xfs: create a helper to convert extlen to rtextlen

Create a helper to compute the realtime extent (xfs_rtxlen_t) from an
extent length (xfs_extlen_t) value.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/libxfs/xfs_rtbitmap.h

@@ -31,6 +31,14 @@ xfs_extlen_to_rtxmod(
 	return len % mp->m_sb.sb_rextsize;
 }
 
+static inline xfs_rtxlen_t
+xfs_extlen_to_rtxlen(
+	struct xfs_mount	*mp,
+	xfs_extlen_t		len)
+{
+	return len / mp->m_sb.sb_rextsize;
+}
+
 /*
  * Functions for walking free space rtextents in the realtime bitmap.
  */

fs/xfs/libxfs/xfs_trans_resv.c

@@ -19,6 +19,7 @@
 #include "xfs_trans.h"
 #include "xfs_qm.h"
 #include "xfs_trans_space.h"
+#include "xfs_rtbitmap.h"
 
 #define _ALLOC	true
 #define _FREE	false
@@ -220,7 +221,7 @@ xfs_rtalloc_block_count(
 	unsigned int		blksz = XFS_FSB_TO_B(mp, 1);
 	unsigned int		rtbmp_bytes;
 
-	rtbmp_bytes = (XFS_MAX_BMBT_EXTLEN / mp->m_sb.sb_rextsize) / NBBY;
+	rtbmp_bytes = xfs_extlen_to_rtxlen(mp, XFS_MAX_BMBT_EXTLEN) / NBBY;
 	return (howmany(rtbmp_bytes, blksz) + 1) * num_ops;
 }
 

fs/xfs/xfs_bmap_util.c

@@ -90,7 +90,7 @@ xfs_bmap_rtalloc(
 
 	align = xfs_get_extsz_hint(ap->ip);
 retry:
-	prod = align / mp->m_sb.sb_rextsize;
+	prod = xfs_extlen_to_rtxlen(mp, align);
 	error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
 					align, 1, ap->eof, 0,
 					ap->conv, &ap->offset, &ap->length);
@@ -117,17 +117,14 @@ xfs_bmap_rtalloc(
 		prod = 1;
 	/*
 	 * Set ralen to be the actual requested length in rtextents.
-	 */
-	ralen = ap->length / mp->m_sb.sb_rextsize;
-	/*
+	 *
 	 * If the old value was close enough to XFS_BMBT_MAX_EXTLEN that
 	 * we rounded up to it, cut it back so it's valid again.
 	 * Note that if it's a really large request (bigger than
 	 * XFS_BMBT_MAX_EXTLEN), we don't hear about that number, and can't
 	 * adjust the starting point to match it.
 	 */
-	if (xfs_rtxlen_to_extlen(mp, ralen) >= XFS_MAX_BMBT_EXTLEN)
-		ralen = XFS_MAX_BMBT_EXTLEN / mp->m_sb.sb_rextsize;
+	ralen = xfs_extlen_to_rtxlen(mp, min(ap->length, XFS_MAX_BMBT_EXTLEN));
 
 	/*
 	 * Lock out modifications to both the RT bitmap and summary inodes
@@ -164,7 +161,7 @@ xfs_bmap_rtalloc(
 		do_div(ap->blkno, mp->m_sb.sb_rextsize);
 	rtx = ap->blkno;
 	ap->length = ralen;
-	raminlen = max_t(xfs_extlen_t, 1, minlen / mp->m_sb.sb_rextsize);
+	raminlen = max_t(xfs_rtxlen_t, 1, xfs_extlen_to_rtxlen(mp, minlen));
 	error = xfs_rtallocate_extent(ap->tp, ap->blkno, raminlen, ap->length,
 			&ralen, ap->wasdel, prod, &rtx);
 	if (error)

fs/xfs/xfs_trans.c

@@ -24,6 +24,7 @@
 #include "xfs_dquot_item.h"
 #include "xfs_dquot.h"
 #include "xfs_icache.h"
+#include "xfs_rtbitmap.h"
 
 struct kmem_cache	*xfs_trans_cache;
 
@@ -1196,7 +1197,7 @@ xfs_trans_alloc_inode(
 
 retry:
 	error = xfs_trans_alloc(mp, resv, dblocks,
-			rblocks / mp->m_sb.sb_rextsize,
+			xfs_extlen_to_rtxlen(mp, rblocks),
 			force ? XFS_TRANS_RESERVE : 0, &tp);
 	if (error)
 		return error;