btrfs-progs: use kernel for mounted disk for show

As of now btrfs filesystem show reads directly from
disks. So sometimes output can be stale, mainly when
user wants to cross verify their operation like,
label or device delete or add... etc. so this
patch will read from the kernel ioctl if it finds
that disk is mounted.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: use BTRFS_SCAN_LBLKID as default scan in filesystem show

btrfs progs has to scan for the btrfs disks for two main reasons,
 one to register them with the btrfs kernel (under btrfs dev scan)
 2nd to report btrfs disks to the user (under btrfs fi show)
 (there few more minor reasons like check_mounted etc..).

 To facilitate the scan, in total we have the following methods
 to scan for the btrfs

 BTRFS_SCAN_PROC
  which uses the /proc/partitions to look for the disks, when
  scanning it does it twice first would look for non dm- paths
  and in the 2nd scan it would pick only dm- paths.

 BTRFS_SCAN_DEV
  which scans all the block dev under /dev as they appear during
  scanning.

 BTRFS_SCAN_LBLKID
  this uses the library functions provided  by the lblkid to get
  only disks which contains the btrfs SB.

 The better method to use would be BTRFS_SCAN_LBLKID for the obvious
 reasons we don't have to reinvent that feature with in btrfs-progs.

 For the btrfs fi show - This patch will..
   - make BTRFS_SCAN_LBLKID as the default scan option

   (BTRFS_SCAN_DEV is accessible under the option --all-devices and
   BTRFS_SCAN_PROC won't be used by btrfs fi show any more)

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: device scan use BTRFS_SCAN_LBLKID by default

with this patch, BTRFS_SCAN_LBLKID (which leverages lblkid
to look for btrfs disks) would be the default scan method
to look for the btrfs disks. And thus the output as seen
in the latest btrfs fi show and btrfs fi show -m for the
mounted disks will have the consistent disks path.
(it was inconsistent (across disks) because btrfs dev scan
provided a different path from the mount command eg. below)

    devid    1 size 1.98GiB used 435.00MiB path /dev/mapper/mpatha
    devid    2 size 2.00GiB used 415.00MiB path /dev/dm-1

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: use the marco BTRFS_UPDATE_KERNEL where needed

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
mkfs: fix mkfs -r to properly allocate space

mkfs -r wasn't creating chunks properly, making it very difficult to
allocate space for anything except tiny filesystems.

This changes it around to use more of the generic infrastructure, and
to do actual logical->physical block number translation.

It also allocates space to the files in smaller extents (max 1MB), which
keeps the allocator from trying to allocate an extent bigger than a
single chunk.

It doesn't quite support multi-device mkfs -r yet, but is much closer.

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs-progs: make sure we return an error when we can't add a device

I noticed xfstests was failing in a weird way but it was because our device add
was failing but not actually returning an error so we were failing further down
the test.  Fix this by making sure we return an error if we fail the mkfs tests.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: make get_btrfs_mount callable

get_btrfs_mount is reusable function but it is printing
errors, this removes it. Here the parent function of
open_path_or_dev_mnt does print error msg on error.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: filesystem show of specified mounted disk should work

Originally, thinking was user will use mount point if the disk
is mounted. But thats not really true, actually user don't
(or shouldn't) care to check if disk mounted, so whether disk
is mounted/unmounted when disk path is specified it should work.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs-progs: make pretty_sizes take u64 instead of a double

This got changed to a double but all the callers still use a u64, which causes
us to segfault sometimes because of some weird C voodoo that I had to have
explained to me.  Apparently because we're using a double the compiler will use
the floating point registers to hold our argument which ends up not being
aligned properly if you don't actually give it a double so it will cause
problems for other things, in our case it was screwing up str_bytes so it was
larger than the actual size of the str.  This patch fixes the segfault.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs-progs: just return -ENOENT if we don't find the root item

We were bug_on(slot == 0), but that's just obnoxious, return -ENOENT so we can
handle the situation properly.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: add filter for deleted but uncleanded subvolumes

New option to subvolume list that acts as a global filter and applies
the other filters to either live subvolumes or the uncleaned ones.

The path to the deleted subvolumes is lost at the deletion time, sample
output looks like:

ID 259 gen 7 top level 0 path <FS_TREE>/DELETED

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
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>
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>
Btrfs-progs: set return value to 0 if subvolume get-default successfully

cmd_subvol_get_default() returns 1 even if finds default subvolume
successfully.

Set the correct return value.

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: fix potential double-frees in cmd_subvol_delete()

If we "goto again" in cmd_subvol_delete(), and error out to out:
before re-allocating the dupdname and dupvname pointers, we'll
double-free them.

Set them to NULL after freeing to avoid this.

Resolves-Coverity-CID: 1125944
Resolves-Coverity-CID: 1125945
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: fix error returns in get_df()

get_df returns -ERRNO, or maybe (+)errno, or even 0 in
the case where we inexplicably got 0 total_spaces from
the BTRFS_IOC_SPACE_INFO.

Consistently return a negative error number, and return
-ENOENT rather than 0 for total_spaces == 0, so that the
caller will know that **sargs_ret hasn't been set up.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: use strncpy in btrfs_scan_lblkid()

Use strncpy(... ,PATH_MAX) to be sure we don't overflow
the path[PATH_MAX] array.

Resolves-Coverity-CID: 1125941
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: fix test for return of realpath in find_mount_root()

find_mount_root() tries to test for realpath() failure, but
tests the wrong value.  Fix it.

Resolves-Coverity-CID: 1125940
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: don't leak fd in test_dev_for_mkfs() error paths

Close fd before we return on error paths.

Resolves-Coverity-CID: 1125939
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs-progs: fix leak of "buf" in make_btrfs() error paths

If any pwrite failed we leaked the allocated "buf" on
return from the function.  "goto out" takes care of
those paths.

Resolves-Coverity-CID: 1125938
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>