1 /*
2 * linux/fs/hfs/inode.c
3 *
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.
7 *
8 * This file contains inode-related functions which do not depend on
9 * which scheme is being used to represent forks.
10 *
11 * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
12 */
13
14 #include <linux/pagemap.h>
15 #include <linux/mpage.h>
16 #include <linux/sched.h>
17 #include <linux/cred.h>
18 #include <linux/uio.h>
19 #include <linux/xattr.h>
20 #include <linux/blkdev.h>
21
22 #include "hfs_fs.h"
23 #include "btree.h"
24
25 static const struct file_operations hfs_file_operations;
26 static const struct inode_operations hfs_file_inode_operations;
27
28 /*================ Variable-like macros ================*/
29
30 #define HFS_VALID_MODE_BITS (S_IFREG | S_IFDIR | S_IRWXUGO)
31
hfs_writepage(struct page * page,struct writeback_control * wbc)32 static int hfs_writepage(struct page *page, struct writeback_control *wbc)
33 {
34 return block_write_full_page(page, hfs_get_block, wbc);
35 }
36
hfs_readpage(struct file * file,struct page * page)37 static int hfs_readpage(struct file *file, struct page *page)
38 {
39 return block_read_full_page(page, hfs_get_block);
40 }
41
hfs_write_failed(struct address_space * mapping,loff_t to)42 static void hfs_write_failed(struct address_space *mapping, loff_t to)
43 {
44 struct inode *inode = mapping->host;
45
46 if (to > inode->i_size) {
47 truncate_pagecache(inode, inode->i_size);
48 hfs_file_truncate(inode);
49 }
50 }
51
hfs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned flags,struct page ** pagep,void ** fsdata)52 static int hfs_write_begin(struct file *file, struct address_space *mapping,
53 loff_t pos, unsigned len, unsigned flags,
54 struct page **pagep, void **fsdata)
55 {
56 int ret;
57
58 *pagep = NULL;
59 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
60 hfs_get_block,
61 &HFS_I(mapping->host)->phys_size);
62 if (unlikely(ret))
63 hfs_write_failed(mapping, pos + len);
64
65 return ret;
66 }
67
hfs_bmap(struct address_space * mapping,sector_t block)68 static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
69 {
70 return generic_block_bmap(mapping, block, hfs_get_block);
71 }
72
hfs_releasepage(struct page * page,gfp_t mask)73 static int hfs_releasepage(struct page *page, gfp_t mask)
74 {
75 struct inode *inode = page->mapping->host;
76 struct super_block *sb = inode->i_sb;
77 struct hfs_btree *tree;
78 struct hfs_bnode *node;
79 u32 nidx;
80 int i, res = 1;
81
82 switch (inode->i_ino) {
83 case HFS_EXT_CNID:
84 tree = HFS_SB(sb)->ext_tree;
85 break;
86 case HFS_CAT_CNID:
87 tree = HFS_SB(sb)->cat_tree;
88 break;
89 default:
90 BUG();
91 return 0;
92 }
93
94 if (!tree)
95 return 0;
96
97 if (tree->node_size >= PAGE_SIZE) {
98 nidx = page->index >> (tree->node_size_shift - PAGE_SHIFT);
99 spin_lock(&tree->hash_lock);
100 node = hfs_bnode_findhash(tree, nidx);
101 if (!node)
102 ;
103 else if (atomic_read(&node->refcnt))
104 res = 0;
105 if (res && node) {
106 hfs_bnode_unhash(node);
107 hfs_bnode_free(node);
108 }
109 spin_unlock(&tree->hash_lock);
110 } else {
111 nidx = page->index << (PAGE_SHIFT - tree->node_size_shift);
112 i = 1 << (PAGE_SHIFT - tree->node_size_shift);
113 spin_lock(&tree->hash_lock);
114 do {
115 node = hfs_bnode_findhash(tree, nidx++);
116 if (!node)
117 continue;
118 if (atomic_read(&node->refcnt)) {
119 res = 0;
120 break;
121 }
122 hfs_bnode_unhash(node);
123 hfs_bnode_free(node);
124 } while (--i && nidx < tree->node_count);
125 spin_unlock(&tree->hash_lock);
126 }
127 return res ? try_to_free_buffers(page) : 0;
128 }
129
hfs_direct_IO(struct kiocb * iocb,struct iov_iter * iter)130 static ssize_t hfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
131 {
132 struct file *file = iocb->ki_filp;
133 struct address_space *mapping = file->f_mapping;
134 struct inode *inode = mapping->host;
135 size_t count = iov_iter_count(iter);
136 ssize_t ret;
137
138 ret = blockdev_direct_IO(iocb, inode, iter, hfs_get_block);
139
140 /*
141 * In case of error extending write may have instantiated a few
142 * blocks outside i_size. Trim these off again.
143 */
144 if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) {
145 loff_t isize = i_size_read(inode);
146 loff_t end = iocb->ki_pos + count;
147
148 if (end > isize)
149 hfs_write_failed(mapping, end);
150 }
151
152 return ret;
153 }
154
hfs_writepages(struct address_space * mapping,struct writeback_control * wbc)155 static int hfs_writepages(struct address_space *mapping,
156 struct writeback_control *wbc)
157 {
158 return mpage_writepages(mapping, wbc, hfs_get_block);
159 }
160
161 const struct address_space_operations hfs_btree_aops = {
162 .readpage = hfs_readpage,
163 .writepage = hfs_writepage,
164 .write_begin = hfs_write_begin,
165 .write_end = generic_write_end,
166 .bmap = hfs_bmap,
167 .releasepage = hfs_releasepage,
168 };
169
170 const struct address_space_operations hfs_aops = {
171 .readpage = hfs_readpage,
172 .writepage = hfs_writepage,
173 .write_begin = hfs_write_begin,
174 .write_end = generic_write_end,
175 .bmap = hfs_bmap,
176 .direct_IO = hfs_direct_IO,
177 .writepages = hfs_writepages,
178 };
179
180 /*
181 * hfs_new_inode
182 */
hfs_new_inode(struct inode * dir,const struct qstr * name,umode_t mode)183 struct inode *hfs_new_inode(struct inode *dir, const struct qstr *name, umode_t mode)
184 {
185 struct super_block *sb = dir->i_sb;
186 struct inode *inode = new_inode(sb);
187 if (!inode)
188 return NULL;
189
190 mutex_init(&HFS_I(inode)->extents_lock);
191 INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
192 spin_lock_init(&HFS_I(inode)->open_dir_lock);
193 hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
194 inode->i_ino = HFS_SB(sb)->next_id++;
195 inode->i_mode = mode;
196 inode->i_uid = current_fsuid();
197 inode->i_gid = current_fsgid();
198 set_nlink(inode, 1);
199 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
200 HFS_I(inode)->flags = 0;
201 HFS_I(inode)->rsrc_inode = NULL;
202 HFS_I(inode)->fs_blocks = 0;
203 if (S_ISDIR(mode)) {
204 inode->i_size = 2;
205 HFS_SB(sb)->folder_count++;
206 if (dir->i_ino == HFS_ROOT_CNID)
207 HFS_SB(sb)->root_dirs++;
208 inode->i_op = &hfs_dir_inode_operations;
209 inode->i_fop = &hfs_dir_operations;
210 inode->i_mode |= S_IRWXUGO;
211 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask;
212 } else if (S_ISREG(mode)) {
213 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
214 HFS_SB(sb)->file_count++;
215 if (dir->i_ino == HFS_ROOT_CNID)
216 HFS_SB(sb)->root_files++;
217 inode->i_op = &hfs_file_inode_operations;
218 inode->i_fop = &hfs_file_operations;
219 inode->i_mapping->a_ops = &hfs_aops;
220 inode->i_mode |= S_IRUGO|S_IXUGO;
221 if (mode & S_IWUSR)
222 inode->i_mode |= S_IWUGO;
223 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask;
224 HFS_I(inode)->phys_size = 0;
225 HFS_I(inode)->alloc_blocks = 0;
226 HFS_I(inode)->first_blocks = 0;
227 HFS_I(inode)->cached_start = 0;
228 HFS_I(inode)->cached_blocks = 0;
229 memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
230 memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
231 }
232 insert_inode_hash(inode);
233 mark_inode_dirty(inode);
234 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
235 hfs_mark_mdb_dirty(sb);
236
237 return inode;
238 }
239
hfs_delete_inode(struct inode * inode)240 void hfs_delete_inode(struct inode *inode)
241 {
242 struct super_block *sb = inode->i_sb;
243
244 hfs_dbg(INODE, "delete_inode: %lu\n", inode->i_ino);
245 if (S_ISDIR(inode->i_mode)) {
246 HFS_SB(sb)->folder_count--;
247 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
248 HFS_SB(sb)->root_dirs--;
249 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
250 hfs_mark_mdb_dirty(sb);
251 return;
252 }
253 HFS_SB(sb)->file_count--;
254 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
255 HFS_SB(sb)->root_files--;
256 if (S_ISREG(inode->i_mode)) {
257 if (!inode->i_nlink) {
258 inode->i_size = 0;
259 hfs_file_truncate(inode);
260 }
261 }
262 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
263 hfs_mark_mdb_dirty(sb);
264 }
265
hfs_inode_read_fork(struct inode * inode,struct hfs_extent * ext,__be32 __log_size,__be32 phys_size,u32 clump_size)266 void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
267 __be32 __log_size, __be32 phys_size, u32 clump_size)
268 {
269 struct super_block *sb = inode->i_sb;
270 u32 log_size = be32_to_cpu(__log_size);
271 u16 count;
272 int i;
273
274 memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
275 for (count = 0, i = 0; i < 3; i++)
276 count += be16_to_cpu(ext[i].count);
277 HFS_I(inode)->first_blocks = count;
278
279 inode->i_size = HFS_I(inode)->phys_size = log_size;
280 HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
281 inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits);
282 HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
283 HFS_SB(sb)->alloc_blksz;
284 HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
285 if (!HFS_I(inode)->clump_blocks)
286 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
287 }
288
289 struct hfs_iget_data {
290 struct hfs_cat_key *key;
291 hfs_cat_rec *rec;
292 };
293
hfs_test_inode(struct inode * inode,void * data)294 static int hfs_test_inode(struct inode *inode, void *data)
295 {
296 struct hfs_iget_data *idata = data;
297 hfs_cat_rec *rec;
298
299 rec = idata->rec;
300 switch (rec->type) {
301 case HFS_CDR_DIR:
302 return inode->i_ino == be32_to_cpu(rec->dir.DirID);
303 case HFS_CDR_FIL:
304 return inode->i_ino == be32_to_cpu(rec->file.FlNum);
305 default:
306 BUG();
307 return 1;
308 }
309 }
310
311 /*
312 * hfs_read_inode
313 */
hfs_read_inode(struct inode * inode,void * data)314 static int hfs_read_inode(struct inode *inode, void *data)
315 {
316 struct hfs_iget_data *idata = data;
317 struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
318 hfs_cat_rec *rec;
319
320 HFS_I(inode)->flags = 0;
321 HFS_I(inode)->rsrc_inode = NULL;
322 mutex_init(&HFS_I(inode)->extents_lock);
323 INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
324 spin_lock_init(&HFS_I(inode)->open_dir_lock);
325
326 /* Initialize the inode */
327 inode->i_uid = hsb->s_uid;
328 inode->i_gid = hsb->s_gid;
329 set_nlink(inode, 1);
330
331 if (idata->key)
332 HFS_I(inode)->cat_key = *idata->key;
333 else
334 HFS_I(inode)->flags |= HFS_FLG_RSRC;
335 HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
336
337 rec = idata->rec;
338 switch (rec->type) {
339 case HFS_CDR_FIL:
340 if (!HFS_IS_RSRC(inode)) {
341 hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
342 rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
343 } else {
344 hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
345 rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
346 }
347
348 inode->i_ino = be32_to_cpu(rec->file.FlNum);
349 inode->i_mode = S_IRUGO | S_IXUGO;
350 if (!(rec->file.Flags & HFS_FIL_LOCK))
351 inode->i_mode |= S_IWUGO;
352 inode->i_mode &= ~hsb->s_file_umask;
353 inode->i_mode |= S_IFREG;
354 inode->i_ctime = inode->i_atime = inode->i_mtime =
355 hfs_m_to_utime(rec->file.MdDat);
356 inode->i_op = &hfs_file_inode_operations;
357 inode->i_fop = &hfs_file_operations;
358 inode->i_mapping->a_ops = &hfs_aops;
359 break;
360 case HFS_CDR_DIR:
361 inode->i_ino = be32_to_cpu(rec->dir.DirID);
362 inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
363 HFS_I(inode)->fs_blocks = 0;
364 inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
365 inode->i_ctime = inode->i_atime = inode->i_mtime =
366 hfs_m_to_utime(rec->dir.MdDat);
367 inode->i_op = &hfs_dir_inode_operations;
368 inode->i_fop = &hfs_dir_operations;
369 break;
370 default:
371 make_bad_inode(inode);
372 }
373 return 0;
374 }
375
376 /*
377 * __hfs_iget()
378 *
379 * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
380 * the catalog B-tree and the 'type' of the desired file return the
381 * inode for that file/directory or NULL. Note that 'type' indicates
382 * whether we want the actual file or directory, or the corresponding
383 * metadata (AppleDouble header file or CAP metadata file).
384 */
hfs_iget(struct super_block * sb,struct hfs_cat_key * key,hfs_cat_rec * rec)385 struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
386 {
387 struct hfs_iget_data data = { key, rec };
388 struct inode *inode;
389 u32 cnid;
390
391 switch (rec->type) {
392 case HFS_CDR_DIR:
393 cnid = be32_to_cpu(rec->dir.DirID);
394 break;
395 case HFS_CDR_FIL:
396 cnid = be32_to_cpu(rec->file.FlNum);
397 break;
398 default:
399 return NULL;
400 }
401 inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
402 if (inode && (inode->i_state & I_NEW))
403 unlock_new_inode(inode);
404 return inode;
405 }
406
hfs_inode_write_fork(struct inode * inode,struct hfs_extent * ext,__be32 * log_size,__be32 * phys_size)407 void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
408 __be32 *log_size, __be32 *phys_size)
409 {
410 memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
411
412 if (log_size)
413 *log_size = cpu_to_be32(inode->i_size);
414 if (phys_size)
415 *phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
416 HFS_SB(inode->i_sb)->alloc_blksz);
417 }
418
hfs_write_inode(struct inode * inode,struct writeback_control * wbc)419 int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
420 {
421 struct inode *main_inode = inode;
422 struct hfs_find_data fd;
423 hfs_cat_rec rec;
424 int res;
425
426 hfs_dbg(INODE, "hfs_write_inode: %lu\n", inode->i_ino);
427 res = hfs_ext_write_extent(inode);
428 if (res)
429 return res;
430
431 if (inode->i_ino < HFS_FIRSTUSER_CNID) {
432 switch (inode->i_ino) {
433 case HFS_ROOT_CNID:
434 break;
435 case HFS_EXT_CNID:
436 hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
437 return 0;
438 case HFS_CAT_CNID:
439 hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
440 return 0;
441 default:
442 BUG();
443 return -EIO;
444 }
445 }
446
447 if (HFS_IS_RSRC(inode))
448 main_inode = HFS_I(inode)->rsrc_inode;
449
450 if (!main_inode->i_nlink)
451 return 0;
452
453 if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
454 /* panic? */
455 return -EIO;
456
457 fd.search_key->cat = HFS_I(main_inode)->cat_key;
458 if (hfs_brec_find(&fd))
459 /* panic? */
460 goto out;
461
462 if (S_ISDIR(main_inode->i_mode)) {
463 if (fd.entrylength < sizeof(struct hfs_cat_dir))
464 /* panic? */;
465 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
466 sizeof(struct hfs_cat_dir));
467 if (rec.type != HFS_CDR_DIR ||
468 be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
469 }
470
471 rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
472 rec.dir.Val = cpu_to_be16(inode->i_size - 2);
473
474 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
475 sizeof(struct hfs_cat_dir));
476 } else if (HFS_IS_RSRC(inode)) {
477 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
478 sizeof(struct hfs_cat_file));
479 hfs_inode_write_fork(inode, rec.file.RExtRec,
480 &rec.file.RLgLen, &rec.file.RPyLen);
481 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
482 sizeof(struct hfs_cat_file));
483 } else {
484 if (fd.entrylength < sizeof(struct hfs_cat_file))
485 /* panic? */;
486 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
487 sizeof(struct hfs_cat_file));
488 if (rec.type != HFS_CDR_FIL ||
489 be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
490 }
491
492 if (inode->i_mode & S_IWUSR)
493 rec.file.Flags &= ~HFS_FIL_LOCK;
494 else
495 rec.file.Flags |= HFS_FIL_LOCK;
496 hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
497 rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);
498
499 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
500 sizeof(struct hfs_cat_file));
501 }
502 out:
503 hfs_find_exit(&fd);
504 return 0;
505 }
506
hfs_file_lookup(struct inode * dir,struct dentry * dentry,unsigned int flags)507 static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
508 unsigned int flags)
509 {
510 struct inode *inode = NULL;
511 hfs_cat_rec rec;
512 struct hfs_find_data fd;
513 int res;
514
515 if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
516 goto out;
517
518 inode = HFS_I(dir)->rsrc_inode;
519 if (inode)
520 goto out;
521
522 inode = new_inode(dir->i_sb);
523 if (!inode)
524 return ERR_PTR(-ENOMEM);
525
526 res = hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
527 if (res) {
528 iput(inode);
529 return ERR_PTR(res);
530 }
531 fd.search_key->cat = HFS_I(dir)->cat_key;
532 res = hfs_brec_read(&fd, &rec, sizeof(rec));
533 if (!res) {
534 struct hfs_iget_data idata = { NULL, &rec };
535 hfs_read_inode(inode, &idata);
536 }
537 hfs_find_exit(&fd);
538 if (res) {
539 iput(inode);
540 return ERR_PTR(res);
541 }
542 HFS_I(inode)->rsrc_inode = dir;
543 HFS_I(dir)->rsrc_inode = inode;
544 igrab(dir);
545 inode_fake_hash(inode);
546 mark_inode_dirty(inode);
547 dont_mount(dentry);
548 out:
549 return d_splice_alias(inode, dentry);
550 }
551
hfs_evict_inode(struct inode * inode)552 void hfs_evict_inode(struct inode *inode)
553 {
554 truncate_inode_pages_final(&inode->i_data);
555 clear_inode(inode);
556 if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
557 HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
558 iput(HFS_I(inode)->rsrc_inode);
559 }
560 }
561
hfs_file_open(struct inode * inode,struct file * file)562 static int hfs_file_open(struct inode *inode, struct file *file)
563 {
564 if (HFS_IS_RSRC(inode))
565 inode = HFS_I(inode)->rsrc_inode;
566 atomic_inc(&HFS_I(inode)->opencnt);
567 return 0;
568 }
569
hfs_file_release(struct inode * inode,struct file * file)570 static int hfs_file_release(struct inode *inode, struct file *file)
571 {
572 //struct super_block *sb = inode->i_sb;
573
574 if (HFS_IS_RSRC(inode))
575 inode = HFS_I(inode)->rsrc_inode;
576 if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
577 inode_lock(inode);
578 hfs_file_truncate(inode);
579 //if (inode->i_flags & S_DEAD) {
580 // hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
581 // hfs_delete_inode(inode);
582 //}
583 inode_unlock(inode);
584 }
585 return 0;
586 }
587
588 /*
589 * hfs_notify_change()
590 *
591 * Based very closely on fs/msdos/inode.c by Werner Almesberger
592 *
593 * This is the notify_change() field in the super_operations structure
594 * for HFS file systems. The purpose is to take that changes made to
595 * an inode and apply then in a filesystem-dependent manner. In this
596 * case the process has a few of tasks to do:
597 * 1) prevent changes to the i_uid and i_gid fields.
598 * 2) map file permissions to the closest allowable permissions
599 * 3) Since multiple Linux files can share the same on-disk inode under
600 * HFS (for instance the data and resource forks of a file) a change
601 * to permissions must be applied to all other in-core inodes which
602 * correspond to the same HFS file.
603 */
604
hfs_inode_setattr(struct dentry * dentry,struct iattr * attr)605 int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
606 {
607 struct inode *inode = d_inode(dentry);
608 struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
609 int error;
610
611 error = setattr_prepare(dentry, attr); /* basic permission checks */
612 if (error)
613 return error;
614
615 /* no uig/gid changes and limit which mode bits can be set */
616 if (((attr->ia_valid & ATTR_UID) &&
617 (!uid_eq(attr->ia_uid, hsb->s_uid))) ||
618 ((attr->ia_valid & ATTR_GID) &&
619 (!gid_eq(attr->ia_gid, hsb->s_gid))) ||
620 ((attr->ia_valid & ATTR_MODE) &&
621 ((S_ISDIR(inode->i_mode) &&
622 (attr->ia_mode != inode->i_mode)) ||
623 (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
624 return hsb->s_quiet ? 0 : error;
625 }
626
627 if (attr->ia_valid & ATTR_MODE) {
628 /* Only the 'w' bits can ever change and only all together. */
629 if (attr->ia_mode & S_IWUSR)
630 attr->ia_mode = inode->i_mode | S_IWUGO;
631 else
632 attr->ia_mode = inode->i_mode & ~S_IWUGO;
633 attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
634 }
635
636 if ((attr->ia_valid & ATTR_SIZE) &&
637 attr->ia_size != i_size_read(inode)) {
638 inode_dio_wait(inode);
639
640 error = inode_newsize_ok(inode, attr->ia_size);
641 if (error)
642 return error;
643
644 truncate_setsize(inode, attr->ia_size);
645 hfs_file_truncate(inode);
646 inode->i_atime = inode->i_mtime = inode->i_ctime =
647 current_time(inode);
648 }
649
650 setattr_copy(inode, attr);
651 mark_inode_dirty(inode);
652 return 0;
653 }
654
hfs_file_fsync(struct file * filp,loff_t start,loff_t end,int datasync)655 static int hfs_file_fsync(struct file *filp, loff_t start, loff_t end,
656 int datasync)
657 {
658 struct inode *inode = filp->f_mapping->host;
659 struct super_block * sb;
660 int ret, err;
661
662 ret = file_write_and_wait_range(filp, start, end);
663 if (ret)
664 return ret;
665 inode_lock(inode);
666
667 /* sync the inode to buffers */
668 ret = write_inode_now(inode, 0);
669
670 /* sync the superblock to buffers */
671 sb = inode->i_sb;
672 flush_delayed_work(&HFS_SB(sb)->mdb_work);
673 /* .. finally sync the buffers to disk */
674 err = sync_blockdev(sb->s_bdev);
675 if (!ret)
676 ret = err;
677 inode_unlock(inode);
678 return ret;
679 }
680
681 static const struct file_operations hfs_file_operations = {
682 .llseek = generic_file_llseek,
683 .read_iter = generic_file_read_iter,
684 .write_iter = generic_file_write_iter,
685 .mmap = generic_file_mmap,
686 .splice_read = generic_file_splice_read,
687 .fsync = hfs_file_fsync,
688 .open = hfs_file_open,
689 .release = hfs_file_release,
690 };
691
692 static const struct inode_operations hfs_file_inode_operations = {
693 .lookup = hfs_file_lookup,
694 .setattr = hfs_inode_setattr,
695 .listxattr = generic_listxattr,
696 };
697
