1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2014 Filipe David Borba Manana <fdmanana@gmail.com>
6 #include <linux/hashtable.h>
8 #include "btrfs_inode.h"
9 #include "transaction.h"
12 #include "compression.h"
14 #define BTRFS_PROP_HANDLERS_HT_BITS 8
15 static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
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);
26 static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
30 h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
37 static const struct prop_handler *
38 find_prop_handler(const char *name,
39 const struct hlist_head *handlers)
41 struct prop_handler *h;
44 u64 hash = btrfs_name_hash(name, strlen(name));
46 handlers = find_prop_handlers_by_hash(hash);
51 hlist_for_each_entry(h, handlers, node)
52 if (!strcmp(h->xattr_name, name))
58 int btrfs_validate_prop(const char *name, const char *value, size_t value_len)
60 const struct prop_handler *handler;
62 if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
65 handler = find_prop_handler(name, NULL);
72 return handler->validate(value, value_len);
75 int btrfs_set_prop(struct btrfs_trans_handle *trans, struct inode *inode,
76 const char *name, const char *value, size_t value_len,
79 const struct prop_handler *handler;
82 handler = find_prop_handler(name, NULL);
87 ret = btrfs_setxattr(trans, inode, handler->xattr_name,
92 ret = handler->apply(inode, NULL, 0);
98 ret = btrfs_setxattr(trans, inode, handler->xattr_name, value,
102 ret = handler->apply(inode, value, value_len);
104 btrfs_setxattr(trans, inode, handler->xattr_name, NULL,
109 set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
114 static int iterate_object_props(struct btrfs_root *root,
115 struct btrfs_path *path,
117 void (*iterator)(void *,
118 const struct prop_handler *,
124 char *name_buf = NULL;
125 char *value_buf = NULL;
126 int name_buf_len = 0;
127 int value_buf_len = 0;
130 struct btrfs_key key;
131 struct btrfs_dir_item *di;
132 struct extent_buffer *leaf;
133 u32 total_len, cur, this_len;
135 const struct hlist_head *handlers;
137 slot = path->slots[0];
138 leaf = path->nodes[0];
140 if (slot >= btrfs_header_nritems(leaf)) {
141 ret = btrfs_next_leaf(root, path);
149 btrfs_item_key_to_cpu(leaf, &key, slot);
150 if (key.objectid != objectid)
152 if (key.type != BTRFS_XATTR_ITEM_KEY)
155 handlers = find_prop_handlers_by_hash(key.offset);
159 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
161 total_len = btrfs_item_size_nr(leaf, slot);
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;
169 this_len = sizeof(*di) + name_len + data_len;
170 name_ptr = (unsigned long)(di + 1);
171 data_ptr = name_ptr + name_len;
173 if (name_len <= XATTR_BTRFS_PREFIX_LEN ||
174 memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
176 XATTR_BTRFS_PREFIX_LEN))
179 if (name_len >= name_buf_len) {
181 name_buf_len = name_len + 1;
182 name_buf = kmalloc(name_buf_len, GFP_NOFS);
188 read_extent_buffer(leaf, name_buf, name_ptr, name_len);
189 name_buf[name_len] = '\0';
191 handler = find_prop_handler(name_buf, handlers);
195 if (data_len > value_buf_len) {
197 value_buf_len = data_len;
198 value_buf = kmalloc(data_len, GFP_NOFS);
204 read_extent_buffer(leaf, value_buf, data_ptr, data_len);
206 iterator(ctx, handler, value_buf, data_len);
209 di = (struct btrfs_dir_item *)((char *) di + this_len);
218 btrfs_release_path(path);
225 static void inode_prop_iterator(void *ctx,
226 const struct prop_handler *handler,
230 struct inode *inode = ctx;
231 struct btrfs_root *root = BTRFS_I(inode)->root;
234 ret = handler->apply(inode, value, len);
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);
241 set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
244 int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path)
246 struct btrfs_root *root = BTRFS_I(inode)->root;
247 u64 ino = btrfs_ino(BTRFS_I(inode));
250 ret = iterate_object_props(root, path, ino, inode_prop_iterator, inode);
255 static int prop_compression_validate(const char *value, size_t len)
260 if (btrfs_compress_is_valid_type(value, len))
266 static int prop_compression_apply(struct inode *inode, const char *value,
269 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
273 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
274 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
275 BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
280 if (!strncmp("lzo", value, 3)) {
281 type = BTRFS_COMPRESS_LZO;
282 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
283 } else if (!strncmp("zlib", value, 4)) {
284 type = BTRFS_COMPRESS_ZLIB;
285 } else if (!strncmp("zstd", value, 4)) {
286 type = BTRFS_COMPRESS_ZSTD;
287 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
292 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
293 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
294 BTRFS_I(inode)->prop_compress = type;
299 static const char *prop_compression_extract(struct inode *inode)
301 switch (BTRFS_I(inode)->prop_compress) {
302 case BTRFS_COMPRESS_ZLIB:
303 case BTRFS_COMPRESS_LZO:
304 case BTRFS_COMPRESS_ZSTD:
305 return btrfs_compress_type2str(BTRFS_I(inode)->prop_compress);
313 static struct prop_handler prop_handlers[] = {
315 .xattr_name = XATTR_BTRFS_PREFIX "compression",
316 .validate = prop_compression_validate,
317 .apply = prop_compression_apply,
318 .extract = prop_compression_extract,
323 static int inherit_props(struct btrfs_trans_handle *trans,
325 struct inode *parent)
327 struct btrfs_root *root = BTRFS_I(inode)->root;
328 struct btrfs_fs_info *fs_info = root->fs_info;
331 bool need_reserve = false;
333 if (!test_bit(BTRFS_INODE_HAS_PROPS,
334 &BTRFS_I(parent)->runtime_flags))
337 for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
338 const struct prop_handler *h = &prop_handlers[i];
345 value = h->extract(parent);
350 * This is not strictly necessary as the property should be
351 * valid, but in case it isn't, don't propagate it futher.
353 ret = h->validate(value, strlen(value));
358 * Currently callers should be reserving 1 item for properties,
359 * since we only have 1 property that we currently support. If
360 * we add more in the future we need to try and reserve more
361 * space for them. But we should also revisit how we do space
362 * reservations if we do add more properties in the future.
365 num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
366 ret = btrfs_block_rsv_add(root, trans->block_rsv,
367 num_bytes, BTRFS_RESERVE_NO_FLUSH);
372 ret = btrfs_setxattr(trans, inode, h->xattr_name, value,
375 ret = h->apply(inode, value, strlen(value));
377 btrfs_setxattr(trans, inode, h->xattr_name,
380 set_bit(BTRFS_INODE_HAS_PROPS,
381 &BTRFS_I(inode)->runtime_flags);
385 btrfs_block_rsv_release(fs_info, trans->block_rsv,
396 int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
403 return inherit_props(trans, inode, dir);
406 int btrfs_subvol_inherit_props(struct btrfs_trans_handle *trans,
407 struct btrfs_root *root,
408 struct btrfs_root *parent_root)
410 struct super_block *sb = root->fs_info->sb;
411 struct inode *parent_inode, *child_inode;
414 parent_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, parent_root);
415 if (IS_ERR(parent_inode))
416 return PTR_ERR(parent_inode);
418 child_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, root);
419 if (IS_ERR(child_inode)) {
421 return PTR_ERR(child_inode);
424 ret = inherit_props(trans, child_inode, parent_inode);
431 void __init btrfs_props_init(void)
435 for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
436 struct prop_handler *p = &prop_handlers[i];
437 u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));
439 hash_add(prop_handlers_ht, &p->node, h);