xfs: move the quotaoff dqrele inode walk into xfs_icache.c

The only external caller of xfs_inode_walk* happens in quotaoff, when we
want to walk all the incore inodes to detach the dquots.  Move this code
to xfs_icache.c so that we can hide xfs_inode_walk as the starting step
in more cleanups of inode walks.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

fs/xfs/xfs_icache.c

@@ -26,6 +26,18 @@
 
 #include <linux/iversion.h>
 
+/*
+ * Private inode cache walk flags for struct xfs_eofblocks.  Must not coincide
+ * with XFS_EOF_FLAGS_*.
+ */
+#define XFS_ICWALK_FLAG_DROP_UDQUOT	(1U << 31)
+#define XFS_ICWALK_FLAG_DROP_GDQUOT	(1U << 30)
+#define XFS_ICWALK_FLAG_DROP_PDQUOT	(1U << 29)
+
+#define XFS_ICWALK_PRIVATE_FLAGS	(XFS_ICWALK_FLAG_DROP_UDQUOT | \
+					 XFS_ICWALK_FLAG_DROP_GDQUOT | \
+					 XFS_ICWALK_FLAG_DROP_PDQUOT)
+
 /*
  * Allocate and initialise an xfs_inode.
  */
@@ -890,7 +902,7 @@ xfs_inode_walk_get_perag(
  * Call the @execute function on all incore inodes matching the radix tree
  * @tag.
  */
-int
+static int
 xfs_inode_walk(
 	struct xfs_mount	*mp,
 	int			iter_flags,
@@ -915,8 +927,59 @@ xfs_inode_walk(
 		}
 	}
 	return last_error;
+	BUILD_BUG_ON(XFS_ICWALK_PRIVATE_FLAGS & XFS_EOF_FLAGS_VALID);
 }
 
+#ifdef CONFIG_XFS_QUOTA
+/* Drop this inode's dquots. */
+static int
+xfs_dqrele_inode(
+	struct xfs_inode	*ip,
+	void			*priv)
+{
+	struct xfs_eofblocks	*eofb = priv;
+
+	xfs_ilock(ip, XFS_ILOCK_EXCL);
+	if (eofb->eof_flags & XFS_ICWALK_FLAG_DROP_UDQUOT) {
+		xfs_qm_dqrele(ip->i_udquot);
+		ip->i_udquot = NULL;
+	}
+	if (eofb->eof_flags & XFS_ICWALK_FLAG_DROP_GDQUOT) {
+		xfs_qm_dqrele(ip->i_gdquot);
+		ip->i_gdquot = NULL;
+	}
+	if (eofb->eof_flags & XFS_ICWALK_FLAG_DROP_PDQUOT) {
+		xfs_qm_dqrele(ip->i_pdquot);
+		ip->i_pdquot = NULL;
+	}
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	return 0;
+}
+
+/*
+ * Detach all dquots from incore inodes if we can.  The caller must already
+ * have dropped the relevant XFS_[UGP]QUOTA_ACTIVE flags so that dquots will
+ * not get reattached.
+ */
+int
+xfs_dqrele_all_inodes(
+	struct xfs_mount	*mp,
+	unsigned int		qflags)
+{
+	struct xfs_eofblocks	eofb = { .eof_flags = 0 };
+
+	if (qflags & XFS_UQUOTA_ACCT)
+		eofb.eof_flags |= XFS_ICWALK_FLAG_DROP_UDQUOT;
+	if (qflags & XFS_GQUOTA_ACCT)
+		eofb.eof_flags |= XFS_ICWALK_FLAG_DROP_GDQUOT;
+	if (qflags & XFS_PQUOTA_ACCT)
+		eofb.eof_flags |= XFS_ICWALK_FLAG_DROP_PDQUOT;
+
+	return xfs_inode_walk(mp, XFS_INODE_WALK_INEW_WAIT, xfs_dqrele_inode,
+			&eofb, XFS_ICI_NO_TAG);
+}
+#endif /* CONFIG_XFS_QUOTA */
+
 /*
  * Grab the inode for reclaim exclusively.
  *

fs/xfs/xfs_icache.h

@@ -68,9 +68,11 @@ void xfs_inode_clear_cowblocks_tag(struct xfs_inode *ip);
 
 void xfs_blockgc_worker(struct work_struct *work);
 
-int xfs_inode_walk(struct xfs_mount *mp, int iter_flags,
+#ifdef CONFIG_XFS_QUOTA
-	int (*execute)(struct xfs_inode *ip, void *args),
+int xfs_dqrele_all_inodes(struct xfs_mount *mp, unsigned int qflags);
-	void *args, int tag);
+#else
+# define xfs_dqrele_all_inodes(mp, qflags)	(0)
+#endif
 
 int xfs_icache_inode_is_allocated(struct xfs_mount *mp, struct xfs_trans *tp,
 				  xfs_ino_t ino, bool *inuse);

fs/xfs/xfs_qm.h

@@ -142,7 +142,6 @@ extern void		xfs_qm_destroy_quotainfo(struct xfs_mount *);
 
 /* dquot stuff */
 extern void		xfs_qm_dqpurge_all(struct xfs_mount *, uint);
-extern void		xfs_qm_dqrele_all_inodes(struct xfs_mount *, uint);
 
 /* quota ops */
 extern int		xfs_qm_scall_trunc_qfiles(struct xfs_mount *, uint);

fs/xfs/xfs_qm_syscalls.c

@@ -201,7 +201,8 @@ xfs_qm_scall_quotaoff(
 	 * depend on the quota inodes (and other things) being valid as long as
 	 * we keep the lock(s).
 	 */
-	xfs_qm_dqrele_all_inodes(mp, flags);
+	error = xfs_dqrele_all_inodes(mp, flags);
+	ASSERT(!error);
 
 	/*
 	 * Next we make the changes in the quota flag in the mount struct.
@@ -747,54 +748,3 @@ xfs_qm_scall_getquota_next(
 	xfs_qm_dqput(dqp);
 	return error;
 }
-
-STATIC int
-xfs_dqrele_inode(
-	struct xfs_inode	*ip,
-	void			*args)
-{
-	uint			*flags = args;
-
-	/* skip quota inodes */
-	if (ip == ip->i_mount->m_quotainfo->qi_uquotaip ||
-	    ip == ip->i_mount->m_quotainfo->qi_gquotaip ||
-	    ip == ip->i_mount->m_quotainfo->qi_pquotaip) {
-		ASSERT(ip->i_udquot == NULL);
-		ASSERT(ip->i_gdquot == NULL);
-		ASSERT(ip->i_pdquot == NULL);
-		return 0;
-	}
-
-	xfs_ilock(ip, XFS_ILOCK_EXCL);
-	if ((*flags & XFS_UQUOTA_ACCT) && ip->i_udquot) {
-		xfs_qm_dqrele(ip->i_udquot);
-		ip->i_udquot = NULL;
-	}
-	if ((*flags & XFS_GQUOTA_ACCT) && ip->i_gdquot) {
-		xfs_qm_dqrele(ip->i_gdquot);
-		ip->i_gdquot = NULL;
-	}
-	if ((*flags & XFS_PQUOTA_ACCT) && ip->i_pdquot) {
-		xfs_qm_dqrele(ip->i_pdquot);
-		ip->i_pdquot = NULL;
-	}
-	xfs_iunlock(ip, XFS_ILOCK_EXCL);
-	return 0;
-}
-
-
-/*
- * Go thru all the inodes in the file system, releasing their dquots.
- *
- * Note that the mount structure gets modified to indicate that quotas are off
- * AFTER this, in the case of quotaoff.
- */
-void
-xfs_qm_dqrele_all_inodes(
-	struct xfs_mount	*mp,
-	uint			flags)
-{
-	ASSERT(mp->m_quotainfo);
-	xfs_inode_walk(mp, XFS_INODE_WALK_INEW_WAIT, xfs_dqrele_inode,
-			&flags, XFS_ICI_NO_TAG);
-}