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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2014 Filipe David Borba Manana <fdmanana@gmail.com>
4 */
5
6#include <linux/hashtable.h>
7#include "messages.h"
8#include "props.h"
9#include "btrfs_inode.h"
10#include "transaction.h"
11#include "ctree.h"
12#include "xattr.h"
13#include "compression.h"
14#include "space-info.h"
15#include "fs.h"
16#include "accessors.h"
17#include "super.h"
18#include "dir-item.h"
19
20#define BTRFS_PROP_HANDLERS_HT_BITS 8
21static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
22
23struct prop_handler {
24 struct hlist_node node;
25 const char *xattr_name;
26 int (*validate)(const struct btrfs_inode *inode, const char *value,
27 size_t len);
28 int (*apply)(struct inode *inode, const char *value, size_t len);
29 const char *(*extract)(struct inode *inode);
30 bool (*ignore)(const struct btrfs_inode *inode);
31 int inheritable;
32};
33
34static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
35{
36 struct hlist_head *h;
37
38 h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
39 if (hlist_empty(h))
40 return NULL;
41
42 return h;
43}
44
45static const struct prop_handler *
46find_prop_handler(const char *name,
47 const struct hlist_head *handlers)
48{
49 struct prop_handler *h;
50
51 if (!handlers) {
52 u64 hash = btrfs_name_hash(name, strlen(name));
53
54 handlers = find_prop_handlers_by_hash(hash);
55 if (!handlers)
56 return NULL;
57 }
58
59 hlist_for_each_entry(h, handlers, node)
60 if (!strcmp(h->xattr_name, name))
61 return h;
62
63 return NULL;
64}
65
66int btrfs_validate_prop(const struct btrfs_inode *inode, const char *name,
67 const char *value, size_t value_len)
68{
69 const struct prop_handler *handler;
70
71 if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
72 return -EINVAL;
73
74 handler = find_prop_handler(name, NULL);
75 if (!handler)
76 return -EINVAL;
77
78 if (value_len == 0)
79 return 0;
80
81 return handler->validate(inode, value, value_len);
82}
83
84/*
85 * Check if a property should be ignored (not set) for an inode.
86 *
87 * @inode: The target inode.
88 * @name: The property's name.
89 *
90 * The caller must be sure the given property name is valid, for example by
91 * having previously called btrfs_validate_prop().
92 *
93 * Returns: true if the property should be ignored for the given inode
94 * false if the property must not be ignored for the given inode
95 */
96bool btrfs_ignore_prop(const struct btrfs_inode *inode, const char *name)
97{
98 const struct prop_handler *handler;
99
100 handler = find_prop_handler(name, NULL);
101 ASSERT(handler != NULL);
102
103 return handler->ignore(inode);
104}
105
106int btrfs_set_prop(struct btrfs_trans_handle *trans, struct inode *inode,
107 const char *name, const char *value, size_t value_len,
108 int flags)
109{
110 const struct prop_handler *handler;
111 int ret;
112
113 handler = find_prop_handler(name, NULL);
114 if (!handler)
115 return -EINVAL;
116
117 if (value_len == 0) {
118 ret = btrfs_setxattr(trans, inode, handler->xattr_name,
119 NULL, 0, flags);
120 if (ret)
121 return ret;
122
123 ret = handler->apply(inode, NULL, 0);
124 ASSERT(ret == 0);
125
126 return ret;
127 }
128
129 ret = btrfs_setxattr(trans, inode, handler->xattr_name, value,
130 value_len, flags);
131 if (ret)
132 return ret;
133 ret = handler->apply(inode, value, value_len);
134 if (ret) {
135 btrfs_setxattr(trans, inode, handler->xattr_name, NULL,
136 0, flags);
137 return ret;
138 }
139
140 set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
141
142 return 0;
143}
144
145static int iterate_object_props(struct btrfs_root *root,
146 struct btrfs_path *path,
147 u64 objectid,
148 void (*iterator)(void *,
149 const struct prop_handler *,
150 const char *,
151 size_t),
152 void *ctx)
153{
154 int ret;
155 char *name_buf = NULL;
156 char *value_buf = NULL;
157 int name_buf_len = 0;
158 int value_buf_len = 0;
159
160 while (1) {
161 struct btrfs_key key;
162 struct btrfs_dir_item *di;
163 struct extent_buffer *leaf;
164 u32 total_len, cur, this_len;
165 int slot;
166 const struct hlist_head *handlers;
167
168 slot = path->slots[0];
169 leaf = path->nodes[0];
170
171 if (slot >= btrfs_header_nritems(leaf)) {
172 ret = btrfs_next_leaf(root, path);
173 if (ret < 0)
174 goto out;
175 else if (ret > 0)
176 break;
177 continue;
178 }
179
180 btrfs_item_key_to_cpu(leaf, &key, slot);
181 if (key.objectid != objectid)
182 break;
183 if (key.type != BTRFS_XATTR_ITEM_KEY)
184 break;
185
186 handlers = find_prop_handlers_by_hash(key.offset);
187 if (!handlers)
188 goto next_slot;
189
190 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
191 cur = 0;
192 total_len = btrfs_item_size(leaf, slot);
193
194 while (cur < total_len) {
195 u32 name_len = btrfs_dir_name_len(leaf, di);
196 u32 data_len = btrfs_dir_data_len(leaf, di);
197 unsigned long name_ptr, data_ptr;
198 const struct prop_handler *handler;
199
200 this_len = sizeof(*di) + name_len + data_len;
201 name_ptr = (unsigned long)(di + 1);
202 data_ptr = name_ptr + name_len;
203
204 if (name_len <= XATTR_BTRFS_PREFIX_LEN ||
205 memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
206 name_ptr,
207 XATTR_BTRFS_PREFIX_LEN))
208 goto next_dir_item;
209
210 if (name_len >= name_buf_len) {
211 kfree(name_buf);
212 name_buf_len = name_len + 1;
213 name_buf = kmalloc(name_buf_len, GFP_NOFS);
214 if (!name_buf) {
215 ret = -ENOMEM;
216 goto out;
217 }
218 }
219 read_extent_buffer(leaf, name_buf, name_ptr, name_len);
220 name_buf[name_len] = '\0';
221
222 handler = find_prop_handler(name_buf, handlers);
223 if (!handler)
224 goto next_dir_item;
225
226 if (data_len > value_buf_len) {
227 kfree(value_buf);
228 value_buf_len = data_len;
229 value_buf = kmalloc(data_len, GFP_NOFS);
230 if (!value_buf) {
231 ret = -ENOMEM;
232 goto out;
233 }
234 }
235 read_extent_buffer(leaf, value_buf, data_ptr, data_len);
236
237 iterator(ctx, handler, value_buf, data_len);
238next_dir_item:
239 cur += this_len;
240 di = (struct btrfs_dir_item *)((char *) di + this_len);
241 }
242
243next_slot:
244 path->slots[0]++;
245 }
246
247 ret = 0;
248out:
249 btrfs_release_path(path);
250 kfree(name_buf);
251 kfree(value_buf);
252
253 return ret;
254}
255
256static void inode_prop_iterator(void *ctx,
257 const struct prop_handler *handler,
258 const char *value,
259 size_t len)
260{
261 struct inode *inode = ctx;
262 struct btrfs_root *root = BTRFS_I(inode)->root;
263 int ret;
264
265 ret = handler->apply(inode, value, len);
266 if (unlikely(ret))
267 btrfs_warn(root->fs_info,
268 "error applying prop %s to ino %llu (root %llu): %d",
269 handler->xattr_name, btrfs_ino(BTRFS_I(inode)),
270 root->root_key.objectid, ret);
271 else
272 set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
273}
274
275int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path)
276{
277 struct btrfs_root *root = BTRFS_I(inode)->root;
278 u64 ino = btrfs_ino(BTRFS_I(inode));
279
280 return iterate_object_props(root, path, ino, inode_prop_iterator, inode);
281}
282
283static int prop_compression_validate(const struct btrfs_inode *inode,
284 const char *value, size_t len)
285{
286 if (!btrfs_inode_can_compress(inode))
287 return -EINVAL;
288
289 if (!value)
290 return 0;
291
292 if (btrfs_compress_is_valid_type(value, len))
293 return 0;
294
295 if ((len == 2 && strncmp("no", value, 2) == 0) ||
296 (len == 4 && strncmp("none", value, 4) == 0))
297 return 0;
298
299 return -EINVAL;
300}
301
302static int prop_compression_apply(struct inode *inode, const char *value,
303 size_t len)
304{
305 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
306 int type;
307
308 /* Reset to defaults */
309 if (len == 0) {
310 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
311 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
312 BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
313 return 0;
314 }
315
316 /* Set NOCOMPRESS flag */
317 if ((len == 2 && strncmp("no", value, 2) == 0) ||
318 (len == 4 && strncmp("none", value, 4) == 0)) {
319 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
320 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
321 BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
322
323 return 0;
324 }
325
326 if (!strncmp("lzo", value, 3)) {
327 type = BTRFS_COMPRESS_LZO;
328 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
329 } else if (!strncmp("zlib", value, 4)) {
330 type = BTRFS_COMPRESS_ZLIB;
331 } else if (!strncmp("zstd", value, 4)) {
332 type = BTRFS_COMPRESS_ZSTD;
333 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
334 } else {
335 return -EINVAL;
336 }
337
338 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
339 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
340 BTRFS_I(inode)->prop_compress = type;
341
342 return 0;
343}
344
345static bool prop_compression_ignore(const struct btrfs_inode *inode)
346{
347 /*
348 * Compression only has effect for regular files, and for directories
349 * we set it just to propagate it to new files created inside them.
350 * Everything else (symlinks, devices, sockets, fifos) is pointless as
351 * it will do nothing, so don't waste metadata space on a compression
352 * xattr for anything that is neither a file nor a directory.
353 */
354 if (!S_ISREG(inode->vfs_inode.i_mode) &&
355 !S_ISDIR(inode->vfs_inode.i_mode))
356 return true;
357
358 return false;
359}
360
361static const char *prop_compression_extract(struct inode *inode)
362{
363 switch (BTRFS_I(inode)->prop_compress) {
364 case BTRFS_COMPRESS_ZLIB:
365 case BTRFS_COMPRESS_LZO:
366 case BTRFS_COMPRESS_ZSTD:
367 return btrfs_compress_type2str(BTRFS_I(inode)->prop_compress);
368 default:
369 break;
370 }
371
372 return NULL;
373}
374
375static struct prop_handler prop_handlers[] = {
376 {
377 .xattr_name = XATTR_BTRFS_PREFIX "compression",
378 .validate = prop_compression_validate,
379 .apply = prop_compression_apply,
380 .extract = prop_compression_extract,
381 .ignore = prop_compression_ignore,
382 .inheritable = 1
383 },
384};
385
386int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
387 struct inode *inode, struct inode *parent)
388{
389 struct btrfs_root *root = BTRFS_I(inode)->root;
390 struct btrfs_fs_info *fs_info = root->fs_info;
391 int ret;
392 int i;
393 bool need_reserve = false;
394
395 if (!test_bit(BTRFS_INODE_HAS_PROPS,
396 &BTRFS_I(parent)->runtime_flags))
397 return 0;
398
399 for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
400 const struct prop_handler *h = &prop_handlers[i];
401 const char *value;
402 u64 num_bytes = 0;
403
404 if (!h->inheritable)
405 continue;
406
407 if (h->ignore(BTRFS_I(inode)))
408 continue;
409
410 value = h->extract(parent);
411 if (!value)
412 continue;
413
414 /*
415 * This is not strictly necessary as the property should be
416 * valid, but in case it isn't, don't propagate it further.
417 */
418 ret = h->validate(BTRFS_I(inode), value, strlen(value));
419 if (ret)
420 continue;
421
422 /*
423 * Currently callers should be reserving 1 item for properties,
424 * since we only have 1 property that we currently support. If
425 * we add more in the future we need to try and reserve more
426 * space for them. But we should also revisit how we do space
427 * reservations if we do add more properties in the future.
428 */
429 if (need_reserve) {
430 num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
431 ret = btrfs_block_rsv_add(fs_info, trans->block_rsv,
432 num_bytes,
433 BTRFS_RESERVE_NO_FLUSH);
434 if (ret)
435 return ret;
436 }
437
438 ret = btrfs_setxattr(trans, inode, h->xattr_name, value,
439 strlen(value), 0);
440 if (!ret) {
441 ret = h->apply(inode, value, strlen(value));
442 if (ret)
443 btrfs_setxattr(trans, inode, h->xattr_name,
444 NULL, 0, 0);
445 else
446 set_bit(BTRFS_INODE_HAS_PROPS,
447 &BTRFS_I(inode)->runtime_flags);
448 }
449
450 if (need_reserve) {
451 btrfs_block_rsv_release(fs_info, trans->block_rsv,
452 num_bytes, NULL);
453 if (ret)
454 return ret;
455 }
456 need_reserve = true;
457 }
458
459 return 0;
460}
461
462int __init btrfs_props_init(void)
463{
464 int i;
465
466 for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
467 struct prop_handler *p = &prop_handlers[i];
468 u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));
469
470 hash_add(prop_handlers_ht, &p->node, h);
471 }
472 return 0;
473}
474
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2014 Filipe David Borba Manana <fdmanana@gmail.com>
4 */
5
6#include <linux/hashtable.h>
7#include "props.h"
8#include "btrfs_inode.h"
9#include "transaction.h"
10#include "ctree.h"
11#include "xattr.h"
12#include "compression.h"
13
14#define BTRFS_PROP_HANDLERS_HT_BITS 8
15static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
16
17struct prop_handler {
18 struct hlist_node node;
19 const char *xattr_name;
20 int (*validate)(const char *value, size_t len);
21 int (*apply)(struct inode *inode, const char *value, size_t len);
22 const char *(*extract)(struct inode *inode);
23 int inheritable;
24};
25
26static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
27{
28 struct hlist_head *h;
29
30 h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
31 if (hlist_empty(h))
32 return NULL;
33
34 return h;
35}
36
37static const struct prop_handler *
38find_prop_handler(const char *name,
39 const struct hlist_head *handlers)
40{
41 struct prop_handler *h;
42
43 if (!handlers) {
44 u64 hash = btrfs_name_hash(name, strlen(name));
45
46 handlers = find_prop_handlers_by_hash(hash);
47 if (!handlers)
48 return NULL;
49 }
50
51 hlist_for_each_entry(h, handlers, node)
52 if (!strcmp(h->xattr_name, name))
53 return h;
54
55 return NULL;
56}
57
58int btrfs_validate_prop(const char *name, const char *value, size_t value_len)
59{
60 const struct prop_handler *handler;
61
62 if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
63 return -EINVAL;
64
65 handler = find_prop_handler(name, NULL);
66 if (!handler)
67 return -EINVAL;
68
69 if (value_len == 0)
70 return 0;
71
72 return handler->validate(value, value_len);
73}
74
75int btrfs_set_prop(struct btrfs_trans_handle *trans, struct inode *inode,
76 const char *name, const char *value, size_t value_len,
77 int flags)
78{
79 const struct prop_handler *handler;
80 int ret;
81
82 handler = find_prop_handler(name, NULL);
83 if (!handler)
84 return -EINVAL;
85
86 if (value_len == 0) {
87 ret = btrfs_setxattr(trans, inode, handler->xattr_name,
88 NULL, 0, flags);
89 if (ret)
90 return ret;
91
92 ret = handler->apply(inode, NULL, 0);
93 ASSERT(ret == 0);
94
95 return ret;
96 }
97
98 ret = btrfs_setxattr(trans, inode, handler->xattr_name, value,
99 value_len, flags);
100 if (ret)
101 return ret;
102 ret = handler->apply(inode, value, value_len);
103 if (ret) {
104 btrfs_setxattr(trans, inode, handler->xattr_name, NULL,
105 0, flags);
106 return ret;
107 }
108
109 set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
110
111 return 0;
112}
113
114static int iterate_object_props(struct btrfs_root *root,
115 struct btrfs_path *path,
116 u64 objectid,
117 void (*iterator)(void *,
118 const struct prop_handler *,
119 const char *,
120 size_t),
121 void *ctx)
122{
123 int ret;
124 char *name_buf = NULL;
125 char *value_buf = NULL;
126 int name_buf_len = 0;
127 int value_buf_len = 0;
128
129 while (1) {
130 struct btrfs_key key;
131 struct btrfs_dir_item *di;
132 struct extent_buffer *leaf;
133 u32 total_len, cur, this_len;
134 int slot;
135 const struct hlist_head *handlers;
136
137 slot = path->slots[0];
138 leaf = path->nodes[0];
139
140 if (slot >= btrfs_header_nritems(leaf)) {
141 ret = btrfs_next_leaf(root, path);
142 if (ret < 0)
143 goto out;
144 else if (ret > 0)
145 break;
146 continue;
147 }
148
149 btrfs_item_key_to_cpu(leaf, &key, slot);
150 if (key.objectid != objectid)
151 break;
152 if (key.type != BTRFS_XATTR_ITEM_KEY)
153 break;
154
155 handlers = find_prop_handlers_by_hash(key.offset);
156 if (!handlers)
157 goto next_slot;
158
159 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
160 cur = 0;
161 total_len = btrfs_item_size_nr(leaf, slot);
162
163 while (cur < total_len) {
164 u32 name_len = btrfs_dir_name_len(leaf, di);
165 u32 data_len = btrfs_dir_data_len(leaf, di);
166 unsigned long name_ptr, data_ptr;
167 const struct prop_handler *handler;
168
169 this_len = sizeof(*di) + name_len + data_len;
170 name_ptr = (unsigned long)(di + 1);
171 data_ptr = name_ptr + name_len;
172
173 if (name_len <= XATTR_BTRFS_PREFIX_LEN ||
174 memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
175 name_ptr,
176 XATTR_BTRFS_PREFIX_LEN))
177 goto next_dir_item;
178
179 if (name_len >= name_buf_len) {
180 kfree(name_buf);
181 name_buf_len = name_len + 1;
182 name_buf = kmalloc(name_buf_len, GFP_NOFS);
183 if (!name_buf) {
184 ret = -ENOMEM;
185 goto out;
186 }
187 }
188 read_extent_buffer(leaf, name_buf, name_ptr, name_len);
189 name_buf[name_len] = '\0';
190
191 handler = find_prop_handler(name_buf, handlers);
192 if (!handler)
193 goto next_dir_item;
194
195 if (data_len > value_buf_len) {
196 kfree(value_buf);
197 value_buf_len = data_len;
198 value_buf = kmalloc(data_len, GFP_NOFS);
199 if (!value_buf) {
200 ret = -ENOMEM;
201 goto out;
202 }
203 }
204 read_extent_buffer(leaf, value_buf, data_ptr, data_len);
205
206 iterator(ctx, handler, value_buf, data_len);
207next_dir_item:
208 cur += this_len;
209 di = (struct btrfs_dir_item *)((char *) di + this_len);
210 }
211
212next_slot:
213 path->slots[0]++;
214 }
215
216 ret = 0;
217out:
218 btrfs_release_path(path);
219 kfree(name_buf);
220 kfree(value_buf);
221
222 return ret;
223}
224
225static void inode_prop_iterator(void *ctx,
226 const struct prop_handler *handler,
227 const char *value,
228 size_t len)
229{
230 struct inode *inode = ctx;
231 struct btrfs_root *root = BTRFS_I(inode)->root;
232 int ret;
233
234 ret = handler->apply(inode, value, len);
235 if (unlikely(ret))
236 btrfs_warn(root->fs_info,
237 "error applying prop %s to ino %llu (root %llu): %d",
238 handler->xattr_name, btrfs_ino(BTRFS_I(inode)),
239 root->root_key.objectid, ret);
240 else
241 set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
242}
243
244int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path)
245{
246 struct btrfs_root *root = BTRFS_I(inode)->root;
247 u64 ino = btrfs_ino(BTRFS_I(inode));
248 int ret;
249
250 ret = iterate_object_props(root, path, ino, inode_prop_iterator, inode);
251
252 return ret;
253}
254
255static int prop_compression_validate(const char *value, size_t len)
256{
257 if (!value)
258 return 0;
259
260 if (btrfs_compress_is_valid_type(value, len))
261 return 0;
262
263 if ((len == 2 && strncmp("no", value, 2) == 0) ||
264 (len == 4 && strncmp("none", value, 4) == 0))
265 return 0;
266
267 return -EINVAL;
268}
269
270static int prop_compression_apply(struct inode *inode, const char *value,
271 size_t len)
272{
273 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
274 int type;
275
276 /* Reset to defaults */
277 if (len == 0) {
278 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
279 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
280 BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
281 return 0;
282 }
283
284 /* Set NOCOMPRESS flag */
285 if ((len == 2 && strncmp("no", value, 2) == 0) ||
286 (len == 4 && strncmp("none", value, 4) == 0)) {
287 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
288 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
289 BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
290
291 return 0;
292 }
293
294 if (!strncmp("lzo", value, 3)) {
295 type = BTRFS_COMPRESS_LZO;
296 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
297 } else if (!strncmp("zlib", value, 4)) {
298 type = BTRFS_COMPRESS_ZLIB;
299 } else if (!strncmp("zstd", value, 4)) {
300 type = BTRFS_COMPRESS_ZSTD;
301 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
302 } else {
303 return -EINVAL;
304 }
305
306 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
307 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
308 BTRFS_I(inode)->prop_compress = type;
309
310 return 0;
311}
312
313static const char *prop_compression_extract(struct inode *inode)
314{
315 switch (BTRFS_I(inode)->prop_compress) {
316 case BTRFS_COMPRESS_ZLIB:
317 case BTRFS_COMPRESS_LZO:
318 case BTRFS_COMPRESS_ZSTD:
319 return btrfs_compress_type2str(BTRFS_I(inode)->prop_compress);
320 default:
321 break;
322 }
323
324 return NULL;
325}
326
327static struct prop_handler prop_handlers[] = {
328 {
329 .xattr_name = XATTR_BTRFS_PREFIX "compression",
330 .validate = prop_compression_validate,
331 .apply = prop_compression_apply,
332 .extract = prop_compression_extract,
333 .inheritable = 1
334 },
335};
336
337static int inherit_props(struct btrfs_trans_handle *trans,
338 struct inode *inode,
339 struct inode *parent)
340{
341 struct btrfs_root *root = BTRFS_I(inode)->root;
342 struct btrfs_fs_info *fs_info = root->fs_info;
343 int ret;
344 int i;
345 bool need_reserve = false;
346
347 if (!test_bit(BTRFS_INODE_HAS_PROPS,
348 &BTRFS_I(parent)->runtime_flags))
349 return 0;
350
351 for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
352 const struct prop_handler *h = &prop_handlers[i];
353 const char *value;
354 u64 num_bytes = 0;
355
356 if (!h->inheritable)
357 continue;
358
359 value = h->extract(parent);
360 if (!value)
361 continue;
362
363 /*
364 * This is not strictly necessary as the property should be
365 * valid, but in case it isn't, don't propagate it further.
366 */
367 ret = h->validate(value, strlen(value));
368 if (ret)
369 continue;
370
371 /*
372 * Currently callers should be reserving 1 item for properties,
373 * since we only have 1 property that we currently support. If
374 * we add more in the future we need to try and reserve more
375 * space for them. But we should also revisit how we do space
376 * reservations if we do add more properties in the future.
377 */
378 if (need_reserve) {
379 num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
380 ret = btrfs_block_rsv_add(root, trans->block_rsv,
381 num_bytes, BTRFS_RESERVE_NO_FLUSH);
382 if (ret)
383 return ret;
384 }
385
386 ret = btrfs_setxattr(trans, inode, h->xattr_name, value,
387 strlen(value), 0);
388 if (!ret) {
389 ret = h->apply(inode, value, strlen(value));
390 if (ret)
391 btrfs_setxattr(trans, inode, h->xattr_name,
392 NULL, 0, 0);
393 else
394 set_bit(BTRFS_INODE_HAS_PROPS,
395 &BTRFS_I(inode)->runtime_flags);
396 }
397
398 if (need_reserve) {
399 btrfs_block_rsv_release(fs_info, trans->block_rsv,
400 num_bytes, NULL);
401 if (ret)
402 return ret;
403 }
404 need_reserve = true;
405 }
406
407 return 0;
408}
409
410int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
411 struct inode *inode,
412 struct inode *dir)
413{
414 if (!dir)
415 return 0;
416
417 return inherit_props(trans, inode, dir);
418}
419
420int btrfs_subvol_inherit_props(struct btrfs_trans_handle *trans,
421 struct btrfs_root *root,
422 struct btrfs_root *parent_root)
423{
424 struct super_block *sb = root->fs_info->sb;
425 struct inode *parent_inode, *child_inode;
426 int ret;
427
428 parent_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, parent_root);
429 if (IS_ERR(parent_inode))
430 return PTR_ERR(parent_inode);
431
432 child_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, root);
433 if (IS_ERR(child_inode)) {
434 iput(parent_inode);
435 return PTR_ERR(child_inode);
436 }
437
438 ret = inherit_props(trans, child_inode, parent_inode);
439 iput(child_inode);
440 iput(parent_inode);
441
442 return ret;
443}
444
445void __init btrfs_props_init(void)
446{
447 int i;
448
449 for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
450 struct prop_handler *p = &prop_handlers[i];
451 u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));
452
453 hash_add(prop_handlers_ht, &p->node, h);
454 }
455}
456