From: Jeff Mahoney <jeffm@suse.com>
Subject: btrfs: account for pinned bytes in should_alloc_chunk
References: bsc#1040182
Git-commit: f44d2287d2879f50b921e909b2377d6dcba3e251
Patch-mainline: v4.14-rc1

In a heavy write scenario, we can end up with a large number of pinned bytes.
This can translate into (very) premature ENOSPC because pinned bytes
must be accounted for when allowing a reservation but aren't accounted for
when deciding whether to create a new chunk.

This patch adds the accounting to should_alloc_chunk so that we can
create the chunk.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
 fs/btrfs/extent-tree.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4385,7 +4385,7 @@ static int should_alloc_chunk(struct btr
 {
 	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
 	u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
-	u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
+	u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned;
 	u64 thresh;
 
 	if (force == CHUNK_ALLOC_FORCE)