1 files changed, 43 insertions, 13 deletions

diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
index 52e0f7245afc..55b95d45303b 100644
--- a/fs/xfs/xfs_dquot.c
+++ b/fs/xfs/xfs_dquot.c
@@ -205,16 +205,18 @@ xfs_qm_adjust_dqtimers(
  */
 STATIC void
 xfs_qm_init_dquot_blk(
-	xfs_trans_t	*tp,
-	xfs_mount_t	*mp,
-	xfs_dqid_t	id,
-	uint		type,
-	xfs_buf_t	*bp)
+	struct xfs_trans	*tp,
+	struct xfs_mount	*mp,
+	xfs_dqid_t		id,
+	uint			type,
+	struct xfs_buf		*bp)
 {
 	struct xfs_quotainfo	*q = mp->m_quotainfo;
-	xfs_dqblk_t	*d;
-	xfs_dqid_t	curid;
-	int		i;
+	struct xfs_dqblk	*d;
+	xfs_dqid_t		curid;
+	unsigned int		qflag;
+	unsigned int		blftype;
+	int			i;
 
 	ASSERT(tp);
 	ASSERT(xfs_buf_islocked(bp));
@@ -238,11 +240,39 @@ xfs_qm_init_dquot_blk(
 		}
 	}
 
-	xfs_trans_dquot_buf(tp, bp,
-			    (type & XFS_DQ_USER ? XFS_BLF_UDQUOT_BUF :
-			    ((type & XFS_DQ_PROJ) ? XFS_BLF_PDQUOT_BUF :
-			     XFS_BLF_GDQUOT_BUF)));
-	xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
+	if (type & XFS_DQ_USER) {
+		qflag = XFS_UQUOTA_CHKD;
+		blftype = XFS_BLF_UDQUOT_BUF;
+	} else if (type & XFS_DQ_PROJ) {
+		qflag = XFS_PQUOTA_CHKD;
+		blftype = XFS_BLF_PDQUOT_BUF;
+	} else {
+		qflag = XFS_GQUOTA_CHKD;
+		blftype = XFS_BLF_GDQUOT_BUF;
+	}
+
+	xfs_trans_dquot_buf(tp, bp, blftype);
+
+	/*
+	 * quotacheck uses delayed writes to update all the dquots on disk in an
+	 * efficient manner instead of logging the individual dquot changes as
+	 * they are made. However if we log the buffer allocated here and crash
+	 * after quotacheck while the logged initialisation is still in the
+	 * active region of the log, log recovery can replay the dquot buffer
+	 * initialisation over the top of the checked dquots and corrupt quota
+	 * accounting.
+	 *
+	 * To avoid this problem, quotacheck cannot log the initialised buffer.
+	 * We must still dirty the buffer and write it back before the
+	 * allocation transaction clears the log. Therefore, mark the buffer as
+	 * ordered instead of logging it directly. This is safe for quotacheck
+	 * because it detects and repairs allocated but initialized dquot blocks
+	 * in the quota inodes.
+	 */
+	if (!(mp->m_qflags & qflag))
+		xfs_trans_ordered_buf(tp, bp);
+	else
+		xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
 }
 
 /*