Merge tag 'xfs-5.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull more xfs updates from Darrick Wong:
 "Except for the timestamp struct renaming patches, everything else in
  here are bug fixes:

   - Rename the log timestamp struct.

   - Remove broken transaction counter debugging that wasn't working
     correctly on very old filesystems.

   - Various fixes to make pre-lazysbcount filesystems work properly
     again.

   - Fix a free space accounting problem where we neglected to consider
     free space btree blocks that track metadata reservation space when
     deciding whether or not to allow caller to reserve space for a
     metadata update.

   - Fix incorrect pagecache clearing behavior during FUNSHARE ops.

   - Don't allow log writes if the data device is readonly"

* tag 'xfs-5.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: don't allow log writes if the data device is readonly
  xfs: fix xfs_reflink_unshare usage of filemap_write_and_wait_range
  xfs: set aside allocation btree blocks from block reservation
  xfs: introduce in-core global counter of allocbt blocks
  xfs: unconditionally read all AGFs on mounts with perag reservation
  xfs: count free space btree blocks when scrubbing pre-lazysbcount fses
  xfs: update superblock counters correctly for !lazysbcount
  xfs: don't check agf_btreeblks on pre-lazysbcount filesystems
  xfs: remove obsolete AGF counter debugging
  xfs: rename struct xfs_legacy_ictimestamp
  xfs: rename xfs_ictimestamp_t

2 files changed, 45 insertions, 2 deletions

diff --git a/fs/xfs/scrub/agheader.c b/fs/xfs/scrub/agheader.c
index 749faa17f8e2..7a2f9b5f2db5 100644
--- a/fs/xfs/scrub/agheader.c
+++ b/fs/xfs/scrub/agheader.c
@@ -416,6 +416,10 @@ xchk_agf_xref_btreeblks(
 	xfs_agblock_t		btreeblks;
 	int			error;
 
+	/* agf_btreeblks didn't exist before lazysbcount */
+	if (!xfs_sb_version_haslazysbcount(&sc->mp->m_sb))
+		return;
+
 	/* Check agf_rmap_blocks; set up for agf_btreeblks check */
 	if (sc->sa.rmap_cur) {
 		error = xfs_btree_count_blocks(sc->sa.rmap_cur, &blocks);
@@ -581,7 +585,8 @@ xchk_agf(
 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
 	if (pag->pagf_flcount != be32_to_cpu(agf->agf_flcount))
 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
-	if (pag->pagf_btreeblks != be32_to_cpu(agf->agf_btreeblks))
+	if (xfs_sb_version_haslazysbcount(&sc->mp->m_sb) &&
+	    pag->pagf_btreeblks != be32_to_cpu(agf->agf_btreeblks))
 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
 	xfs_perag_put(pag);
 
diff --git a/fs/xfs/scrub/fscounters.c b/fs/xfs/scrub/fscounters.c
index 7b4386c78fbf..f1d1a8c58853 100644
--- a/fs/xfs/scrub/fscounters.c
+++ b/fs/xfs/scrub/fscounters.c
@@ -13,6 +13,7 @@
 #include "xfs_alloc.h"
 #include "xfs_ialloc.h"
 #include "xfs_health.h"
+#include "xfs_btree.h"
 #include "scrub/scrub.h"
 #include "scrub/common.h"
 #include "scrub/trace.h"
@@ -143,6 +144,35 @@ xchk_setup_fscounters(
 	return xchk_trans_alloc(sc, 0);
 }
 
+/* Count free space btree blocks manually for pre-lazysbcount filesystems. */
+static int
+xchk_fscount_btreeblks(
+	struct xfs_scrub	*sc,
+	struct xchk_fscounters	*fsc,
+	xfs_agnumber_t		agno)
+{
+	xfs_extlen_t		blocks;
+	int			error;
+
+	error = xchk_ag_init(sc, agno, &sc->sa);
+	if (error)
+		return error;
+
+	error = xfs_btree_count_blocks(sc->sa.bno_cur, &blocks);
+	if (error)
+		goto out_free;
+	fsc->fdblocks += blocks - 1;
+
+	error = xfs_btree_count_blocks(sc->sa.cnt_cur, &blocks);
+	if (error)
+		goto out_free;
+	fsc->fdblocks += blocks - 1;
+
+out_free:
+	xchk_ag_free(sc, &sc->sa);
+	return error;
+}
+
 /*
  * Calculate what the global in-core counters ought to be from the incore
  * per-AG structure.  Callers can compare this to the actual in-core counters
@@ -182,7 +212,15 @@ retry:
 		/* Add up the free/freelist/bnobt/cntbt blocks */
 		fsc->fdblocks += pag->pagf_freeblks;
 		fsc->fdblocks += pag->pagf_flcount;
-		fsc->fdblocks += pag->pagf_btreeblks;
+		if (xfs_sb_version_haslazysbcount(&sc->mp->m_sb)) {
+			fsc->fdblocks += pag->pagf_btreeblks;
+		} else {
+			error = xchk_fscount_btreeblks(sc, fsc, agno);
+			if (error) {
+				xfs_perag_put(pag);
+				break;
+			}
+		}
 
 		/*
 		 * Per-AG reservations are taken out of the incore counters,