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From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: linux-xfs@vger.kernel.org
Subject: [PATCH v2 19/21] xfs: cross-reference refcount btree during scrub
Date: Tue, 9 Jan 2018 13:25:47 -0800	[thread overview]
Message-ID: <20180109212547.GN5602@magnolia> (raw)
In-Reply-To: <151398988926.18741.14757152372859283463.stgit@magnolia>

From: Darrick J. Wong <darrick.wong@oracle.com>

During metadata btree scrub, we should cross-reference with the
reference counts.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
v2: streamline scrubber arguments, remove stack allocated objects
---
 fs/xfs/scrub/agheader.c |   13 ++++++++
 fs/xfs/scrub/alloc.c    |    1 +
 fs/xfs/scrub/bmap.c     |   77 +++++++++++++++++++++++++++++++++++++++++++++++
 fs/xfs/scrub/ialloc.c   |    1 +
 fs/xfs/scrub/inode.c    |    1 +
 fs/xfs/scrub/refcount.c |   65 ++++++++++++++++++++++++++++++++++++++++
 fs/xfs/scrub/rmap.c     |   38 +++++++++++++++++++++++
 fs/xfs/scrub/scrub.h    |    4 ++
 8 files changed, 200 insertions(+)

diff --git a/fs/xfs/scrub/agheader.c b/fs/xfs/scrub/agheader.c
index 6bc8121..808ef3c 100644
--- a/fs/xfs/scrub/agheader.c
+++ b/fs/xfs/scrub/agheader.c
@@ -127,6 +127,7 @@ xfs_scrub_superblock_xref(
 	xfs_scrub_xref_not_inodes(sc, agbno, 1);
 	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_FS);
 	xfs_scrub_xref_owned_by(sc, agbno, 1, &oinfo);
+	xfs_scrub_xref_not_shared(sc, agbno, 1);
 
 	/* scrub teardown will take care of sc->sa for us */
 }
@@ -556,6 +557,15 @@ xfs_scrub_agf_xref(
 	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_FS);
 	xfs_scrub_xref_owned_by(sc, agbno, 1, &oinfo);
 	xfs_scrub_agf_xref_btreeblks(sc);
+	xfs_scrub_xref_not_shared(sc, agbno, 1);
+
+	/* Check agf_refcount_blocks against tree size */
+	if (sc->sa.refc_cur) {
+		error = xfs_btree_count_blocks(sc->sa.refc_cur, &blocks);
+		if (xfs_scrub_should_check_xref(sc, &error, &sc->sa.refc_cur) &&
+		    blocks != be32_to_cpu(agf->agf_refcount_blocks))
+			xfs_scrub_block_xref_set_corrupt(sc, sc->sa.agf_bp);
+	}
 
 	/* scrub teardown will take care of sc->sa for us */
 }
@@ -665,6 +675,7 @@ xfs_scrub_agfl_block_xref(
 	xfs_scrub_xref_is_used_space(sc, agbno, 1);
 	xfs_scrub_xref_not_inodes(sc, agbno, 1);
 	xfs_scrub_xref_owned_by(sc, agbno, 1, oinfo);
+	xfs_scrub_xref_not_shared(sc, agbno, 1);
 }
 
 /* Scrub an AGFL block. */
@@ -723,6 +734,7 @@ xfs_scrub_agfl_xref(
 	xfs_scrub_xref_not_inodes(sc, agbno, 1);
 	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_FS);
 	xfs_scrub_xref_owned_by(sc, agbno, 1, &oinfo);
+	xfs_scrub_xref_not_shared(sc, agbno, 1);
 
 	/*
 	 * Scrub teardown will take care of sc->sa for us.  Leave sc->sa
@@ -835,6 +847,7 @@ xfs_scrub_agi_xref(
 
 	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_FS);
 	xfs_scrub_xref_owned_by(sc, agbno, 1, &oinfo);
+	xfs_scrub_xref_not_shared(sc, agbno, 1);
 
 	/* scrub teardown will take care of sc->sa for us */
 }
diff --git a/fs/xfs/scrub/alloc.c b/fs/xfs/scrub/alloc.c
index b4defa4..3f5168f 100644
--- a/fs/xfs/scrub/alloc.c
+++ b/fs/xfs/scrub/alloc.c
@@ -106,6 +106,7 @@ xfs_scrub_allocbt_xref(
 	xfs_scrub_allocbt_xref_other(sc, agbno, len);
 	xfs_scrub_xref_not_inodes(sc, agbno, len);
 	xfs_scrub_xref_no_rmap(sc, agbno, len);
+	xfs_scrub_xref_not_shared(sc, agbno, len);
 }
 
 /* Scrub a bnobt/cntbt record. */
diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
index ef7b461..5c34e025 100644
--- a/fs/xfs/scrub/bmap.c
+++ b/fs/xfs/scrub/bmap.c
@@ -37,6 +37,7 @@
 #include "xfs_bmap_util.h"
 #include "xfs_bmap_btree.h"
 #include "xfs_rmap.h"
+#include "xfs_refcount.h"
 #include "scrub/xfs_scrub.h"
 #include "scrub/scrub.h"
 #include "scrub/common.h"
@@ -202,6 +203,71 @@ xfs_scrub_bmap_xref_rmap(
 				irec->br_startoff);
 }
 
+/* Make sure the refcount records match this data fork extent. */
+STATIC void
+xfs_scrub_bmap_xref_refcount_data(
+	struct xfs_scrub_bmap_info	*info,
+	struct xfs_bmbt_irec		*irec,
+	xfs_fsblock_t			bno)
+{
+	xfs_agblock_t			fbno;
+	xfs_extlen_t			flen;
+	int				error;
+
+	if (!info->sc->sa.refc_cur)
+		return;
+
+	/* If this is shared, the inode flag must be set. */
+	error = xfs_refcount_find_shared(info->sc->sa.refc_cur, bno,
+			irec->br_blockcount, &fbno, &flen, false);
+	if (!xfs_scrub_should_check_xref(info->sc, &error,
+			&info->sc->sa.refc_cur))
+		return;
+
+	if (flen != 0 && !xfs_is_reflink_inode(info->sc->ip))
+		xfs_scrub_fblock_xref_set_corrupt(info->sc, info->whichfork,
+				irec->br_startoff);
+}
+
+/* Make sure the refcount records match this attr fork extent. */
+STATIC void
+xfs_scrub_bmap_xref_refcount_attr(
+	struct xfs_scrub_bmap_info	*info,
+	struct xfs_bmbt_irec		*irec,
+	xfs_fsblock_t			bno)
+{
+	xfs_agblock_t			fbno;
+	xfs_extlen_t			flen;
+	int				error;
+
+	if (!info->sc->sa.refc_cur)
+		return;
+
+	/* No shared attr fork extents */
+	error = xfs_refcount_find_shared(info->sc->sa.refc_cur, bno,
+			irec->br_blockcount, &fbno, &flen, false);
+	if (!xfs_scrub_should_check_xref(info->sc, &error,
+			&info->sc->sa.refc_cur))
+		return;
+
+	if (flen != 0)
+		xfs_scrub_fblock_xref_set_corrupt(info->sc, info->whichfork,
+				irec->br_startoff);
+}
+
+/* Make sure the refcount records match this CoW fork extent. */
+STATIC void
+xfs_scrub_bmap_xref_refcount_cow(
+	struct xfs_scrub_bmap_info	*info,
+	struct xfs_bmbt_irec		*irec,
+	xfs_fsblock_t			bno)
+{
+	if (!info->sc->sa.refc_cur)
+		return;
+
+	xfs_scrub_xref_has_cow_staging(info->sc, bno, irec->br_blockcount);
+}
+
 /* Cross-reference a single rtdev extent record. */
 STATIC void
 xfs_scrub_bmap_rt_extent_xref(
@@ -243,6 +309,17 @@ xfs_scrub_bmap_extent_xref(
 	xfs_scrub_xref_is_used_space(info->sc, agbno, len);
 	xfs_scrub_xref_not_inodes(info->sc, agbno, len);
 	xfs_scrub_bmap_xref_rmap(info, irec, agbno);
+	switch (info->whichfork) {
+	case XFS_DATA_FORK:
+		xfs_scrub_bmap_xref_refcount_data(info, irec, agbno);
+		break;
+	case XFS_ATTR_FORK:
+		xfs_scrub_bmap_xref_refcount_attr(info, irec, agbno);
+		break;
+	case XFS_COW_FORK:
+		xfs_scrub_bmap_xref_refcount_cow(info, irec, agbno);
+		break;
+	}
 
 	xfs_scrub_ag_free(info->sc, &info->sc->sa);
 }
diff --git a/fs/xfs/scrub/ialloc.c b/fs/xfs/scrub/ialloc.c
index 30603b4..fb16314 100644
--- a/fs/xfs/scrub/ialloc.c
+++ b/fs/xfs/scrub/ialloc.c
@@ -97,6 +97,7 @@ xfs_scrub_iallocbt_chunk_xref(
 
 	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_INODES);
 	xfs_scrub_xref_owned_by(sc, agbno, len, &oinfo);
+	xfs_scrub_xref_not_shared(sc, agbno, len);
 }
 
 /* Is this chunk worth checking? */
diff --git a/fs/xfs/scrub/inode.c b/fs/xfs/scrub/inode.c
index fc546f2..f12586c 100644
--- a/fs/xfs/scrub/inode.c
+++ b/fs/xfs/scrub/inode.c
@@ -652,6 +652,7 @@ xfs_scrub_inode_xref(
 	xfs_scrub_inode_xref_finobt(sc, ino);
 	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_INODES);
 	xfs_scrub_xref_owned_by(sc, agbno, 1, &oinfo);
+	xfs_scrub_xref_not_shared(sc, agbno, 1);
 
 	xfs_scrub_ag_free(sc, &sc->sa);
 }
diff --git a/fs/xfs/scrub/refcount.c b/fs/xfs/scrub/refcount.c
index df18e47..6e5b12a 100644
--- a/fs/xfs/scrub/refcount.c
+++ b/fs/xfs/scrub/refcount.c
@@ -31,6 +31,7 @@
 #include "xfs_sb.h"
 #include "xfs_alloc.h"
 #include "xfs_rmap.h"
+#include "xfs_refcount.h"
 #include "scrub/xfs_scrub.h"
 #include "scrub/scrub.h"
 #include "scrub/common.h"
@@ -428,3 +429,67 @@ xfs_scrub_refcountbt(
 
 	return error;
 }
+
+/* xref check that a cow staging extent is marked in the refcountbt. */
+void
+xfs_scrub_xref_has_cow_staging(
+	struct xfs_scrub_context	*sc,
+	xfs_agblock_t			bno,
+	xfs_extlen_t			len)
+{
+	struct xfs_refcount_irec	rc;
+	bool				has_cowflag;
+	int				has_refcount;
+	int				error;
+
+	if (!sc->sa.refc_cur)
+		return;
+
+	/* Find the CoW staging extent. */
+	error = xfs_refcount_lookup_le(sc->sa.refc_cur,
+			bno + XFS_REFC_COW_START, &has_refcount);
+	if (!xfs_scrub_should_check_xref(sc, &error, &sc->sa.refc_cur))
+		return;
+	if (!has_refcount) {
+		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
+		return;
+	}
+
+	error = xfs_refcount_get_rec(sc->sa.refc_cur, &rc, &has_refcount);
+	if (!xfs_scrub_should_check_xref(sc, &error, &sc->sa.refc_cur))
+		return;
+	if (!has_refcount) {
+		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
+		return;
+	}
+
+	/* CoW flag must be set, refcount must be 1. */
+	has_cowflag = (rc.rc_startblock & XFS_REFC_COW_START);
+	if (!has_cowflag || rc.rc_refcount != 1)
+		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
+
+	/* Must be at least as long as what was passed in */
+	if (rc.rc_blockcount < len)
+		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
+}
+
+/*
+ * xref check that the extent is not shared.  Only file data blocks
+ * can have multiple owners.
+ */
+void
+xfs_scrub_xref_not_shared(
+	struct xfs_scrub_context	*sc,
+	xfs_agblock_t			bno,
+	xfs_extlen_t			len)
+{
+	bool				shared;
+	int				error;
+
+	if (!sc->sa.refc_cur)
+		return;
+
+	error = xfs_refcount_has_record(sc->sa.refc_cur, bno, len, &shared);
+	if (xfs_scrub_should_check_xref(sc, &error, &sc->sa.refc_cur) && shared)
+		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
+}
diff --git a/fs/xfs/scrub/rmap.c b/fs/xfs/scrub/rmap.c
index 8421c6e..e217f98 100644
--- a/fs/xfs/scrub/rmap.c
+++ b/fs/xfs/scrub/rmap.c
@@ -32,6 +32,7 @@
 #include "xfs_alloc.h"
 #include "xfs_ialloc.h"
 #include "xfs_rmap.h"
+#include "xfs_refcount.h"
 #include "scrub/xfs_scrub.h"
 #include "scrub/scrub.h"
 #include "scrub/common.h"
@@ -51,6 +52,42 @@ xfs_scrub_setup_ag_rmapbt(
 
 /* Reverse-mapping scrubber. */
 
+/* Cross-reference a rmap against the refcount btree. */
+STATIC void
+xfs_scrub_rmapbt_xref_refc(
+	struct xfs_scrub_context	*sc,
+	struct xfs_rmap_irec		*irec)
+{
+	xfs_agblock_t			fbno;
+	xfs_extlen_t			flen;
+	bool				non_inode;
+	bool				is_bmbt;
+	bool				is_attr;
+	bool				is_unwritten;
+	int				error;
+
+	if (!sc->sa.refc_cur)
+		return;
+
+	if (irec->rm_owner == XFS_RMAP_OWN_COW) {
+		xfs_scrub_xref_has_cow_staging(sc, irec->rm_startblock,
+				irec->rm_blockcount);
+		return;
+	}
+
+	non_inode = XFS_RMAP_NON_INODE_OWNER(irec->rm_owner);
+	is_bmbt = irec->rm_flags & XFS_RMAP_BMBT_BLOCK;
+	is_attr = irec->rm_flags & XFS_RMAP_ATTR_FORK;
+	is_unwritten = irec->rm_flags & XFS_RMAP_UNWRITTEN;
+
+	/* If this is shared, must be a data fork extent. */
+	error = xfs_refcount_find_shared(sc->sa.refc_cur, irec->rm_startblock,
+			irec->rm_blockcount, &fbno, &flen, false);
+	if (xfs_scrub_should_check_xref(sc, &error, &sc->sa.refc_cur) &&
+	    flen != 0 && (non_inode || is_attr || is_bmbt || is_unwritten))
+		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
+}
+
 /* Cross-reference with the other btrees. */
 STATIC void
 xfs_scrub_rmapbt_xref(
@@ -68,6 +105,7 @@ xfs_scrub_rmapbt_xref(
 		xfs_scrub_xref_are_inodes(sc, agbno, len);
 	else
 		xfs_scrub_xref_not_inodes(sc, agbno, len);
+	xfs_scrub_rmapbt_xref_refc(sc, irec);
 }
 
 /* Scrub an rmapbt record. */
diff --git a/fs/xfs/scrub/scrub.h b/fs/xfs/scrub/scrub.h
index 53cc526..06c2d17 100644
--- a/fs/xfs/scrub/scrub.h
+++ b/fs/xfs/scrub/scrub.h
@@ -138,5 +138,9 @@ void xfs_scrub_xref_not_owned_by(struct xfs_scrub_context *sc,
 		struct xfs_owner_info *oinfo);
 void xfs_scrub_xref_no_rmap(struct xfs_scrub_context *sc,
 		xfs_agblock_t bno, xfs_extlen_t len);
+void xfs_scrub_xref_has_cow_staging(struct xfs_scrub_context *sc,
+		xfs_agblock_t bno, xfs_extlen_t len);
+void xfs_scrub_xref_not_shared(struct xfs_scrub_context *sc,
+		xfs_agblock_t bno, xfs_extlen_t len);
 
 #endif	/* __XFS_SCRUB_SCRUB_H__ */

  reply	other threads:[~2018-01-09 21:26 UTC|newest]

Thread overview: 94+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-23  0:42 [PATCH v11 00/21] xfs: online scrub xref support Darrick J. Wong
2017-12-23  0:42 ` [PATCH 01/21] xfs: ignore agfl read errors when not scrubbing agfl Darrick J. Wong
2018-01-05  1:12   ` Dave Chinner
2017-12-23  0:43 ` [PATCH 02/21] xfs: catch a few more error codes when scrubbing secondary sb Darrick J. Wong
2018-01-05  1:17   ` Dave Chinner
2018-01-05  1:24     ` Darrick J. Wong
2018-01-05  2:10       ` Dave Chinner
2017-12-23  0:43 ` [PATCH 03/21] xfs: xfs_scrub_bmap should use for_each_xfs_iext Darrick J. Wong
2018-01-05  1:17   ` Dave Chinner
2017-12-23  0:43 ` [PATCH 04/21] xfs: always grab transaction when scrubbing inode Darrick J. Wong
2018-01-05  1:18   ` Dave Chinner
2017-12-23  0:43 ` [PATCH 05/21] xfs: distinguish between corrupt inode and invalid inum in xfs_scrub_get_inode Darrick J. Wong
2018-01-05  1:23   ` Dave Chinner
2017-12-23  0:43 ` [PATCH 06/21] xfs: add scrub cross-referencing helpers for the free space btrees Darrick J. Wong
2018-01-05  1:29   ` Dave Chinner
2017-12-23  0:43 ` [PATCH 07/21] xfs: add scrub cross-referencing helpers for the inode btrees Darrick J. Wong
2018-01-05  1:36   ` Dave Chinner
2018-01-05  2:19     ` Darrick J. Wong
2018-01-05 21:51   ` [PATCH v2 " Darrick J. Wong
2018-01-16 23:05     ` Darrick J. Wong
2018-01-17  0:36       ` Dave Chinner
2017-12-23  0:43 ` [PATCH 08/21] xfs: add scrub cross-referencing helpers for the rmap btrees Darrick J. Wong
2018-01-05  1:40   ` Dave Chinner
2018-01-05  2:49     ` Darrick J. Wong
2018-01-05  3:38       ` Dave Chinner
2018-01-05 21:53   ` [PATCH v2 " Darrick J. Wong
2018-01-06 20:46     ` Dave Chinner
2017-12-23  0:43 ` [PATCH 09/21] xfs: add scrub cross-referencing helpers for the refcount btrees Darrick J. Wong
2018-01-05  1:41   ` Dave Chinner
2017-12-23  0:43 ` [PATCH 10/21] xfs: set up scrub cross-referencing helpers Darrick J. Wong
2018-01-05  2:08   ` Dave Chinner
2018-01-05  3:05     ` Darrick J. Wong
2018-01-05 21:54   ` [PATCH v2 " Darrick J. Wong
2018-01-16 23:06     ` Darrick J. Wong
2018-01-17  0:41     ` Dave Chinner
2017-12-23  0:44 ` [PATCH 11/21] xfs: fix a few erroneous process_error calls in the scrubbers Darrick J. Wong
2018-01-05  2:11   ` Dave Chinner
2017-12-23  0:44 ` [PATCH 12/21] xfs: check btree block ownership with bnobt/rmapbt when scrubbing btree Darrick J. Wong
2018-01-05  2:24   ` Dave Chinner
2018-01-05  2:53     ` Darrick J. Wong
2018-01-05  3:39       ` Dave Chinner
2017-12-23  0:44 ` [PATCH 13/21] xfs: introduce scrubber cross-referencing stubs Darrick J. Wong
2018-01-08 23:36   ` Dave Chinner
2018-01-08 23:59     ` Darrick J. Wong
2018-01-09 21:00   ` [PATCH v2 " Darrick J. Wong
2018-01-10  0:12     ` Dave Chinner
2017-12-23  0:44 ` [PATCH 14/21] xfs: cross-reference with the bnobt Darrick J. Wong
2018-01-08 23:51   ` Dave Chinner
2018-01-09  0:34     ` Darrick J. Wong
2018-01-09  0:57       ` Dave Chinner
2018-01-09 21:15   ` [PATCH v2 " Darrick J. Wong
2018-01-10  0:15     ` Dave Chinner
2017-12-23  0:44 ` [PATCH 15/21] xfs: cross-reference bnobt records with cntbt Darrick J. Wong
2018-01-08 23:55   ` Dave Chinner
2018-01-09  0:37     ` Darrick J. Wong
2018-01-09 21:20   ` [PATCH v2 " Darrick J. Wong
2018-01-10  0:19     ` Dave Chinner
2017-12-23  0:44 ` [PATCH 16/21] xfs: cross-reference inode btrees during scrub Darrick J. Wong
2018-01-09 21:22   ` [PATCH v2 " Darrick J. Wong
2018-01-15 22:17     ` Dave Chinner
2018-01-16  6:30       ` Darrick J. Wong
2018-01-16 23:23   ` [PATCH v3 " Darrick J. Wong
2018-01-17  0:44     ` Dave Chinner
2017-12-23  0:44 ` [PATCH 17/21] xfs: cross-reference reverse-mapping btree Darrick J. Wong
2018-01-09 21:24   ` [PATCH v2 " Darrick J. Wong
2018-01-15 23:04     ` Dave Chinner
2018-01-16  6:38       ` Darrick J. Wong
2018-01-16 23:25   ` [PATCH v3 " Darrick J. Wong
2018-01-17  0:52     ` Dave Chinner
2017-12-23  0:44 ` [PATCH 18/21] xfs: cross-reference the rmapbt data with the refcountbt Darrick J. Wong
2018-01-09 21:25   ` [PATCH v2 " Darrick J. Wong
2018-01-15 23:49     ` Dave Chinner
2018-01-16  6:49       ` Darrick J. Wong
2018-01-16 19:47         ` Darrick J. Wong
2018-01-16 23:26   ` [PATCH v3 " Darrick J. Wong
2018-01-17  1:00     ` Dave Chinner
2018-01-17  1:11       ` Darrick J. Wong
2017-12-23  0:44 ` [PATCH 19/21] xfs: cross-reference refcount btree during scrub Darrick J. Wong
2018-01-09 21:25   ` Darrick J. Wong [this message]
2018-01-16  2:44     ` [PATCH v2 " Dave Chinner
2018-01-16  6:52       ` Darrick J. Wong
2018-01-16 20:26         ` Darrick J. Wong
2018-01-16 23:27   ` [PATCH v3 " Darrick J. Wong
2018-01-17  1:02     ` Dave Chinner
2017-12-23  0:44 ` [PATCH 20/21] xfs: cross-reference the realtime bitmap Darrick J. Wong
2018-01-09 21:26   ` [PATCH v2 " Darrick J. Wong
2018-01-16  2:57     ` Dave Chinner
2018-01-16  6:55       ` Darrick J. Wong
2018-01-16 23:27   ` [PATCH v3 " Darrick J. Wong
2018-01-17  1:03     ` Dave Chinner
2017-12-23  0:45 ` [PATCH 21/21] xfs: cross-reference the block mappings when possible Darrick J. Wong
2018-01-09 21:26   ` [PATCH v2 " Darrick J. Wong
2018-01-16  2:58     ` Dave Chinner
2018-01-16  6:55       ` Darrick J. Wong

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