Commit 0e852ab8 authored by Chung-Chiang Cheng's avatar Chung-Chiang Cheng Committed by David Sterba
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btrfs: do not allow compression on nodatacow files 



Compression and nodatacow are mutually exclusive. A similar issue was
fixed by commit f37c563b ("btrfs: add missing check for nocow and
compression inode flags"). Besides ioctl, there is another way to
enable/disable/reset compression directly via xattr. The following
steps will result in a invalid combination.

  $ touch bar
  $ chattr +C bar
  $ lsattr bar
  ---------------C-- bar
  $ setfattr -n btrfs.compression -v zstd bar
  $ lsattr bar
  --------c------C-- bar

To align with the logic in check_fsflags, nocompress will also be
unacceptable after this patch, to prevent mix any compression-related
options with nodatacow.

  $ touch bar
  $ chattr +C bar
  $ lsattr bar
  ---------------C-- bar
  $ setfattr -n btrfs.compression -v zstd bar
  setfattr: bar: Invalid argument
  $ setfattr -n btrfs.compression -v no bar
  setfattr: bar: Invalid argument

When both compression and nodatacow are enabled, then
btrfs_run_delalloc_range prefers nodatacow and no compression happens.

Reported-by: default avatarJayce Lin <jaycelin@synology.com>
CC: stable@vger.kernel.org # 5.10.x: e6f9d696: btrfs: export a helper for compression hard check
CC: stable@vger.kernel.org # 5.10.x
Reviewed-by: default avatarFilipe Manana <fdmanana@suse.com>
Signed-off-by: default avatarChung-Chiang Cheng <cccheng@synology.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent e6f9d696

fs/btrfs/props.c

+11 −5
Original line number Diff line number Diff line
@@ -17,7 +17,8 @@ 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 char *value, size_t len);

	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);

	int inheritable;
@@ -55,7 +56,8 @@ find_prop_handler(const char *name, 
	return NULL;

}



int btrfs_validate_prop(const char *name, const char *value, size_t value_len)

int btrfs_validate_prop(const struct btrfs_inode *inode, const char *name,

			const char *value, size_t value_len)

{

	const struct prop_handler *handler;
@@ -69,7 +71,7 @@ int btrfs_validate_prop(const char *name, const char *value, size_t value_len) 
	if (value_len == 0)

		return 0;



	return handler->validate(value, value_len);

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

}



int btrfs_set_prop(struct btrfs_trans_handle *trans, struct inode *inode,
@@ -252,8 +254,12 @@ int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path) 
	return ret;

}



static int prop_compression_validate(const char *value, size_t len)

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;
@@ -364,7 +370,7 @@ static int inherit_props(struct btrfs_trans_handle *trans, 
		 * 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(value, strlen(value));

		ret = h->validate(BTRFS_I(inode), value, strlen(value));

		if (ret)

			continue;

fs/btrfs/props.h

+2 −1
Original line number Diff line number Diff line
@@ -13,7 +13,8 @@ void __init btrfs_props_init(void); 
int btrfs_set_prop(struct btrfs_trans_handle *trans, struct inode *inode,

		   const char *name, const char *value, size_t value_len,

		   int flags);

int btrfs_validate_prop(const char *name, const char *value, size_t value_len);

int btrfs_validate_prop(const struct btrfs_inode *inode, const char *name,

			const char *value, size_t value_len);



int btrfs_load_inode_props(struct inode *inode, struct btrfs_path *path);

fs/btrfs/xattr.c

+1 −1
Original line number Diff line number Diff line
@@ -403,7 +403,7 @@ static int btrfs_xattr_handler_set_prop(const struct xattr_handler *handler, 
	struct btrfs_root *root = BTRFS_I(inode)->root;



	name = xattr_full_name(handler, name);

	ret = btrfs_validate_prop(name, value, size);

	ret = btrfs_validate_prop(BTRFS_I(inode), name, value, size);

	if (ret)

		return ret;