xfs: provide helper for counting extents from if_bytes

The open-coded pattern:

ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)

is all over the xfs code; provide a new helper
xfs_iext_count(ifp) to count the number of inline extents
in an inode fork.

[dchinner: pick up several missed conversions]

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 23 insertions, 26 deletions

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index c6eb21940783..42f4e7a84e2e 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -515,7 +515,7 @@ xfs_bmap_trace_exlist(
 		state |= BMAP_ATTRFORK;
 
 	ifp = XFS_IFORK_PTR(ip, whichfork);
-	ASSERT(cnt == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
+	ASSERT(cnt == xfs_iext_count(ifp));
 	for (idx = 0; idx < cnt; idx++)
 		trace_xfs_extlist(ip, idx, whichfork, caller_ip);
 }
@@ -811,7 +811,7 @@ try_another_ag:
 				XFS_BTREE_LONG_PTRS);
 
 	arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
-	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
+	nextents =  xfs_iext_count(ifp);
 	for (cnt = i = 0; i < nextents; i++) {
 		ep = xfs_iext_get_ext(ifp, i);
 		if (!isnullstartblock(xfs_bmbt_get_startblock(ep))) {
@@ -1296,7 +1296,7 @@ xfs_bmap_read_extents(
 	/*
 	 * Here with bp and block set to the leftmost leaf node in the tree.
 	 */
-	room = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
+	room = xfs_iext_count(ifp);
 	i = 0;
 	/*
 	 * Loop over all leaf nodes.  Copy information to the extent records.
@@ -1361,7 +1361,7 @@ xfs_bmap_read_extents(
 			return error;
 		block = XFS_BUF_TO_BLOCK(bp);
 	}
-	ASSERT(i == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
+	ASSERT(i == xfs_iext_count(ifp));
 	ASSERT(i == XFS_IFORK_NEXTENTS(ip, whichfork));
 	XFS_BMAP_TRACE_EXLIST(ip, i, whichfork);
 	return 0;
@@ -1404,7 +1404,7 @@ xfs_bmap_search_multi_extents(
 	if (lastx > 0) {
 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx - 1), prevp);
 	}
-	if (lastx < (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))) {
+	if (lastx < xfs_iext_count(ifp)) {
 		xfs_bmbt_get_all(ep, gotp);
 		*eofp = 0;
 	} else {
@@ -1497,7 +1497,7 @@ xfs_bmap_first_unused(
 	    (error = xfs_iread_extents(tp, ip, whichfork)))
 		return error;
 	lowest = *first_unused;
-	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
+	nextents = xfs_iext_count(ifp);
 	for (idx = 0, lastaddr = 0, max = lowest; idx < nextents; idx++) {
 		xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, idx);
 		off = xfs_bmbt_get_startoff(ep);
@@ -1582,7 +1582,7 @@ xfs_bmap_last_extent(
 			return error;
 	}
 
-	nextents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
+	nextents = xfs_iext_count(ifp);
 	if (nextents == 0) {
 		*is_empty = 1;
 		return 0;
@@ -1735,7 +1735,7 @@ xfs_bmap_add_extent_delay_real(
 						&bma->ip->i_d.di_nextents);
 
 	ASSERT(bma->idx >= 0);
-	ASSERT(bma->idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
+	ASSERT(bma->idx <= xfs_iext_count(ifp));
 	ASSERT(!isnullstartblock(new->br_startblock));
 	ASSERT(!bma->cur ||
 	       (bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
@@ -1794,7 +1794,7 @@ xfs_bmap_add_extent_delay_real(
 	 * Don't set contiguous if the combined extent would be too large.
 	 * Also check for all-three-contiguous being too large.
 	 */
-	if (bma->idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
+	if (bma->idx < xfs_iext_count(ifp) - 1) {
 		state |= BMAP_RIGHT_VALID;
 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx + 1), &RIGHT);
 
@@ -2300,7 +2300,7 @@ xfs_bmap_add_extent_unwritten_real(
 	ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
 
 	ASSERT(*idx >= 0);
-	ASSERT(*idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
+	ASSERT(*idx <= xfs_iext_count(ifp));
 	ASSERT(!isnullstartblock(new->br_startblock));
 
 	XFS_STATS_INC(mp, xs_add_exlist);
@@ -2356,7 +2356,7 @@ xfs_bmap_add_extent_unwritten_real(
 	 * Don't set contiguous if the combined extent would be too large.
 	 * Also check for all-three-contiguous being too large.
 	 */
-	if (*idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
+	if (*idx < xfs_iext_count(&ip->i_df) - 1) {
 		state |= BMAP_RIGHT_VALID;
 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx + 1), &RIGHT);
 		if (isnullstartblock(RIGHT.br_startblock))
@@ -2836,7 +2836,7 @@ xfs_bmap_add_extent_hole_delay(
 	 * Check and set flags if the current (right) segment exists.
 	 * If it doesn't exist, we're converting the hole at end-of-file.
 	 */
-	if (*idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
+	if (*idx < xfs_iext_count(ifp)) {
 		state |= BMAP_RIGHT_VALID;
 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx), &right);
 
@@ -2966,7 +2966,7 @@ xfs_bmap_add_extent_hole_real(
 	ifp = XFS_IFORK_PTR(bma->ip, whichfork);
 
 	ASSERT(bma->idx >= 0);
-	ASSERT(bma->idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
+	ASSERT(bma->idx <= xfs_iext_count(ifp));
 	ASSERT(!isnullstartblock(new->br_startblock));
 	ASSERT(!bma->cur ||
 	       !(bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
@@ -2992,7 +2992,7 @@ xfs_bmap_add_extent_hole_real(
 	 * Check and set flags if this segment has a current value.
 	 * Not true if we're inserting into the "hole" at eof.
 	 */
-	if (bma->idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
+	if (bma->idx < xfs_iext_count(ifp)) {
 		state |= BMAP_RIGHT_VALID;
 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx), &right);
 		if (isnullstartblock(right.br_startblock))
@@ -4221,7 +4221,7 @@ xfs_bmapi_read(
 			break;
 
 		/* Else go on to the next record. */
-		if (++lastx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t))
+		if (++lastx < xfs_iext_count(ifp))
 			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx), &got);
 		else
 			eof = 1;
@@ -4733,7 +4733,7 @@ xfs_bmapi_write(
 
 		/* Else go on to the next record. */
 		bma.prev = bma.got;
-		if (++bma.idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t)) {
+		if (++bma.idx < xfs_iext_count(ifp)) {
 			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma.idx),
 					 &bma.got);
 		} else
@@ -4885,7 +4885,7 @@ xfs_bmap_del_extent_delay(
 	da_new = 0;
 
 	ASSERT(*idx >= 0);
-	ASSERT(*idx < ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
+	ASSERT(*idx <= xfs_iext_count(ifp));
 	ASSERT(del->br_blockcount > 0);
 	ASSERT(got->br_startoff <= del->br_startoff);
 	ASSERT(got_endoff >= del_endoff);
@@ -5013,7 +5013,7 @@ xfs_bmap_del_extent_cow(
 	got_endoff = got->br_startoff + got->br_blockcount;
 
 	ASSERT(*idx >= 0);
-	ASSERT(*idx < ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
+	ASSERT(*idx <= xfs_iext_count(ifp));
 	ASSERT(del->br_blockcount > 0);
 	ASSERT(got->br_startoff <= del->br_startoff);
 	ASSERT(got_endoff >= del_endoff);
@@ -5119,8 +5119,7 @@ xfs_bmap_del_extent(
 		state |= BMAP_COWFORK;
 
 	ifp = XFS_IFORK_PTR(ip, whichfork);
-	ASSERT((*idx >= 0) && (*idx < ifp->if_bytes /
-		(uint)sizeof(xfs_bmbt_rec_t)));
+	ASSERT((*idx >= 0) && (*idx < xfs_iext_count(ifp)));
 	ASSERT(del->br_blockcount > 0);
 	ep = xfs_iext_get_ext(ifp, *idx);
 	xfs_bmbt_get_all(ep, &got);
@@ -5445,7 +5444,6 @@ __xfs_bunmapi(
 	int			logflags;	/* transaction logging flags */
 	xfs_extlen_t		mod;		/* rt extent offset */
 	xfs_mount_t		*mp;		/* mount structure */
-	xfs_extnum_t		nextents;	/* number of file extents */
 	xfs_bmbt_irec_t		prev;		/* previous extent record */
 	xfs_fileoff_t		start;		/* first file offset deleted */
 	int			tmp_logflags;	/* partial logging flags */
@@ -5477,8 +5475,7 @@ __xfs_bunmapi(
 	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
 	    (error = xfs_iread_extents(tp, ip, whichfork)))
 		return error;
-	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
-	if (nextents == 0) {
+	if (xfs_iext_count(ifp) == 0) {
 		*rlen = 0;
 		return 0;
 	}
@@ -5963,7 +5960,7 @@ xfs_bmse_shift_one(
 
 	mp = ip->i_mount;
 	ifp = XFS_IFORK_PTR(ip, whichfork);
-	total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
+	total_extents = xfs_iext_count(ifp);
 
 	xfs_bmbt_get_all(gotp, &got);
 
@@ -6140,7 +6137,7 @@ xfs_bmap_shift_extents(
 	 * are collapsing out, so we cannot use the count of real extents here.
 	 * Instead we have to calculate it from the incore fork.
 	 */
-	total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
+	total_extents = xfs_iext_count(ifp);
 	if (total_extents == 0) {
 		*done = 1;
 		goto del_cursor;
@@ -6200,7 +6197,7 @@ xfs_bmap_shift_extents(
 		 * count can change. Update the total and grade the next record.
 		 */
 		if (direction == SHIFT_LEFT) {
-			total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
+			total_extents = xfs_iext_count(ifp);
 			stop_extent = total_extents;
 		}