From 760e69c4c2e2f475a812bdd414b62758215ce9cb Mon Sep 17 00:00:00 2001
From: Naohiro Aota <naohiro.aota@wdc.com>
Date: Tue, 22 Mar 2022 18:11:34 +0900
Subject: btrfs: zoned: activate block group only for extent allocation
In btrfs_make_block_group(), we activate the allocated block group,
expecting that the block group is soon used for allocation. However, the
chunk allocation from flush_space() context broke the assumption. There
can be a large time gap between the chunk allocation time and the extent
allocation time from the chunk.
Activating the empty block groups pre-allocated from flush_space()
context can exhaust the active zone counter of a device. Once we use all
the active zone counts for empty pre-allocated block groups, we cannot
activate new block group for the other things: metadata, tree-log, or
data relocation block group. That failure results in a fake -ENOSPC.
This patch introduces CHUNK_ALLOC_FORCE_FOR_EXTENT to distinguish the
chunk allocation from find_free_extent(). Now, the new block group is
activated only in that context.
Fixes: eb66a010d518 ("btrfs: zoned: activate new block group")
CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/block-group.h | 4 ++++
1 file changed, 4 insertions(+)
(limited to 'fs/btrfs/block-group.h')
diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index 93aabc68bb6a..e8308f2ad07d 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -35,11 +35,15 @@ enum btrfs_discard_state {
* the FS with empty chunks
*
* CHUNK_ALLOC_FORCE means it must try to allocate one
+ *
+ * CHUNK_ALLOC_FORCE_FOR_EXTENT like CHUNK_ALLOC_FORCE but called from
+ * find_free_extent() that also activaes the zone
*/
enum btrfs_chunk_alloc_enum {
CHUNK_ALLOC_NO_FORCE,
CHUNK_ALLOC_LIMITED,
CHUNK_ALLOC_FORCE,
+ CHUNK_ALLOC_FORCE_FOR_EXTENT,
};
struct btrfs_caching_control {
--
cgit