From: Josef Bacik <josef@toxicpanda.com>
Date: Tue, 21 Jul 2020 10:22:14 -0400
Subject: btrfs: handle U64_MAX for shrink_delalloc
Git-commit: d7f81fac97e6d06c4e9bf090085137aa2dddff99
Patch-mainline: v5.10-rc1
References: bsc#1135481
Data allocations are going to want to pass in U64_MAX for flushing
space, adjust shrink_delalloc to handle this properly.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Acked-by: Nikolay Borisov <nborisov@suse.com>
---
fs/btrfs/space-info.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -409,8 +409,19 @@ static void shrink_delalloc(struct btrfs
enum btrfs_reserve_flush_enum flush;
/* Calc the number of the pages we need flush for space reservation */
- items = calc_reclaim_items_nr(fs_info, to_reclaim);
- to_reclaim = items * EXTENT_SIZE_PER_ITEM;
+ if (to_reclaim == U64_MAX) {
+ items = U64_MAX;
+ } else {
+ /*
+ * to_reclaim is set to however much metadata we need to
+ * reclaim, but reclaiming that much data doesn't really track
+ * exactly, so increase the amount to reclaim by 2x in order to
+ * make sure we're flushing enough delalloc to hopefully reclaim
+ * some metadata reservations.
+ */
+ items = calc_reclaim_items_nr(fs_info, to_reclaim) * 2;
+ to_reclaim = items * EXTENT_SIZE_PER_ITEM;
+ }
trans = (struct btrfs_trans_handle *)current->journal_info;
space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
@@ -607,7 +618,7 @@ static int flush_space(struct btrfs_fs_i
break;
case FLUSH_DELALLOC:
case FLUSH_DELALLOC_WAIT:
- shrink_delalloc(fs_info, num_bytes * 2,
+ shrink_delalloc(fs_info, num_bytes,
state == FLUSH_DELALLOC_WAIT);
break;
case FLUSH_DELAYED_REFS_NR: