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v6.13.7
  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 <linux/xattr.h>
  8#include "messages.h"
  9#include "props.h"
 10#include "btrfs_inode.h"
 
 11#include "transaction.h"
 12#include "ctree.h"
 13#include "xattr.h"
 14#include "compression.h"
 15#include "space-info.h"
 16#include "fs.h"
 17#include "accessors.h"
 18#include "super.h"
 19#include "dir-item.h"
 20
 21#define BTRFS_PROP_HANDLERS_HT_BITS 8
 22static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
 23
 24struct prop_handler {
 25	struct hlist_node node;
 26	const char *xattr_name;
 27	int (*validate)(const struct btrfs_inode *inode, const char *value,
 28			size_t len);
 29	int (*apply)(struct inode *inode, const char *value, size_t len);
 30	const char *(*extract)(const struct inode *inode);
 31	bool (*ignore)(const struct btrfs_inode *inode);
 32	int inheritable;
 33};
 34
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 35static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
 36{
 37	struct hlist_head *h;
 38
 39	h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
 40	if (hlist_empty(h))
 41		return NULL;
 42
 43	return h;
 44}
 45
 46static const struct prop_handler *
 47find_prop_handler(const char *name,
 48		  const struct hlist_head *handlers)
 49{
 50	struct prop_handler *h;
 51
 52	if (!handlers) {
 53		u64 hash = btrfs_name_hash(name, strlen(name));
 54
 55		handlers = find_prop_handlers_by_hash(hash);
 56		if (!handlers)
 57			return NULL;
 58	}
 59
 60	hlist_for_each_entry(h, handlers, node)
 61		if (!strcmp(h->xattr_name, name))
 62			return h;
 63
 64	return NULL;
 65}
 66
 67int btrfs_validate_prop(const struct btrfs_inode *inode, const char *name,
 68			const char *value, size_t value_len)
 
 
 
 
 69{
 70	const struct prop_handler *handler;
 
 71
 72	if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
 73		return -EINVAL;
 74
 75	handler = find_prop_handler(name, NULL);
 76	if (!handler)
 77		return -EINVAL;
 78
 79	if (value_len == 0)
 80		return 0;
 81
 82	return handler->validate(inode, value, value_len);
 83}
 84
 85/*
 86 * Check if a property should be ignored (not set) for an inode.
 87 *
 88 * @inode:     The target inode.
 89 * @name:      The property's name.
 90 *
 91 * The caller must be sure the given property name is valid, for example by
 92 * having previously called btrfs_validate_prop().
 93 *
 94 * Returns:    true if the property should be ignored for the given inode
 95 *             false if the property must not be ignored for the given inode
 96 */
 97bool btrfs_ignore_prop(const struct btrfs_inode *inode, const char *name)
 98{
 99	const struct prop_handler *handler;
100
101	handler = find_prop_handler(name, NULL);
102	ASSERT(handler != NULL);
103
104	return handler->ignore(inode);
105}
106
107int btrfs_set_prop(struct btrfs_trans_handle *trans, struct btrfs_inode *inode,
108		   const char *name, const char *value, size_t value_len,
109		   int flags)
110{
111	const struct prop_handler *handler;
112	int ret;
113
114	handler = find_prop_handler(name, NULL);
115	if (!handler)
116		return -EINVAL;
117
118	if (value_len == 0) {
119		ret = btrfs_setxattr(trans, &inode->vfs_inode, handler->xattr_name,
120				     NULL, 0, flags);
121		if (ret)
122			return ret;
123
124		ret = handler->apply(&inode->vfs_inode, NULL, 0);
125		ASSERT(ret == 0);
126
127		return ret;
128	}
129
130	ret = btrfs_setxattr(trans, &inode->vfs_inode, handler->xattr_name, value,
131			     value_len, flags);
 
 
 
132	if (ret)
133		return ret;
134	ret = handler->apply(&inode->vfs_inode, value, value_len);
135	if (ret) {
136		btrfs_setxattr(trans, &inode->vfs_inode, handler->xattr_name, NULL,
137			       0, flags);
138		return ret;
139	}
140
141	set_bit(BTRFS_INODE_HAS_PROPS, &inode->runtime_flags);
142
143	return 0;
144}
145
 
 
 
 
 
 
 
 
 
146static int iterate_object_props(struct btrfs_root *root,
147				struct btrfs_path *path,
148				u64 objectid,
149				void (*iterator)(void *,
150						 const struct prop_handler *,
151						 const char *,
152						 size_t),
153				void *ctx)
154{
155	int ret;
156	char *name_buf = NULL;
157	char *value_buf = NULL;
158	int name_buf_len = 0;
159	int value_buf_len = 0;
160
161	while (1) {
162		struct btrfs_key key;
163		struct btrfs_dir_item *di;
164		struct extent_buffer *leaf;
165		u32 total_len, cur, this_len;
166		int slot;
167		const struct hlist_head *handlers;
168
169		slot = path->slots[0];
170		leaf = path->nodes[0];
171
172		if (slot >= btrfs_header_nritems(leaf)) {
173			ret = btrfs_next_leaf(root, path);
174			if (ret < 0)
175				goto out;
176			else if (ret > 0)
177				break;
178			continue;
179		}
180
181		btrfs_item_key_to_cpu(leaf, &key, slot);
182		if (key.objectid != objectid)
183			break;
184		if (key.type != BTRFS_XATTR_ITEM_KEY)
185			break;
186
187		handlers = find_prop_handlers_by_hash(key.offset);
188		if (!handlers)
189			goto next_slot;
190
191		di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
192		cur = 0;
193		total_len = btrfs_item_size(leaf, slot);
194
195		while (cur < total_len) {
196			u32 name_len = btrfs_dir_name_len(leaf, di);
197			u32 data_len = btrfs_dir_data_len(leaf, di);
198			unsigned long name_ptr, data_ptr;
199			const struct prop_handler *handler;
200
201			this_len = sizeof(*di) + name_len + data_len;
202			name_ptr = (unsigned long)(di + 1);
203			data_ptr = name_ptr + name_len;
204
205			if (name_len <= XATTR_BTRFS_PREFIX_LEN ||
206			    memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
207						 name_ptr,
208						 XATTR_BTRFS_PREFIX_LEN))
209				goto next_dir_item;
210
211			if (name_len >= name_buf_len) {
212				kfree(name_buf);
213				name_buf_len = name_len + 1;
214				name_buf = kmalloc(name_buf_len, GFP_NOFS);
215				if (!name_buf) {
216					ret = -ENOMEM;
217					goto out;
218				}
219			}
220			read_extent_buffer(leaf, name_buf, name_ptr, name_len);
221			name_buf[name_len] = '\0';
222
223			handler = find_prop_handler(name_buf, handlers);
224			if (!handler)
225				goto next_dir_item;
226
227			if (data_len > value_buf_len) {
228				kfree(value_buf);
229				value_buf_len = data_len;
230				value_buf = kmalloc(data_len, GFP_NOFS);
231				if (!value_buf) {
232					ret = -ENOMEM;
233					goto out;
234				}
235			}
236			read_extent_buffer(leaf, value_buf, data_ptr, data_len);
237
238			iterator(ctx, handler, value_buf, data_len);
239next_dir_item:
240			cur += this_len;
241			di = (struct btrfs_dir_item *)((char *) di + this_len);
242		}
243
244next_slot:
245		path->slots[0]++;
246	}
247
248	ret = 0;
249out:
250	btrfs_release_path(path);
251	kfree(name_buf);
252	kfree(value_buf);
253
254	return ret;
255}
256
257static void inode_prop_iterator(void *ctx,
258				const struct prop_handler *handler,
259				const char *value,
260				size_t len)
261{
262	struct inode *inode = ctx;
263	struct btrfs_root *root = BTRFS_I(inode)->root;
264	int ret;
265
266	ret = handler->apply(inode, value, len);
267	if (unlikely(ret))
268		btrfs_warn(root->fs_info,
269			   "error applying prop %s to ino %llu (root %llu): %d",
270			   handler->xattr_name, btrfs_ino(BTRFS_I(inode)),
271			   btrfs_root_id(root), ret);
272	else
273		set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
274}
275
276int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path)
277{
278	struct btrfs_root *root = BTRFS_I(inode)->root;
279	u64 ino = btrfs_ino(BTRFS_I(inode));
 
280
281	return iterate_object_props(root, path, ino, inode_prop_iterator, inode);
 
 
282}
283
284static int prop_compression_validate(const struct btrfs_inode *inode,
285				     const char *value, size_t len)
 
286{
287	if (!btrfs_inode_can_compress(inode))
288		return -EINVAL;
 
 
289
290	if (!value)
 
291		return 0;
292
293	if (btrfs_compress_is_valid_type(value, len))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
294		return 0;
295
296	if ((len == 2 && strncmp("no", value, 2) == 0) ||
297	    (len == 4 && strncmp("none", value, 4) == 0))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
298		return 0;
299
300	return -EINVAL;
301}
302
303static int prop_compression_apply(struct inode *inode, const char *value,
 
304				  size_t len)
305{
306	struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
307	int type;
308
309	/* Reset to defaults */
310	if (len == 0) {
311		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
312		BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
313		BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
314		return 0;
315	}
316
317	/* Set NOCOMPRESS flag */
318	if ((len == 2 && strncmp("no", value, 2) == 0) ||
319	    (len == 4 && strncmp("none", value, 4) == 0)) {
320		BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
321		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
322		BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
323
324		return 0;
325	}
326
327	if (!strncmp("lzo", value, 3)) {
328		type = BTRFS_COMPRESS_LZO;
329		btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
330	} else if (!strncmp("zlib", value, 4)) {
331		type = BTRFS_COMPRESS_ZLIB;
332	} else if (!strncmp("zstd", value, 4)) {
333		type = BTRFS_COMPRESS_ZSTD;
334		btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
335	} else {
336		return -EINVAL;
337	}
338
339	BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
340	BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
341	BTRFS_I(inode)->prop_compress = type;
342
343	return 0;
344}
345
346static bool prop_compression_ignore(const struct btrfs_inode *inode)
347{
348	/*
349	 * Compression only has effect for regular files, and for directories
350	 * we set it just to propagate it to new files created inside them.
351	 * Everything else (symlinks, devices, sockets, fifos) is pointless as
352	 * it will do nothing, so don't waste metadata space on a compression
353	 * xattr for anything that is neither a file nor a directory.
354	 */
355	if (!S_ISREG(inode->vfs_inode.i_mode) &&
356	    !S_ISDIR(inode->vfs_inode.i_mode))
357		return true;
358
359	return false;
360}
361
362static const char *prop_compression_extract(const struct inode *inode)
363{
364	switch (BTRFS_I(inode)->prop_compress) {
365	case BTRFS_COMPRESS_ZLIB:
 
366	case BTRFS_COMPRESS_LZO:
367	case BTRFS_COMPRESS_ZSTD:
368		return btrfs_compress_type2str(BTRFS_I(inode)->prop_compress);
369	default:
370		break;
371	}
372
373	return NULL;
374}
375
376static struct prop_handler prop_handlers[] = {
377	{
378		.xattr_name = XATTR_BTRFS_PREFIX "compression",
379		.validate = prop_compression_validate,
380		.apply = prop_compression_apply,
381		.extract = prop_compression_extract,
382		.ignore = prop_compression_ignore,
383		.inheritable = 1
384	},
385};
386
387int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
388			      struct inode *inode, const struct inode *parent)
389{
390	struct btrfs_root *root = BTRFS_I(inode)->root;
391	struct btrfs_fs_info *fs_info = root->fs_info;
392	int ret;
393	int i;
394	bool need_reserve = false;
395
396	if (!test_bit(BTRFS_INODE_HAS_PROPS,
397		      &BTRFS_I(parent)->runtime_flags))
398		return 0;
399
400	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
401		const struct prop_handler *h = &prop_handlers[i];
402		const char *value;
403		u64 num_bytes = 0;
404
405		if (!h->inheritable)
406			continue;
407
408		if (h->ignore(BTRFS_I(inode)))
409			continue;
410
411		value = h->extract(parent);
412		if (!value)
413			continue;
414
415		/*
416		 * This is not strictly necessary as the property should be
417		 * valid, but in case it isn't, don't propagate it further.
418		 */
419		ret = h->validate(BTRFS_I(inode), value, strlen(value));
420		if (ret)
421			continue;
422
423		/*
424		 * Currently callers should be reserving 1 item for properties,
425		 * since we only have 1 property that we currently support.  If
426		 * we add more in the future we need to try and reserve more
427		 * space for them.  But we should also revisit how we do space
428		 * reservations if we do add more properties in the future.
429		 */
430		if (need_reserve) {
431			num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
432			ret = btrfs_block_rsv_add(fs_info, trans->block_rsv,
433						  num_bytes,
434						  BTRFS_RESERVE_NO_FLUSH);
435			if (ret)
436				return ret;
437		}
438
439		ret = btrfs_setxattr(trans, inode, h->xattr_name, value,
440				     strlen(value), 0);
441		if (!ret) {
442			ret = h->apply(inode, value, strlen(value));
443			if (ret)
444				btrfs_setxattr(trans, inode, h->xattr_name,
445					       NULL, 0, 0);
446			else
447				set_bit(BTRFS_INODE_HAS_PROPS,
448					&BTRFS_I(inode)->runtime_flags);
449		}
450
451		if (need_reserve) {
452			btrfs_block_rsv_release(fs_info, trans->block_rsv,
453					num_bytes, NULL);
454			if (ret)
455				return ret;
456		}
457		need_reserve = true;
458	}
459
460	return 0;
461}
462
463int __init btrfs_props_init(void)
464{
465	int i;
466
467	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
468		struct prop_handler *p = &prop_handlers[i];
469		u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));
470
471		hash_add(prop_handlers_ht, &p->node, h);
472	}
473	return 0;
474}
475
v4.10.11
 
  1/*
  2 * Copyright (C) 2014 Filipe David Borba Manana <fdmanana@gmail.com>
  3 *
  4 * This program is free software; you can redistribute it and/or
  5 * modify it under the terms of the GNU General Public
  6 * License v2 as published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope that it will be useful,
  9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 11 * General Public License for more details.
 12 *
 13 * You should have received a copy of the GNU General Public
 14 * License along with this program; if not, write to the
 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 16 * Boston, MA 021110-1307, USA.
 17 */
 18
 19#include <linux/hashtable.h>
 
 
 20#include "props.h"
 21#include "btrfs_inode.h"
 22#include "hash.h"
 23#include "transaction.h"
 
 24#include "xattr.h"
 25#include "compression.h"
 
 
 
 
 
 26
 27#define BTRFS_PROP_HANDLERS_HT_BITS 8
 28static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
 29
 30struct prop_handler {
 31	struct hlist_node node;
 32	const char *xattr_name;
 33	int (*validate)(const char *value, size_t len);
 
 34	int (*apply)(struct inode *inode, const char *value, size_t len);
 35	const char *(*extract)(struct inode *inode);
 
 36	int inheritable;
 37};
 38
 39static int prop_compression_validate(const char *value, size_t len);
 40static int prop_compression_apply(struct inode *inode,
 41				  const char *value,
 42				  size_t len);
 43static const char *prop_compression_extract(struct inode *inode);
 44
 45static struct prop_handler prop_handlers[] = {
 46	{
 47		.xattr_name = XATTR_BTRFS_PREFIX "compression",
 48		.validate = prop_compression_validate,
 49		.apply = prop_compression_apply,
 50		.extract = prop_compression_extract,
 51		.inheritable = 1
 52	},
 53};
 54
 55void __init btrfs_props_init(void)
 56{
 57	int i;
 58
 59	hash_init(prop_handlers_ht);
 60
 61	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
 62		struct prop_handler *p = &prop_handlers[i];
 63		u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));
 64
 65		hash_add(prop_handlers_ht, &p->node, h);
 66	}
 67}
 68
 69static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
 70{
 71	struct hlist_head *h;
 72
 73	h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
 74	if (hlist_empty(h))
 75		return NULL;
 76
 77	return h;
 78}
 79
 80static const struct prop_handler *
 81find_prop_handler(const char *name,
 82		  const struct hlist_head *handlers)
 83{
 84	struct prop_handler *h;
 85
 86	if (!handlers) {
 87		u64 hash = btrfs_name_hash(name, strlen(name));
 88
 89		handlers = find_prop_handlers_by_hash(hash);
 90		if (!handlers)
 91			return NULL;
 92	}
 93
 94	hlist_for_each_entry(h, handlers, node)
 95		if (!strcmp(h->xattr_name, name))
 96			return h;
 97
 98	return NULL;
 99}
100
101static int __btrfs_set_prop(struct btrfs_trans_handle *trans,
102			    struct inode *inode,
103			    const char *name,
104			    const char *value,
105			    size_t value_len,
106			    int flags)
107{
108	const struct prop_handler *handler;
109	int ret;
110
111	if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
112		return -EINVAL;
113
114	handler = find_prop_handler(name, NULL);
115	if (!handler)
116		return -EINVAL;
117
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
118	if (value_len == 0) {
119		ret = __btrfs_setxattr(trans, inode, handler->xattr_name,
120				       NULL, 0, flags);
121		if (ret)
122			return ret;
123
124		ret = handler->apply(inode, NULL, 0);
125		ASSERT(ret == 0);
126
127		return ret;
128	}
129
130	ret = handler->validate(value, value_len);
131	if (ret)
132		return ret;
133	ret = __btrfs_setxattr(trans, inode, handler->xattr_name,
134			       value, value_len, flags);
135	if (ret)
136		return ret;
137	ret = handler->apply(inode, value, value_len);
138	if (ret) {
139		__btrfs_setxattr(trans, inode, handler->xattr_name,
140				 NULL, 0, flags);
141		return ret;
142	}
143
144	set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
145
146	return 0;
147}
148
149int btrfs_set_prop(struct inode *inode,
150		   const char *name,
151		   const char *value,
152		   size_t value_len,
153		   int flags)
154{
155	return __btrfs_set_prop(NULL, inode, name, value, value_len, flags);
156}
157
158static int iterate_object_props(struct btrfs_root *root,
159				struct btrfs_path *path,
160				u64 objectid,
161				void (*iterator)(void *,
162						 const struct prop_handler *,
163						 const char *,
164						 size_t),
165				void *ctx)
166{
167	int ret;
168	char *name_buf = NULL;
169	char *value_buf = NULL;
170	int name_buf_len = 0;
171	int value_buf_len = 0;
172
173	while (1) {
174		struct btrfs_key key;
175		struct btrfs_dir_item *di;
176		struct extent_buffer *leaf;
177		u32 total_len, cur, this_len;
178		int slot;
179		const struct hlist_head *handlers;
180
181		slot = path->slots[0];
182		leaf = path->nodes[0];
183
184		if (slot >= btrfs_header_nritems(leaf)) {
185			ret = btrfs_next_leaf(root, path);
186			if (ret < 0)
187				goto out;
188			else if (ret > 0)
189				break;
190			continue;
191		}
192
193		btrfs_item_key_to_cpu(leaf, &key, slot);
194		if (key.objectid != objectid)
195			break;
196		if (key.type != BTRFS_XATTR_ITEM_KEY)
197			break;
198
199		handlers = find_prop_handlers_by_hash(key.offset);
200		if (!handlers)
201			goto next_slot;
202
203		di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
204		cur = 0;
205		total_len = btrfs_item_size_nr(leaf, slot);
206
207		while (cur < total_len) {
208			u32 name_len = btrfs_dir_name_len(leaf, di);
209			u32 data_len = btrfs_dir_data_len(leaf, di);
210			unsigned long name_ptr, data_ptr;
211			const struct prop_handler *handler;
212
213			this_len = sizeof(*di) + name_len + data_len;
214			name_ptr = (unsigned long)(di + 1);
215			data_ptr = name_ptr + name_len;
216
217			if (name_len <= XATTR_BTRFS_PREFIX_LEN ||
218			    memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
219						 name_ptr,
220						 XATTR_BTRFS_PREFIX_LEN))
221				goto next_dir_item;
222
223			if (name_len >= name_buf_len) {
224				kfree(name_buf);
225				name_buf_len = name_len + 1;
226				name_buf = kmalloc(name_buf_len, GFP_NOFS);
227				if (!name_buf) {
228					ret = -ENOMEM;
229					goto out;
230				}
231			}
232			read_extent_buffer(leaf, name_buf, name_ptr, name_len);
233			name_buf[name_len] = '\0';
234
235			handler = find_prop_handler(name_buf, handlers);
236			if (!handler)
237				goto next_dir_item;
238
239			if (data_len > value_buf_len) {
240				kfree(value_buf);
241				value_buf_len = data_len;
242				value_buf = kmalloc(data_len, GFP_NOFS);
243				if (!value_buf) {
244					ret = -ENOMEM;
245					goto out;
246				}
247			}
248			read_extent_buffer(leaf, value_buf, data_ptr, data_len);
249
250			iterator(ctx, handler, value_buf, data_len);
251next_dir_item:
252			cur += this_len;
253			di = (struct btrfs_dir_item *)((char *) di + this_len);
254		}
255
256next_slot:
257		path->slots[0]++;
258	}
259
260	ret = 0;
261out:
262	btrfs_release_path(path);
263	kfree(name_buf);
264	kfree(value_buf);
265
266	return ret;
267}
268
269static void inode_prop_iterator(void *ctx,
270				const struct prop_handler *handler,
271				const char *value,
272				size_t len)
273{
274	struct inode *inode = ctx;
275	struct btrfs_root *root = BTRFS_I(inode)->root;
276	int ret;
277
278	ret = handler->apply(inode, value, len);
279	if (unlikely(ret))
280		btrfs_warn(root->fs_info,
281			   "error applying prop %s to ino %llu (root %llu): %d",
282			   handler->xattr_name, btrfs_ino(inode),
283			   root->root_key.objectid, ret);
284	else
285		set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
286}
287
288int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path)
289{
290	struct btrfs_root *root = BTRFS_I(inode)->root;
291	u64 ino = btrfs_ino(inode);
292	int ret;
293
294	ret = iterate_object_props(root, path, ino, inode_prop_iterator, inode);
295
296	return ret;
297}
298
299static int inherit_props(struct btrfs_trans_handle *trans,
300			 struct inode *inode,
301			 struct inode *parent)
302{
303	struct btrfs_root *root = BTRFS_I(inode)->root;
304	struct btrfs_fs_info *fs_info = root->fs_info;
305	int ret;
306	int i;
307
308	if (!test_bit(BTRFS_INODE_HAS_PROPS,
309		      &BTRFS_I(parent)->runtime_flags))
310		return 0;
311
312	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
313		const struct prop_handler *h = &prop_handlers[i];
314		const char *value;
315		u64 num_bytes;
316
317		if (!h->inheritable)
318			continue;
319
320		value = h->extract(parent);
321		if (!value)
322			continue;
323
324		num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
325		ret = btrfs_block_rsv_add(root, trans->block_rsv,
326					  num_bytes, BTRFS_RESERVE_NO_FLUSH);
327		if (ret)
328			goto out;
329		ret = __btrfs_set_prop(trans, inode, h->xattr_name,
330				       value, strlen(value), 0);
331		btrfs_block_rsv_release(fs_info, trans->block_rsv, num_bytes);
332		if (ret)
333			goto out;
334	}
335	ret = 0;
336out:
337	return ret;
338}
339
340int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
341			      struct inode *inode,
342			      struct inode *dir)
343{
344	if (!dir)
345		return 0;
346
347	return inherit_props(trans, inode, dir);
348}
349
350int btrfs_subvol_inherit_props(struct btrfs_trans_handle *trans,
351			       struct btrfs_root *root,
352			       struct btrfs_root *parent_root)
353{
354	struct super_block *sb = root->fs_info->sb;
355	struct btrfs_key key;
356	struct inode *parent_inode, *child_inode;
357	int ret;
358
359	key.objectid = BTRFS_FIRST_FREE_OBJECTID;
360	key.type = BTRFS_INODE_ITEM_KEY;
361	key.offset = 0;
362
363	parent_inode = btrfs_iget(sb, &key, parent_root, NULL);
364	if (IS_ERR(parent_inode))
365		return PTR_ERR(parent_inode);
366
367	child_inode = btrfs_iget(sb, &key, root, NULL);
368	if (IS_ERR(child_inode)) {
369		iput(parent_inode);
370		return PTR_ERR(child_inode);
371	}
372
373	ret = inherit_props(trans, child_inode, parent_inode);
374	iput(child_inode);
375	iput(parent_inode);
376
377	return ret;
378}
379
380static int prop_compression_validate(const char *value, size_t len)
381{
382	if (!strncmp("lzo", value, len))
383		return 0;
384	else if (!strncmp("zlib", value, len))
385		return 0;
386
387	return -EINVAL;
388}
389
390static int prop_compression_apply(struct inode *inode,
391				  const char *value,
392				  size_t len)
393{
 
394	int type;
395
 
396	if (len == 0) {
 
 
 
 
 
 
 
 
 
397		BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
398		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
399		BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
400
401		return 0;
402	}
403
404	if (!strncmp("lzo", value, len))
405		type = BTRFS_COMPRESS_LZO;
406	else if (!strncmp("zlib", value, len))
 
407		type = BTRFS_COMPRESS_ZLIB;
408	else
 
 
 
409		return -EINVAL;
 
410
411	BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
412	BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
413	BTRFS_I(inode)->force_compress = type;
414
415	return 0;
416}
417
418static const char *prop_compression_extract(struct inode *inode)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
419{
420	switch (BTRFS_I(inode)->force_compress) {
421	case BTRFS_COMPRESS_ZLIB:
422		return "zlib";
423	case BTRFS_COMPRESS_LZO:
424		return "lzo";
 
 
 
425	}
426
427	return NULL;
428}
429
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
430