Commit Graph

75 Commits

Author SHA1 Message Date
David Sterba bea9ba0acb btrfs-progs: restore: add more long option variants
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-05-14 15:41:06 +02:00
David Sterba 18b48340de btrfs-progs: restore: shift option texts
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-05-14 15:41:06 +02:00
David Sterba ffd53c0fe8 btrfs-progs: restore: use bigger buffer for output path name
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-05-14 15:41:06 +02:00
Dan Merillat bd91f80725 btrfs-progs: optionally restore symlinks.
Restore symlinks, optionally with owner/times.

Signed-off-by: Dan Merillat <dan.merillat@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-05-14 15:41:02 +02:00
Dan Merillat 829950844e btrfs-progs: restore: separate the overwrite check
Symlink restore needs this, but the cut&paste became too complicated.
Simplify everything.

Signed-off-by: Dan Merillat <dan.merillat@gmail.com>
[message wording adjustments]
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-29 17:55:18 +02:00
David Sterba 630a917aa1 btrfs-progs: restore: don't misreport errors from search_dir
The logic around return value has changed in the metadata restore
patches. The return value from btrfs_search_slot may remain non-zero and
is returned. This is incorrectly interpreted as an error.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-29 16:48:04 +02:00
David Sterba 582e156baf btrfs-progs: fix typos in restore help/doc
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-24 17:28:37 +02:00
David Sterba faf8b94323 btrfs-progs: restore: cleanup, use PATH_MAX
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-24 15:42:05 +02:00
David Sterba 9ea0eff31f btrfs-progs: restore: convert copy_file exit paths to a single return
Resolves-coverity-id: 1295365
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-24 15:42:05 +02:00
David Sterba 97f8e20930 btrfs-progs: restore: convert search_dir exit paths to a single return
Resolves-coverity-id: 1295366
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-24 15:42:05 +02:00
David Sterba a8762e43fd btrfs-progs: restore: fix path leak in copy_metadata
The path lifecycle spans only this function and we have to free it.

Resolves-coverity-id: 1295367
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-24 15:42:05 +02:00
Dan Merillat 7732e6ef62 btrfs-progs: restore: optionally restore metadata
As long as the inode is intact, the file metadata can be restored.
Directory data is restored at the end of search_dir.  Errors are
checked and returned, unless ignore_errors is requested.

Signed-off-by: Dan Merillat <dan.merillat@gmail.com>
[minor style fixes, error message updates]
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-24 15:42:04 +02:00
David Sterba 08f9acadab btrfs-progs: getopt, use symbolic name for argument requirements
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-08 17:39:51 +02:00
David Sterba 4074ae5f2b btrfs-progs: cleanup option index argument from getopt_long
We're not using it anywhere. The best practice is to add enums with
values > 255 for the long options, option index counting is error prone.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-04-08 17:33:55 +02:00
Gui Hecheng f18f8b7afc btrfs-progs: restore, fix page alignment issue for lzo compression
When runing restore under lzo compression, "bad compress length"
problems are encountered.
It is because there is a page alignment problem with the @decompress_lzo,
as follows:
		|------| |----|-| |------|...|------|
		  page         ^    page       page
			       |
			  3 bytes left

When lzo pages are compressed in memory, we will ensure that the 4 bytes
length header will not cross a page boundary.  There is a situation that
3 (or less) bytes are left at the end of a page, and then the 4 bytes
len is stored at the start of the next page.  But the @decompress_lzo
doesn't go to the start of the next page and continue to read the next 4
bytes which crosses two pages, so a random value is fetched as a "bad
compress length".

So we check page alignment every time before we are going to fetch the
next @len and after the former piece of data is decompressed.  If the
current page that we reach has less than 4 bytes left, then we should
fetch the next @len at the start of next page.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
[simplifed and moved into decompress_lzo]
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-03-23 23:43:49 +01:00
Qu Wenruo ccdd0a067f btrfs-progs: read_tree_block() and read_node_slot() cleanup.
Allow read_tree_block() and read_node_slot() to return error pointer.
This should help caller to get more specified error number.

For existing callers, change (!eb) judgmentt to
(!extent_buffer_uptodate(eb)) to keep the compatibility, and for caller
missing the check, use PTR_ERR(eb) if possible.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-02-02 19:21:24 +01:00
Karel Zak 33f2d6b84d btrfs-progs: autoconf: use standard PACKAGE_* macros
- use standard PACKAGE_{NAME,VERSION,STRING,URL,...} autoconf macros
  rather than homemade BTRFS_BUILD_VERSION

- don't #include version.h, now the file is necessary for library API only

Note that "btrfs version" returns "btrfs-progs <version>" instead of
the original confusing "btrfs <version>".

Signed-off-by: Karel Zak <kzak@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-01-28 18:00:58 +01:00
Dimitri John Ledkov e69e015634 btrfs-progs: drop feature defines from C files, in favour of CFLAGS defines
glibc 2.10+ (5+ years old) enables all the desired features:
_XOPEN_SOURCE 700, __XOPEN2K8, POSIX_C_SOURCE, DEFAULT_SOURCE; with a
single _GNU_SOURCE define in the makefile alone. For portability to
other libc implementations (e.g. dietlibc) _XOPEN_SOURCE=700 is also
defined.

This also resolves Debian bug report filed by Michael Tautschnig -
"Inconsistent use of _XOPEN_SOURCE results in conflicting
declarations". Whilst I was not able to reproduce the results, the
reported fact is that _XOPEN_SOURCE set to 500 in one set of files
(e.g. cmds-filesystem.c) generates/defines different struct stat from
other files (cmds-replace.c).

This patch thus cleans up all feature defines, and sets them at a
consistent level.

Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=747969
Signed-off-by: Dimitri John Ledkov <dimitri.j.ledkov@intel.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-01-27 14:45:59 +01:00
David Sterba 2b7cdab425 btrfs-progs: make getopt tables static const
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-01-19 13:44:49 +01:00
David Sterba ecbf1339a6 btrfs-progs: cleanup, move getop long options close to their use
Move long_option defintions just before getopt_long everywhere.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-01-19 13:30:06 +01:00
Gui Hecheng 103f68d715 btrfs-progs: cleanup duplicate assignment of variable leaf for btrfs-restore
The value of variable leaf in while loop don't have to be set
for every round. Just move it outside.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-12-04 18:51:51 +01:00
Christian Hesse 5bfc3fea81 btrfs-progs: fix compiler warning
gcc 4.9.0 gives a warning: array subscript is above array bounds

Checking for "greater or equal" instead of just "equal" fixes this.

The warning is a false positive, appears with -ftree-vrp, but we'd
rather fix it to avoid noise during build.

http://www.mail-archive.com/linux-btrfs%40vger.kernel.org/msg34338.html

Signed-off-by: Christian Hesse <mail@eworm.de>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-11-18 18:25:58 +01:00
Josef Bacik 6d6a3e7991 Btrfs-progs: spit out the broken file when ignoring errors
It's nice to ignore errors on restore, but spit out the filename so the user
knows which files of his aren't going to look right.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-11-14 11:00:24 +01:00
Gui Hecheng d2a97ca131 btrfs-progs: remove wrong set_argv0 for restore
Before this patch, you could see the following after exec restore
	# :too few arguments

The tool name "btrfs restore" is missing.

The @set_argv0() function is introduced by:
	commit a184abc70f
	btrfs-progs: move the check_argc_* functions into utils.c
	...
	Also add a new function "set_argv0" to set the correct tool name:
        *btrfs-image*: too few arguments

But @set_argv0() only applies to the independent tools with
the name pattern btrfs-***.
Since restore is now is subcommand under "btrfs",
there is no need to use @set_argv0() before check_argc_* to
repair the prompt tool name before "too few arguments".

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-09-14 19:06:12 +02:00
Gui Hecheng 24f5a651d9 btrfs-progs: fix next_leaf in restore as it improperly skips some slots
When entering the next level node, the @next_leaf in restore forgets to
start at the first slot. Just reset it to the first one.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-09-14 14:50:54 +02:00
Gui Hecheng c7d16e08bd btrfs-progs: fix len of read_extent_buffer for inline extent in restore
Steps to reproduce:
	# mkfs.btrfs -f <dev>
	# mount -o compress-force=lzo <dev> <mnt>
	# for ((i=0;i<4000;i++)); do
	  	echo -n 'A' >> <mnt>/inline_data
	  done
	# umount <mnt>
	# valgrind --tool=memcheck --leak-check=full	\
	  btrfs restore <dev> <dest_dir>
output:
	==32118== Invalid read of size 1
	==32118==    at 0x4A0A4E4: memcpy@@GLIBC_2.14
	==32118==    by 0x43DC91: read_extent_buffer
	==32118==    by 0x421401: search_dir (cmds-restore.c:240)
	==32118==    by 0x422CBB: cmd_restore (cmds-restore.c:1317)
	==32118==    by 0x404709: main (btrfs.c:248)
	==32118==  Address 0x4c4f4ac is not stack'd, malloc'd or...

It is because when deal with inline extent, the read_extent_buffer
is now reading a len of @ram_bytes which is the len of the uncompressed
data. But actually here we want the len of the inline item.
So in the compressed situation, use the len of the inline item.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-09-14 14:49:00 +02:00
Gui Hecheng 2527730d5d btrfs-progs: init uninitialized output buf for btrfs-restore
A memory problem reported by valgrind as follows:
	=== Syscall param pwrite64(buf) points to uninitialised byte(s)
When running:
	# valgrind --leak-check=yes btrfs restore /dev/sda9 /mnt/backup

Because the output buf size is alloced with malloc, but the length of
output data is shorter than the sizeof(buf), so valgrind report
uninitialised byte(s).
We could use calloc to repalce malloc and clear this WARNING away.

Reported-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-09-14 13:10:44 +02:00
Gui Hecheng 101a8e1326 btrfs-progs: move debug info to verbose mode for restore
The restore tool should only print info of the restoring process
in verbose mode with -v option specified.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-09-02 17:05:07 +02:00
Gui Hecheng 5f1313a45d btrfs-progs: remove unused flags for btrfs_path
The three flags of @btrfs_path:
	btrfs_path {
		unsigned int keep_locks:1;
		unsigned int skip_locking:1;
		unsigned int leave_spinning:1;
	}
have little meaning, because the userspace @btrfs_search_slot()
is free of locking and no other routines will decide their behavior
on these. So just remove them.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-28 02:03:18 +02:00
Justin Maggard 2ac5cdf79f btrfs-progs: add always option to restore's looping prompt
If you are using btrfs restore to try to recover a very large or
fragmented file, you may encounter _lots_ of prompts requiring
you to press 'y' to continue because we are looping a lot.

Add the option to press 'a', to supress these prompts for the rest
of the file.

Signed-off-by: Justin Maggard <jmaggard10@gmail.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 15:07:03 +02:00
Wang Shilong 84ebfa6d88 Btrfs-progs: fix some build warnings on 32bit platform
Fix following build warnings on 32bit platform:

...
utils.c:1708:3: warning: left shift count >= width of
type [enabled by default]
   if (x << i & (1UL << 63))
   ^
qgroup-verify.c:393:9: warning: cast to pointer from integer
of different size [-Wint-to-pointer-cast]
  return (struct tree_block *)unode->aux;
         ^
qgroup-verify.c:407:38: warning: cast from pointer to integer
of different size [-Wpointer-to-int-cast]
   if (ulist_add(tree_blocks, bytenr, (unsigned long long)block, 0) >= 0)
                                      ^
cmds-restore.c:120:4: warning: format %lu expects argument of type
long unsigned int, but argument 3 has type size_t [-Wformat=]
    fprintf(stderr, "bad compress length %lu\n", in_len);
...

BTW, this patch also switches other castings with new helpers.

Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 15:07:03 +02:00
Gui Hecheng f1672e50c7 btrfs-progs: use check_argc_* to check arg number for all tools
Since this patch:
	btrfs-progs: move the check_argc_* functions into utils.c

All tools including the independent tools(e.g. btrfs-image, btrfs-convert)
can share the convenience of the check_argc_* functions, so this patch
adopt the argc check functions globally.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 15:07:02 +02:00
Wang Shilong c24c92f4ae btrfs-progs: restore: document updates
Add some missing options, also improve some confusing
expressions.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 14:43:10 +02:00
Wang Shilong 958bd97a55 btrfs-progs: restore: don't allow users to specify -r and -f at the same time
These two options are used for same purpose, but they are exclusive with
each other. Make it clear to common users.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 14:43:10 +02:00
Wang Shilong 4cb5168ba6 btrfs-progs: restore: output resason why it fails to read root
Previously if restore could not read users specified fs root, it would
output following message:

 Error reading root

With this patch, it will output message like:

 Fail to read root 1000: No such file or directory

Signed-off-byr Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 14:43:10 +02:00
Wang Shilong c2059f765d btrfs-progs: restore: fix wrong return value if it fails to read specified fs root
Steps to reproduce:
 # mkfs.btrfs -f /dev/sda9
 # btrfs restore -f 1 -o /tmp /dev/sda9
 # echo $?

Fix to return 1 in this failure path.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 14:43:09 +02:00
Wang Shilong d46111425a btrfs-progs: restore: check if specified root is fs/file tree firstly
Steps to reproduce:
 # mkfs.btrfs -f /dev/sda9
 # mount /dev/sda9 /mnt
 # dd if=/dev/zero of=/mnt/data bs=1M count=1
 # btrfs restore -r /dev/sda9 -r 2 -o /tmp

If users don't input a valid fs/file root objectid, btrfs restore still
continue and don't restore anything, this is unfriendly, we could
check it firstly.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 14:43:09 +02:00
Vincent Stehlé 93ebec96f2 btrfs-progs: restore: check lzo compress length
When things go wrong for lzo-compressed btrfs, feeding lzo1x_decompress_safe()
with corrupt data during restore can lead to crashes. Reduce the risk by adding
a check on the input length.

Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 14:43:09 +02:00
Filipe David Borba Manana c17d0a73c1 Btrfs-progs: update btrfs_file_extent_inline_len to match kernel version
The following kernel commit changed the definition of the inline function
btrfs_file_extent_inline_len():

    commit 514ac8ad8793a097c0c9d89202c642479d6dfa34
    Author: Chris Mason <clm@fb.com>
    Date:   Fri Jan 3 21:07:00 2014 -0800

    Btrfs: don't use ram_bytes for uncompressed inline items

    If we truncate an uncompressed inline item, ram_bytes isn't updated to reflect
    the new size.  The fixe uses the size directly from the item header when
    reading uncompressed inlines, and also fixes truncate to update the
    size as it goes.

Not having this new definition implies that the restore tool might misbehave when
restoring files with an inline extent that got truncated on a kernel older than
release 3.14.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-04-11 19:47:29 +02:00
Filipe David Borba Manana d2334781fd Btrfs-progs: restore, for compressed extents don't read more bytes than needed
We need to read a number of bytes corresponding to the disk size of the file extent
item, and not to the number of bytes in the num_bytes field. Normally disk_size is
smaller than num_bytes (when using compression), except for files created with lzo
compression in a kernel older then the one which introduced the following change:

commit 59516f6017c589e7316418fda6128ba8f829a77f
Author: Stefan Agner <stefan@agner.ch>
Date:   Mon Jul 1 20:33:39 2013 +0200

    Btrfs: return -1 when lzo compression makes data bigger

    With this fix the lzo code behaves like the zlib code by returning an
    error
    code when compression does not help reduce the size of the file.
    This is currently not a bug since the compressed size is checked again
    in
    the calling method compress_file_range.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-04-11 19:40:35 +02:00
Christophe Vu-Brugier b5fe148715 btrfs-progs: include <sys/xattr.h> instead of <attr/xattr.h>
The `btrfs` and `mkfs.btrfs` binaries are not linked against libattr
so the correct header to include is <sys/xattr.h>.

This fixes the build when attr header files are not installed.

Signed-off-by: Christophe Vu-Brugier <cvubrugier@yahoo.fr>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 06:23:31 -07:00
Filipe David Borba Manana 4314116bae Btrfs-progs: fix restore of files with compressed extents
The code was incorrectly adding the file extent items' data offset to the logical
disk address of the extent (bytenr) when the extent is compressed. The offset is
relative to the uncompressed data and not to what we store on disk (compressed).
Also it attempted to copy ram_bytes to destination, which is incorrect when the
data offset field is non-zero, it must use num_bytes instead.

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 06:23:28 -07:00
Wang Shilong aab2f48c18 Btrfs-progs: switch to arg_strtou64() part1
switch to arg_strtou64 plus some cleanups to remove unnecessary
codes.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 06:23:19 -07:00
Justin Maggard 2a7f8cf9ee btrfs-progs: add dry-run option to restore command
Sometimes it is useful to see what btrfs restore is going to do
before provisioning enough external storage to restore onto.
Add a dry-run option so we can see what files and paths are found
by restore, without actually restoring any data.

Signed-off-by: Justin Maggard <jmaggard10@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 06:23:16 -07:00
Josef Bacik 4735d0bb82 Btrfs-progs: rework open_ctree to take flags, add a new one V2
So I needed to add a flag to not try to read block groups when doing
--init-extent-tree since we could hang there, but that meant adding a whole
other 0/1 type flag to open_ctree_fs_info.  So instead I've converted it all
over to using a flags setting and added the flag that I needed.  This has been
tested with xfstests and make test.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-07 16:10:40 -05:00
Josef Bacik 337f86fea1 Btrfs-progs: add -b to btrfsck to look at backup roots
In some cases the tree root is so hosed we can't get anything useful out of it.
So add the -b option to btrfsck to make us look for the most recent backup tree
root to use for repair.  Then we can hopefully get ourselves into a working
state.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-07 13:29:30 -05:00
Ross Kirk af86684e9b btrfs-progs: drop unused parameter from btrfs_item_nr
Remove unused eb parameter from btrfs_item_nr, unused since introduced
in 7777e63b42

Signed-off-by: Ross Kirk <ross.kirk@gmail.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-10-16 08:23:10 -04:00
Wang Shilong d9f612220f Btrfs-progs: fix magic return value in cmds-restore.c
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-10-16 08:20:41 -04:00
Filipe David Borba Manana 1bef332a03 Btrfs-progs: fix restore command leaving corrupted files
When there are files that have parts shared with snapshots, the
restore command was incorrectly restoring them, as it was not
taking into account the offset and number of bytes fields from
the file extent item. Besides leaving the recovered file corrupt,
it was also inneficient as it read and wrote more data than needed
(with each extent copy overwriting portions of the one previously
written).

The following steps show how to reproduce this corruption issue:

$ mkfs.btrfs -f  /dev/sdb3
$ mount /dev/sdb3 /mnt/btrfs
$ perl -e '$d = "\x41" . ("\x00" x (1024*1024+349)); open($f,">","/mnt/btrfs/foobar"); print $f $d; close($f);'
$ du -b /mnt/btrfs/foobar
1048926 /mnt/btrfs/foobar
$ md5sum /mnt/btrfs/foobar
f9f778f3a7410c40e4ed104a3a63c3c4  /mnt/btrfs/foobar

$ btrfs subvolume snapshot /mnt/btrfs /mnt/btrfs/my_snap
$ perl -e 'open($f, "+<", "/mnt/btrfs/foobar"); seek($f, 4096, 0); print $f "\xff"; close($f);'
$ md5sum /mnt/btrfs/foobar
b983fcefd4622a03a78936484c40272b  /mnt/btrfs/foobar
$ umount /mnt/btrfs

$ btrfs restore /dev/sdb3 /tmp/copy
$ du -b /tmp/copy/foobar
1048926 /tmp/copy/foobar
$ md5sum /tmp/copy/foobar
88db338cbc1c44dfabae083f1ce642d5  /tmp/copy/foobar
$ od -t x1 -j 8192 -N 4 /tmp/copy/foobar
0020000 41 00 00 00
0020004
$ mount /dev/sdb3 /mnt/btrfs
$ od -t x1 -j 8192 -N 4 /mnt/btrfs/foobar
0020000 00 00 00 00
0020004
$ md5sum /mnt/btrfs/foobar
b983fcefd4622a03a78936484c40272b  /mnt/btrfs/foobar

Tested this change with zlib, lzo compression and file sizes larger
than 1GiB, and found no regression or other corruption issues (so far
at least).

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-10-16 08:20:03 -04:00
Zach Brown c17a056f38 btrfs-progs: use NULL instead of 0
These were mostly in option structs but there were a few gross string
pointer arguments given as 0.

Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-03 19:41:11 +02:00