xref: /openbmc/linux/fs/hfs/inode.c (revision 97da55fc)
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 
18 #include "hfs_fs.h"
19 #include "btree.h"
20 
21 static const struct file_operations hfs_file_operations;
22 static const struct inode_operations hfs_file_inode_operations;
23 
24 /*================ Variable-like macros ================*/
25 
26 #define HFS_VALID_MODE_BITS  (S_IFREG | S_IFDIR | S_IRWXUGO)
27 
28 static int hfs_writepage(struct page *page, struct writeback_control *wbc)
29 {
30 	return block_write_full_page(page, hfs_get_block, wbc);
31 }
32 
33 static int hfs_readpage(struct file *file, struct page *page)
34 {
35 	return block_read_full_page(page, hfs_get_block);
36 }
37 
38 static void hfs_write_failed(struct address_space *mapping, loff_t to)
39 {
40 	struct inode *inode = mapping->host;
41 
42 	if (to > inode->i_size) {
43 		truncate_pagecache(inode, to, inode->i_size);
44 		hfs_file_truncate(inode);
45 	}
46 }
47 
48 static int hfs_write_begin(struct file *file, struct address_space *mapping,
49 			loff_t pos, unsigned len, unsigned flags,
50 			struct page **pagep, void **fsdata)
51 {
52 	int ret;
53 
54 	*pagep = NULL;
55 	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
56 				hfs_get_block,
57 				&HFS_I(mapping->host)->phys_size);
58 	if (unlikely(ret))
59 		hfs_write_failed(mapping, pos + len);
60 
61 	return ret;
62 }
63 
64 static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
65 {
66 	return generic_block_bmap(mapping, block, hfs_get_block);
67 }
68 
69 static int hfs_releasepage(struct page *page, gfp_t mask)
70 {
71 	struct inode *inode = page->mapping->host;
72 	struct super_block *sb = inode->i_sb;
73 	struct hfs_btree *tree;
74 	struct hfs_bnode *node;
75 	u32 nidx;
76 	int i, res = 1;
77 
78 	switch (inode->i_ino) {
79 	case HFS_EXT_CNID:
80 		tree = HFS_SB(sb)->ext_tree;
81 		break;
82 	case HFS_CAT_CNID:
83 		tree = HFS_SB(sb)->cat_tree;
84 		break;
85 	default:
86 		BUG();
87 		return 0;
88 	}
89 
90 	if (!tree)
91 		return 0;
92 
93 	if (tree->node_size >= PAGE_CACHE_SIZE) {
94 		nidx = page->index >> (tree->node_size_shift - PAGE_CACHE_SHIFT);
95 		spin_lock(&tree->hash_lock);
96 		node = hfs_bnode_findhash(tree, nidx);
97 		if (!node)
98 			;
99 		else if (atomic_read(&node->refcnt))
100 			res = 0;
101 		if (res && node) {
102 			hfs_bnode_unhash(node);
103 			hfs_bnode_free(node);
104 		}
105 		spin_unlock(&tree->hash_lock);
106 	} else {
107 		nidx = page->index << (PAGE_CACHE_SHIFT - tree->node_size_shift);
108 		i = 1 << (PAGE_CACHE_SHIFT - tree->node_size_shift);
109 		spin_lock(&tree->hash_lock);
110 		do {
111 			node = hfs_bnode_findhash(tree, nidx++);
112 			if (!node)
113 				continue;
114 			if (atomic_read(&node->refcnt)) {
115 				res = 0;
116 				break;
117 			}
118 			hfs_bnode_unhash(node);
119 			hfs_bnode_free(node);
120 		} while (--i && nidx < tree->node_count);
121 		spin_unlock(&tree->hash_lock);
122 	}
123 	return res ? try_to_free_buffers(page) : 0;
124 }
125 
126 static ssize_t hfs_direct_IO(int rw, struct kiocb *iocb,
127 		const struct iovec *iov, loff_t offset, unsigned long nr_segs)
128 {
129 	struct file *file = iocb->ki_filp;
130 	struct address_space *mapping = file->f_mapping;
131 	struct inode *inode = file_inode(file)->i_mapping->host;
132 	ssize_t ret;
133 
134 	ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
135 				 hfs_get_block);
136 
137 	/*
138 	 * In case of error extending write may have instantiated a few
139 	 * blocks outside i_size. Trim these off again.
140 	 */
141 	if (unlikely((rw & WRITE) && ret < 0)) {
142 		loff_t isize = i_size_read(inode);
143 		loff_t end = offset + iov_length(iov, nr_segs);
144 
145 		if (end > isize)
146 			hfs_write_failed(mapping, end);
147 	}
148 
149 	return ret;
150 }
151 
152 static int hfs_writepages(struct address_space *mapping,
153 			  struct writeback_control *wbc)
154 {
155 	return mpage_writepages(mapping, wbc, hfs_get_block);
156 }
157 
158 const struct address_space_operations hfs_btree_aops = {
159 	.readpage	= hfs_readpage,
160 	.writepage	= hfs_writepage,
161 	.write_begin	= hfs_write_begin,
162 	.write_end	= generic_write_end,
163 	.bmap		= hfs_bmap,
164 	.releasepage	= hfs_releasepage,
165 };
166 
167 const struct address_space_operations hfs_aops = {
168 	.readpage	= hfs_readpage,
169 	.writepage	= hfs_writepage,
170 	.write_begin	= hfs_write_begin,
171 	.write_end	= generic_write_end,
172 	.bmap		= hfs_bmap,
173 	.direct_IO	= hfs_direct_IO,
174 	.writepages	= hfs_writepages,
175 };
176 
177 /*
178  * hfs_new_inode
179  */
180 struct inode *hfs_new_inode(struct inode *dir, struct qstr *name, umode_t mode)
181 {
182 	struct super_block *sb = dir->i_sb;
183 	struct inode *inode = new_inode(sb);
184 	if (!inode)
185 		return NULL;
186 
187 	mutex_init(&HFS_I(inode)->extents_lock);
188 	INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
189 	hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
190 	inode->i_ino = HFS_SB(sb)->next_id++;
191 	inode->i_mode = mode;
192 	inode->i_uid = current_fsuid();
193 	inode->i_gid = current_fsgid();
194 	set_nlink(inode, 1);
195 	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
196 	HFS_I(inode)->flags = 0;
197 	HFS_I(inode)->rsrc_inode = NULL;
198 	HFS_I(inode)->fs_blocks = 0;
199 	if (S_ISDIR(mode)) {
200 		inode->i_size = 2;
201 		HFS_SB(sb)->folder_count++;
202 		if (dir->i_ino == HFS_ROOT_CNID)
203 			HFS_SB(sb)->root_dirs++;
204 		inode->i_op = &hfs_dir_inode_operations;
205 		inode->i_fop = &hfs_dir_operations;
206 		inode->i_mode |= S_IRWXUGO;
207 		inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask;
208 	} else if (S_ISREG(mode)) {
209 		HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
210 		HFS_SB(sb)->file_count++;
211 		if (dir->i_ino == HFS_ROOT_CNID)
212 			HFS_SB(sb)->root_files++;
213 		inode->i_op = &hfs_file_inode_operations;
214 		inode->i_fop = &hfs_file_operations;
215 		inode->i_mapping->a_ops = &hfs_aops;
216 		inode->i_mode |= S_IRUGO|S_IXUGO;
217 		if (mode & S_IWUSR)
218 			inode->i_mode |= S_IWUGO;
219 		inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask;
220 		HFS_I(inode)->phys_size = 0;
221 		HFS_I(inode)->alloc_blocks = 0;
222 		HFS_I(inode)->first_blocks = 0;
223 		HFS_I(inode)->cached_start = 0;
224 		HFS_I(inode)->cached_blocks = 0;
225 		memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
226 		memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
227 	}
228 	insert_inode_hash(inode);
229 	mark_inode_dirty(inode);
230 	set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
231 	hfs_mark_mdb_dirty(sb);
232 
233 	return inode;
234 }
235 
236 void hfs_delete_inode(struct inode *inode)
237 {
238 	struct super_block *sb = inode->i_sb;
239 
240 	dprint(DBG_INODE, "delete_inode: %lu\n", inode->i_ino);
241 	if (S_ISDIR(inode->i_mode)) {
242 		HFS_SB(sb)->folder_count--;
243 		if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
244 			HFS_SB(sb)->root_dirs--;
245 		set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
246 		hfs_mark_mdb_dirty(sb);
247 		return;
248 	}
249 	HFS_SB(sb)->file_count--;
250 	if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
251 		HFS_SB(sb)->root_files--;
252 	if (S_ISREG(inode->i_mode)) {
253 		if (!inode->i_nlink) {
254 			inode->i_size = 0;
255 			hfs_file_truncate(inode);
256 		}
257 	}
258 	set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
259 	hfs_mark_mdb_dirty(sb);
260 }
261 
262 void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
263 			 __be32 __log_size, __be32 phys_size, u32 clump_size)
264 {
265 	struct super_block *sb = inode->i_sb;
266 	u32 log_size = be32_to_cpu(__log_size);
267 	u16 count;
268 	int i;
269 
270 	memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
271 	for (count = 0, i = 0; i < 3; i++)
272 		count += be16_to_cpu(ext[i].count);
273 	HFS_I(inode)->first_blocks = count;
274 
275 	inode->i_size = HFS_I(inode)->phys_size = log_size;
276 	HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
277 	inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits);
278 	HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
279 				     HFS_SB(sb)->alloc_blksz;
280 	HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
281 	if (!HFS_I(inode)->clump_blocks)
282 		HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
283 }
284 
285 struct hfs_iget_data {
286 	struct hfs_cat_key *key;
287 	hfs_cat_rec *rec;
288 };
289 
290 static int hfs_test_inode(struct inode *inode, void *data)
291 {
292 	struct hfs_iget_data *idata = data;
293 	hfs_cat_rec *rec;
294 
295 	rec = idata->rec;
296 	switch (rec->type) {
297 	case HFS_CDR_DIR:
298 		return inode->i_ino == be32_to_cpu(rec->dir.DirID);
299 	case HFS_CDR_FIL:
300 		return inode->i_ino == be32_to_cpu(rec->file.FlNum);
301 	default:
302 		BUG();
303 		return 1;
304 	}
305 }
306 
307 /*
308  * hfs_read_inode
309  */
310 static int hfs_read_inode(struct inode *inode, void *data)
311 {
312 	struct hfs_iget_data *idata = data;
313 	struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
314 	hfs_cat_rec *rec;
315 
316 	HFS_I(inode)->flags = 0;
317 	HFS_I(inode)->rsrc_inode = NULL;
318 	mutex_init(&HFS_I(inode)->extents_lock);
319 	INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
320 
321 	/* Initialize the inode */
322 	inode->i_uid = hsb->s_uid;
323 	inode->i_gid = hsb->s_gid;
324 	set_nlink(inode, 1);
325 
326 	if (idata->key)
327 		HFS_I(inode)->cat_key = *idata->key;
328 	else
329 		HFS_I(inode)->flags |= HFS_FLG_RSRC;
330 	HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
331 
332 	rec = idata->rec;
333 	switch (rec->type) {
334 	case HFS_CDR_FIL:
335 		if (!HFS_IS_RSRC(inode)) {
336 			hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
337 					    rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
338 		} else {
339 			hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
340 					    rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
341 		}
342 
343 		inode->i_ino = be32_to_cpu(rec->file.FlNum);
344 		inode->i_mode = S_IRUGO | S_IXUGO;
345 		if (!(rec->file.Flags & HFS_FIL_LOCK))
346 			inode->i_mode |= S_IWUGO;
347 		inode->i_mode &= ~hsb->s_file_umask;
348 		inode->i_mode |= S_IFREG;
349 		inode->i_ctime = inode->i_atime = inode->i_mtime =
350 				hfs_m_to_utime(rec->file.MdDat);
351 		inode->i_op = &hfs_file_inode_operations;
352 		inode->i_fop = &hfs_file_operations;
353 		inode->i_mapping->a_ops = &hfs_aops;
354 		break;
355 	case HFS_CDR_DIR:
356 		inode->i_ino = be32_to_cpu(rec->dir.DirID);
357 		inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
358 		HFS_I(inode)->fs_blocks = 0;
359 		inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
360 		inode->i_ctime = inode->i_atime = inode->i_mtime =
361 				hfs_m_to_utime(rec->dir.MdDat);
362 		inode->i_op = &hfs_dir_inode_operations;
363 		inode->i_fop = &hfs_dir_operations;
364 		break;
365 	default:
366 		make_bad_inode(inode);
367 	}
368 	return 0;
369 }
370 
371 /*
372  * __hfs_iget()
373  *
374  * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
375  * the catalog B-tree and the 'type' of the desired file return the
376  * inode for that file/directory or NULL.  Note that 'type' indicates
377  * whether we want the actual file or directory, or the corresponding
378  * metadata (AppleDouble header file or CAP metadata file).
379  */
380 struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
381 {
382 	struct hfs_iget_data data = { key, rec };
383 	struct inode *inode;
384 	u32 cnid;
385 
386 	switch (rec->type) {
387 	case HFS_CDR_DIR:
388 		cnid = be32_to_cpu(rec->dir.DirID);
389 		break;
390 	case HFS_CDR_FIL:
391 		cnid = be32_to_cpu(rec->file.FlNum);
392 		break;
393 	default:
394 		return NULL;
395 	}
396 	inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
397 	if (inode && (inode->i_state & I_NEW))
398 		unlock_new_inode(inode);
399 	return inode;
400 }
401 
402 void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
403 			  __be32 *log_size, __be32 *phys_size)
404 {
405 	memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
406 
407 	if (log_size)
408 		*log_size = cpu_to_be32(inode->i_size);
409 	if (phys_size)
410 		*phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
411 					 HFS_SB(inode->i_sb)->alloc_blksz);
412 }
413 
414 int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
415 {
416 	struct inode *main_inode = inode;
417 	struct hfs_find_data fd;
418 	hfs_cat_rec rec;
419 
420 	dprint(DBG_INODE, "hfs_write_inode: %lu\n", inode->i_ino);
421 	hfs_ext_write_extent(inode);
422 
423 	if (inode->i_ino < HFS_FIRSTUSER_CNID) {
424 		switch (inode->i_ino) {
425 		case HFS_ROOT_CNID:
426 			break;
427 		case HFS_EXT_CNID:
428 			hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
429 			return 0;
430 		case HFS_CAT_CNID:
431 			hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
432 			return 0;
433 		default:
434 			BUG();
435 			return -EIO;
436 		}
437 	}
438 
439 	if (HFS_IS_RSRC(inode))
440 		main_inode = HFS_I(inode)->rsrc_inode;
441 
442 	if (!main_inode->i_nlink)
443 		return 0;
444 
445 	if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
446 		/* panic? */
447 		return -EIO;
448 
449 	fd.search_key->cat = HFS_I(main_inode)->cat_key;
450 	if (hfs_brec_find(&fd))
451 		/* panic? */
452 		goto out;
453 
454 	if (S_ISDIR(main_inode->i_mode)) {
455 		if (fd.entrylength < sizeof(struct hfs_cat_dir))
456 			/* panic? */;
457 		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
458 			   sizeof(struct hfs_cat_dir));
459 		if (rec.type != HFS_CDR_DIR ||
460 		    be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
461 		}
462 
463 		rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
464 		rec.dir.Val = cpu_to_be16(inode->i_size - 2);
465 
466 		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
467 			    sizeof(struct hfs_cat_dir));
468 	} else if (HFS_IS_RSRC(inode)) {
469 		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
470 			       sizeof(struct hfs_cat_file));
471 		hfs_inode_write_fork(inode, rec.file.RExtRec,
472 				     &rec.file.RLgLen, &rec.file.RPyLen);
473 		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
474 				sizeof(struct hfs_cat_file));
475 	} else {
476 		if (fd.entrylength < sizeof(struct hfs_cat_file))
477 			/* panic? */;
478 		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
479 			   sizeof(struct hfs_cat_file));
480 		if (rec.type != HFS_CDR_FIL ||
481 		    be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
482 		}
483 
484 		if (inode->i_mode & S_IWUSR)
485 			rec.file.Flags &= ~HFS_FIL_LOCK;
486 		else
487 			rec.file.Flags |= HFS_FIL_LOCK;
488 		hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
489 		rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);
490 
491 		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
492 			    sizeof(struct hfs_cat_file));
493 	}
494 out:
495 	hfs_find_exit(&fd);
496 	return 0;
497 }
498 
499 static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
500 				      unsigned int flags)
501 {
502 	struct inode *inode = NULL;
503 	hfs_cat_rec rec;
504 	struct hfs_find_data fd;
505 	int res;
506 
507 	if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
508 		goto out;
509 
510 	inode = HFS_I(dir)->rsrc_inode;
511 	if (inode)
512 		goto out;
513 
514 	inode = new_inode(dir->i_sb);
515 	if (!inode)
516 		return ERR_PTR(-ENOMEM);
517 
518 	hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
519 	fd.search_key->cat = HFS_I(dir)->cat_key;
520 	res = hfs_brec_read(&fd, &rec, sizeof(rec));
521 	if (!res) {
522 		struct hfs_iget_data idata = { NULL, &rec };
523 		hfs_read_inode(inode, &idata);
524 	}
525 	hfs_find_exit(&fd);
526 	if (res) {
527 		iput(inode);
528 		return ERR_PTR(res);
529 	}
530 	HFS_I(inode)->rsrc_inode = dir;
531 	HFS_I(dir)->rsrc_inode = inode;
532 	igrab(dir);
533 	hlist_add_fake(&inode->i_hash);
534 	mark_inode_dirty(inode);
535 out:
536 	d_add(dentry, inode);
537 	return NULL;
538 }
539 
540 void hfs_evict_inode(struct inode *inode)
541 {
542 	truncate_inode_pages(&inode->i_data, 0);
543 	clear_inode(inode);
544 	if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
545 		HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
546 		iput(HFS_I(inode)->rsrc_inode);
547 	}
548 }
549 
550 static int hfs_file_open(struct inode *inode, struct file *file)
551 {
552 	if (HFS_IS_RSRC(inode))
553 		inode = HFS_I(inode)->rsrc_inode;
554 	atomic_inc(&HFS_I(inode)->opencnt);
555 	return 0;
556 }
557 
558 static int hfs_file_release(struct inode *inode, struct file *file)
559 {
560 	//struct super_block *sb = inode->i_sb;
561 
562 	if (HFS_IS_RSRC(inode))
563 		inode = HFS_I(inode)->rsrc_inode;
564 	if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
565 		mutex_lock(&inode->i_mutex);
566 		hfs_file_truncate(inode);
567 		//if (inode->i_flags & S_DEAD) {
568 		//	hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
569 		//	hfs_delete_inode(inode);
570 		//}
571 		mutex_unlock(&inode->i_mutex);
572 	}
573 	return 0;
574 }
575 
576 /*
577  * hfs_notify_change()
578  *
579  * Based very closely on fs/msdos/inode.c by Werner Almesberger
580  *
581  * This is the notify_change() field in the super_operations structure
582  * for HFS file systems.  The purpose is to take that changes made to
583  * an inode and apply then in a filesystem-dependent manner.  In this
584  * case the process has a few of tasks to do:
585  *  1) prevent changes to the i_uid and i_gid fields.
586  *  2) map file permissions to the closest allowable permissions
587  *  3) Since multiple Linux files can share the same on-disk inode under
588  *     HFS (for instance the data and resource forks of a file) a change
589  *     to permissions must be applied to all other in-core inodes which
590  *     correspond to the same HFS file.
591  */
592 
593 int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
594 {
595 	struct inode *inode = dentry->d_inode;
596 	struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
597 	int error;
598 
599 	error = inode_change_ok(inode, attr); /* basic permission checks */
600 	if (error)
601 		return error;
602 
603 	/* no uig/gid changes and limit which mode bits can be set */
604 	if (((attr->ia_valid & ATTR_UID) &&
605 	     (!uid_eq(attr->ia_uid, hsb->s_uid))) ||
606 	    ((attr->ia_valid & ATTR_GID) &&
607 	     (!gid_eq(attr->ia_gid, hsb->s_gid))) ||
608 	    ((attr->ia_valid & ATTR_MODE) &&
609 	     ((S_ISDIR(inode->i_mode) &&
610 	       (attr->ia_mode != inode->i_mode)) ||
611 	      (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
612 		return hsb->s_quiet ? 0 : error;
613 	}
614 
615 	if (attr->ia_valid & ATTR_MODE) {
616 		/* Only the 'w' bits can ever change and only all together. */
617 		if (attr->ia_mode & S_IWUSR)
618 			attr->ia_mode = inode->i_mode | S_IWUGO;
619 		else
620 			attr->ia_mode = inode->i_mode & ~S_IWUGO;
621 		attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
622 	}
623 
624 	if ((attr->ia_valid & ATTR_SIZE) &&
625 	    attr->ia_size != i_size_read(inode)) {
626 		inode_dio_wait(inode);
627 
628 		error = inode_newsize_ok(inode, attr->ia_size);
629 		if (error)
630 			return error;
631 
632 		truncate_setsize(inode, attr->ia_size);
633 		hfs_file_truncate(inode);
634 	}
635 
636 	setattr_copy(inode, attr);
637 	mark_inode_dirty(inode);
638 	return 0;
639 }
640 
641 static int hfs_file_fsync(struct file *filp, loff_t start, loff_t end,
642 			  int datasync)
643 {
644 	struct inode *inode = filp->f_mapping->host;
645 	struct super_block * sb;
646 	int ret, err;
647 
648 	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
649 	if (ret)
650 		return ret;
651 	mutex_lock(&inode->i_mutex);
652 
653 	/* sync the inode to buffers */
654 	ret = write_inode_now(inode, 0);
655 
656 	/* sync the superblock to buffers */
657 	sb = inode->i_sb;
658 	flush_delayed_work(&HFS_SB(sb)->mdb_work);
659 	/* .. finally sync the buffers to disk */
660 	err = sync_blockdev(sb->s_bdev);
661 	if (!ret)
662 		ret = err;
663 	mutex_unlock(&inode->i_mutex);
664 	return ret;
665 }
666 
667 static const struct file_operations hfs_file_operations = {
668 	.llseek		= generic_file_llseek,
669 	.read		= do_sync_read,
670 	.aio_read	= generic_file_aio_read,
671 	.write		= do_sync_write,
672 	.aio_write	= generic_file_aio_write,
673 	.mmap		= generic_file_mmap,
674 	.splice_read	= generic_file_splice_read,
675 	.fsync		= hfs_file_fsync,
676 	.open		= hfs_file_open,
677 	.release	= hfs_file_release,
678 };
679 
680 static const struct inode_operations hfs_file_inode_operations = {
681 	.lookup		= hfs_file_lookup,
682 	.setattr	= hfs_inode_setattr,
683 	.setxattr	= hfs_setxattr,
684 	.getxattr	= hfs_getxattr,
685 	.listxattr	= hfs_listxattr,
686 };
687