From 304d2a9a997d31351355bb9b9389312ec42a4718 Mon Sep 17 00:00:00 2001 From: Zhao Lei Date: Thu, 9 Apr 2015 12:34:43 +0800 Subject: [PATCH] btrfs: wait for delayed iputs on no space 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 Signed-off-by: Chris Mason --- 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 1acd63fcb252b..38b76cc02f486 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3918,6 +3918,9 @@ 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); -- 2.39.5