 726                 vaf.fmt = fmt;
 727                 vaf.va = &args;
 728                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 729                        sb->s_id, function, line, grp);
 730                 if (ino)
 731                         printk(KERN_CONT "inode %lu: ", ino);
 732                 if (block)
 733                         printk(KERN_CONT "block %llu:",
 734                                (unsigned long long) block);
 735                 printk(KERN_CONT "%pV\n", &vaf);
 736                 va_end(args);
 737         }
 738
 739         if (test_opt(sb, ERRORS_CONT)) {
 740                 ext4_commit_super(sb, 0);
 741                 return;
 742         }
 743
 744         ext4_unlock_group(sb, grp);
 745         ext4_handle_error(sb);
 746         /*
 747          * We only get here in the ERRORS_RO case; relocking the group
 748          * may be dangerous, but nothing bad will happen since the
 749          * filesystem will have already been marked read/only and the
 750          * journal has been aborted.  We return 1 as a hint to callers
 751          * who might what to use the return value from
 752          * ext4_grp_locked_error() to distinguish between the
 753          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 754          * aggressively from the ext4 function in question, with a
 755          * more appropriate error code.
 756          */
 757         ext4_lock_group(sb, grp);
 758         return;
 759 }
 760
 761 void ext4_update_dynamic_rev(struct super_block *sb)
 762 {
 763         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 764
 765         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 766                 return;
 767
 768         ext4_warning(sb,
 769                      "updating to rev %d because of new feature flag, "
 770                      "running e2fsck is recommended",
 771                      EXT4_DYNAMIC_REV);
 772
 773         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 774         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 775         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 776         /* leave es->s_feature_*compat flags alone */
 777         /* es->s_uuid will be set by e2fsck if empty */
 778
 779         /*
 780          * The rest of the superblock fields should be zero, and if not it
 781          * means they are likely already in use, so leave them alone.  We
 782          * can leave it up to e2fsck to clean up any inconsistencies there.
 783          */
 784 }
 785
 786 /*
 787  * Open the external journal device
 788  */
 789 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 790 {
 791         struct block_device *bdev;
 792         char b[BDEVNAME_SIZE];
 793
 794         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 795         if (IS_ERR(bdev))
 796                 goto fail;
 797         return bdev;
 798
 799 fail:
 800         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 801                         __bdevname(dev, b), PTR_ERR(bdev));
 802         return NULL;
 803 }
 804
 805 /*
 806  * Release the journal device
 807  */
 808 static void ext4_blkdev_put(struct block_device *bdev)
 809 {
 810         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 811 }
 812
 813 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 814 {
 815         struct block_device *bdev;
 816         bdev = sbi->journal_bdev;
 817         if (bdev) {
 818                 ext4_blkdev_put(bdev);
 819                 sbi->journal_bdev = NULL;
 820         }
 821 }
 822
 823 static inline struct inode *orphan_list_entry(struct list_head *l)
 824 {
 825         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 826 }
 827
 828 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 829 {
 830         struct list_head *l;
 831
 832         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 833                  le32_to_cpu(sbi->s_es->s_last_orphan));
 834
 835         printk(KERN_ERR "sb_info orphan list:\n");
 836         list_for_each(l, &sbi->s_orphan) {
 837                 struct inode *inode = orphan_list_entry(l);
 838                 printk(KERN_ERR "  "
 839                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 840                        inode->i_sb->s_id, inode->i_ino, inode,
 841                        inode->i_mode, inode->i_nlink,
 842                        NEXT_ORPHAN(inode));
 843         }
 844 }
 845
 846 #ifdef CONFIG_QUOTA
 847 static int ext4_quota_off(struct super_block *sb, int type);
 848
 849 static inline void ext4_quota_off_umount(struct super_block *sb)
 850 {
 851         int type;
 852
 853         /* Use our quota_off function to clear inode flags etc. */
 854         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 855                 ext4_quota_off(sb, type);
 856 }
 857 #else
 858 static inline void ext4_quota_off_umount(struct super_block *sb)
 859 {
 860 }
 861 #endif
 862
 863 static void ext4_put_super(struct super_block *sb)
 864 {
 865         struct ext4_sb_info *sbi = EXT4_SB(sb);
 866         struct ext4_super_block *es = sbi->s_es;
 867         int aborted = 0;
 868         int i, err;
 869
 870         ext4_unregister_li_request(sb);
 871         ext4_quota_off_umount(sb);
 872
 873         flush_workqueue(sbi->rsv_conversion_wq);
 874         destroy_workqueue(sbi->rsv_conversion_wq);
 875
 876         if (sbi->s_journal) {
 877                 aborted = is_journal_aborted(sbi->s_journal);
 878                 err = jbd2_journal_destroy(sbi->s_journal);
 879                 sbi->s_journal = NULL;
 880                 if ((err < 0) && !aborted)
 881                         ext4_abort(sb, "Couldn't clean up the journal");
 882         }
 883
 884         ext4_unregister_sysfs(sb);
 885         ext4_es_unregister_shrinker(sbi);
 886         del_timer_sync(&sbi->s_err_report);
 887         ext4_release_system_zone(sb);
 888         ext4_mb_release(sb);
 889         ext4_ext_release(sb);
 890
 891         if (!sb_rdonly(sb) && !aborted) {
 892                 ext4_clear_feature_journal_needs_recovery(sb);
 893                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 894         }
 895         if (!sb_rdonly(sb))
 896                 ext4_commit_super(sb, 1);
 897
 898         for (i = 0; i < sbi->s_gdb_count; i++)
 899                 brelse(sbi->s_group_desc[i]);
 900         kvfree(sbi->s_group_desc);
 901         kvfree(sbi->s_flex_groups);
 902         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 903         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 904         percpu_counter_destroy(&sbi->s_dirs_counter);
 905         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 906         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
 907 #ifdef CONFIG_QUOTA
 908         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 909                 kfree(sbi->s_qf_names[i]);
 910 #endif
 911
 912         /* Debugging code just in case the in-memory inode orphan list
 913          * isn't empty.  The on-disk one can be non-empty if we've
 914          * detected an error and taken the fs readonly, but the
 915          * in-memory list had better be clean by this point. */
 916         if (!list_empty(&sbi->s_orphan))
 917                 dump_orphan_list(sb, sbi);
 918         J_ASSERT(list_empty(&sbi->s_orphan));
 919
 920         sync_blockdev(sb->s_bdev);
 921         invalidate_bdev(sb->s_bdev);
 922         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 923                 /*
 924                  * Invalidate the journal device's buffers.  We don't want them
 925                  * floating about in memory - the physical journal device may
 926                  * hotswapped, and it breaks the `ro-after' testing code.
 927                  */
 928                 sync_blockdev(sbi->journal_bdev);
 929                 invalidate_bdev(sbi->journal_bdev);
 930                 ext4_blkdev_remove(sbi);
 931         }
 932         if (sbi->s_ea_inode_cache) {
 933                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
 934                 sbi->s_ea_inode_cache = NULL;
 935         }
 936         if (sbi->s_ea_block_cache) {
 937                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
 938                 sbi->s_ea_block_cache = NULL;
 939         }
 940         if (sbi->s_mmp_tsk)
 941                 kthread_stop(sbi->s_mmp_tsk);
 942         brelse(sbi->s_sbh);
 943         sb->s_fs_info = NULL;
 944         /*
 945          * Now that we are completely done shutting down the
 946          * superblock, we need to actually destroy the kobject.
 947          */
 948         kobject_put(&sbi->s_kobj);
 949         wait_for_completion(&sbi->s_kobj_unregister);
 950         if (sbi->s_chksum_driver)
 951                 crypto_free_shash(sbi->s_chksum_driver);
 952         kfree(sbi->s_blockgroup_lock);
 953         fs_put_dax(sbi->s_daxdev);
 954         kfree(sbi);
 955 }
 956
 957 static struct kmem_cache *ext4_inode_cachep;
 958
 959 /*
 960  * Called inside transaction, so use GFP_NOFS
 961  */
 962 static struct inode *ext4_alloc_inode(struct super_block *sb)
 963 {
 964         struct ext4_inode_info *ei;
 965
 966         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 967         if (!ei)
 968                 return NULL;
 969
 970         ei->vfs_inode.i_version = 1;
 971         spin_lock_init(&ei->i_raw_lock);
 972         INIT_LIST_HEAD(&ei->i_prealloc_list);
 973         spin_lock_init(&ei->i_prealloc_lock);
 974         ext4_es_init_tree(&ei->i_es_tree);
 975         rwlock_init(&ei->i_es_lock);
 976         INIT_LIST_HEAD(&ei->i_es_list);
 977         ei->i_es_all_nr = 0;
 978         ei->i_es_shk_nr = 0;
 979         ei->i_es_shrink_lblk = 0;
 980         ei->i_reserved_data_blocks = 0;
 981         ei->i_da_metadata_calc_len = 0;
 982         ei->i_da_metadata_calc_last_lblock = 0;
 983         spin_lock_init(&(ei->i_block_reservation_lock));
 984 #ifdef CONFIG_QUOTA
 985         ei->i_reserved_quota = 0;
 986         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 987 #endif
 988         ei->jinode = NULL;
 989         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 990         spin_lock_init(&ei->i_completed_io_lock);
 991         ei->i_sync_tid = 0;
 992         ei->i_datasync_tid = 0;
 993         atomic_set(&ei->i_unwritten, 0);
 994         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 995         return &ei->vfs_inode;
 996 }
 997
 998 static int ext4_drop_inode(struct inode *inode)
 999 {
1000         int drop = generic_drop_inode(inode);
1001
1002         trace_ext4_drop_inode(inode, drop);
1003         return drop;
1004 }
1005
1006 static void ext4_i_callback(struct rcu_head *head)
1007 {
1008         struct inode *inode = container_of(head, struct inode, i_rcu);
1009         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1010 }
1011
1012 static void ext4_destroy_inode(struct inode *inode)
1013 {
1014         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1015                 ext4_msg(inode->i_sb, KERN_ERR,
1016                          "Inode %lu (%p): orphan list check failed!",
1017                          inode->i_ino, EXT4_I(inode));
1018                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1019                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1020                                 true);
1021                 dump_stack();
1022         }
1023         call_rcu(&inode->i_rcu, ext4_i_callback);
1024 }
1025
1026 static void init_once(void *foo)
1027 {
1028         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1029
1030         INIT_LIST_HEAD(&ei->i_orphan);
1031         init_rwsem(&ei->xattr_sem);
1032         init_rwsem(&ei->i_data_sem);
1033         init_rwsem(&ei->i_mmap_sem);
1034         inode_init_once(&ei->vfs_inode);
1035 }
1036
1037 static int __init init_inodecache(void)
1038 {
1039         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1040                                              sizeof(struct ext4_inode_info),
1041                                              0, (SLAB_RECLAIM_ACCOUNT|
1042                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
1043                                              init_once);
1044         if (ext4_inode_cachep == NULL)
1045                 return -ENOMEM;
1046         return 0;
1047 }
1048
1049 static void destroy_inodecache(void)
1050 {
1051         /*
1052          * Make sure all delayed rcu free inodes are flushed before we
1053          * destroy cache.
1054          */
1055         rcu_barrier();
1056         kmem_cache_destroy(ext4_inode_cachep);
1057 }
1058
1059 void ext4_clear_inode(struct inode *inode)
1060 {
1061         invalidate_inode_buffers(inode);
1062         clear_inode(inode);
1063         dquot_drop(inode);
1064         ext4_discard_preallocations(inode);
1065         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1066         if (EXT4_I(inode)->jinode) {
1067                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1068                                                EXT4_I(inode)->jinode);
1069                 jbd2_free_inode(EXT4_I(inode)->jinode);
1070                 EXT4_I(inode)->jinode = NULL;
1071         }
1072 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1073         fscrypt_put_encryption_info(inode, NULL);
1074 #endif
1075 }
1076
1077 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1078                                         u64 ino, u32 generation)
1079 {
1080         struct inode *inode;
1081
1082         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1083                 return ERR_PTR(-ESTALE);
1084         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1085                 return ERR_PTR(-ESTALE);
1086
1087         /* iget isn't really right if the inode is currently unallocated!!
1088          *
1089          * ext4_read_inode will return a bad_inode if the inode had been
1090          * deleted, so we should be safe.
1091          *
1092          * Currently we don't know the generation for parent directory, so
1093          * a generation of 0 means "accept any"
1094          */
1095         inode = ext4_iget_normal(sb, ino);
1096         if (IS_ERR(inode))
1097                 return ERR_CAST(inode);
1098         if (generation && inode->i_generation != generation) {
1099                 iput(inode);
1100                 return ERR_PTR(-ESTALE);
1101         }
1102
1103         return inode;
1104 }
1105
1106 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1107                                         int fh_len, int fh_type)
1108 {
1109         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1110                                     ext4_nfs_get_inode);
1111 }
1112
1113 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1114                                         int fh_len, int fh_type)
1115 {
1116         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1117                                     ext4_nfs_get_inode);
1118 }
1119
1120 /*
1121  * Try to release metadata pages (indirect blocks, directories) which are
1122  * mapped via the block device.  Since these pages could have journal heads
1123  * which would prevent try_to_free_buffers() from freeing them, we must use
1124  * jbd2 layer's try_to_free_buffers() function to release them.
1125  */
1126 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1127                                  gfp_t wait)
1128 {
1129         journal_t *journal = EXT4_SB(sb)->s_journal;
1130
1131         WARN_ON(PageChecked(page));
1132         if (!page_has_buffers(page))
1133                 return 0;
1134         if (journal)
1135                 return jbd2_journal_try_to_free_buffers(journal, page,
1136                                                 wait & ~__GFP_DIRECT_RECLAIM);
1137         return try_to_free_buffers(page);
1138 }
1139
1140 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1141 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1142 {
1143         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1144                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1145 }
1146
1147 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1148                                                         void *fs_data)
1149 {
1150         handle_t *handle = fs_data;
1151         int res, res2, credits, retries = 0;
1152
1153         /*
1154          * Encrypting the root directory is not allowed because e2fsck expects
1155          * lost+found to exist and be unencrypted, and encrypting the root
1156          * directory would imply encrypting the lost+found directory as well as
1157          * the filename "lost+found" itself.
1158          */
1159         if (inode->i_ino == EXT4_ROOT_INO)
1160                 return -EPERM;
1161
1162         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1163                 return -EINVAL;
1164
1165         res = ext4_convert_inline_data(inode);
1166         if (res)
1167                 return res;
1168
1169         /*
1170          * If a journal handle was specified, then the encryption context is
1171          * being set on a new inode via inheritance and is part of a larger
1172          * transaction to create the inode.  Otherwise the encryption context is
1173          * being set on an existing inode in its own transaction.  Only in the
1174          * latter case should the "retry on ENOSPC" logic be used.
1175          */
1176
1177         if (handle) {
1178                 res = ext4_xattr_set_handle(handle, inode,
1179                                             EXT4_XATTR_INDEX_ENCRYPTION,
1180                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1181                                             ctx, len, 0);
1182                 if (!res) {
1183                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1184                         ext4_clear_inode_state(inode,
1185                                         EXT4_STATE_MAY_INLINE_DATA);
1186                         /*
1187                          * Update inode->i_flags - e.g. S_DAX may get disabled
1188                          */
1189                         ext4_set_inode_flags(inode);
1190                 }
1191                 return res;
1192         }
1193
1194         res = dquot_initialize(inode);
1195         if (res)
1196                 return res;
1197 retry:
1198         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1199                                      &credits);
1200         if (res)
1201                 return res;
1202
1203         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1204         if (IS_ERR(handle))
1205                 return PTR_ERR(handle);
1206
1207         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1208                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1209                                     ctx, len, 0);
1210         if (!res) {
1211                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1212                 /* Update inode->i_flags - e.g. S_DAX may get disabled */
1213                 ext4_set_inode_flags(inode);
1214                 res = ext4_mark_inode_dirty(handle, inode);
1215                 if (res)
1216                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1217         }
1218         res2 = ext4_journal_stop(handle);
1219
1220         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1221                 goto retry;
1222         if (!res)
1223                 res = res2;
1224         return res;
1225 }
1226
1227 static bool ext4_dummy_context(struct inode *inode)
1228 {
1229         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1230 }
1231
1232 static unsigned ext4_max_namelen(struct inode *inode)
1233 {
1234         return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
1235                 EXT4_NAME_LEN;
1236 }
1237
1238 static const struct fscrypt_operations ext4_cryptops = {
1239         .key_prefix             = "ext4:",
1240         .get_context            = ext4_get_context,
1241         .set_context            = ext4_set_context,
1242         .dummy_context          = ext4_dummy_context,
1243         .is_encrypted           = ext4_encrypted_inode,
1244         .empty_dir              = ext4_empty_dir,
1245         .max_namelen            = ext4_max_namelen,
1246 };
1247 #else
1248 static const struct fscrypt_operations ext4_cryptops = {
1249         .is_encrypted           = ext4_encrypted_inode,
1250 };
1251 #endif
1252
1253 #ifdef CONFIG_QUOTA
1254 static const char * const quotatypes[] = INITQFNAMES;
1255 #define QTYPE2NAME(t) (quotatypes[t])
1256
1257 static int ext4_write_dquot(struct dquot *dquot);
1258 static int ext4_acquire_dquot(struct dquot *dquot);
1259 static int ext4_release_dquot(struct dquot *dquot);
1260 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1261 static int ext4_write_info(struct super_block *sb, int type);
1262 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1263                          const struct path *path);
1264 static int ext4_quota_on_mount(struct super_block *sb, int type);
1265 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1266                                size_t len, loff_t off);
1267 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1268                                 const char *data, size_t len, loff_t off);
1269 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1270                              unsigned int flags);
1271 static int ext4_enable_quotas(struct super_block *sb);
1272 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1273
1274 static struct dquot **ext4_get_dquots(struct inode *inode)
1275 {
1276         return EXT4_I(inode)->i_dquot;
1277 }
1278
1279 static const struct dquot_operations ext4_quota_operations = {
1280         .get_reserved_space     = ext4_get_reserved_space,
1281         .write_dquot            = ext4_write_dquot,
1282         .acquire_dquot          = ext4_acquire_dquot,
1283         .release_dquot          = ext4_release_dquot,
1284         .mark_dirty             = ext4_mark_dquot_dirty,
1285         .write_info             = ext4_write_info,
1286         .alloc_dquot            = dquot_alloc,
1287         .destroy_dquot          = dquot_destroy,
1288         .get_projid             = ext4_get_projid,
1289         .get_inode_usage        = ext4_get_inode_usage,
1290         .get_next_id            = ext4_get_next_id,
1291 };
1292
1293 static const struct quotactl_ops ext4_qctl_operations = {
1294         .quota_on       = ext4_quota_on,
1295         .quota_off      = ext4_quota_off,
1296         .quota_sync     = dquot_quota_sync,
1297         .get_state      = dquot_get_state,
1298         .set_info       = dquot_set_dqinfo,
1299         .get_dqblk      = dquot_get_dqblk,
1300         .set_dqblk      = dquot_set_dqblk,
1301         .get_nextdqblk  = dquot_get_next_dqblk,
1302 };
1303 #endif
1304
1305 static const struct super_operations ext4_sops = {
1306         .alloc_inode    = ext4_alloc_inode,
1307         .destroy_inode  = ext4_destroy_inode,
1308         .write_inode    = ext4_write_inode,
1309         .dirty_inode    = ext4_dirty_inode,
1310         .drop_inode     = ext4_drop_inode,
1311         .evict_inode    = ext4_evict_inode,
1312         .put_super      = ext4_put_super,
1313         .sync_fs        = ext4_sync_fs,
1314         .freeze_fs      = ext4_freeze,
1315         .unfreeze_fs    = ext4_unfreeze,
1316         .statfs         = ext4_statfs,
1317         .remount_fs     = ext4_remount,
1318         .show_options   = ext4_show_options,
1319 #ifdef CONFIG_QUOTA
1320         .quota_read     = ext4_quota_read,
1321         .quota_write    = ext4_quota_write,
1322         .get_dquots     = ext4_get_dquots,
1323 #endif
1324         .bdev_try_to_free_page = bdev_try_to_free_page,
1325 };
1326
1327 static const struct export_operations ext4_export_ops = {
1328         .fh_to_dentry = ext4_fh_to_dentry,
1329         .fh_to_parent = ext4_fh_to_parent,
1330         .get_parent = ext4_get_parent,
1331 };
1332
1333 enum {
1334         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1335         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1336         Opt_nouid32, Opt_debug, Opt_removed,
1337         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1338         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1339         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1340         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1341         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1342         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1343         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1344         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1345         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1346         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1347         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1348         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1349         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1350         Opt_inode_readahead_blks, Opt_journal_ioprio,
1351         Opt_dioread_nolock, Opt_dioread_lock,
1352         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1353         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1354 };
1355
1356 static const match_table_t tokens = {
1357         {Opt_bsd_df, "bsddf"},
1358         {Opt_minix_df, "minixdf"},
1359         {Opt_grpid, "grpid"},
1360         {Opt_grpid, "bsdgroups"},
1361         {Opt_nogrpid, "nogrpid"},
1362         {Opt_nogrpid, "sysvgroups"},
1363         {Opt_resgid, "resgid=%u"},
1364         {Opt_resuid, "resuid=%u"},
1365         {Opt_sb, "sb=%u"},
1366         {Opt_err_cont, "errors=continue"},
1367         {Opt_err_panic, "errors=panic"},
1368         {Opt_err_ro, "errors=remount-ro"},
1369         {Opt_nouid32, "nouid32"},
1370         {Opt_debug, "debug"},
1371         {Opt_removed, "oldalloc"},
1372         {Opt_removed, "orlov"},
1373         {Opt_user_xattr, "user_xattr"},
1374         {Opt_nouser_xattr, "nouser_xattr"},
1375         {Opt_acl, "acl"},
1376         {Opt_noacl, "noacl"},
1377         {Opt_noload, "norecovery"},
1378         {Opt_noload, "noload"},
1379         {Opt_removed, "nobh"},
1380         {Opt_removed, "bh"},
1381         {Opt_commit, "commit=%u"},
1382         {Opt_min_batch_time, "min_batch_time=%u"},
1383         {Opt_max_batch_time, "max_batch_time=%u"},
1384         {Opt_journal_dev, "journal_dev=%u"},
1385         {Opt_journal_path, "journal_path=%s"},
1386         {Opt_journal_checksum, "journal_checksum"},
1387         {Opt_nojournal_checksum, "nojournal_checksum"},
1388         {Opt_journal_async_commit, "journal_async_commit"},
1389         {Opt_abort, "abort"},
1390         {Opt_data_journal, "data=journal"},
1391         {Opt_data_ordered, "data=ordered"},
1392         {Opt_data_writeback, "data=writeback"},
1393         {Opt_data_err_abort, "data_err=abort"},
1394         {Opt_data_err_ignore, "data_err=ignore"},
1395         {Opt_offusrjquota, "usrjquota="},
1396         {Opt_usrjquota, "usrjquota=%s"},
1397         {Opt_offgrpjquota, "grpjquota="},
1398         {Opt_grpjquota, "grpjquota=%s"},
1399         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1400         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1401         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1402         {Opt_grpquota, "grpquota"},
1403         {Opt_noquota, "noquota"},
1404         {Opt_quota, "quota"},
1405         {Opt_usrquota, "usrquota"},
1406         {Opt_prjquota, "prjquota"},
1407         {Opt_barrier, "barrier=%u"},
1408         {Opt_barrier, "barrier"},
1409         {Opt_nobarrier, "nobarrier"},
1410         {Opt_i_version, "i_version"},
1411         {Opt_dax, "dax"},
1412         {Opt_stripe, "stripe=%u"},
1413         {Opt_delalloc, "delalloc"},
1414         {Opt_lazytime, "lazytime"},
1415         {Opt_nolazytime, "nolazytime"},
1416         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1417         {Opt_nodelalloc, "nodelalloc"},
1418         {Opt_removed, "mblk_io_submit"},
1419         {Opt_removed, "nomblk_io_submit"},
1420         {Opt_block_validity, "block_validity"},
1421         {Opt_noblock_validity, "noblock_validity"},
1422         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1423         {Opt_journal_ioprio, "journal_ioprio=%u"},
1424         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1425         {Opt_auto_da_alloc, "auto_da_alloc"},
1426         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1427         {Opt_dioread_nolock, "dioread_nolock"},
1428         {Opt_dioread_lock, "dioread_lock"},
1429         {Opt_discard, "discard"},
1430         {Opt_nodiscard, "nodiscard"},
1431         {Opt_init_itable, "init_itable=%u"},
1432         {Opt_init_itable, "init_itable"},
1433         {Opt_noinit_itable, "noinit_itable"},
1434         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1435         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1436         {Opt_nombcache, "nombcache"},
1437         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1438         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1439         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1440         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1441         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1442         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1443         {Opt_err, NULL},
1444 };
1445
1446 static ext4_fsblk_t get_sb_block(void **data)
1447 {
1448         ext4_fsblk_t    sb_block;
1449         char            *options = (char *) *data;
1450
1451         if (!options || strncmp(options, "sb=", 3) != 0)
1452                 return 1;       /* Default location */
1453
1454         options += 3;
1455         /* TODO: use simple_strtoll with >32bit ext4 */
1456         sb_block = simple_strtoul(options, &options, 0);
1457         if (*options && *options != ',') {
1458                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1459                        (char *) *data);
1460                 return 1;
1461         }
1462         if (*options == ',')
1463                 options++;
1464         *data = (void *) options;
1465
1466         return sb_block;
1467 }
1468
1469 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1470 static const char deprecated_msg[] =
1471         "Mount option \"%s\" will be removed by %s\n"
1472         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1473
1474 #ifdef CONFIG_QUOTA
1475 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1476 {
1477         struct ext4_sb_info *sbi = EXT4_SB(sb);
1478         char *qname;
1479         int ret = -1;
1480
1481         if (sb_any_quota_loaded(sb) &&
1482                 !sbi->s_qf_names[qtype]) {
1483                 ext4_msg(sb, KERN_ERR,
1484                         "Cannot change journaled "
1485                         "quota options when quota turned on");
1486                 return -1;
1487         }
1488         if (ext4_has_feature_quota(sb)) {
1489                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1490                          "ignored when QUOTA feature is enabled");
1491                 return 1;
1492         }
1493         qname = match_strdup(args);
1494         if (!qname) {
1495                 ext4_msg(sb, KERN_ERR,
1496                         "Not enough memory for storing quotafile name");
1497                 return -1;
1498         }
1499         if (sbi->s_qf_names[qtype]) {
1500                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1501                         ret = 1;
1502                 else
1503                         ext4_msg(sb, KERN_ERR,
1504                                  "%s quota file already specified",
1505                                  QTYPE2NAME(qtype));
1506                 goto errout;
1507         }
1508         if (strchr(qname, '/')) {
1509                 ext4_msg(sb, KERN_ERR,
1510                         "quotafile must be on filesystem root");
1511                 goto errout;
1512         }
1513         sbi->s_qf_names[qtype] = qname;
1514         set_opt(sb, QUOTA);
1515         return 1;
1516 errout:
1517         kfree(qname);
1518         return ret;
1519 }
1520
1521 static int clear_qf_name(struct super_block *sb, int qtype)
1522 {
1523
1524         struct ext4_sb_info *sbi = EXT4_SB(sb);
1525
1526         if (sb_any_quota_loaded(sb) &&
1527                 sbi->s_qf_names[qtype]) {
1528                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1529                         " when quota turned on");
1530                 return -1;
1531         }
1532         kfree(sbi->s_qf_names[qtype]);
1533         sbi->s_qf_names[qtype] = NULL;
1534         return 1;
1535 }
1536 #endif
1537
1538 #define MOPT_SET        0x0001
1539 #define MOPT_CLEAR      0x0002
1540 #define MOPT_NOSUPPORT  0x0004
1541 #define MOPT_EXPLICIT   0x0008
1542 #define MOPT_CLEAR_ERR  0x0010
1543 #define MOPT_GTE0       0x0020
1544 #ifdef CONFIG_QUOTA
1545 #define MOPT_Q          0
1546 #define MOPT_QFMT       0x0040
1547 #else
1548 #define MOPT_Q          MOPT_NOSUPPORT
1549 #define MOPT_QFMT       MOPT_NOSUPPORT
1550 #endif
1551 #define MOPT_DATAJ      0x0080
1552 #define MOPT_NO_EXT2    0x0100
1553 #define MOPT_NO_EXT3    0x0200
1554 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1555 #define MOPT_STRING     0x0400
1556
1557 static const struct mount_opts {
1558         int     token;
1559         int     mount_opt;
1560         int     flags;
1561 } ext4_mount_opts[] = {
1562         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1563         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1564         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1565         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1566         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1567         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1568         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1569          MOPT_EXT4_ONLY | MOPT_SET},
1570         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1571          MOPT_EXT4_ONLY | MOPT_CLEAR},
1572         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1573         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1574         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1575          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1576         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1577          MOPT_EXT4_ONLY | MOPT_CLEAR},
1578         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1579          MOPT_EXT4_ONLY | MOPT_CLEAR},
1580         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1581          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1582         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1583                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1584          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1585         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1586         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1587         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1588         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1589         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1590          MOPT_NO_EXT2},
1591         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1592          MOPT_NO_EXT2},
1593         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1594         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1595         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1596         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1597         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1598         {Opt_commit, 0, MOPT_GTE0},
1599         {Opt_max_batch_time, 0, MOPT_GTE0},
1600         {Opt_min_batch_time, 0, MOPT_GTE0},
1601         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1602         {Opt_init_itable, 0, MOPT_GTE0},
1603         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1604         {Opt_stripe, 0, MOPT_GTE0},
1605         {Opt_resuid, 0, MOPT_GTE0},
1606         {Opt_resgid, 0, MOPT_GTE0},
1607         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1608         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1609         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1610         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1611         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1612         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1613          MOPT_NO_EXT2 | MOPT_DATAJ},
1614         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1615         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1616 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1617         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1618         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1619 #else
1620         {Opt_acl, 0, MOPT_NOSUPPORT},
1621         {Opt_noacl, 0, MOPT_NOSUPPORT},
1622 #endif
1623         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1624         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1625         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1626         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1627         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1628                                                         MOPT_SET | MOPT_Q},
1629         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1630                                                         MOPT_SET | MOPT_Q},
1631         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1632                                                         MOPT_SET | MOPT_Q},
1633         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1634                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1635                                                         MOPT_CLEAR | MOPT_Q},
1636         {Opt_usrjquota, 0, MOPT_Q},
1637         {Opt_grpjquota, 0, MOPT_Q},
1638         {Opt_offusrjquota, 0, MOPT_Q},
1639         {Opt_offgrpjquota, 0, MOPT_Q},
1640         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1641         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1642         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1643         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1644         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1645         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1646         {Opt_err, 0, 0}
1647 };
1648
1649 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1650                             substring_t *args, unsigned long *journal_devnum,
1651                             unsigned int *journal_ioprio, int is_remount)
1652 {
1653         struct ext4_sb_info *sbi = EXT4_SB(sb);
1654         const struct mount_opts *m;
1655         kuid_t uid;
1656         kgid_t gid;
1657         int arg = 0;
1658
1659 #ifdef CONFIG_QUOTA
1660         if (token == Opt_usrjquota)
1661                 return set_qf_name(sb, USRQUOTA, &args[0]);
1662         else if (token == Opt_grpjquota)
1663                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1664         else if (token == Opt_offusrjquota)
1665                 return clear_qf_name(sb, USRQUOTA);
1666         else if (token == Opt_offgrpjquota)
1667                 return clear_qf_name(sb, GRPQUOTA);
1668 #endif
1669         switch (token) {
1670         case Opt_noacl:
1671         case Opt_nouser_xattr:
1672                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1673                 break;
1674         case Opt_sb:
1675                 return 1;       /* handled by get_sb_block() */
1676         case Opt_removed:
1677                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1678                 return 1;
1679         case Opt_abort:
1680                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1681                 return 1;
1682         case Opt_i_version:
1683                 sb->s_flags |= MS_I_VERSION;
1684                 return 1;
1685         case Opt_lazytime:
1686                 sb->s_flags |= MS_LAZYTIME;
1687                 return 1;
1688         case Opt_nolazytime:
1689                 sb->s_flags &= ~MS_LAZYTIME;
1690                 return 1;
1691         }
1692
1693         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1694                 if (token == m->token)
1695                         break;
1696
1697         if (m->token == Opt_err) {
1698                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1699                          "or missing value", opt);
1700                 return -1;
1701         }
1702
1703         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1704                 ext4_msg(sb, KERN_ERR,
1705                          "Mount option \"%s\" incompatible with ext2", opt);
1706                 return -1;
1707         }
1708         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1709                 ext4_msg(sb, KERN_ERR,
1710                          "Mount option \"%s\" incompatible with ext3", opt);
1711                 return -1;
1712         }
1713
1714         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1715                 return -1;
1716         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1717                 return -1;
1718         if (m->flags & MOPT_EXPLICIT) {
1719                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1720                         set_opt2(sb, EXPLICIT_DELALLOC);
1721                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1722                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1723                 } else
1724                         return -1;
1725         }
1726         if (m->flags & MOPT_CLEAR_ERR)
1727                 clear_opt(sb, ERRORS_MASK);
1728         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1729                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1730                          "options when quota turned on");
1731                 return -1;
1732         }
1733
1734         if (m->flags & MOPT_NOSUPPORT) {
1735                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1736         } else if (token == Opt_commit) {
1737                 if (arg == 0)
1738                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1739                 sbi->s_commit_interval = HZ * arg;
1740         } else if (token == Opt_debug_want_extra_isize) {
1741                 sbi->s_want_extra_isize = arg;
1742         } else if (token == Opt_max_batch_time) {
1743                 sbi->s_max_batch_time = arg;
1744         } else if (token == Opt_min_batch_time) {
1745                 sbi->s_min_batch_time = arg;
1746         } else if (token == Opt_inode_readahead_blks) {
1747                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1748                         ext4_msg(sb, KERN_ERR,
1749                                  "EXT4-fs: inode_readahead_blks must be "
1750                                  "0 or a power of 2 smaller than 2^31");
1751                         return -1;
1752                 }
1753                 sbi->s_inode_readahead_blks = arg;
1754         } else if (token == Opt_init_itable) {
1755                 set_opt(sb, INIT_INODE_TABLE);
1756                 if (!args->from)
1757                         arg = EXT4_DEF_LI_WAIT_MULT;
1758                 sbi->s_li_wait_mult = arg;
1759         } else if (token == Opt_max_dir_size_kb) {
1760                 sbi->s_max_dir_size_kb = arg;
1761         } else if (token == Opt_stripe) {
1762                 sbi->s_stripe = arg;
1763         } else if (token == Opt_resuid) {
1764                 uid = make_kuid(current_user_ns(), arg);
1765                 if (!uid_valid(uid)) {
1766                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1767                         return -1;
1768                 }
1769                 sbi->s_resuid = uid;
1770         } else if (token == Opt_resgid) {
1771                 gid = make_kgid(current_user_ns(), arg);
1772                 if (!gid_valid(gid)) {
1773                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1774                         return -1;
1775                 }
1776                 sbi->s_resgid = gid;
1777         } else if (token == Opt_journal_dev) {
1778                 if (is_remount) {
1779                         ext4_msg(sb, KERN_ERR,
1780                                  "Cannot specify journal on remount");
1781                         return -1;
1782                 }
1783                 *journal_devnum = arg;
1784         } else if (token == Opt_journal_path) {
1785                 char *journal_path;
1786                 struct inode *journal_inode;
1787                 struct path path;
1788                 int error;
1789
1790                 if (is_remount) {
1791                         ext4_msg(sb, KERN_ERR,
1792                                  "Cannot specify journal on remount");
1793                         return -1;
1794                 }
1795                 journal_path = match_strdup(&args[0]);
1796                 if (!journal_path) {
1797                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1798                                 "journal device string");
1799                         return -1;
1800                 }
1801
1802                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1803                 if (error) {
1804                         ext4_msg(sb, KERN_ERR, "error: could not find "
1805                                 "journal device path: error %d", error);
1806                         kfree(journal_path);
1807                         return -1;
1808                 }
1809
1810                 journal_inode = d_inode(path.dentry);
1811                 if (!S_ISBLK(journal_inode->i_mode)) {
1812                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1813                                 "is not a block device", journal_path);
1814                         path_put(&path);
1815                         kfree(journal_path);
1816                         return -1;
1817                 }
1818
1819                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1820                 path_put(&path);
1821                 kfree(journal_path);
1822         } else if (token == Opt_journal_ioprio) {
1823                 if (arg > 7) {
1824                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1825                                  " (must be 0-7)");
1826                         return -1;
1827                 }
1828                 *journal_ioprio =
1829                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1830         } else if (token == Opt_test_dummy_encryption) {
1831 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1832                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1833                 ext4_msg(sb, KERN_WARNING,
1834                          "Test dummy encryption mode enabled");
1835 #else
1836                 ext4_msg(sb, KERN_WARNING,
1837                          "Test dummy encryption mount option ignored");
1838 #endif
1839         } else if (m->flags & MOPT_DATAJ) {
1840                 if (is_remount) {
1841                         if (!sbi->s_journal)
1842                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1843                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1844                                 ext4_msg(sb, KERN_ERR,
1845                                          "Cannot change data mode on remount");
1846                                 return -1;
1847                         }
1848                 } else {
1849                         clear_opt(sb, DATA_FLAGS);
1850                         sbi->s_mount_opt |= m->mount_opt;
1851                 }
1852 #ifdef CONFIG_QUOTA
1853         } else if (m->flags & MOPT_QFMT) {
1854                 if (sb_any_quota_loaded(sb) &&
1855                     sbi->s_jquota_fmt != m->mount_opt) {
1856                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1857                                  "quota options when quota turned on");
1858                         return -1;
1859                 }
1860                 if (ext4_has_feature_quota(sb)) {
1861                         ext4_msg(sb, KERN_INFO,
1862                                  "Quota format mount options ignored "
1863                                  "when QUOTA feature is enabled");
1864                         return 1;
1865                 }
1866                 sbi->s_jquota_fmt = m->mount_opt;
1867 #endif
1868         } else if (token == Opt_dax) {
1869 #ifdef CONFIG_FS_DAX
1870                 ext4_msg(sb, KERN_WARNING,
1871                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1872                         sbi->s_mount_opt |= m->mount_opt;
1873 #else
1874                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1875                 return -1;
1876 #endif
1877         } else if (token == Opt_data_err_abort) {
1878                 sbi->s_mount_opt |= m->mount_opt;
1879         } else if (token == Opt_data_err_ignore) {
1880                 sbi->s_mount_opt &= ~m->mount_opt;
1881         } else {
1882                 if (!args->from)
1883                         arg = 1;
1884                 if (m->flags & MOPT_CLEAR)
1885                         arg = !arg;
1886                 else if (unlikely(!(m->flags & MOPT_SET))) {
1887                         ext4_msg(sb, KERN_WARNING,
1888                                  "buggy handling of option %s", opt);
1889                         WARN_ON(1);
1890                         return -1;
1891                 }
1892                 if (arg != 0)
1893                         sbi->s_mount_opt |= m->mount_opt;
1894                 else
1895                         sbi->s_mount_opt &= ~m->mount_opt;
1896         }
1897         return 1;
1898 }
1899
1900 static int parse_options(char *options, struct super_block *sb,
1901                          unsigned long *journal_devnum,
1902                          unsigned int *journal_ioprio,
1903                          int is_remount)
1904 {
1905         struct ext4_sb_info *sbi = EXT4_SB(sb);
1906         char *p;
1907         substring_t args[MAX_OPT_ARGS];
1908         int token;
1909
1910         if (!options)
1911                 return 1;
1912
1913         while ((p = strsep(&options, ",")) != NULL) {
1914                 if (!*p)
1915                         continue;
1916                 /*
1917                  * Initialize args struct so we know whether arg was
1918                  * found; some options take optional arguments.
1919                  */
1920                 args[0].to = args[0].from = NULL;
1921                 token = match_token(p, tokens, args);
1922                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1923                                      journal_ioprio, is_remount) < 0)
1924                         return 0;
1925         }
1926 #ifdef CONFIG_QUOTA
1927         /*
1928          * We do the test below only for project quotas. 'usrquota' and
1929          * 'grpquota' mount options are allowed even without quota feature
1930          * to support legacy quotas in quota files.
1931          */
1932         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
1933                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
1934                          "Cannot enable project quota enforcement.");
1935                 return 0;
1936         }
1937         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1938                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1939                         clear_opt(sb, USRQUOTA);
1940
1941                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1942                         clear_opt(sb, GRPQUOTA);
1943
1944                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1945                         ext4_msg(sb, KERN_ERR, "old and new quota "
1946                                         "format mixing");
1947                         return 0;
1948                 }
1949
1950                 if (!sbi->s_jquota_fmt) {
1951                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1952                                         "not specified");
1953                         return 0;
1954                 }
1955         }
1956 #endif
1957         if (test_opt(sb, DIOREAD_NOLOCK)) {
1958                 int blocksize =
1959                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1960
1961                 if (blocksize < PAGE_SIZE) {
1962                         ext4_msg(sb, KERN_ERR, "can't mount with "
1963                                  "dioread_nolock if block size != PAGE_SIZE");
1964                         return 0;
1965                 }
1966         }
1967         return 1;
1968 }
1969
1970 static inline void ext4_show_quota_options(struct seq_file *seq,
1971                                            struct super_block *sb)
1972 {
1973 #if defined(CONFIG_QUOTA)
1974         struct ext4_sb_info *sbi = EXT4_SB(sb);
1975
1976         if (sbi->s_jquota_fmt) {
1977                 char *fmtname = "";
1978
1979                 switch (sbi->s_jquota_fmt) {
1980                 case QFMT_VFS_OLD:
1981                         fmtname = "vfsold";
1982                         break;
1983                 case QFMT_VFS_V0:
1984                         fmtname = "vfsv0";
1985                         break;
1986                 case QFMT_VFS_V1:
1987                         fmtname = "vfsv1";
1988                         break;
1989                 }
1990                 seq_printf(seq, ",jqfmt=%s", fmtname);
1991         }
1992
1993         if (sbi->s_qf_names[USRQUOTA])
1994                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
1995
1996         if (sbi->s_qf_names[GRPQUOTA])
1997                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
1998 #endif
1999 }
2000
2001 static const char *token2str(int token)
2002 {
2003         const struct match_token *t;
2004
2005         for (t = tokens; t->token != Opt_err; t++)
2006                 if (t->token == token && !strchr(t->pattern, '='))
2007                         break;
2008         return t->pattern;
2009 }
2010
2011 /*
2012  * Show an option if
2013  *  - it's set to a non-default value OR
2014  *  - if the per-sb default is different from the global default
2015  */
2016 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2017                               int nodefs)
2018 {
2019         struct ext4_sb_info *sbi = EXT4_SB(sb);
2020         struct ext4_super_block *es = sbi->s_es;
2021         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
2022         const struct mount_opts *m;
2023         char sep = nodefs ? '\n' : ',';
2024
2025 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2026 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2027
2028         if (sbi->s_sb_block != 1)
2029                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2030
2031         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2032                 int want_set = m->flags & MOPT_SET;
2033                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2034                     (m->flags & MOPT_CLEAR_ERR))
2035                         continue;
2036                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2037                         continue; /* skip if same as the default */
2038                 if ((want_set &&
2039                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2040                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2041                         continue; /* select Opt_noFoo vs Opt_Foo */
2042                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2043         }
2044
2045         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2046             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2047                 SEQ_OPTS_PRINT("resuid=%u",
2048                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2049         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2050             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2051                 SEQ_OPTS_PRINT("resgid=%u",
2052                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2053         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2054         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2055                 SEQ_OPTS_PUTS("errors=remount-ro");
2056         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2057                 SEQ_OPTS_PUTS("errors=continue");
2058         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2059                 SEQ_OPTS_PUTS("errors=panic");
2060         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2061                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2062         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2063                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2064         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2065                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2066         if (sb->s_flags & MS_I_VERSION)
2067                 SEQ_OPTS_PUTS("i_version");
2068         if (nodefs || sbi->s_stripe)
2069                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2070         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
2071                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2072                         SEQ_OPTS_PUTS("data=journal");
2073                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2074                         SEQ_OPTS_PUTS("data=ordered");
2075                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2076                         SEQ_OPTS_PUTS("data=writeback");
2077         }
2078         if (nodefs ||
2079             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2080                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2081                                sbi->s_inode_readahead_blks);
2082
2083         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
2084                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2085                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2086         if (nodefs || sbi->s_max_dir_size_kb)
2087                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2088         if (test_opt(sb, DATA_ERR_ABORT))
2089                 SEQ_OPTS_PUTS("data_err=abort");
2090
2091         ext4_show_quota_options(seq, sb);
2092         return 0;
2093 }
2094
2095 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2096 {
2097         return _ext4_show_options(seq, root->d_sb, 0);
2098 }
2099
2100 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2101 {
2102         struct super_block *sb = seq->private;
2103         int rc;
2104
2105         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2106         rc = _ext4_show_options(seq, sb, 1);
2107         seq_puts(seq, "\n");
2108         return rc;
2109 }
2110
2111 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2112                             int read_only)
2113 {
2114         struct ext4_sb_info *sbi = EXT4_SB(sb);
2115         int res = 0;
2116
2117         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2118                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2119                          "forcing read-only mode");
2120                 res = MS_RDONLY;
2121         }
2122         if (read_only)
2123                 goto done;
2124         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2125                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2126                          "running e2fsck is recommended");
2127         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2128                 ext4_msg(sb, KERN_WARNING,
2129                          "warning: mounting fs with errors, "
2130                          "running e2fsck is recommended");
2131         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2132                  le16_to_cpu(es->s_mnt_count) >=
2133                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2134                 ext4_msg(sb, KERN_WARNING,
2135                          "warning: maximal mount count reached, "
2136                          "running e2fsck is recommended");
2137         else if (le32_to_cpu(es->s_checkinterval) &&
2138                 (le32_to_cpu(es->s_lastcheck) +
2139                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
2140                 ext4_msg(sb, KERN_WARNING,
2141                          "warning: checktime reached, "
2142                          "running e2fsck is recommended");
2143         if (!sbi->s_journal)
2144                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2145         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2146                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2147         le16_add_cpu(&es->s_mnt_count, 1);
2148         es->s_mtime = cpu_to_le32(get_seconds());
2149         ext4_update_dynamic_rev(sb);
2150         if (sbi->s_journal)
2151                 ext4_set_feature_journal_needs_recovery(sb);
2152
2153         ext4_commit_super(sb, 1);
2154 done:
2155         if (test_opt(sb, DEBUG))
2156                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2157                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2158                         sb->s_blocksize,
2159                         sbi->s_groups_count,
2160                         EXT4_BLOCKS_PER_GROUP(sb),
2161                         EXT4_INODES_PER_GROUP(sb),
2162                         sbi->s_mount_opt, sbi->s_mount_opt2);
2163
2164         cleancache_init_fs(sb);
2165         return res;
2166 }
2167
2168 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2169 {
2170         struct ext4_sb_info *sbi = EXT4_SB(sb);
2171         struct flex_groups *new_groups;
2172         int size;
2173
2174         if (!sbi->s_log_groups_per_flex)
2175                 return 0;
2176
2177         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2178         if (size <= sbi->s_flex_groups_allocated)
2179                 return 0;
2180
2181         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2182         new_groups = kvzalloc(size, GFP_KERNEL);
2183         if (!new_groups) {
2184                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2185                          size / (int) sizeof(struct flex_groups));
2186                 return -ENOMEM;
2187         }
2188
2189         if (sbi->s_flex_groups) {
2190                 memcpy(new_groups, sbi->s_flex_groups,
2191                        (sbi->s_flex_groups_allocated *
2192                         sizeof(struct flex_groups)));
2193                 kvfree(sbi->s_flex_groups);
2194         }
2195         sbi->s_flex_groups = new_groups;
2196         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2197         return 0;
2198 }
2199
2200 static int ext4_fill_flex_info(struct super_block *sb)
2201 {
2202         struct ext4_sb_info *sbi = EXT4_SB(sb);
2203         struct ext4_group_desc *gdp = NULL;
2204         ext4_group_t flex_group;
2205         int i, err;
2206
2207         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2208         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2209                 sbi->s_log_groups_per_flex = 0;
2210                 return 1;
2211         }
2212
2213         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2214         if (err)
2215                 goto failed;
2216
2217         for (i = 0; i < sbi->s_groups_count; i++) {
2218                 gdp = ext4_get_group_desc(sb, i, NULL);
2219
2220                 flex_group = ext4_flex_group(sbi, i);
2221                 atomic_add(ext4_free_inodes_count(sb, gdp),
2222                            &sbi->s_flex_groups[flex_group].free_inodes);
2223                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2224                              &sbi->s_flex_groups[flex_group].free_clusters);
2225                 atomic_add(ext4_used_dirs_count(sb, gdp),
2226                            &sbi->s_flex_groups[flex_group].used_dirs);
2227         }
2228
2229         return 1;
2230 failed:
2231         return 0;
2232 }
2233
2234 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2235                                    struct ext4_group_desc *gdp)
2236 {
2237         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2238         __u16 crc = 0;
2239         __le32 le_group = cpu_to_le32(block_group);
2240         struct ext4_sb_info *sbi = EXT4_SB(sb);
2241
2242         if (ext4_has_metadata_csum(sbi->s_sb)) {
2243                 /* Use new metadata_csum algorithm */
2244                 __u32 csum32;
2245                 __u16 dummy_csum = 0;
2246
2247                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2248                                      sizeof(le_group));
2249                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2250                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2251                                      sizeof(dummy_csum));
2252                 offset += sizeof(dummy_csum);
2253                 if (offset < sbi->s_desc_size)
2254                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2255                                              sbi->s_desc_size - offset);
2256
2257                 crc = csum32 & 0xFFFF;
2258                 goto out;
2259         }
2260
2261         /* old crc16 code */
2262         if (!ext4_has_feature_gdt_csum(sb))
2263                 return 0;
2264
2265         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2266         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2267         crc = crc16(crc, (__u8 *)gdp, offset);
2268         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2269         /* for checksum of struct ext4_group_desc do the rest...*/
2270         if (ext4_has_feature_64bit(sb) &&
2271             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2272                 crc = crc16(crc, (__u8 *)gdp + offset,
2273                             le16_to_cpu(sbi->s_es->s_desc_size) -
2274                                 offset);
2275
2276 out:
2277         return cpu_to_le16(crc);
2278 }
2279
2280 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2281                                 struct ext4_group_desc *gdp)
2282 {
2283         if (ext4_has_group_desc_csum(sb) &&
2284             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2285                 return 0;
2286
2287         return 1;
2288 }
2289
2290 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2291                               struct ext4_group_desc *gdp)
2292 {
2293         if (!ext4_has_group_desc_csum(sb))
2294                 return;
2295         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2296 }
2297
2298 /* Called at mount-time, super-block is locked */
2299 static int ext4_check_descriptors(struct super_block *sb,
2300                                   ext4_fsblk_t sb_block,
2301                                   ext4_group_t *first_not_zeroed)
2302 {
2303         struct ext4_sb_info *sbi = EXT4_SB(sb);
2304         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2305         ext4_fsblk_t last_block;
2306         ext4_fsblk_t block_bitmap;
2307         ext4_fsblk_t inode_bitmap;
2308         ext4_fsblk_t inode_table;
2309         int flexbg_flag = 0;
2310         ext4_group_t i, grp = sbi->s_groups_count;
2311
2312         if (ext4_has_feature_flex_bg(sb))
2313                 flexbg_flag = 1;
2314
2315         ext4_debug("Checking group descriptors");
2316
2317         for (i = 0; i < sbi->s_groups_count; i++) {
2318                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2319
2320                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2321                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2322                 else
2323                         last_block = first_block +
2324                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2325
2326                 if ((grp == sbi->s_groups_count) &&
2327                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2328                         grp = i;
2329
2330                 block_bitmap = ext4_block_bitmap(sb, gdp);
2331                 if (block_bitmap == sb_block) {
2332                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2333                                  "Block bitmap for group %u overlaps "
2334                                  "superblock", i);
2335                 }
2336                 if (block_bitmap < first_block || block_bitmap > last_block) {
2337                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2338                                "Block bitmap for group %u not in group "
2339                                "(block %llu)!", i, block_bitmap);
2340                         return 0;
2341                 }
2342                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2343                 if (inode_bitmap == sb_block) {
2344                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2345                                  "Inode bitmap for group %u overlaps "
2346                                  "superblock", i);
2347                 }
2348                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2349                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2350                                "Inode bitmap for group %u not in group "
2351                                "(block %llu)!", i, inode_bitmap);
2352                         return 0;
2353                 }
2354                 inode_table = ext4_inode_table(sb, gdp);
2355                 if (inode_table == sb_block) {
2356                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2357                                  "Inode table for group %u overlaps "
2358                                  "superblock", i);
2359                 }
2360                 if (inode_table < first_block ||
2361                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2362                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2363                                "Inode table for group %u not in group "
2364                                "(block %llu)!", i, inode_table);
2365                         return 0;
2366                 }
2367                 ext4_lock_group(sb, i);
2368                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2369                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2370                                  "Checksum for group %u failed (%u!=%u)",
2371                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2372                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2373                         if (!sb_rdonly(sb)) {
2374                                 ext4_unlock_group(sb, i);
2375                                 return 0;
2376                         }
2377                 }
2378                 ext4_unlock_group(sb, i);
2379                 if (!flexbg_flag)
2380                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2381         }
2382         if (NULL != first_not_zeroed)
2383                 *first_not_zeroed = grp;
2384         return 1;
2385 }
2386
2387 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2388  * the superblock) which were deleted from all directories, but held open by
2389  * a process at the time of a crash.  We walk the list and try to delete these
2390  * inodes at recovery time (only with a read-write filesystem).
2391  *
2392  * In order to keep the orphan inode chain consistent during traversal (in
2393  * case of crash during recovery), we link each inode into the superblock
2394  * orphan list_head and handle it the same way as an inode deletion during
2395  * normal operation (which journals the operations for us).
2396  *
2397  * We only do an iget() and an iput() on each inode, which is very safe if we
2398  * accidentally point at an in-use or already deleted inode.  The worst that
2399  * can happen in this case is that we get a "bit already cleared" message from
2400  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2401  * e2fsck was run on this filesystem, and it must have already done the orphan
2402  * inode cleanup for us, so we can safely abort without any further action.
2403  */
2404 static void ext4_orphan_cleanup(struct super_block *sb,
2405                                 struct ext4_super_block *es)
2406 {
2407         unsigned int s_flags = sb->s_flags;
2408         int ret, nr_orphans = 0, nr_truncates = 0;
2409 #ifdef CONFIG_QUOTA
2410         int quota_update = 0;
2411         int i;
2412 #endif
2413         if (!es->s_last_orphan) {
2414                 jbd_debug(4, "no orphan inodes to clean up\n");
2415                 return;
2416         }
2417
2418         if (bdev_read_only(sb->s_bdev)) {
2419                 ext4_msg(sb, KERN_ERR, "write access "
2420                         "unavailable, skipping orphan cleanup");
2421                 return;
2422         }
2423
2424         /* Check if feature set would not allow a r/w mount */
2425         if (!ext4_feature_set_ok(sb, 0)) {
2426                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2427                          "unknown ROCOMPAT features");
2428                 return;
2429         }
2430
2431         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2432                 /* don't clear list on RO mount w/ errors */
2433                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2434                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2435                                   "clearing orphan list.\n");
2436                         es->s_last_orphan = 0;
2437                 }
2438                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2439                 return;
2440         }
2441
2442         if (s_flags & MS_RDONLY) {
2443                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2444                 sb->s_flags &= ~MS_RDONLY;
2445         }
2446 #ifdef CONFIG_QUOTA
2447         /* Needed for iput() to work correctly and not trash data */
2448         sb->s_flags |= MS_ACTIVE;
2449
2450         /*
2451          * Turn on quotas which were not enabled for read-only mounts if
2452          * filesystem has quota feature, so that they are updated correctly.
2453          */
2454         if (ext4_has_feature_quota(sb) && (s_flags & MS_RDONLY)) {
2455                 int ret = ext4_enable_quotas(sb);
2456
2457                 if (!ret)
2458                         quota_update = 1;
2459                 else
2460                         ext4_msg(sb, KERN_ERR,
2461                                 "Cannot turn on quotas: error %d", ret);
2462         }
2463
2464         /* Turn on journaled quotas used for old sytle */
2465         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2466                 if (EXT4_SB(sb)->s_qf_names[i]) {
2467                         int ret = ext4_quota_on_mount(sb, i);
2468
2469                         if (!ret)
2470                                 quota_update = 1;
2471                         else
2472                                 ext4_msg(sb, KERN_ERR,
2473                                         "Cannot turn on journaled "
2474                                         "quota: type %d: error %d", i, ret);
2475                 }
2476         }
2477 #endif
2478
2479         while (es->s_last_orphan) {
2480                 struct inode *inode;
2481
2482                 /*
2483                  * We may have encountered an error during cleanup; if
2484                  * so, skip the rest.
2485                  */
2486                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2487                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2488                         es->s_last_orphan = 0;
2489                         break;
2490                 }
2491
2492                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2493                 if (IS_ERR(inode)) {
2494                         es->s_last_orphan = 0;
2495                         break;
2496                 }
2497
2498                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2499                 dquot_initialize(inode);
2500                 if (inode->i_nlink) {
2501                         if (test_opt(sb, DEBUG))
2502                                 ext4_msg(sb, KERN_DEBUG,
2503                                         "%s: truncating inode %lu to %lld bytes",
2504                                         __func__, inode->i_ino, inode->i_size);
2505                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2506                                   inode->i_ino, inode->i_size);
2507                         inode_lock(inode);
2508                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2509                         ret = ext4_truncate(inode);
2510                         if (ret)
2511                                 ext4_std_error(inode->i_sb, ret);
2512                         inode_unlock(inode);
2513                         nr_truncates++;
2514                 } else {
2515                         if (test_opt(sb, DEBUG))
2516                                 ext4_msg(sb, KERN_DEBUG,
2517                                         "%s: deleting unreferenced inode %lu",
2518                                         __func__, inode->i_ino);
2519                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2520                                   inode->i_ino);
2521                         nr_orphans++;
2522                 }
2523                 iput(inode);  /* The delete magic happens here! */
2524         }
2525
2526 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2527
2528         if (nr_orphans)
2529                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2530                        PLURAL(nr_orphans));
2531         if (nr_truncates)
2532                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2533                        PLURAL(nr_truncates));
2534 #ifdef CONFIG_QUOTA
2535         /* Turn off quotas if they were enabled for orphan cleanup */
2536         if (quota_update) {
2537                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2538                         if (sb_dqopt(sb)->files[i])
2539                                 dquot_quota_off(sb, i);
2540                 }
2541         }
2542 #endif
2543         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2544 }
2545
2546 /*
2547  * Maximal extent format file size.
2548  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2549  * extent format containers, within a sector_t, and within i_blocks
2550  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2551  * so that won't be a limiting factor.
2552  *
2553  * However there is other limiting factor. We do store extents in the form
2554  * of starting block and length, hence the resulting length of the extent
2555  * covering maximum file size must fit into on-disk format containers as
2556  * well. Given that length is always by 1 unit bigger than max unit (because
2557  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2558  *
2559  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2560  */
2561 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2562 {
2563         loff_t res;
2564         loff_t upper_limit = MAX_LFS_FILESIZE;
2565
2566         /* small i_blocks in vfs inode? */
2567         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2568                 /*
2569                  * CONFIG_LBDAF is not enabled implies the inode
2570                  * i_block represent total blocks in 512 bytes
2571                  * 32 == size of vfs inode i_blocks * 8
2572                  */
2573                 upper_limit = (1LL << 32) - 1;
2574
2575                 /* total blocks in file system block size */
2576                 upper_limit >>= (blkbits - 9);
2577                 upper_limit <<= blkbits;
2578         }
2579
2580         /*
2581          * 32-bit extent-start container, ee_block. We lower the maxbytes
2582          * by one fs block, so ee_len can cover the extent of maximum file
2583          * size
2584          */
2585         res = (1LL << 32) - 1;
2586         res <<= blkbits;
2587
2588         /* Sanity check against vm- & vfs- imposed limits */
2589         if (res > upper_limit)
2590                 res = upper_limit;
2591
2592         return res;
2593 }
2594
2595 /*
2596  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2597  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2598  * We need to be 1 filesystem block less than the 2^48 sector limit.
2599  */
2600 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2601 {
2602         loff_t res = EXT4_NDIR_BLOCKS;
2603         int meta_blocks;
2604         loff_t upper_limit;
2605         /* This is calculated to be the largest file size for a dense, block
2606          * mapped file such that the file's total number of 512-byte sectors,
2607          * including data and all indirect blocks, does not exceed (2^48 - 1).
2608          *
2609          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2610          * number of 512-byte sectors of the file.
2611          */
2612
2613         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2614                 /*
2615                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2616                  * the inode i_block field represents total file blocks in
2617                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2618                  */
2619                 upper_limit = (1LL << 32) - 1;
2620
2621                 /* total blocks in file system block size */
2622                 upper_limit >>= (bits - 9);
2623
2624         } else {
2625                 /*
2626                  * We use 48 bit ext4_inode i_blocks
2627                  * With EXT4_HUGE_FILE_FL set the i_blocks
2628                  * represent total number of blocks in
2629                  * file system block size
2630                  */
2631                 upper_limit = (1LL << 48) - 1;
2632
2633         }
2634
2635         /* indirect blocks */
2636         meta_blocks = 1;
2637         /* double indirect blocks */
2638         meta_blocks += 1 + (1LL << (bits-2));
2639         /* tripple indirect blocks */
2640         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2641
2642         upper_limit -= meta_blocks;
2643         upper_limit <<= bits;
2644
2645         res += 1LL << (bits-2);
2646         res += 1LL << (2*(bits-2));
2647         res += 1LL << (3*(bits-2));
2648         res <<= bits;
2649         if (res > upper_limit)
2650                 res = upper_limit;
2651
2652         if (res > MAX_LFS_FILESIZE)
2653                 res = MAX_LFS_FILESIZE;
2654
2655         return res;
2656 }
2657
2658 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2659                                    ext4_fsblk_t logical_sb_block, int nr)
2660 {
2661         struct ext4_sb_info *sbi = EXT4_SB(sb);
2662         ext4_group_t bg, first_meta_bg;
2663         int has_super = 0;
2664
2665         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2666
2667         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2668                 return logical_sb_block + nr + 1;
2669         bg = sbi->s_desc_per_block * nr;
2670         if (ext4_bg_has_super(sb, bg))
2671                 has_super = 1;
2672
2673         /*
2674          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2675          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2676          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2677          * compensate.
2678          */
2679         if (sb->s_blocksize == 1024 && nr == 0 &&
2680             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2681                 has_super++;
2682
2683         return (has_super + ext4_group_first_block_no(sb, bg));
2684 }
2685
2686 /**
2687  * ext4_get_stripe_size: Get the stripe size.
2688  * @sbi: In memory super block info
2689  *
2690  * If we have specified it via mount option, then
2691  * use the mount option value. If the value specified at mount time is
2692  * greater than the blocks per group use the super block value.
2693  * If the super block value is greater than blocks per group return 0.
2694  * Allocator needs it be less than blocks per group.
2695  *
2696  */
2697 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2698 {
2699         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2700         unsigned long stripe_width =
2701                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2702         int ret;
2703
2704         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2705                 ret = sbi->s_stripe;
2706         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2707                 ret = stripe_width;
2708         else if (stride && stride <= sbi->s_blocks_per_group)
2709                 ret = stride;
2710         else
2711                 ret = 0;
2712
2713         /*
2714          * If the stripe width is 1, this makes no sense and
2715          * we set it to 0 to turn off stripe handling code.
2716          */
2717         if (ret <= 1)
2718                 ret = 0;
2719
2720         return ret;
2721 }
2722
2723 /*
2724  * Check whether this filesystem can be mounted based on
2725  * the features present and the RDONLY/RDWR mount requested.
2726  * Returns 1 if this filesystem can be mounted as requested,
2727  * 0 if it cannot be.
2728  */
2729 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2730 {
2731         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2732                 ext4_msg(sb, KERN_ERR,
2733                         "Couldn't mount because of "
2734                         "unsupported optional features (%x)",
2735                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2736                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2737                 return 0;
2738         }
2739
2740         if (readonly)
2741                 return 1;
2742
2743         if (ext4_has_feature_readonly(sb)) {
2744                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2745                 sb->s_flags |= MS_RDONLY;
2746                 return 1;
2747         }
2748
2749         /* Check that feature set is OK for a read-write mount */
2750         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2751                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2752                          "unsupported optional features (%x)",
2753                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2754                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2755                 return 0;
2756         }
2757         /*
2758          * Large file size enabled file system can only be mounted
2759          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2760          */
2761         if (ext4_has_feature_huge_file(sb)) {
2762                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2763                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2764                                  "cannot be mounted RDWR without "
2765                                  "CONFIG_LBDAF");
2766                         return 0;
2767                 }
2768         }
2769         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2770                 ext4_msg(sb, KERN_ERR,
2771                          "Can't support bigalloc feature without "
2772                          "extents feature\n");
2773                 return 0;
2774         }
2775
2776 #ifndef CONFIG_QUOTA
2777         if (ext4_has_feature_quota(sb) && !readonly) {
2778                 ext4_msg(sb, KERN_ERR,
2779                          "Filesystem with quota feature cannot be mounted RDWR "
2780                          "without CONFIG_QUOTA");
2781                 return 0;
2782         }
2783         if (ext4_has_feature_project(sb) && !readonly) {
2784                 ext4_msg(sb, KERN_ERR,
2785                          "Filesystem with project quota feature cannot be mounted RDWR "
2786                          "without CONFIG_QUOTA");
2787                 return 0;
2788         }
2789 #endif  /* CONFIG_QUOTA */
2790         return 1;
2791 }
2792
2793 /*
2794  * This function is called once a day if we have errors logged
2795  * on the file system
2796  */
2797 static void print_daily_error_info(unsigned long arg)
2798 {
2799         struct super_block *sb = (struct super_block *) arg;
2800         struct ext4_sb_info *sbi;
2801         struct ext4_super_block *es;
2802
2803         sbi = EXT4_SB(sb);
2804         es = sbi->s_es;
2805
2806         if (es->s_error_count)
2807                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2808                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2809                          le32_to_cpu(es->s_error_count));
2810         if (es->s_first_error_time) {
2811                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2812                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2813                        (int) sizeof(es->s_first_error_func),
2814                        es->s_first_error_func,
2815                        le32_to_cpu(es->s_first_error_line));
2816                 if (es->s_first_error_ino)
2817                         printk(KERN_CONT ": inode %u",
2818                                le32_to_cpu(es->s_first_error_ino));
2819                 if (es->s_first_error_block)
2820                         printk(KERN_CONT ": block %llu", (unsigned long long)
2821                                le64_to_cpu(es->s_first_error_block));
2822                 printk(KERN_CONT "\n");
2823         }
2824         if (es->s_last_error_time) {
2825                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2826                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2827                        (int) sizeof(es->s_last_error_func),
2828                        es->s_last_error_func,
2829                        le32_to_cpu(es->s_last_error_line));
2830                 if (es->s_last_error_ino)
2831                         printk(KERN_CONT ": inode %u",
2832                                le32_to_cpu(es->s_last_error_ino));
2833                 if (es->s_last_error_block)
2834                         printk(KERN_CONT ": block %llu", (unsigned long long)
2835                                le64_to_cpu(es->s_last_error_block));
2836                 printk(KERN_CONT "\n");
2837         }
2838         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2839 }
2840
2841 /* Find next suitable group and run ext4_init_inode_table */
2842 static int ext4_run_li_request(struct ext4_li_request *elr)
2843 {
2844         struct ext4_group_desc *gdp = NULL;
2845         ext4_group_t group, ngroups;
2846         struct super_block *sb;
2847         unsigned long timeout = 0;
2848         int ret = 0;
2849
2850         sb = elr->lr_super;
2851         ngroups = EXT4_SB(sb)->s_groups_count;
2852
2853         for (group = elr->lr_next_group; group < ngroups; group++) {
2854                 gdp = ext4_get_group_desc(sb, group, NULL);
2855                 if (!gdp) {
2856                         ret = 1;
2857                         break;
2858                 }
2859
2860                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2861                         break;
2862         }
2863
2864         if (group >= ngroups)
2865                 ret = 1;
2866
2867         if (!ret) {
2868                 timeout = jiffies;
2869                 ret = ext4_init_inode_table(sb, group,
2870                                             elr->lr_timeout ? 0 : 1);
2871                 if (elr->lr_timeout == 0) {
2872                         timeout = (jiffies - timeout) *
2873                                   elr->lr_sbi->s_li_wait_mult;
2874                         elr->lr_timeout = timeout;
2875                 }
2876                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2877                 elr->lr_next_group = group + 1;
2878         }
2879         return ret;
2880 }
2881
2882 /*
2883  * Remove lr_request from the list_request and free the
2884  * request structure. Should be called with li_list_mtx held
2885  */
2886 static void ext4_remove_li_request(struct ext4_li_request *elr)
2887 {
2888         struct ext4_sb_info *sbi;
2889
2890         if (!elr)
2891                 return;
2892
2893         sbi = elr->lr_sbi;
2894
2895         list_del(&elr->lr_request);
2896         sbi->s_li_request = NULL;
2897         kfree(elr);
2898 }
2899
2900 static void ext4_unregister_li_request(struct super_block *sb)
2901 {
2902         mutex_lock(&ext4_li_mtx);
2903         if (!ext4_li_info) {
2904                 mutex_unlock(&ext4_li_mtx);
2905                 return;
2906         }
2907
2908         mutex_lock(&ext4_li_info->li_list_mtx);
2909         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2910         mutex_unlock(&ext4_li_info->li_list_mtx);
2911         mutex_unlock(&ext4_li_mtx);
2912 }
2913
2914 static struct task_struct *ext4_lazyinit_task;
2915
2916 /*
2917  * This is the function where ext4lazyinit thread lives. It walks
2918  * through the request list searching for next scheduled filesystem.
2919  * When such a fs is found, run the lazy initialization request
2920  * (ext4_rn_li_request) and keep track of the time spend in this
2921  * function. Based on that time we compute next schedule time of
2922  * the request. When walking through the list is complete, compute
2923  * next waking time and put itself into sleep.
2924  */
2925 static int ext4_lazyinit_thread(void *arg)
2926 {
2927         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2928         struct list_head *pos, *n;
2929         struct ext4_li_request *elr;
2930         unsigned long next_wakeup, cur;
2931
2932         BUG_ON(NULL == eli);
2933
2934 cont_thread:
2935         while (true) {
2936                 next_wakeup = MAX_JIFFY_OFFSET;
2937
2938                 mutex_lock(&eli->li_list_mtx);
2939                 if (list_empty(&eli->li_request_list)) {
2940                         mutex_unlock(&eli->li_list_mtx);
2941                         goto exit_thread;
2942                 }
2943                 list_for_each_safe(pos, n, &eli->li_request_list) {
2944                         int err = 0;
2945                         int progress = 0;
2946                         elr = list_entry(pos, struct ext4_li_request,
2947                                          lr_request);
2948
2949                         if (time_before(jiffies, elr->lr_next_sched)) {
2950                                 if (time_before(elr->lr_next_sched, next_wakeup))
2951                                         next_wakeup = elr->lr_next_sched;
2952                                 continue;
2953                         }
2954                         if (down_read_trylock(&elr->lr_super->s_umount)) {
2955                                 if (sb_start_write_trylock(elr->lr_super)) {
2956                                         progress = 1;
2957                                         /*
2958                                          * We hold sb->s_umount, sb can not
2959                                          * be removed from the list, it is
2960                                          * now safe to drop li_list_mtx
2961                                          */
2962                                         mutex_unlock(&eli->li_list_mtx);
2963                                         err = ext4_run_li_request(elr);
2964                                         sb_end_write(elr->lr_super);
2965                                         mutex_lock(&eli->li_list_mtx);
2966                                         n = pos->next;
2967                                 }
2968                                 up_read((&elr->lr_super->s_umount));
2969                         }
2970                         /* error, remove the lazy_init job */
2971                         if (err) {
2972                                 ext4_remove_li_request(elr);
2973                                 continue;
2974                         }
2975                         if (!progress) {
2976                                 elr->lr_next_sched = jiffies +
2977                                         (prandom_u32()
2978                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
2979                         }
2980                         if (time_before(elr->lr_next_sched, next_wakeup))
2981                                 next_wakeup = elr->lr_next_sched;
2982                 }
2983                 mutex_unlock(&eli->li_list_mtx);
2984
2985                 try_to_freeze();
2986
2987                 cur = jiffies;
2988                 if ((time_after_eq(cur, next_wakeup)) ||
2989                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2990                         cond_resched();
2991                         continue;
2992                 }
2993
2994                 schedule_timeout_interruptible(next_wakeup - cur);
2995
2996                 if (kthread_should_stop()) {
2997                         ext4_clear_request_list();
2998                         goto exit_thread;
2999                 }
3000         }
3001
3002 exit_thread:
3003         /*
3004          * It looks like the request list is empty, but we need
3005          * to check it under the li_list_mtx lock, to prevent any
3006          * additions into it, and of course we should lock ext4_li_mtx
3007          * to atomically free the list and ext4_li_info, because at
3008          * this point another ext4 filesystem could be registering
3009          * new one.
3010          */
3011         mutex_lock(&ext4_li_mtx);
3012         mutex_lock(&eli->li_list_mtx);
3013         if (!list_empty(&eli->li_request_list)) {
3014                 mutex_unlock(&eli->li_list_mtx);
3015                 mutex_unlock(&ext4_li_mtx);
3016                 goto cont_thread;
3017         }
3018         mutex_unlock(&eli->li_list_mtx);
3019         kfree(ext4_li_info);
3020         ext4_li_info = NULL;
3021         mutex_unlock(&ext4_li_mtx);
3022
3023         return 0;
3024 }
3025
3026 static void ext4_clear_request_list(void)
3027 {
3028         struct list_head *pos, *n;
3029         struct ext4_li_request *elr;
3030
3031         mutex_lock(&ext4_li_info->li_list_mtx);
3032         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3033                 elr = list_entry(pos, struct ext4_li_request,
3034                                  lr_request);
3035                 ext4_remove_li_request(elr);
3036         }
3037         mutex_unlock(&ext4_li_info->li_list_mtx);
3038 }
3039
3040 static int ext4_run_lazyinit_thread(void)
3041 {
3042         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3043                                          ext4_li_info, "ext4lazyinit");
3044         if (IS_ERR(ext4_lazyinit_task)) {
3045                 int err = PTR_ERR(ext4_lazyinit_task);
3046                 ext4_clear_request_list();
3047                 kfree(ext4_li_info);
3048                 ext4_li_info = NULL;
3049                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3050                                  "initialization thread\n",
3051                                  err);
3052                 return err;
3053         }
3054         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3055         return 0;
3056 }
3057
3058 /*
3059  * Check whether it make sense to run itable init. thread or not.
3060  * If there is at least one uninitialized inode table, return
3061  * corresponding group number, else the loop goes through all
3062  * groups and return total number of groups.
3063  */
3064 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3065 {
3066         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3067         struct ext4_group_desc *gdp = NULL;
3068
3069         for (group = 0; group < ngroups; group++) {
3070                 gdp = ext4_get_group_desc(sb, group, NULL);
3071                 if (!gdp)
3072                         continue;
3073
3074                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3075                         break;
3076         }
3077
3078         return group;
3079 }
3080
3081 static int ext4_li_info_new(void)
3082 {
3083         struct ext4_lazy_init *eli = NULL;
3084
3085         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3086         if (!eli)
3087                 return -ENOMEM;
3088
3089         INIT_LIST_HEAD(&eli->li_request_list);
3090         mutex_init(&eli->li_list_mtx);
3091
3092         eli->li_state |= EXT4_LAZYINIT_QUIT;
3093
3094         ext4_li_info = eli;
3095
3096         return 0;
3097 }
3098
3099 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3100                                             ext4_group_t start)
3101 {
3102         struct ext4_sb_info *sbi = EXT4_SB(sb);
3103         struct ext4_li_request *elr;
3104
3105         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3106         if (!elr)
3107                 return NULL;
3108
3109         elr->lr_super = sb;
3110         elr->lr_sbi = sbi;
3111         elr->lr_next_group = start;
3112
3113         /*
3114          * Randomize first schedule time of the request to
3115          * spread the inode table initialization requests
3116          * better.
3117          */
3118         elr->lr_next_sched = jiffies + (prandom_u32() %
3119                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3120         return elr;
3121 }
3122
3123 int ext4_register_li_request(struct super_block *sb,
3124                              ext4_group_t first_not_zeroed)
3125 {
3126         struct ext4_sb_info *sbi = EXT4_SB(sb);
3127         struct ext4_li_request *elr = NULL;
3128         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3129         int ret = 0;
3130
3131         mutex_lock(&ext4_li_mtx);
3132         if (sbi->s_li_request != NULL) {
3133                 /*
3134                  * Reset timeout so it can be computed again, because
3135                  * s_li_wait_mult might have changed.
3136                  */
3137                 sbi->s_li_request->lr_timeout = 0;
3138                 goto out;
3139         }
3140
3141         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3142             !test_opt(sb, INIT_INODE_TABLE))
3143                 goto out;
3144
3145         elr = ext4_li_request_new(sb, first_not_zeroed);
3146         if (!elr) {
3147                 ret = -ENOMEM;
3148                 goto out;
3149         }
3150
3151         if (NULL == ext4_li_info) {
3152                 ret = ext4_li_info_new();
3153                 if (ret)
3154                         goto out;
3155         }
3156
3157         mutex_lock(&ext4_li_info->li_list_mtx);
3158         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3159         mutex_unlock(&ext4_li_info->li_list_mtx);
3160
3161         sbi->s_li_request = elr;
3162         /*
3163          * set elr to NULL here since it has been inserted to
3164          * the request_list and the removal and free of it is
3165          * handled by ext4_clear_request_list from now on.
3166          */
3167         elr = NULL;
3168
3169         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3170                 ret = ext4_run_lazyinit_thread();
3171                 if (ret)
3172                         goto out;
3173         }
3174 out:
3175         mutex_unlock(&ext4_li_mtx);
3176         if (ret)
3177                 kfree(elr);
3178         return ret;
3179 }
3180
3181 /*
3182  * We do not need to lock anything since this is called on
3183  * module unload.
3184  */
3185 static void ext4_destroy_lazyinit_thread(void)
3186 {
3187         /*
3188          * If thread exited earlier
3189          * there's nothing to be done.
3190          */
3191         if (!ext4_li_info || !ext4_lazyinit_task)
3192                 return;
3193
3194         kthread_stop(ext4_lazyinit_task);
3195 }
3196
3197 static int set_journal_csum_feature_set(struct super_block *sb)
3198 {
3199         int ret = 1;
3200         int compat, incompat;
3201         struct ext4_sb_info *sbi = EXT4_SB(sb);
3202
3203         if (ext4_has_metadata_csum(sb)) {
3204                 /* journal checksum v3 */
3205                 compat = 0;
3206                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3207         } else {
3208                 /* journal checksum v1 */
3209                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3210                 incompat = 0;
3211         }
3212
3213         jbd2_journal_clear_features(sbi->s_journal,
3214                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3215                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3216                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3217         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3218                 ret = jbd2_journal_set_features(sbi->s_journal,
3219                                 compat, 0,
3220                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3221                                 incompat);
3222         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3223                 ret = jbd2_journal_set_features(sbi->s_journal,
3224                                 compat, 0,
3225                                 incompat);
3226                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3227                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3228         } else {
3229                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3230                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3231         }
3232
3233         return ret;
3234 }
3235
3236 /*
3237  * Note: calculating the overhead so we can be compatible with
3238  * historical BSD practice is quite difficult in the face of
3239  * clusters/bigalloc.  This is because multiple metadata blocks from
3240  * different block group can end up in the same allocation cluster.
3241  * Calculating the exact overhead in the face of clustered allocation
3242  * requires either O(all block bitmaps) in memory or O(number of block
3243  * groups**2) in time.  We will still calculate the superblock for
3244  * older file systems --- and if we come across with a bigalloc file
3245  * system with zero in s_overhead_clusters the estimate will be close to
3246  * correct especially for very large cluster sizes --- but for newer
3247  * file systems, it's better to calculate this figure once at mkfs
3248  * time, and store it in the superblock.  If the superblock value is
3249  * present (even for non-bigalloc file systems), we will use it.
3250  */
3251 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3252                           char *buf)
3253 {
3254         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3255         struct ext4_group_desc  *gdp;
3256         ext4_fsblk_t            first_block, last_block, b;
3257         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3258         int                     s, j, count = 0;
3259
3260         if (!ext4_has_feature_bigalloc(sb))
3261                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3262                         sbi->s_itb_per_group + 2);
3263
3264         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3265                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3266         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3267         for (i = 0; i < ngroups; i++) {
3268                 gdp = ext4_get_group_desc(sb, i, NULL);
3269                 b = ext4_block_bitmap(sb, gdp);
3270                 if (b >= first_block && b <= last_block) {
3271                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3272                         count++;
3273                 }
3274                 b = ext4_inode_bitmap(sb, gdp);
3275                 if (b >= first_block && b <= last_block) {
3276                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3277                         count++;
3278                 }
3279                 b = ext4_inode_table(sb, gdp);
3280                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3281                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3282                                 int c = EXT4_B2C(sbi, b - first_block);
3283                                 ext4_set_bit(c, buf);
3284                                 count++;
3285                         }
3286                 if (i != grp)
3287                         continue;
3288                 s = 0;
3289                 if (ext4_bg_has_super(sb, grp)) {
3290                         ext4_set_bit(s++, buf);
3291                         count++;
3292                 }
3293                 j = ext4_bg_num_gdb(sb, grp);
3294                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3295                         ext4_error(sb, "Invalid number of block group "
3296                                    "descriptor blocks: %d", j);
3297                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3298                 }
3299                 count += j;
3300                 for (; j > 0; j--)
3301                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3302         }
3303         if (!count)
3304                 return 0;
3305         return EXT4_CLUSTERS_PER_GROUP(sb) -
3306                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3307 }
3308
3309 /*
3310  * Compute the overhead and stash it in sbi->s_overhead
3311  */
3312 int ext4_calculate_overhead(struct super_block *sb)
3313 {
3314         struct ext4_sb_info *sbi = EXT4_SB(sb);
3315         struct ext4_super_block *es = sbi->s_es;
3316         struct inode *j_inode;
3317         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3318         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3319         ext4_fsblk_t overhead = 0;
3320         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3321
3322         if (!buf)
3323                 return -ENOMEM;
3324
3325         /*
3326          * Compute the overhead (FS structures).  This is constant
3327          * for a given filesystem unless the number of block groups
3328          * changes so we cache the previous value until it does.
3329          */
3330
3331         /*
3332          * All of the blocks before first_data_block are overhead
3333          */
3334         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3335
3336         /*
3337          * Add the overhead found in each block group
3338          */
3339         for (i = 0; i < ngroups; i++) {
3340                 int blks;
3341
3342                 blks = count_overhead(sb, i, buf);
3343                 overhead += blks;
3344                 if (blks)
3345                         memset(buf, 0, PAGE_SIZE);
3346                 cond_resched();
3347         }
3348
3349         /*
3350          * Add the internal journal blocks whether the journal has been
3351          * loaded or not
3352          */
3353         if (sbi->s_journal && !sbi->journal_bdev)
3354                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3355         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3356                 j_inode = ext4_get_journal_inode(sb, j_inum);
3357                 if (j_inode) {
3358                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3359                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3360                         iput(j_inode);
3361                 } else {
3362                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3363                 }
3364         }
3365         sbi->s_overhead = overhead;
3366         smp_wmb();
3367         free_page((unsigned long) buf);
3368         return 0;
3369 }
3370
3371 static void ext4_set_resv_clusters(struct super_block *sb)
3372 {
3373         ext4_fsblk_t resv_clusters;
3374         struct ext4_sb_info *sbi = EXT4_SB(sb);
3375
3376         /*
3377          * There's no need to reserve anything when we aren't using extents.
3378          * The space estimates are exact, there are no unwritten extents,
3379          * hole punching doesn't need new metadata... This is needed especially
3380          * to keep ext2/3 backward compatibility.
3381          */
3382         if (!ext4_has_feature_extents(sb))
3383                 return;
3384         /*
3385          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3386          * This should cover the situations where we can not afford to run
3387          * out of space like for example punch hole, or converting
3388          * unwritten extents in delalloc path. In most cases such
3389          * allocation would require 1, or 2 blocks, higher numbers are
3390          * very rare.
3391          */
3392         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3393                          sbi->s_cluster_bits);
3394
3395         do_div(resv_clusters, 50);
3396         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3397
3398         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3399 }
3400
3401 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3402 {
3403         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3404         char *orig_data = kstrdup(data, GFP_KERNEL);
3405         struct buffer_head *bh;
3406         struct ext4_super_block *es = NULL;
3407         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3408         ext4_fsblk_t block;
3409         ext4_fsblk_t sb_block = get_sb_block(&data);
3410         ext4_fsblk_t logical_sb_block;
3411         unsigned long offset = 0;
3412         unsigned long journal_devnum = 0;
3413         unsigned long def_mount_opts;
3414         struct inode *root;
3415         const char *descr;
3416         int ret = -ENOMEM;
3417         int blocksize, clustersize;
3418         unsigned int db_count;
3419         unsigned int i;
3420         int needs_recovery, has_huge_files, has_bigalloc;
3421         __u64 blocks_count;
3422         int err = 0;
3423         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3424         ext4_group_t first_not_zeroed;
3425
3426         if ((data && !orig_data) || !sbi)
3427                 goto out_free_base;
3428
3429         sbi->s_daxdev = dax_dev;
3430         sbi->s_blockgroup_lock =
3431                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3432         if (!sbi->s_blockgroup_lock)
3433                 goto out_free_base;
3434
3435         sb->s_fs_info = sbi;
3436         sbi->s_sb = sb;
3437         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3438         sbi->s_sb_block = sb_block;
3439         if (sb->s_bdev->bd_part)
3440                 sbi->s_sectors_written_start =
3441                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3442
3443         /* Cleanup superblock name */
3444         strreplace(sb->s_id, '/', '!');
3445
3446         /* -EINVAL is default */
3447         ret = -EINVAL;
3448         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3449         if (!blocksize) {
3450                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3451                 goto out_fail;
3452         }
3453
3454         /*
3455          * The ext4 superblock will not be buffer aligned for other than 1kB
3456          * block sizes.  We need to calculate the offset from buffer start.
3457          */
3458         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3459                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3460                 offset = do_div(logical_sb_block, blocksize);
3461         } else {
3462                 logical_sb_block = sb_block;
3463         }
3464
3465         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3466                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3467                 goto out_fail;
3468         }
3469         /*
3470          * Note: s_es must be initialized as soon as possible because
3471          *       some ext4 macro-instructions depend on its value
3472          */
3473         es = (struct ext4_super_block *) (bh->b_data + offset);
3474         sbi->s_es = es;
3475         sb->s_magic = le16_to_cpu(es->s_magic);
3476         if (sb->s_magic != EXT4_SUPER_MAGIC)
3477                 goto cantfind_ext4;
3478         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3479
3480         /* Warn if metadata_csum and gdt_csum are both set. */
3481         if (ext4_has_feature_metadata_csum(sb) &&
3482             ext4_has_feature_gdt_csum(sb))
3483                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3484                              "redundant flags; please run fsck.");
3485
3486         /* Check for a known checksum algorithm */
3487         if (!ext4_verify_csum_type(sb, es)) {
3488                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3489                          "unknown checksum algorithm.");
3490                 silent = 1;
3491                 goto cantfind_ext4;
3492         }
3493
3494         /* Load the checksum driver */
3495         if (ext4_has_feature_metadata_csum(sb) ||
3496             ext4_has_feature_ea_inode(sb)) {
3497                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3498                 if (IS_ERR(sbi->s_chksum_driver)) {
3499                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3500                         ret = PTR_ERR(sbi->s_chksum_driver);
3501                         sbi->s_chksum_driver = NULL;
3502                         goto failed_mount;
3503                 }
3504         }
3505
3506         /* Check superblock checksum */
3507         if (!ext4_superblock_csum_verify(sb, es)) {
3508                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3509                          "invalid superblock checksum.  Run e2fsck?");
3510                 silent = 1;
3511                 ret = -EFSBADCRC;
3512                 goto cantfind_ext4;
3513         }
3514
3515         /* Precompute checksum seed for all metadata */
3516         if (ext4_has_feature_csum_seed(sb))
3517                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3518         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3519                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3520                                                sizeof(es->s_uuid));
3521
3522         /* Set defaults before we parse the mount options */
3523         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3524         set_opt(sb, INIT_INODE_TABLE);
3525         if (def_mount_opts & EXT4_DEFM_DEBUG)
3526                 set_opt(sb, DEBUG);
3527         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3528                 set_opt(sb, GRPID);
3529         if (def_mount_opts & EXT4_DEFM_UID16)
3530                 set_opt(sb, NO_UID32);
3531         /* xattr user namespace & acls are now defaulted on */
3532         set_opt(sb, XATTR_USER);
3533 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3534         set_opt(sb, POSIX_ACL);
3535 #endif
3536         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3537         if (ext4_has_metadata_csum(sb))
3538                 set_opt(sb, JOURNAL_CHECKSUM);
3539
3540         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3541                 set_opt(sb, JOURNAL_DATA);
3542         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3543                 set_opt(sb, ORDERED_DATA);
3544         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3545                 set_opt(sb, WRITEBACK_DATA);
3546
3547         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3548                 set_opt(sb, ERRORS_PANIC);
3549         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3550                 set_opt(sb, ERRORS_CONT);
3551         else
3552                 set_opt(sb, ERRORS_RO);
3553         /* block_validity enabled by default; disable with noblock_validity */
3554         set_opt(sb, BLOCK_VALIDITY);
3555         if (def_mount_opts & EXT4_DEFM_DISCARD)
3556                 set_opt(sb, DISCARD);
3557
3558         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3559         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3560         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3561         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3562         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3563
3564         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3565                 set_opt(sb, BARRIER);
3566
3567         /*
3568          * enable delayed allocation by default
3569          * Use -o nodelalloc to turn it off
3570          */
3571         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3572             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3573                 set_opt(sb, DELALLOC);
3574
3575         /*
3576          * set default s_li_wait_mult for lazyinit, for the case there is
3577          * no mount option specified.
3578          */
3579         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3580
3581         if (sbi->s_es->s_mount_opts[0]) {
3582                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3583                                               sizeof(sbi->s_es->s_mount_opts),
3584                                               GFP_KERNEL);
3585                 if (!s_mount_opts)
3586                         goto failed_mount;
3587                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3588                                    &journal_ioprio, 0)) {
3589                         ext4_msg(sb, KERN_WARNING,
3590                                  "failed to parse options in superblock: %s",
3591                                  s_mount_opts);
3592                 }
3593                 kfree(s_mount_opts);
3594         }
3595         sbi->s_def_mount_opt = sbi->s_mount_opt;
3596         if (!parse_options((char *) data, sb, &journal_devnum,
3597                            &journal_ioprio, 0))
3598                 goto failed_mount;
3599
3600         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3601                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3602                             "with data=journal disables delayed "
3603                             "allocation and O_DIRECT support!\n");
3604                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3605                         ext4_msg(sb, KERN_ERR, "can't mount with "
3606                                  "both data=journal and delalloc");
3607                         goto failed_mount;
3608                 }
3609                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3610                         ext4_msg(sb, KERN_ERR, "can't mount with "
3611                                  "both data=journal and dioread_nolock");
3612                         goto failed_mount;
3613                 }
3614                 if (test_opt(sb, DAX)) {
3615                         ext4_msg(sb, KERN_ERR, "can't mount with "
3616                                  "both data=journal and dax");
3617                         goto failed_mount;
3618                 }
3619                 if (ext4_has_feature_encrypt(sb)) {
3620                         ext4_msg(sb, KERN_WARNING,
3621                                  "encrypted files will use data=ordered "
3622                                  "instead of data journaling mode");
3623                 }
3624                 if (test_opt(sb, DELALLOC))
3625                         clear_opt(sb, DELALLOC);
3626         } else {
3627                 sb->s_iflags |= SB_I_CGROUPWB;
3628         }
3629
3630         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3631                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3632
3633         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3634             (ext4_has_compat_features(sb) ||
3635              ext4_has_ro_compat_features(sb) ||
3636              ext4_has_incompat_features(sb)))
3637                 ext4_msg(sb, KERN_WARNING,
3638                        "feature flags set on rev 0 fs, "
3639                        "running e2fsck is recommended");
3640
3641         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3642                 set_opt2(sb, HURD_COMPAT);
3643                 if (ext4_has_feature_64bit(sb)) {
3644                         ext4_msg(sb, KERN_ERR,
3645                                  "The Hurd can't support 64-bit file systems");
3646                         goto failed_mount;
3647                 }
3648
3649                 /*
3650                  * ea_inode feature uses l_i_version field which is not
3651                  * available in HURD_COMPAT mode.
3652                  */
3653                 if (ext4_has_feature_ea_inode(sb)) {
3654                         ext4_msg(sb, KERN_ERR,
3655                                  "ea_inode feature is not supported for Hurd");
3656                         goto failed_mount;
3657                 }
3658         }
3659
3660         if (IS_EXT2_SB(sb)) {
3661                 if (ext2_feature_set_ok(sb))
3662                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3663                                  "using the ext4 subsystem");
3664                 else {
3665                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3666                                  "to feature incompatibilities");
3667                         goto failed_mount;
3668                 }
3669         }
3670
3671         if (IS_EXT3_SB(sb)) {
3672                 if (ext3_feature_set_ok(sb))
3673                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3674                                  "using the ext4 subsystem");
3675                 else {
3676                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3677                                  "to feature incompatibilities");
3678                         goto failed_mount;
3679                 }
3680         }
3681
3682         /*
3683          * Check feature flags regardless of the revision level, since we
3684          * previously didn't change the revision level when setting the flags,
3685          * so there is a chance incompat flags are set on a rev 0 filesystem.
3686          */
3687         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3688                 goto failed_mount;
3689
3690         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3691         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3692             blocksize > EXT4_MAX_BLOCK_SIZE) {
3693                 ext4_msg(sb, KERN_ERR,
3694                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3695                          blocksize, le32_to_cpu(es->s_log_block_size));
3696                 goto failed_mount;
3697         }
3698         if (le32_to_cpu(es->s_log_block_size) >
3699             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3700                 ext4_msg(sb, KERN_ERR,
3701                          "Invalid log block size: %u",
3702                          le32_to_cpu(es->s_log_block_size));
3703                 goto failed_mount;
3704         }
3705
3706         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3707                 ext4_msg(sb, KERN_ERR,
3708                          "Number of reserved GDT blocks insanely large: %d",
3709                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3710                 goto failed_mount;
3711         }
3712
3713         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3714                 if (ext4_has_feature_inline_data(sb)) {
3715                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3716                                         " that may contain inline data");
3717                         goto failed_mount;
3718                 }
3719                 err = bdev_dax_supported(sb, blocksize);
3720                 if (err)
3721                         goto failed_mount;
3722         }
3723
3724         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3725                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3726                          es->s_encryption_level);
3727                 goto failed_mount;
3728         }
3729
3730         if (sb->s_blocksize != blocksize) {
3731                 /* Validate the filesystem blocksize */
3732                 if (!sb_set_blocksize(sb, blocksize)) {
3733                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3734                                         blocksize);
3735                         goto failed_mount;
3736                 }
3737
3738                 brelse(bh);
3739                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3740                 offset = do_div(logical_sb_block, blocksize);
3741                 bh = sb_bread_unmovable(sb, logical_sb_block);
3742                 if (!bh) {
3743                         ext4_msg(sb, KERN_ERR,
3744                                "Can't read superblock on 2nd try");
3745                         goto failed_mount;
3746                 }
3747                 es = (struct ext4_super_block *)(bh->b_data + offset);
3748                 sbi->s_es = es;
3749                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3750                         ext4_msg(sb, KERN_ERR,
3751                                "Magic mismatch, very weird!");
3752                         goto failed_mount;
3753                 }
3754         }
3755
3756         has_huge_files = ext4_has_feature_huge_file(sb);
3757         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3758                                                       has_huge_files);
3759         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3760
3761         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3762                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3763                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3764         } else {
3765                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3766                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3767                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3768                     (!is_power_of_2(sbi->s_inode_size)) ||
3769                     (sbi->s_inode_size > blocksize)) {
3770                         ext4_msg(sb, KERN_ERR,
3771                                "unsupported inode size: %d",
3772                                sbi->s_inode_size);
3773                         goto failed_mount;
3774                 }
3775                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3776                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3777         }
3778
3779         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3780         if (ext4_has_feature_64bit(sb)) {
3781                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3782                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3783                     !is_power_of_2(sbi->s_desc_size)) {
3784                         ext4_msg(sb, KERN_ERR,
3785                                "unsupported descriptor size %lu",
3786                                sbi->s_desc_size);
3787                         goto failed_mount;
3788                 }
3789         } else
3790                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3791
3792         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3793         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3794
3795         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3796         if (sbi->s_inodes_per_block == 0)
3797                 goto cantfind_ext4;
3798         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
3799             sbi->s_inodes_per_group > blocksize * 8) {
3800                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
3801                          sbi->s_blocks_per_group);
3802                 goto failed_mount;
3803         }
3804         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3805                                         sbi->s_inodes_per_block;
3806         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3807         sbi->s_sbh = bh;
3808         sbi->s_mount_state = le16_to_cpu(es->s_state);
3809         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3810         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3811
3812         for (i = 0; i < 4; i++)
3813                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3814         sbi->s_def_hash_version = es->s_def_hash_version;
3815         if (ext4_has_feature_dir_index(sb)) {
3816                 i = le32_to_cpu(es->s_flags);
3817                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3818                         sbi->s_hash_unsigned = 3;
3819                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3820 #ifdef __CHAR_UNSIGNED__
3821                         if (!sb_rdonly(sb))
3822                                 es->s_flags |=
3823                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3824                         sbi->s_hash_unsigned = 3;
3825 #else
3826                         if (!sb_rdonly(sb))
3827                                 es->s_flags |=
3828                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3829 #endif
3830                 }
3831         }
3832
3833         /* Handle clustersize */
3834         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3835         has_bigalloc = ext4_has_feature_bigalloc(sb);
3836         if (has_bigalloc) {
3837                 if (clustersize < blocksize) {
3838                         ext4_msg(sb, KERN_ERR,
3839                                  "cluster size (%d) smaller than "
3840                                  "block size (%d)", clustersize, blocksize);
3841                         goto failed_mount;
3842                 }
3843                 if (le32_to_cpu(es->s_log_cluster_size) >
3844                     (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3845                         ext4_msg(sb, KERN_ERR,
3846                                  "Invalid log cluster size: %u",
3847                                  le32_to_cpu(es->s_log_cluster_size));
3848                         goto failed_mount;
3849                 }
3850                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3851                         le32_to_cpu(es->s_log_block_size);
3852                 sbi->s_clusters_per_group =
3853                         le32_to_cpu(es->s_clusters_per_group);
3854                 if (sbi->s_clusters_per_group > blocksize * 8) {
3855                         ext4_msg(sb, KERN_ERR,
3856                                  "#clusters per group too big: %lu",
3857                                  sbi->s_clusters_per_group);
3858                         goto failed_mount;
3859                 }
3860                 if (sbi->s_blocks_per_group !=
3861                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3862                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3863                                  "clusters per group (%lu) inconsistent",
3864                                  sbi->s_blocks_per_group,
3865                                  sbi->s_clusters_per_group);
3866                         goto failed_mount;
3867                 }
3868         } else {
3869                 if (clustersize != blocksize) {
3870                         ext4_warning(sb, "fragment/cluster size (%d) != "
3871                                      "block size (%d)", clustersize,
3872                                      blocksize);
3873                         clustersize = blocksize;
3874                 }
3875                 if (sbi->s_blocks_per_group > blocksize * 8) {
3876                         ext4_msg(sb, KERN_ERR,
3877                                  "#blocks per group too big: %lu",
3878                                  sbi->s_blocks_per_group);
3879                         goto failed_mount;
3880                 }
3881                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3882                 sbi->s_cluster_bits = 0;
3883         }
3884         sbi->s_cluster_ratio = clustersize / blocksize;
3885
3886         /* Do we have standard group size of clustersize * 8 blocks ? */
3887         if (sbi->s_blocks_per_group == clustersize << 3)
3888                 set_opt2(sb, STD_GROUP_SIZE);
3889
3890         /*
3891          * Test whether we have more sectors than will fit in sector_t,
3892          * and whether the max offset is addressable by the page cache.
3893          */
3894         err = generic_check_addressable(sb->s_blocksize_bits,
3895                                         ext4_blocks_count(es));
3896         if (err) {
3897                 ext4_msg(sb, KERN_ERR, "filesystem"
3898                          " too large to mount safely on this system");
3899                 if (sizeof(sector_t) < 8)
3900                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3901                 goto failed_mount;
3902         }
3903
3904         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3905                 goto cantfind_ext4;
3906
3907         /* check blocks count against device size */
3908         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3909         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3910                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3911                        "exceeds size of device (%llu blocks)",
3912                        ext4_blocks_count(es), blocks_count);
3913                 goto failed_mount;
3914         }
3915
3916         /*
3917          * It makes no sense for the first data block to be beyond the end
3918          * of the filesystem.
3919          */
3920         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3921                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3922                          "block %u is beyond end of filesystem (%llu)",
3923                          le32_to_cpu(es->s_first_data_block),
3924                          ext4_blocks_count(es));
3925                 goto failed_mount;
3926         }
3927         blocks_count = (ext4_blocks_count(es) -
3928                         le32_to_cpu(es->s_first_data_block) +
3929                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3930         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3931         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3932                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3933                        "(block count %llu, first data block %u, "
3934                        "blocks per group %lu)", sbi->s_groups_count,
3935                        ext4_blocks_count(es),
3936                        le32_to_cpu(es->s_first_data_block),
3937                        EXT4_BLOCKS_PER_GROUP(sb));
3938                 goto failed_mount;
3939         }
3940         sbi->s_groups_count = blocks_count;
3941         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3942                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3943         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3944                    EXT4_DESC_PER_BLOCK(sb);
3945         if (ext4_has_feature_meta_bg(sb)) {
3946                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
3947                         ext4_msg(sb, KERN_WARNING,
3948                                  "first meta block group too large: %u "
3949                                  "(group descriptor block count %u)",
3950                                  le32_to_cpu(es->s_first_meta_bg), db_count);
3951                         goto failed_mount;
3952                 }
3953         }
3954         sbi->s_group_desc = kvmalloc(db_count *
3955                                           sizeof(struct buffer_head *),
3956                                           GFP_KERNEL);
3957         if (sbi->s_group_desc == NULL) {
3958                 ext4_msg(sb, KERN_ERR, "not enough memory");
3959                 ret = -ENOMEM;
3960                 goto failed_mount;
3961         }
3962
3963         bgl_lock_init(sbi->s_blockgroup_lock);
3964
3965         /* Pre-read the descriptors into the buffer cache */
3966         for (i = 0; i < db_count; i++) {
3967                 block = descriptor_loc(sb, logical_sb_block, i);
3968                 sb_breadahead(sb, block);
3969         }
3970
3971         for (i = 0; i < db_count; i++) {
3972                 block = descriptor_loc(sb, logical_sb_block, i);
3973                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3974                 if (!sbi->s_group_desc[i]) {
3975                         ext4_msg(sb, KERN_ERR,
3976                                "can't read group descriptor %d", i);
3977                         db_count = i;
3978                         goto failed_mount2;
3979                 }
3980         }
3981         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
3982                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3983                 ret = -EFSCORRUPTED;
3984                 goto failed_mount2;
3985         }
3986
3987         sbi->s_gdb_count = db_count;
3988         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3989         spin_lock_init(&sbi->s_next_gen_lock);
3990
3991         setup_timer(&sbi->s_err_report, print_daily_error_info,
3992                 (unsigned long) sb);
3993
3994         /* Register extent status tree shrinker */
3995         if (ext4_es_register_shrinker(sbi))
3996                 goto failed_mount3;
3997
3998         sbi->s_stripe = ext4_get_stripe_size(sbi);
3999         sbi->s_extent_max_zeroout_kb = 32;
4000
4001         /*
4002          * set up enough so that it can read an inode
4003          */
4004         sb->s_op = &ext4_sops;
4005         sb->s_export_op = &ext4_export_ops;
4006         sb->s_xattr = ext4_xattr_handlers;
4007         sb->s_cop = &ext4_cryptops;
4008 #ifdef CONFIG_QUOTA
4009         sb->dq_op = &ext4_quota_operations;
4010         if (ext4_has_feature_quota(sb))
4011                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4012         else
4013                 sb->s_qcop = &ext4_qctl_operations;
4014         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4015 #endif
4016         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4017
4018         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4019         mutex_init(&sbi->s_orphan_lock);
4020
4021         sb->s_root = NULL;
4022
4023         needs_recovery = (es->s_last_orphan != 0 ||
4024                           ext4_has_feature_journal_needs_recovery(sb));
4025
4026         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4027                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4028                         goto failed_mount3a;
4029
4030         /*
4031          * The first inode we look at is the journal inode.  Don't try
4032          * root first: it may be modified in the journal!
4033          */
4034         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4035                 err = ext4_load_journal(sb, es, journal_devnum);
4036                 if (err)
4037                         goto failed_mount3a;
4038         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4039                    ext4_has_feature_journal_needs_recovery(sb)) {
4040                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4041                        "suppressed and not mounted read-only");
4042                 goto failed_mount_wq;
4043         } else {
4044                 /* Nojournal mode, all journal mount options are illegal */
4045                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4046                         ext4_msg(sb, KERN_ERR, "can't mount with "
4047                                  "journal_checksum, fs mounted w/o journal");
4048                         goto failed_mount_wq;
4049                 }
4050                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4051                         ext4_msg(sb, KERN_ERR, "can't mount with "
4052                                  "journal_async_commit, fs mounted w/o journal");
4053                         goto failed_mount_wq;
4054                 }
4055                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4056                         ext4_msg(sb, KERN_ERR, "can't mount with "
4057                                  "commit=%lu, fs mounted w/o journal",
4058                                  sbi->s_commit_interval / HZ);
4059                         goto failed_mount_wq;
4060                 }
4061                 if (EXT4_MOUNT_DATA_FLAGS &
4062                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4063                         ext4_msg(sb, KERN_ERR, "can't mount with "
4064                                  "data=, fs mounted w/o journal");
4065                         goto failed_mount_wq;
4066                 }
4067                 sbi->s_def_mount_opt &= EXT4_MOUNT_JOURNAL_CHECKSUM;
4068                 clear_opt(sb, JOURNAL_CHECKSUM);
4069                 clear_opt(sb, DATA_FLAGS);
4070                 sbi->s_journal = NULL;
4071                 needs_recovery = 0;
4072                 goto no_journal;
4073         }
4074
4075         if (ext4_has_feature_64bit(sb) &&
4076             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4077                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4078                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4079                 goto failed_mount_wq;
4080         }
4081
4082         if (!set_journal_csum_feature_set(sb)) {
4083                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4084                          "feature set");
4085                 goto failed_mount_wq;
4086         }
4087
4088         /* We have now updated the journal if required, so we can
4089          * validate the data journaling mode. */
4090         switch (test_opt(sb, DATA_FLAGS)) {
4091         case 0:
4092                 /* No mode set, assume a default based on the journal
4093                  * capabilities: ORDERED_DATA if the journal can
4094                  * cope, else JOURNAL_DATA
4095                  */
4096                 if (jbd2_journal_check_available_features
4097                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
4098                         set_opt(sb, ORDERED_DATA);
4099                 else
4100                         set_opt(sb, JOURNAL_DATA);
4101                 break;
4102
4103         case EXT4_MOUNT_ORDERED_DATA:
4104         case EXT4_MOUNT_WRITEBACK_DATA:
4105                 if (!jbd2_journal_check_available_features
4106                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4107                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4108                                "requested data journaling mode");
4109                         goto failed_mount_wq;
4110                 }
4111         default:
4112                 break;
4113         }
4114
4115         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4116             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4117                 ext4_msg(sb, KERN_ERR, "can't mount with "
4118                         "journal_async_commit in data=ordered mode");
4119                 goto failed_mount_wq;
4120         }
4121
4122         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4123
4124         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4125
4126 no_journal:
4127         if (!test_opt(sb, NO_MBCACHE)) {
4128                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4129                 if (!sbi->s_ea_block_cache) {
4130                         ext4_msg(sb, KERN_ERR,
4131                                  "Failed to create ea_block_cache");
4132                         goto failed_mount_wq;
4133                 }
4134
4135                 if (ext4_has_feature_ea_inode(sb)) {
4136                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4137                         if (!sbi->s_ea_inode_cache) {
4138                                 ext4_msg(sb, KERN_ERR,
4139                                          "Failed to create ea_inode_cache");
4140                                 goto failed_mount_wq;
4141                         }
4142                 }
4143         }
4144
4145         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4146             (blocksize != PAGE_SIZE)) {
4147                 ext4_msg(sb, KERN_ERR,
4148                          "Unsupported blocksize for fs encryption");
4149                 goto failed_mount_wq;
4150         }
4151
4152         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4153             !ext4_has_feature_encrypt(sb)) {
4154                 ext4_set_feature_encrypt(sb);
4155                 ext4_commit_super(sb, 1);
4156         }
4157
4158         /*
4159          * Get the # of file system overhead blocks from the
4160          * superblock if present.
4161          */
4162         if (es->s_overhead_clusters)
4163                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4164         else {
4165                 err = ext4_calculate_overhead(sb);
4166                 if (err)
4167                         goto failed_mount_wq;
4168         }
4169
4170         /*
4171          * The maximum number of concurrent works can be high and
4172          * concurrency isn't really necessary.  Limit it to 1.
4173          */
4174         EXT4_SB(sb)->rsv_conversion_wq =
4175                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4176         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4177                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4178                 ret = -ENOMEM;
4179                 goto failed_mount4;
4180         }
4181
4182         /*
4183          * The jbd2_journal_load will have done any necessary log recovery,
4184          * so we can safely mount the rest of the filesystem now.
4185          */
4186
4187         root = ext4_iget(sb, EXT4_ROOT_INO);
4188         if (IS_ERR(root)) {
4189                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4190                 ret = PTR_ERR(root);
4191                 root = NULL;
4192                 goto failed_mount4;
4193         }
4194         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4195                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4196                 iput(root);
4197                 goto failed_mount4;
4198         }
4199         sb->s_root = d_make_root(root);
4200         if (!sb->s_root) {
4201                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4202                 ret = -ENOMEM;
4203                 goto failed_mount4;
4204         }
4205
4206         if (ext4_setup_super(sb, es, sb_rdonly(sb)))
4207                 sb->s_flags |= MS_RDONLY;
4208
4209         /* determine the minimum size of new large inodes, if present */
4210         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE &&
4211             sbi->s_want_extra_isize == 0) {
4212                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4213                                                      EXT4_GOOD_OLD_INODE_SIZE;
4214                 if (ext4_has_feature_extra_isize(sb)) {
4215                         if (sbi->s_want_extra_isize <
4216                             le16_to_cpu(es->s_want_extra_isize))
4217                                 sbi->s_want_extra_isize =
4218                                         le16_to_cpu(es->s_want_extra_isize);
4219                         if (sbi->s_want_extra_isize <
4220                             le16_to_cpu(es->s_min_extra_isize))
4221                                 sbi->s_want_extra_isize =
4222                                         le16_to_cpu(es->s_min_extra_isize);
4223                 }
4224         }
4225         /* Check if enough inode space is available */
4226         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4227                                                         sbi->s_inode_size) {
4228                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4229                                                        EXT4_GOOD_OLD_INODE_SIZE;
4230                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4231                          "available");
4232         }
4233
4234         ext4_set_resv_clusters(sb);
4235
4236         err = ext4_setup_system_zone(sb);
4237         if (err) {
4238                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4239                          "zone (%d)", err);
4240                 goto failed_mount4a;
4241         }
4242
4243         ext4_ext_init(sb);
4244         err = ext4_mb_init(sb);
4245         if (err) {
4246                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4247                          err);
4248                 goto failed_mount5;
4249         }
4250
4251         block = ext4_count_free_clusters(sb);
4252         ext4_free_blocks_count_set(sbi->s_es,
4253                                    EXT4_C2B(sbi, block));
4254         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4255                                   GFP_KERNEL);
4256         if (!err) {
4257                 unsigned long freei = ext4_count_free_inodes(sb);
4258                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4259                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4260                                           GFP_KERNEL);
4261         }
4262         if (!err)
4263                 err = percpu_counter_init(&sbi->s_dirs_counter,
4264                                           ext4_count_dirs(sb), GFP_KERNEL);
4265         if (!err)
4266                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4267                                           GFP_KERNEL);
4268         if (!err)
4269                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4270
4271         if (err) {
4272                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4273                 goto failed_mount6;
4274         }
4275
4276         if (ext4_has_feature_flex_bg(sb))
4277                 if (!ext4_fill_flex_info(sb)) {
4278                         ext4_msg(sb, KERN_ERR,
4279                                "unable to initialize "
4280                                "flex_bg meta info!");
4281                         goto failed_mount6;
4282                 }
4283
4284         err = ext4_register_li_request(sb, first_not_zeroed);
4285         if (err)
4286                 goto failed_mount6;
4287
4288         err = ext4_register_sysfs(sb);
4289         if (err)
4290                 goto failed_mount7;
4291
4292 #ifdef CONFIG_QUOTA
4293         /* Enable quota usage during mount. */
4294         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4295                 err = ext4_enable_quotas(sb);
4296                 if (err)
4297                         goto failed_mount8;
4298         }
4299 #endif  /* CONFIG_QUOTA */
4300
4301         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4302         ext4_orphan_cleanup(sb, es);
4303         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4304         if (needs_recovery) {
4305                 ext4_msg(sb, KERN_INFO, "recovery complete");
4306                 ext4_mark_recovery_complete(sb, es);
4307         }
4308         if (EXT4_SB(sb)->s_journal) {
4309                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4310                         descr = " journalled data mode";
4311                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4312                         descr = " ordered data mode";
4313                 else
4314                         descr = " writeback data mode";
4315         } else
4316                 descr = "out journal";
4317
4318         if (test_opt(sb, DISCARD)) {
4319                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4320                 if (!blk_queue_discard(q))
4321                         ext4_msg(sb, KERN_WARNING,
4322                                  "mounting with \"discard\" option, but "
4323                                  "the device does not support discard");
4324         }
4325
4326         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4327                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4328                          "Opts: %.*s%s%s", descr,
4329                          (int) sizeof(sbi->s_es->s_mount_opts),
4330                          sbi->s_es->s_mount_opts,
4331                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4332
4333         if (es->s_error_count)
4334                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4335
4336         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4337         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4338         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4339         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4340
4341         kfree(orig_data);
4342         return 0;
4343
4344 cantfind_ext4:
4345         if (!silent)
4346                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4347         goto failed_mount;
4348
4349 #ifdef CONFIG_QUOTA
4350 failed_mount8:
4351         ext4_unregister_sysfs(sb);
4352 #endif
4353 failed_mount7:
4354         ext4_unregister_li_request(sb);
4355 failed_mount6:
4356         ext4_mb_release(sb);
4357         if (sbi->s_flex_groups)
4358                 kvfree(sbi->s_flex_groups);
4359         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4360         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4361         percpu_counter_destroy(&sbi->s_dirs_counter);
4362         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4363 failed_mount5:
4364         ext4_ext_release(sb);
4365         ext4_release_system_zone(sb);
4366 failed_mount4a:
4367         dput(sb->s_root);
4368         sb->s_root = NULL;
4369 failed_mount4:
4370         ext4_msg(sb, KERN_ERR, "mount failed");
4371         if (EXT4_SB(sb)->rsv_conversion_wq)
4372                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4373 failed_mount_wq:
4374         if (sbi->s_ea_inode_cache) {
4375                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4376                 sbi->s_ea_inode_cache = NULL;
4377         }
4378         if (sbi->s_ea_block_cache) {
4379                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4380                 sbi->s_ea_block_cache = NULL;
4381         }
4382         if (sbi->s_journal) {
4383                 jbd2_journal_destroy(sbi->s_journal);
4384                 sbi->s_journal = NULL;
4385         }
4386 failed_mount3a:
4387         ext4_es_unregister_shrinker(sbi);
4388 failed_mount3:
4389         del_timer_sync(&sbi->s_err_report);
4390         if (sbi->s_mmp_tsk)
4391                 kthread_stop(sbi->s_mmp_tsk);
4392 failed_mount2:
4393         for (i = 0; i < db_count; i++)
4394                 brelse(sbi->s_group_desc[i]);
4395         kvfree(sbi->s_group_desc);
4396 failed_mount:
4397         if (sbi->s_chksum_driver)
4398                 crypto_free_shash(sbi->s_chksum_driver);
4399 #ifdef CONFIG_QUOTA
4400         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4401                 kfree(sbi->s_qf_names[i]);
4402 #endif
4403         ext4_blkdev_remove(sbi);
4404         brelse(bh);
4405 out_fail:
4406         sb->s_fs_info = NULL;
4407         kfree(sbi->s_blockgroup_lock);
4408 out_free_base:
4409         kfree(sbi);
4410         kfree(orig_data);
4411         fs_put_dax(dax_dev);
4412         return err ? err : ret;
4413 }
4414
4415 /*
4416  * Setup any per-fs journal parameters now.  We'll do this both on
4417  * initial mount, once the journal has been initialised but before we've
4418  * done any recovery; and again on any subsequent remount.
4419  */
4420 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4421 {
4422         struct ext4_sb_info *sbi = EXT4_SB(sb);
4423
4424         journal->j_commit_interval = sbi->s_commit_interval;
4425         journal->j_min_batch_time = sbi->s_min_batch_time;
4426         journal->j_max_batch_time = sbi->s_max_batch_time;
4427
4428         write_lock(&journal->j_state_lock);
4429         if (test_opt(sb, BARRIER))
4430                 journal->j_flags |= JBD2_BARRIER;
4431         else
4432                 journal->j_flags &= ~JBD2_BARRIER;
4433         if (test_opt(sb, DATA_ERR_ABORT))
4434                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4435         else
4436                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4437         write_unlock(&journal->j_state_lock);
4438 }
4439
4440 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4441                                              unsigned int journal_inum)
4442 {
4443         struct inode *journal_inode;
4444
4445         /*
4446          * Test for the existence of a valid inode on disk.  Bad things
4447          * happen if we iget() an unused inode, as the subsequent iput()
4448          * will try to delete it.
4449          */
4450         journal_inode = ext4_iget(sb, journal_inum);
4451         if (IS_ERR(journal_inode)) {
4452                 ext4_msg(sb, KERN_ERR, "no journal found");
4453                 return NULL;
4454         }
4455         if (!journal_inode->i_nlink) {
4456                 make_bad_inode(journal_inode);
4457                 iput(journal_inode);
4458                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4459                 return NULL;
4460         }
4461
4462         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4463                   journal_inode, journal_inode->i_size);
4464         if (!S_ISREG(journal_inode->i_mode)) {
4465                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4466                 iput(journal_inode);
4467                 return NULL;
4468         }
4469         return journal_inode;
4470 }
4471
4472 static journal_t *ext4_get_journal(struct super_block *sb,
4473                                    unsigned int journal_inum)
4474 {
4475         struct inode *journal_inode;
4476         journal_t *journal;
4477
4478         BUG_ON(!ext4_has_feature_journal(sb));
4479
4480         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4481         if (!journal_inode)
4482                 return NULL;
4483
4484         journal = jbd2_journal_init_inode(journal_inode);
4485         if (!journal) {
4486                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4487                 iput(journal_inode);
4488                 return NULL;
4489         }
4490         journal->j_private = sb;
4491         ext4_init_journal_params(sb, journal);
4492         return journal;
4493 }
4494
4495 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4496                                        dev_t j_dev)
4497 {
4498         struct buffer_head *bh;
4499         journal_t *journal;
4500         ext4_fsblk_t start;
4501         ext4_fsblk_t len;
4502         int hblock, blocksize;
4503         ext4_fsblk_t sb_block;
4504         unsigned long offset;
4505         struct ext4_super_block *es;
4506         struct block_device *bdev;
4507
4508         BUG_ON(!ext4_has_feature_journal(sb));
4509
4510         bdev = ext4_blkdev_get(j_dev, sb);
4511         if (bdev == NULL)
4512                 return NULL;
4513
4514         blocksize = sb->s_blocksize;
4515         hblock = bdev_logical_block_size(bdev);
4516         if (blocksize < hblock) {
4517                 ext4_msg(sb, KERN_ERR,
4518                         "blocksize too small for journal device");
4519                 goto out_bdev;
4520         }
4521
4522         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4523         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4524         set_blocksize(bdev, blocksize);
4525         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4526                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4527                        "external journal");
4528                 goto out_bdev;
4529         }
4530
4531         es = (struct ext4_super_block *) (bh->b_data + offset);
4532         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4533             !(le32_to_cpu(es->s_feature_incompat) &
4534               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4535                 ext4_msg(sb, KERN_ERR, "external journal has "
4536                                         "bad superblock");
4537                 brelse(bh);
4538                 goto out_bdev;
4539         }
4540
4541         if ((le32_to_cpu(es->s_feature_ro_compat) &
4542              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4543             es->s_checksum != ext4_superblock_csum(sb, es)) {
4544                 ext4_msg(sb, KERN_ERR, "external journal has "
4545                                        "corrupt superblock");
4546                 brelse(bh);
4547                 goto out_bdev;
4548         }
4549
4550         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4551                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4552                 brelse(bh);
4553                 goto out_bdev;
4554         }
4555
4556         len = ext4_blocks_count(es);
4557         start = sb_block + 1;
4558         brelse(bh);     /* we're done with the superblock */
4559
4560         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4561                                         start, len, blocksize);
4562         if (!journal) {
4563                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4564                 goto out_bdev;
4565         }
4566         journal->j_private = sb;
4567         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4568         wait_on_buffer(journal->j_sb_buffer);
4569         if (!buffer_uptodate(journal->j_sb_buffer)) {
4570                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4571                 goto out_journal;
4572         }
4573         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4574                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4575                                         "user (unsupported) - %d",
4576                         be32_to_cpu(journal->j_superblock->s_nr_users));
4577                 goto out_journal;
4578         }
4579         EXT4_SB(sb)->journal_bdev = bdev;
4580         ext4_init_journal_params(sb, journal);
4581         return journal;
4582
4583 out_journal:
4584         jbd2_journal_destroy(journal);
4585 out_bdev:
4586         ext4_blkdev_put(bdev);
4587         return NULL;
4588 }
4589
4590 static int ext4_load_journal(struct super_block *sb,
4591                              struct ext4_super_block *es,
4592                              unsigned long journal_devnum)
4593 {
4594         journal_t *journal;
4595         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4596         dev_t journal_dev;
4597         int err = 0;
4598         int really_read_only;
4599
4600         BUG_ON(!ext4_has_feature_journal(sb));
4601
4602         if (journal_devnum &&
4603             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4604                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4605                         "numbers have changed");
4606                 journal_dev = new_decode_dev(journal_devnum);
4607         } else
4608                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4609
4610         really_read_only = bdev_read_only(sb->s_bdev);
4611
4612         /*
4613          * Are we loading a blank journal or performing recovery after a
4614          * crash?  For recovery, we need to check in advance whether we
4615          * can get read-write access to the device.
4616          */
4617         if (ext4_has_feature_journal_needs_recovery(sb)) {
4618                 if (sb_rdonly(sb)) {
4619                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4620                                         "required on readonly filesystem");
4621                         if (really_read_only) {
4622                                 ext4_msg(sb, KERN_ERR, "write access "
4623                                         "unavailable, cannot proceed");
4624                                 return -EROFS;
4625                         }
4626                         ext4_msg(sb, KERN_INFO, "write access will "
4627                                "be enabled during recovery");
4628                 }
4629         }
4630
4631         if (journal_inum && journal_dev) {
4632                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4633                        "and inode journals!");
4634                 return -EINVAL;
4635         }
4636
4637         if (journal_inum) {
4638                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4639                         return -EINVAL;
4640         } else {
4641                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4642                         return -EINVAL;
4643         }
4644
4645         if (!(journal->j_flags & JBD2_BARRIER))
4646                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4647
4648         if (!ext4_has_feature_journal_needs_recovery(sb))
4649                 err = jbd2_journal_wipe(journal, !really_read_only);
4650         if (!err) {
4651                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4652                 if (save)
4653                         memcpy(save, ((char *) es) +
4654                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4655                 err = jbd2_journal_load(journal);
4656                 if (save)
4657                         memcpy(((char *) es) + EXT4_S_ERR_START,
4658                                save, EXT4_S_ERR_LEN);
4659                 kfree(save);
4660         }
4661
4662         if (err) {
4663                 ext4_msg(sb, KERN_ERR, "error loading journal");
4664                 jbd2_journal_destroy(journal);
4665                 return err;
4666         }
4667
4668         EXT4_SB(sb)->s_journal = journal;
4669         ext4_clear_journal_err(sb, es);
4670
4671         if (!really_read_only && journal_devnum &&
4672             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4673                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4674
4675                 /* Make sure we flush the recovery flag to disk. */
4676                 ext4_commit_super(sb, 1);
4677         }
4678
4679         return 0;
4680 }
4681
4682 static int ext4_commit_super(struct super_block *sb, int sync)
4683 {
4684         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4685         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4686         int error = 0;
4687
4688         if (!sbh || block_device_ejected(sb))
4689                 return error;
4690         /*
4691          * If the file system is mounted read-only, don't update the
4692          * superblock write time.  This avoids updating the superblock
4693          * write time when we are mounting the root file system
4694          * read/only but we need to replay the journal; at that point,
4695          * for people who are east of GMT and who make their clock
4696          * tick in localtime for Windows bug-for-bug compatibility,
4697          * the clock is set in the future, and this will cause e2fsck
4698          * to complain and force a full file system check.
4699          */
4700         if (!(sb->s_flags & MS_RDONLY))
4701                 es->s_wtime = cpu_to_le32(get_seconds());
4702         if (sb->s_bdev->bd_part)
4703                 es->s_kbytes_written =
4704                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4705                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4706                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4707         else
4708                 es->s_kbytes_written =
4709                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4710         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4711                 ext4_free_blocks_count_set(es,
4712                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4713                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4714         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4715                 es->s_free_inodes_count =
4716                         cpu_to_le32(percpu_counter_sum_positive(
4717                                 &EXT4_SB(sb)->s_freeinodes_counter));
4718         BUFFER_TRACE(sbh, "marking dirty");
4719         ext4_superblock_csum_set(sb);
4720         if (sync)
4721                 lock_buffer(sbh);
4722         if (buffer_write_io_error(sbh)) {
4723                 /*
4724                  * Oh, dear.  A previous attempt to write the
4725                  * superblock failed.  This could happen because the
4726                  * USB device was yanked out.  Or it could happen to
4727                  * be a transient write error and maybe the block will
4728                  * be remapped.  Nothing we can do but to retry the
4729                  * write and hope for the best.
4730                  */
4731                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4732                        "superblock detected");
4733                 clear_buffer_write_io_error(sbh);
4734                 set_buffer_uptodate(sbh);
4735         }
4736         mark_buffer_dirty(sbh);
4737         if (sync) {
4738                 unlock_buffer(sbh);
4739                 error = __sync_dirty_buffer(sbh,
4740                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
4741                 if (error)
4742                         return error;
4743
4744                 error = buffer_write_io_error(sbh);
4745                 if (error) {
4746                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4747                                "superblock");
4748                         clear_buffer_write_io_error(sbh);
4749                         set_buffer_uptodate(sbh);
4750                 }
4751         }
4752         return error;
4753 }
4754
4755 /*
4756  * Have we just finished recovery?  If so, and if we are mounting (or
4757  * remounting) the filesystem readonly, then we will end up with a
4758  * consistent fs on disk.  Record that fact.
4759  */
4760 static void ext4_mark_recovery_complete(struct super_block *sb,
4761                                         struct ext4_super_block *es)
4762 {
4763         journal_t *journal = EXT4_SB(sb)->s_journal;
4764
4765         if (!ext4_has_feature_journal(sb)) {
4766                 BUG_ON(journal != NULL);
4767                 return;
4768         }
4769         jbd2_journal_lock_updates(journal);
4770         if (jbd2_journal_flush(journal) < 0)
4771                 goto out;
4772
4773         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
4774                 ext4_clear_feature_journal_needs_recovery(sb);
4775                 ext4_commit_super(sb, 1);
4776         }
4777
4778 out:
4779         jbd2_journal_unlock_updates(journal);
4780 }
4781
4782 /*
4783  * If we are mounting (or read-write remounting) a filesystem whose journal
4784  * has recorded an error from a previous lifetime, move that error to the
4785  * main filesystem now.
4786  */
4787 static void ext4_clear_journal_err(struct super_block *sb,
4788                                    struct ext4_super_block *es)
4789 {
4790         journal_t *journal;
4791         int j_errno;
4792         const char *errstr;
4793
4794         BUG_ON(!ext4_has_feature_journal(sb));
4795
4796         journal = EXT4_SB(sb)->s_journal;
4797
4798         /*
4799          * Now check for any error status which may have been recorded in the
4800          * journal by a prior ext4_error() or ext4_abort()
4801          */
4802
4803         j_errno = jbd2_journal_errno(journal);
4804         if (j_errno) {
4805                 char nbuf[16];
4806
4807                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4808                 ext4_warning(sb, "Filesystem error recorded "
4809                              "from previous mount: %s", errstr);
4810                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4811
4812                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4813                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4814                 ext4_commit_super(sb, 1);
4815
4816                 jbd2_journal_clear_err(journal);
4817                 jbd2_journal_update_sb_errno(journal);
4818         }
4819 }
4820
4821 /*
4822  * Force the running and committing transactions to commit,
4823  * and wait on the commit.
4824  */
4825 int ext4_force_commit(struct super_block *sb)
4826 {
4827         journal_t *journal;
4828
4829         if (sb_rdonly(sb))
4830                 return 0;
4831
4832         journal = EXT4_SB(sb)->s_journal;
4833         return ext4_journal_force_commit(journal);
4834 }
4835
4836 static int ext4_sync_fs(struct super_block *sb, int wait)
4837 {
4838         int ret = 0;
4839         tid_t target;
4840         bool needs_barrier = false;
4841         struct ext4_sb_info *sbi = EXT4_SB(sb);
4842
4843         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
4844                 return 0;
4845
4846         trace_ext4_sync_fs(sb, wait);
4847         flush_workqueue(sbi->rsv_conversion_wq);
4848         /*
4849          * Writeback quota in non-journalled quota case - journalled quota has
4850          * no dirty dquots
4851          */
4852         dquot_writeback_dquots(sb, -1);
4853         /*
4854          * Data writeback is possible w/o journal transaction, so barrier must
4855          * being sent at the end of the function. But we can skip it if
4856          * transaction_commit will do it for us.
4857          */
4858         if (sbi->s_journal) {
4859                 target = jbd2_get_latest_transaction(sbi->s_journal);
4860                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4861                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4862                         needs_barrier = true;
4863
4864                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4865                         if (wait)
4866                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4867                                                            target);
4868                 }
4869         } else if (wait && test_opt(sb, BARRIER))
4870                 needs_barrier = true;
4871         if (needs_barrier) {
4872                 int err;
4873                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4874                 if (!ret)
4875                         ret = err;
4876         }
4877
4878         return ret;
4879 }
4880
4881 /*
4882  * LVM calls this function before a (read-only) snapshot is created.  This
4883  * gives us a chance to flush the journal completely and mark the fs clean.
4884  *
4885  * Note that only this function cannot bring a filesystem to be in a clean
4886  * state independently. It relies on upper layer to stop all data & metadata
4887  * modifications.
4888  */
4889 static int ext4_freeze(struct super_block *sb)
4890 {
4891         int error = 0;
4892         journal_t *journal;
4893
4894         if (sb_rdonly(sb))
4895                 return 0;
4896
4897         journal = EXT4_SB(sb)->s_journal;
4898
4899         if (journal) {
4900                 /* Now we set up the journal barrier. */
4901                 jbd2_journal_lock_updates(journal);
4902
4903                 /*
4904                  * Don't clear the needs_recovery flag if we failed to
4905                  * flush the journal.
4906                  */
4907                 error = jbd2_journal_flush(journal);
4908                 if (error < 0)
4909                         goto out;
4910
4911                 /* Journal blocked and flushed, clear needs_recovery flag. */
4912                 ext4_clear_feature_journal_needs_recovery(sb);
4913         }
4914
4915         error = ext4_commit_super(sb, 1);
4916 out:
4917         if (journal)
4918                 /* we rely on upper layer to stop further updates */
4919                 jbd2_journal_unlock_updates(journal);
4920         return error;
4921 }
4922
4923 /*
4924  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4925  * flag here, even though the filesystem is not technically dirty yet.
4926  */
4927 static int ext4_unfreeze(struct super_block *sb)
4928 {
4929         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
4930                 return 0;
4931
4932         if (EXT4_SB(sb)->s_journal) {
4933                 /* Reset the needs_recovery flag before the fs is unlocked. */
4934                 ext4_set_feature_journal_needs_recovery(sb);
4935         }
4936
4937         ext4_commit_super(sb, 1);
4938         return 0;
4939 }
4940
4941 /*
4942  * Structure to save mount options for ext4_remount's benefit
4943  */
4944 struct ext4_mount_options {
4945         unsigned long s_mount_opt;
4946         unsigned long s_mount_opt2;
4947         kuid_t s_resuid;
4948         kgid_t s_resgid;
4949         unsigned long s_commit_interval;
4950         u32 s_min_batch_time, s_max_batch_time;
4951 #ifdef CONFIG_QUOTA
4952         int s_jquota_fmt;
4953         char *s_qf_names[EXT4_MAXQUOTAS];
4954 #endif
4955 };
4956
4957 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4958 {
4959         struct ext4_super_block *es;
4960         struct ext4_sb_info *sbi = EXT4_SB(sb);
4961         unsigned long old_sb_flags;
4962         struct ext4_mount_options old_opts;
4963         int enable_quota = 0;
4964         ext4_group_t g;
4965         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4966         int err = 0;
4967 #ifdef CONFIG_QUOTA
4968         int i, j;
4969 #endif
4970         char *orig_data = kstrdup(data, GFP_KERNEL);
4971
4972         /* Store the original options */
4973         old_sb_flags = sb->s_flags;
4974         old_opts.s_mount_opt = sbi->s_mount_opt;
4975         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4976         old_opts.s_resuid = sbi->s_resuid;
4977         old_opts.s_resgid = sbi->s_resgid;
4978         old_opts.s_commit_interval = sbi->s_commit_interval;
4979         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4980         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4981 #ifdef CONFIG_QUOTA
4982         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4983         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4984                 if (sbi->s_qf_names[i]) {
4985                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4986                                                          GFP_KERNEL);
4987                         if (!old_opts.s_qf_names[i]) {
4988                                 for (j = 0; j < i; j++)
4989                                         kfree(old_opts.s_qf_names[j]);
4990                                 kfree(orig_data);
4991                                 return -ENOMEM;
4992                         }
4993                 } else
4994                         old_opts.s_qf_names[i] = NULL;
4995 #endif
4996         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4997                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4998
4999         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5000                 err = -EINVAL;
5001                 goto restore_opts;
5002         }
5003
5004         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5005             test_opt(sb, JOURNAL_CHECKSUM)) {
5006                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5007                          "during remount not supported; ignoring");
5008                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5009         }
5010
5011         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5012                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5013                         ext4_msg(sb, KERN_ERR, "can't mount with "
5014                                  "both data=journal and delalloc");
5015                         err = -EINVAL;
5016                         goto restore_opts;
5017                 }
5018                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5019                         ext4_msg(sb, KERN_ERR, "can't mount with "
5020                                  "both data=journal and dioread_nolock");
5021                         err = -EINVAL;
5022                         goto restore_opts;
5023                 }
5024                 if (test_opt(sb, DAX)) {
5025                         ext4_msg(sb, KERN_ERR, "can't mount with "
5026                                  "both data=journal and dax");
5027                         err = -EINVAL;
5028                         goto restore_opts;
5029                 }
5030         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5031                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5032                         ext4_msg(sb, KERN_ERR, "can't mount with "
5033                                 "journal_async_commit in data=ordered mode");
5034                         err = -EINVAL;
5035                         goto restore_opts;
5036                 }
5037         }
5038
5039         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5040                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5041                 err = -EINVAL;
5042                 goto restore_opts;
5043         }
5044
5045         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5046                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5047                         "dax flag with busy inodes while remounting");
5048                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5049         }
5050
5051         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5052                 ext4_abort(sb, "Abort forced by user");
5053
5054         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
5055                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
5056
5057         es = sbi->s_es;
5058
5059         if (sbi->s_journal) {
5060                 ext4_init_journal_params(sb, sbi->s_journal);
5061                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5062         }
5063
5064         if (*flags & MS_LAZYTIME)
5065                 sb->s_flags |= MS_LAZYTIME;
5066
5067         if ((bool)(*flags & MS_RDONLY) != sb_rdonly(sb)) {
5068                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5069                         err = -EROFS;
5070                         goto restore_opts;
5071                 }
5072
5073                 if (*flags & MS_RDONLY) {
5074                         err = sync_filesystem(sb);
5075                         if (err < 0)
5076                                 goto restore_opts;
5077                         err = dquot_suspend(sb, -1);
5078                         if (err < 0)
5079                                 goto restore_opts;
5080
5081                         /*
5082                          * First of all, the unconditional stuff we have to do
5083                          * to disable replay of the journal when we next remount
5084                          */
5085                         sb->s_flags |= MS_RDONLY;
5086
5087                         /*
5088                          * OK, test if we are remounting a valid rw partition
5089                          * readonly, and if so set the rdonly flag and then
5090                          * mark the partition as valid again.
5091                          */
5092                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5093                             (sbi->s_mount_state & EXT4_VALID_FS))
5094                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5095
5096                         if (sbi->s_journal)
5097                                 ext4_mark_recovery_complete(sb, es);
5098                 } else {
5099                         /* Make sure we can mount this feature set readwrite */
5100                         if (ext4_has_feature_readonly(sb) ||
5101                             !ext4_feature_set_ok(sb, 0)) {
5102                                 err = -EROFS;
5103                                 goto restore_opts;
5104                         }
5105                         /*
5106                          * Make sure the group descriptor checksums
5107                          * are sane.  If they aren't, refuse to remount r/w.
5108                          */
5109                         for (g = 0; g < sbi->s_groups_count; g++) {
5110                                 struct ext4_group_desc *gdp =
5111                                         ext4_get_group_desc(sb, g, NULL);
5112
5113                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5114                                         ext4_msg(sb, KERN_ERR,
5115                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5116                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5117                                                le16_to_cpu(gdp->bg_checksum));
5118                                         err = -EFSBADCRC;
5119                                         goto restore_opts;
5120                                 }
5121                         }
5122
5123                         /*
5124                          * If we have an unprocessed orphan list hanging
5125                          * around from a previously readonly bdev mount,
5126                          * require a full umount/remount for now.
5127                          */
5128                         if (es->s_last_orphan) {
5129                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5130                                        "remount RDWR because of unprocessed "
5131                                        "orphan inode list.  Please "
5132                                        "umount/remount instead");
5133                                 err = -EINVAL;
5134                                 goto restore_opts;
5135                         }
5136
5137                         /*
5138                          * Mounting a RDONLY partition read-write, so reread
5139                          * and store the current valid flag.  (It may have
5140                          * been changed by e2fsck since we originally mounted
5141                          * the partition.)
5142                          */
5143                         if (sbi->s_journal)
5144                                 ext4_clear_journal_err(sb, es);
5145                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5146                         if (!ext4_setup_super(sb, es, 0))
5147                                 sb->s_flags &= ~MS_RDONLY;
5148                         if (ext4_has_feature_mmp(sb))
5149                                 if (ext4_multi_mount_protect(sb,
5150                                                 le64_to_cpu(es->s_mmp_block))) {
5151                                         err = -EROFS;
5152                                         goto restore_opts;
5153                                 }
5154                         enable_quota = 1;
5155                 }
5156         }
5157
5158         /*
5159          * Reinitialize lazy itable initialization thread based on
5160          * current settings
5161          */
5162         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5163                 ext4_unregister_li_request(sb);
5164         else {
5165                 ext4_group_t first_not_zeroed;
5166                 first_not_zeroed = ext4_has_uninit_itable(sb);
5167                 ext4_register_li_request(sb, first_not_zeroed);
5168         }
5169
5170         ext4_setup_system_zone(sb);
5171         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
5172                 ext4_commit_super(sb, 1);
5173
5174 #ifdef CONFIG_QUOTA
5175         /* Release old quota file names */
5176         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5177                 kfree(old_opts.s_qf_names[i]);
5178         if (enable_quota) {
5179                 if (sb_any_quota_suspended(sb))
5180                         dquot_resume(sb, -1);
5181                 else if (ext4_has_feature_quota(sb)) {
5182                         err = ext4_enable_quotas(sb);
5183                         if (err)
5184                                 goto restore_opts;
5185                 }
5186         }
5187 #endif
5188
5189         *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
5190         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5191         kfree(orig_data);
5192         return 0;
5193
5194 restore_opts:
5195         sb->s_flags = old_sb_flags;
5196         sbi->s_mount_opt = old_opts.s_mount_opt;
5197         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5198         sbi->s_resuid = old_opts.s_resuid;
5199         sbi->s_resgid = old_opts.s_resgid;
5200         sbi->s_commit_interval = old_opts.s_commit_interval;
5201         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5202         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5203 #ifdef CONFIG_QUOTA
5204         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5205         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5206                 kfree(sbi->s_qf_names[i]);
5207                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5208         }
5209 #endif
5210         kfree(orig_data);
5211         return err;
5212 }
5213
5214 #ifdef CONFIG_QUOTA
5215 static int ext4_statfs_project(struct super_block *sb,
5216                                kprojid_t projid, struct kstatfs *buf)
5217 {
5218         struct kqid qid;
5219         struct dquot *dquot;
5220         u64 limit;
5221         u64 curblock;
5222
5223         qid = make_kqid_projid(projid);
5224         dquot = dqget(sb, qid);
5225         if (IS_ERR(dquot))
5226                 return PTR_ERR(dquot);
5227         spin_lock(&dquot->dq_dqb_lock);
5228
5229         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5230                  dquot->dq_dqb.dqb_bsoftlimit :
5231                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5232         if (limit && buf->f_blocks > limit) {
5233                 curblock = dquot->dq_dqb.dqb_curspace >> sb->s_blocksize_bits;
5234                 buf->f_blocks = limit;
5235                 buf->f_bfree = buf->f_bavail =
5236                         (buf->f_blocks > curblock) ?
5237                          (buf->f_blocks - curblock) : 0;
5238         }
5239
5240         limit = dquot->dq_dqb.dqb_isoftlimit ?
5241                 dquot->dq_dqb.dqb_isoftlimit :
5242                 dquot->dq_dqb.dqb_ihardlimit;
5243         if (limit && buf->f_files > limit) {
5244                 buf->f_files = limit;
5245                 buf->f_ffree =
5246                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5247                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5248         }
5249
5250         spin_unlock(&dquot->dq_dqb_lock);
5251         dqput(dquot);
5252         return 0;
5253 }
5254 #endif
5255
5256 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5257 {
5258         struct super_block *sb = dentry->d_sb;
5259         struct ext4_sb_info *sbi = EXT4_SB(sb);
5260         struct ext4_super_block *es = sbi->s_es;
5261         ext4_fsblk_t overhead = 0, resv_blocks;
5262         u64 fsid;
5263         s64 bfree;
5264         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5265
5266         if (!test_opt(sb, MINIX_DF))
5267                 overhead = sbi->s_overhead;
5268
5269         buf->f_type = EXT4_SUPER_MAGIC;
5270         buf->f_bsize = sb->s_blocksize;
5271         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5272         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5273                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5274         /* prevent underflow in case that few free space is available */
5275         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5276         buf->f_bavail = buf->f_bfree -
5277                         (ext4_r_blocks_count(es) + resv_blocks);
5278         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5279                 buf->f_bavail = 0;
5280         buf->f_files = le32_to_cpu(es->s_inodes_count);
5281         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5282         buf->f_namelen = EXT4_NAME_LEN;
5283         fsid = le64_to_cpup((void *)es->s_uuid) ^
5284                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5285         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5286         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5287
5288 #ifdef CONFIG_QUOTA
5289         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5290             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5291                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5292 #endif
5293         return 0;
5294 }
5295
5296
5297 #ifdef CONFIG_QUOTA
5298
5299 /*
5300  * Helper functions so that transaction is started before we acquire dqio_sem
5301  * to keep correct lock ordering of transaction > dqio_sem
5302  */
5303 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5304 {
5305         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5306 }
5307
5308 static int ext4_write_dquot(struct dquot *dquot)
5309 {
5310         int ret, err;
5311         handle_t *handle;
5312         struct inode *inode;
5313
5314         inode = dquot_to_inode(dquot);
5315         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5316                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5317         if (IS_ERR(handle))
5318                 return PTR_ERR(handle);
5319         ret = dquot_commit(dquot);
5320         err = ext4_journal_stop(handle);
5321         if (!ret)
5322                 ret = err;
5323         return ret;
5324 }
5325
5326 static int ext4_acquire_dquot(struct dquot *dquot)
5327 {
5328         int ret, err;
5329         handle_t *handle;
5330
5331         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5332                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5333         if (IS_ERR(handle))
5334                 return PTR_ERR(handle);
5335         ret = dquot_acquire(dquot);
5336         err = ext4_journal_stop(handle);
5337         if (!ret)
5338                 ret = err;
5339         return ret;
5340 }
5341
5342 static int ext4_release_dquot(struct dquot *dquot)
5343 {
5344         int ret, err;
5345         handle_t *handle;
5346
5347         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5348                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5349         if (IS_ERR(handle)) {
5350                 /* Release dquot anyway to avoid endless cycle in dqput() */
5351                 dquot_release(dquot);
5352                 return PTR_ERR(handle);
5353         }
5354         ret = dquot_release(dquot);
5355         err = ext4_journal_stop(handle);
5356         if (!ret)
5357                 ret = err;
5358         return ret;
5359 }
5360
5361 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5362 {
5363         struct super_block *sb = dquot->dq_sb;
5364         struct ext4_sb_info *sbi = EXT4_SB(sb);
5365
5366         /* Are we journaling quotas? */
5367         if (ext4_has_feature_quota(sb) ||
5368             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5369                 dquot_mark_dquot_dirty(dquot);
5370                 return ext4_write_dquot(dquot);
5371         } else {
5372                 return dquot_mark_dquot_dirty(dquot);
5373         }
5374 }
5375
5376 static int ext4_write_info(struct super_block *sb, int type)
5377 {
5378         int ret, err;
5379         handle_t *handle;
5380
5381         /* Data block + inode block */
5382         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5383         if (IS_ERR(handle))
5384                 return PTR_ERR(handle);
5385         ret = dquot_commit_info(sb, type);
5386         err = ext4_journal_stop(handle);
5387         if (!ret)
5388                 ret = err;
5389         return ret;
5390 }
5391
5392 /*
5393  * Turn on quotas during mount time - we need to find
5394  * the quota file and such...
5395  */
5396 static int ext4_quota_on_mount(struct super_block *sb, int type)
5397 {
5398         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5399                                         EXT4_SB(sb)->s_jquota_fmt, type);
5400 }
5401
5402 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5403 {
5404         struct ext4_inode_info *ei = EXT4_I(inode);
5405
5406         /* The first argument of lockdep_set_subclass has to be
5407          * *exactly* the same as the argument to init_rwsem() --- in
5408          * this case, in init_once() --- or lockdep gets unhappy
5409          * because the name of the lock is set using the
5410          * stringification of the argument to init_rwsem().
5411          */
5412         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5413         lockdep_set_subclass(&ei->i_data_sem, subclass);
5414 }
5415
5416 /*
5417  * Standard function to be called on quota_on
5418  */
5419 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5420                          const struct path *path)
5421 {
5422         int err;
5423
5424         if (!test_opt(sb, QUOTA))
5425                 return -EINVAL;
5426
5427         /* Quotafile not on the same filesystem? */
5428         if (path->dentry->d_sb != sb)
5429                 return -EXDEV;
5430         /* Journaling quota? */
5431         if (EXT4_SB(sb)->s_qf_names[type]) {
5432                 /* Quotafile not in fs root? */
5433                 if (path->dentry->d_parent != sb->s_root)
5434                         ext4_msg(sb, KERN_WARNING,
5435                                 "Quota file not on filesystem root. "
5436                                 "Journaled quota will not work");
5437                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5438         } else {
5439                 /*
5440                  * Clear the flag just in case mount options changed since
5441                  * last time.
5442                  */
5443                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5444         }
5445
5446         /*
5447          * When we journal data on quota file, we have to flush journal to see
5448          * all updates to the file when we bypass pagecache...
5449          */
5450         if (EXT4_SB(sb)->s_journal &&
5451             ext4_should_journal_data(d_inode(path->dentry))) {
5452                 /*
5453                  * We don't need to lock updates but journal_flush() could
5454                  * otherwise be livelocked...
5455                  */
5456                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5457                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5458                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5459                 if (err)
5460                         return err;
5461         }
5462
5463         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5464         err = dquot_quota_on(sb, type, format_id, path);
5465         if (err) {
5466                 lockdep_set_quota_inode(path->dentry->d_inode,
5467                                              I_DATA_SEM_NORMAL);
5468         } else {
5469                 struct inode *inode = d_inode(path->dentry);
5470                 handle_t *handle;
5471
5472                 /*
5473                  * Set inode flags to prevent userspace from messing with quota
5474                  * files. If this fails, we return success anyway since quotas
5475                  * are already enabled and this is not a hard failure.
5476                  */
5477                 inode_lock(inode);
5478                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5479                 if (IS_ERR(handle))
5480                         goto unlock_inode;
5481                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5482                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5483                                 S_NOATIME | S_IMMUTABLE);
5484                 ext4_mark_inode_dirty(handle, inode);
5485                 ext4_journal_stop(handle);
5486         unlock_inode:
5487                 inode_unlock(inode);
5488         }
5489         return err;
5490 }
5491
5492 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5493                              unsigned int flags)
5494 {
5495         int err;
5496         struct inode *qf_inode;
5497         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5498                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5499                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5500                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5501         };
5502
5503         BUG_ON(!ext4_has_feature_quota(sb));
5504
5505         if (!qf_inums[type])
5506                 return -EPERM;
5507
5508         qf_inode = ext4_iget(sb, qf_inums[type]);
5509         if (IS_ERR(qf_inode)) {
5510                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5511                 return PTR_ERR(qf_inode);
5512         }
5513
5514         /* Don't account quota for quota files to avoid recursion */
5515         qf_inode->i_flags |= S_NOQUOTA;
5516         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5517         err = dquot_enable(qf_inode, type, format_id, flags);
5518         iput(qf_inode);
5519         if (err)
5520                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5521
5522         return err;
5523 }
5524
5525 /* Enable usage tracking for all quota types. */
5526 static int ext4_enable_quotas(struct super_block *sb)
5527 {
5528         int type, err = 0;
5529         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5530                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5531                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5532                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5533         };
5534         bool quota_mopt[EXT4_MAXQUOTAS] = {
5535                 test_opt(sb, USRQUOTA),
5536                 test_opt(sb, GRPQUOTA),
5537                 test_opt(sb, PRJQUOTA),
5538         };
5539
5540         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5541         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5542                 if (qf_inums[type]) {
5543                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5544                                 DQUOT_USAGE_ENABLED |
5545                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5546                         if (err) {
5547                                 for (type--; type >= 0; type--)
5548                                         dquot_quota_off(sb, type);
5549
5550                                 ext4_warning(sb,
5551                                         "Failed to enable quota tracking "
5552                                         "(type=%d, err=%d). Please run "
5553                                         "e2fsck to fix.", type, err);
5554                                 return err;
5555                         }
5556                 }
5557         }
5558         return 0;
5559 }
5560
5561 static int ext4_quota_off(struct super_block *sb, int type)
5562 {
5563         struct inode *inode = sb_dqopt(sb)->files[type];
5564         handle_t *handle;
5565         int err;
5566
5567         /* Force all delayed allocation blocks to be allocated.
5568          * Caller already holds s_umount sem */
5569         if (test_opt(sb, DELALLOC))
5570                 sync_filesystem(sb);
5571
5572         if (!inode || !igrab(inode))
5573                 goto out;
5574
5575         err = dquot_quota_off(sb, type);
5576         if (err || ext4_has_feature_quota(sb))
5577                 goto out_put;
5578
5579         inode_lock(inode);
5580         /*
5581          * Update modification times of quota files when userspace can
5582          * start looking at them. If we fail, we return success anyway since
5583          * this is not a hard failure and quotas are already disabled.
5584          */
5585         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5586         if (IS_ERR(handle))
5587                 goto out_unlock;
5588         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5589         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5590         inode->i_mtime = inode->i_ctime = current_time(inode);
5591         ext4_mark_inode_dirty(handle, inode);
5592         ext4_journal_stop(handle);
5593 out_unlock:
5594         inode_unlock(inode);
5595 out_put:
5596         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5597         iput(inode);
5598         return err;
5599 out:
5600         return dquot_quota_off(sb, type);
5601 }
5602
5603 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5604  * acquiring the locks... As quota files are never truncated and quota code
5605  * itself serializes the operations (and no one else should touch the files)
5606  * we don't have to be afraid of races */
5607 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5608                                size_t len, loff_t off)
5609 {
5610         struct inode *inode = sb_dqopt(sb)->files[type];
5611         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5612         int offset = off & (sb->s_blocksize - 1);
5613         int tocopy;
5614         size_t toread;
5615         struct buffer_head *bh;
5616         loff_t i_size = i_size_read(inode);
5617
5618         if (off > i_size)
5619                 return 0;
5620         if (off+len > i_size)
5621                 len = i_size-off;
5622         toread = len;
5623         while (toread > 0) {
5624                 tocopy = sb->s_blocksize - offset < toread ?
5625                                 sb->s_blocksize - offset : toread;
5626                 bh = ext4_bread(NULL, inode, blk, 0);
5627                 if (IS_ERR(bh))
5628                         return PTR_ERR(bh);
5629                 if (!bh)        /* A hole? */
5630                         memset(data, 0, tocopy);
5631                 else
5632                         memcpy(data, bh->b_data+offset, tocopy);
5633                 brelse(bh);
5634                 offset = 0;
5635                 toread -= tocopy;
5636                 data += tocopy;
5637                 blk++;
5638         }
5639         return len;
5640 }
5641
5642 /* Write to quotafile (we know the transaction is already started and has
5643  * enough credits) */
5644 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5645                                 const char *data, size_t len, loff_t off)
5646 {
5647         struct inode *inode = sb_dqopt(sb)->files[type];
5648         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5649         int err, offset = off & (sb->s_blocksize - 1);
5650         int retries = 0;
5651         struct buffer_head *bh;
5652         handle_t *handle = journal_current_handle();
5653
5654         if (EXT4_SB(sb)->s_journal && !handle) {
5655                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5656                         " cancelled because transaction is not started",
5657                         (unsigned long long)off, (unsigned long long)len);
5658                 return -EIO;
5659         }
5660         /*
5661          * Since we account only one data block in transaction credits,
5662          * then it is impossible to cross a block boundary.
5663          */
5664         if (sb->s_blocksize - offset < len) {
5665                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5666                         " cancelled because not block aligned",
5667                         (unsigned long long)off, (unsigned long long)len);
5668                 return -EIO;
5669         }
5670
5671         do {
5672                 bh = ext4_bread(handle, inode, blk,
5673                                 EXT4_GET_BLOCKS_CREATE |
5674                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5675         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5676                  ext4_should_retry_alloc(inode->i_sb, &retries));
5677         if (IS_ERR(bh))
5678                 return PTR_ERR(bh);
5679         if (!bh)
5680                 goto out;
5681         BUFFER_TRACE(bh, "get write access");
5682         err = ext4_journal_get_write_access(handle, bh);
5683         if (err) {
5684                 brelse(bh);
5685                 return err;
5686         }
5687         lock_buffer(bh);
5688         memcpy(bh->b_data+offset, data, len);
5689         flush_dcache_page(bh->b_page);
5690         unlock_buffer(bh);
5691         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5692         brelse(bh);
5693 out:
5694         if (inode->i_size < off + len) {
5695                 i_size_write(inode, off + len);
5696                 EXT4_I(inode)->i_disksize = inode->i_size;
5697                 ext4_mark_inode_dirty(handle, inode);
5698         }
5699         return len;
5700 }
5701
5702 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
5703 {
5704         const struct quota_format_ops   *ops;
5705
5706         if (!sb_has_quota_loaded(sb, qid->type))
5707                 return -ESRCH;
5708         ops = sb_dqopt(sb)->ops[qid->type];
5709         if (!ops || !ops->get_next_id)
5710                 return -ENOSYS;
5711         return dquot_get_next_id(sb, qid);
5712 }
5713 #endif
5714
5715 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5716                        const char *dev_name, void *data)
5717 {
5718         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5719 }
5720
5721 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5722 static inline void register_as_ext2(void)
5723 {
5724         int err = register_filesystem(&ext2_fs_type);
5725         if (err)
5726                 printk(KERN_WARNING
5727                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5728 }
5729
5730 static inline void unregister_as_ext2(void)
5731 {
5732         unregister_filesystem(&ext2_fs_type);
5733 }
5734
5735 static inline int ext2_feature_set_ok(struct super_block *sb)
5736 {
5737         if (ext4_has_unknown_ext2_incompat_features(sb))
5738                 return 0;
5739         if (sb_rdonly(sb))
5740                 return 1;
5741         if (ext4_has_unknown_ext2_ro_compat_features(sb))
5742                 return 0;
5743         return 1;
5744 }
5745 #else
5746 static inline void register_as_ext2(void) { }
5747 static inline void unregister_as_ext2(void) { }
5748 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5749 #endif
5750
5751 static inline void register_as_ext3(void)
5752 {
5753         int err = register_filesystem(&ext3_fs_type);
5754         if (err)
5755                 printk(KERN_WARNING
5756                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5757 }
5758
5759 static inline void unregister_as_ext3(void)
5760 {
5761         unregister_filesystem(&ext3_fs_type);
5762 }
5763
5764 static inline int ext3_feature_set_ok(struct super_block *sb)
5765 {
5766         if (ext4_has_unknown_ext3_incompat_features(sb))
5767                 return 0;
5768         if (!ext4_has_feature_journal(sb))
5769                 return 0;
5770         if (sb_rdonly(sb))
5771                 return 1;
5772         if (ext4_has_unknown_ext3_ro_compat_features(sb))
5773                 return 0;
5774         return 1;
5775 }
5776
5777 static struct file_system_type ext4_fs_type = {
5778         .owner          = THIS_MODULE,
5779         .name           = "ext4",
5780         .mount          = ext4_mount,
5781         .kill_sb        = kill_block_super,
5782         .fs_flags       = FS_REQUIRES_DEV,
5783 };
5784 MODULE_ALIAS_FS("ext4");
5785
5786 /* Shared across all ext4 file systems */
5787 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5788
5789 static int __init ext4_init_fs(void)
5790 {
5791         int i, err;
5792
5793         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
5794         ext4_li_info = NULL;
5795         mutex_init(&ext4_li_mtx);
5796
5797         /* Build-time check for flags consistency */
5798         ext4_check_flag_values();
5799
5800         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
5801                 init_waitqueue_head(&ext4__ioend_wq[i]);
5802
5803         err = ext4_init_es();
5804         if (err)
5805                 return err;
5806
5807         err = ext4_init_pageio();
5808         if (err)
5809                 goto out5;
5810
5811         err = ext4_init_system_zone();
5812         if (err)
5813                 goto out4;
5814
5815         err = ext4_init_sysfs();
5816         if (err)
5817                 goto out3;
5818
5819         err = ext4_init_mballoc();
5820         if (err)
5821                 goto out2;
5822         err = init_inodecache();
5823         if (err)
5824                 goto out1;
5825         register_as_ext3();
5826         register_as_ext2();
5827         err = register_filesystem(&ext4_fs_type);
5828         if (err)
5829                 goto out;
5830
5831         return 0;
5832 out:
5833         unregister_as_ext2();
5834         unregister_as_ext3();
5835         destroy_inodecache();
5836 out1:
5837         ext4_exit_mballoc();
5838 out2:
5839         ext4_exit_sysfs();
5840 out3:
5841         ext4_exit_system_zone();
5842 out4:
5843         ext4_exit_pageio();
5844 out5:
5845         ext4_exit_es();
5846
5847         return err;
5848 }
5849
5850 static void __exit ext4_exit_fs(void)
5851 {
5852         ext4_destroy_lazyinit_thread();
5853         unregister_as_ext2();
5854         unregister_as_ext3();
5855         unregister_filesystem(&ext4_fs_type);
5856         destroy_inodecache();
5857         ext4_exit_mballoc();
5858         ext4_exit_sysfs();
5859         ext4_exit_system_zone();
5860         ext4_exit_pageio();
5861         ext4_exit_es();
5862 }
5863
5864 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5865 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5866 MODULE_LICENSE("GPL");
5867 module_init(ext4_init_fs)
5868 module_exit(ext4_exit_fs)