summaryrefslogtreecommitdiffstats
path: root/fs/erofs/inode.c
blob: 36e638e8b53a3d290fcb7ade23a40dc4805be9e6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2017-2018 HUAWEI, Inc.
 *             https://www.huawei.com/
 * Copyright (C) 2021, Alibaba Cloud
 */
#include "xattr.h"

#include <trace/events/erofs.h>

static void *erofs_read_inode(struct erofs_buf *buf,
			      struct inode *inode, unsigned int *ofs)
{
	struct super_block *sb = inode->i_sb;
	struct erofs_sb_info *sbi = EROFS_SB(sb);
	struct erofs_inode *vi = EROFS_I(inode);
	const erofs_off_t inode_loc = erofs_iloc(inode);
	erofs_blk_t blkaddr, nblks = 0;
	void *kaddr;
	struct erofs_inode_compact *dic;
	struct erofs_inode_extended *die, *copied = NULL;
	union erofs_inode_i_u iu;
	unsigned int ifmt;
	int err;

	blkaddr = erofs_blknr(sb, inode_loc);
	*ofs = erofs_blkoff(sb, inode_loc);

	kaddr = erofs_read_metabuf(buf, sb, blkaddr, EROFS_KMAP);
	if (IS_ERR(kaddr)) {
		erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",
			  vi->nid, PTR_ERR(kaddr));
		return kaddr;
	}

	dic = kaddr + *ofs;
	ifmt = le16_to_cpu(dic->i_format);
	if (ifmt & ~EROFS_I_ALL) {
		erofs_err(sb, "unsupported i_format %u of nid %llu",
			  ifmt, vi->nid);
		err = -EOPNOTSUPP;
		goto err_out;
	}

	vi->datalayout = erofs_inode_datalayout(ifmt);
	if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) {
		erofs_err(sb, "unsupported datalayout %u of nid %llu",
			  vi->datalayout, vi->nid);
		err = -EOPNOTSUPP;
		goto err_out;
	}

	switch (erofs_inode_version(ifmt)) {
	case EROFS_INODE_LAYOUT_EXTENDED:
		vi->inode_isize = sizeof(struct erofs_inode_extended);
		/* check if the extended inode acrosses block boundary */
		if (*ofs + vi->inode_isize <= sb->s_blocksize) {
			*ofs += vi->inode_isize;
			die = (struct erofs_inode_extended *)dic;
		} else {
			const unsigned int gotten = sb->s_blocksize - *ofs;

			copied = kmalloc(vi->inode_isize, GFP_KERNEL);
			if (!copied) {
				err = -ENOMEM;
				goto err_out;
			}
			memcpy(copied, dic, gotten);
			kaddr = erofs_read_metabuf(buf, sb, blkaddr + 1,
						   EROFS_KMAP);
			if (IS_ERR(kaddr)) {
				erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld",
					  vi->nid, PTR_ERR(kaddr));
				kfree(copied);
				return kaddr;
			}
			*ofs = vi->inode_isize - gotten;
			memcpy((u8 *)copied + gotten, kaddr, *ofs);
			die = copied;
		}
		vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);

		inode->i_mode = le16_to_cpu(die->i_mode);
		iu = die->i_u;
		i_uid_write(inode, le32_to_cpu(die->i_uid));
		i_gid_write(inode, le32_to_cpu(die->i_gid));
		set_nlink(inode, le32_to_cpu(die->i_nlink));
		/* each extended inode has its own timestamp */
		inode_set_ctime(inode, le64_to_cpu(die->i_mtime),
				le32_to_cpu(die->i_mtime_nsec));

		inode->i_size = le64_to_cpu(die->i_size);
		kfree(copied);
		copied = NULL;
		break;
	case EROFS_INODE_LAYOUT_COMPACT:
		vi->inode_isize = sizeof(struct erofs_inode_compact);
		*ofs += vi->inode_isize;
		vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount);

		inode->i_mode = le16_to_cpu(dic->i_mode);
		iu = dic->i_u;
		i_uid_write(inode, le16_to_cpu(dic->i_uid));
		i_gid_write(inode, le16_to_cpu(dic->i_gid));
		set_nlink(inode, le16_to_cpu(dic->i_nlink));
		/* use build time for compact inodes */
		inode_set_ctime(inode, sbi->build_time, sbi->build_time_nsec);

		inode->i_size = le32_to_cpu(dic->i_size);
		break;
	default:
		erofs_err(sb, "unsupported on-disk inode version %u of nid %llu",
			  erofs_inode_version(ifmt), vi->nid);
		err = -EOPNOTSUPP;
		goto err_out;
	}

	switch (inode->i_mode & S_IFMT) {
	case S_IFREG:
	case S_IFDIR:
	case S_IFLNK:
		vi->raw_blkaddr = le32_to_cpu(iu.raw_blkaddr);
		break;
	case S_IFCHR:
	case S_IFBLK:
		inode->i_rdev = new_decode_dev(le32_to_cpu(iu.rdev));
		break;
	case S_IFIFO:
	case S_IFSOCK:
		inode->i_rdev = 0;
		break;
	default:
		erofs_err(sb, "bogus i_mode (%o) @ nid %llu", inode->i_mode,
			  vi->nid);
		err = -EFSCORRUPTED;
		goto err_out;
	}

	/* total blocks for compressed files */
	if (erofs_inode_is_data_compressed(vi->datalayout)) {
		nblks = le32_to_cpu(iu.compressed_blocks);
	} else if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
		/* fill chunked inode summary info */
		vi->chunkformat = le16_to_cpu(iu.c.format);
		if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
			erofs_err(sb, "unsupported chunk format %x of nid %llu",
				  vi->chunkformat, vi->nid);
			err = -EOPNOTSUPP;
			goto err_out;
		}
		vi->chunkbits = sb->s_blocksize_bits +
			(vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
	}
	inode_set_mtime_to_ts(inode,
			      inode_set_atime_to_ts(inode, inode_get_ctime(inode)));

	inode->i_flags &= ~S_DAX;
	if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
	    (vi->datalayout == EROFS_INODE_FLAT_PLAIN ||
	     vi->datalayout == EROFS_INODE_CHUNK_BASED))
		inode->i_flags |= S_DAX;

	if (!nblks)
		/* measure inode.i_blocks as generic filesystems */
		inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;
	else
		inode->i_blocks = nblks << (sb->s_blocksize_bits - 9);
	return kaddr;

err_out:
	DBG_BUGON(1);
	kfree(copied);
	erofs_put_metabuf(buf);
	return ERR_PTR(err);
}

static int erofs_fill_symlink(struct inode *inode, void *kaddr,
			      unsigned int m_pofs)
{
	struct erofs_inode *vi = EROFS_I(inode);
	unsigned int bsz = i_blocksize(inode);
	char *lnk;

	/* if it cannot be handled with fast symlink scheme */
	if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
	    inode->i_size >= bsz || inode->i_size < 0) {
		inode->i_op = &erofs_symlink_iops;
		return 0;
	}

	lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);
	if (!lnk)
		return -ENOMEM;

	m_pofs += vi->xattr_isize;
	/* inline symlink data shouldn't cross block boundary */
	if (m_pofs + inode->i_size > bsz) {
		kfree(lnk);
		erofs_err(inode->i_sb,
			  "inline data cross block boundary @ nid %llu",
			  vi->nid);
		DBG_BUGON(1);
		return -EFSCORRUPTED;
	}
	memcpy(lnk, kaddr + m_pofs, inode->i_size);
	lnk[inode->i_size] = '\0';

	inode->i_link = lnk;
	inode->i_op = &erofs_fast_symlink_iops;
	return 0;
}

static int erofs_fill_inode(struct inode *inode)
{
	struct erofs_inode *vi = EROFS_I(inode);
	struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
	void *kaddr;
	unsigned int ofs;
	int err = 0;

	trace_erofs_fill_inode(inode);

	/* read inode base data from disk */
	kaddr = erofs_read_inode(&buf, inode, &ofs);
	if (IS_ERR(kaddr))
		return PTR_ERR(kaddr);

	/* setup the new inode */
	switch (inode->i_mode & S_IFMT) {
	case S_IFREG:
		inode->i_op = &erofs_generic_iops;
		if (erofs_inode_is_data_compressed(vi->datalayout))
			inode->i_fop = &generic_ro_fops;
		else
			inode->i_fop = &erofs_file_fops;
		break;
	case S_IFDIR:
		inode->i_op = &erofs_dir_iops;
		inode->i_fop = &erofs_dir_fops;
		inode_nohighmem(inode);
		break;
	case S_IFLNK:
		err = erofs_fill_symlink(inode, kaddr, ofs);
		if (err)
			goto out_unlock;
		inode_nohighmem(inode);
		break;
	case S_IFCHR:
	case S_IFBLK:
	case S_IFIFO:
	case S_IFSOCK:
		inode->i_op = &erofs_generic_iops;
		init_special_inode(inode, inode->i_mode, inode->i_rdev);
		goto out_unlock;
	default:
		err = -EFSCORRUPTED;
		goto out_unlock;
	}

	if (erofs_inode_is_data_compressed(vi->datalayout)) {
#ifdef CONFIG_EROFS_FS_ZIP
		if (!erofs_is_fscache_mode(inode->i_sb)) {
			DO_ONCE_LITE_IF(inode->i_sb->s_blocksize != PAGE_SIZE,
				  erofs_info, inode->i_sb,
				  "EXPERIMENTAL EROFS subpage compressed block support in use. Use at your own risk!");
			inode->i_mapping->a_ops = &z_erofs_aops;
			err = 0;
			goto out_unlock;
		}
#endif
		err = -EOPNOTSUPP;
		goto out_unlock;
	}
	inode->i_mapping->a_ops = &erofs_raw_access_aops;
	mapping_set_large_folios(inode->i_mapping);
#ifdef CONFIG_EROFS_FS_ONDEMAND
	if (erofs_is_fscache_mode(inode->i_sb))
		inode->i_mapping->a_ops = &erofs_fscache_access_aops;
#endif

out_unlock:
	erofs_put_metabuf(&buf);
	return err;
}

/*
 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
 * so that it will fit.
 */
static ino_t erofs_squash_ino(erofs_nid_t nid)
{
	ino_t ino = (ino_t)nid;

	if (sizeof(ino_t) < sizeof(erofs_nid_t))
		ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
	return ino;
}

static int erofs_iget5_eq(struct inode *inode, void *opaque)
{
	return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;
}

static int erofs_iget5_set(struct inode *inode, void *opaque)
{
	const erofs_nid_t nid = *(erofs_nid_t *)opaque;

	inode->i_ino = erofs_squash_ino(nid);
	EROFS_I(inode)->nid = nid;
	return 0;
}

struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)
{
	struct inode *inode;

	inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq,
			     erofs_iget5_set, &nid);
	if (!inode)
		return ERR_PTR(-ENOMEM);

	if (inode->i_state & I_NEW) {
		int err = erofs_fill_inode(inode);

		if (err) {
			iget_failed(inode);
			return ERR_PTR(err);
		}
		unlock_new_inode(inode);
	}
	return inode;
}

int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
		  struct kstat *stat, u32 request_mask,
		  unsigned int query_flags)
{
	struct inode *const inode = d_inode(path->dentry);

	if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout))
		stat->attributes |= STATX_ATTR_COMPRESSED;

	stat->attributes |= STATX_ATTR_IMMUTABLE;
	stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
				  STATX_ATTR_IMMUTABLE);

	generic_fillattr(idmap, request_mask, inode, stat);
	return 0;
}

const struct inode_operations erofs_generic_iops = {
	.getattr = erofs_getattr,
	.listxattr = erofs_listxattr,
	.get_inode_acl = erofs_get_acl,
	.fiemap = erofs_fiemap,
};

const struct inode_operations erofs_symlink_iops = {
	.get_link = page_get_link,
	.getattr = erofs_getattr,
	.listxattr = erofs_listxattr,
	.get_inode_acl = erofs_get_acl,
};

const struct inode_operations erofs_fast_symlink_iops = {
	.get_link = simple_get_link,
	.getattr = erofs_getattr,
	.listxattr = erofs_listxattr,
	.get_inode_acl = erofs_get_acl,
};