From 42bd8f4fda813558c3045c60ad6436b1c7430ec7 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 [ Upstream commit 9a4e7276d39071576d369e607d7accb84b41d0b4 ] 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 Signed-off-by: Sasha Levin --- 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 3c19380..98a4d52 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3975,6 +3975,9 @@ 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); -- 2.7.4