Introduce a new 'fsmap' command to the fs debugger that will query the
rmap btree to report the file/metadata extents mapped to a range of
physical blocks.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
db/Makefile | 2 -
db/command.c | 2 +
db/fsmap.c | 163 +++++++++++++++++++++++++++++++++++++++++++++++++++++
db/fsmap.h | 20 +++++++
man/man8/xfs_db.8 | 9 +++
5 files changed, 195 insertions(+), 1 deletion(-)
create mode 100644 db/fsmap.c
create mode 100644 db/fsmap.h
diff --git a/db/Makefile b/db/Makefile
index 8260da3..5adea48 100644
--- a/db/Makefile
+++ b/db/Makefile
@@ -12,7 +12,7 @@ HFILES = addr.h agf.h agfl.h agi.h attr.h attrshort.h bit.h
block.h bmap.h \
dir2.h dir2sf.h dquot.h echo.h faddr.h field.h \
flist.h fprint.h frag.h freesp.h hash.h help.h init.h inode.h input.h \
io.h logformat.h malloc.h metadump.h output.h print.h quit.h sb.h \
- sig.h strvec.h text.h type.h write.h attrset.h symlink.h
+ sig.h strvec.h text.h type.h write.h attrset.h symlink.h fsmap.h
CFILES = $(HFILES:.h=.c)
LSRCFILES = xfs_admin.sh xfs_ncheck.sh xfs_metadump.sh
diff --git a/db/command.c b/db/command.c
index 3c17a1e..278c357 100644
--- a/db/command.c
+++ b/db/command.c
@@ -49,6 +49,7 @@
#include "write.h"
#include "malloc.h"
#include "dquot.h"
+#include "fsmap.h"
cmdinfo_t *cmdtab;
int ncmds;
@@ -128,6 +129,7 @@ init_commands(void)
echo_init();
frag_init();
freesp_init();
+ fsmap_init();
help_init();
hash_init();
inode_init();
diff --git a/db/fsmap.c b/db/fsmap.c
new file mode 100644
index 0000000..a9de401
--- /dev/null
+++ b/db/fsmap.c
@@ -0,0 +1,163 @@
+/*
+ * Copyright (C) 2016 Oracle. All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
+ *
+ * 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 "libxfs.h"
+#include "command.h"
+#include "fsmap.h"
+#include "output.h"
+#include "init.h"
+
+struct fsmap_info {
+ unsigned long long nr;
+ xfs_agnumber_t agno;
+};
+
+static int
+fsmap_fn(
+ struct xfs_btree_cur *cur,
+ struct xfs_rmap_irec *rec,
+ void *priv)
+{
+ struct fsmap_info *info = priv;
+
+ dbprintf(_("%llu: %u/%u len %u owner %lld offset %llu bmbt %d attrfork
%d extflag %d\n"),
+ info->nr, info->agno, rec->rm_startblock,
+ rec->rm_blockcount, rec->rm_owner, rec->rm_offset,
+ !!(rec->rm_flags & XFS_RMAP_BMBT_BLOCK),
+ !!(rec->rm_flags & XFS_RMAP_ATTR_FORK),
+ !!(rec->rm_flags & XFS_RMAP_UNWRITTEN));
+ info->nr++;
+
+ return 0;
+}
+
+int
+fsmap_f(
+ int argc,
+ char **argv)
+{
+ char *p;
+ struct fsmap_info info;
+ xfs_agnumber_t start_ag;
+ xfs_agnumber_t end_ag;
+ xfs_agnumber_t agno;
+ xfs_fsblock_t start_fsb = 0;
+ xfs_fsblock_t end_fsb = NULLFSBLOCK;
+ struct xfs_rmap_irec low;
+ struct xfs_rmap_irec high;
+ struct xfs_btree_cur *bt_cur;
+ struct xfs_buf *agbp;
+ int c;
+ xfs_daddr_t eofs;
+ int error;
+
+ if (!xfs_sb_version_hasrmapbt(&mp->m_sb)) {
+ dbprintf(_("Filesystem does not support reverse mapping
btree.\n"));
+ return 0;
+ }
+
+ while ((c = getopt(argc, argv, "")) != EOF) {
+ switch (c) {
+ default:
+ dbprintf(_("Bad option for fsmap command.\n"));
+ return 0;
+ }
+ }
+
+ if (argc > optind) {
+ start_fsb = strtoull(argv[optind], &p, 0);
+ if (*p != '\0' || start_fsb >= mp->m_sb.sb_dblocks) {
+ dbprintf(_("Bad fsmap start_fsb %s.\n"), argv[optind]);
+ return 0;
+ }
+ }
+
+ if (argc > optind + 1) {
+ end_fsb = strtoull(argv[optind + 1], &p, 0);
+ if (*p != '\0') {
+ dbprintf(_("Bad fsmap end_fsb %s.\n"), argv[optind +
1]);
+ return 0;
+ }
+ }
+
+ eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
+ if (XFS_FSB_TO_DADDR(mp, end_fsb) >= eofs)
+ end_fsb = XFS_DADDR_TO_FSB(mp, eofs - 1);
+
+ low.rm_startblock = XFS_FSB_TO_AGBNO(mp, start_fsb);
+ low.rm_owner = 0;
+ low.rm_offset = 0;
+ low.rm_flags = 0;
+ high.rm_startblock = -1U;
+ high.rm_owner = ULLONG_MAX;
+ high.rm_offset = ULLONG_MAX;
+ high.rm_flags = XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK |
XFS_RMAP_UNWRITTEN;
+
+ start_ag = XFS_FSB_TO_AGNO(mp, start_fsb);
+ end_ag = XFS_FSB_TO_AGNO(mp, end_fsb);
+
+ info.nr = 0;
+ for (agno = start_ag; agno <= end_ag; agno++) {
+ if (agno == end_ag)
+ high.rm_startblock = XFS_FSB_TO_AGBNO(mp, end_fsb);
+
+ error = xfs_alloc_read_agf(mp, NULL, agno, 0, &agbp);
+ if (error) {
+ dbprintf(_("Error %d while reading AGF.\n"), error);
+ return 0;
+ }
+
+ bt_cur = xfs_rmapbt_init_cursor(mp, NULL, agbp, agno);
+ if (!bt_cur) {
+ libxfs_putbuf(agbp);
+ dbprintf(_("Not enough memory.\n"));
+ return 0;
+ }
+
+ info.agno = agno;
+ error = xfs_rmapbt_query_range(bt_cur, &low, &high,
+ fsmap_fn, &info);
+ if (error) {
+ xfs_btree_del_cursor(bt_cur, XFS_BTREE_ERROR);
+ libxfs_putbuf(agbp);
+ dbprintf(_("Error %d while querying fsmap btree.\n"),
+ error);
+ return 0;
+ }
+
+ xfs_btree_del_cursor(bt_cur, XFS_BTREE_NOERROR);
+ libxfs_putbuf(agbp);
+
+ if (agno == start_ag)
+ low.rm_startblock = 0;
+ }
+
+ return 0;
+}
+
+static const cmdinfo_t fsmap_cmd =
+ { "fsmap", NULL, fsmap_f, 0, 2, 0,
+ N_("start_fsb [end_fsb]"),
+ N_("display reverse mapping(s)"), NULL };
+
+void
+fsmap_init(void)
+{
+ add_command(&fsmap_cmd);
+}
diff --git a/db/fsmap.h b/db/fsmap.h
new file mode 100644
index 0000000..f8aacd3
--- /dev/null
+++ b/db/fsmap.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2016 Oracle. All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
+ *
+ * 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.
+ */
+extern void fsmap_init(void);
diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8
index b6d2f64..514e3aa 100644
--- a/man/man8/xfs_db.8
+++ b/man/man8/xfs_db.8
@@ -568,6 +568,15 @@ command to convert to and from this form. Block numbers
given for file blocks
.B bmap
command) are in this form.
.TP
+.BI "fsmap [ " start " ] [ " end " ]
+Prints the mapping of disk blocks used by an XFS filesystem. The map
+lists each extent used by files, allocation group metadata,
+journalling logs, and static filesystem metadata, as well as any
+regions that are unused. All blocks, offsets, and lengths are specified
+in units of 512-byte blocks, no matter what the filesystem's block size is.
+.BI "The optional " start " and " end " arguments can be used to constrain
+the output to a particular range of disk blocks.
+.TP
.BI hash " string
Prints the hash value of
.I string
|