Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[wrt350n-kernel.git] / fs / minix / inode.c
blob84f6242ba6fc7262b2cf90a7d126f5192c6a13d9
1 /*
2 * linux/fs/minix/inode.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
6 * Copyright (C) 1996 Gertjan van Wingerde (gertjan@cs.vu.nl)
7 * Minix V2 fs support.
9 * Modified for 680x0 by Andreas Schwab
10 * Updated to filesystem version 3 by Daniel Aragones
13 #include <linux/module.h>
14 #include "minix.h"
15 #include <linux/buffer_head.h>
16 #include <linux/slab.h>
17 #include <linux/init.h>
18 #include <linux/highuid.h>
19 #include <linux/vfs.h>
21 static int minix_write_inode(struct inode * inode, int wait);
22 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
23 static int minix_remount (struct super_block * sb, int * flags, char * data);
25 static void minix_delete_inode(struct inode *inode)
27 truncate_inode_pages(&inode->i_data, 0);
28 inode->i_size = 0;
29 minix_truncate(inode);
30 minix_free_inode(inode);
33 static void minix_put_super(struct super_block *sb)
35 int i;
36 struct minix_sb_info *sbi = minix_sb(sb);
38 if (!(sb->s_flags & MS_RDONLY)) {
39 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
40 sbi->s_ms->s_state = sbi->s_mount_state;
41 mark_buffer_dirty(sbi->s_sbh);
43 for (i = 0; i < sbi->s_imap_blocks; i++)
44 brelse(sbi->s_imap[i]);
45 for (i = 0; i < sbi->s_zmap_blocks; i++)
46 brelse(sbi->s_zmap[i]);
47 brelse (sbi->s_sbh);
48 kfree(sbi->s_imap);
49 sb->s_fs_info = NULL;
50 kfree(sbi);
52 return;
55 static struct kmem_cache * minix_inode_cachep;
57 static struct inode *minix_alloc_inode(struct super_block *sb)
59 struct minix_inode_info *ei;
60 ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
61 if (!ei)
62 return NULL;
63 return &ei->vfs_inode;
66 static void minix_destroy_inode(struct inode *inode)
68 kmem_cache_free(minix_inode_cachep, minix_i(inode));
71 static void init_once(struct kmem_cache * cachep, void *foo)
73 struct minix_inode_info *ei = (struct minix_inode_info *) foo;
75 inode_init_once(&ei->vfs_inode);
78 static int init_inodecache(void)
80 minix_inode_cachep = kmem_cache_create("minix_inode_cache",
81 sizeof(struct minix_inode_info),
82 0, (SLAB_RECLAIM_ACCOUNT|
83 SLAB_MEM_SPREAD),
84 init_once);
85 if (minix_inode_cachep == NULL)
86 return -ENOMEM;
87 return 0;
90 static void destroy_inodecache(void)
92 kmem_cache_destroy(minix_inode_cachep);
95 static const struct super_operations minix_sops = {
96 .alloc_inode = minix_alloc_inode,
97 .destroy_inode = minix_destroy_inode,
98 .write_inode = minix_write_inode,
99 .delete_inode = minix_delete_inode,
100 .put_super = minix_put_super,
101 .statfs = minix_statfs,
102 .remount_fs = minix_remount,
105 static int minix_remount (struct super_block * sb, int * flags, char * data)
107 struct minix_sb_info * sbi = minix_sb(sb);
108 struct minix_super_block * ms;
110 ms = sbi->s_ms;
111 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
112 return 0;
113 if (*flags & MS_RDONLY) {
114 if (ms->s_state & MINIX_VALID_FS ||
115 !(sbi->s_mount_state & MINIX_VALID_FS))
116 return 0;
117 /* Mounting a rw partition read-only. */
118 if (sbi->s_version != MINIX_V3)
119 ms->s_state = sbi->s_mount_state;
120 mark_buffer_dirty(sbi->s_sbh);
121 } else {
122 /* Mount a partition which is read-only, read-write. */
123 if (sbi->s_version != MINIX_V3) {
124 sbi->s_mount_state = ms->s_state;
125 ms->s_state &= ~MINIX_VALID_FS;
126 } else {
127 sbi->s_mount_state = MINIX_VALID_FS;
129 mark_buffer_dirty(sbi->s_sbh);
131 if (!(sbi->s_mount_state & MINIX_VALID_FS))
132 printk("MINIX-fs warning: remounting unchecked fs, "
133 "running fsck is recommended\n");
134 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
135 printk("MINIX-fs warning: remounting fs with errors, "
136 "running fsck is recommended\n");
138 return 0;
141 static int minix_fill_super(struct super_block *s, void *data, int silent)
143 struct buffer_head *bh;
144 struct buffer_head **map;
145 struct minix_super_block *ms;
146 struct minix3_super_block *m3s = NULL;
147 unsigned long i, block;
148 struct inode *root_inode;
149 struct minix_sb_info *sbi;
150 int ret = -EINVAL;
152 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
153 if (!sbi)
154 return -ENOMEM;
155 s->s_fs_info = sbi;
157 BUILD_BUG_ON(32 != sizeof (struct minix_inode));
158 BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
160 if (!sb_set_blocksize(s, BLOCK_SIZE))
161 goto out_bad_hblock;
163 if (!(bh = sb_bread(s, 1)))
164 goto out_bad_sb;
166 ms = (struct minix_super_block *) bh->b_data;
167 sbi->s_ms = ms;
168 sbi->s_sbh = bh;
169 sbi->s_mount_state = ms->s_state;
170 sbi->s_ninodes = ms->s_ninodes;
171 sbi->s_nzones = ms->s_nzones;
172 sbi->s_imap_blocks = ms->s_imap_blocks;
173 sbi->s_zmap_blocks = ms->s_zmap_blocks;
174 sbi->s_firstdatazone = ms->s_firstdatazone;
175 sbi->s_log_zone_size = ms->s_log_zone_size;
176 sbi->s_max_size = ms->s_max_size;
177 s->s_magic = ms->s_magic;
178 if (s->s_magic == MINIX_SUPER_MAGIC) {
179 sbi->s_version = MINIX_V1;
180 sbi->s_dirsize = 16;
181 sbi->s_namelen = 14;
182 sbi->s_link_max = MINIX_LINK_MAX;
183 } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
184 sbi->s_version = MINIX_V1;
185 sbi->s_dirsize = 32;
186 sbi->s_namelen = 30;
187 sbi->s_link_max = MINIX_LINK_MAX;
188 } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
189 sbi->s_version = MINIX_V2;
190 sbi->s_nzones = ms->s_zones;
191 sbi->s_dirsize = 16;
192 sbi->s_namelen = 14;
193 sbi->s_link_max = MINIX2_LINK_MAX;
194 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
195 sbi->s_version = MINIX_V2;
196 sbi->s_nzones = ms->s_zones;
197 sbi->s_dirsize = 32;
198 sbi->s_namelen = 30;
199 sbi->s_link_max = MINIX2_LINK_MAX;
200 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
201 m3s = (struct minix3_super_block *) bh->b_data;
202 s->s_magic = m3s->s_magic;
203 sbi->s_imap_blocks = m3s->s_imap_blocks;
204 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
205 sbi->s_firstdatazone = m3s->s_firstdatazone;
206 sbi->s_log_zone_size = m3s->s_log_zone_size;
207 sbi->s_max_size = m3s->s_max_size;
208 sbi->s_ninodes = m3s->s_ninodes;
209 sbi->s_nzones = m3s->s_zones;
210 sbi->s_dirsize = 64;
211 sbi->s_namelen = 60;
212 sbi->s_version = MINIX_V3;
213 sbi->s_link_max = MINIX2_LINK_MAX;
214 sbi->s_mount_state = MINIX_VALID_FS;
215 sb_set_blocksize(s, m3s->s_blocksize);
216 } else
217 goto out_no_fs;
220 * Allocate the buffer map to keep the superblock small.
222 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
223 goto out_illegal_sb;
224 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
225 map = kzalloc(i, GFP_KERNEL);
226 if (!map)
227 goto out_no_map;
228 sbi->s_imap = &map[0];
229 sbi->s_zmap = &map[sbi->s_imap_blocks];
231 block=2;
232 for (i=0 ; i < sbi->s_imap_blocks ; i++) {
233 if (!(sbi->s_imap[i]=sb_bread(s, block)))
234 goto out_no_bitmap;
235 block++;
237 for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
238 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
239 goto out_no_bitmap;
240 block++;
243 minix_set_bit(0,sbi->s_imap[0]->b_data);
244 minix_set_bit(0,sbi->s_zmap[0]->b_data);
246 /* set up enough so that it can read an inode */
247 s->s_op = &minix_sops;
248 root_inode = minix_iget(s, MINIX_ROOT_INO);
249 if (IS_ERR(root_inode)) {
250 ret = PTR_ERR(root_inode);
251 goto out_no_root;
254 ret = -ENOMEM;
255 s->s_root = d_alloc_root(root_inode);
256 if (!s->s_root)
257 goto out_iput;
259 if (!NO_TRUNCATE)
260 s->s_root->d_op = &minix_dentry_operations;
262 if (!(s->s_flags & MS_RDONLY)) {
263 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
264 ms->s_state &= ~MINIX_VALID_FS;
265 mark_buffer_dirty(bh);
267 if (!(sbi->s_mount_state & MINIX_VALID_FS))
268 printk("MINIX-fs: mounting unchecked file system, "
269 "running fsck is recommended\n");
270 else if (sbi->s_mount_state & MINIX_ERROR_FS)
271 printk("MINIX-fs: mounting file system with errors, "
272 "running fsck is recommended\n");
273 return 0;
275 out_iput:
276 iput(root_inode);
277 goto out_freemap;
279 out_no_root:
280 if (!silent)
281 printk("MINIX-fs: get root inode failed\n");
282 goto out_freemap;
284 out_no_bitmap:
285 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
286 out_freemap:
287 for (i = 0; i < sbi->s_imap_blocks; i++)
288 brelse(sbi->s_imap[i]);
289 for (i = 0; i < sbi->s_zmap_blocks; i++)
290 brelse(sbi->s_zmap[i]);
291 kfree(sbi->s_imap);
292 goto out_release;
294 out_no_map:
295 ret = -ENOMEM;
296 if (!silent)
297 printk("MINIX-fs: can't allocate map\n");
298 goto out_release;
300 out_illegal_sb:
301 if (!silent)
302 printk("MINIX-fs: bad superblock\n");
303 goto out_release;
305 out_no_fs:
306 if (!silent)
307 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
308 "on device %s.\n", s->s_id);
309 out_release:
310 brelse(bh);
311 goto out;
313 out_bad_hblock:
314 printk("MINIX-fs: blocksize too small for device\n");
315 goto out;
317 out_bad_sb:
318 printk("MINIX-fs: unable to read superblock\n");
319 out:
320 s->s_fs_info = NULL;
321 kfree(sbi);
322 return ret;
325 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
327 struct minix_sb_info *sbi = minix_sb(dentry->d_sb);
328 buf->f_type = dentry->d_sb->s_magic;
329 buf->f_bsize = dentry->d_sb->s_blocksize;
330 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
331 buf->f_bfree = minix_count_free_blocks(sbi);
332 buf->f_bavail = buf->f_bfree;
333 buf->f_files = sbi->s_ninodes;
334 buf->f_ffree = minix_count_free_inodes(sbi);
335 buf->f_namelen = sbi->s_namelen;
336 return 0;
339 static int minix_get_block(struct inode *inode, sector_t block,
340 struct buffer_head *bh_result, int create)
342 if (INODE_VERSION(inode) == MINIX_V1)
343 return V1_minix_get_block(inode, block, bh_result, create);
344 else
345 return V2_minix_get_block(inode, block, bh_result, create);
348 static int minix_writepage(struct page *page, struct writeback_control *wbc)
350 return block_write_full_page(page, minix_get_block, wbc);
353 static int minix_readpage(struct file *file, struct page *page)
355 return block_read_full_page(page,minix_get_block);
358 int __minix_write_begin(struct file *file, struct address_space *mapping,
359 loff_t pos, unsigned len, unsigned flags,
360 struct page **pagep, void **fsdata)
362 return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
363 minix_get_block);
366 static int minix_write_begin(struct file *file, struct address_space *mapping,
367 loff_t pos, unsigned len, unsigned flags,
368 struct page **pagep, void **fsdata)
370 *pagep = NULL;
371 return __minix_write_begin(file, mapping, pos, len, flags, pagep, fsdata);
374 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
376 return generic_block_bmap(mapping,block,minix_get_block);
379 static const struct address_space_operations minix_aops = {
380 .readpage = minix_readpage,
381 .writepage = minix_writepage,
382 .sync_page = block_sync_page,
383 .write_begin = minix_write_begin,
384 .write_end = generic_write_end,
385 .bmap = minix_bmap
388 static const struct inode_operations minix_symlink_inode_operations = {
389 .readlink = generic_readlink,
390 .follow_link = page_follow_link_light,
391 .put_link = page_put_link,
392 .getattr = minix_getattr,
395 void minix_set_inode(struct inode *inode, dev_t rdev)
397 if (S_ISREG(inode->i_mode)) {
398 inode->i_op = &minix_file_inode_operations;
399 inode->i_fop = &minix_file_operations;
400 inode->i_mapping->a_ops = &minix_aops;
401 } else if (S_ISDIR(inode->i_mode)) {
402 inode->i_op = &minix_dir_inode_operations;
403 inode->i_fop = &minix_dir_operations;
404 inode->i_mapping->a_ops = &minix_aops;
405 } else if (S_ISLNK(inode->i_mode)) {
406 inode->i_op = &minix_symlink_inode_operations;
407 inode->i_mapping->a_ops = &minix_aops;
408 } else
409 init_special_inode(inode, inode->i_mode, rdev);
413 * The minix V1 function to read an inode.
415 static struct inode *V1_minix_iget(struct inode *inode)
417 struct buffer_head * bh;
418 struct minix_inode * raw_inode;
419 struct minix_inode_info *minix_inode = minix_i(inode);
420 int i;
422 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
423 if (!raw_inode) {
424 iget_failed(inode);
425 return ERR_PTR(-EIO);
427 inode->i_mode = raw_inode->i_mode;
428 inode->i_uid = (uid_t)raw_inode->i_uid;
429 inode->i_gid = (gid_t)raw_inode->i_gid;
430 inode->i_nlink = raw_inode->i_nlinks;
431 inode->i_size = raw_inode->i_size;
432 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
433 inode->i_mtime.tv_nsec = 0;
434 inode->i_atime.tv_nsec = 0;
435 inode->i_ctime.tv_nsec = 0;
436 inode->i_blocks = 0;
437 for (i = 0; i < 9; i++)
438 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
439 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
440 brelse(bh);
441 unlock_new_inode(inode);
442 return inode;
446 * The minix V2 function to read an inode.
448 static struct inode *V2_minix_iget(struct inode *inode)
450 struct buffer_head * bh;
451 struct minix2_inode * raw_inode;
452 struct minix_inode_info *minix_inode = minix_i(inode);
453 int i;
455 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
456 if (!raw_inode) {
457 iget_failed(inode);
458 return ERR_PTR(-EIO);
460 inode->i_mode = raw_inode->i_mode;
461 inode->i_uid = (uid_t)raw_inode->i_uid;
462 inode->i_gid = (gid_t)raw_inode->i_gid;
463 inode->i_nlink = raw_inode->i_nlinks;
464 inode->i_size = raw_inode->i_size;
465 inode->i_mtime.tv_sec = raw_inode->i_mtime;
466 inode->i_atime.tv_sec = raw_inode->i_atime;
467 inode->i_ctime.tv_sec = raw_inode->i_ctime;
468 inode->i_mtime.tv_nsec = 0;
469 inode->i_atime.tv_nsec = 0;
470 inode->i_ctime.tv_nsec = 0;
471 inode->i_blocks = 0;
472 for (i = 0; i < 10; i++)
473 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
474 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
475 brelse(bh);
476 unlock_new_inode(inode);
477 return inode;
481 * The global function to read an inode.
483 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
485 struct inode *inode;
487 inode = iget_locked(sb, ino);
488 if (!inode)
489 return ERR_PTR(-ENOMEM);
490 if (!(inode->i_state & I_NEW))
491 return inode;
493 if (INODE_VERSION(inode) == MINIX_V1)
494 return V1_minix_iget(inode);
495 else
496 return V2_minix_iget(inode);
500 * The minix V1 function to synchronize an inode.
502 static struct buffer_head * V1_minix_update_inode(struct inode * inode)
504 struct buffer_head * bh;
505 struct minix_inode * raw_inode;
506 struct minix_inode_info *minix_inode = minix_i(inode);
507 int i;
509 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
510 if (!raw_inode)
511 return NULL;
512 raw_inode->i_mode = inode->i_mode;
513 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
514 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
515 raw_inode->i_nlinks = inode->i_nlink;
516 raw_inode->i_size = inode->i_size;
517 raw_inode->i_time = inode->i_mtime.tv_sec;
518 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
519 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
520 else for (i = 0; i < 9; i++)
521 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
522 mark_buffer_dirty(bh);
523 return bh;
527 * The minix V2 function to synchronize an inode.
529 static struct buffer_head * V2_minix_update_inode(struct inode * inode)
531 struct buffer_head * bh;
532 struct minix2_inode * raw_inode;
533 struct minix_inode_info *minix_inode = minix_i(inode);
534 int i;
536 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
537 if (!raw_inode)
538 return NULL;
539 raw_inode->i_mode = inode->i_mode;
540 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
541 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
542 raw_inode->i_nlinks = inode->i_nlink;
543 raw_inode->i_size = inode->i_size;
544 raw_inode->i_mtime = inode->i_mtime.tv_sec;
545 raw_inode->i_atime = inode->i_atime.tv_sec;
546 raw_inode->i_ctime = inode->i_ctime.tv_sec;
547 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
548 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
549 else for (i = 0; i < 10; i++)
550 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
551 mark_buffer_dirty(bh);
552 return bh;
555 static struct buffer_head *minix_update_inode(struct inode *inode)
557 if (INODE_VERSION(inode) == MINIX_V1)
558 return V1_minix_update_inode(inode);
559 else
560 return V2_minix_update_inode(inode);
563 static int minix_write_inode(struct inode * inode, int wait)
565 brelse(minix_update_inode(inode));
566 return 0;
569 int minix_sync_inode(struct inode * inode)
571 int err = 0;
572 struct buffer_head *bh;
574 bh = minix_update_inode(inode);
575 if (bh && buffer_dirty(bh))
577 sync_dirty_buffer(bh);
578 if (buffer_req(bh) && !buffer_uptodate(bh))
580 printk("IO error syncing minix inode [%s:%08lx]\n",
581 inode->i_sb->s_id, inode->i_ino);
582 err = -1;
585 else if (!bh)
586 err = -1;
587 brelse (bh);
588 return err;
591 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
593 struct inode *dir = dentry->d_parent->d_inode;
594 struct super_block *sb = dir->i_sb;
595 generic_fillattr(dentry->d_inode, stat);
596 if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
597 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
598 else
599 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
600 stat->blksize = sb->s_blocksize;
601 return 0;
605 * The function that is called for file truncation.
607 void minix_truncate(struct inode * inode)
609 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
610 return;
611 if (INODE_VERSION(inode) == MINIX_V1)
612 V1_minix_truncate(inode);
613 else
614 V2_minix_truncate(inode);
617 static int minix_get_sb(struct file_system_type *fs_type,
618 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
620 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super,
621 mnt);
624 static struct file_system_type minix_fs_type = {
625 .owner = THIS_MODULE,
626 .name = "minix",
627 .get_sb = minix_get_sb,
628 .kill_sb = kill_block_super,
629 .fs_flags = FS_REQUIRES_DEV,
632 static int __init init_minix_fs(void)
634 int err = init_inodecache();
635 if (err)
636 goto out1;
637 err = register_filesystem(&minix_fs_type);
638 if (err)
639 goto out;
640 return 0;
641 out:
642 destroy_inodecache();
643 out1:
644 return err;
647 static void __exit exit_minix_fs(void)
649 unregister_filesystem(&minix_fs_type);
650 destroy_inodecache();
653 module_init(init_minix_fs)
654 module_exit(exit_minix_fs)
655 MODULE_LICENSE("GPL");