From a3c54b0be1a218bdd8e42abf9ecfd9bddf1eadee Mon Sep 17 00:00:00 2001 From: Anand Jain Date: Wed, 24 May 2023 20:02:41 +0800 Subject: [PATCH] btrfs: simplify how changed fsid and metadata_uuid is checked We often check if the metadata_uuid is not the same as fsid, and then we check if the given fsid matches the metadata_uuid. This patch refactors this logic into function match_fsid_changed and utilize it. Signed-off-by: Anand Jain Signed-off-by: David Sterba --- fs/btrfs/volumes.c | 47 ++++++++++++++++++++++++++--------------------- 1 file changed, 26 insertions(+), 21 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 1affe63..a4bfec0 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -457,6 +457,19 @@ static noinline struct btrfs_fs_devices *find_fsid( return NULL; } +/* + * First check if the metadata_uuid is different from the fsid in the given + * fs_devices. Then check if the given fsid is the same as the metadata_uuid + * in the fs_devices. If it is, return true; otherwise, return false. + */ +static inline bool check_fsid_changed(const struct btrfs_fs_devices *fs_devices, + const u8 *fsid) +{ + return memcmp(fs_devices->fsid, fs_devices->metadata_uuid, + BTRFS_FSID_SIZE) != 0 && + memcmp(fs_devices->metadata_uuid, fsid, BTRFS_FSID_SIZE) == 0; +} + static struct btrfs_fs_devices *find_fsid_with_metadata_uuid( struct btrfs_super_block *disk_super) { @@ -485,13 +498,11 @@ static struct btrfs_fs_devices *find_fsid_with_metadata_uuid( * CHANGING_FSID_V2 flag set. */ list_for_each_entry(fs_devices, &fs_uuids, fs_list) { - if (fs_devices->fsid_change && - memcmp(fs_devices->metadata_uuid, - fs_devices->fsid, BTRFS_FSID_SIZE) != 0 && - memcmp(disk_super->metadata_uuid, fs_devices->metadata_uuid, - BTRFS_FSID_SIZE) == 0) { + if (!fs_devices->fsid_change) + continue; + + if (check_fsid_changed(fs_devices, disk_super->metadata_uuid)) return fs_devices; - } } return find_fsid(disk_super->fsid, disk_super->metadata_uuid); @@ -682,18 +693,16 @@ static struct btrfs_fs_devices *find_fsid_inprogress( struct btrfs_fs_devices *fs_devices; list_for_each_entry(fs_devices, &fs_uuids, fs_list) { - if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, - BTRFS_FSID_SIZE) != 0 && - memcmp(fs_devices->metadata_uuid, disk_super->fsid, - BTRFS_FSID_SIZE) == 0 && !fs_devices->fsid_change) { + if (fs_devices->fsid_change) + continue; + + if (check_fsid_changed(fs_devices, disk_super->fsid)) return fs_devices; - } } return find_fsid(disk_super->fsid, NULL); } - static struct btrfs_fs_devices *find_fsid_changed( struct btrfs_super_block *disk_super) { @@ -710,10 +719,7 @@ static struct btrfs_fs_devices *find_fsid_changed( */ list_for_each_entry(fs_devices, &fs_uuids, fs_list) { /* Changed UUIDs */ - if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, - BTRFS_FSID_SIZE) != 0 && - memcmp(fs_devices->metadata_uuid, disk_super->metadata_uuid, - BTRFS_FSID_SIZE) == 0 && + if (check_fsid_changed(fs_devices, disk_super->metadata_uuid) && memcmp(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE) != 0) return fs_devices; @@ -744,11 +750,10 @@ static struct btrfs_fs_devices *find_fsid_reverted_metadata( * fs_devices equal to the FSID of the disk. */ list_for_each_entry(fs_devices, &fs_uuids, fs_list) { - if (memcmp(fs_devices->fsid, fs_devices->metadata_uuid, - BTRFS_FSID_SIZE) != 0 && - memcmp(fs_devices->metadata_uuid, disk_super->fsid, - BTRFS_FSID_SIZE) == 0 && - fs_devices->fsid_change) + if (!fs_devices->fsid_change) + continue; + + if (check_fsid_changed(fs_devices, disk_super->fsid)) return fs_devices; } -- 2.7.4