@@ -164,10 +164,10 @@ static int can_overcommit(struct btrfs_fs_info *fs_info,
enum btrfs_reserve_flush_enum flush,
bool system_chunk)
{
+ enum btrfs_raid_types index;
u64 profile;
u64 avail;
u64 used;
- int factor;
/* Don't overcommit when in mixed mode. */
if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
@@ -179,16 +179,15 @@ static int can_overcommit(struct btrfs_fs_info *fs_info,
profile = btrfs_metadata_alloc_profile(fs_info);
used = btrfs_space_info_used(space_info, true);
- avail = atomic64_read(&fs_info->free_chunk_space);
/*
- * If we have dup, raid1 or raid10 then only half of the free
- * space is actually usable. For raid56, the space info used
- * doesn't include the parity drive, so we don't have to
- * change the math
+ * Grab avail space from per-profile array which should be as accurate
+ * as chunk allocator.
*/
- factor = btrfs_bg_type_to_factor(profile);
- avail = div_u64(avail, factor);
+ index = btrfs_bg_flags_to_raid_index(profile);
+ spin_lock(&fs_info->fs_devices->per_profile_lock);
+ avail = fs_info->fs_devices->per_profile_avail[index];
+ spin_unlock(&fs_info->fs_devices->per_profile_lock);
/*
* If we aren't flushing all things, let us overcommit up to
For the following disk layout, can_overcommit() can cause false confidence in available space: devid 1 unallocated: 1T devid 2 unallocated: 10T metadata type: RAID1 As can_overcommit() simply uses unallocated space with factor to calculate the allocatable metadata chunk size. can_overcommit() believes we still have 5.5T for metadata chunks, while the truth is, we only have 1T available for metadata chunks. This can lead to ENOSPC at run_delalloc_range() and cause transaction abort. Since factor based calculation can't distinguish RAID1/RAID10 and DUP at all, we need proper chunk-allocator level awareness to do such estimation. Thankfully, we have per-profile available space already calculated, just use that facility to avoid such false confidence. Reported-by: Marc Lehmann <schmorp@schmorp.de> Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/space-info.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-)