From: Greg Kroah-Hartman Date: Mon, 3 Feb 2020 19:49:41 +0000 (+0000) Subject: 4.9-stable patches X-Git-Tag: v5.5.2~11 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1c1267fa2c93966c75fac28715af72b6f50851b3;p=thirdparty%2Fkernel%2Fstable-queue.git 4.9-stable patches added patches: btrfs-do-not-zero-f_bavail-if-we-have-available-space.patch --- diff --git a/queue-4.9/btrfs-do-not-zero-f_bavail-if-we-have-available-space.patch b/queue-4.9/btrfs-do-not-zero-f_bavail-if-we-have-available-space.patch new file mode 100644 index 00000000000..aa28009d10b --- /dev/null +++ b/queue-4.9/btrfs-do-not-zero-f_bavail-if-we-have-available-space.patch @@ -0,0 +1,61 @@ +From d55966c4279bfc6a0cf0b32bf13f5df228a1eeb6 Mon Sep 17 00:00:00 2001 +From: Josef Bacik +Date: Fri, 31 Jan 2020 09:31:05 -0500 +Subject: btrfs: do not zero f_bavail if we have available space + +From: Josef Bacik + +commit d55966c4279bfc6a0cf0b32bf13f5df228a1eeb6 upstream. + +There was some logic added a while ago to clear out f_bavail in statfs() +if we did not have enough free metadata space to satisfy our global +reserve. This was incorrect at the time, however didn't really pose a +problem for normal file systems because we would often allocate chunks +if we got this low on free metadata space, and thus wouldn't really hit +this case unless we were actually full. + +Fast forward to today and now we are much better about not allocating +metadata chunks all of the time. Couple this with d792b0f19711 ("btrfs: +always reserve our entire size for the global reserve") which now means +we'll easily have a larger global reserve than our free space, we are +now more likely to trip over this while still having plenty of space. + +Fix this by skipping this logic if the global rsv's space_info is not +full. space_info->full is 0 unless we've attempted to allocate a chunk +for that space_info and that has failed. If this happens then the space +for the global reserve is definitely sacred and we need to report +b_avail == 0, but before then we can just use our calculated b_avail. + +Reported-by: Martin Steigerwald +Fixes: ca8a51b3a979 ("btrfs: statfs: report zero available if metadata are exhausted") +CC: stable@vger.kernel.org # 4.5+ +Reviewed-by: Qu Wenruo +Tested-By: Martin Steigerwald +Signed-off-by: Josef Bacik +Reviewed-by: David Sterba +Signed-off-by: David Sterba +Signed-off-by: Greg Kroah-Hartman + +--- + fs/btrfs/super.c | 10 +++++++++- + 1 file changed, 9 insertions(+), 1 deletion(-) + +--- a/fs/btrfs/super.c ++++ b/fs/btrfs/super.c +@@ -2164,7 +2164,15 @@ static int btrfs_statfs(struct dentry *d + */ + thresh = 4 * 1024 * 1024; + +- if (!mixed && total_free_meta - thresh < block_rsv->size) ++ /* ++ * We only want to claim there's no available space if we can no longer ++ * allocate chunks for our metadata profile and our global reserve will ++ * not fit in the free metadata space. If we aren't ->full then we ++ * still can allocate chunks and thus are fine using the currently ++ * calculated f_bavail. ++ */ ++ if (!mixed && block_rsv->space_info->full && ++ total_free_meta - thresh < block_rsv->size) + buf->f_bavail = 0; + + buf->f_type = BTRFS_SUPER_MAGIC; diff --git a/queue-4.9/series b/queue-4.9/series index b9f31722832..2cb5445d9ff 100644 --- a/queue-4.9/series +++ b/queue-4.9/series @@ -66,3 +66,4 @@ net-sonic-quiesce-sonic-before-re-initializing-descr.patch seq_tab_next-should-increase-position-index.patch l2t_seq_next-should-increase-position-index.patch net-fix-skb-csum-update-in-inet_proto_csum_replace16.patch +btrfs-do-not-zero-f_bavail-if-we-have-available-space.patch