xfs: introduce xfs_aligned_fsb_count
Factor a helper to calculate the extent-size aligned block out of the
iomap code, so that it can be reused by the upcoming reflink dio code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff --git a/fs/xfs/xfs_iomap.h b/fs/xfs/xfs_iomap.h
index 705224b..00db3ec 100644
--- a/fs/xfs/xfs_iomap.h
+++ b/fs/xfs/xfs_iomap.h
@@ -33,6 +33,26 @@ void xfs_bmbt_to_iomap(struct xfs_inode *, struct iomap *,
struct xfs_bmbt_irec *);
xfs_extlen_t xfs_eof_alignment(struct xfs_inode *ip, xfs_extlen_t extsize);
+static inline xfs_filblks_t
+xfs_aligned_fsb_count(
+ xfs_fileoff_t offset_fsb,
+ xfs_filblks_t count_fsb,
+ xfs_extlen_t extsz)
+{
+ if (extsz) {
+ xfs_extlen_t align;
+
+ align = do_mod(offset_fsb, extsz);
+ if (align)
+ count_fsb += align;
+ align = do_mod(count_fsb, extsz);
+ if (align)
+ count_fsb += extsz - align;
+ }
+
+ return count_fsb;
+}
+
extern const struct iomap_ops xfs_iomap_ops;
extern const struct iomap_ops xfs_xattr_iomap_ops;