From: Josef Bacik <josef@toxicpanda.com>
Date: Fri, 13 Mar 2020 15:58:06 -0400
Subject: btrfs: allow us to use up to 90% of the global rsv for unlink
Patch-mainline: Submitted, https://lore.kernel.org/linux-btrfs/20200313195809.141753-1-josef@toxicpanda.com/
References: bsc#1165949

We previously had a limit of stealing 50% of the global reserve for
unlink.  This was from a time when the global reserve was used for the
delayed refs as well.  However now those reservations are kept separate,
so the global reserve can be depleted much more to allow us to make
progress for space restoring operations like unlink.  Change the minimum
amount of space required to be left in the global reserve to 10%.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Acked-by: Nikolay Borisov <nborisov@suse.com>
---
 fs/btrfs/space-info.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 21482914dd13..177cb4054443 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -859,7 +859,7 @@ static bool steal_from_global_rsv(struct btrfs_fs_info *fs_info,
 		return false;

 	spin_lock(&global_rsv->lock);
-	min_bytes = div_factor(global_rsv->size, 5);
+	min_bytes = div_factor(global_rsv->size, 1);
 	if (global_rsv->reserved < min_bytes + ticket->bytes) {
 		spin_unlock(&global_rsv->lock);
 		return false;