diff options
| author | Stefan Behrens <sbehrens@giantdisaster.de> | 2013-08-15 17:11:21 +0200 |
|---|---|---|
| committer | Chris Mason <chris.mason@fusionio.com> | 2013-09-01 08:15:56 -0400 |
| commit | 803b2f54fb4faf6d76fca43e59bcc555d9713cd4 (patch) | |
| tree | f5e5c56d186aa1829aaedb652756ec8f4644e05b /fs/btrfs/disk-io.c | |
| parent | dd5f9615fc5c5e8d3751aab3a17b92768fb1ce70 (diff) | |
Btrfs: fill UUID tree initially
When the UUID tree is initially created, a task is spawned that
walks through the root tree. For each found subvolume root_item,
the uuid and received_uuid entries in the UUID tree are added.
This is such a quick operation so that in case somebody wants
to unmount the filesystem while the task is still running, the
unmount is delayed until the UUID tree building task is finished.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Diffstat (limited to 'fs/btrfs/disk-io.c')
| -rw-r--r-- | fs/btrfs/disk-io.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 80bd63738c6..fa49e900216 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -31,6 +31,7 @@ #include <linux/migrate.h> #include <linux/ratelimit.h> #include <linux/uuid.h> +#include <linux/semaphore.h> #include <asm/unaligned.h> #include "compat.h" #include "ctree.h" @@ -2297,6 +2298,7 @@ int open_ctree(struct super_block *sb, init_rwsem(&fs_info->extent_commit_sem); init_rwsem(&fs_info->cleanup_work_sem); init_rwsem(&fs_info->subvol_sem); + sema_init(&fs_info->uuid_tree_rescan_sem, 1); fs_info->dev_replace.lock_owner = 0; atomic_set(&fs_info->dev_replace.nesting_level, 0); mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount); @@ -3554,6 +3556,11 @@ int close_ctree(struct btrfs_root *root) fs_info->closing = 1; smp_mb(); + /* wait for the uuid_scan task to finish */ + down(&fs_info->uuid_tree_rescan_sem); + /* avoid complains from lockdep et al., set sem back to initial state */ + up(&fs_info->uuid_tree_rescan_sem); + /* pause restriper - we want to resume on mount */ btrfs_pause_balance(fs_info); |