namei.c revision 5a20d339c785d98d8b050b9afc098e4184a6098c 
1/*
2 * fs/f2fs/namei.c
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 *             http://www.samsung.com/
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/fs.h>
12#include <linux/f2fs_fs.h>
13#include <linux/pagemap.h>
14#include <linux/sched.h>
15#include <linux/ctype.h>
16
17#include "f2fs.h"
18#include "xattr.h"
19#include "acl.h"
20
21static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
22{
23	struct super_block *sb = dir->i_sb;
24	struct f2fs_sb_info *sbi = F2FS_SB(sb);
25	nid_t ino;
26	struct inode *inode;
27	bool nid_free = false;
28	int err;
29
30	inode = new_inode(sb);
31	if (!inode)
32		return ERR_PTR(-ENOMEM);
33
34	mutex_lock_op(sbi, NODE_NEW);
35	if (!alloc_nid(sbi, &ino)) {
36		mutex_unlock_op(sbi, NODE_NEW);
37		err = -ENOSPC;
38		goto fail;
39	}
40	mutex_unlock_op(sbi, NODE_NEW);
41
42	inode->i_uid = current_fsuid();
43
44	if (dir->i_mode & S_ISGID) {
45		inode->i_gid = dir->i_gid;
46		if (S_ISDIR(mode))
47			mode |= S_ISGID;
48	} else {
49		inode->i_gid = current_fsgid();
50	}
51
52	inode->i_ino = ino;
53	inode->i_mode = mode;
54	inode->i_blocks = 0;
55	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
56	inode->i_generation = sbi->s_next_generation++;
57
58	err = insert_inode_locked(inode);
59	if (err) {
60		err = -EINVAL;
61		nid_free = true;
62		goto out;
63	}
64
65	mark_inode_dirty(inode);
66	return inode;
67
68out:
69	clear_nlink(inode);
70	unlock_new_inode(inode);
71fail:
72	iput(inode);
73	if (nid_free)
74		alloc_nid_failed(sbi, ino);
75	return ERR_PTR(err);
76}
77
78static int is_multimedia_file(const unsigned char *s, const char *sub)
79{
80	size_t slen = strlen(s);
81	size_t sublen = strlen(sub);
82	int ret;
83
84	if (sublen > slen)
85		return 1;
86
87	ret = memcmp(s + slen - sublen, sub, sublen);
88	if (ret) {	/* compare upper case */
89		int i;
90		char upper_sub[8];
91		for (i = 0; i < sublen && i < sizeof(upper_sub); i++)
92			upper_sub[i] = toupper(sub[i]);
93		return memcmp(s + slen - sublen, upper_sub, sublen);
94	}
95
96	return ret;
97}
98
99/*
100 * Set multimedia files as cold files for hot/cold data separation
101 */
102static inline void set_cold_file(struct f2fs_sb_info *sbi, struct inode *inode,
103		const unsigned char *name)
104{
105	int i;
106	__u8 (*extlist)[8] = sbi->raw_super->extension_list;
107
108	int count = le32_to_cpu(sbi->raw_super->extension_count);
109	for (i = 0; i < count; i++) {
110		if (!is_multimedia_file(name, extlist[i])) {
111			F2FS_I(inode)->i_advise |= FADVISE_COLD_BIT;
112			break;
113		}
114	}
115}
116
117static int f2fs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
118						bool excl)
119{
120	struct super_block *sb = dir->i_sb;
121	struct f2fs_sb_info *sbi = F2FS_SB(sb);
122	struct inode *inode;
123	nid_t ino = 0;
124	int err;
125
126	f2fs_balance_fs(sbi);
127
128	inode = f2fs_new_inode(dir, mode);
129	if (IS_ERR(inode))
130		return PTR_ERR(inode);
131
132	if (!test_opt(sbi, DISABLE_EXT_IDENTIFY))
133		set_cold_file(sbi, inode, dentry->d_name.name);
134
135	inode->i_op = &f2fs_file_inode_operations;
136	inode->i_fop = &f2fs_file_operations;
137	inode->i_mapping->a_ops = &f2fs_dblock_aops;
138	ino = inode->i_ino;
139
140	err = f2fs_add_link(dentry, inode);
141	if (err)
142		goto out;
143
144	alloc_nid_done(sbi, ino);
145
146	if (!sbi->por_doing)
147		d_instantiate(dentry, inode);
148	unlock_new_inode(inode);
149	return 0;
150out:
151	clear_nlink(inode);
152	unlock_new_inode(inode);
153	iput(inode);
154	alloc_nid_failed(sbi, ino);
155	return err;
156}
157
158static int f2fs_link(struct dentry *old_dentry, struct inode *dir,
159		struct dentry *dentry)
160{
161	struct inode *inode = old_dentry->d_inode;
162	struct super_block *sb = dir->i_sb;
163	struct f2fs_sb_info *sbi = F2FS_SB(sb);
164	int err;
165
166	f2fs_balance_fs(sbi);
167
168	inode->i_ctime = CURRENT_TIME;
169	atomic_inc(&inode->i_count);
170
171	set_inode_flag(F2FS_I(inode), FI_INC_LINK);
172	err = f2fs_add_link(dentry, inode);
173	if (err)
174		goto out;
175
176	d_instantiate(dentry, inode);
177	return 0;
178out:
179	clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
180	iput(inode);
181	return err;
182}
183
184struct dentry *f2fs_get_parent(struct dentry *child)
185{
186	struct qstr dotdot = QSTR_INIT("..", 2);
187	unsigned long ino = f2fs_inode_by_name(child->d_inode, &dotdot);
188	if (!ino)
189		return ERR_PTR(-ENOENT);
190	return d_obtain_alias(f2fs_iget(child->d_inode->i_sb, ino));
191}
192
193static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
194		unsigned int flags)
195{
196	struct inode *inode = NULL;
197	struct f2fs_dir_entry *de;
198	struct page *page;
199
200	if (dentry->d_name.len > F2FS_NAME_LEN)
201		return ERR_PTR(-ENAMETOOLONG);
202
203	de = f2fs_find_entry(dir, &dentry->d_name, &page);
204	if (de) {
205		nid_t ino = le32_to_cpu(de->ino);
206		kunmap(page);
207		f2fs_put_page(page, 0);
208
209		inode = f2fs_iget(dir->i_sb, ino);
210		if (IS_ERR(inode))
211			return ERR_CAST(inode);
212	}
213
214	return d_splice_alias(inode, dentry);
215}
216
217static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
218{
219	struct super_block *sb = dir->i_sb;
220	struct f2fs_sb_info *sbi = F2FS_SB(sb);
221	struct inode *inode = dentry->d_inode;
222	struct f2fs_dir_entry *de;
223	struct page *page;
224	int err = -ENOENT;
225
226	f2fs_balance_fs(sbi);
227
228	de = f2fs_find_entry(dir, &dentry->d_name, &page);
229	if (!de)
230		goto fail;
231
232	err = check_orphan_space(sbi);
233	if (err) {
234		kunmap(page);
235		f2fs_put_page(page, 0);
236		goto fail;
237	}
238
239	f2fs_delete_entry(de, page, inode);
240
241	/* In order to evict this inode,  we set it dirty */
242	mark_inode_dirty(inode);
243fail:
244	return err;
245}
246
247static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
248					const char *symname)
249{
250	struct super_block *sb = dir->i_sb;
251	struct f2fs_sb_info *sbi = F2FS_SB(sb);
252	struct inode *inode;
253	size_t symlen = strlen(symname) + 1;
254	int err;
255
256	f2fs_balance_fs(sbi);
257
258	inode = f2fs_new_inode(dir, S_IFLNK | S_IRWXUGO);
259	if (IS_ERR(inode))
260		return PTR_ERR(inode);
261
262	inode->i_op = &f2fs_symlink_inode_operations;
263	inode->i_mapping->a_ops = &f2fs_dblock_aops;
264
265	err = f2fs_add_link(dentry, inode);
266	if (err)
267		goto out;
268
269	err = page_symlink(inode, symname, symlen);
270	alloc_nid_done(sbi, inode->i_ino);
271
272	d_instantiate(dentry, inode);
273	unlock_new_inode(inode);
274	return err;
275out:
276	clear_nlink(inode);
277	unlock_new_inode(inode);
278	iput(inode);
279	alloc_nid_failed(sbi, inode->i_ino);
280	return err;
281}
282
283static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
284{
285	struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
286	struct inode *inode;
287	int err;
288
289	f2fs_balance_fs(sbi);
290
291	inode = f2fs_new_inode(dir, S_IFDIR | mode);
292	if (IS_ERR(inode))
293		return PTR_ERR(inode);
294
295	inode->i_op = &f2fs_dir_inode_operations;
296	inode->i_fop = &f2fs_dir_operations;
297	inode->i_mapping->a_ops = &f2fs_dblock_aops;
298	mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_ZERO);
299
300	set_inode_flag(F2FS_I(inode), FI_INC_LINK);
301	err = f2fs_add_link(dentry, inode);
302	if (err)
303		goto out_fail;
304
305	alloc_nid_done(sbi, inode->i_ino);
306
307	d_instantiate(dentry, inode);
308	unlock_new_inode(inode);
309
310	return 0;
311
312out_fail:
313	clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
314	clear_nlink(inode);
315	unlock_new_inode(inode);
316	iput(inode);
317	alloc_nid_failed(sbi, inode->i_ino);
318	return err;
319}
320
321static int f2fs_rmdir(struct inode *dir, struct dentry *dentry)
322{
323	struct inode *inode = dentry->d_inode;
324	if (f2fs_empty_dir(inode))
325		return f2fs_unlink(dir, dentry);
326	return -ENOTEMPTY;
327}
328
329static int f2fs_mknod(struct inode *dir, struct dentry *dentry,
330				umode_t mode, dev_t rdev)
331{
332	struct super_block *sb = dir->i_sb;
333	struct f2fs_sb_info *sbi = F2FS_SB(sb);
334	struct inode *inode;
335	int err = 0;
336
337	if (!new_valid_dev(rdev))
338		return -EINVAL;
339
340	f2fs_balance_fs(sbi);
341
342	inode = f2fs_new_inode(dir, mode);
343	if (IS_ERR(inode))
344		return PTR_ERR(inode);
345
346	init_special_inode(inode, inode->i_mode, rdev);
347	inode->i_op = &f2fs_special_inode_operations;
348
349	err = f2fs_add_link(dentry, inode);
350	if (err)
351		goto out;
352
353	alloc_nid_done(sbi, inode->i_ino);
354	d_instantiate(dentry, inode);
355	unlock_new_inode(inode);
356	return 0;
357out:
358	clear_nlink(inode);
359	unlock_new_inode(inode);
360	iput(inode);
361	alloc_nid_failed(sbi, inode->i_ino);
362	return err;
363}
364
365static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
366			struct inode *new_dir, struct dentry *new_dentry)
367{
368	struct super_block *sb = old_dir->i_sb;
369	struct f2fs_sb_info *sbi = F2FS_SB(sb);
370	struct inode *old_inode = old_dentry->d_inode;
371	struct inode *new_inode = new_dentry->d_inode;
372	struct page *old_dir_page;
373	struct page *old_page;
374	struct f2fs_dir_entry *old_dir_entry = NULL;
375	struct f2fs_dir_entry *old_entry;
376	struct f2fs_dir_entry *new_entry;
377	int err = -ENOENT;
378
379	f2fs_balance_fs(sbi);
380
381	old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
382	if (!old_entry)
383		goto out;
384
385	if (S_ISDIR(old_inode->i_mode)) {
386		err = -EIO;
387		old_dir_entry = f2fs_parent_dir(old_inode, &old_dir_page);
388		if (!old_dir_entry)
389			goto out_old;
390	}
391
392	mutex_lock_op(sbi, RENAME);
393
394	if (new_inode) {
395		struct page *new_page;
396
397		err = -ENOTEMPTY;
398		if (old_dir_entry && !f2fs_empty_dir(new_inode))
399			goto out_dir;
400
401		err = -ENOENT;
402		new_entry = f2fs_find_entry(new_dir, &new_dentry->d_name,
403						&new_page);
404		if (!new_entry)
405			goto out_dir;
406
407		f2fs_set_link(new_dir, new_entry, new_page, old_inode);
408
409		new_inode->i_ctime = CURRENT_TIME;
410		if (old_dir_entry)
411			drop_nlink(new_inode);
412		drop_nlink(new_inode);
413		if (!new_inode->i_nlink)
414			add_orphan_inode(sbi, new_inode->i_ino);
415		f2fs_write_inode(new_inode, NULL);
416	} else {
417		err = f2fs_add_link(new_dentry, old_inode);
418		if (err)
419			goto out_dir;
420
421		if (old_dir_entry) {
422			inc_nlink(new_dir);
423			f2fs_write_inode(new_dir, NULL);
424		}
425	}
426
427	old_inode->i_ctime = CURRENT_TIME;
428	set_inode_flag(F2FS_I(old_inode), FI_NEED_CP);
429	mark_inode_dirty(old_inode);
430
431	f2fs_delete_entry(old_entry, old_page, NULL);
432
433	if (old_dir_entry) {
434		if (old_dir != new_dir) {
435			f2fs_set_link(old_inode, old_dir_entry,
436						old_dir_page, new_dir);
437		} else {
438			kunmap(old_dir_page);
439			f2fs_put_page(old_dir_page, 0);
440		}
441		drop_nlink(old_dir);
442		f2fs_write_inode(old_dir, NULL);
443	}
444
445	mutex_unlock_op(sbi, RENAME);
446	return 0;
447
448out_dir:
449	if (old_dir_entry) {
450		kunmap(old_dir_page);
451		f2fs_put_page(old_dir_page, 0);
452	}
453	mutex_unlock_op(sbi, RENAME);
454out_old:
455	kunmap(old_page);
456	f2fs_put_page(old_page, 0);
457out:
458	return err;
459}
460
461const struct inode_operations f2fs_dir_inode_operations = {
462	.create		= f2fs_create,
463	.lookup		= f2fs_lookup,
464	.link		= f2fs_link,
465	.unlink		= f2fs_unlink,
466	.symlink	= f2fs_symlink,
467	.mkdir		= f2fs_mkdir,
468	.rmdir		= f2fs_rmdir,
469	.mknod		= f2fs_mknod,
470	.rename		= f2fs_rename,
471	.setattr	= f2fs_setattr,
472	.get_acl	= f2fs_get_acl,
473#ifdef CONFIG_F2FS_FS_XATTR
474	.setxattr	= generic_setxattr,
475	.getxattr	= generic_getxattr,
476	.listxattr	= f2fs_listxattr,
477	.removexattr	= generic_removexattr,
478#endif
479};
480
481const struct inode_operations f2fs_symlink_inode_operations = {
482	.readlink       = generic_readlink,
483	.follow_link    = page_follow_link_light,
484	.put_link       = page_put_link,
485	.setattr	= f2fs_setattr,
486#ifdef CONFIG_F2FS_FS_XATTR
487	.setxattr	= generic_setxattr,
488	.getxattr	= generic_getxattr,
489	.listxattr	= f2fs_listxattr,
490	.removexattr	= generic_removexattr,
491#endif
492};
493
494const struct inode_operations f2fs_special_inode_operations = {
495	.setattr        = f2fs_setattr,
496	.get_acl	= f2fs_get_acl,
497#ifdef CONFIG_F2FS_FS_XATTR
498	.setxattr       = generic_setxattr,
499	.getxattr       = generic_getxattr,
500	.listxattr	= f2fs_listxattr,
501	.removexattr    = generic_removexattr,
502#endif
503};
504