Btrfs: async threads should try harder to find work
[linux/fpc-iii.git] / fs / minix / inode.c
blobd1d1eb84679d03ee19d62f7d4033c42d59ac2495
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(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 (!(s->s_flags & MS_RDONLY)) {
260 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
261 ms->s_state &= ~MINIX_VALID_FS;
262 mark_buffer_dirty(bh);
264 if (!(sbi->s_mount_state & MINIX_VALID_FS))
265 printk("MINIX-fs: mounting unchecked file system, "
266 "running fsck is recommended\n");
267 else if (sbi->s_mount_state & MINIX_ERROR_FS)
268 printk("MINIX-fs: mounting file system with errors, "
269 "running fsck is recommended\n");
270 return 0;
272 out_iput:
273 iput(root_inode);
274 goto out_freemap;
276 out_no_root:
277 if (!silent)
278 printk("MINIX-fs: get root inode failed\n");
279 goto out_freemap;
281 out_no_bitmap:
282 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
283 out_freemap:
284 for (i = 0; i < sbi->s_imap_blocks; i++)
285 brelse(sbi->s_imap[i]);
286 for (i = 0; i < sbi->s_zmap_blocks; i++)
287 brelse(sbi->s_zmap[i]);
288 kfree(sbi->s_imap);
289 goto out_release;
291 out_no_map:
292 ret = -ENOMEM;
293 if (!silent)
294 printk("MINIX-fs: can't allocate map\n");
295 goto out_release;
297 out_illegal_sb:
298 if (!silent)
299 printk("MINIX-fs: bad superblock\n");
300 goto out_release;
302 out_no_fs:
303 if (!silent)
304 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
305 "on device %s.\n", s->s_id);
306 out_release:
307 brelse(bh);
308 goto out;
310 out_bad_hblock:
311 printk("MINIX-fs: blocksize too small for device\n");
312 goto out;
314 out_bad_sb:
315 printk("MINIX-fs: unable to read superblock\n");
316 out:
317 s->s_fs_info = NULL;
318 kfree(sbi);
319 return ret;
322 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
324 struct minix_sb_info *sbi = minix_sb(dentry->d_sb);
325 buf->f_type = dentry->d_sb->s_magic;
326 buf->f_bsize = dentry->d_sb->s_blocksize;
327 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
328 buf->f_bfree = minix_count_free_blocks(sbi);
329 buf->f_bavail = buf->f_bfree;
330 buf->f_files = sbi->s_ninodes;
331 buf->f_ffree = minix_count_free_inodes(sbi);
332 buf->f_namelen = sbi->s_namelen;
333 return 0;
336 static int minix_get_block(struct inode *inode, sector_t block,
337 struct buffer_head *bh_result, int create)
339 if (INODE_VERSION(inode) == MINIX_V1)
340 return V1_minix_get_block(inode, block, bh_result, create);
341 else
342 return V2_minix_get_block(inode, block, bh_result, create);
345 static int minix_writepage(struct page *page, struct writeback_control *wbc)
347 return block_write_full_page(page, minix_get_block, wbc);
350 static int minix_readpage(struct file *file, struct page *page)
352 return block_read_full_page(page,minix_get_block);
355 int __minix_write_begin(struct file *file, struct address_space *mapping,
356 loff_t pos, unsigned len, unsigned flags,
357 struct page **pagep, void **fsdata)
359 return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
360 minix_get_block);
363 static int minix_write_begin(struct file *file, struct address_space *mapping,
364 loff_t pos, unsigned len, unsigned flags,
365 struct page **pagep, void **fsdata)
367 *pagep = NULL;
368 return __minix_write_begin(file, mapping, pos, len, flags, pagep, fsdata);
371 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
373 return generic_block_bmap(mapping,block,minix_get_block);
376 static const struct address_space_operations minix_aops = {
377 .readpage = minix_readpage,
378 .writepage = minix_writepage,
379 .sync_page = block_sync_page,
380 .write_begin = minix_write_begin,
381 .write_end = generic_write_end,
382 .bmap = minix_bmap
385 static const struct inode_operations minix_symlink_inode_operations = {
386 .readlink = generic_readlink,
387 .follow_link = page_follow_link_light,
388 .put_link = page_put_link,
389 .getattr = minix_getattr,
392 void minix_set_inode(struct inode *inode, dev_t rdev)
394 if (S_ISREG(inode->i_mode)) {
395 inode->i_op = &minix_file_inode_operations;
396 inode->i_fop = &minix_file_operations;
397 inode->i_mapping->a_ops = &minix_aops;
398 } else if (S_ISDIR(inode->i_mode)) {
399 inode->i_op = &minix_dir_inode_operations;
400 inode->i_fop = &minix_dir_operations;
401 inode->i_mapping->a_ops = &minix_aops;
402 } else if (S_ISLNK(inode->i_mode)) {
403 inode->i_op = &minix_symlink_inode_operations;
404 inode->i_mapping->a_ops = &minix_aops;
405 } else
406 init_special_inode(inode, inode->i_mode, rdev);
410 * The minix V1 function to read an inode.
412 static struct inode *V1_minix_iget(struct inode *inode)
414 struct buffer_head * bh;
415 struct minix_inode * raw_inode;
416 struct minix_inode_info *minix_inode = minix_i(inode);
417 int i;
419 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
420 if (!raw_inode) {
421 iget_failed(inode);
422 return ERR_PTR(-EIO);
424 inode->i_mode = raw_inode->i_mode;
425 inode->i_uid = (uid_t)raw_inode->i_uid;
426 inode->i_gid = (gid_t)raw_inode->i_gid;
427 inode->i_nlink = raw_inode->i_nlinks;
428 inode->i_size = raw_inode->i_size;
429 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
430 inode->i_mtime.tv_nsec = 0;
431 inode->i_atime.tv_nsec = 0;
432 inode->i_ctime.tv_nsec = 0;
433 inode->i_blocks = 0;
434 for (i = 0; i < 9; i++)
435 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
436 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
437 brelse(bh);
438 unlock_new_inode(inode);
439 return inode;
443 * The minix V2 function to read an inode.
445 static struct inode *V2_minix_iget(struct inode *inode)
447 struct buffer_head * bh;
448 struct minix2_inode * raw_inode;
449 struct minix_inode_info *minix_inode = minix_i(inode);
450 int i;
452 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
453 if (!raw_inode) {
454 iget_failed(inode);
455 return ERR_PTR(-EIO);
457 inode->i_mode = raw_inode->i_mode;
458 inode->i_uid = (uid_t)raw_inode->i_uid;
459 inode->i_gid = (gid_t)raw_inode->i_gid;
460 inode->i_nlink = raw_inode->i_nlinks;
461 inode->i_size = raw_inode->i_size;
462 inode->i_mtime.tv_sec = raw_inode->i_mtime;
463 inode->i_atime.tv_sec = raw_inode->i_atime;
464 inode->i_ctime.tv_sec = raw_inode->i_ctime;
465 inode->i_mtime.tv_nsec = 0;
466 inode->i_atime.tv_nsec = 0;
467 inode->i_ctime.tv_nsec = 0;
468 inode->i_blocks = 0;
469 for (i = 0; i < 10; i++)
470 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
471 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
472 brelse(bh);
473 unlock_new_inode(inode);
474 return inode;
478 * The global function to read an inode.
480 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
482 struct inode *inode;
484 inode = iget_locked(sb, ino);
485 if (!inode)
486 return ERR_PTR(-ENOMEM);
487 if (!(inode->i_state & I_NEW))
488 return inode;
490 if (INODE_VERSION(inode) == MINIX_V1)
491 return V1_minix_iget(inode);
492 else
493 return V2_minix_iget(inode);
497 * The minix V1 function to synchronize an inode.
499 static struct buffer_head * V1_minix_update_inode(struct inode * inode)
501 struct buffer_head * bh;
502 struct minix_inode * raw_inode;
503 struct minix_inode_info *minix_inode = minix_i(inode);
504 int i;
506 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
507 if (!raw_inode)
508 return NULL;
509 raw_inode->i_mode = inode->i_mode;
510 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
511 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
512 raw_inode->i_nlinks = inode->i_nlink;
513 raw_inode->i_size = inode->i_size;
514 raw_inode->i_time = inode->i_mtime.tv_sec;
515 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
516 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
517 else for (i = 0; i < 9; i++)
518 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
519 mark_buffer_dirty(bh);
520 return bh;
524 * The minix V2 function to synchronize an inode.
526 static struct buffer_head * V2_minix_update_inode(struct inode * inode)
528 struct buffer_head * bh;
529 struct minix2_inode * raw_inode;
530 struct minix_inode_info *minix_inode = minix_i(inode);
531 int i;
533 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
534 if (!raw_inode)
535 return NULL;
536 raw_inode->i_mode = inode->i_mode;
537 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
538 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
539 raw_inode->i_nlinks = inode->i_nlink;
540 raw_inode->i_size = inode->i_size;
541 raw_inode->i_mtime = inode->i_mtime.tv_sec;
542 raw_inode->i_atime = inode->i_atime.tv_sec;
543 raw_inode->i_ctime = inode->i_ctime.tv_sec;
544 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
545 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
546 else for (i = 0; i < 10; i++)
547 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
548 mark_buffer_dirty(bh);
549 return bh;
552 static struct buffer_head *minix_update_inode(struct inode *inode)
554 if (INODE_VERSION(inode) == MINIX_V1)
555 return V1_minix_update_inode(inode);
556 else
557 return V2_minix_update_inode(inode);
560 static int minix_write_inode(struct inode * inode, int wait)
562 brelse(minix_update_inode(inode));
563 return 0;
566 int minix_sync_inode(struct inode * inode)
568 int err = 0;
569 struct buffer_head *bh;
571 bh = minix_update_inode(inode);
572 if (bh && buffer_dirty(bh))
574 sync_dirty_buffer(bh);
575 if (buffer_req(bh) && !buffer_uptodate(bh))
577 printk("IO error syncing minix inode [%s:%08lx]\n",
578 inode->i_sb->s_id, inode->i_ino);
579 err = -1;
582 else if (!bh)
583 err = -1;
584 brelse (bh);
585 return err;
588 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
590 struct inode *dir = dentry->d_parent->d_inode;
591 struct super_block *sb = dir->i_sb;
592 generic_fillattr(dentry->d_inode, stat);
593 if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
594 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
595 else
596 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
597 stat->blksize = sb->s_blocksize;
598 return 0;
602 * The function that is called for file truncation.
604 void minix_truncate(struct inode * inode)
606 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
607 return;
608 if (INODE_VERSION(inode) == MINIX_V1)
609 V1_minix_truncate(inode);
610 else
611 V2_minix_truncate(inode);
614 static int minix_get_sb(struct file_system_type *fs_type,
615 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
617 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super,
618 mnt);
621 static struct file_system_type minix_fs_type = {
622 .owner = THIS_MODULE,
623 .name = "minix",
624 .get_sb = minix_get_sb,
625 .kill_sb = kill_block_super,
626 .fs_flags = FS_REQUIRES_DEV,
629 static int __init init_minix_fs(void)
631 int err = init_inodecache();
632 if (err)
633 goto out1;
634 err = register_filesystem(&minix_fs_type);
635 if (err)
636 goto out;
637 return 0;
638 out:
639 destroy_inodecache();
640 out1:
641 return err;
644 static void __exit exit_minix_fs(void)
646 unregister_filesystem(&minix_fs_type);
647 destroy_inodecache();
650 module_init(init_minix_fs)
651 module_exit(exit_minix_fs)
652 MODULE_LICENSE("GPL");