[PATCH 2/2] xfs_repair: new secondary superblock search method
Bill O'Donnell
billodo at redhat.com
Tue Feb 9 11:13:08 CST 2016
Optimize secondary sb search, using similar method to find
fs geometry as that of xfs_mkfs. If this faster method fails
in finding a secondary sb, fall back to original brute force
slower search.
Signed-off-by: Bill O'Donnell <billodo at redhat.com>
---
Makefile | 2 +-
include/libxcmd.h | 4 +++-
libxcmd/topology.c | 28 +++++++++++++++++++++++++++-
repair/Makefile | 4 ++--
repair/phase1.c | 25 +++++++++++++++++++++++--
repair/protos.h | 2 +-
repair/sb.c | 27 +++++++++++++++++++++------
7 files changed, 78 insertions(+), 14 deletions(-)
diff --git a/Makefile b/Makefile
index fca0a42..1d60d9c 100644
--- a/Makefile
+++ b/Makefile
@@ -80,7 +80,7 @@ fsr: libhandle
growfs: libxcmd
io: libxcmd libhandle
quota: libxcmd
-repair: libxlog
+repair: libxlog libxcmd
copy: libxlog
ifeq ($(HAVE_BUILDDEFS), yes)
diff --git a/include/libxcmd.h b/include/libxcmd.h
index df7046e..b140adb 100644
--- a/include/libxcmd.h
+++ b/include/libxcmd.h
@@ -50,6 +50,8 @@ extern int
check_overwrite(
char *device);
-
+extern int guess_default_geometry(__uint64_t *agsize,
+ __uint64_t *agcount,
+ libxfs_init_t x);
#endif /* __LIBXCMD_H__ */
diff --git a/libxcmd/topology.c b/libxcmd/topology.c
index 0eeea28..4a8ab8b 100644
--- a/libxcmd/topology.c
+++ b/libxcmd/topology.c
@@ -302,7 +302,6 @@ static void blkid_get_topology(
#endif /* ENABLE_BLKID */
-
void get_topology(
libxfs_init_t *xi,
struct fs_topology *ft,
@@ -346,3 +345,30 @@ void get_topology(
&lsectorsize, &psectorsize, force_overwrite);
}
}
+
+/*
+ * Use this macro before we have superblock and mount structure
+ */
+#define DTOBT(d) ((xfs_rfsblock_t)((d) >> (blocklog - BBSHIFT)))
+
+int guess_default_geometry(__uint64_t *agsize, __uint64_t *agcount, libxfs_init_t x) {
+ struct fs_topology ft;
+ int blocklog;
+ __uint64_t dblocks;
+ int multidisk;
+ memset(&ft, 0, sizeof(ft));
+ get_topology(&x, &ft, 1);
+
+ /*
+ * get geometry from get_topology result.
+ * Use default block size (2^12)
+ */
+ blocklog = 12;
+ multidisk = ft.dswidth | ft.dsunit;
+ printf("x.dsize = %lu\n",(long unsigned int)x.dsize);
+ dblocks = DTOBT(x.dsize);
+ calc_default_ag_geometry(blocklog, dblocks, multidisk,
+ agsize, agcount);
+
+ return(blocklog);
+}
diff --git a/repair/Makefile b/repair/Makefile
index 251722b..d24ab1f 100644
--- a/repair/Makefile
+++ b/repair/Makefile
@@ -20,8 +20,8 @@ CFILES = agheader.c attr_repair.c avl.c avl64.c bmap.c btree.c \
progress.c prefetch.c rt.c sb.c scan.c threads.c \
versions.c xfs_repair.c
-LLDLIBS = $(LIBXFS) $(LIBXLOG) $(LIBUUID) $(LIBRT) $(LIBPTHREAD)
-LTDEPENDENCIES = $(LIBXFS) $(LIBXLOG)
+LLDLIBS = $(LIBBLKID) $(LIBXFS) $(LIBXLOG) $(LIBUUID) $(LIBRT) $(LIBPTHREAD) $(LIBXCMD)
+LTDEPENDENCIES = $(LIBXFS) $(LIBXLOG) $(LIBXCMD)
LLDFLAGS = -static-libtool-libs
default: depend $(LTCOMMAND)
diff --git a/repair/phase1.c b/repair/phase1.c
index 126d0b3..c27033d 100644
--- a/repair/phase1.c
+++ b/repair/phase1.c
@@ -21,6 +21,7 @@
#include "agheader.h"
#include "protos.h"
#include "err_protos.h"
+#include "libxcmd.h"
static void
no_sb(void)
@@ -47,6 +48,9 @@ alloc_ag_buf(int size)
*/
#define MAX_SECTSIZE (512 * 1024)
+extern libxfs_init_t x;
+
+
/* ARGSUSED */
void
phase1(xfs_mount_t *mp)
@@ -54,6 +58,10 @@ phase1(xfs_mount_t *mp)
xfs_sb_t *sb;
char *ag_bp;
int rval;
+ int blocklog;
+ __uint64_t agcount;
+ __uint64_t agsize;
+ __uint64_t skipsize;
do_log(_("Phase 1 - find and verify superblock...\n"));
@@ -65,6 +73,18 @@ phase1(xfs_mount_t *mp)
lost_quotas = 0;
/*
+ * divine the geometry ;)
+ */
+ blocklog = guess_default_geometry(&agsize, &agcount, x);
+
+ /*
+ * use found ag geometry to quickly find secondary sb
+ */
+ skipsize = agsize << blocklog;
+ do_log("agsize = %d agcount = %d skipsize = %d\n",
+ (int)agsize, (int)agcount, (int)skipsize);
+
+ /*
* get AG 0 into ag header buf
*/
ag_bp = alloc_ag_buf(MAX_SECTSIZE);
@@ -80,14 +100,15 @@ phase1(xfs_mount_t *mp)
if (rval != XR_OK) {
do_warn(_("bad primary superblock - %s !!!\n"),
err_string(rval));
- if (!find_secondary_sb(sb))
+
+ if (!find_secondary_sb(sb, skipsize))
no_sb();
primary_sb_modified = 1;
} else if ((rval = verify_set_primary_sb(sb, 0,
&primary_sb_modified)) != XR_OK) {
do_warn(_("couldn't verify primary superblock - %s !!!\n"),
err_string(rval));
- if (!find_secondary_sb(sb))
+ if (!find_secondary_sb(sb, skipsize))
no_sb();
primary_sb_modified = 1;
}
diff --git a/repair/protos.h b/repair/protos.h
index 9d5a2a6..d96373e 100644
--- a/repair/protos.h
+++ b/repair/protos.h
@@ -31,7 +31,7 @@ int get_sb(xfs_sb_t *sbp,
void write_primary_sb(xfs_sb_t *sbp,
int size);
-int find_secondary_sb(xfs_sb_t *sb);
+int find_secondary_sb(xfs_sb_t *sb, __uint64_t skipsize);
struct fs_geometry;
void get_sb_geometry(struct fs_geometry *geo,
diff --git a/repair/sb.c b/repair/sb.c
index 4eef14a..4386479 100644
--- a/repair/sb.c
+++ b/repair/sb.c
@@ -87,8 +87,7 @@ copy_sb(xfs_sb_t *source, xfs_sb_t *dest)
/*
* find a secondary superblock, copy it into the sb buffer
*/
-int
-find_secondary_sb(xfs_sb_t *rsb)
+static int __find_secondary_sb(xfs_sb_t *rsb, __uint64_t skipsize )
{
xfs_off_t off;
xfs_sb_t *sb;
@@ -101,7 +100,6 @@ find_secondary_sb(xfs_sb_t *rsb)
int bsize;
do_warn(_("\nattempting to find secondary superblock...\n"));
-
sb = (xfs_sb_t *)memalign(libxfs_device_alignment(), BSIZE);
if (!sb) {
do_error(
@@ -117,7 +115,7 @@ find_secondary_sb(xfs_sb_t *rsb)
/*
* skip first sector since we know that's bad
*/
- for (done = 0, off = XFS_AG_MIN_BYTES; !done ; off += bsize) {
+ for (done = 0, off = skipsize; !done ; off += bsize) {
/*
* read disk 1 MByte at a time.
*/
@@ -130,7 +128,6 @@ find_secondary_sb(xfs_sb_t *rsb)
}
do_warn(".");
-
/*
* check the buffer 512 bytes at a time since
* we don't know how big the sectors really are.
@@ -164,11 +161,29 @@ find_secondary_sb(xfs_sb_t *rsb)
}
}
}
-
free(sb);
return(retval);
}
+int
+find_secondary_sb(xfs_sb_t *rsb, __uint64_t skipsize)
+{
+ int retval;
+
+ /*
+ * Attempt to find secondary sb with a coarse approach,
+ * using a large skipsize (agsize in bytes). Failing that,
+ * fallback to the fine-grained approach using min agsize.
+ */
+ retval = __find_secondary_sb(rsb, skipsize);
+ if (!retval)
+ /*
+ * fallback: use minimum agsize for skipsize
+ */
+ retval = __find_secondary_sb(rsb, XFS_AG_MIN_BYTES);
+ return(retval);
+}
+
/*
* Calculate what the inode alignment field ought to be based on internal
* superblock info and determine if it is valid.
--
2.5.0
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