[XFS] Add xfs_map_buffer helper, use it in a couple of places.
SGI-PV: 950211
SGI-Modid: xfs-linux-melb:xfs-kern:25312a
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nathan Scott <nathans@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 58fc7ad..4b6bfdb 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -487,28 +487,37 @@
}
STATIC void
+xfs_map_buffer(
+ struct buffer_head *bh,
+ xfs_iomap_t *mp,
+ xfs_off_t offset,
+ uint block_bits)
+{
+ sector_t bn;
+
+ ASSERT(mp->iomap_bn != IOMAP_DADDR_NULL);
+
+ bn = (mp->iomap_bn >> (block_bits - BBSHIFT)) +
+ ((offset - mp->iomap_offset) >> block_bits);
+
+ ASSERT(bn || (mp->iomap_flags & IOMAP_REALTIME));
+
+ bh->b_blocknr = bn;
+ set_buffer_mapped(bh);
+}
+
+STATIC void
xfs_map_at_offset(
struct buffer_head *bh,
loff_t offset,
int block_bits,
xfs_iomap_t *iomapp)
{
- xfs_daddr_t bn;
- int sector_shift;
-
ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE));
ASSERT(!(iomapp->iomap_flags & IOMAP_DELAY));
- ASSERT(iomapp->iomap_bn != IOMAP_DADDR_NULL);
-
- sector_shift = block_bits - BBSHIFT;
- bn = (iomapp->iomap_bn >> sector_shift) +
- ((offset - iomapp->iomap_offset) >> block_bits);
-
- ASSERT(bn || (iomapp->iomap_flags & IOMAP_REALTIME));
- ASSERT((bn << sector_shift) >= iomapp->iomap_bn);
lock_buffer(bh);
- bh->b_blocknr = bn;
+ xfs_map_buffer(bh, iomapp, offset, block_bits);
bh->b_bdev = iomapp->iomap_target->bt_bdev;
set_buffer_mapped(bh);
clear_buffer_delay(bh);
@@ -1246,21 +1255,13 @@
return 0;
if (iomap.iomap_bn != IOMAP_DADDR_NULL) {
- xfs_daddr_t bn;
- xfs_off_t delta;
-
- /* For unwritten extents do not report a disk address on
+ /*
+ * For unwritten extents do not report a disk address on
* the read case (treat as if we're reading into a hole).
*/
if (create || !(iomap.iomap_flags & IOMAP_UNWRITTEN)) {
- delta = offset - iomap.iomap_offset;
- delta >>= inode->i_blkbits;
-
- bn = iomap.iomap_bn >> (inode->i_blkbits - BBSHIFT);
- bn += delta;
- BUG_ON(!bn && !(iomap.iomap_flags & IOMAP_REALTIME));
- bh_result->b_blocknr = bn;
- set_buffer_mapped(bh_result);
+ xfs_map_buffer(bh_result, &iomap, offset,
+ inode->i_blkbits);
}
if (create && (iomap.iomap_flags & IOMAP_UNWRITTEN)) {
if (direct)