[linux-block.git] / fs / btrfs / props.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2014 Filipe David Borba Manana <fdmanana@gmail.com>
 */

#include <linux/hashtable.h>
#include "messages.h"
#include "props.h"
#include "btrfs_inode.h"
#include "transaction.h"
#include "ctree.h"
#include "xattr.h"
#include "compression.h"
#include "space-info.h"
#include "fs.h"
#include "accessors.h"
#include "super.h"

#define BTRFS_PROP_HANDLERS_HT_BITS 8
static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);

struct prop_handler {
	struct hlist_node node;
	const char *xattr_name;
	int (*validate)(const struct btrfs_inode *inode, const char *value,
			size_t len);
	int (*apply)(struct inode *inode, const char *value, size_t len);
	const char *(*extract)(struct inode *inode);
	bool (*ignore)(const struct btrfs_inode *inode);
	int inheritable;
};

static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
{
	struct hlist_head *h;

	h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
	if (hlist_empty(h))
		return NULL;

	return h;
}

static const struct prop_handler *
find_prop_handler(const char *name,
		  const struct hlist_head *handlers)
{
	struct prop_handler *h;

	if (!handlers) {
		u64 hash = btrfs_name_hash(name, strlen(name));

		handlers = find_prop_handlers_by_hash(hash);
		if (!handlers)
			return NULL;
	}

	hlist_for_each_entry(h, handlers, node)
		if (!strcmp(h->xattr_name, name))
			return h;

	return NULL;
}

int btrfs_validate_prop(const struct btrfs_inode *inode, const char *name,
			const char *value, size_t value_len)
{
	const struct prop_handler *handler;

	if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
		return -EINVAL;

	handler = find_prop_handler(name, NULL);
	if (!handler)
		return -EINVAL;

	if (value_len == 0)
		return 0;

	return handler->validate(inode, value, value_len);
}

/*
 * Check if a property should be ignored (not set) for an inode.
 *
 * @inode:     The target inode.
 * @name:      The property's name.
 *
 * The caller must be sure the given property name is valid, for example by
 * having previously called btrfs_validate_prop().
 *
 * Returns:    true if the property should be ignored for the given inode
 *             false if the property must not be ignored for the given inode
 */
bool btrfs_ignore_prop(const struct btrfs_inode *inode, const char *name)
{
	const struct prop_handler *handler;

	handler = find_prop_handler(name, NULL);
	ASSERT(handler != NULL);

	return handler->ignore(inode);
}

int btrfs_set_prop(struct btrfs_trans_handle *trans, struct inode *inode,
		   const char *name, const char *value, size_t value_len,
		   int flags)
{
	const struct prop_handler *handler;
	int ret;

	handler = find_prop_handler(name, NULL);
	if (!handler)
		return -EINVAL;

	if (value_len == 0) {
		ret = btrfs_setxattr(trans, inode, handler->xattr_name,
				     NULL, 0, flags);
		if (ret)
			return ret;

		ret = handler->apply(inode, NULL, 0);
		ASSERT(ret == 0);

		return ret;
	}

	ret = btrfs_setxattr(trans, inode, handler->xattr_name, value,
			     value_len, flags);
	if (ret)
		return ret;
	ret = handler->apply(inode, value, value_len);
	if (ret) {
		btrfs_setxattr(trans, inode, handler->xattr_name, NULL,
			       0, flags);
		return ret;
	}

	set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);

	return 0;
}

static int iterate_object_props(struct btrfs_root *root,
				struct btrfs_path *path,
				u64 objectid,
				void (*iterator)(void *,
						 const struct prop_handler *,
						 const char *,
						 size_t),
				void *ctx)
{
	int ret;
	char *name_buf = NULL;
	char *value_buf = NULL;
	int name_buf_len = 0;
	int value_buf_len = 0;

	while (1) {
		struct btrfs_key key;
		struct btrfs_dir_item *di;
		struct extent_buffer *leaf;
		u32 total_len, cur, this_len;
		int slot;
		const struct hlist_head *handlers;

		slot = path->slots[0];
		leaf = path->nodes[0];

		if (slot >= btrfs_header_nritems(leaf)) {
			ret = btrfs_next_leaf(root, path);
			if (ret < 0)
				goto out;
			else if (ret > 0)
				break;
			continue;
		}

		btrfs_item_key_to_cpu(leaf, &key, slot);
		if (key.objectid != objectid)
			break;
		if (key.type != BTRFS_XATTR_ITEM_KEY)
			break;

		handlers = find_prop_handlers_by_hash(key.offset);
		if (!handlers)
			goto next_slot;

		di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
		cur = 0;
		total_len = btrfs_item_size(leaf, slot);

		while (cur < total_len) {
			u32 name_len = btrfs_dir_name_len(leaf, di);
			u32 data_len = btrfs_dir_data_len(leaf, di);
			unsigned long name_ptr, data_ptr;
			const struct prop_handler *handler;

			this_len = sizeof(*di) + name_len + data_len;
			name_ptr = (unsigned long)(di + 1);
			data_ptr = name_ptr + name_len;

			if (name_len <= XATTR_BTRFS_PREFIX_LEN ||
			    memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
						 name_ptr,
						 XATTR_BTRFS_PREFIX_LEN))
				goto next_dir_item;

			if (name_len >= name_buf_len) {
				kfree(name_buf);
				name_buf_len = name_len + 1;
				name_buf = kmalloc(name_buf_len, GFP_NOFS);
				if (!name_buf) {
					ret = -ENOMEM;
					goto out;
				}
			}
			read_extent_buffer(leaf, name_buf, name_ptr, name_len);
			name_buf[name_len] = '\0';

			handler = find_prop_handler(name_buf, handlers);
			if (!handler)
				goto next_dir_item;

			if (data_len > value_buf_len) {
				kfree(value_buf);
				value_buf_len = data_len;
				value_buf = kmalloc(data_len, GFP_NOFS);
				if (!value_buf) {
					ret = -ENOMEM;
					goto out;
				}
			}
			read_extent_buffer(leaf, value_buf, data_ptr, data_len);

			iterator(ctx, handler, value_buf, data_len);
next_dir_item:
			cur += this_len;
			di = (struct btrfs_dir_item *)((char *) di + this_len);
		}

next_slot:
		path->slots[0]++;
	}

	ret = 0;
out:
	btrfs_release_path(path);
	kfree(name_buf);
	kfree(value_buf);

	return ret;
}

static void inode_prop_iterator(void *ctx,
				const struct prop_handler *handler,
				const char *value,
				size_t len)
{
	struct inode *inode = ctx;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret;

	ret = handler->apply(inode, value, len);
	if (unlikely(ret))
		btrfs_warn(root->fs_info,
			   "error applying prop %s to ino %llu (root %llu): %d",
			   handler->xattr_name, btrfs_ino(BTRFS_I(inode)),
			   root->root_key.objectid, ret);
	else
		set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
}

int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path)
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
	u64 ino = btrfs_ino(BTRFS_I(inode));

	return iterate_object_props(root, path, ino, inode_prop_iterator, inode);
}

static int prop_compression_validate(const struct btrfs_inode *inode,
				     const char *value, size_t len)
{
	if (!btrfs_inode_can_compress(inode))
		return -EINVAL;

	if (!value)
		return 0;

	if (btrfs_compress_is_valid_type(value, len))
		return 0;

	if ((len == 2 && strncmp("no", value, 2) == 0) ||
	    (len == 4 && strncmp("none", value, 4) == 0))
		return 0;

	return -EINVAL;
}

static int prop_compression_apply(struct inode *inode, const char *value,
				  size_t len)
{
	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
	int type;

	/* Reset to defaults */
	if (len == 0) {
		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
		BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
		BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
		return 0;
	}

	/* Set NOCOMPRESS flag */
	if ((len == 2 && strncmp("no", value, 2) == 0) ||
	    (len == 4 && strncmp("none", value, 4) == 0)) {
		BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
		BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;

		return 0;
	}

	if (!strncmp("lzo", value, 3)) {
		type = BTRFS_COMPRESS_LZO;
		btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
	} else if (!strncmp("zlib", value, 4)) {
		type = BTRFS_COMPRESS_ZLIB;
	} else if (!strncmp("zstd", value, 4)) {
		type = BTRFS_COMPRESS_ZSTD;
		btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
	} else {
		return -EINVAL;
	}

	BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
	BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
	BTRFS_I(inode)->prop_compress = type;

	return 0;
}

static bool prop_compression_ignore(const struct btrfs_inode *inode)
{
	/*
	 * Compression only has effect for regular files, and for directories
	 * we set it just to propagate it to new files created inside them.
	 * Everything else (symlinks, devices, sockets, fifos) is pointless as
	 * it will do nothing, so don't waste metadata space on a compression
	 * xattr for anything that is neither a file nor a directory.
	 */
	if (!S_ISREG(inode->vfs_inode.i_mode) &&
	    !S_ISDIR(inode->vfs_inode.i_mode))
		return true;

	return false;
}

static const char *prop_compression_extract(struct inode *inode)
{
	switch (BTRFS_I(inode)->prop_compress) {
	case BTRFS_COMPRESS_ZLIB:
	case BTRFS_COMPRESS_LZO:
	case BTRFS_COMPRESS_ZSTD:
		return btrfs_compress_type2str(BTRFS_I(inode)->prop_compress);
	default:
		break;
	}

	return NULL;
}

static struct prop_handler prop_handlers[] = {
	{
		.xattr_name = XATTR_BTRFS_PREFIX "compression",
		.validate = prop_compression_validate,
		.apply = prop_compression_apply,
		.extract = prop_compression_extract,
		.ignore = prop_compression_ignore,
		.inheritable = 1
	},
};

int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
			      struct inode *inode, struct inode *parent)
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_fs_info *fs_info = root->fs_info;
	int ret;
	int i;
	bool need_reserve = false;

	if (!test_bit(BTRFS_INODE_HAS_PROPS,
		      &BTRFS_I(parent)->runtime_flags))
		return 0;

	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
		const struct prop_handler *h = &prop_handlers[i];
		const char *value;
		u64 num_bytes = 0;

		if (!h->inheritable)
			continue;

		if (h->ignore(BTRFS_I(inode)))
			continue;

		value = h->extract(parent);
		if (!value)
			continue;

		/*
		 * This is not strictly necessary as the property should be
		 * valid, but in case it isn't, don't propagate it further.
		 */
		ret = h->validate(BTRFS_I(inode), value, strlen(value));
		if (ret)
			continue;

		/*
		 * Currently callers should be reserving 1 item for properties,
		 * since we only have 1 property that we currently support.  If
		 * we add more in the future we need to try and reserve more
		 * space for them.  But we should also revisit how we do space
		 * reservations if we do add more properties in the future.
		 */
		if (need_reserve) {
			num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
			ret = btrfs_block_rsv_add(fs_info, trans->block_rsv,
						  num_bytes,
						  BTRFS_RESERVE_NO_FLUSH);
			if (ret)
				return ret;
		}

		ret = btrfs_setxattr(trans, inode, h->xattr_name, value,
				     strlen(value), 0);
		if (!ret) {
			ret = h->apply(inode, value, strlen(value));
			if (ret)
				btrfs_setxattr(trans, inode, h->xattr_name,
					       NULL, 0, 0);
			else
				set_bit(BTRFS_INODE_HAS_PROPS,
					&BTRFS_I(inode)->runtime_flags);
		}

		if (need_reserve) {
			btrfs_block_rsv_release(fs_info, trans->block_rsv,
					num_bytes, NULL);
			if (ret)
				return ret;
		}
		need_reserve = true;
	}

	return 0;
}

int __init btrfs_props_init(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
		struct prop_handler *p = &prop_handlers[i];
		u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));

		hash_add(prop_handlers_ht, &p->node, h);
	}
	return 0;
}
Commit	Line	Data
c1d7c514	1	// SPDX-License-Identifier: GPL-2.0
63541927 FDBM	2	/*
63541927 FDBM	3	* Copyright (C) 2014 Filipe David Borba Manana <fdmanana@gmail.com>
63541927 FDBM	4	*/
	5
	6	#include <linux/hashtable.h>
9b569ea0	7	#include "messages.h"
63541927 FDBM	8	#include "props.h"
63541927 FDBM	9	#include "btrfs_inode.h"
63541927	10	#include "transaction.h"
9678c543	11	#include "ctree.h"
63541927	12	#include "xattr.h"
ebb8765b	13	#include "compression.h"
f1e5c618	14	#include "space-info.h"
c7f13d42	15	#include "fs.h"
07e81dc9	16	#include "accessors.h"
7f0add25	17	#include "super.h"
63541927 FDBM	18
	19	#define BTRFS_PROP_HANDLERS_HT_BITS 8
	20	static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
	21
	22	struct prop_handler {
	23	struct hlist_node node;
	24	const char *xattr_name;
0e852ab8 CCC	25	int (validate)(const struct btrfs_inode inode, const char *value,
0e852ab8 CCC	26	size_t len);
63541927 FDBM	27	int (apply)(struct inode inode, const char *value, size_t len);
63541927 FDBM	28	const char (extract)(struct inode *inode);
4b73c55f	29	bool (ignore)(const struct btrfs_inode inode);
63541927 FDBM	30	int inheritable;
	31	};
	32
63541927 FDBM	33	static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
	34	{
	35	struct hlist_head *h;
	36
	37	h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
	38	if (hlist_empty(h))
	39	return NULL;
	40
	41	return h;
	42	}
	43
	44	static const struct prop_handler *
	45	find_prop_handler(const char *name,
	46	const struct hlist_head *handlers)
	47	{
	48	struct prop_handler *h;
	49
	50	if (!handlers) {
	51	u64 hash = btrfs_name_hash(name, strlen(name));
	52
	53	handlers = find_prop_handlers_by_hash(hash);
	54	if (!handlers)
	55	return NULL;
	56	}
	57
	58	hlist_for_each_entry(h, handlers, node)
	59	if (!strcmp(h->xattr_name, name))
	60	return h;
	61
	62	return NULL;
	63	}
	64
0e852ab8 CCC	65	int btrfs_validate_prop(const struct btrfs_inode inode, const char name,
0e852ab8 CCC	66	const char *value, size_t value_len)
f22125e5 AJ	67	{
	68	const struct prop_handler *handler;
	69
	70	if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
	71	return -EINVAL;
	72
	73	handler = find_prop_handler(name, NULL);
	74	if (!handler)
	75	return -EINVAL;
	76
	77	if (value_len == 0)
	78	return 0;
	79
0e852ab8	80	return handler->validate(inode, value, value_len);
f22125e5 AJ	81	}
f22125e5 AJ	82
4b73c55f FM	83	/*
	84	* Check if a property should be ignored (not set) for an inode.
	85	*
	86	* @inode: The target inode.
	87	* @name: The property's name.
	88	*
	89	* The caller must be sure the given property name is valid, for example by
	90	* having previously called btrfs_validate_prop().
	91	*
	92	* Returns: true if the property should be ignored for the given inode
	93	* false if the property must not be ignored for the given inode
	94	*/
	95	bool btrfs_ignore_prop(const struct btrfs_inode inode, const char name)
	96	{
	97	const struct prop_handler *handler;
	98
	99	handler = find_prop_handler(name, NULL);
	100	ASSERT(handler != NULL);
	101
	102	return handler->ignore(inode);
	103	}
	104
cd31af15 AJ	105	int btrfs_set_prop(struct btrfs_trans_handle trans, struct inode inode,
	106	const char name, const char value, size_t value_len,
	107	int flags)
63541927 FDBM	108	{
	109	const struct prop_handler *handler;
	110	int ret;
	111
63541927 FDBM	112	handler = find_prop_handler(name, NULL);
	113	if (!handler)
	114	return -EINVAL;
	115
	116	if (value_len == 0) {
da9b6ec8 AJ	117	ret = btrfs_setxattr(trans, inode, handler->xattr_name,
da9b6ec8 AJ	118	NULL, 0, flags);
63541927 FDBM	119	if (ret)
	120	return ret;
	121
	122	ret = handler->apply(inode, NULL, 0);
	123	ASSERT(ret == 0);
	124
	125	return ret;
	126	}
	127
da9b6ec8 AJ	128	ret = btrfs_setxattr(trans, inode, handler->xattr_name, value,
da9b6ec8 AJ	129	value_len, flags);
63541927 FDBM	130	if (ret)
	131	return ret;
	132	ret = handler->apply(inode, value, value_len);
	133	if (ret) {
da9b6ec8 AJ	134	btrfs_setxattr(trans, inode, handler->xattr_name, NULL,
da9b6ec8 AJ	135	0, flags);
63541927 FDBM	136	return ret;
	137	}
	138
	139	set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
	140
	141	return 0;
	142	}
	143
63541927 FDBM	144	static int iterate_object_props(struct btrfs_root *root,
	145	struct btrfs_path *path,
	146	u64 objectid,
	147	void (iterator)(void ,
	148	const struct prop_handler *,
	149	const char *,
	150	size_t),
	151	void *ctx)
	152	{
	153	int ret;
	154	char *name_buf = NULL;
	155	char *value_buf = NULL;
	156	int name_buf_len = 0;
	157	int value_buf_len = 0;
	158
	159	while (1) {
	160	struct btrfs_key key;
	161	struct btrfs_dir_item *di;
	162	struct extent_buffer *leaf;
	163	u32 total_len, cur, this_len;
	164	int slot;
	165	const struct hlist_head *handlers;
	166
	167	slot = path->slots[0];
	168	leaf = path->nodes[0];
	169
	170	if (slot >= btrfs_header_nritems(leaf)) {
	171	ret = btrfs_next_leaf(root, path);
	172	if (ret < 0)
	173	goto out;
	174	else if (ret > 0)
	175	break;
	176	continue;
	177	}
	178
	179	btrfs_item_key_to_cpu(leaf, &key, slot);
	180	if (key.objectid != objectid)
	181	break;
	182	if (key.type != BTRFS_XATTR_ITEM_KEY)
	183	break;
	184
	185	handlers = find_prop_handlers_by_hash(key.offset);
	186	if (!handlers)
	187	goto next_slot;
	188
	189	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
	190	cur = 0;
3212fa14	191	total_len = btrfs_item_size(leaf, slot);
63541927 FDBM	192
	193	while (cur < total_len) {
	194	u32 name_len = btrfs_dir_name_len(leaf, di);
	195	u32 data_len = btrfs_dir_data_len(leaf, di);
	196	unsigned long name_ptr, data_ptr;
	197	const struct prop_handler *handler;
	198
	199	this_len = sizeof(*di) + name_len + data_len;
	200	name_ptr = (unsigned long)(di + 1);
	201	data_ptr = name_ptr + name_len;
	202
	203	if (name_len <= XATTR_BTRFS_PREFIX_LEN \|\|
	204	memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
	205	name_ptr,
	206	XATTR_BTRFS_PREFIX_LEN))
	207	goto next_dir_item;
	208
	209	if (name_len >= name_buf_len) {
	210	kfree(name_buf);
	211	name_buf_len = name_len + 1;
	212	name_buf = kmalloc(name_buf_len, GFP_NOFS);
	213	if (!name_buf) {
	214	ret = -ENOMEM;
	215	goto out;
	216	}
	217	}
	218	read_extent_buffer(leaf, name_buf, name_ptr, name_len);
	219	name_buf[name_len] = '\0';
	220
	221	handler = find_prop_handler(name_buf, handlers);
	222	if (!handler)
	223	goto next_dir_item;
	224
	225	if (data_len > value_buf_len) {
	226	kfree(value_buf);
	227	value_buf_len = data_len;
	228	value_buf = kmalloc(data_len, GFP_NOFS);
	229	if (!value_buf) {
	230	ret = -ENOMEM;
	231	goto out;
	232	}
	233	}
	234	read_extent_buffer(leaf, value_buf, data_ptr, data_len);
	235
	236	iterator(ctx, handler, value_buf, data_len);
	237	next_dir_item:
	238	cur += this_len;
	239	di = (struct btrfs_dir_item )((char ) di + this_len);
	240	}
	241
	242	next_slot:
	243	path->slots[0]++;
	244	}
	245
	246	ret = 0;
	247	out:
	248	btrfs_release_path(path);
	249	kfree(name_buf);
	250	kfree(value_buf);
	251
	252	return ret;
	253	}
	254
	255	static void inode_prop_iterator(void *ctx,
256	const struct prop_handler *handler,
257	const char *value,
258	size_t len)
259	{
260	struct inode *inode = ctx;
261	struct btrfs_root *root = BTRFS_I(inode)->root;
262	int ret;
263
264	ret = handler->apply(inode, value, len);
265	if (unlikely(ret))
266	btrfs_warn(root->fs_info,
267	"error applying prop %s to ino %llu (root %llu): %d",
4a0cc7ca	268	handler->xattr_name, btrfs_ino(BTRFS_I(inode)),
63541927 FDBM	269	root->root_key.objectid, ret);
	270	else
	271	set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
	272	}
	273
	274	int btrfs_load_inode_props(struct inode inode, struct btrfs_path path)
	275	{
	276	struct btrfs_root *root = BTRFS_I(inode)->root;
4a0cc7ca	277	u64 ino = btrfs_ino(BTRFS_I(inode));
63541927	278
bd64f622	279	return iterate_object_props(root, path, ino, inode_prop_iterator, inode);
63541927 FDBM	280	}
63541927 FDBM	281
0e852ab8 CCC	282	static int prop_compression_validate(const struct btrfs_inode *inode,
0e852ab8 CCC	283	const char *value, size_t len)
3dcf96c7	284	{
0e852ab8 CCC	285	if (!btrfs_inode_can_compress(inode))
	286	return -EINVAL;
	287
3dcf96c7 AJ	288	if (!value)
	289	return 0;
	290
aa53e3bf	291	if (btrfs_compress_is_valid_type(value, len))
3dcf96c7 AJ	292	return 0;
3dcf96c7 AJ	293
5548c8c6 DS	294	if ((len == 2 && strncmp("no", value, 2) == 0) \|\|
	295	(len == 4 && strncmp("none", value, 4) == 0))
	296	return 0;
	297
3dcf96c7 AJ	298	return -EINVAL;
	299	}
	300
	301	static int prop_compression_apply(struct inode inode, const char value,
	302	size_t len)
	303	{
	304	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
	305	int type;
	306
5548c8c6	307	/* Reset to defaults */
3dcf96c7	308	if (len == 0) {
5548c8c6 DS	309	BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
	310	BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
	311	BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
	312	return 0;
	313	}
	314
	315	/* Set NOCOMPRESS flag */
	316	if ((len == 2 && strncmp("no", value, 2) == 0) \|\|
	317	(len == 4 && strncmp("none", value, 4) == 0)) {
3dcf96c7 AJ	318	BTRFS_I(inode)->flags \|= BTRFS_INODE_NOCOMPRESS;
	319	BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
	320	BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
	321
	322	return 0;
	323	}
	324
	325	if (!strncmp("lzo", value, 3)) {
	326	type = BTRFS_COMPRESS_LZO;
	327	btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
	328	} else if (!strncmp("zlib", value, 4)) {
	329	type = BTRFS_COMPRESS_ZLIB;
	330	} else if (!strncmp("zstd", value, 4)) {
	331	type = BTRFS_COMPRESS_ZSTD;
	332	btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
	333	} else {
	334	return -EINVAL;
	335	}
	336
	337	BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
	338	BTRFS_I(inode)->flags \|= BTRFS_INODE_COMPRESS;
	339	BTRFS_I(inode)->prop_compress = type;
	340
	341	return 0;
	342	}
	343
4b73c55f FM	344	static bool prop_compression_ignore(const struct btrfs_inode *inode)
	345	{
	346	/*
	347	* Compression only has effect for regular files, and for directories
	348	* we set it just to propagate it to new files created inside them.
	349	* Everything else (symlinks, devices, sockets, fifos) is pointless as
	350	* it will do nothing, so don't waste metadata space on a compression
	351	* xattr for anything that is neither a file nor a directory.
	352	*/
	353	if (!S_ISREG(inode->vfs_inode.i_mode) &&
	354	!S_ISDIR(inode->vfs_inode.i_mode))
	355	return true;
	356
	357	return false;
	358	}
	359
3dcf96c7 AJ	360	static const char prop_compression_extract(struct inode inode)
	361	{
	362	switch (BTRFS_I(inode)->prop_compress) {
	363	case BTRFS_COMPRESS_ZLIB:
	364	case BTRFS_COMPRESS_LZO:
	365	case BTRFS_COMPRESS_ZSTD:
	366	return btrfs_compress_type2str(BTRFS_I(inode)->prop_compress);
	367	default:
	368	break;
	369	}
	370
	371	return NULL;
	372	}
	373
	374	static struct prop_handler prop_handlers[] = {
	375	{
	376	.xattr_name = XATTR_BTRFS_PREFIX "compression",
	377	.validate = prop_compression_validate,
	378	.apply = prop_compression_apply,
	379	.extract = prop_compression_extract,
4b73c55f	380	.ignore = prop_compression_ignore,
3dcf96c7 AJ	381	.inheritable = 1
	382	},
	383	};
	384
caae78e0 OS	385	int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
caae78e0 OS	386	struct inode inode, struct inode parent)
63541927	387	{
63541927	388	struct btrfs_root *root = BTRFS_I(inode)->root;
2ff7e61e	389	struct btrfs_fs_info *fs_info = root->fs_info;
63541927	390	int ret;
619ed392	391	int i;
d7400ee1	392	bool need_reserve = false;
63541927 FDBM	393
	394	if (!test_bit(BTRFS_INODE_HAS_PROPS,
	395	&BTRFS_I(parent)->runtime_flags))
	396	return 0;
	397
619ed392 BL	398	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
619ed392 BL	399	const struct prop_handler *h = &prop_handlers[i];
63541927	400	const char *value;
6c64460c	401	u64 num_bytes = 0;
63541927 FDBM	402
	403	if (!h->inheritable)
	404	continue;
	405
4b73c55f FM	406	if (h->ignore(BTRFS_I(inode)))
	407	continue;
	408
63541927 FDBM	409	value = h->extract(parent);
	410	if (!value)
	411	continue;
	412
8b4d1efc AJ	413	/*
8b4d1efc AJ	414	* This is not strictly necessary as the property should be
1a9fd417	415	* valid, but in case it isn't, don't propagate it further.
8b4d1efc	416	*/
0e852ab8	417	ret = h->validate(BTRFS_I(inode), value, strlen(value));
8b4d1efc AJ	418	if (ret)
	419	continue;
	420
d7400ee1 JB	421	/*
	422	* Currently callers should be reserving 1 item for properties,
	423	* since we only have 1 property that we currently support. If
	424	* we add more in the future we need to try and reserve more
	425	* space for them. But we should also revisit how we do space
	426	* reservations if we do add more properties in the future.
	427	*/
	428	if (need_reserve) {
2bd36e7b	429	num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
9270501c JB	430	ret = btrfs_block_rsv_add(fs_info, trans->block_rsv,
	431	num_bytes,
	432	BTRFS_RESERVE_NO_FLUSH);
d7400ee1 JB	433	if (ret)
	434	return ret;
	435	}
8b4d1efc	436
04e6863b AJ	437	ret = btrfs_setxattr(trans, inode, h->xattr_name, value,
04e6863b AJ	438	strlen(value), 0);
8b4d1efc AJ	439	if (!ret) {
	440	ret = h->apply(inode, value, strlen(value));
	441	if (ret)
04e6863b AJ	442	btrfs_setxattr(trans, inode, h->xattr_name,
04e6863b AJ	443	NULL, 0, 0);
8b4d1efc AJ	444	else
	445	set_bit(BTRFS_INODE_HAS_PROPS,
	446	&BTRFS_I(inode)->runtime_flags);
	447	}
	448
d7400ee1 JB	449	if (need_reserve) {
d7400ee1 JB	450	btrfs_block_rsv_release(fs_info, trans->block_rsv,
63f018be	451	num_bytes, NULL);
d7400ee1 JB	452	if (ret)
	453	return ret;
	454	}
	455	need_reserve = true;
63541927	456	}
8b4d1efc AJ	457
8b4d1efc AJ	458	return 0;
63541927 FDBM	459	}
63541927 FDBM	460
5565b8e0	461	int __init btrfs_props_init(void)
63541927	462	{
3dcf96c7	463	int i;
63541927	464
3dcf96c7 AJ	465	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
	466	struct prop_handler *p = &prop_handlers[i];
	467	u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));
63541927	468
3dcf96c7	469	hash_add(prop_handlers_ht, &p->node, h);
63541927	470	}
5565b8e0	471	return 0;
63541927	472	}
e8c9f186	473