mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-17 01:23:58 -04:00
52b364fed6
Adapt tmpfs/shmem to use the rhashtable-based xattr path and switch from an embedded struct to pointer-based lazy allocation. Change shmem_inode_info.xattrs from embedded 'struct simple_xattrs' to a pointer 'struct simple_xattrs *', initialized to NULL. This avoids the rhashtable overhead for every tmpfs inode, which helps when a lot of inodes exist. The xattr store is allocated on first use: - shmem_initxattrs(): Allocates via simple_xattrs_alloc() when security modules set initial xattrs during inode creation. - shmem_xattr_handler_set(): Allocates on first setxattr, with a short-circuit for removal when no xattrs are stored yet. All read paths (shmem_xattr_handler_get, shmem_listxattr) check for NULL xattrs pointer and return -ENODATA or 0 respectively. Replaced xattr entries are freed via simple_xattr_free_rcu() to allow concurrent RCU readers to finish. shmem_evict_inode() conditionally frees the xattr store only when allocated. Also change simple_xattr_add() from void to int to propagate rhashtable insertion failures. shmem_initxattrs() is the only caller. Link: https://patch.msgid.link/20260216-work-xattr-socket-v1-3-c2efa4f74cb7@kernel.org Acked-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>