eeepc-laptop: fix use after free
[linux-2.6/mini2440.git] / fs / hfs / inode.c
blob7e19835efa2ea91675980a18e963281a02d46bb8
1 /*
2 * linux/fs/hfs/inode.c
4 * Copyright (C) 1995-1997 Paul H. Hargrove
5 * (C) 2003 Ardis Technologies <roman@ardistech.com>
6 * This file may be distributed under the terms of the GNU General Public License.
8 * This file contains inode-related functions which do not depend on
9 * which scheme is being used to represent forks.
11 * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
14 #include <linux/pagemap.h>
15 #include <linux/mpage.h>
16 #include <linux/sched.h>
18 #include "hfs_fs.h"
19 #include "btree.h"
21 static const struct file_operations hfs_file_operations;
22 static const struct inode_operations hfs_file_inode_operations;
24 /*================ Variable-like macros ================*/
26 #define HFS_VALID_MODE_BITS (S_IFREG | S_IFDIR | S_IRWXUGO)
28 static int hfs_writepage(struct page *page, struct writeback_control *wbc)
30 return block_write_full_page(page, hfs_get_block, wbc);
33 static int hfs_readpage(struct file *file, struct page *page)
35 return block_read_full_page(page, hfs_get_block);
38 static int hfs_write_begin(struct file *file, struct address_space *mapping,
39 loff_t pos, unsigned len, unsigned flags,
40 struct page **pagep, void **fsdata)
42 *pagep = NULL;
43 return cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
44 hfs_get_block,
45 &HFS_I(mapping->host)->phys_size);
48 static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
50 return generic_block_bmap(mapping, block, hfs_get_block);
53 static int hfs_releasepage(struct page *page, gfp_t mask)
55 struct inode *inode = page->mapping->host;
56 struct super_block *sb = inode->i_sb;
57 struct hfs_btree *tree;
58 struct hfs_bnode *node;
59 u32 nidx;
60 int i, res = 1;
62 switch (inode->i_ino) {
63 case HFS_EXT_CNID:
64 tree = HFS_SB(sb)->ext_tree;
65 break;
66 case HFS_CAT_CNID:
67 tree = HFS_SB(sb)->cat_tree;
68 break;
69 default:
70 BUG();
71 return 0;
73 if (tree->node_size >= PAGE_CACHE_SIZE) {
74 nidx = page->index >> (tree->node_size_shift - PAGE_CACHE_SHIFT);
75 spin_lock(&tree->hash_lock);
76 node = hfs_bnode_findhash(tree, nidx);
77 if (!node)
79 else if (atomic_read(&node->refcnt))
80 res = 0;
81 if (res && node) {
82 hfs_bnode_unhash(node);
83 hfs_bnode_free(node);
85 spin_unlock(&tree->hash_lock);
86 } else {
87 nidx = page->index << (PAGE_CACHE_SHIFT - tree->node_size_shift);
88 i = 1 << (PAGE_CACHE_SHIFT - tree->node_size_shift);
89 spin_lock(&tree->hash_lock);
90 do {
91 node = hfs_bnode_findhash(tree, nidx++);
92 if (!node)
93 continue;
94 if (atomic_read(&node->refcnt)) {
95 res = 0;
96 break;
98 hfs_bnode_unhash(node);
99 hfs_bnode_free(node);
100 } while (--i && nidx < tree->node_count);
101 spin_unlock(&tree->hash_lock);
103 return res ? try_to_free_buffers(page) : 0;
106 static ssize_t hfs_direct_IO(int rw, struct kiocb *iocb,
107 const struct iovec *iov, loff_t offset, unsigned long nr_segs)
109 struct file *file = iocb->ki_filp;
110 struct inode *inode = file->f_path.dentry->d_inode->i_mapping->host;
112 return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
113 offset, nr_segs, hfs_get_block, NULL);
116 static int hfs_writepages(struct address_space *mapping,
117 struct writeback_control *wbc)
119 return mpage_writepages(mapping, wbc, hfs_get_block);
122 const struct address_space_operations hfs_btree_aops = {
123 .readpage = hfs_readpage,
124 .writepage = hfs_writepage,
125 .sync_page = block_sync_page,
126 .write_begin = hfs_write_begin,
127 .write_end = generic_write_end,
128 .bmap = hfs_bmap,
129 .releasepage = hfs_releasepage,
132 const struct address_space_operations hfs_aops = {
133 .readpage = hfs_readpage,
134 .writepage = hfs_writepage,
135 .sync_page = block_sync_page,
136 .write_begin = hfs_write_begin,
137 .write_end = generic_write_end,
138 .bmap = hfs_bmap,
139 .direct_IO = hfs_direct_IO,
140 .writepages = hfs_writepages,
144 * hfs_new_inode
146 struct inode *hfs_new_inode(struct inode *dir, struct qstr *name, int mode)
148 struct super_block *sb = dir->i_sb;
149 struct inode *inode = new_inode(sb);
150 if (!inode)
151 return NULL;
153 mutex_init(&HFS_I(inode)->extents_lock);
154 INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
155 hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
156 inode->i_ino = HFS_SB(sb)->next_id++;
157 inode->i_mode = mode;
158 inode->i_uid = current->fsuid;
159 inode->i_gid = current->fsgid;
160 inode->i_nlink = 1;
161 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
162 HFS_I(inode)->flags = 0;
163 HFS_I(inode)->rsrc_inode = NULL;
164 HFS_I(inode)->fs_blocks = 0;
165 if (S_ISDIR(mode)) {
166 inode->i_size = 2;
167 HFS_SB(sb)->folder_count++;
168 if (dir->i_ino == HFS_ROOT_CNID)
169 HFS_SB(sb)->root_dirs++;
170 inode->i_op = &hfs_dir_inode_operations;
171 inode->i_fop = &hfs_dir_operations;
172 inode->i_mode |= S_IRWXUGO;
173 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask;
174 } else if (S_ISREG(mode)) {
175 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
176 HFS_SB(sb)->file_count++;
177 if (dir->i_ino == HFS_ROOT_CNID)
178 HFS_SB(sb)->root_files++;
179 inode->i_op = &hfs_file_inode_operations;
180 inode->i_fop = &hfs_file_operations;
181 inode->i_mapping->a_ops = &hfs_aops;
182 inode->i_mode |= S_IRUGO|S_IXUGO;
183 if (mode & S_IWUSR)
184 inode->i_mode |= S_IWUGO;
185 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask;
186 HFS_I(inode)->phys_size = 0;
187 HFS_I(inode)->alloc_blocks = 0;
188 HFS_I(inode)->first_blocks = 0;
189 HFS_I(inode)->cached_start = 0;
190 HFS_I(inode)->cached_blocks = 0;
191 memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
192 memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
194 insert_inode_hash(inode);
195 mark_inode_dirty(inode);
196 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
197 sb->s_dirt = 1;
199 return inode;
202 void hfs_delete_inode(struct inode *inode)
204 struct super_block *sb = inode->i_sb;
206 dprint(DBG_INODE, "delete_inode: %lu\n", inode->i_ino);
207 if (S_ISDIR(inode->i_mode)) {
208 HFS_SB(sb)->folder_count--;
209 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
210 HFS_SB(sb)->root_dirs--;
211 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
212 sb->s_dirt = 1;
213 return;
215 HFS_SB(sb)->file_count--;
216 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
217 HFS_SB(sb)->root_files--;
218 if (S_ISREG(inode->i_mode)) {
219 if (!inode->i_nlink) {
220 inode->i_size = 0;
221 hfs_file_truncate(inode);
224 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
225 sb->s_dirt = 1;
228 void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
229 __be32 __log_size, __be32 phys_size, u32 clump_size)
231 struct super_block *sb = inode->i_sb;
232 u32 log_size = be32_to_cpu(__log_size);
233 u16 count;
234 int i;
236 memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
237 for (count = 0, i = 0; i < 3; i++)
238 count += be16_to_cpu(ext[i].count);
239 HFS_I(inode)->first_blocks = count;
241 inode->i_size = HFS_I(inode)->phys_size = log_size;
242 HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
243 inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits);
244 HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
245 HFS_SB(sb)->alloc_blksz;
246 HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
247 if (!HFS_I(inode)->clump_blocks)
248 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
251 struct hfs_iget_data {
252 struct hfs_cat_key *key;
253 hfs_cat_rec *rec;
256 static int hfs_test_inode(struct inode *inode, void *data)
258 struct hfs_iget_data *idata = data;
259 hfs_cat_rec *rec;
261 rec = idata->rec;
262 switch (rec->type) {
263 case HFS_CDR_DIR:
264 return inode->i_ino == be32_to_cpu(rec->dir.DirID);
265 case HFS_CDR_FIL:
266 return inode->i_ino == be32_to_cpu(rec->file.FlNum);
267 default:
268 BUG();
269 return 1;
274 * hfs_read_inode
276 static int hfs_read_inode(struct inode *inode, void *data)
278 struct hfs_iget_data *idata = data;
279 struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
280 hfs_cat_rec *rec;
282 HFS_I(inode)->flags = 0;
283 HFS_I(inode)->rsrc_inode = NULL;
284 mutex_init(&HFS_I(inode)->extents_lock);
285 INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
287 /* Initialize the inode */
288 inode->i_uid = hsb->s_uid;
289 inode->i_gid = hsb->s_gid;
290 inode->i_nlink = 1;
292 if (idata->key)
293 HFS_I(inode)->cat_key = *idata->key;
294 else
295 HFS_I(inode)->flags |= HFS_FLG_RSRC;
296 HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
298 rec = idata->rec;
299 switch (rec->type) {
300 case HFS_CDR_FIL:
301 if (!HFS_IS_RSRC(inode)) {
302 hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
303 rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
304 } else {
305 hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
306 rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
309 inode->i_ino = be32_to_cpu(rec->file.FlNum);
310 inode->i_mode = S_IRUGO | S_IXUGO;
311 if (!(rec->file.Flags & HFS_FIL_LOCK))
312 inode->i_mode |= S_IWUGO;
313 inode->i_mode &= ~hsb->s_file_umask;
314 inode->i_mode |= S_IFREG;
315 inode->i_ctime = inode->i_atime = inode->i_mtime =
316 hfs_m_to_utime(rec->file.MdDat);
317 inode->i_op = &hfs_file_inode_operations;
318 inode->i_fop = &hfs_file_operations;
319 inode->i_mapping->a_ops = &hfs_aops;
320 break;
321 case HFS_CDR_DIR:
322 inode->i_ino = be32_to_cpu(rec->dir.DirID);
323 inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
324 HFS_I(inode)->fs_blocks = 0;
325 inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
326 inode->i_ctime = inode->i_atime = inode->i_mtime =
327 hfs_m_to_utime(rec->dir.MdDat);
328 inode->i_op = &hfs_dir_inode_operations;
329 inode->i_fop = &hfs_dir_operations;
330 break;
331 default:
332 make_bad_inode(inode);
334 return 0;
338 * __hfs_iget()
340 * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
341 * the catalog B-tree and the 'type' of the desired file return the
342 * inode for that file/directory or NULL. Note that 'type' indicates
343 * whether we want the actual file or directory, or the corresponding
344 * metadata (AppleDouble header file or CAP metadata file).
346 struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
348 struct hfs_iget_data data = { key, rec };
349 struct inode *inode;
350 u32 cnid;
352 switch (rec->type) {
353 case HFS_CDR_DIR:
354 cnid = be32_to_cpu(rec->dir.DirID);
355 break;
356 case HFS_CDR_FIL:
357 cnid = be32_to_cpu(rec->file.FlNum);
358 break;
359 default:
360 return NULL;
362 inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
363 if (inode && (inode->i_state & I_NEW))
364 unlock_new_inode(inode);
365 return inode;
368 void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
369 __be32 *log_size, __be32 *phys_size)
371 memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
373 if (log_size)
374 *log_size = cpu_to_be32(inode->i_size);
375 if (phys_size)
376 *phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
377 HFS_SB(inode->i_sb)->alloc_blksz);
380 int hfs_write_inode(struct inode *inode, int unused)
382 struct inode *main_inode = inode;
383 struct hfs_find_data fd;
384 hfs_cat_rec rec;
386 dprint(DBG_INODE, "hfs_write_inode: %lu\n", inode->i_ino);
387 hfs_ext_write_extent(inode);
389 if (inode->i_ino < HFS_FIRSTUSER_CNID) {
390 switch (inode->i_ino) {
391 case HFS_ROOT_CNID:
392 break;
393 case HFS_EXT_CNID:
394 hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
395 return 0;
396 case HFS_CAT_CNID:
397 hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
398 return 0;
399 default:
400 BUG();
401 return -EIO;
405 if (HFS_IS_RSRC(inode))
406 main_inode = HFS_I(inode)->rsrc_inode;
408 if (!main_inode->i_nlink)
409 return 0;
411 if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
412 /* panic? */
413 return -EIO;
415 fd.search_key->cat = HFS_I(main_inode)->cat_key;
416 if (hfs_brec_find(&fd))
417 /* panic? */
418 goto out;
420 if (S_ISDIR(main_inode->i_mode)) {
421 if (fd.entrylength < sizeof(struct hfs_cat_dir))
422 /* panic? */;
423 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
424 sizeof(struct hfs_cat_dir));
425 if (rec.type != HFS_CDR_DIR ||
426 be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
429 rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
430 rec.dir.Val = cpu_to_be16(inode->i_size - 2);
432 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
433 sizeof(struct hfs_cat_dir));
434 } else if (HFS_IS_RSRC(inode)) {
435 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
436 sizeof(struct hfs_cat_file));
437 hfs_inode_write_fork(inode, rec.file.RExtRec,
438 &rec.file.RLgLen, &rec.file.RPyLen);
439 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
440 sizeof(struct hfs_cat_file));
441 } else {
442 if (fd.entrylength < sizeof(struct hfs_cat_file))
443 /* panic? */;
444 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
445 sizeof(struct hfs_cat_file));
446 if (rec.type != HFS_CDR_FIL ||
447 be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
450 if (inode->i_mode & S_IWUSR)
451 rec.file.Flags &= ~HFS_FIL_LOCK;
452 else
453 rec.file.Flags |= HFS_FIL_LOCK;
454 hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
455 rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);
457 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
458 sizeof(struct hfs_cat_file));
460 out:
461 hfs_find_exit(&fd);
462 return 0;
465 static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
466 struct nameidata *nd)
468 struct inode *inode = NULL;
469 hfs_cat_rec rec;
470 struct hfs_find_data fd;
471 int res;
473 if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
474 goto out;
476 inode = HFS_I(dir)->rsrc_inode;
477 if (inode)
478 goto out;
480 inode = new_inode(dir->i_sb);
481 if (!inode)
482 return ERR_PTR(-ENOMEM);
484 hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
485 fd.search_key->cat = HFS_I(dir)->cat_key;
486 res = hfs_brec_read(&fd, &rec, sizeof(rec));
487 if (!res) {
488 struct hfs_iget_data idata = { NULL, &rec };
489 hfs_read_inode(inode, &idata);
491 hfs_find_exit(&fd);
492 if (res) {
493 iput(inode);
494 return ERR_PTR(res);
496 HFS_I(inode)->rsrc_inode = dir;
497 HFS_I(dir)->rsrc_inode = inode;
498 igrab(dir);
499 hlist_add_head(&inode->i_hash, &HFS_SB(dir->i_sb)->rsrc_inodes);
500 mark_inode_dirty(inode);
501 out:
502 d_add(dentry, inode);
503 return NULL;
506 void hfs_clear_inode(struct inode *inode)
508 if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
509 HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
510 iput(HFS_I(inode)->rsrc_inode);
514 static int hfs_permission(struct inode *inode, int mask)
516 if (S_ISREG(inode->i_mode) && mask & MAY_EXEC)
517 return 0;
518 return generic_permission(inode, mask, NULL);
521 static int hfs_file_open(struct inode *inode, struct file *file)
523 if (HFS_IS_RSRC(inode))
524 inode = HFS_I(inode)->rsrc_inode;
525 atomic_inc(&HFS_I(inode)->opencnt);
526 return 0;
529 static int hfs_file_release(struct inode *inode, struct file *file)
531 //struct super_block *sb = inode->i_sb;
533 if (HFS_IS_RSRC(inode))
534 inode = HFS_I(inode)->rsrc_inode;
535 if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
536 mutex_lock(&inode->i_mutex);
537 hfs_file_truncate(inode);
538 //if (inode->i_flags & S_DEAD) {
539 // hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
540 // hfs_delete_inode(inode);
542 mutex_unlock(&inode->i_mutex);
544 return 0;
548 * hfs_notify_change()
550 * Based very closely on fs/msdos/inode.c by Werner Almesberger
552 * This is the notify_change() field in the super_operations structure
553 * for HFS file systems. The purpose is to take that changes made to
554 * an inode and apply then in a filesystem-dependent manner. In this
555 * case the process has a few of tasks to do:
556 * 1) prevent changes to the i_uid and i_gid fields.
557 * 2) map file permissions to the closest allowable permissions
558 * 3) Since multiple Linux files can share the same on-disk inode under
559 * HFS (for instance the data and resource forks of a file) a change
560 * to permissions must be applied to all other in-core inodes which
561 * correspond to the same HFS file.
564 int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
566 struct inode *inode = dentry->d_inode;
567 struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
568 int error;
570 error = inode_change_ok(inode, attr); /* basic permission checks */
571 if (error)
572 return error;
574 /* no uig/gid changes and limit which mode bits can be set */
575 if (((attr->ia_valid & ATTR_UID) &&
576 (attr->ia_uid != hsb->s_uid)) ||
577 ((attr->ia_valid & ATTR_GID) &&
578 (attr->ia_gid != hsb->s_gid)) ||
579 ((attr->ia_valid & ATTR_MODE) &&
580 ((S_ISDIR(inode->i_mode) &&
581 (attr->ia_mode != inode->i_mode)) ||
582 (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
583 return hsb->s_quiet ? 0 : error;
586 if (attr->ia_valid & ATTR_MODE) {
587 /* Only the 'w' bits can ever change and only all together. */
588 if (attr->ia_mode & S_IWUSR)
589 attr->ia_mode = inode->i_mode | S_IWUGO;
590 else
591 attr->ia_mode = inode->i_mode & ~S_IWUGO;
592 attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
594 error = inode_setattr(inode, attr);
595 if (error)
596 return error;
598 return 0;
602 static const struct file_operations hfs_file_operations = {
603 .llseek = generic_file_llseek,
604 .read = do_sync_read,
605 .aio_read = generic_file_aio_read,
606 .write = do_sync_write,
607 .aio_write = generic_file_aio_write,
608 .mmap = generic_file_mmap,
609 .splice_read = generic_file_splice_read,
610 .fsync = file_fsync,
611 .open = hfs_file_open,
612 .release = hfs_file_release,
615 static const struct inode_operations hfs_file_inode_operations = {
616 .lookup = hfs_file_lookup,
617 .truncate = hfs_file_truncate,
618 .setattr = hfs_inode_setattr,
619 .permission = hfs_permission,
620 .setxattr = hfs_setxattr,
621 .getxattr = hfs_getxattr,
622 .listxattr = hfs_listxattr,