inode.c

  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
 25static const struct file_operations hfs_file_operations;
 26static 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
 32static int hfs_read_folio(struct file *file, struct folio *folio)
 33{
 34	return block_read_full_folio(folio, hfs_get_block);
 35}
 36
 37static void hfs_write_failed(struct address_space *mapping, loff_t to)
 38{
 39	struct inode *inode = mapping->host;
 40
 41	if (to > inode->i_size) {
 42		truncate_pagecache(inode, inode->i_size);
 43		hfs_file_truncate(inode);
 44	}
 45}
 46
 47int hfs_write_begin(const struct kiocb *iocb, struct address_space *mapping,
 48		    loff_t pos, unsigned int len, struct folio **foliop,
 49		    void **fsdata)
 50{
 51	int ret;
 52
 53	ret = cont_write_begin(iocb, mapping, pos, len, foliop, fsdata,
 54				hfs_get_block,
 55				&HFS_I(mapping->host)->phys_size);
 56	if (unlikely(ret))
 57		hfs_write_failed(mapping, pos + len);
 58
 59	return ret;
 60}
 61
 62static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
 63{
 64	return generic_block_bmap(mapping, block, hfs_get_block);
 65}
 66
 67static bool hfs_release_folio(struct folio *folio, gfp_t mask)
 68{
 69	struct inode *inode = folio->mapping->host;
 70	struct super_block *sb = inode->i_sb;
 71	struct hfs_btree *tree;
 72	struct hfs_bnode *node;
 73	u32 nidx;
 74	int i;
 75	bool res = true;
 76
 77	switch (inode->i_ino) {
 78	case HFS_EXT_CNID:
 79		tree = HFS_SB(sb)->ext_tree;
 80		break;
 81	case HFS_CAT_CNID:
 82		tree = HFS_SB(sb)->cat_tree;
 83		break;
 84	default:
 85		BUG();
 86		return false;
 87	}
 88
 89	if (!tree)
 90		return false;
 91
 92	if (tree->node_size >= PAGE_SIZE) {
 93		nidx = folio->index >> (tree->node_size_shift - PAGE_SHIFT);
 94		spin_lock(&tree->hash_lock);
 95		node = hfs_bnode_findhash(tree, nidx);
 96		if (!node)
 97			;
 98		else if (atomic_read(&node->refcnt))
 99			res = false;
100		if (res && node) {
101			hfs_bnode_unhash(node);
102			hfs_bnode_free(node);
103		}
104		spin_unlock(&tree->hash_lock);
105	} else {
106		nidx = folio->index << (PAGE_SHIFT - tree->node_size_shift);
107		i = 1 << (PAGE_SHIFT - tree->node_size_shift);
108		spin_lock(&tree->hash_lock);
109		do {
110			node = hfs_bnode_findhash(tree, nidx++);
111			if (!node)
112				continue;
113			if (atomic_read(&node->refcnt)) {
114				res = false;
115				break;
116			}
117			hfs_bnode_unhash(node);
118			hfs_bnode_free(node);
119		} while (--i && nidx < tree->node_count);
120		spin_unlock(&tree->hash_lock);
121	}
122	return res ? try_to_free_buffers(folio) : false;
123}
124
125static ssize_t hfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
126{
127	struct file *file = iocb->ki_filp;
128	struct address_space *mapping = file->f_mapping;
129	struct inode *inode = mapping->host;
130	size_t count = iov_iter_count(iter);
131	ssize_t ret;
132
133	ret = blockdev_direct_IO(iocb, inode, iter, hfs_get_block);
134
135	/*
136	 * In case of error extending write may have instantiated a few
137	 * blocks outside i_size. Trim these off again.
138	 */
139	if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) {
140		loff_t isize = i_size_read(inode);
141		loff_t end = iocb->ki_pos + count;
142
143		if (end > isize)
144			hfs_write_failed(mapping, end);
145	}
146
147	return ret;
148}
149
150static int hfs_writepages(struct address_space *mapping,
151			  struct writeback_control *wbc)
152{
153	return mpage_writepages(mapping, wbc, hfs_get_block);
154}
155
156const struct address_space_operations hfs_btree_aops = {
157	.dirty_folio	= block_dirty_folio,
158	.invalidate_folio = block_invalidate_folio,
159	.read_folio	= hfs_read_folio,
160	.writepages	= hfs_writepages,
161	.write_begin	= hfs_write_begin,
162	.write_end	= generic_write_end,
163	.migrate_folio	= buffer_migrate_folio,
164	.bmap		= hfs_bmap,
165	.release_folio	= hfs_release_folio,
166};
167
168const struct address_space_operations hfs_aops = {
169	.dirty_folio	= block_dirty_folio,
170	.invalidate_folio = block_invalidate_folio,
171	.read_folio	= hfs_read_folio,
172	.write_begin	= hfs_write_begin,
173	.write_end	= generic_write_end,
174	.bmap		= hfs_bmap,
175	.direct_IO	= hfs_direct_IO,
176	.writepages	= hfs_writepages,
177	.migrate_folio	= buffer_migrate_folio,
178};
179
180/*
181 * hfs_new_inode
182 */
183struct 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	s64 next_id;
188	s64 file_count;
189	s64 folder_count;
190	int err = -ENOMEM;
191
192	if (!inode)
193		goto out_err;
194
195	err = -ERANGE;
196
197	mutex_init(&HFS_I(inode)->extents_lock);
198	INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
199	spin_lock_init(&HFS_I(inode)->open_dir_lock);
200	hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
201	next_id = atomic64_inc_return(&HFS_SB(sb)->next_id);
202	if (next_id > U32_MAX) {
203		atomic64_dec(&HFS_SB(sb)->next_id);
204		pr_err("cannot create new inode: next CNID exceeds limit\n");
205		goto out_discard;
206	}
207	inode->i_ino = (u32)next_id;
208	inode->i_mode = mode;
209	inode->i_uid = current_fsuid();
210	inode->i_gid = current_fsgid();
211	set_nlink(inode, 1);
212	simple_inode_init_ts(inode);
213	HFS_I(inode)->flags = 0;
214	HFS_I(inode)->rsrc_inode = NULL;
215	HFS_I(inode)->fs_blocks = 0;
216	HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
217	if (S_ISDIR(mode)) {
218		inode->i_size = 2;
219		folder_count = atomic64_inc_return(&HFS_SB(sb)->folder_count);
220		if (folder_count> U32_MAX) {
221			atomic64_dec(&HFS_SB(sb)->folder_count);
222			pr_err("cannot create new inode: folder count exceeds limit\n");
223			goto out_discard;
224		}
225		if (dir->i_ino == HFS_ROOT_CNID)
226			HFS_SB(sb)->root_dirs++;
227		inode->i_op = &hfs_dir_inode_operations;
228		inode->i_fop = &hfs_dir_operations;
229		inode->i_mode |= S_IRWXUGO;
230		inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask;
231	} else if (S_ISREG(mode)) {
232		HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
233		file_count = atomic64_inc_return(&HFS_SB(sb)->file_count);
234		if (file_count > U32_MAX) {
235			atomic64_dec(&HFS_SB(sb)->file_count);
236			pr_err("cannot create new inode: file count exceeds limit\n");
237			goto out_discard;
238		}
239		if (dir->i_ino == HFS_ROOT_CNID)
240			HFS_SB(sb)->root_files++;
241		inode->i_op = &hfs_file_inode_operations;
242		inode->i_fop = &hfs_file_operations;
243		inode->i_mapping->a_ops = &hfs_aops;
244		inode->i_mode |= S_IRUGO|S_IXUGO;
245		if (mode & S_IWUSR)
246			inode->i_mode |= S_IWUGO;
247		inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask;
248		HFS_I(inode)->phys_size = 0;
249		HFS_I(inode)->alloc_blocks = 0;
250		HFS_I(inode)->first_blocks = 0;
251		HFS_I(inode)->cached_start = 0;
252		HFS_I(inode)->cached_blocks = 0;
253		memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
254		memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
255	}
256	insert_inode_hash(inode);
257	mark_inode_dirty(inode);
258	set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
259	hfs_mark_mdb_dirty(sb);
260
261	return inode;
262
263	out_discard:
264		iput(inode);
265	out_err:
266		return ERR_PTR(err);
267}
268
269void hfs_delete_inode(struct inode *inode)
270{
271	struct super_block *sb = inode->i_sb;
272
273	hfs_dbg("ino %lu\n", inode->i_ino);
274	if (S_ISDIR(inode->i_mode)) {
275		atomic64_dec(&HFS_SB(sb)->folder_count);
276		if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
277			HFS_SB(sb)->root_dirs--;
278		set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
279		hfs_mark_mdb_dirty(sb);
280		return;
281	}
282
283	atomic64_dec(&HFS_SB(sb)->file_count);
284	if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
285		HFS_SB(sb)->root_files--;
286	if (S_ISREG(inode->i_mode)) {
287		if (!inode->i_nlink) {
288			inode->i_size = 0;
289			hfs_file_truncate(inode);
290		}
291	}
292	set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
293	hfs_mark_mdb_dirty(sb);
294}
295
296void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
297			 __be32 __log_size, __be32 phys_size, u32 clump_size)
298{
299	struct super_block *sb = inode->i_sb;
300	u32 log_size = be32_to_cpu(__log_size);
301	u16 count;
302	int i;
303
304	memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
305	for (count = 0, i = 0; i < 3; i++)
306		count += be16_to_cpu(ext[i].count);
307	HFS_I(inode)->first_blocks = count;
308	HFS_I(inode)->cached_start = 0;
309	HFS_I(inode)->cached_blocks = 0;
310
311	inode->i_size = HFS_I(inode)->phys_size = log_size;
312	HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
313	inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits);
314	HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
315				     HFS_SB(sb)->alloc_blksz;
316	HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
317	if (!HFS_I(inode)->clump_blocks)
318		HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
319}
320
321struct hfs_iget_data {
322	struct hfs_cat_key *key;
323	hfs_cat_rec *rec;
324};
325
326static int hfs_test_inode(struct inode *inode, void *data)
327{
328	struct hfs_iget_data *idata = data;
329	hfs_cat_rec *rec;
330
331	rec = idata->rec;
332	switch (rec->type) {
333	case HFS_CDR_DIR:
334		return inode->i_ino == be32_to_cpu(rec->dir.DirID);
335	case HFS_CDR_FIL:
336		return inode->i_ino == be32_to_cpu(rec->file.FlNum);
337	default:
338		BUG();
339		return 1;
340	}
341}
342
343/*
344 * hfs_read_inode
345 */
346static int hfs_read_inode(struct inode *inode, void *data)
347{
348	struct hfs_iget_data *idata = data;
349	struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
350	hfs_cat_rec *rec;
351
352	HFS_I(inode)->flags = 0;
353	HFS_I(inode)->rsrc_inode = NULL;
354	mutex_init(&HFS_I(inode)->extents_lock);
355	INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
356	spin_lock_init(&HFS_I(inode)->open_dir_lock);
357
358	/* Initialize the inode */
359	inode->i_uid = hsb->s_uid;
360	inode->i_gid = hsb->s_gid;
361	set_nlink(inode, 1);
362
363	if (idata->key)
364		HFS_I(inode)->cat_key = *idata->key;
365	else
366		HFS_I(inode)->flags |= HFS_FLG_RSRC;
367	HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
368
369	rec = idata->rec;
370	switch (rec->type) {
371	case HFS_CDR_FIL:
372		if (!HFS_IS_RSRC(inode)) {
373			hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
374					    rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
375		} else {
376			hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
377					    rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
378		}
379
380		inode->i_ino = be32_to_cpu(rec->file.FlNum);
381		inode->i_mode = S_IRUGO | S_IXUGO;
382		if (!(rec->file.Flags & HFS_FIL_LOCK))
383			inode->i_mode |= S_IWUGO;
384		inode->i_mode &= ~hsb->s_file_umask;
385		inode->i_mode |= S_IFREG;
386		inode_set_mtime_to_ts(inode,
387				      inode_set_atime_to_ts(inode, inode_set_ctime_to_ts(inode, hfs_m_to_utime(rec->file.MdDat))));
388		inode->i_op = &hfs_file_inode_operations;
389		inode->i_fop = &hfs_file_operations;
390		inode->i_mapping->a_ops = &hfs_aops;
391		break;
392	case HFS_CDR_DIR:
393		inode->i_ino = be32_to_cpu(rec->dir.DirID);
394		inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
395		HFS_I(inode)->fs_blocks = 0;
396		inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
397		inode_set_mtime_to_ts(inode,
398				      inode_set_atime_to_ts(inode, inode_set_ctime_to_ts(inode, hfs_m_to_utime(rec->dir.MdDat))));
399		inode->i_op = &hfs_dir_inode_operations;
400		inode->i_fop = &hfs_dir_operations;
401		break;
402	default:
403		make_bad_inode(inode);
404	}
405	return 0;
406}
407
408/*
409 * __hfs_iget()
410 *
411 * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
412 * the catalog B-tree and the 'type' of the desired file return the
413 * inode for that file/directory or NULL.  Note that 'type' indicates
414 * whether we want the actual file or directory, or the corresponding
415 * metadata (AppleDouble header file or CAP metadata file).
416 */
417struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
418{
419	struct hfs_iget_data data = { key, rec };
420	struct inode *inode;
421	u32 cnid;
422
423	switch (rec->type) {
424	case HFS_CDR_DIR:
425		cnid = be32_to_cpu(rec->dir.DirID);
426		break;
427	case HFS_CDR_FIL:
428		cnid = be32_to_cpu(rec->file.FlNum);
429		break;
430	default:
431		return NULL;
432	}
433	inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
434	if (inode && (inode_state_read_once(inode) & I_NEW))
435		unlock_new_inode(inode);
436	return inode;
437}
438
439void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
440			  __be32 *log_size, __be32 *phys_size)
441{
442	memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
443
444	if (log_size)
445		*log_size = cpu_to_be32(inode->i_size);
446	if (phys_size)
447		*phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
448					 HFS_SB(inode->i_sb)->alloc_blksz);
449}
450
451int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
452{
453	struct inode *main_inode = inode;
454	struct hfs_find_data fd;
455	hfs_cat_rec rec;
456	int res;
457
458	hfs_dbg("ino %lu\n", inode->i_ino);
459	res = hfs_ext_write_extent(inode);
460	if (res)
461		return res;
462
463	if (inode->i_ino < HFS_FIRSTUSER_CNID) {
464		switch (inode->i_ino) {
465		case HFS_ROOT_CNID:
466			break;
467		case HFS_EXT_CNID:
468			hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
469			return 0;
470		case HFS_CAT_CNID:
471			hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
472			return 0;
473		default:
474			BUG();
475			return -EIO;
476		}
477	}
478
479	if (HFS_IS_RSRC(inode))
480		main_inode = HFS_I(inode)->rsrc_inode;
481
482	if (!main_inode->i_nlink)
483		return 0;
484
485	if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
486		/* panic? */
487		return -EIO;
488
489	res = -EIO;
490	if (HFS_I(main_inode)->cat_key.CName.len > HFS_NAMELEN)
491		goto out;
492	fd.search_key->cat = HFS_I(main_inode)->cat_key;
493	if (hfs_brec_find(&fd))
494		goto out;
495
496	if (S_ISDIR(main_inode->i_mode)) {
497		if (fd.entrylength < sizeof(struct hfs_cat_dir))
498			goto out;
499		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
500			   sizeof(struct hfs_cat_dir));
501		if (rec.type != HFS_CDR_DIR ||
502		    be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
503		}
504
505		rec.dir.MdDat = hfs_u_to_mtime(inode_get_mtime(inode));
506		rec.dir.Val = cpu_to_be16(inode->i_size - 2);
507
508		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
509			    sizeof(struct hfs_cat_dir));
510	} else if (HFS_IS_RSRC(inode)) {
511		if (fd.entrylength < sizeof(struct hfs_cat_file))
512			goto out;
513		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
514			       sizeof(struct hfs_cat_file));
515		hfs_inode_write_fork(inode, rec.file.RExtRec,
516				     &rec.file.RLgLen, &rec.file.RPyLen);
517		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
518				sizeof(struct hfs_cat_file));
519	} else {
520		if (fd.entrylength < sizeof(struct hfs_cat_file))
521			goto out;
522		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
523			   sizeof(struct hfs_cat_file));
524		if (rec.type != HFS_CDR_FIL ||
525		    be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
526		}
527
528		if (inode->i_mode & S_IWUSR)
529			rec.file.Flags &= ~HFS_FIL_LOCK;
530		else
531			rec.file.Flags |= HFS_FIL_LOCK;
532		hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
533		rec.file.MdDat = hfs_u_to_mtime(inode_get_mtime(inode));
534
535		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
536			    sizeof(struct hfs_cat_file));
537	}
538	res = 0;
539out:
540	hfs_find_exit(&fd);
541	return res;
542}
543
544static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
545				      unsigned int flags)
546{
547	struct inode *inode = NULL;
548	hfs_cat_rec rec;
549	struct hfs_find_data fd;
550	int res;
551
552	if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
553		goto out;
554
555	inode = HFS_I(dir)->rsrc_inode;
556	if (inode)
557		goto out;
558
559	inode = new_inode(dir->i_sb);
560	if (!inode)
561		return ERR_PTR(-ENOMEM);
562
563	res = hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
564	if (res) {
565		iput(inode);
566		return ERR_PTR(res);
567	}
568	fd.search_key->cat = HFS_I(dir)->cat_key;
569	res = hfs_brec_read(&fd, &rec, sizeof(rec));
570	if (!res) {
571		struct hfs_iget_data idata = { NULL, &rec };
572		hfs_read_inode(inode, &idata);
573	}
574	hfs_find_exit(&fd);
575	if (res) {
576		iput(inode);
577		return ERR_PTR(res);
578	}
579	HFS_I(inode)->rsrc_inode = dir;
580	HFS_I(dir)->rsrc_inode = inode;
581	igrab(dir);
582	inode_fake_hash(inode);
583	mark_inode_dirty(inode);
584	dont_mount(dentry);
585out:
586	return d_splice_alias(inode, dentry);
587}
588
589void hfs_evict_inode(struct inode *inode)
590{
591	truncate_inode_pages_final(&inode->i_data);
592	clear_inode(inode);
593	if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
594		HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
595		iput(HFS_I(inode)->rsrc_inode);
596	}
597}
598
599static int hfs_file_open(struct inode *inode, struct file *file)
600{
601	if (HFS_IS_RSRC(inode))
602		inode = HFS_I(inode)->rsrc_inode;
603	atomic_inc(&HFS_I(inode)->opencnt);
604	return 0;
605}
606
607static int hfs_file_release(struct inode *inode, struct file *file)
608{
609	//struct super_block *sb = inode->i_sb;
610
611	if (HFS_IS_RSRC(inode))
612		inode = HFS_I(inode)->rsrc_inode;
613	if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
614		inode_lock(inode);
615		hfs_file_truncate(inode);
616		//if (inode->i_flags & S_DEAD) {
617		//	hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
618		//	hfs_delete_inode(inode);
619		//}
620		inode_unlock(inode);
621	}
622	return 0;
623}
624
625/*
626 * hfs_notify_change()
627 *
628 * Based very closely on fs/msdos/inode.c by Werner Almesberger
629 *
630 * This is the notify_change() field in the super_operations structure
631 * for HFS file systems.  The purpose is to take that changes made to
632 * an inode and apply then in a filesystem-dependent manner.  In this
633 * case the process has a few of tasks to do:
634 *  1) prevent changes to the i_uid and i_gid fields.
635 *  2) map file permissions to the closest allowable permissions
636 *  3) Since multiple Linux files can share the same on-disk inode under
637 *     HFS (for instance the data and resource forks of a file) a change
638 *     to permissions must be applied to all other in-core inodes which
639 *     correspond to the same HFS file.
640 */
641
642int hfs_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
643		      struct iattr *attr)
644{
645	struct inode *inode = d_inode(dentry);
646	struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
647	int error;
648
649	error = setattr_prepare(&nop_mnt_idmap, dentry,
650				attr); /* basic permission checks */
651	if (error)
652		return error;
653
654	/* no uig/gid changes and limit which mode bits can be set */
655	if (((attr->ia_valid & ATTR_UID) &&
656	     (!uid_eq(attr->ia_uid, hsb->s_uid))) ||
657	    ((attr->ia_valid & ATTR_GID) &&
658	     (!gid_eq(attr->ia_gid, hsb->s_gid))) ||
659	    ((attr->ia_valid & ATTR_MODE) &&
660	     ((S_ISDIR(inode->i_mode) &&
661	       (attr->ia_mode != inode->i_mode)) ||
662	      (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
663		return hsb->s_quiet ? 0 : error;
664	}
665
666	if (attr->ia_valid & ATTR_MODE) {
667		/* Only the 'w' bits can ever change and only all together. */
668		if (attr->ia_mode & S_IWUSR)
669			attr->ia_mode = inode->i_mode | S_IWUGO;
670		else
671			attr->ia_mode = inode->i_mode & ~S_IWUGO;
672		attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
673	}
674
675	if ((attr->ia_valid & ATTR_SIZE) &&
676	    attr->ia_size != i_size_read(inode)) {
677		inode_dio_wait(inode);
678
679		error = inode_newsize_ok(inode, attr->ia_size);
680		if (error)
681			return error;
682
683		truncate_setsize(inode, attr->ia_size);
684		hfs_file_truncate(inode);
685		simple_inode_init_ts(inode);
686	}
687
688	setattr_copy(&nop_mnt_idmap, inode, attr);
689	mark_inode_dirty(inode);
690	return 0;
691}
692
693static int hfs_file_fsync(struct file *filp, loff_t start, loff_t end,
694			  int datasync)
695{
696	struct inode *inode = filp->f_mapping->host;
697	struct super_block * sb;
698	int ret, err;
699
700	ret = file_write_and_wait_range(filp, start, end);
701	if (ret)
702		return ret;
703	inode_lock(inode);
704
705	/* sync the inode to buffers */
706	ret = write_inode_now(inode, 0);
707
708	/* sync the superblock to buffers */
709	sb = inode->i_sb;
710	flush_delayed_work(&HFS_SB(sb)->mdb_work);
711	/* .. finally sync the buffers to disk */
712	err = sync_blockdev(sb->s_bdev);
713	if (!ret)
714		ret = err;
715	inode_unlock(inode);
716	return ret;
717}
718
719static const struct file_operations hfs_file_operations = {
720	.llseek		= generic_file_llseek,
721	.read_iter	= generic_file_read_iter,
722	.write_iter	= generic_file_write_iter,
723	.mmap_prepare	= generic_file_mmap_prepare,
724	.splice_read	= filemap_splice_read,
725	.splice_write	= iter_file_splice_write,
726	.fsync		= hfs_file_fsync,
727	.open		= hfs_file_open,
728	.release	= hfs_file_release,
729};
730
731static const struct inode_operations hfs_file_inode_operations = {
732	.lookup		= hfs_file_lookup,
733	.setattr	= hfs_inode_setattr,
734	.listxattr	= generic_listxattr,
735};