btrfs-progs: only report internal dev replace result if there's a result

If BTRFS_IOC_DEV_REPLACE ioctl failed, args.result usually won't be
updated by the ioctl.

And the arg has been initialized with 0, the result is always 0, which
is BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR, and the resulting error
message looks confusing:

ERROR: ioctl(DEV_REPLACE_START) failed on "/mnt/btrfs": No such file or directory, no error

But in case there's an internal result returned in future, don't drop
the result completely, instead print dev replace result message only
if the result is updated by a failed ioctl call.

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: code optimize cmd_scan_dev() use btrfs_register_one_device()

cmd_scan_dev() has it own code to register device (calling ioctl
BTRFS_IOC_SCAN_DEV), apparently it could use btrfs_register_one_device().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: check read extent errors when mapping

coverity barked out a warning that btrfs-map-logical was storing but
ignoring errors from read_extent_from_disk().   So don't ignore 'em.  I
made extent reading errors fatal to match the fatal errors from mapping
mirrors above.

And while we're at it have read_extent_from_disk() return -errno pread
errors instead of -EIO or -1 (-EPERM).  The only other caller who tests
errors clobbers them with -EIO.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: fix csum root copy-n-paste error

btrfs_setup_all_roots() had some copy and pasted code for trying to
setup a root and then creating a blank node if that failed.  The copy
for the csum_root created the blank node in the extent_root.

So we create a function to use a consistent root.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: Fix number of arguments check of 'btrfs fi df'

'btrfs fi df' needs exactly one arguments as mount option,
but as 3.17 we can run 'btrfs fi df' without any argument,
and it will error as "ERROR: can't access '%s'" which means
the argument number does not do what it should.

The bug is caused by manually modify the optind and use check_argc_max()
instead of the original check_argc_exact().

This patch fixes it by not modifying the optind and use check_argc_exact()
again.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
revert btrfs-progs: do a separate probe for _transient_ replacing device

There is a compatibility issue with older kernel with the progs commit id as below.

d0588bfa479409b2a0f6243f894338a01a56221a
btrfs-progs: do a separate probe for _transient_ replacing device

So as of now writing to revert the above commit id.
The brewing sysfs interface would help to fix the impending issue, which is
seed device would fail show in 'btrfs fi show' output of a sprout device.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: skip mounted fs when deal with umounted ones for fi show

Stalling problems may happen when exec balance & fi show cmds concurrently.

With the following commit:
        commit 915902c500
        btrfs-progs: fix device missing of btrfs fi show with seed devices

The fi show cmd will bother the mounted fs when only umounted fs should
be handled after @btrfs_can_kernel() has finished showing all mounted ones.

We could skip the mounted fs after @btrfs_can_kernel() is done, then tasks
keeps going on mounted fs while fi show continues on umounted ones separately.

Reported-by: Petr Janecek <janecek@ucw.cz>
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: Fix the argument requirement for '--subvol-extents'

The following commit changed the argument requirement for
'--subvol-extents', which causes it to call arg_strtou64() on NULL,
resulting a segfault.
d34cbe76 btrfs-progs: check: do not require argument for --subvol-extents

This patch revert the patch and change the help string and man page to
make it no longer confusing.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: fix linking with libbtrfs

Reported at https://github.com/openSUSE/snapper/issues/128

Commit cdb9e22e292275237c added another rbtree file that defines
functions that libbtrfs uses.

Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: introduce btrfs_register_all_device()

This function is to register all devices found after scanning
the system. Before we had this functionality with in the
btrfs_scan_lblkid(), however scanning and registering are two
different distinct operation its better keep them separate.
Also we want to optimize btrfs_scan_lblkid and avoid multiple
system scans unless needed. As of now device scan uses this function.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: optimize btrfs_scan_lblkid() for multiple calls

btrfs_scan_lblikd() is called by most the device related command functions.
And btrfs_scan_lblkid() is most expensive function and it becomes more expensive
as number of devices in the system increase. Further some threads call this
function more than once for absolutely no extra benefit and the real waste of
resources. Below list of threads and number of times btrfs_scan_lblkid()
is called in that thread.

  btrfs-find-root            1
  btrfs rescue super-recover 2
  btrfs-debug-tree           1
  btrfs-image -r             2
  btrfs check                2
  btrfs restore              2
  calc-size                  NC
  btrfs-corrupt-block        NC
  btrfs-image                NC
  btrfs-map-logical          1
  btrfs-select-super         NC
  btrfstune                  2
  btrfs-zero-log             NC
  tester                     NC
  quick-test.c               NC
  btrfs-convert              0
  mkfs                       #number of devices to be mkfs
  btrfs label set unmounted  2
  btrfs get label unmounted  2

This patch will:
  move out calling register_one_device with in btrfs_scan_lblkid()
  and so function setting the BTRFS_UPDATE_KERNEL to yes will
  call btrfs_register_all_devices() separately.

  introduce a global variable scan_done, which is set when scan is
  done succssfully per thread. So that following calls to this function
  will just return success.

  Further if any function needs to force scan after scan_done is set,
  then it can be done when there is such a requirement, but as of now there
  isn't any such requirement.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: libbtrfs, make exported headers compatible with C++

Add externs and don't use a reserved keyword.

Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs-progs: use the correct SI prefixes

The SI standard defines lowercase 'k' and uppercase for the rest.

Signed-off-by: David Sterba <dsterba@suse.cz>
Btrfs progs v3.17.1

Signed-off-by: David Sterba <dsterba@suse.cz>
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/btrfs-progs