xfs: refactor the ifork block counting function

Refactor the inode fork block counting function to count extents for us
at the same time.  This will be used by the bmbt scrubber function.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 424e3bd..93e9552 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -225,7 +225,8 @@
 STATIC void
 xfs_bmap_count_leaves(
 	struct xfs_ifork	*ifp,
-	int			*count)
+	xfs_extnum_t		*numrecs,
+	xfs_filblks_t		*count)
 {
 	xfs_extnum_t		i;
 	xfs_extnum_t		nr_exts = xfs_iext_count(ifp);
@@ -233,6 +234,7 @@
 	for (i = 0; i < nr_exts; i++) {
 		xfs_bmbt_rec_host_t *frp = xfs_iext_get_ext(ifp, i);
 		if (!isnullstartblock(xfs_bmbt_get_startblock(frp))) {
+			(*numrecs)++;
 			*count += xfs_bmbt_get_blockcount(frp);
 		}
 	}
@@ -247,7 +249,7 @@
 	struct xfs_mount	*mp,
 	struct xfs_btree_block	*block,
 	int			numrecs,
-	int			*count)
+	xfs_filblks_t		*count)
 {
 	int		b;
 	xfs_bmbt_rec_t	*frp;
@@ -262,17 +264,18 @@
  * Recursively walks each level of a btree
  * to count total fsblocks in use.
  */
-STATIC int                                     /* error */
+STATIC int
 xfs_bmap_count_tree(
-	xfs_mount_t     *mp,            /* file system mount point */
-	xfs_trans_t     *tp,            /* transaction pointer */
-	xfs_ifork_t	*ifp,		/* inode fork pointer */
-	xfs_fsblock_t   blockno,	/* file system block number */
-	int             levelin,	/* level in btree */
-	int		*count)		/* Count of blocks */
+	struct xfs_mount	*mp,
+	struct xfs_trans	*tp,
+	struct xfs_ifork	*ifp,
+	xfs_fsblock_t		blockno,
+	int			levelin,
+	xfs_extnum_t		*nextents,
+	xfs_filblks_t		*count)
 {
 	int			error;
-	xfs_buf_t		*bp, *nbp;
+	struct xfs_buf		*bp, *nbp;
 	int			level = levelin;
 	__be64			*pp;
 	xfs_fsblock_t           bno = blockno;
@@ -305,8 +308,9 @@
 		/* Dive to the next level */
 		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
 		bno = be64_to_cpu(*pp);
-		if (unlikely((error =
-		     xfs_bmap_count_tree(mp, tp, ifp, bno, level, count)) < 0)) {
+		error = xfs_bmap_count_tree(mp, tp, ifp, bno, level, nextents,
+				count);
+		if (error) {
 			xfs_trans_brelse(tp, bp);
 			XFS_ERROR_REPORT("xfs_bmap_count_tree(1)",
 					 XFS_ERRLEVEL_LOW, mp);
@@ -318,6 +322,7 @@
 		for (;;) {
 			nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 			numrecs = be16_to_cpu(block->bb_numrecs);
+			(*nextents) += numrecs;
 			xfs_bmap_disk_count_leaves(mp, block, numrecs, count);
 			xfs_trans_brelse(tp, bp);
 			if (nextbno == NULLFSBLOCK)
@@ -339,44 +344,61 @@
  * Count fsblocks of the given fork.  Delayed allocation extents are
  * not counted towards the totals.
  */
-static int					/* error */
+int
 xfs_bmap_count_blocks(
-	xfs_trans_t		*tp,		/* transaction pointer */
-	xfs_inode_t		*ip,		/* incore inode */
-	int			whichfork,	/* data or attr fork */
-	int			*count)		/* out: count of blocks */
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip,
+	int			whichfork,
+	xfs_extnum_t		*nextents,
+	xfs_filblks_t		*count)
 {
-	struct xfs_btree_block	*block;	/* current btree block */
-	xfs_fsblock_t		bno;	/* block # of "block" */
-	xfs_ifork_t		*ifp;	/* fork structure */
-	int			level;	/* btree level, for checking */
-	xfs_mount_t		*mp;	/* file system mount structure */
+	struct xfs_mount	*mp;	/* file system mount structure */
 	__be64			*pp;	/* pointer to block address */
+	struct xfs_btree_block	*block;	/* current btree block */
+	struct xfs_ifork	*ifp;	/* fork structure */
+	xfs_fsblock_t		bno;	/* block # of "block" */
+	int			level;	/* btree level, for checking */
+	int			error;
 
 	bno = NULLFSBLOCK;
 	mp = ip->i_mount;
+	*nextents = 0;
+	*count = 0;
 	ifp = XFS_IFORK_PTR(ip, whichfork);
-	if ( XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ) {
-		xfs_bmap_count_leaves(ifp, count);
+	if (!ifp)
 		return 0;
-	}
 
-	/*
-	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
-	 */
-	block = ifp->if_broot;
-	level = be16_to_cpu(block->bb_level);
-	ASSERT(level > 0);
-	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
-	bno = be64_to_cpu(*pp);
-	ASSERT(bno != NULLFSBLOCK);
-	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
-	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
+	switch (XFS_IFORK_FORMAT(ip, whichfork)) {
+	case XFS_DINODE_FMT_EXTENTS:
+		xfs_bmap_count_leaves(ifp, nextents, count);
+		return 0;
+	case XFS_DINODE_FMT_BTREE:
+		if (!(ifp->if_flags & XFS_IFEXTENTS)) {
+			error = xfs_iread_extents(tp, ip, whichfork);
+			if (error)
+				return error;
+		}
 
-	if (unlikely(xfs_bmap_count_tree(mp, tp, ifp, bno, level, count) < 0)) {
-		XFS_ERROR_REPORT("xfs_bmap_count_blocks(2)", XFS_ERRLEVEL_LOW,
-				 mp);
-		return -EFSCORRUPTED;
+		/*
+		 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
+		 */
+		block = ifp->if_broot;
+		level = be16_to_cpu(block->bb_level);
+		ASSERT(level > 0);
+		pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
+		bno = be64_to_cpu(*pp);
+		ASSERT(bno != NULLFSBLOCK);
+		ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
+		ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
+
+		error = xfs_bmap_count_tree(mp, tp, ifp, bno, level,
+				nextents, count);
+		if (error) {
+			XFS_ERROR_REPORT("xfs_bmap_count_blocks(2)",
+					XFS_ERRLEVEL_LOW, mp);
+			return -EFSCORRUPTED;
+		}
+		return 0;
 	}
 
 	return 0;
@@ -1792,8 +1814,9 @@
 	int			*target_log_flags)
 {
 	struct xfs_ifork	tempifp, *ifp, *tifp;
-	int			aforkblks = 0;
-	int			taforkblks = 0;
+	xfs_filblks_t		aforkblks = 0;
+	xfs_filblks_t		taforkblks = 0;
+	xfs_extnum_t		junk;
 	xfs_extnum_t		nextents;
 	uint64_t		tmp;
 	int			error;
@@ -1803,14 +1826,14 @@
 	 */
 	if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
 	     (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
-		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK,
+		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk,
 				&aforkblks);
 		if (error)
 			return error;
 	}
 	if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
 	     (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
-		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
+		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk,
 				&taforkblks);
 		if (error)
 			return error;
diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
index 135d826..0cede10 100644
--- a/fs/xfs/xfs_bmap_util.h
+++ b/fs/xfs/xfs_bmap_util.h
@@ -70,4 +70,8 @@
 
 xfs_daddr_t xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb);
 
+int xfs_bmap_count_blocks(struct xfs_trans *tp, struct xfs_inode *ip,
+			  int whichfork, xfs_extnum_t *nextents,
+			  xfs_filblks_t *count);
+
 #endif	/* __XFS_BMAP_UTIL_H__ */