Merge tag 'refactor-rtbitmap-accessors-6.7_2023-10-19' of...

Merge tag 'refactor-rtbitmap-accessors-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 accessors [v1.2]

Since the rtbitmap and rtsummary accessor functions have proven more
controversial than the rest of the macro refactoring, split the patchset
into two to make review easier.

v1.1: various cleanups suggested by hch
v1.2: rework the accessor functions to reduce the amount of cursor
      tracking required, and create explicit bitmap/summary logging
      functions

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-accessors-6.7_2023-10-19' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux:
  xfs: use accessor functions for summary info words
  xfs: create helpers for rtsummary block/wordcount computations
  xfs: use accessor functions for bitmap words
  xfs: create a helper to handle logging parts of rt bitmap/summary blocks

fs/xfs/libxfs/xfs_format.h

@@ -690,6 +690,22 @@ struct xfs_agfl {
 	    ASSERT(xfs_daddr_to_agno(mp, d) == \
 		   xfs_daddr_to_agno(mp, (d) + (len) - 1)))
 
+/*
+ * Realtime bitmap information is accessed by the word, which is currently
+ * stored in host-endian format.
+ */
+union xfs_rtword_raw {
+	__u32		old;
+};
+
+/*
+ * Realtime summary counts are accessed by the word, which is currently
+ * stored in host-endian format.
+ */
+union xfs_suminfo_raw {
+	__u32		old;
+};
+
 /*
  * XFS Timestamps
  * ==============

fs/xfs/libxfs/xfs_rtbitmap.h

@@ -159,16 +159,39 @@ xfs_rbmblock_to_rtx(
 }
 
 /* Return a pointer to a bitmap word within a rt bitmap block. */
-static inline xfs_rtword_t *
+static inline union xfs_rtword_raw *
 xfs_rbmblock_wordptr(
 	struct xfs_buf		*bp,
 	unsigned int		index)
 {
-	xfs_rtword_t		*words = bp->b_addr;
+	union xfs_rtword_raw	*words = bp->b_addr;
 
 	return words + index;
 }
 
+/* Convert an ondisk bitmap word to its incore representation. */
+static inline xfs_rtword_t
+xfs_rtbitmap_getword(
+	struct xfs_buf		*bp,
+	unsigned int		index)
+{
+	union xfs_rtword_raw	*word = xfs_rbmblock_wordptr(bp, index);
+
+	return word->old;
+}
+
+/* Set an ondisk bitmap word from an incore representation. */
+static inline void
+xfs_rtbitmap_setword(
+	struct xfs_buf		*bp,
+	unsigned int		index,
+	xfs_rtword_t		value)
+{
+	union xfs_rtword_raw	*word = xfs_rbmblock_wordptr(bp, index);
+
+	word->old = value;
+}
+
 /*
  * Convert a rt extent length and rt bitmap block number to a xfs_suminfo_t
  * offset within the rt summary file.
@@ -209,16 +232,40 @@ xfs_rtsumoffs_to_infoword(
 }
 
 /* Return a pointer to a summary info word within a rt summary block. */
-static inline xfs_suminfo_t *
+static inline union xfs_suminfo_raw *
 xfs_rsumblock_infoptr(
 	struct xfs_buf		*bp,
 	unsigned int		index)
 {
-	xfs_suminfo_t		*info = bp->b_addr;
+	union xfs_suminfo_raw	*info = bp->b_addr;
 
 	return info + index;
 }
 
+/* Get the current value of a summary counter. */
+static inline xfs_suminfo_t
+xfs_suminfo_get(
+	struct xfs_buf		*bp,
+	unsigned int		index)
+{
+	union xfs_suminfo_raw	*info = xfs_rsumblock_infoptr(bp, index);
+
+	return info->old;
+}
+
+/* Add to the current value of a summary counter and return the new value. */
+static inline xfs_suminfo_t
+xfs_suminfo_add(
+	struct xfs_buf		*bp,
+	unsigned int		index,
+	int			delta)
+{
+	union xfs_suminfo_raw	*info = xfs_rsumblock_infoptr(bp, index);
+
+	info->old += delta;
+	return info->old;
+}
+
 /*
  * Functions for walking free space rtextents in the realtime bitmap.
  */
@@ -285,6 +332,11 @@ 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);
+
+xfs_filblks_t xfs_rtsummary_blockcount(struct xfs_mount *mp,
+		unsigned int rsumlevels, xfs_extlen_t rbmblocks);
+unsigned long long xfs_rtsummary_wordcount(struct xfs_mount *mp,
+		unsigned int rsumlevels, xfs_extlen_t rbmblocks);
 #else /* CONFIG_XFS_RT */
 # define xfs_rtfree_extent(t,b,l)			(-ENOSYS)
 # define xfs_rtfree_blocks(t,rb,rl)			(-ENOSYS)
@@ -299,6 +351,8 @@ xfs_rtbitmap_blockcount(struct xfs_mount *mp, xfs_rtbxlen_t rtextents)
 	return 0;
 }
 # define xfs_rtbitmap_wordcount(mp, r)			(0)
+# define xfs_rtsummary_blockcount(mp, l, b)		(0)
+# define xfs_rtsummary_wordcount(mp, l, b)		(0)
 #endif /* CONFIG_XFS_RT */
 
 #endif /* __XFS_RTBITMAP_H__ */

fs/xfs/scrub/rtsummary.c

@@ -82,9 +82,10 @@ static inline int
 xfsum_load(
 	struct xfs_scrub	*sc,
 	xfs_rtsumoff_t		sumoff,
-	xfs_suminfo_t		*info)
+	union xfs_suminfo_raw	*rawinfo)
 {
-	return xfile_obj_load(sc->xfile, info, sizeof(xfs_suminfo_t),
+	return xfile_obj_load(sc->xfile, rawinfo,
+			sizeof(union xfs_suminfo_raw),
 			sumoff << XFS_WORDLOG);
 }
 
@@ -92,9 +93,10 @@ static inline int
 xfsum_store(
 	struct xfs_scrub	*sc,
 	xfs_rtsumoff_t		sumoff,
-	const xfs_suminfo_t	info)
+	const union xfs_suminfo_raw rawinfo)
 {
-	return xfile_obj_store(sc->xfile, &info, sizeof(xfs_suminfo_t),
+	return xfile_obj_store(sc->xfile, &rawinfo,
+			sizeof(union xfs_suminfo_raw),
 			sumoff << XFS_WORDLOG);
 }
 
@@ -102,13 +104,22 @@ static inline int
 xfsum_copyout(
 	struct xfs_scrub	*sc,
 	xfs_rtsumoff_t		sumoff,
-	xfs_suminfo_t		*info,
+	union xfs_suminfo_raw	*rawinfo,
 	unsigned int		nr_words)
 {
-	return xfile_obj_load(sc->xfile, info, nr_words << XFS_WORDLOG,
+	return xfile_obj_load(sc->xfile, rawinfo, nr_words << XFS_WORDLOG,
 			sumoff << XFS_WORDLOG);
 }
 
+static inline xfs_suminfo_t
+xchk_rtsum_inc(
+	struct xfs_mount	*mp,
+	union xfs_suminfo_raw	*v)
+{
+	v->old += 1;
+	return v->old;
+}
+
 /* Update the summary file to reflect the free extent that we've accumulated. */
 STATIC int
 xchk_rtsum_record_free(
@@ -123,7 +134,8 @@ xchk_rtsum_record_free(
 	xfs_filblks_t			rtlen;
 	xfs_rtsumoff_t			offs;
 	unsigned int			lenlog;
-	xfs_suminfo_t			v = 0;
+	union xfs_suminfo_raw		v;
+	xfs_suminfo_t			value;
 	int				error = 0;
 
 	if (xchk_should_terminate(sc, &error))
@@ -147,9 +159,9 @@ xchk_rtsum_record_free(
 	if (error)
 		return error;
 
-	v++;
+	value = xchk_rtsum_inc(sc->mp, &v);
 	trace_xchk_rtsum_record_free(mp, rec->ar_startext, rec->ar_extcount,
-			lenlog, offs, v);
+			lenlog, offs, value);
 
 	return xfsum_store(sc, offs, v);
 }
@@ -184,7 +196,7 @@ xchk_rtsum_compare(
 	int			nmap;
 
 	for (off = 0; off < XFS_B_TO_FSB(mp, mp->m_rsumsize); off++) {
-		xfs_suminfo_t	*ondisk_info;
+		union xfs_suminfo_raw *ondisk_info;
 		int		error = 0;
 
 		if (xchk_should_terminate(sc, &error))

fs/xfs/scrub/trace.c

@@ -13,6 +13,7 @@
 #include "xfs_inode.h"
 #include "xfs_btree.h"
 #include "xfs_ag.h"
+#include "xfs_rtbitmap.h"
 #include "scrub/scrub.h"
 #include "scrub/xfile.h"
 #include "scrub/xfarray.h"

fs/xfs/scrub/trace.h

@@ -1038,8 +1038,8 @@ TRACE_EVENT(xfarray_sort_stats,
 TRACE_EVENT(xchk_rtsum_record_free,
 	TP_PROTO(struct xfs_mount *mp, xfs_rtxnum_t start,
 		 xfs_rtbxlen_t len, unsigned int log, loff_t pos,
-		 xfs_suminfo_t v),
-	TP_ARGS(mp, start, len, log, pos, v),
+		 xfs_suminfo_t value),
+	TP_ARGS(mp, start, len, log, pos, value),
 	TP_STRUCT__entry(
 		__field(dev_t, dev)
 		__field(dev_t, rtdev)
@@ -1047,7 +1047,7 @@ TRACE_EVENT(xchk_rtsum_record_free,
 		__field(unsigned long long, len)
 		__field(unsigned int, log)
 		__field(loff_t, pos)
-		__field(xfs_suminfo_t, v)
+		__field(xfs_suminfo_t, value)
 	),
 	TP_fast_assign(
 		__entry->dev = mp->m_super->s_dev;
@@ -1056,7 +1056,7 @@ TRACE_EVENT(xchk_rtsum_record_free,
 		__entry->len = len;
 		__entry->log = log;
 		__entry->pos = pos;
-		__entry->v = v;
+		__entry->value = value;
 	),
 	TP_printk("dev %d:%d rtdev %d:%d rtx 0x%llx rtxcount 0x%llx log %u rsumpos 0x%llx sumcount %u",
 		  MAJOR(__entry->dev), MINOR(__entry->dev),
@@ -1065,7 +1065,7 @@ TRACE_EVENT(xchk_rtsum_record_free,
 		  __entry->len,
 		  __entry->log,
 		  __entry->pos,
-		  __entry->v)
+		  __entry->value)
 );
 #endif /* CONFIG_XFS_RT */
 

fs/xfs/xfs_ondisk.h

@@ -72,6 +72,10 @@ xfs_check_ondisk_structs(void)
 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_map_t,		4);
 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_name_local_t,	4);
 
+	/* realtime structures */
+	XFS_CHECK_STRUCT_SIZE(union xfs_rtword_raw,		4);
+	XFS_CHECK_STRUCT_SIZE(union xfs_suminfo_raw,		4);
+
 	/*
 	 * m68k has problems with xfs_attr_leaf_name_remote_t, but we pad it to
 	 * 4 bytes anyway so it's not obviously a problem.  Hence for the moment

fs/xfs/xfs_rtalloc.c

@@ -1001,8 +1001,7 @@ xfs_growfs_rt(
 	nrbmblocks = xfs_rtbitmap_blockcount(mp, nrextents);
 	nrextslog = xfs_highbit32(nrextents);
 	nrsumlevels = nrextslog + 1;
-	nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
-	nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
+	nrsumblocks = xfs_rtsummary_blockcount(mp, nrsumlevels, nrbmblocks);
 	nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 	/*
 	 * New summary size can't be more than half the size of
@@ -1063,10 +1062,8 @@ xfs_growfs_rt(
 		ASSERT(nsbp->sb_rextents != 0);
 		nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
 		nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
-		nrsumsize =
-			(uint)sizeof(xfs_suminfo_t) * nrsumlevels *
-			nsbp->sb_rbmblocks;
-		nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
+		nrsumblocks = xfs_rtsummary_blockcount(mp, nrsumlevels,
+				nsbp->sb_rbmblocks);
 		nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 		/*
 		 * Start a transaction, get the log reservation.
@@ -1272,6 +1269,7 @@ xfs_rtmount_init(
 	struct xfs_buf		*bp;	/* buffer for last block of subvolume */
 	struct xfs_sb		*sbp;	/* filesystem superblock copy in mount */
 	xfs_daddr_t		d;	/* address of last block of subvolume */
+	unsigned int		rsumblocks;
 	int			error;
 
 	sbp = &mp->m_sb;
@@ -1283,10 +1281,9 @@ xfs_rtmount_init(
 		return -ENODEV;
 	}
 	mp->m_rsumlevels = sbp->sb_rextslog + 1;
-	mp->m_rsumsize =
-		(uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
-		sbp->sb_rbmblocks;
-	mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
+	rsumblocks = xfs_rtsummary_blockcount(mp, mp->m_rsumlevels,
+			mp->m_sb.sb_rbmblocks);
+	mp->m_rsumsize = XFS_FSB_TO_B(mp, rsumblocks);
 	mp->m_rbmip = mp->m_rsumip = NULL;
 	/*
 	 * Check that the realtime section is an ok size.