From 67bc5ad04bea699371a2d52e89690e54963e1397 Mon Sep 17 00:00:00 2001 From: Anand Jain Date: Mon, 31 Jul 2023 19:16:36 +0800 Subject: [PATCH] btrfs: drop redundant check to use fs_devices::metadata_uuid fs_devices::metadata_uuid value is already updated based on the super_block::METADATA_UUID flag for either fsid or metadata_uuid as appropriate. So, fs_devices::metadata_uuid can be used directly. Reviewed-by: Johannes Thumshirn Tested-by: Guilherme G. Piccoli Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 32ec651c570f..0a96ea8c1d3a 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -313,21 +313,16 @@ static bool check_tree_block_fsid(struct extent_buffer *eb) struct btrfs_fs_info *fs_info = eb->fs_info; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs; u8 fsid[BTRFS_FSID_SIZE]; - u8 *metadata_uuid; read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid), BTRFS_FSID_SIZE); + /* - * Checking the incompat flag is only valid for the current fs. For - * seed devices it's forbidden to have their uuid changed so reading - * ->fsid in this case is fine + * alloc_fs_devices() copies the fsid into metadata_uuid if the + * metadata_uuid is unset in the superblock, including for a seed device. + * So, we can use fs_devices->metadata_uuid. */ - if (btrfs_fs_incompat(fs_info, METADATA_UUID)) - metadata_uuid = fs_devices->metadata_uuid; - else - metadata_uuid = fs_devices->fsid; - - if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE)) + if (memcmp(fsid, fs_info->fs_devices->metadata_uuid, BTRFS_FSID_SIZE) == 0) return false; list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) -- 2.39.5