From 146d1448846b318e0fabc05e19f3b8f88629a22d Mon Sep 17 00:00:00 2001
From: Goldwyn Rodrigues <rgoldwyn@suse.com>
Date: Mon, 27 Mar 2017 12:29:57 -0500
Subject: [PATCH 3/3] btrfs: qgroups: Retry after commit on getting EDQUOT
Patch-mainline: Submitted, https://patchwork.kernel.org/patch/9647211/
References: bsc#1019614
We are facing the same problem with EDQUOT which was experienced with
ENOSPC. Not sure if we require a full ticketing system such as ENOSPC, but
here is a quick fix, which may be too big a hammer.
Quotas are reserved during the start of an operation, incrementing
qg->reserved. However, it is written to disk in a commit_transaction
which could take as long as commit_interval. In the meantime there
could be deletions which are not accounted for because deletions are
accounted for only while committed (free_refroot). So, when we get
a EDQUOT flush the data to disk and try again.
This fixes fstests btrfs/139.
Here is a sample script which shows this issue.
DEVICE=/dev/vdb
MOUNTPOINT=/mnt
TESTVOL=$MOUNTPOINT/tmp
QUOTA=5
PROG=btrfs
DD_BS="4k"
DD_COUNT="256"
RUN_TIMES=5000
mkfs.btrfs -f $DEVICE
mount -o commit=240 $DEVICE $MOUNTPOINT
$PROG subvolume create $TESTVOL
$PROG quota enable $TESTVOL
$PROG qgroup limit ${QUOTA}G $TESTVOL
typeset -i DD_RUN_GOOD
typeset -i QUOTA
function _check_cmd() {
if [[ ${?} > 0 ]]; then
echo -n "$(date) E: Running previous command"
echo ${*}
echo "Without sync"
$PROG qgroup show -pcreFf ${TESTVOL}
echo "With sync"
$PROG qgroup show -pcreFf --sync ${TESTVOL}
exit 1
fi
}
while true; do
DD_RUN_GOOD=$RUN_TIMES
while (( ${DD_RUN_GOOD} != 0 )); do
dd if=/dev/zero of=${TESTVOL}/quotatest${DD_RUN_GOOD} bs=${DD_BS} count=${DD_COUNT}
_check_cmd "dd if=/dev/zero of=${TESTVOL}/quotatest${DD_RUN_GOOD} bs=${DD_BS} count=${DD_COUNT}"
DD_RUN_GOOD=(${DD_RUN_GOOD}-1)
done
$PROG qgroup show -pcref $TESTVOL
echo "----------- Cleanup ---------- "
rm $TESTVOL/quotatest*
done
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/qgroup.c | 24 +++++++++++++++++++++++-
1 file changed, 23 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 82b3df3..8d5c738 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2340,6 +2340,7 @@ static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce)
struct btrfs_fs_info *fs_info = root->fs_info;
u64 ref_root = root->root_key.objectid;
int ret = 0;
+ int retried = 0;
struct ulist_node *unode;
struct ulist_iterator uiter;
@@ -2348,7 +2349,7 @@ static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce)
if (num_bytes == 0)
return 0;
-
+retry:
spin_lock(&fs_info->qgroup_lock);
quota_root = fs_info->quota_root;
if (!quota_root)
@@ -2375,6 +2376,27 @@ static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce)
qg = u64_to_ptr(unode->aux);
if (enforce && !qgroup_check_limits(qg, num_bytes)) {
+ /*
+ * Commit the tree and retry, since we may have
+ * deletions which would free up space.
+ */
+ if (!retried && qg->reserved > 0) {
+ struct btrfs_trans_handle *trans;
+
+ spin_unlock(&fs_info->qgroup_lock);
+ ret = btrfs_start_delalloc_inodes(root, 0);
+ if (ret)
+ return ret;
+ btrfs_wait_ordered_extents(root, -1, 0, (u64)-1);
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+ ret = btrfs_commit_transaction(trans, root);
+ if (ret)
+ return ret;
+ retried++;
+ goto retry;
+ }
ret = -EDQUOT;
goto out;
}
--
2.10.2