There was a discussion about possibility of using
superblock backup for creating images with e2image.
https://www.spinics.net/lists/linux-ext4/msg30583.html
Now our customer faced with situation then it would be
useful to have image file from partition with broken
superblock.
Here is set of patches that adds this functionality.
This is third version of the patch set. Changes since v2:
* Moved ext2fs_try_open_fs() deletions
* automatically try to open the backup superblocks
* Options are sorted in alphabetical order
* run_e2fsck is used for test
* manual is added into the patch that adds this option
Artem Blagodarenko (4):
ext2fs: opening filesystem code refactoring
e2image: add -b option to use supperblock backup
tests: add test for e2image -b option
ext2fs: automaticlly open backup superblocks
e2fsck/e2fsck.h | 2 -
e2fsck/message.c | 3 +-
e2fsck/unix.c | 44 +++++--------
e2fsck/util.c | 73 ---------------------
lib/ext2fs/ext2fs.h | 8 +++
lib/ext2fs/openfs.c | 152 +++++++++++++++++++++++++++++++++++++++++++-
misc/dumpe2fs.c | 17 +----
misc/e2image.8.in | 32 ++++++++++
misc/e2image.c | 50 +++++++++++++--
tests/i_zero_super/expect.1 | 22 +++++++
tests/i_zero_super/image.gz | Bin 0 -> 13262 bytes
tests/i_zero_super/script | 11 ++++
12 files changed, 288 insertions(+), 126 deletions(-)
create mode 100644 tests/i_zero_super/expect.1
create mode 100644 tests/i_zero_super/image.gz
create mode 100644 tests/i_zero_super/script
--
2.13.6 (Apple Git-96)
From: Artem Blagodarenko <[email protected]>
There are similar opening filesystem code in different utilities.
The patch moves this code to ext2fs_try_open_fs().
This function make one of the action based on parameters:
1) open filesystem with given superblock, superblock size
2) open filesystem with given superblock, but try to
find right block size
3) open filesystem with default superblock and block size
Signed-off-by: Artem Blagodarenko <[email protected]>
---
e2fsck/unix.c | 28 +++-------------------------
lib/ext2fs/openfs.c | 36 +++++++++++++++++++++++++++++++++++-
misc/dumpe2fs.c | 17 +++--------------
3 files changed, 41 insertions(+), 40 deletions(-)
diff --git a/e2fsck/unix.c b/e2fsck/unix.c
index b46dcb2d..2865f37a 100644
--- a/e2fsck/unix.c
+++ b/e2fsck/unix.c
@@ -1134,31 +1134,9 @@ static errcode_t try_open_fs(e2fsck_t ctx, int flags, io_manager io_ptr,
ext2_filsys *ret_fs)
{
errcode_t retval;
-
- *ret_fs = NULL;
- if (ctx->superblock && ctx->blocksize) {
- retval = ext2fs_open2(ctx->filesystem_name, ctx->io_options,
- flags, ctx->superblock, ctx->blocksize,
- io_ptr, ret_fs);
- } else if (ctx->superblock) {
- int blocksize;
- for (blocksize = EXT2_MIN_BLOCK_SIZE;
- blocksize <= EXT2_MAX_BLOCK_SIZE; blocksize *= 2) {
- if (*ret_fs) {
- ext2fs_free(*ret_fs);
- *ret_fs = NULL;
- }
- retval = ext2fs_open2(ctx->filesystem_name,
- ctx->io_options, flags,
- ctx->superblock, blocksize,
- io_ptr, ret_fs);
- if (!retval)
- break;
- }
- } else
- retval = ext2fs_open2(ctx->filesystem_name, ctx->io_options,
- flags, 0, 0, io_ptr, ret_fs);
-
+ retval = ext2fs_open2(ctx->filesystem_name, ctx->io_options,
+ flags, ctx->superblock, ctx->blocksize,
+ io_ptr, ret_fs);
if (retval == 0) {
(*ret_fs)->priv_data = ctx;
e2fsck_set_bitmap_type(*ret_fs, EXT2FS_BMAP64_RBTREE,
diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
index f74cd245..585ad766 100644
--- a/lib/ext2fs/openfs.c
+++ b/lib/ext2fs/openfs.c
@@ -108,7 +108,7 @@ errcode_t ext2fs_open(const char *name, int flags, int superblock,
* EXT2_FLAG_64BITS - Allow 64-bit bitfields (needed for large
* filesystems)
*/
-errcode_t ext2fs_open2(const char *name, const char *io_options,
+static errcode_t __ext2fs_open2(const char *name, const char *io_options,
int flags, int superblock,
unsigned int block_size, io_manager manager,
ext2_filsys *ret_fs)
@@ -497,6 +497,40 @@ cleanup:
return retval;
}
+errcode_t ext2fs_open2(const char *name, const char *io_options,
+ int flags, int superblock,
+ unsigned int block_size, io_manager manager,
+ ext2_filsys *ret_fs)
+{
+ errcode_t retval;
+
+ *ret_fs = NULL;
+ if (superblock && block_size) {
+ retval = __ext2fs_open2(name, io_options,
+ flags, superblock, block_size,
+ manager, ret_fs);
+ } else if (superblock) {
+ int block_size;
+
+ for (block_size = EXT2_MIN_BLOCK_SIZE;
+ block_size <= EXT2_MAX_BLOCK_SIZE; block_size *= 2) {
+ if (*ret_fs) {
+ ext2fs_free(*ret_fs);
+ *ret_fs = NULL;
+ }
+ retval = __ext2fs_open2(name,
+ io_options, flags,
+ superblock, block_size,
+ manager, ret_fs);
+ if (!retval)
+ break;
+ }
+ } else
+ retval = __ext2fs_open2(name, io_options,
+ flags, 0, 0, manager, ret_fs);
+ return retval;
+}
+
/*
* Set/get the filesystem data I/O channel.
*
diff --git a/misc/dumpe2fs.c b/misc/dumpe2fs.c
index 395ea9ee..6c4d7965 100644
--- a/misc/dumpe2fs.c
+++ b/misc/dumpe2fs.c
@@ -568,20 +568,9 @@ int main (int argc, char ** argv)
if (image_dump)
flags |= EXT2_FLAG_IMAGE_FILE;
try_open_again:
- if (use_superblock && !use_blocksize) {
- for (use_blocksize = EXT2_MIN_BLOCK_SIZE;
- use_blocksize <= EXT2_MAX_BLOCK_SIZE;
- use_blocksize *= 2) {
- retval = ext2fs_open (device_name, flags,
- use_superblock,
- use_blocksize, unix_io_manager,
- &fs);
- if (!retval)
- break;
- }
- } else
- retval = ext2fs_open (device_name, flags, use_superblock,
- use_blocksize, unix_io_manager, &fs);
+ retval = ext2fs_open2(device_name, 0,
+ flags, use_superblock, use_blocksize,
+ unix_io_manager, &fs);
if (retval && !(flags & EXT2_FLAG_IGNORE_CSUM_ERRORS)) {
flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
goto try_open_again;
--
2.13.6 (Apple Git-96)
From: Artem Blagodarenko <[email protected]>
e2image has no ability to use superblock backup to copy metadata.
This feature can be useful if someone wants to make partition
image and fix it using e2fsck utility.
New -b option allows to pass superblock number, like e2fsck utility do.
e2image doesn't change primary superblock and store is as is, so
it can be fixed using e2fsck latter.
Signed-off-by: Artem Blagodarenko <[email protected]>
---
misc/e2image.8.in | 32 ++++++++++++++++++++++++++++++++
misc/e2image.c | 44 ++++++++++++++++++++++++++++++++++++++------
2 files changed, 70 insertions(+), 6 deletions(-)
diff --git a/misc/e2image.8.in b/misc/e2image.8.in
index f28a76ea..d6125bb4 100644
--- a/misc/e2image.8.in
+++ b/misc/e2image.8.in
@@ -11,6 +11,14 @@ e2image \- Save critical ext2/ext3/ext4 filesystem metadata to a file
.B \-r|Q
]
[
+.B \-b
+.I superblock
+]
+[
+.B \-B
+.I blocksize
+]
+[
.B \-fr
]
.I device
@@ -167,6 +175,22 @@ the
option will prevent analysis of problems related to hash-tree indexed
directories.
.PP
+Option
+.B \-b
+.I superblock
+can be used to get image from partition with broken primary superblock.
+The partition is copied as is including broken primary superblock.
+.PP
+Option
+.B \-B
+.I blocksize
+can be used to set superblock block size. Normally, e2fsck will search
+for the superblock at various different block sizes in an attempt to find
+the appropriate blocksize. This search can be fooled in some cases. This
+option forces e2fsck to only try locating the superblock at a particular
+blocksize. If the superblock is not found, e2fsck will terminate with a
+fatal error.
+.PP
Note that this will work even if you substitute "/dev/hda1" for another raw
disk image, or QCOW2 image previously created by
.BR e2image .
@@ -217,6 +241,14 @@ This can be useful to write a qcow2 image containing all data to a
sparse image file where it can be loop mounted, or to a disk partition.
Note that this may not work with qcow2 images not generated by e2image.
.PP
+Options
+.B \-b
+.I superblock
+and
+.B \-B
+.I blocksize
+can be used same way as for raw images.
+.PP
.SH INCLUDING DATA
Normally
.B e2image
diff --git a/misc/e2image.c b/misc/e2image.c
index be001f0f..b1b7a17d 100644
--- a/misc/e2image.c
+++ b/misc/e2image.c
@@ -104,7 +104,8 @@ static int get_bits_from_size(size_t size)
static void usage(void)
{
- fprintf(stderr, _("Usage: %s [ -r|Q ] [ -fr ] device image-file\n"),
+ fprintf(stderr, _("Usage: %s [ -r|Q ] [ -b superblock ] [ -B blocksize]"
+ "[ -fr ] device image-file\n"),
program_name);
fprintf(stderr, _(" %s -I device image-file\n"), program_name);
fprintf(stderr, _(" %s -ra [ -cfnp ] [ -o src_offset ] "
@@ -1256,7 +1257,8 @@ static void output_qcow2_meta_data_blocks(ext2_filsys fs, int fd)
free_qcow2_image(img);
}
-static void write_raw_image_file(ext2_filsys fs, int fd, int type, int flags)
+static void write_raw_image_file(ext2_filsys fs, int fd, int type, int flags,
+ blk64_t superblock)
{
struct process_block_struct pb;
struct ext2_inode inode;
@@ -1284,6 +1286,22 @@ static void write_raw_image_file(ext2_filsys fs, int fd, int type, int flags)
}
}
+ if (superblock) {
+ int j;
+
+ ext2fs_mark_block_bitmap2(meta_block_map, superblock);
+ meta_blocks_count++;
+
+ /*
+ * Mark the backup superblock descriptors
+ */
+ for (j = 0; j < fs->desc_blocks; j++) {
+ ext2fs_mark_block_bitmap2(meta_block_map,
+ ext2fs_descriptor_block_loc2(fs, superblock, j));
+ }
+ meta_blocks_count += fs->desc_blocks;
+ }
+
mark_table_blocks(fs);
if (show_progress)
fprintf(stderr, "%s", _("Scanning inodes...\n"));
@@ -1463,6 +1481,8 @@ int main (int argc, char ** argv)
int ignore_rw_mount = 0;
int check = 0;
struct stat st;
+ blk64_t superblock = 0;
+ int blocksize = 0;
#ifdef ENABLE_NLS
setlocale(LC_MESSAGES, "");
@@ -1476,8 +1496,14 @@ int main (int argc, char ** argv)
if (argc && *argv)
program_name = *argv;
add_error_table(&et_ext2_error_table);
- while ((c = getopt(argc, argv, "nrsIQafo:O:pc")) != EOF)
+ while ((c = getopt(argc, argv, "b:B:nrsIQafo:O:pc")) != EOF)
switch (c) {
+ case 'b':
+ superblock = strtoull(optarg, NULL, 0);
+ break;
+ case 'B':
+ blocksize = strtoul(optarg, NULL, 0);
+ break;
case 'I':
flags |= E2IMAGE_INSTALL_FLAG;
break;
@@ -1529,6 +1555,11 @@ int main (int argc, char ** argv)
"with raw or QCOW2 images."));
exit(1);
}
+ if (superblock && !img_type) {
+ com_err(program_name, 0, "%s", _("-b option can only be used "
+ "with raw or QCOW2 images."));
+ exit(1);
+ }
if ((source_offset || dest_offset) && img_type != E2IMAGE_RAW) {
com_err(program_name, 0, "%s",
_("Offsets are only allowed with raw images."));
@@ -1579,8 +1610,9 @@ int main (int argc, char ** argv)
}
}
sprintf(offset_opt, "offset=%llu", source_offset);
- retval = ext2fs_open2(device_name, offset_opt, open_flag, 0, 0,
- unix_io_manager, &fs);
+ retval = ext2fs_open2(device_name, offset_opt, open_flag,
+ superblock, blocksize, unix_io_manager,
+ &fs);
if (retval) {
com_err (program_name, retval, _("while trying to open %s"),
device_name);
@@ -1665,7 +1697,7 @@ skip_device:
exit(1);
}
if (img_type)
- write_raw_image_file(fs, fd, img_type, flags);
+ write_raw_image_file(fs, fd, img_type, flags, superblock);
else
write_image_file(fs, fd);
--
2.13.6 (Apple Git-96)
From: Artem Blagodarenko <[email protected]>
The test makes raw image from partition with broken super block
and executes e2fsck.
Signed-off-by: Artem Blagodarenko <[email protected]>
---
tests/i_zero_super/expect.1 | 22 ++++++++++++++++++++++
tests/i_zero_super/image.gz | Bin 0 -> 13262 bytes
tests/i_zero_super/script | 11 +++++++++++
3 files changed, 33 insertions(+)
diff --git a/tests/i_zero_super/expect.1 b/tests/i_zero_super/expect.1
new file mode 100644
index 00000000..fda32b96
--- /dev/null
+++ b/tests/i_zero_super/expect.1
@@ -0,0 +1,22 @@
+Pass 1: Checking inodes, blocks, and sizes
+Pass 2: Checking directory structure
+Pass 3: Checking directory connectivity
+Pass 4: Checking reference counts
+Pass 5: Checking group summary information
+Free blocks count wrong for group #0 (7987, counted=7982).
+Fix? no
+
+Free blocks count wrong (11602, counted=11597).
+Fix? no
+
+Free inodes count wrong for group #0 (1493, counted=1488).
+Fix? no
+
+Free inodes count wrong (2997, counted=2992).
+Fix? no
+
+
+test_filesys: ********** WARNING: Filesystem still has errors **********
+
+test_filesys: 11/3008 files (0.0% non-contiguous), 398/12000 blocks
+Exit status is 4
diff --git a/tests/i_zero_super/image.gz b/tests/i_zero_super/image.gz
new file mode 100644
index 0000000000000000000000000000000000000000..eea9140194f4dd9ec9dc8bb7b9e2215b950587d2
GIT binary patch
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diff --git a/tests/i_zero_super/script b/tests/i_zero_super/script
new file mode 100644
index 00000000..6b02d86d
--- /dev/null
+++ b/tests/i_zero_super/script
@@ -0,0 +1,11 @@
+if test -x $E2IMAGE_EXE; then
+
+ONE_PASS_ONLY=true
+FSCK_OPT="-n -b 8193 -f"
+PREP_CMD="$E2IMAGE_EXE -r -b 8193 -B 1024 $TMPFILE $TMPFILE.raw; \
+ mv $TMPFILE.raw $TMPFILE"
+. $cmd_dir/run_e2fsck
+
+else
+ echo "$test_name: $test_description: skipped"
+fi
--
2.13.6 (Apple Git-96)
e2image and e2fsck automatically try to open some backup superblocks,
if only blocksize is set or passed superblock can't be opened.
Try few backup superblocks (e.g. {1, 3, 5,7, 9} * blocksize * 8).
This code is moved to library.
Signed-off-by: Artem Blagodarenko <[email protected]>
---
e2fsck/e2fsck.h | 2 -
e2fsck/message.c | 3 +-
e2fsck/unix.c | 16 ++++++--
e2fsck/util.c | 73 ---------------------------------
lib/ext2fs/ext2fs.h | 8 ++++
lib/ext2fs/openfs.c | 116 ++++++++++++++++++++++++++++++++++++++++++++++++++++
misc/e2image.c | 10 ++++-
7 files changed, 146 insertions(+), 82 deletions(-)
diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
index 9eee4bc2..9cd3910e 100644
--- a/e2fsck/e2fsck.h
+++ b/e2fsck/e2fsck.h
@@ -634,8 +634,6 @@ extern void e2fsck_write_inode_full(e2fsck_t ctx, unsigned long ino,
#ifdef MTRACE
extern void mtrace_print(char *mesg);
#endif
-extern blk64_t get_backup_sb(e2fsck_t ctx, ext2_filsys fs,
- const char *name, io_manager manager);
extern int ext2_file_type(unsigned int mode);
extern int write_all(int fd, char *buf, size_t count);
void dump_mmp_msg(struct mmp_struct *mmp, const char *msg);
diff --git a/e2fsck/message.c b/e2fsck/message.c
index 727f71d5..df408917 100644
--- a/e2fsck/message.c
+++ b/e2fsck/message.c
@@ -465,7 +465,8 @@ static _INLINE_ void expand_percent_expression(FILE *f, ext2_filsys fs,
fprintf(f, "%*lld", width, (long long) ctx->blkcount);
break;
case 'S':
- fprintf(f, "%llu", get_backup_sb(NULL, fs, NULL, NULL));
+ fprintf(f, "%llu", ext2fs_first_backup_sb(NULL, NULL, fs,
+ NULL, NULL));
break;
case 's':
fprintf(f, "%*s", width, ctx->str ? ctx->str : "NULL");
diff --git a/e2fsck/unix.c b/e2fsck/unix.c
index 2865f37a..888a2fce 100644
--- a/e2fsck/unix.c
+++ b/e2fsck/unix.c
@@ -1471,11 +1471,19 @@ restart:
retval ? _("Superblock invalid,") :
_("Group descriptors look bad..."));
orig_superblock = ctx->superblock;
- get_backup_sb(ctx, fs, ctx->filesystem_name, io_ptr);
- if (fs)
- ext2fs_close_free(&fs);
orig_retval = retval;
- retval = try_open_fs(ctx, flags, io_ptr, &fs);
+ retval = ext2fs_try_backups(ctx->filesystem_name,
+ ctx->io_options,
+ flags,
+ &ctx->superblock,
+ &ctx->blocksize, io_ptr,
+ &fs);
+ if (retval == 0) {
+ fs->priv_data = ctx;
+ e2fsck_set_bitmap_type(fs,
+ EXT2FS_BMAP64_RBTREE,
+ "default", NULL);
+ }
if ((orig_retval == 0) && retval != 0) {
if (fs)
ext2fs_close_free(&fs);
diff --git a/e2fsck/util.c b/e2fsck/util.c
index ed947025..b1c638c5 100644
--- a/e2fsck/util.c
+++ b/e2fsck/util.c
@@ -548,79 +548,6 @@ void mtrace_print(char *mesg)
}
#endif
-blk64_t get_backup_sb(e2fsck_t ctx, ext2_filsys fs, const char *name,
- io_manager manager)
-{
- struct ext2_super_block *sb;
- io_channel io = NULL;
- void *buf = NULL;
- int blocksize;
- blk64_t superblock, ret_sb = 8193;
-
- if (fs && fs->super) {
- ret_sb = (fs->super->s_blocks_per_group +
- fs->super->s_first_data_block);
- if (ctx) {
- ctx->superblock = ret_sb;
- ctx->blocksize = fs->blocksize;
- }
- return ret_sb;
- }
-
- if (ctx) {
- if (ctx->blocksize) {
- ret_sb = ctx->blocksize * 8;
- if (ctx->blocksize == 1024)
- ret_sb++;
- ctx->superblock = ret_sb;
- return ret_sb;
- }
- ctx->superblock = ret_sb;
- ctx->blocksize = 1024;
- }
-
- if (!name || !manager)
- goto cleanup;
-
- if (manager->open(name, 0, &io) != 0)
- goto cleanup;
-
- if (ext2fs_get_mem(SUPERBLOCK_SIZE, &buf))
- goto cleanup;
- sb = (struct ext2_super_block *) buf;
-
- for (blocksize = EXT2_MIN_BLOCK_SIZE;
- blocksize <= EXT2_MAX_BLOCK_SIZE ; blocksize *= 2) {
- superblock = blocksize*8;
- if (blocksize == 1024)
- superblock++;
- io_channel_set_blksize(io, blocksize);
- if (io_channel_read_blk64(io, superblock,
- -SUPERBLOCK_SIZE, buf))
- continue;
-#ifdef WORDS_BIGENDIAN
- if (sb->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
- ext2fs_swap_super(sb);
-#endif
- if ((sb->s_magic == EXT2_SUPER_MAGIC) &&
- (EXT2_BLOCK_SIZE(sb) == blocksize)) {
- ret_sb = superblock;
- if (ctx) {
- ctx->superblock = superblock;
- ctx->blocksize = blocksize;
- }
- break;
- }
- }
-
-cleanup:
- if (io)
- io_channel_close(io);
- if (buf)
- ext2fs_free_mem(&buf);
- return (ret_sb);
-}
-
/*
* Given a mode, return the ext2 file type
*/
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 6774e32c..942b46ea 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -1584,6 +1584,14 @@ extern int ext2fs_journal_sb_start(int blocksize);
extern errcode_t ext2fs_open(const char *name, int flags, int superblock,
unsigned int block_size, io_manager manager,
ext2_filsys *ret_fs);
+extern blk64_t ext2fs_first_backup_sb(blk64_t *superblock,
+ unsigned int *blocksize,
+ ext2_filsys fs, const char *name,
+ io_manager manager);
+extern errcode_t ext2fs_try_backups(const char *name, const char *io_options,
+ int flags, blk64_t *superblock,
+ unsigned int *block_size,
+ io_manager manager, ext2_filsys *ret_fs);
extern errcode_t ext2fs_open2(const char *name, const char *io_options,
int flags, int superblock,
unsigned int block_size, io_manager manager,
diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
index 585ad766..d0e1d3bd 100644
--- a/lib/ext2fs/openfs.c
+++ b/lib/ext2fs/openfs.c
@@ -497,6 +497,122 @@ cleanup:
return retval;
}
+blk64_t ext2fs_first_backup_sb(blk64_t *superblock, unsigned int *block_size,
+ ext2_filsys fs, const char *name,
+ io_manager manager)
+{
+ struct ext2_super_block *sb;
+ io_channel io = NULL;
+ void *buf = NULL;
+ int try_blocksize;
+ blk64_t try_superblock, ret_sb = 8193;
+
+ if (fs && fs->super) {
+ ret_sb = (fs->super->s_blocks_per_group +
+ fs->super->s_first_data_block);
+ *superblock = ret_sb;
+ *block_size = fs->blocksize;
+ return ret_sb;
+ }
+
+ if (*block_size) {
+ ret_sb = *block_size * 8;
+ if (*block_size == 1024)
+ ret_sb++;
+ *superblock = ret_sb;
+ return ret_sb;
+ }
+
+ *superblock = ret_sb;
+ *block_size = 1024;
+
+ if (!name || !manager)
+ goto cleanup;
+
+ if (manager->open(name, 0, &io) != 0)
+ goto cleanup;
+
+ if (ext2fs_get_mem(SUPERBLOCK_SIZE, &buf))
+ goto cleanup;
+ sb = (struct ext2_super_block *) buf;
+
+ for (try_blocksize = EXT2_MIN_BLOCK_SIZE;
+ try_blocksize <= EXT2_MAX_BLOCK_SIZE ; try_blocksize *= 2) {
+ try_superblock = try_blocksize*8;
+ if (try_blocksize == 1024)
+ try_superblock++;
+ io_channel_set_blksize(io, try_blocksize);
+ if (io_channel_read_blk64(io, try_superblock,
+ -SUPERBLOCK_SIZE, buf))
+ continue;
+#ifdef WORDS_BIGENDIAN
+ if (sb->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
+ ext2fs_swap_super(sb);
+#endif
+ if ((sb->s_magic == EXT2_SUPER_MAGIC) &&
+ (EXT2_BLOCK_SIZE(sb) == try_blocksize)) {
+ ret_sb = try_superblock;
+ *superblock = try_superblock;
+ *block_size = try_blocksize;
+ break;
+ }
+ }
+
+cleanup:
+ if (io)
+ io_channel_close(io);
+ if (buf)
+ ext2fs_free_mem(&buf);
+ return ret_sb;
+}
+
+errcode_t ext2fs_try_backups(const char *name, const char *io_options,
+ int flags, blk64_t *superblock,
+ unsigned int *block_size, io_manager manager,
+ ext2_filsys *ret_fs)
+{
+ errcode_t retval;
+ blk64_t try_block_number;
+ unsigned int i;
+
+ /*
+ * Get first superblock location based on heuristic.
+ * Blocksize is also returned and used to find next
+ * superblock copy location.
+ */
+ try_block_number = ext2fs_first_backup_sb(superblock, block_size,
+ *ret_fs, name, manager);
+ retval = ext2fs_open2(name,
+ io_options, flags,
+ try_block_number, *block_size,
+ manager, ret_fs);
+ if (!retval)
+ return 0;
+
+ /*
+ * Trt 3d, 5th, 7th, 9th superblock copy
+ */
+ for (i = 3; i <= 9; i += 2) {
+ try_block_number = (i * (*block_size) * 8);
+ if (*block_size == 1024)
+ try_block_number++;
+ if (*ret_fs) {
+ ext2fs_free(*ret_fs);
+ *ret_fs = NULL;
+ }
+ retval = ext2fs_open2(name,
+ io_options, flags,
+ try_block_number, *block_size,
+ manager, ret_fs);
+ if (!retval) {
+ *superblock = try_block_number;
+ break;
+ }
+ }
+
+ return retval;
+}
+
errcode_t ext2fs_open2(const char *name, const char *io_options,
int flags, int superblock,
unsigned int block_size, io_manager manager,
diff --git a/misc/e2image.c b/misc/e2image.c
index b1b7a17d..069768e1 100644
--- a/misc/e2image.c
+++ b/misc/e2image.c
@@ -1611,8 +1611,14 @@ int main (int argc, char ** argv)
}
sprintf(offset_opt, "offset=%llu", source_offset);
retval = ext2fs_open2(device_name, offset_opt, open_flag,
- superblock, blocksize, unix_io_manager,
- &fs);
+ superblock, blocksize, unix_io_manager, &fs);
+ if (retval & (superblock | blocksize)) {
+ printf(_("Try backups in other location.\n"));
+ retval = ext2fs_try_backups(device_name, offset_opt, open_flag,
+ &superblock, &blocksize,
+ unix_io_manager, &fs);
+ printf(_("Use superblock %i.\n"), superblock);
+ }
if (retval) {
com_err (program_name, retval, _("while trying to open %s"),
device_name);
--
2.13.6 (Apple Git-96)
Hello Theodore,
Do I need to update something in this patch?
Thanks,
Artem Blagodarenko.