btrfs-progs: do a separate probe for transient replacing device

As mentioned in the kernel patch

btrfs: ioctl BTRFS_IOC_FS_INFO and
 BTRFS_IOC_DEV_INFO miss-matched with slots

The count as returned by BTRFS_IOC_FS_INFO is the number of slots that
btrfs-progs would allocate for the BTRFS_IOC_DEV_INFO ioctl. Since
BTRFS_IOC_DEV_INFO would loop across the seed devices, So its better
ioctl BTRFS_IOC_FS_INFO returns the total_devices instead of num_devices.

The above mentioned patch just does that. That is, it returns
total_devices instead of num_devices.

Which means we need to probe for the replacing device separately.

This patch will probe for the replacing device separately.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Btrfs-progs: fsck: disallow partial opening if critical roots corrupted

If btrfs tree root is corrupted, fsck will hit the following segmentation.

enabling repair mode
Check tree block failed, want=29376512, have=0
Check tree block failed, want=29376512, have=0
Check tree block failed, want=29376512, have=0
Check tree block failed, want=29376512, have=0
Check tree block failed, want=29376512, have=0
read block failed check_tree_block
Couldn't read tree root
Checking filesystem on /dev/sda9
UUID: 0e1a754d-04a5-4256-ae79-0f769751803e
Critical roots corrupted, unable to fsck the FS
Segmentation fault (core dumped)

In btrfs_setup_all_roots(), we could tolerate some trees(extent tree, csum tree)
corrupted, and we have did careful check inside that function, it will
return NULL if critial roots corrupt(for example tree root).

The problem is that we check @OPEN_CTREE_PARTIAL flag again after
calling btrfs_setup_all_roots() which will successfully return
@fs_info though critial roots corrupted.

Fix this problem by removing @OPEN_CTREE_PARTIAL flag check outsize
btrfs_setup_all_roots().

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Btrfs-progs: fsck: only allow partial opening under repair mode

The reason that we allow partial opening is that sometimes,
we may have some corrupted trees.(for example extent tree), for
fsck repair case, the broken tree may be rebuilt later.

So if users only want to do check but not repair anything, this
patch will make fsck return failure as soon as possible and
tell users that some critial roots have been corrupted.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Btrfs-progs: fsck: deal with corrupted csum root

If checksum root is corrupted, fsck will get segmentation. This
is because if we fail to load checksum root, root's node is NULL which
cause NULL pointer deferences later.

To fix this problem, we just did something like extent tree rebuilding.
Allocate a new one and clear uptodate flag. We will do sanity check
before fsck going on.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: repair: remove recowed entry from the to-recow list

If we attempt to repair a filesystem with metadata blocks that need
recowing, we'll get into an infinite loop repeatedly recowing the
first entry in the list, without ever removing it from the list.
Oops.  Fixed.

Signed-off-by: Alexandre Oliva <oliva@gnu.org>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: check: do not dereference tree_refs as data_refs

In a filesystem corrupted by a faulty memory module, btrfsck would get
very confused attempting to access backrefs that weren't data backrefs
as if they were.  Besides invoking undefined behavior for accessing
potentially-uninitialized data past the end of objects, or with
dynamic types unrelated with the static types held in the
corresponding memory, it used offsets and lengths from such fields
that did not correspond to anything in the filesystem proper.

Moving the test for full backrefs and checking that they're data
backrefs earlier avoided the crash I was running into, but that was
not enough to make the filesystem complete a successful repair.

Signed-off-by: Alexandre Oliva <oliva@gnu.org>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: debug: print more info about inode

Add uid, gid, rdev and flags to btrfs_print_leaf.

Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: print B for bytes

This arguably helps parsers.

Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: extend pretty printers with unit mode

The functionality of pretty unit printing was duplicated by
df_pretty_sizes, merge it with pretty_size and enhance the interface
with more suffix mode. Raw, binary or decimal.

Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: Remove extra 'const' modifiers; they don't do anything.

'const int const *x' means the same thing as 'const int *x' or
'int const *x'; the intent was probably 'const int * const x'.
However, this won't work for the 'suffix' variable, as it has
to be assigned, and making the static tables into const pointers
to const chars leads to a mismatch there.

This was found with clang's duplicate-decl-specifier warning.

Signed-off-by: Adam Buchbinder <abuchbinder@google.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: add options to tune units for fi df output

The size unit format is a longstanding annoyance. This patch is based on
the work of Nils and Alexandre and enhances the options. It's possible
to select raw bytes, SI-based or IEC-based compact units (human
frientdly) or a fixed base from kilobytes to terabytes. The default is
compact human readable IEC-based, no change to current version.

CC: Nils Steinger <nst@voidptr.de>
CC: Alexandre Oliva <oliva@gnu.org>
Reviewed-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: convert: set label or copy from origin

Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: document the limit balance filter

Signed-off-by: David Sterba <dsterba@suse.cz>