Merge tag 'refactor-rtbitmap-macros-6.7_2023-10-19' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.7-mergeA

xfs: refactor rtbitmap/summary macros [v1.1]

In preparation for adding block headers and enforcing endian order in
rtbitmap and rtsummary blocks, replace open-coded geometry computations
and fugly macros with proper helper functions that can be typechecked.
Soon we'll be needing to add more complex logic to the helpers.

v1.1: various cleanups suggested by hch

With a bit of luck, this should all go splendidly.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>

* tag 'refactor-rtbitmap-macros-6.7_2023-10-19' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux:
  xfs: create helpers for rtbitmap block/wordcount computations
  xfs: convert rt summary macros to helpers
  xfs: convert open-coded xfs_rtword_t pointer accesses to helper
  xfs: remove XFS_BLOCKWSIZE and XFS_BLOCKWMASK macros
  xfs: convert the rtbitmap block and bit macros to static inline functions

7 files changed, 218 insertions, 96 deletions

diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 20acb8573d7a..d48e3a395bd9 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -1142,24 +1142,10 @@ static inline bool xfs_dinode_has_large_extent_counts(
 
 #define	XFS_BLOCKSIZE(mp)	((mp)->m_sb.sb_blocksize)
 #define	XFS_BLOCKMASK(mp)	((mp)->m_blockmask)
-#define	XFS_BLOCKWSIZE(mp)	((mp)->m_blockwsize)
-#define	XFS_BLOCKWMASK(mp)	((mp)->m_blockwmask)
 
 /*
- * RT Summary and bit manipulation macros.
+ * RT bit manipulation macros.
  */
-#define	XFS_SUMOFFS(mp,ls,bb)	((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
-#define	XFS_SUMOFFSTOBLOCK(mp,s)	\
-	(((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
-#define	XFS_SUMPTR(mp,bp,so)	\
-	((xfs_suminfo_t *)((bp)->b_addr + \
-		(((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
-
-#define	XFS_BITTOBLOCK(mp,bi)	((bi) >> (mp)->m_blkbit_log)
-#define	XFS_BLOCKTOBIT(mp,bb)	((bb) << (mp)->m_blkbit_log)
-#define	XFS_BITTOWORD(mp,bi)	\
-	((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
-
 #define	XFS_RTMIN(a,b)	((a) < (b) ? (a) : (b))
 #define	XFS_RTMAX(a,b)	((a) > (b) ? (a) : (b))
 
diff --git a/fs/xfs/libxfs/xfs_rtbitmap.c b/fs/xfs/libxfs/xfs_rtbitmap.c
index 383c6437e042..aefa2b0747a5 100644
--- a/fs/xfs/libxfs/xfs_rtbitmap.c
+++ b/fs/xfs/libxfs/xfs_rtbitmap.c
@@ -103,7 +103,6 @@ xfs_rtfind_back(
 	int		bit;		/* bit number in the word */
 	xfs_fileoff_t	block;		/* bitmap block number */
 	struct xfs_buf	*bp;		/* buf for the block */
-	xfs_rtword_t	*bufp;		/* starting word in buffer */
 	int		error;		/* error value */
 	xfs_rtxnum_t	firstbit;	/* first useful bit in the word */
 	xfs_rtxnum_t	i;		/* current bit number rel. to start */
@@ -111,22 +110,22 @@ xfs_rtfind_back(
 	xfs_rtword_t	mask;		/* mask of relevant bits for value */
 	xfs_rtword_t	want;		/* mask for "good" values */
 	xfs_rtword_t	wdiff;		/* difference from wanted value */
-	int		word;		/* word number in the buffer */
+	unsigned int	word;		/* word number in the buffer */
 
 	/*
 	 * Compute and read in starting bitmap block for starting block.
 	 */
-	block = XFS_BITTOBLOCK(mp, start);
+	block = xfs_rtx_to_rbmblock(mp, start);
 	error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
 	if (error) {
 		return error;
 	}
-	bufp = bp->b_addr;
+
 	/*
 	 * Get the first word's index & point to it.
 	 */
-	word = XFS_BITTOWORD(mp, start);
-	b = &bufp[word];
+	word = xfs_rtx_to_rbmword(mp, start);
+	b = xfs_rbmblock_wordptr(bp, word);
 	bit = (int)(start & (XFS_NBWORD - 1));
 	len = start - limit + 1;
 	/*
@@ -173,9 +172,9 @@ xfs_rtfind_back(
 			if (error) {
 				return error;
 			}
-			bufp = bp->b_addr;
-			word = XFS_BLOCKWMASK(mp);
-			b = &bufp[word];
+
+			word = mp->m_blockwsize - 1;
+			b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the previous word in the buffer.
@@ -219,9 +218,9 @@ xfs_rtfind_back(
 			if (error) {
 				return error;
 			}
-			bufp = bp->b_addr;
-			word = XFS_BLOCKWMASK(mp);
-			b = &bufp[word];
+
+			word = mp->m_blockwsize - 1;
+			b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the previous word in the buffer.
@@ -278,7 +277,6 @@ xfs_rtfind_forw(
 	int		bit;		/* bit number in the word */
 	xfs_fileoff_t	block;		/* bitmap block number */
 	struct xfs_buf	*bp;		/* buf for the block */
-	xfs_rtword_t	*bufp;		/* starting word in buffer */
 	int		error;		/* error value */
 	xfs_rtxnum_t	i;		/* current bit number rel. to start */
 	xfs_rtxnum_t	lastbit;	/* last useful bit in the word */
@@ -286,22 +284,22 @@ xfs_rtfind_forw(
 	xfs_rtword_t	mask;		/* mask of relevant bits for value */
 	xfs_rtword_t	want;		/* mask for "good" values */
 	xfs_rtword_t	wdiff;		/* difference from wanted value */
-	int		word;		/* word number in the buffer */
+	unsigned int	word;		/* word number in the buffer */
 
 	/*
 	 * Compute and read in starting bitmap block for starting block.
 	 */
-	block = XFS_BITTOBLOCK(mp, start);
+	block = xfs_rtx_to_rbmblock(mp, start);
 	error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
 	if (error) {
 		return error;
 	}
-	bufp = bp->b_addr;
+
 	/*
 	 * Get the first word's index & point to it.
 	 */
-	word = XFS_BITTOWORD(mp, start);
-	b = &bufp[word];
+	word = xfs_rtx_to_rbmword(mp, start);
+	b = xfs_rbmblock_wordptr(bp, word);
 	bit = (int)(start & (XFS_NBWORD - 1));
 	len = limit - start + 1;
 	/*
@@ -338,7 +336,7 @@ xfs_rtfind_forw(
 		 * Go on to next block if that's where the next word is
 		 * and we need the next word.
 		 */
-		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+		if (++word == mp->m_blockwsize && i < len) {
 			/*
 			 * If done with this block, get the previous one.
 			 */
@@ -347,8 +345,9 @@ xfs_rtfind_forw(
 			if (error) {
 				return error;
 			}
-			b = bufp = bp->b_addr;
+
 			word = 0;
+			b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the previous word in the buffer.
@@ -383,7 +382,7 @@ xfs_rtfind_forw(
 		 * Go on to next block if that's where the next word is
 		 * and we need the next word.
 		 */
-		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+		if (++word == mp->m_blockwsize && i < len) {
 			/*
 			 * If done with this block, get the next one.
 			 */
@@ -392,8 +391,9 @@ xfs_rtfind_forw(
 			if (error) {
 				return error;
 			}
-			b = bufp = bp->b_addr;
+
 			word = 0;
+			b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the next word in the buffer.
@@ -455,17 +455,18 @@ xfs_rtmodify_summary_int(
 	struct xfs_buf	*bp;		/* buffer for the summary block */
 	int		error;		/* error value */
 	xfs_fileoff_t	sb;		/* summary fsblock */
-	int		so;		/* index into the summary file */
+	xfs_rtsumoff_t	so;		/* index into the summary file */
 	xfs_suminfo_t	*sp;		/* pointer to returned data */
+	unsigned int	infoword;
 
 	/*
 	 * Compute entry number in the summary file.
 	 */
-	so = XFS_SUMOFFS(mp, log, bbno);
+	so = xfs_rtsumoffs(mp, log, bbno);
 	/*
 	 * Compute the block number in the summary file.
 	 */
-	sb = XFS_SUMOFFSTOBLOCK(mp, so);
+	sb = xfs_rtsumoffs_to_block(mp, so);
 	/*
 	 * If we have an old buffer, and the block number matches, use that.
 	 */
@@ -493,7 +494,8 @@ xfs_rtmodify_summary_int(
 	/*
 	 * Point to the summary information, modify/log it, and/or copy it out.
 	 */
-	sp = XFS_SUMPTR(mp, bp, so);
+	infoword = xfs_rtsumoffs_to_infoword(mp, so);
+	sp = xfs_rsumblock_infoptr(bp, infoword);
 	if (delta) {
 		uint first = (uint)((char *)sp - (char *)bp->b_addr);
 
@@ -541,18 +543,17 @@ xfs_rtmodify_range(
 	int		bit;		/* bit number in the word */
 	xfs_fileoff_t	block;		/* bitmap block number */
 	struct xfs_buf	*bp;		/* buf for the block */
-	xfs_rtword_t	*bufp;		/* starting word in buffer */
 	int		error;		/* error value */
 	xfs_rtword_t	*first;		/* first used word in the buffer */
 	int		i;		/* current bit number rel. to start */
 	int		lastbit;	/* last useful bit in word */
 	xfs_rtword_t	mask;		/* mask o frelevant bits for value */
-	int		word;		/* word number in the buffer */
+	unsigned int	word;		/* word number in the buffer */
 
 	/*
 	 * Compute starting bitmap block number.
 	 */
-	block = XFS_BITTOBLOCK(mp, start);
+	block = xfs_rtx_to_rbmblock(mp, start);
 	/*
 	 * Read the bitmap block, and point to its data.
 	 */
@@ -560,12 +561,12 @@ xfs_rtmodify_range(
 	if (error) {
 		return error;
 	}
-	bufp = bp->b_addr;
+
 	/*
 	 * Compute the starting word's address, and starting bit.
 	 */
-	word = XFS_BITTOWORD(mp, start);
-	first = b = &bufp[word];
+	word = xfs_rtx_to_rbmword(mp, start);
+	first = b = xfs_rbmblock_wordptr(bp, word);
 	bit = (int)(start & (XFS_NBWORD - 1));
 	/*
 	 * 0 (allocated) => all zeroes; 1 (free) => all ones.
@@ -593,20 +594,21 @@ xfs_rtmodify_range(
 		 * Go on to the next block if that's where the next word is
 		 * and we need the next word.
 		 */
-		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+		if (++word == mp->m_blockwsize && i < len) {
 			/*
 			 * Log the changed part of this block.
 			 * Get the next one.
 			 */
 			xfs_trans_log_buf(tp, bp,
-				(uint)((char *)first - (char *)bufp),
-				(uint)((char *)b - (char *)bufp));
+				(uint)((char *)first - (char *)bp->b_addr),
+				(uint)((char *)b - (char *)bp->b_addr));
 			error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
 			if (error) {
 				return error;
 			}
-			first = b = bufp = bp->b_addr;
+
 			word = 0;
+			first = b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the next word in the buffer
@@ -633,20 +635,21 @@ xfs_rtmodify_range(
 		 * Go on to the next block if that's where the next word is
 		 * and we need the next word.
 		 */
-		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+		if (++word == mp->m_blockwsize && i < len) {
 			/*
 			 * Log the changed part of this block.
 			 * Get the next one.
 			 */
 			xfs_trans_log_buf(tp, bp,
-				(uint)((char *)first - (char *)bufp),
-				(uint)((char *)b - (char *)bufp));
+				(uint)((char *)first - (char *)bp->b_addr),
+				(uint)((char *)b - (char *)bp->b_addr));
 			error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
 			if (error) {
 				return error;
 			}
-			first = b = bufp = bp->b_addr;
+
 			word = 0;
+			first = b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the next word in the buffer
@@ -676,8 +679,9 @@ xfs_rtmodify_range(
 	 * Log any remaining changed bytes.
 	 */
 	if (b > first)
-		xfs_trans_log_buf(tp, bp, (uint)((char *)first - (char *)bufp),
-			(uint)((char *)b - (char *)bufp - 1));
+		xfs_trans_log_buf(tp, bp,
+			(uint)((char *)first - (char *)bp->b_addr),
+			(uint)((char *)b - (char *)bp->b_addr - 1));
 	return 0;
 }
 
@@ -730,7 +734,7 @@ xfs_rtfree_range(
 	if (preblock < start) {
 		error = xfs_rtmodify_summary(mp, tp,
 			XFS_RTBLOCKLOG(start - preblock),
-			XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
+			xfs_rtx_to_rbmblock(mp, preblock), -1, rbpp, rsb);
 		if (error) {
 			return error;
 		}
@@ -742,7 +746,7 @@ xfs_rtfree_range(
 	if (postblock > end) {
 		error = xfs_rtmodify_summary(mp, tp,
 			XFS_RTBLOCKLOG(postblock - end),
-			XFS_BITTOBLOCK(mp, end + 1), -1, rbpp, rsb);
+			xfs_rtx_to_rbmblock(mp, end + 1), -1, rbpp, rsb);
 		if (error) {
 			return error;
 		}
@@ -753,7 +757,7 @@ xfs_rtfree_range(
 	 */
 	error = xfs_rtmodify_summary(mp, tp,
 		XFS_RTBLOCKLOG(postblock + 1 - preblock),
-		XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
+		xfs_rtx_to_rbmblock(mp, preblock), 1, rbpp, rsb);
 	return error;
 }
 
@@ -775,18 +779,17 @@ xfs_rtcheck_range(
 	int		bit;		/* bit number in the word */
 	xfs_fileoff_t	block;		/* bitmap block number */
 	struct xfs_buf	*bp;		/* buf for the block */
-	xfs_rtword_t	*bufp;		/* starting word in buffer */
 	int		error;		/* error value */
 	xfs_rtxnum_t	i;		/* current bit number rel. to start */
 	xfs_rtxnum_t	lastbit;	/* last useful bit in word */
 	xfs_rtword_t	mask;		/* mask of relevant bits for value */
 	xfs_rtword_t	wdiff;		/* difference from wanted value */
-	int		word;		/* word number in the buffer */
+	unsigned int	word;		/* word number in the buffer */
 
 	/*
 	 * Compute starting bitmap block number
 	 */
-	block = XFS_BITTOBLOCK(mp, start);
+	block = xfs_rtx_to_rbmblock(mp, start);
 	/*
 	 * Read the bitmap block.
 	 */
@@ -794,12 +797,12 @@ xfs_rtcheck_range(
 	if (error) {
 		return error;
 	}
-	bufp = bp->b_addr;
+
 	/*
 	 * Compute the starting word's address, and starting bit.
 	 */
-	word = XFS_BITTOWORD(mp, start);
-	b = &bufp[word];
+	word = xfs_rtx_to_rbmword(mp, start);
+	b = xfs_rbmblock_wordptr(bp, word);
 	bit = (int)(start & (XFS_NBWORD - 1));
 	/*
 	 * 0 (allocated) => all zero's; 1 (free) => all one's.
@@ -836,7 +839,7 @@ xfs_rtcheck_range(
 		 * Go on to next block if that's where the next word is
 		 * and we need the next word.
 		 */
-		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+		if (++word == mp->m_blockwsize && i < len) {
 			/*
 			 * If done with this block, get the next one.
 			 */
@@ -845,8 +848,9 @@ xfs_rtcheck_range(
 			if (error) {
 				return error;
 			}
-			b = bufp = bp->b_addr;
+
 			word = 0;
+			b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the next word in the buffer.
@@ -882,7 +886,7 @@ xfs_rtcheck_range(
 		 * Go on to next block if that's where the next word is
 		 * and we need the next word.
 		 */
-		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+		if (++word == mp->m_blockwsize && i < len) {
 			/*
 			 * If done with this block, get the next one.
 			 */
@@ -891,8 +895,9 @@ xfs_rtcheck_range(
 			if (error) {
 				return error;
 			}
-			b = bufp = bp->b_addr;
+
 			word = 0;
+			b = xfs_rbmblock_wordptr(bp, word);
 		} else {
 			/*
 			 * Go on to the next word in the buffer.
@@ -1130,3 +1135,30 @@ xfs_rtalloc_extent_is_free(
 	*is_free = matches;
 	return 0;
 }
+
+/*
+ * Compute the number of rtbitmap blocks needed to track the given number of rt
+ * extents.
+ */
+xfs_filblks_t
+xfs_rtbitmap_blockcount(
+	struct xfs_mount	*mp,
+	xfs_rtbxlen_t		rtextents)
+{
+	return howmany_64(rtextents, NBBY * mp->m_sb.sb_blocksize);
+}
+
+/*
+ * Compute the number of rtbitmap words needed to populate every block of a
+ * bitmap that is large enough to track the given number of rt extents.
+ */
+unsigned long long
+xfs_rtbitmap_wordcount(
+	struct xfs_mount	*mp,
+	xfs_rtbxlen_t		rtextents)
+{
+	xfs_filblks_t		blocks;
+
+	blocks = xfs_rtbitmap_blockcount(mp, rtextents);
+	return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
+}
diff --git a/fs/xfs/libxfs/xfs_rtbitmap.h b/fs/xfs/libxfs/xfs_rtbitmap.h
index 3686a53e0aed..01eabb9b5516 100644
--- a/fs/xfs/libxfs/xfs_rtbitmap.h
+++ b/fs/xfs/libxfs/xfs_rtbitmap.h
@@ -131,6 +131,94 @@ xfs_rtb_rounddown_rtx(
 	return rounddown_64(rtbno, mp->m_sb.sb_rextsize);
 }
 
+/* Convert an rt extent number to a file block offset in the rt bitmap file. */
+static inline xfs_fileoff_t
+xfs_rtx_to_rbmblock(
+	struct xfs_mount	*mp,
+	xfs_rtxnum_t		rtx)
+{
+	return rtx >> mp->m_blkbit_log;
+}
+
+/* Convert an rt extent number to a word offset within an rt bitmap block. */
+static inline unsigned int
+xfs_rtx_to_rbmword(
+	struct xfs_mount	*mp,
+	xfs_rtxnum_t		rtx)
+{
+	return (rtx >> XFS_NBWORDLOG) & (mp->m_blockwsize - 1);
+}
+
+/* Convert a file block offset in the rt bitmap file to an rt extent number. */
+static inline xfs_rtxnum_t
+xfs_rbmblock_to_rtx(
+	struct xfs_mount	*mp,
+	xfs_fileoff_t		rbmoff)
+{
+	return rbmoff << mp->m_blkbit_log;
+}
+
+/* Return a pointer to a bitmap word within a rt bitmap block. */
+static inline xfs_rtword_t *
+xfs_rbmblock_wordptr(
+	struct xfs_buf		*bp,
+	unsigned int		index)
+{
+	xfs_rtword_t		*words = bp->b_addr;
+
+	return words + index;
+}
+
+/*
+ * Convert a rt extent length and rt bitmap block number to a xfs_suminfo_t
+ * offset within the rt summary file.
+ */
+static inline xfs_rtsumoff_t
+xfs_rtsumoffs(
+	struct xfs_mount	*mp,
+	int			log2_len,
+	xfs_fileoff_t		rbmoff)
+{
+	return log2_len * mp->m_sb.sb_rbmblocks + rbmoff;
+}
+
+/*
+ * Convert an xfs_suminfo_t offset to a file block offset within the rt summary
+ * file.
+ */
+static inline xfs_fileoff_t
+xfs_rtsumoffs_to_block(
+	struct xfs_mount	*mp,
+	xfs_rtsumoff_t		rsumoff)
+{
+	return XFS_B_TO_FSBT(mp, rsumoff * sizeof(xfs_suminfo_t));
+}
+
+/*
+ * Convert an xfs_suminfo_t offset to an info word offset within an rt summary
+ * block.
+ */
+static inline unsigned int
+xfs_rtsumoffs_to_infoword(
+	struct xfs_mount	*mp,
+	xfs_rtsumoff_t		rsumoff)
+{
+	unsigned int		mask = mp->m_blockmask >> XFS_SUMINFOLOG;
+
+	return rsumoff & mask;
+}
+
+/* Return a pointer to a summary info word within a rt summary block. */
+static inline xfs_suminfo_t *
+xfs_rsumblock_infoptr(
+	struct xfs_buf		*bp,
+	unsigned int		index)
+{
+	xfs_suminfo_t		*info = bp->b_addr;
+
+	return info + index;
+}
+
 /*
  * Functions for walking free space rtextents in the realtime bitmap.
  */
@@ -192,6 +280,11 @@ xfs_rtfree_extent(
 /* Same as above, but in units of rt blocks. */
 int xfs_rtfree_blocks(struct xfs_trans *tp, xfs_fsblock_t rtbno,
 		xfs_filblks_t rtlen);
+
+xfs_filblks_t xfs_rtbitmap_blockcount(struct xfs_mount *mp, xfs_rtbxlen_t
+		rtextents);
+unsigned long long xfs_rtbitmap_wordcount(struct xfs_mount *mp,
+		xfs_rtbxlen_t rtextents);
 #else /* CONFIG_XFS_RT */
 # define xfs_rtfree_extent(t,b,l)			(-ENOSYS)
 # define xfs_rtfree_blocks(t,rb,rl)			(-ENOSYS)
@@ -199,6 +292,13 @@ int xfs_rtfree_blocks(struct xfs_trans *tp, xfs_fsblock_t rtbno,
 # define xfs_rtalloc_query_all(m,t,f,p)			(-ENOSYS)
 # define xfs_rtbuf_get(m,t,b,i,p)			(-ENOSYS)
 # define xfs_rtalloc_extent_is_free(m,t,s,l,i)		(-ENOSYS)
+static inline xfs_filblks_t
+xfs_rtbitmap_blockcount(struct xfs_mount *mp, xfs_rtbxlen_t rtextents)
+{
+	/* shut up gcc */
+	return 0;
+}
+# define xfs_rtbitmap_wordcount(mp, r)			(0)
 #endif /* CONFIG_XFS_RT */
 
 #endif /* __XFS_RTBITMAP_H__ */
diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c
index 4629f10d2f67..6cd45e8c118d 100644
--- a/fs/xfs/libxfs/xfs_trans_resv.c
+++ b/fs/xfs/libxfs/xfs_trans_resv.c
@@ -218,11 +218,12 @@ xfs_rtalloc_block_count(
 	struct xfs_mount	*mp,
 	unsigned int		num_ops)
 {
-	unsigned int		blksz = XFS_FSB_TO_B(mp, 1);
-	unsigned int		rtbmp_bytes;
+	unsigned int		rtbmp_blocks;
+	xfs_rtxlen_t		rtxlen;
 
-	rtbmp_bytes = xfs_extlen_to_rtxlen(mp, XFS_MAX_BMBT_EXTLEN) / NBBY;
-	return (howmany(rtbmp_bytes, blksz) + 1) * num_ops;
+	rtxlen = xfs_extlen_to_rtxlen(mp, XFS_MAX_BMBT_EXTLEN);
+	rtbmp_blocks = xfs_rtbitmap_blockcount(mp, rtxlen);
+	return (rtbmp_blocks + 1) * num_ops;
 }
 
 /*
diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h
index c78237852e27..533200c4ccc2 100644
--- a/fs/xfs/libxfs/xfs_types.h
+++ b/fs/xfs/libxfs/xfs_types.h
@@ -19,6 +19,7 @@ typedef int64_t		xfs_fsize_t;	/* bytes in a file */
 typedef uint64_t	xfs_ufsize_t;	/* unsigned bytes in a file */
 
 typedef int32_t		xfs_suminfo_t;	/* type of bitmap summary info */
+typedef uint32_t	xfs_rtsumoff_t;	/* offset of an rtsummary info word */
 typedef uint32_t	xfs_rtword_t;	/* word type for bitmap manipulations */
 
 typedef int64_t		xfs_lsn_t;	/* log sequence number */
@@ -149,6 +150,7 @@ typedef uint32_t	xfs_dqid_t;
  */
 #define	XFS_NBBYLOG	3		/* log2(NBBY) */
 #define	XFS_WORDLOG	2		/* log2(sizeof(xfs_rtword_t)) */
+#define	XFS_SUMINFOLOG	2		/* log2(sizeof(xfs_suminfo_t)) */
 #define	XFS_NBWORDLOG	(XFS_NBBYLOG + XFS_WORDLOG)
 #define	XFS_NBWORD	(1 << XFS_NBWORDLOG)
 #define	XFS_WORDMASK	((1 << XFS_WORDLOG) - 1)
diff --git a/fs/xfs/scrub/rtsummary.c b/fs/xfs/scrub/rtsummary.c
index d363286e8b72..0971d002d906 100644
--- a/fs/xfs/scrub/rtsummary.c
+++ b/fs/xfs/scrub/rtsummary.c
@@ -81,7 +81,7 @@ typedef unsigned int xchk_rtsumoff_t;
 static inline int
 xfsum_load(
 	struct xfs_scrub	*sc,
-	xchk_rtsumoff_t		sumoff,
+	xfs_rtsumoff_t		sumoff,
 	xfs_suminfo_t		*info)
 {
 	return xfile_obj_load(sc->xfile, info, sizeof(xfs_suminfo_t),
@@ -91,7 +91,7 @@ xfsum_load(
 static inline int
 xfsum_store(
 	struct xfs_scrub	*sc,
-	xchk_rtsumoff_t		sumoff,
+	xfs_rtsumoff_t		sumoff,
 	const xfs_suminfo_t	info)
 {
 	return xfile_obj_store(sc->xfile, &info, sizeof(xfs_suminfo_t),
@@ -101,7 +101,7 @@ xfsum_store(
 static inline int
 xfsum_copyout(
 	struct xfs_scrub	*sc,
-	xchk_rtsumoff_t		sumoff,
+	xfs_rtsumoff_t		sumoff,
 	xfs_suminfo_t		*info,
 	unsigned int		nr_words)
 {
@@ -121,7 +121,7 @@ xchk_rtsum_record_free(
 	xfs_fileoff_t			rbmoff;
 	xfs_rtblock_t			rtbno;
 	xfs_filblks_t			rtlen;
-	xchk_rtsumoff_t			offs;
+	xfs_rtsumoff_t			offs;
 	unsigned int			lenlog;
 	xfs_suminfo_t			v = 0;
 	int				error = 0;
@@ -130,9 +130,9 @@ xchk_rtsum_record_free(
 		return error;
 
 	/* Compute the relevant location in the rtsum file. */
-	rbmoff = XFS_BITTOBLOCK(mp, rec->ar_startext);
+	rbmoff = xfs_rtx_to_rbmblock(mp, rec->ar_startext);
 	lenlog = XFS_RTBLOCKLOG(rec->ar_extcount);
-	offs = XFS_SUMOFFS(mp, lenlog, rbmoff);
+	offs = xfs_rtsumoffs(mp, lenlog, rbmoff);
 
 	rtbno = xfs_rtx_to_rtb(mp, rec->ar_startext);
 	rtlen = xfs_rtx_to_rtb(mp, rec->ar_extcount);
@@ -160,12 +160,11 @@ xchk_rtsum_compute(
 	struct xfs_scrub	*sc)
 {
 	struct xfs_mount	*mp = sc->mp;
-	unsigned long long	rtbmp_bytes;
+	unsigned long long	rtbmp_blocks;
 
 	/* If the bitmap size doesn't match the computed size, bail. */
-	rtbmp_bytes = howmany_64(mp->m_sb.sb_rextents, NBBY);
-	if (roundup_64(rtbmp_bytes, mp->m_sb.sb_blocksize) !=
-			mp->m_rbmip->i_disk_size)
+	rtbmp_blocks = xfs_rtbitmap_blockcount(mp, mp->m_sb.sb_rextents);
+	if (XFS_FSB_TO_B(mp, rtbmp_blocks) != mp->m_rbmip->i_disk_size)
 		return -EFSCORRUPTED;
 
 	return xfs_rtalloc_query_all(sc->mp, sc->tp, xchk_rtsum_record_free,
@@ -185,6 +184,7 @@ xchk_rtsum_compare(
 	int			nmap;
 
 	for (off = 0; off < XFS_B_TO_FSB(mp, mp->m_rsumsize); off++) {
+		xfs_suminfo_t	*ondisk_info;
 		int		error = 0;
 
 		if (xchk_should_terminate(sc, &error))
@@ -216,7 +216,8 @@ xchk_rtsum_compare(
 			return error;
 		}
 
-		if (memcmp(bp->b_addr, sc->buf,
+		ondisk_info = xfs_rsumblock_infoptr(bp, 0);
+		if (memcmp(ondisk_info, sc->buf,
 					mp->m_blockwsize << XFS_WORDLOG) != 0)
 			xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, off);
 
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index e5a3200cea72..8e041df12640 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -177,7 +177,7 @@ xfs_rtallocate_range(
 	 */
 	error = xfs_rtmodify_summary(mp, tp,
 		XFS_RTBLOCKLOG(postblock + 1 - preblock),
-		XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
+		xfs_rtx_to_rbmblock(mp, preblock), -1, rbpp, rsb);
 	if (error) {
 		return error;
 	}
@@ -188,7 +188,7 @@ xfs_rtallocate_range(
 	if (preblock < start) {
 		error = xfs_rtmodify_summary(mp, tp,
 			XFS_RTBLOCKLOG(start - preblock),
-			XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
+			xfs_rtx_to_rbmblock(mp, preblock), 1, rbpp, rsb);
 		if (error) {
 			return error;
 		}
@@ -200,7 +200,7 @@ xfs_rtallocate_range(
 	if (postblock > end) {
 		error = xfs_rtmodify_summary(mp, tp,
 			XFS_RTBLOCKLOG(postblock - end),
-			XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
+			xfs_rtx_to_rbmblock(mp, end + 1), 1, rbpp, rsb);
 		if (error) {
 			return error;
 		}
@@ -261,8 +261,8 @@ xfs_rtallocate_extent_block(
 	 * Loop over all the extents starting in this bitmap block,
 	 * looking for one that's long enough.
 	 */
-	for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
-		end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
+	for (i = xfs_rbmblock_to_rtx(mp, bbno), besti = -1, bestlen = 0,
+		end = xfs_rbmblock_to_rtx(mp, bbno + 1) - 1;
 	     i <= end;
 	     i++) {
 		/* Make sure we don't scan off the end of the rt volume. */
@@ -489,7 +489,7 @@ xfs_rtallocate_extent_near(
 		*rtx = r;
 		return 0;
 	}
-	bbno = XFS_BITTOBLOCK(mp, start);
+	bbno = xfs_rtx_to_rbmblock(mp, start);
 	i = 0;
 	ASSERT(minlen != 0);
 	log2len = xfs_highbit32(minlen);
@@ -708,8 +708,8 @@ xfs_rtallocate_extent_size(
 			 * allocator is beyond the next bitmap block,
 			 * skip to that bitmap block.
 			 */
-			if (XFS_BITTOBLOCK(mp, n) > i + 1)
-				i = XFS_BITTOBLOCK(mp, n) - 1;
+			if (xfs_rtx_to_rbmblock(mp, n) > i + 1)
+				i = xfs_rtx_to_rbmblock(mp, n) - 1;
 		}
 	}
 	/*
@@ -771,8 +771,8 @@ xfs_rtallocate_extent_size(
 			 * allocator is beyond the next bitmap block,
 			 * skip to that bitmap block.
 			 */
-			if (XFS_BITTOBLOCK(mp, n) > i + 1)
-				i = XFS_BITTOBLOCK(mp, n) - 1;
+			if (xfs_rtx_to_rbmblock(mp, n) > i + 1)
+				i = xfs_rtx_to_rbmblock(mp, n) - 1;
 		}
 	}
 	/*
@@ -998,7 +998,7 @@ xfs_growfs_rt(
 	 */
 	nrextents = nrblocks;
 	do_div(nrextents, in->extsize);
-	nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
+	nrbmblocks = xfs_rtbitmap_blockcount(mp, nrextents);
 	nrextslog = xfs_highbit32(nrextents);
 	nrsumlevels = nrextslog + 1;
 	nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;