xfs: Pre-calculate per-AG agbno geometry

There is a lot of overhead in functions like xfs_verify_agbno() that
repeatedly calculate the geometry limits of an AG. These can be
pre-calculated as they are static and the verification context has
a per-ag context it can quickly reference.

In the case of xfs_verify_agbno(), we now always have a perag
context handy, so we can store the AG length and the minimum valid
block in the AG in the perag. This means we don't have to calculate
it on every call and it can be inlined in callers if we move it
to xfs_ag.h.

Move xfs_ag_block_count() to xfs_ag.c because it's really a
per-ag function and not an XFS type function. We need a little
bit of rework that is specific to xfs_initialise_perag() to allow
growfs to calculate the new perag sizes before we've updated the
primary superblock during the grow (chicken/egg situation).

Note that we leave the original xfs_verify_agbno in place in
xfs_types.c as a static function as other callers in that file do
not have per-ag contexts so still need to go the long way. It's been
renamed to xfs_verify_agno_agbno() to indicate it takes both an agno
and an agbno to differentiate it from new function.

Future commits will make similar changes for other per-ag geometry
validation functions.

Further:

$ size --totals fs/xfs/built-in.a
	   text    data     bss     dec     hex filename
before	1483006	 329588	    572	1813166	 1baaae	(TOTALS)
after	1482185	 329588	    572	1812345	 1ba779	(TOTALS)

This rework reduces the binary size by ~820 bytes, indicating
that much less work is being done to bounds check the agbno values
against on per-ag geometry information.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

6 files changed, 23 insertions, 29 deletions

diff --git a/fs/xfs/scrub/agheader.c b/fs/xfs/scrub/agheader.c
index 90aebfe9dc5f..181bba5f9b8f 100644
--- a/fs/xfs/scrub/agheader.c
+++ b/fs/xfs/scrub/agheader.c
@@ -541,16 +541,16 @@ xchk_agf(
 
 	/* Check the AG length */
 	eoag = be32_to_cpu(agf->agf_length);
-	if (eoag != xfs_ag_block_count(mp, agno))
+	if (eoag != pag->block_count)
 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
 
 	/* Check the AGF btree roots and levels */
 	agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_BNO]);
-	if (!xfs_verify_agbno(mp, agno, agbno))
+	if (!xfs_verify_agbno(pag, agbno))
 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
 
 	agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_CNT]);
-	if (!xfs_verify_agbno(mp, agno, agbno))
+	if (!xfs_verify_agbno(pag, agbno))
 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
 
 	level = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
@@ -563,7 +563,7 @@ xchk_agf(
 
 	if (xfs_has_rmapbt(mp)) {
 		agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_RMAP]);
-		if (!xfs_verify_agbno(mp, agno, agbno))
+		if (!xfs_verify_agbno(pag, agbno))
 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
 
 		level = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]);
@@ -573,7 +573,7 @@ xchk_agf(
 
 	if (xfs_has_reflink(mp)) {
 		agbno = be32_to_cpu(agf->agf_refcount_root);
-		if (!xfs_verify_agbno(mp, agno, agbno))
+		if (!xfs_verify_agbno(pag, agbno))
 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
 
 		level = be32_to_cpu(agf->agf_refcount_level);
@@ -639,9 +639,8 @@ xchk_agfl_block(
 {
 	struct xchk_agfl_info	*sai = priv;
 	struct xfs_scrub	*sc = sai->sc;
-	xfs_agnumber_t		agno = sc->sa.pag->pag_agno;
 
-	if (xfs_verify_agbno(mp, agno, agbno) &&
+	if (xfs_verify_agbno(sc->sa.pag, agbno) &&
 	    sai->nr_entries < sai->sz_entries)
 		sai->entries[sai->nr_entries++] = agbno;
 	else
@@ -871,12 +870,12 @@ xchk_agi(
 
 	/* Check the AG length */
 	eoag = be32_to_cpu(agi->agi_length);
-	if (eoag != xfs_ag_block_count(mp, agno))
+	if (eoag != pag->block_count)
 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
 
 	/* Check btree roots and levels */
 	agbno = be32_to_cpu(agi->agi_root);
-	if (!xfs_verify_agbno(mp, agno, agbno))
+	if (!xfs_verify_agbno(pag, agbno))
 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
 
 	level = be32_to_cpu(agi->agi_level);
@@ -885,7 +884,7 @@ xchk_agi(
 
 	if (xfs_has_finobt(mp)) {
 		agbno = be32_to_cpu(agi->agi_free_root);
-		if (!xfs_verify_agbno(mp, agno, agbno))
+		if (!xfs_verify_agbno(pag, agbno))
 			xchk_block_set_corrupt(sc, sc->sa.agi_bp);
 
 		level = be32_to_cpu(agi->agi_free_level);
diff --git a/fs/xfs/scrub/agheader_repair.c b/fs/xfs/scrub/agheader_repair.c
index 10ac1118a595..ba012a5da0bf 100644
--- a/fs/xfs/scrub/agheader_repair.c
+++ b/fs/xfs/scrub/agheader_repair.c
@@ -106,7 +106,7 @@ xrep_agf_check_agfl_block(
 {
 	struct xfs_scrub	*sc = priv;
 
-	if (!xfs_verify_agbno(mp, sc->sa.pag->pag_agno, agbno))
+	if (!xfs_verify_agbno(sc->sa.pag, agbno))
 		return -EFSCORRUPTED;
 	return 0;
 }
@@ -130,10 +130,7 @@ xrep_check_btree_root(
 	struct xfs_scrub		*sc,
 	struct xrep_find_ag_btree	*fab)
 {
-	struct xfs_mount		*mp = sc->mp;
-	xfs_agnumber_t			agno = sc->sm->sm_agno;
-
-	return xfs_verify_agbno(mp, agno, fab->root) &&
+	return xfs_verify_agbno(sc->sa.pag, fab->root) &&
 	       fab->height <= fab->maxlevels;
 }
 
diff --git a/fs/xfs/scrub/alloc.c b/fs/xfs/scrub/alloc.c
index 87518e1292f8..ab427b4d7fe0 100644
--- a/fs/xfs/scrub/alloc.c
+++ b/fs/xfs/scrub/alloc.c
@@ -93,8 +93,7 @@ xchk_allocbt_rec(
 	struct xchk_btree	*bs,
 	const union xfs_btree_rec *rec)
 {
-	struct xfs_mount	*mp = bs->cur->bc_mp;
-	xfs_agnumber_t		agno = bs->cur->bc_ag.pag->pag_agno;
+	struct xfs_perag	*pag = bs->cur->bc_ag.pag;
 	xfs_agblock_t		bno;
 	xfs_extlen_t		len;
 
@@ -102,8 +101,8 @@ xchk_allocbt_rec(
 	len = be32_to_cpu(rec->alloc.ar_blockcount);
 
 	if (bno + len <= bno ||
-	    !xfs_verify_agbno(mp, agno, bno) ||
-	    !xfs_verify_agbno(mp, agno, bno + len - 1))
+	    !xfs_verify_agbno(pag, bno) ||
+	    !xfs_verify_agbno(pag, bno + len - 1))
 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 
 	xchk_allocbt_xref(bs->sc, bno, len);
diff --git a/fs/xfs/scrub/ialloc.c b/fs/xfs/scrub/ialloc.c
index 00848ee542fb..b80a54be8634 100644
--- a/fs/xfs/scrub/ialloc.c
+++ b/fs/xfs/scrub/ialloc.c
@@ -104,13 +104,13 @@ xchk_iallocbt_chunk(
 	xfs_extlen_t			len)
 {
 	struct xfs_mount		*mp = bs->cur->bc_mp;
-	xfs_agnumber_t			agno = bs->cur->bc_ag.pag->pag_agno;
+	struct xfs_perag		*pag = bs->cur->bc_ag.pag;
 	xfs_agblock_t			bno;
 
 	bno = XFS_AGINO_TO_AGBNO(mp, agino);
 	if (bno + len <= bno ||
-	    !xfs_verify_agbno(mp, agno, bno) ||
-	    !xfs_verify_agbno(mp, agno, bno + len - 1))
+	    !xfs_verify_agbno(pag, bno) ||
+	    !xfs_verify_agbno(pag, bno + len - 1))
 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 
 	xchk_iallocbt_chunk_xref(bs->sc, irec, agino, bno, len);
diff --git a/fs/xfs/scrub/refcount.c b/fs/xfs/scrub/refcount.c
index 2744eecdbaf0..3f82a1a1f390 100644
--- a/fs/xfs/scrub/refcount.c
+++ b/fs/xfs/scrub/refcount.c
@@ -332,9 +332,8 @@ xchk_refcountbt_rec(
 	struct xchk_btree	*bs,
 	const union xfs_btree_rec *rec)
 {
-	struct xfs_mount	*mp = bs->cur->bc_mp;
 	xfs_agblock_t		*cow_blocks = bs->private;
-	xfs_agnumber_t		agno = bs->cur->bc_ag.pag->pag_agno;
+	struct xfs_perag	*pag = bs->cur->bc_ag.pag;
 	xfs_agblock_t		bno;
 	xfs_extlen_t		len;
 	xfs_nlink_t		refcount;
@@ -354,8 +353,8 @@ xchk_refcountbt_rec(
 	/* Check the extent. */
 	bno &= ~XFS_REFC_COW_START;
 	if (bno + len <= bno ||
-	    !xfs_verify_agbno(mp, agno, bno) ||
-	    !xfs_verify_agbno(mp, agno, bno + len - 1))
+	    !xfs_verify_agbno(pag, bno) ||
+	    !xfs_verify_agbno(pag, bno + len - 1))
 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 
 	if (refcount == 0)
diff --git a/fs/xfs/scrub/rmap.c b/fs/xfs/scrub/rmap.c
index 8dae0345c7df..229826b2e1c0 100644
--- a/fs/xfs/scrub/rmap.c
+++ b/fs/xfs/scrub/rmap.c
@@ -92,7 +92,7 @@ xchk_rmapbt_rec(
 {
 	struct xfs_mount	*mp = bs->cur->bc_mp;
 	struct xfs_rmap_irec	irec;
-	xfs_agnumber_t		agno = bs->cur->bc_ag.pag->pag_agno;
+	struct xfs_perag	*pag = bs->cur->bc_ag.pag;
 	bool			non_inode;
 	bool			is_unwritten;
 	bool			is_bmbt;
@@ -121,8 +121,8 @@ xchk_rmapbt_rec(
 		 * Otherwise we must point somewhere past the static metadata
 		 * but before the end of the FS.  Run the regular check.
 		 */
-		if (!xfs_verify_agbno(mp, agno, irec.rm_startblock) ||
-		    !xfs_verify_agbno(mp, agno, irec.rm_startblock +
+		if (!xfs_verify_agbno(pag, irec.rm_startblock) ||
+		    !xfs_verify_agbno(pag, irec.rm_startblock +
 				irec.rm_blockcount - 1))
 			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 	}