From: Zhao Lei <zhao...@cn.fujitsu.com> btrfs will report no_space when we run following write and delete file loop: # FILE_SIZE_M=[ 75% of fs space ] # DEV=[ some dev ] # MNT=[ some dir ] # # mkfs.btrfs -f "$DEV" # mount -o nodatacow "$DEV" "$MNT" # for ((i = 0; i < 100; i++)); do dd if=/dev/zero of="$MNT"/file0 bs=1M count="$FILE_SIZE_M"; rm -f "$MNT"/file0; done #
Reason: iput() and evict() is run after write pages to block device, if write pages work is not finished before next write, the "rm"ed space is not freed, and caused above bug. Fix: We can add "-o flushoncommit" mount option to avoid above bug, but it have performance problem. Actually, we can to wait for on-the-fly writes only when no-space happened, it is which this patch do. Signed-off-by: Zhao Lei <zhao...@cn.fujitsu.com> --- fs/btrfs/extent-tree.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 0572f14..d5ec383 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3725,6 +3725,9 @@ commit_trans: !atomic_read(&root->fs_info->open_ioctl_trans)) { need_commit--; + if (need_commit > 0) + btrfs_wait_ordered_roots(fs_info, -1); + trans = btrfs_join_transaction(root); if (IS_ERR(trans)) return PTR_ERR(trans); -- 1.8.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html