[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 "props.h"
#include "btrfs_inode.h"
#include "transaction.h"
#include "ctree.h"
#include "xattr.h"
#include "compression.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));
	int ret;

	ret = iterate_object_props(root, path, ino, inode_prop_iterator, inode);

	return ret;
}

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
	},
};

static int 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 btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
			      struct inode *inode,
			      struct inode *dir)
{
	if (!dir)
		return 0;

	return inherit_props(trans, inode, dir);
}

int btrfs_subvol_inherit_props(struct btrfs_trans_handle *trans,
			       struct btrfs_root *root,
			       struct btrfs_root *parent_root)
{
	struct super_block *sb = root->fs_info->sb;
	struct inode *parent_inode, *child_inode;
	int ret;

	parent_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, parent_root);
	if (IS_ERR(parent_inode))
		return PTR_ERR(parent_inode);

	child_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, root);
	if (IS_ERR(child_inode)) {
		iput(parent_inode);
		return PTR_ERR(child_inode);
	}

	ret = inherit_props(trans, child_inode, parent_inode);
	iput(child_inode);
	iput(parent_inode);

	return ret;
}

void __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);
	}
}
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>
	7	#include "props.h"
	8	#include "btrfs_inode.h"
63541927	9	#include "transaction.h"
9678c543	10	#include "ctree.h"
63541927	11	#include "xattr.h"
ebb8765b	12	#include "compression.h"
63541927 FDBM	13
	14	#define BTRFS_PROP_HANDLERS_HT_BITS 8
	15	static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
	16
	17	struct prop_handler {
	18	struct hlist_node node;
	19	const char *xattr_name;
0e852ab8 CCC	20	int (validate)(const struct btrfs_inode inode, const char *value,
0e852ab8 CCC	21	size_t len);
63541927 FDBM	22	int (apply)(struct inode inode, const char *value, size_t len);
63541927 FDBM	23	const char (extract)(struct inode *inode);
4b73c55f	24	bool (ignore)(const struct btrfs_inode inode);
63541927 FDBM	25	int inheritable;
	26	};
	27
63541927 FDBM	28	static const struct hlist_head *find_prop_handlers_by_hash(const u64 hash)
	29	{
	30	struct hlist_head *h;
	31
	32	h = &prop_handlers_ht[hash_min(hash, BTRFS_PROP_HANDLERS_HT_BITS)];
	33	if (hlist_empty(h))
	34	return NULL;
	35
	36	return h;
	37	}
	38
	39	static const struct prop_handler *
	40	find_prop_handler(const char *name,
	41	const struct hlist_head *handlers)
	42	{
	43	struct prop_handler *h;
	44
	45	if (!handlers) {
	46	u64 hash = btrfs_name_hash(name, strlen(name));
	47
	48	handlers = find_prop_handlers_by_hash(hash);
	49	if (!handlers)
	50	return NULL;
	51	}
	52
	53	hlist_for_each_entry(h, handlers, node)
	54	if (!strcmp(h->xattr_name, name))
	55	return h;
	56
	57	return NULL;
	58	}
	59
0e852ab8 CCC	60	int btrfs_validate_prop(const struct btrfs_inode inode, const char name,
0e852ab8 CCC	61	const char *value, size_t value_len)
f22125e5 AJ	62	{
	63	const struct prop_handler *handler;
	64
	65	if (strlen(name) <= XATTR_BTRFS_PREFIX_LEN)
	66	return -EINVAL;
	67
	68	handler = find_prop_handler(name, NULL);
	69	if (!handler)
	70	return -EINVAL;
	71
	72	if (value_len == 0)
	73	return 0;
	74
0e852ab8	75	return handler->validate(inode, value, value_len);
f22125e5 AJ	76	}
f22125e5 AJ	77
4b73c55f FM	78	/*
	79	* Check if a property should be ignored (not set) for an inode.
	80	*
	81	* @inode: The target inode.
	82	* @name: The property's name.
	83	*
	84	* The caller must be sure the given property name is valid, for example by
	85	* having previously called btrfs_validate_prop().
	86	*
	87	* Returns: true if the property should be ignored for the given inode
	88	* false if the property must not be ignored for the given inode
	89	*/
	90	bool btrfs_ignore_prop(const struct btrfs_inode inode, const char name)
	91	{
	92	const struct prop_handler *handler;
	93
	94	handler = find_prop_handler(name, NULL);
	95	ASSERT(handler != NULL);
	96
	97	return handler->ignore(inode);
	98	}
	99
cd31af15 AJ	100	int btrfs_set_prop(struct btrfs_trans_handle trans, struct inode inode,
	101	const char name, const char value, size_t value_len,
	102	int flags)
63541927 FDBM	103	{
	104	const struct prop_handler *handler;
	105	int ret;
	106
63541927 FDBM	107	handler = find_prop_handler(name, NULL);
	108	if (!handler)
	109	return -EINVAL;
	110
	111	if (value_len == 0) {
da9b6ec8 AJ	112	ret = btrfs_setxattr(trans, inode, handler->xattr_name,
da9b6ec8 AJ	113	NULL, 0, flags);
63541927 FDBM	114	if (ret)
	115	return ret;
	116
	117	ret = handler->apply(inode, NULL, 0);
	118	ASSERT(ret == 0);
	119
	120	return ret;
	121	}
	122
da9b6ec8 AJ	123	ret = btrfs_setxattr(trans, inode, handler->xattr_name, value,
da9b6ec8 AJ	124	value_len, flags);
63541927 FDBM	125	if (ret)
	126	return ret;
	127	ret = handler->apply(inode, value, value_len);
	128	if (ret) {
da9b6ec8 AJ	129	btrfs_setxattr(trans, inode, handler->xattr_name, NULL,
da9b6ec8 AJ	130	0, flags);
63541927 FDBM	131	return ret;
	132	}
	133
	134	set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
	135
	136	return 0;
	137	}
	138
63541927 FDBM	139	static int iterate_object_props(struct btrfs_root *root,
	140	struct btrfs_path *path,
	141	u64 objectid,
	142	void (iterator)(void ,
	143	const struct prop_handler *,
	144	const char *,
	145	size_t),
	146	void *ctx)
	147	{
	148	int ret;
	149	char *name_buf = NULL;
	150	char *value_buf = NULL;
	151	int name_buf_len = 0;
	152	int value_buf_len = 0;
	153
	154	while (1) {
	155	struct btrfs_key key;
	156	struct btrfs_dir_item *di;
	157	struct extent_buffer *leaf;
	158	u32 total_len, cur, this_len;
	159	int slot;
	160	const struct hlist_head *handlers;
	161
	162	slot = path->slots[0];
	163	leaf = path->nodes[0];
	164
	165	if (slot >= btrfs_header_nritems(leaf)) {
	166	ret = btrfs_next_leaf(root, path);
	167	if (ret < 0)
	168	goto out;
	169	else if (ret > 0)
	170	break;
	171	continue;
	172	}
	173
	174	btrfs_item_key_to_cpu(leaf, &key, slot);
	175	if (key.objectid != objectid)
	176	break;
	177	if (key.type != BTRFS_XATTR_ITEM_KEY)
	178	break;
	179
	180	handlers = find_prop_handlers_by_hash(key.offset);
	181	if (!handlers)
	182	goto next_slot;
	183
	184	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
	185	cur = 0;
3212fa14	186	total_len = btrfs_item_size(leaf, slot);
63541927 FDBM	187
	188	while (cur < total_len) {
	189	u32 name_len = btrfs_dir_name_len(leaf, di);
	190	u32 data_len = btrfs_dir_data_len(leaf, di);
	191	unsigned long name_ptr, data_ptr;
	192	const struct prop_handler *handler;
	193
	194	this_len = sizeof(*di) + name_len + data_len;
	195	name_ptr = (unsigned long)(di + 1);
	196	data_ptr = name_ptr + name_len;
	197
	198	if (name_len <= XATTR_BTRFS_PREFIX_LEN \|\|
	199	memcmp_extent_buffer(leaf, XATTR_BTRFS_PREFIX,
	200	name_ptr,
	201	XATTR_BTRFS_PREFIX_LEN))
	202	goto next_dir_item;
	203
	204	if (name_len >= name_buf_len) {
	205	kfree(name_buf);
	206	name_buf_len = name_len + 1;
	207	name_buf = kmalloc(name_buf_len, GFP_NOFS);
	208	if (!name_buf) {
	209	ret = -ENOMEM;
	210	goto out;
	211	}
	212	}
	213	read_extent_buffer(leaf, name_buf, name_ptr, name_len);
	214	name_buf[name_len] = '\0';
	215
	216	handler = find_prop_handler(name_buf, handlers);
	217	if (!handler)
	218	goto next_dir_item;
	219
	220	if (data_len > value_buf_len) {
	221	kfree(value_buf);
	222	value_buf_len = data_len;
	223	value_buf = kmalloc(data_len, GFP_NOFS);
	224	if (!value_buf) {
	225	ret = -ENOMEM;
	226	goto out;
	227	}
	228	}
	229	read_extent_buffer(leaf, value_buf, data_ptr, data_len);
	230
	231	iterator(ctx, handler, value_buf, data_len);
	232	next_dir_item:
	233	cur += this_len;
	234	di = (struct btrfs_dir_item )((char ) di + this_len);
	235	}
	236
	237	next_slot:
	238	path->slots[0]++;
	239	}
	240
	241	ret = 0;
	242	out:
	243	btrfs_release_path(path);
	244	kfree(name_buf);
	245	kfree(value_buf);
	246
	247	return ret;
	248	}
	249
	250	static void inode_prop_iterator(void *ctx,
251	const struct prop_handler *handler,
252	const char *value,
253	size_t len)
254	{
255	struct inode *inode = ctx;
256	struct btrfs_root *root = BTRFS_I(inode)->root;
257	int ret;
258
259	ret = handler->apply(inode, value, len);
260	if (unlikely(ret))
261	btrfs_warn(root->fs_info,
262	"error applying prop %s to ino %llu (root %llu): %d",
4a0cc7ca	263	handler->xattr_name, btrfs_ino(BTRFS_I(inode)),
63541927 FDBM	264	root->root_key.objectid, ret);
	265	else
	266	set_bit(BTRFS_INODE_HAS_PROPS, &BTRFS_I(inode)->runtime_flags);
	267	}
	268
	269	int btrfs_load_inode_props(struct inode inode, struct btrfs_path path)
	270	{
	271	struct btrfs_root *root = BTRFS_I(inode)->root;
4a0cc7ca	272	u64 ino = btrfs_ino(BTRFS_I(inode));
63541927 FDBM	273	int ret;
	274
	275	ret = iterate_object_props(root, path, ino, inode_prop_iterator, inode);
	276
	277	return ret;
	278	}
	279
0e852ab8 CCC	280	static int prop_compression_validate(const struct btrfs_inode *inode,
0e852ab8 CCC	281	const char *value, size_t len)
3dcf96c7	282	{
0e852ab8 CCC	283	if (!btrfs_inode_can_compress(inode))
	284	return -EINVAL;
	285
3dcf96c7 AJ	286	if (!value)
	287	return 0;
	288
aa53e3bf	289	if (btrfs_compress_is_valid_type(value, len))
3dcf96c7 AJ	290	return 0;
3dcf96c7 AJ	291
5548c8c6 DS	292	if ((len == 2 && strncmp("no", value, 2) == 0) \|\|
	293	(len == 4 && strncmp("none", value, 4) == 0))
	294	return 0;
	295
3dcf96c7 AJ	296	return -EINVAL;
	297	}
	298
	299	static int prop_compression_apply(struct inode inode, const char value,
	300	size_t len)
	301	{
	302	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
	303	int type;
	304
5548c8c6	305	/* Reset to defaults */
3dcf96c7	306	if (len == 0) {
5548c8c6 DS	307	BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
	308	BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
	309	BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
	310	return 0;
	311	}
	312
	313	/* Set NOCOMPRESS flag */
	314	if ((len == 2 && strncmp("no", value, 2) == 0) \|\|
	315	(len == 4 && strncmp("none", value, 4) == 0)) {
3dcf96c7 AJ	316	BTRFS_I(inode)->flags \|= BTRFS_INODE_NOCOMPRESS;
	317	BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
	318	BTRFS_I(inode)->prop_compress = BTRFS_COMPRESS_NONE;
	319
	320	return 0;
	321	}
	322
	323	if (!strncmp("lzo", value, 3)) {
	324	type = BTRFS_COMPRESS_LZO;
	325	btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
	326	} else if (!strncmp("zlib", value, 4)) {
	327	type = BTRFS_COMPRESS_ZLIB;
	328	} else if (!strncmp("zstd", value, 4)) {
	329	type = BTRFS_COMPRESS_ZSTD;
	330	btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
	331	} else {
	332	return -EINVAL;
	333	}
	334
	335	BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
	336	BTRFS_I(inode)->flags \|= BTRFS_INODE_COMPRESS;
	337	BTRFS_I(inode)->prop_compress = type;
	338
	339	return 0;
	340	}
	341
4b73c55f FM	342	static bool prop_compression_ignore(const struct btrfs_inode *inode)
	343	{
	344	/*
	345	* Compression only has effect for regular files, and for directories
	346	* we set it just to propagate it to new files created inside them.
	347	* Everything else (symlinks, devices, sockets, fifos) is pointless as
	348	* it will do nothing, so don't waste metadata space on a compression
	349	* xattr for anything that is neither a file nor a directory.
	350	*/
	351	if (!S_ISREG(inode->vfs_inode.i_mode) &&
	352	!S_ISDIR(inode->vfs_inode.i_mode))
	353	return true;
	354
	355	return false;
	356	}
	357
3dcf96c7 AJ	358	static const char prop_compression_extract(struct inode inode)
	359	{
	360	switch (BTRFS_I(inode)->prop_compress) {
	361	case BTRFS_COMPRESS_ZLIB:
	362	case BTRFS_COMPRESS_LZO:
	363	case BTRFS_COMPRESS_ZSTD:
	364	return btrfs_compress_type2str(BTRFS_I(inode)->prop_compress);
	365	default:
	366	break;
	367	}
	368
	369	return NULL;
	370	}
	371
	372	static struct prop_handler prop_handlers[] = {
	373	{
	374	.xattr_name = XATTR_BTRFS_PREFIX "compression",
	375	.validate = prop_compression_validate,
	376	.apply = prop_compression_apply,
	377	.extract = prop_compression_extract,
4b73c55f	378	.ignore = prop_compression_ignore,
3dcf96c7 AJ	379	.inheritable = 1
	380	},
	381	};
	382
63541927 FDBM	383	static int inherit_props(struct btrfs_trans_handle *trans,
	384	struct inode *inode,
	385	struct inode *parent)
	386	{
63541927	387	struct btrfs_root *root = BTRFS_I(inode)->root;
2ff7e61e	388	struct btrfs_fs_info *fs_info = root->fs_info;
63541927	389	int ret;
619ed392	390	int i;
d7400ee1	391	bool need_reserve = false;
63541927 FDBM	392
	393	if (!test_bit(BTRFS_INODE_HAS_PROPS,
	394	&BTRFS_I(parent)->runtime_flags))
	395	return 0;
	396
619ed392 BL	397	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
619ed392 BL	398	const struct prop_handler *h = &prop_handlers[i];
63541927	399	const char *value;
6c64460c	400	u64 num_bytes = 0;
63541927 FDBM	401
	402	if (!h->inheritable)
	403	continue;
	404
4b73c55f FM	405	if (h->ignore(BTRFS_I(inode)))
	406	continue;
	407
63541927 FDBM	408	value = h->extract(parent);
	409	if (!value)
	410	continue;
	411
8b4d1efc AJ	412	/*
8b4d1efc AJ	413	* This is not strictly necessary as the property should be
1a9fd417	414	* valid, but in case it isn't, don't propagate it further.
8b4d1efc	415	*/
0e852ab8	416	ret = h->validate(BTRFS_I(inode), value, strlen(value));
8b4d1efc AJ	417	if (ret)
	418	continue;
	419
d7400ee1 JB	420	/*
	421	* Currently callers should be reserving 1 item for properties,
	422	* since we only have 1 property that we currently support. If
	423	* we add more in the future we need to try and reserve more
	424	* space for them. But we should also revisit how we do space
	425	* reservations if we do add more properties in the future.
	426	*/
	427	if (need_reserve) {
2bd36e7b	428	num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
9270501c JB	429	ret = btrfs_block_rsv_add(fs_info, trans->block_rsv,
	430	num_bytes,
	431	BTRFS_RESERVE_NO_FLUSH);
d7400ee1 JB	432	if (ret)
	433	return ret;
	434	}
8b4d1efc	435
04e6863b AJ	436	ret = btrfs_setxattr(trans, inode, h->xattr_name, value,
04e6863b AJ	437	strlen(value), 0);
8b4d1efc AJ	438	if (!ret) {
	439	ret = h->apply(inode, value, strlen(value));
	440	if (ret)
04e6863b AJ	441	btrfs_setxattr(trans, inode, h->xattr_name,
04e6863b AJ	442	NULL, 0, 0);
8b4d1efc AJ	443	else
	444	set_bit(BTRFS_INODE_HAS_PROPS,
	445	&BTRFS_I(inode)->runtime_flags);
	446	}
	447
d7400ee1 JB	448	if (need_reserve) {
d7400ee1 JB	449	btrfs_block_rsv_release(fs_info, trans->block_rsv,
63f018be	450	num_bytes, NULL);
d7400ee1 JB	451	if (ret)
	452	return ret;
	453	}
	454	need_reserve = true;
63541927	455	}
8b4d1efc AJ	456
8b4d1efc AJ	457	return 0;
63541927 FDBM	458	}
	459
	460	int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans,
	461	struct inode *inode,
	462	struct inode *dir)
	463	{
	464	if (!dir)
	465	return 0;
	466
	467	return inherit_props(trans, inode, dir);
	468	}
	469
	470	int btrfs_subvol_inherit_props(struct btrfs_trans_handle *trans,
	471	struct btrfs_root *root,
	472	struct btrfs_root *parent_root)
	473	{
bd6c57dd	474	struct super_block *sb = root->fs_info->sb;
63541927 FDBM	475	struct inode parent_inode, child_inode;
	476	int ret;
	477
0202e83f	478	parent_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, parent_root);
63541927 FDBM	479	if (IS_ERR(parent_inode))
	480	return PTR_ERR(parent_inode);
	481
0202e83f	482	child_inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, root);
63541927 FDBM	483	if (IS_ERR(child_inode)) {
	484	iput(parent_inode);
	485	return PTR_ERR(child_inode);
	486	}
	487
	488	ret = inherit_props(trans, child_inode, parent_inode);
	489	iput(child_inode);
	490	iput(parent_inode);
	491
	492	return ret;
	493	}
	494
3dcf96c7	495	void __init btrfs_props_init(void)
63541927	496	{
3dcf96c7	497	int i;
63541927	498
3dcf96c7 AJ	499	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
	500	struct prop_handler *p = &prop_handlers[i];
	501	u64 h = btrfs_name_hash(p->xattr_name, strlen(p->xattr_name));
63541927	502
3dcf96c7	503	hash_add(prop_handlers_ht, &p->node, h);
63541927	504	}
63541927	505	}
e8c9f186	506