xfs: specify AG in bulk req

Add a new xfs_bulk_ireq flag to constrain the iteration to a single AG.
If the passed-in startino value is zero then we start with the first
inode in the AG that the user passes in; otherwise, we iterate only
within the same AG as the passed-in inode.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h
index aa4918a..d7b3b71 100644
--- a/fs/xfs/libxfs/xfs_fs.h
+++ b/fs/xfs/libxfs/xfs_fs.h
@@ -462,11 +462,17 @@ struct xfs_bulk_ireq {
 	uint32_t	flags;		/* I/O: operation flags		*/
 	uint32_t	icount;		/* I: count of entries in buffer */
 	uint32_t	ocount;		/* O: count of entries filled out */
-	uint32_t	reserved32;	/* must be zero			*/
+	uint32_t	agno;		/* I: see comment for IREQ_AGNO	*/
 	uint64_t	reserved[5];	/* must be zero			*/
 };
 
-#define XFS_BULK_IREQ_FLAGS_ALL	(0)
+/*
+ * Only return results from the specified @agno.  If @ino is zero, start
+ * with the first inode of @agno.
+ */
+#define XFS_BULK_IREQ_AGNO	(1 << 0)
+
+#define XFS_BULK_IREQ_FLAGS_ALL	(XFS_BULK_IREQ_AGNO)
 
 /*
  * ioctl structures for v5 bulkstat and inumbers requests
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index ae7b743..e1e1d9d 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -844,7 +844,6 @@ xfs_bulk_ireq_setup(
 {
 	if (hdr->icount == 0 ||
 	    (hdr->flags & ~XFS_BULK_IREQ_FLAGS_ALL) ||
-	    hdr->reserved32 ||
 	    memchr_inv(hdr->reserved, 0, sizeof(hdr->reserved)))
 		return -EINVAL;
 
@@ -852,6 +851,29 @@ xfs_bulk_ireq_setup(
 	breq->ubuffer = ubuffer;
 	breq->icount = hdr->icount;
 	breq->ocount = 0;
+	breq->flags = 0;
+
+	/*
+	 * The IREQ_AGNO flag means that we only want results from a given AG.
+	 * If @hdr->ino is zero, we start iterating in that AG.  If @hdr->ino is
+	 * beyond the specified AG then we return no results.
+	 */
+	if (hdr->flags & XFS_BULK_IREQ_AGNO) {
+		if (hdr->agno >= mp->m_sb.sb_agcount)
+			return -EINVAL;
+
+		if (breq->startino == 0)
+			breq->startino = XFS_AGINO_TO_INO(mp, hdr->agno, 0);
+		else if (XFS_INO_TO_AGNO(mp, breq->startino) < hdr->agno)
+			return -EINVAL;
+
+		breq->flags |= XFS_IBULK_SAME_AG;
+
+		/* Asking for an inode past the end of the AG?  We're done! */
+		if (XFS_INO_TO_AGNO(mp, breq->startino) > hdr->agno)
+			return XFS_ITER_ABORT;
+	} else if (hdr->agno)
+		return -EINVAL;
 
 	/* Asking for an inode past the end of the FS?  We're done! */
 	if (XFS_INO_TO_AGNO(mp, breq->startino) >= mp->m_sb.sb_agcount)
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index 687c873..cda8ae9 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -247,8 +247,8 @@ xfs_bulkstat(
 	if (!bc.buf)
 		return -ENOMEM;
 
-	error = xfs_iwalk(breq->mp, NULL, breq->startino, xfs_bulkstat_iwalk,
-			breq->icount, &bc);
+	error = xfs_iwalk(breq->mp, NULL, breq->startino, breq->flags,
+			xfs_bulkstat_iwalk, breq->icount, &bc);
 
 	kmem_free(bc.buf);
 
@@ -367,7 +367,7 @@ xfs_inumbers(
 	if (xfs_bulkstat_already_done(breq->mp, breq->startino))
 		return 0;
 
-	error = xfs_inobt_walk(breq->mp, NULL, breq->startino,
+	error = xfs_inobt_walk(breq->mp, NULL, breq->startino, breq->flags,
 			xfs_inumbers_walk, breq->icount, &ic);
 
 	/*
diff --git a/fs/xfs/xfs_itable.h b/fs/xfs/xfs_itable.h
index fa9fb91..e90c1fc 100644
--- a/fs/xfs/xfs_itable.h
+++ b/fs/xfs/xfs_itable.h
@@ -12,8 +12,12 @@ struct xfs_ibulk {
 	xfs_ino_t		startino; /* start with this inode */
 	unsigned int		icount;   /* number of elements in ubuffer */
 	unsigned int		ocount;   /* number of records returned */
+	unsigned int		flags;    /* see XFS_IBULK_FLAG_* */
 };
 
+/* Only iterate within the same AG as startino */
+#define XFS_IBULK_SAME_AG	(XFS_IWALK_SAME_AG)
+
 /* Return value that means we want to abort the walk. */
 #define XFS_IBULK_ABORT		(XFS_IWALK_ABORT)
 
diff --git a/fs/xfs/xfs_iwalk.c b/fs/xfs/xfs_iwalk.c
index d3008c2..8c7d7271 100644
--- a/fs/xfs/xfs_iwalk.c
+++ b/fs/xfs/xfs_iwalk.c
@@ -519,6 +519,7 @@ xfs_iwalk(
 	struct xfs_mount	*mp,
 	struct xfs_trans	*tp,
 	xfs_ino_t		startino,
+	unsigned int		flags,
 	xfs_iwalk_fn		iwalk_fn,
 	unsigned int		inode_records,
 	void			*data)
@@ -538,6 +539,7 @@ xfs_iwalk(
 	int			error;
 
 	ASSERT(agno < mp->m_sb.sb_agcount);
+	ASSERT(!(flags & ~XFS_IWALK_FLAGS_ALL));
 
 	error = xfs_iwalk_alloc(&iwag);
 	if (error)
@@ -548,6 +550,8 @@ xfs_iwalk(
 		if (error)
 			break;
 		iwag.startino = XFS_AGINO_TO_INO(mp, agno + 1, 0);
+		if (flags & XFS_INOBT_WALK_SAME_AG)
+			break;
 	}
 
 	xfs_iwalk_free(&iwag);
@@ -586,6 +590,7 @@ int
 xfs_iwalk_threaded(
 	struct xfs_mount	*mp,
 	xfs_ino_t		startino,
+	unsigned int		flags,
 	xfs_iwalk_fn		iwalk_fn,
 	unsigned int		inode_records,
 	bool			polled,
@@ -597,6 +602,7 @@ xfs_iwalk_threaded(
 	int			error;
 
 	ASSERT(agno < mp->m_sb.sb_agcount);
+	ASSERT(!(flags & ~XFS_IWALK_FLAGS_ALL));
 
 	nr_threads = xfs_pwork_guess_datadev_parallelism(mp);
 	error = xfs_pwork_init(mp, &pctl, xfs_iwalk_ag_work, "xfs_iwalk",
@@ -618,6 +624,8 @@ xfs_iwalk_threaded(
 		iwag->sz_recs = xfs_iwalk_prefetch(inode_records);
 		xfs_pwork_queue(&pctl, &iwag->pwork);
 		startino = XFS_AGINO_TO_INO(mp, agno + 1, 0);
+		if (flags & XFS_INOBT_WALK_SAME_AG)
+			break;
 	}
 
 	if (polled)
@@ -674,6 +682,7 @@ xfs_inobt_walk(
 	struct xfs_mount	*mp,
 	struct xfs_trans	*tp,
 	xfs_ino_t		startino,
+	unsigned int		flags,
 	xfs_inobt_walk_fn	inobt_walk_fn,
 	unsigned int		inobt_records,
 	void			*data)
@@ -691,6 +700,7 @@ xfs_inobt_walk(
 	int			error;
 
 	ASSERT(agno < mp->m_sb.sb_agcount);
+	ASSERT(!(flags & ~XFS_INOBT_WALK_FLAGS_ALL));
 
 	error = xfs_iwalk_alloc(&iwag);
 	if (error)
@@ -701,6 +711,8 @@ xfs_inobt_walk(
 		if (error)
 			break;
 		iwag.startino = XFS_AGINO_TO_INO(mp, agno + 1, 0);
+		if (flags & XFS_INOBT_WALK_SAME_AG)
+			break;
 	}
 
 	xfs_iwalk_free(&iwag);
diff --git a/fs/xfs/xfs_iwalk.h b/fs/xfs/xfs_iwalk.h
index 6746286..6c960e1 100644
--- a/fs/xfs/xfs_iwalk.h
+++ b/fs/xfs/xfs_iwalk.h
@@ -14,10 +14,16 @@ typedef int (*xfs_iwalk_fn)(struct xfs_mount *mp, struct xfs_trans *tp,
 #define XFS_IWALK_ABORT		(XFS_ITER_ABORT)
 
 int xfs_iwalk(struct xfs_mount *mp, struct xfs_trans *tp, xfs_ino_t startino,
-		xfs_iwalk_fn iwalk_fn, unsigned int inode_records, void *data);
+		unsigned int flags, xfs_iwalk_fn iwalk_fn,
+		unsigned int inode_records, void *data);
 int xfs_iwalk_threaded(struct xfs_mount *mp, xfs_ino_t startino,
-		xfs_iwalk_fn iwalk_fn, unsigned int inode_records, bool poll,
-		void *data);
+		unsigned int flags, xfs_iwalk_fn iwalk_fn,
+		unsigned int inode_records, bool poll, void *data);
+
+/* Only iterate inodes within the same AG as @startino. */
+#define XFS_IWALK_SAME_AG	(0x1)
+
+#define XFS_IWALK_FLAGS_ALL	(XFS_IWALK_SAME_AG)
 
 /* Walk all inode btree records in the filesystem starting from @startino. */
 typedef int (*xfs_inobt_walk_fn)(struct xfs_mount *mp, struct xfs_trans *tp,
@@ -28,7 +34,13 @@ typedef int (*xfs_inobt_walk_fn)(struct xfs_mount *mp, struct xfs_trans *tp,
 #define XFS_INOBT_WALK_ABORT	(XFS_IWALK_ABORT)
 
 int xfs_inobt_walk(struct xfs_mount *mp, struct xfs_trans *tp,
-		xfs_ino_t startino, xfs_inobt_walk_fn inobt_walk_fn,
-		unsigned int inobt_records, void *data);
+		xfs_ino_t startino, unsigned int flags,
+		xfs_inobt_walk_fn inobt_walk_fn, unsigned int inobt_records,
+		void *data);
+
+/* Only iterate inobt records within the same AG as @startino. */
+#define XFS_INOBT_WALK_SAME_AG	(XFS_IWALK_SAME_AG)
+
+#define XFS_INOBT_WALK_FLAGS_ALL (XFS_INOBT_WALK_SAME_AG)
 
 #endif /* __XFS_IWALK_H__ */
diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index 2a59c2a..5e7a37f 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -1300,7 +1300,8 @@ xfs_qm_quotacheck(
 		flags |= XFS_PQUOTA_CHKD;
 	}
 
-	error = xfs_iwalk_threaded(mp, 0, xfs_qm_dqusage_adjust, 0, true, NULL);
+	error = xfs_iwalk_threaded(mp, 0, 0, xfs_qm_dqusage_adjust, 0, true,
+			NULL);
 	if (error)
 		goto error_return;