1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/fs/minix/inode.c
5 * Copyright (C) 1991, 1992 Linus Torvalds
7 * Copyright (C) 1996 Gertjan van Wingerde
10 * Modified for 680x0 by Andreas Schwab
11 * Updated to filesystem version 3 by Daniel Aragones
14 #include <linux/module.h>
16 #include <linux/buffer_head.h>
17 #include <linux/slab.h>
18 #include <linux/init.h>
19 #include <linux/highuid.h>
20 #include <linux/vfs.h>
21 #include <linux/writeback.h>
23 static int minix_write_inode(struct inode *inode,
24 struct writeback_control *wbc);
25 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
26 static int minix_remount (struct super_block * sb, int * flags, char * data);
28 static void minix_evict_inode(struct inode *inode)
30 truncate_inode_pages_final(&inode->i_data);
31 if (!inode->i_nlink) {
33 minix_truncate(inode);
35 invalidate_inode_buffers(inode);
38 minix_free_inode(inode);
41 static void minix_put_super(struct super_block *sb)
44 struct minix_sb_info *sbi = minix_sb(sb);
47 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
48 sbi->s_ms->s_state = sbi->s_mount_state;
49 mark_buffer_dirty(sbi->s_sbh);
51 for (i = 0; i < sbi->s_imap_blocks; i++)
52 brelse(sbi->s_imap[i]);
53 for (i = 0; i < sbi->s_zmap_blocks; i++)
54 brelse(sbi->s_zmap[i]);
61 static struct kmem_cache * minix_inode_cachep;
63 static struct inode *minix_alloc_inode(struct super_block *sb)
65 struct minix_inode_info *ei;
66 ei = kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
69 return &ei->vfs_inode;
72 static void minix_free_in_core_inode(struct inode *inode)
74 kmem_cache_free(minix_inode_cachep, minix_i(inode));
77 static void init_once(void *foo)
79 struct minix_inode_info *ei = (struct minix_inode_info *) foo;
81 inode_init_once(&ei->vfs_inode);
84 static int __init init_inodecache(void)
86 minix_inode_cachep = kmem_cache_create("minix_inode_cache",
87 sizeof(struct minix_inode_info),
88 0, (SLAB_RECLAIM_ACCOUNT|
89 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
91 if (minix_inode_cachep == NULL)
96 static void destroy_inodecache(void)
99 * Make sure all delayed rcu free inodes are flushed before we
103 kmem_cache_destroy(minix_inode_cachep);
106 static const struct super_operations minix_sops = {
107 .alloc_inode = minix_alloc_inode,
108 .free_inode = minix_free_in_core_inode,
109 .write_inode = minix_write_inode,
110 .evict_inode = minix_evict_inode,
111 .put_super = minix_put_super,
112 .statfs = minix_statfs,
113 .remount_fs = minix_remount,
116 static int minix_remount (struct super_block * sb, int * flags, char * data)
118 struct minix_sb_info * sbi = minix_sb(sb);
119 struct minix_super_block * ms;
123 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
125 if (*flags & SB_RDONLY) {
126 if (ms->s_state & MINIX_VALID_FS ||
127 !(sbi->s_mount_state & MINIX_VALID_FS))
129 /* Mounting a rw partition read-only. */
130 if (sbi->s_version != MINIX_V3)
131 ms->s_state = sbi->s_mount_state;
132 mark_buffer_dirty(sbi->s_sbh);
134 /* Mount a partition which is read-only, read-write. */
135 if (sbi->s_version != MINIX_V3) {
136 sbi->s_mount_state = ms->s_state;
137 ms->s_state &= ~MINIX_VALID_FS;
139 sbi->s_mount_state = MINIX_VALID_FS;
141 mark_buffer_dirty(sbi->s_sbh);
143 if (!(sbi->s_mount_state & MINIX_VALID_FS))
144 printk("MINIX-fs warning: remounting unchecked fs, "
145 "running fsck is recommended\n");
146 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
147 printk("MINIX-fs warning: remounting fs with errors, "
148 "running fsck is recommended\n");
153 static int minix_fill_super(struct super_block *s, void *data, int silent)
155 struct buffer_head *bh;
156 struct buffer_head **map;
157 struct minix_super_block *ms;
158 struct minix3_super_block *m3s = NULL;
159 unsigned long i, block;
160 struct inode *root_inode;
161 struct minix_sb_info *sbi;
164 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
169 BUILD_BUG_ON(32 != sizeof (struct minix_inode));
170 BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
172 if (!sb_set_blocksize(s, BLOCK_SIZE))
175 if (!(bh = sb_bread(s, 1)))
178 ms = (struct minix_super_block *) bh->b_data;
181 sbi->s_mount_state = ms->s_state;
182 sbi->s_ninodes = ms->s_ninodes;
183 sbi->s_nzones = ms->s_nzones;
184 sbi->s_imap_blocks = ms->s_imap_blocks;
185 sbi->s_zmap_blocks = ms->s_zmap_blocks;
186 sbi->s_firstdatazone = ms->s_firstdatazone;
187 sbi->s_log_zone_size = ms->s_log_zone_size;
188 sbi->s_max_size = ms->s_max_size;
189 s->s_magic = ms->s_magic;
190 if (s->s_magic == MINIX_SUPER_MAGIC) {
191 sbi->s_version = MINIX_V1;
194 s->s_max_links = MINIX_LINK_MAX;
195 } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
196 sbi->s_version = MINIX_V1;
199 s->s_max_links = MINIX_LINK_MAX;
200 } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
201 sbi->s_version = MINIX_V2;
202 sbi->s_nzones = ms->s_zones;
205 s->s_max_links = MINIX2_LINK_MAX;
206 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
207 sbi->s_version = MINIX_V2;
208 sbi->s_nzones = ms->s_zones;
211 s->s_max_links = MINIX2_LINK_MAX;
212 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
213 m3s = (struct minix3_super_block *) bh->b_data;
214 s->s_magic = m3s->s_magic;
215 sbi->s_imap_blocks = m3s->s_imap_blocks;
216 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
217 sbi->s_firstdatazone = m3s->s_firstdatazone;
218 sbi->s_log_zone_size = m3s->s_log_zone_size;
219 sbi->s_max_size = m3s->s_max_size;
220 sbi->s_ninodes = m3s->s_ninodes;
221 sbi->s_nzones = m3s->s_zones;
224 sbi->s_version = MINIX_V3;
225 sbi->s_mount_state = MINIX_VALID_FS;
226 sb_set_blocksize(s, m3s->s_blocksize);
227 s->s_max_links = MINIX2_LINK_MAX;
232 * Allocate the buffer map to keep the superblock small.
234 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
236 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
237 map = kzalloc(i, GFP_KERNEL);
240 sbi->s_imap = &map[0];
241 sbi->s_zmap = &map[sbi->s_imap_blocks];
244 for (i=0 ; i < sbi->s_imap_blocks ; i++) {
245 if (!(sbi->s_imap[i]=sb_bread(s, block)))
249 for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
250 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
255 minix_set_bit(0,sbi->s_imap[0]->b_data);
256 minix_set_bit(0,sbi->s_zmap[0]->b_data);
258 /* Apparently minix can create filesystems that allocate more blocks for
259 * the bitmaps than needed. We simply ignore that, but verify it didn't
260 * create one with not enough blocks and bail out if so.
262 block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
263 if (sbi->s_imap_blocks < block) {
264 printk("MINIX-fs: file system does not have enough "
265 "imap blocks allocated. Refusing to mount.\n");
269 block = minix_blocks_needed(
270 (sbi->s_nzones - sbi->s_firstdatazone + 1),
272 if (sbi->s_zmap_blocks < block) {
273 printk("MINIX-fs: file system does not have enough "
274 "zmap blocks allocated. Refusing to mount.\n");
278 /* set up enough so that it can read an inode */
279 s->s_op = &minix_sops;
280 root_inode = minix_iget(s, MINIX_ROOT_INO);
281 if (IS_ERR(root_inode)) {
282 ret = PTR_ERR(root_inode);
287 s->s_root = d_make_root(root_inode);
292 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
293 ms->s_state &= ~MINIX_VALID_FS;
294 mark_buffer_dirty(bh);
296 if (!(sbi->s_mount_state & MINIX_VALID_FS))
297 printk("MINIX-fs: mounting unchecked file system, "
298 "running fsck is recommended\n");
299 else if (sbi->s_mount_state & MINIX_ERROR_FS)
300 printk("MINIX-fs: mounting file system with errors, "
301 "running fsck is recommended\n");
307 printk("MINIX-fs: get root inode failed\n");
311 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
313 for (i = 0; i < sbi->s_imap_blocks; i++)
314 brelse(sbi->s_imap[i]);
315 for (i = 0; i < sbi->s_zmap_blocks; i++)
316 brelse(sbi->s_zmap[i]);
323 printk("MINIX-fs: can't allocate map\n");
328 printk("MINIX-fs: bad superblock\n");
333 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
334 "on device %s.\n", s->s_id);
340 printk("MINIX-fs: blocksize too small for device\n");
344 printk("MINIX-fs: unable to read superblock\n");
351 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
353 struct super_block *sb = dentry->d_sb;
354 struct minix_sb_info *sbi = minix_sb(sb);
355 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
356 buf->f_type = sb->s_magic;
357 buf->f_bsize = sb->s_blocksize;
358 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
359 buf->f_bfree = minix_count_free_blocks(sb);
360 buf->f_bavail = buf->f_bfree;
361 buf->f_files = sbi->s_ninodes;
362 buf->f_ffree = minix_count_free_inodes(sb);
363 buf->f_namelen = sbi->s_namelen;
364 buf->f_fsid.val[0] = (u32)id;
365 buf->f_fsid.val[1] = (u32)(id >> 32);
370 static int minix_get_block(struct inode *inode, sector_t block,
371 struct buffer_head *bh_result, int create)
373 if (INODE_VERSION(inode) == MINIX_V1)
374 return V1_minix_get_block(inode, block, bh_result, create);
376 return V2_minix_get_block(inode, block, bh_result, create);
379 static int minix_writepage(struct page *page, struct writeback_control *wbc)
381 return block_write_full_page(page, minix_get_block, wbc);
384 static int minix_readpage(struct file *file, struct page *page)
386 return block_read_full_page(page,minix_get_block);
389 int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
391 return __block_write_begin(page, pos, len, minix_get_block);
394 static void minix_write_failed(struct address_space *mapping, loff_t to)
396 struct inode *inode = mapping->host;
398 if (to > inode->i_size) {
399 truncate_pagecache(inode, inode->i_size);
400 minix_truncate(inode);
404 static int minix_write_begin(struct file *file, struct address_space *mapping,
405 loff_t pos, unsigned len, unsigned flags,
406 struct page **pagep, void **fsdata)
410 ret = block_write_begin(mapping, pos, len, flags, pagep,
413 minix_write_failed(mapping, pos + len);
418 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
420 return generic_block_bmap(mapping,block,minix_get_block);
423 static const struct address_space_operations minix_aops = {
424 .readpage = minix_readpage,
425 .writepage = minix_writepage,
426 .write_begin = minix_write_begin,
427 .write_end = generic_write_end,
431 static const struct inode_operations minix_symlink_inode_operations = {
432 .get_link = page_get_link,
433 .getattr = minix_getattr,
436 void minix_set_inode(struct inode *inode, dev_t rdev)
438 if (S_ISREG(inode->i_mode)) {
439 inode->i_op = &minix_file_inode_operations;
440 inode->i_fop = &minix_file_operations;
441 inode->i_mapping->a_ops = &minix_aops;
442 } else if (S_ISDIR(inode->i_mode)) {
443 inode->i_op = &minix_dir_inode_operations;
444 inode->i_fop = &minix_dir_operations;
445 inode->i_mapping->a_ops = &minix_aops;
446 } else if (S_ISLNK(inode->i_mode)) {
447 inode->i_op = &minix_symlink_inode_operations;
448 inode_nohighmem(inode);
449 inode->i_mapping->a_ops = &minix_aops;
451 init_special_inode(inode, inode->i_mode, rdev);
455 * The minix V1 function to read an inode.
457 static struct inode *V1_minix_iget(struct inode *inode)
459 struct buffer_head * bh;
460 struct minix_inode * raw_inode;
461 struct minix_inode_info *minix_inode = minix_i(inode);
464 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
467 return ERR_PTR(-EIO);
469 inode->i_mode = raw_inode->i_mode;
470 i_uid_write(inode, raw_inode->i_uid);
471 i_gid_write(inode, raw_inode->i_gid);
472 set_nlink(inode, raw_inode->i_nlinks);
473 inode->i_size = raw_inode->i_size;
474 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
475 inode->i_mtime.tv_nsec = 0;
476 inode->i_atime.tv_nsec = 0;
477 inode->i_ctime.tv_nsec = 0;
479 for (i = 0; i < 9; i++)
480 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
481 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
483 unlock_new_inode(inode);
488 * The minix V2 function to read an inode.
490 static struct inode *V2_minix_iget(struct inode *inode)
492 struct buffer_head * bh;
493 struct minix2_inode * raw_inode;
494 struct minix_inode_info *minix_inode = minix_i(inode);
497 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
500 return ERR_PTR(-EIO);
502 inode->i_mode = raw_inode->i_mode;
503 i_uid_write(inode, raw_inode->i_uid);
504 i_gid_write(inode, raw_inode->i_gid);
505 set_nlink(inode, raw_inode->i_nlinks);
506 inode->i_size = raw_inode->i_size;
507 inode->i_mtime.tv_sec = raw_inode->i_mtime;
508 inode->i_atime.tv_sec = raw_inode->i_atime;
509 inode->i_ctime.tv_sec = raw_inode->i_ctime;
510 inode->i_mtime.tv_nsec = 0;
511 inode->i_atime.tv_nsec = 0;
512 inode->i_ctime.tv_nsec = 0;
514 for (i = 0; i < 10; i++)
515 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
516 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
518 unlock_new_inode(inode);
523 * The global function to read an inode.
525 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
529 inode = iget_locked(sb, ino);
531 return ERR_PTR(-ENOMEM);
532 if (!(inode->i_state & I_NEW))
535 if (INODE_VERSION(inode) == MINIX_V1)
536 return V1_minix_iget(inode);
538 return V2_minix_iget(inode);
542 * The minix V1 function to synchronize an inode.
544 static struct buffer_head * V1_minix_update_inode(struct inode * inode)
546 struct buffer_head * bh;
547 struct minix_inode * raw_inode;
548 struct minix_inode_info *minix_inode = minix_i(inode);
551 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
554 raw_inode->i_mode = inode->i_mode;
555 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
556 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
557 raw_inode->i_nlinks = inode->i_nlink;
558 raw_inode->i_size = inode->i_size;
559 raw_inode->i_time = inode->i_mtime.tv_sec;
560 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
561 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
562 else for (i = 0; i < 9; i++)
563 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
564 mark_buffer_dirty(bh);
569 * The minix V2 function to synchronize an inode.
571 static struct buffer_head * V2_minix_update_inode(struct inode * inode)
573 struct buffer_head * bh;
574 struct minix2_inode * raw_inode;
575 struct minix_inode_info *minix_inode = minix_i(inode);
578 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
581 raw_inode->i_mode = inode->i_mode;
582 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
583 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
584 raw_inode->i_nlinks = inode->i_nlink;
585 raw_inode->i_size = inode->i_size;
586 raw_inode->i_mtime = inode->i_mtime.tv_sec;
587 raw_inode->i_atime = inode->i_atime.tv_sec;
588 raw_inode->i_ctime = inode->i_ctime.tv_sec;
589 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
590 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
591 else for (i = 0; i < 10; i++)
592 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
593 mark_buffer_dirty(bh);
597 static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
600 struct buffer_head *bh;
602 if (INODE_VERSION(inode) == MINIX_V1)
603 bh = V1_minix_update_inode(inode);
605 bh = V2_minix_update_inode(inode);
608 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
609 sync_dirty_buffer(bh);
610 if (buffer_req(bh) && !buffer_uptodate(bh)) {
611 printk("IO error syncing minix inode [%s:%08lx]\n",
612 inode->i_sb->s_id, inode->i_ino);
620 int minix_getattr(const struct path *path, struct kstat *stat,
621 u32 request_mask, unsigned int flags)
623 struct super_block *sb = path->dentry->d_sb;
624 struct inode *inode = d_inode(path->dentry);
626 generic_fillattr(inode, stat);
627 if (INODE_VERSION(inode) == MINIX_V1)
628 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
630 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
631 stat->blksize = sb->s_blocksize;
636 * The function that is called for file truncation.
638 void minix_truncate(struct inode * inode)
640 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
642 if (INODE_VERSION(inode) == MINIX_V1)
643 V1_minix_truncate(inode);
645 V2_minix_truncate(inode);
648 static struct dentry *minix_mount(struct file_system_type *fs_type,
649 int flags, const char *dev_name, void *data)
651 return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
654 static struct file_system_type minix_fs_type = {
655 .owner = THIS_MODULE,
657 .mount = minix_mount,
658 .kill_sb = kill_block_super,
659 .fs_flags = FS_REQUIRES_DEV,
661 MODULE_ALIAS_FS("minix");
663 static int __init init_minix_fs(void)
665 int err = init_inodecache();
668 err = register_filesystem(&minix_fs_type);
673 destroy_inodecache();
678 static void __exit exit_minix_fs(void)
680 unregister_filesystem(&minix_fs_type);
681 destroy_inodecache();
684 module_init(init_minix_fs)
685 module_exit(exit_minix_fs)
686 MODULE_LICENSE("GPL");