xfs: scrub realtime bitmap/summary

Perform simple tests of the realtime bitmap and summary.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

fs/xfs/Makefile

@@ -159,4 +159,6 @@ xfs-y				+= $(addprefix scrub/, \
 				   scrub.o \
 				   symlink.o \
 				   )
+
+xfs-$(CONFIG_XFS_RT)		+= scrub/rtbitmap.o
 endif

fs/xfs/libxfs/xfs_format.h

@@ -315,6 +315,11 @@ static inline bool xfs_sb_good_version(struct xfs_sb *sbp)
 	return false;
 }
 
+static inline bool xfs_sb_version_hasrealtime(struct xfs_sb *sbp)
+{
+	return sbp->sb_rblocks > 0;
+}
+
 /*
  * Detect a mismatched features2 field.  Older kernels read/wrote
  * this into the wrong slot, so to be safe we keep them in sync.

fs/xfs/libxfs/xfs_fs.h

@@ -502,9 +502,11 @@ struct xfs_scrub_metadata {
 #define XFS_SCRUB_TYPE_XATTR	16	/* extended attribute */
 #define XFS_SCRUB_TYPE_SYMLINK	17	/* symbolic link */
 #define XFS_SCRUB_TYPE_PARENT	18	/* parent pointers */
+#define XFS_SCRUB_TYPE_RTBITMAP	19	/* realtime bitmap */
+#define XFS_SCRUB_TYPE_RTSUM	20	/* realtime summary */
 
 /* Number of scrub subcommands. */
-#define XFS_SCRUB_TYPE_NR	19
+#define XFS_SCRUB_TYPE_NR	21
 
 /* i: Repair this metadata. */
 #define XFS_SCRUB_IFLAG_REPAIR		(1 << 0)

fs/xfs/scrub/common.h

@@ -101,6 +101,15 @@ int xfs_scrub_setup_symlink(struct xfs_scrub_context *sc,
 			    struct xfs_inode *ip);
 int xfs_scrub_setup_parent(struct xfs_scrub_context *sc,
 			   struct xfs_inode *ip);
+#ifdef CONFIG_XFS_RT
+int xfs_scrub_setup_rt(struct xfs_scrub_context *sc, struct xfs_inode *ip);
+#else
+static inline int
+xfs_scrub_setup_rt(struct xfs_scrub_context *sc, struct xfs_inode *ip)
+{
+	return -ENOENT;
+}
+#endif
 
 void xfs_scrub_ag_free(struct xfs_scrub_context *sc, struct xfs_scrub_ag *sa);
 int xfs_scrub_ag_init(struct xfs_scrub_context *sc, xfs_agnumber_t agno,

fs/xfs/scrub/rtbitmap.c

+/*
+ * Copyright (C) 2017 Oracle.  All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_btree.h"
+#include "xfs_bit.h"
+#include "xfs_log_format.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_alloc.h"
+#include "xfs_rtalloc.h"
+#include "xfs_inode.h"
+#include "scrub/xfs_scrub.h"
+#include "scrub/scrub.h"
+#include "scrub/common.h"
+#include "scrub/trace.h"
+
+/* Set us up with the realtime metadata locked. */
+int
+xfs_scrub_setup_rt(
+	struct xfs_scrub_context	*sc,
+	struct xfs_inode		*ip)
+{
+	struct xfs_mount		*mp = sc->mp;
+	int				error = 0;
+
+	/*
+	 * If userspace gave us an AG number or inode data, they don't
+	 * know what they're doing.  Get out.
+	 */
+	if (sc->sm->sm_agno || sc->sm->sm_ino || sc->sm->sm_gen)
+		return -EINVAL;
+
+	error = xfs_scrub_setup_fs(sc, ip);
+	if (error)
+		return error;
+
+	sc->ilock_flags = XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP;
+	sc->ip = mp->m_rbmip;
+	xfs_ilock(sc->ip, sc->ilock_flags);
+
+	return 0;
+}
+
+/* Realtime bitmap. */
+
+/* Scrub a free extent record from the realtime bitmap. */
+STATIC int
+xfs_scrub_rtbitmap_rec(
+	struct xfs_trans		*tp,
+	struct xfs_rtalloc_rec		*rec,
+	void				*priv)
+{
+	struct xfs_scrub_context	*sc = priv;
+
+	if (rec->ar_startblock + rec->ar_blockcount <= rec->ar_startblock ||
+	    !xfs_verify_rtbno(sc->mp, rec->ar_startblock) ||
+	    !xfs_verify_rtbno(sc->mp, rec->ar_startblock +
+			rec->ar_blockcount - 1))
+		xfs_scrub_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
+	return 0;
+}
+
+/* Scrub the realtime bitmap. */
+int
+xfs_scrub_rtbitmap(
+	struct xfs_scrub_context	*sc)
+{
+	int				error;
+
+	error = xfs_rtalloc_query_all(sc->tp, xfs_scrub_rtbitmap_rec, sc);
+	if (!xfs_scrub_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
+		goto out;
+
+out:
+	return error;
+}
+
+/* Scrub the realtime summary. */
+int
+xfs_scrub_rtsummary(
+	struct xfs_scrub_context	*sc)
+{
+	/* XXX: implement this some day */
+	return -ENOENT;
+}

fs/xfs/scrub/scrub.c

@@ -247,6 +247,16 @@ static const struct xfs_scrub_meta_ops meta_scrub_ops[] = {
 		.setup	= xfs_scrub_setup_parent,
 		.scrub	= xfs_scrub_parent,
 	},
+	{ /* realtime bitmap */
+		.setup	= xfs_scrub_setup_rt,
+		.scrub	= xfs_scrub_rtbitmap,
+		.has	= xfs_sb_version_hasrealtime,
+	},
+	{ /* realtime summary */
+		.setup	= xfs_scrub_setup_rt,
+		.scrub	= xfs_scrub_rtsummary,
+		.has	= xfs_sb_version_hasrealtime,
+	},
 };
 
 /* This isn't a stable feature, warn once per day. */

fs/xfs/scrub/scrub.h

@@ -87,5 +87,20 @@ int xfs_scrub_directory(struct xfs_scrub_context *sc);
 int xfs_scrub_xattr(struct xfs_scrub_context *sc);
 int xfs_scrub_symlink(struct xfs_scrub_context *sc);
 int xfs_scrub_parent(struct xfs_scrub_context *sc);
+#ifdef CONFIG_XFS_RT
+int xfs_scrub_rtbitmap(struct xfs_scrub_context *sc);
+int xfs_scrub_rtsummary(struct xfs_scrub_context *sc);
+#else
+static inline int
+xfs_scrub_rtbitmap(struct xfs_scrub_context *sc)
+{
+	return -ENOENT;
+}
+static inline int
+xfs_scrub_rtsummary(struct xfs_scrub_context *sc)
+{
+	return -ENOENT;
+}
+#endif
 
 #endif	/* __XFS_SCRUB_SCRUB_H__ */