diff options
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/free-space-cache.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index 0be7a8742a43..c8090f18c217 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -1356,6 +1356,8 @@ static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl) u64 bytes_per_bg = BITS_PER_BITMAP * ctl->unit; int max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg); + max_bitmaps = max(max_bitmaps, 1); + BUG_ON(ctl->total_bitmaps > max_bitmaps); /* @@ -1636,10 +1638,14 @@ static bool use_bitmap(struct btrfs_free_space_ctl *ctl, } /* - * some block groups are so tiny they can't be enveloped by a bitmap, so - * don't even bother to create a bitmap for this + * The original block groups from mkfs can be really small, like 8 + * megabytes, so don't bother with a bitmap for those entries. However + * some block groups can be smaller than what a bitmap would cover but + * are still large enough that they could overflow the 32k memory limit, + * so allow those block groups to still be allowed to have a bitmap + * entry. */ - if (BITS_PER_BITMAP * ctl->unit > block_group->key.offset) + if (((BITS_PER_BITMAP * ctl->unit) >> 1) > block_group->key.offset) return false; return true; |