xfs: stop using q_core.d_flags in the quota code

Use the incore dq_flags to figure out the dquot type.  This is the first
step towards removing xfs_disk_dquot from the incore dquot.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>

fs/xfs/xfs_dquot.c

@@ -561,6 +561,15 @@ xfs_dquot_from_disk(
 	return 0;
 }
 
+/* Copy the in-core quota fields into the on-disk buffer. */
+void
+xfs_dquot_to_disk(
+	struct xfs_disk_dquot	*ddqp,
+	struct xfs_dquot	*dqp)
+{
+	memcpy(ddqp, &dqp->q_core, sizeof(struct xfs_disk_dquot));
+}
+
 /* Allocate and initialize the dquot buffer for this in-core dquot. */
 static int
 xfs_qm_dqread_alloc(
@@ -1115,6 +1124,21 @@ xfs_dquot_done(
 	}
 }
 
+/* Check incore dquot for errors before we flush. */
+static xfs_failaddr_t
+xfs_qm_dqflush_check(
+	struct xfs_dquot	*dqp)
+{
+	__u8			type = dqp->dq_flags & XFS_DQ_ALLTYPES;
+
+	if (type != XFS_DQ_USER &&
+	    type != XFS_DQ_GROUP &&
+	    type != XFS_DQ_PROJ)
+		return __this_address;
+
+	return NULL;
+}
+
 /*
  * Write a modified dquot to disk.
  * The dquot must be locked and the flush lock too taken by caller.
@@ -1173,8 +1197,16 @@ xfs_qm_dqflush(
 		goto out_abort;
 	}
 
-	/* This is the only portion of data that needs to persist */
-	memcpy(ddqp, &dqp->q_core, sizeof(struct xfs_disk_dquot));
+	fa = xfs_qm_dqflush_check(dqp);
+	if (fa) {
+		xfs_alert(mp, "corrupt dquot ID 0x%x in memory at %pS",
+				be32_to_cpu(dqp->q_core.d_id), fa);
+		xfs_buf_relse(bp);
+		error = -EFSCORRUPTED;
+		goto out_abort;
+	}
+
+	xfs_dquot_to_disk(ddqp, dqp);
 
 	/*
 	 * Clear the dirty field and remember the flush lsn for later use.

fs/xfs/xfs_dquot.h

@@ -145,6 +145,8 @@ static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
 	return false;
 }
 
+void xfs_dquot_to_disk(struct xfs_disk_dquot *ddqp, struct xfs_dquot *dqp);
+
 #define XFS_DQ_IS_LOCKED(dqp)	(mutex_is_locked(&((dqp)->q_qlock)))
 #define XFS_DQ_IS_DIRTY(dqp)	((dqp)->q_flags & XFS_DQFLAG_DIRTY)
 #define XFS_QM_ISUDQ(dqp)	((dqp)->dq_flags & XFS_DQ_USER)

fs/xfs/xfs_dquot_item.c

@@ -45,6 +45,7 @@ xfs_qm_dquot_logitem_format(
 	struct xfs_log_item	*lip,
 	struct xfs_log_vec	*lv)
 {
+	struct xfs_disk_dquot	ddq;
 	struct xfs_dq_logitem	*qlip = DQUOT_ITEM(lip);
 	struct xfs_log_iovec	*vecp = NULL;
 	struct xfs_dq_logformat	*qlf;
@@ -58,8 +59,9 @@ xfs_qm_dquot_logitem_format(
 	qlf->qlf_boffset = qlip->qli_dquot->q_bufoffset;
 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_dq_logformat));
 
-	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT,
-			&qlip->qli_dquot->q_core,
+	xfs_dquot_to_disk(&ddq, qlip->qli_dquot);
+
+	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT, &ddq,
 			sizeof(struct xfs_disk_dquot));
 }