path: root/fs/btrfs/volumes.h
diff options
authorJeff Mahoney <jeffm@suse.com>2019-03-27 14:24:12 +0200
committerDavid Sterba <dsterba@suse.com>2019-04-29 19:02:37 +0200
commit1c11b63eff2a67906cb9137bc6b2ee27767f313b (patch)
treeb68008df55c8d10a68832dacd19fa0f254b86f09 /fs/btrfs/volumes.h
parentbtrfs: Transpose btrfs_close_devices/btrfs_mapping_tree_free in close_ctree (diff)
btrfs: replace pending/pinned chunks lists with io tree
The pending chunks list contains chunks that are allocated in the current transaction but haven't been created yet. The pinned chunks list contains chunks that are being released in the current transaction. Both describe chunks that are not reflected on disk as in use but are unavailable just the same. The pending chunks list is anchored by the transaction handle, which means that we need to hold a reference to a transaction when working with the list. The way we use them is by iterating over both lists to perform comparisons on the stripes they describe for each device. This is backwards and requires that we keep a transaction handle open while we're trimming. This patchset adds an extent_io_tree to btrfs_device that maintains the allocation state of the device. Extents are set dirty when chunks are first allocated -- when the extent maps are added to the mapping tree. They're cleared when last removed -- when the extent maps are removed from the mapping tree. This matches the lifespan of the pending and pinned chunks list and allows us to do trims on unallocated space safely without pinning the transaction for what may be a lengthy operation. We can also use this io tree to mark which chunks have already been trimmed so we don't repeat the operation. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/volumes.h')
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index d3658a4e65db..6c466ac27c2e 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -133,6 +133,8 @@ struct btrfs_device {
/* Counter to record the change of device stats */
atomic_t dev_stats_ccnt;
atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
+ struct extent_io_tree alloc_state;