The exclusive ops will not start if there's one already running. Now
that we have the sysfs export (since kernel 5.10) to check if there's
one already running, use it to allow enqueueing of the operations as a
convenience.
Supported enqueuing:
btrfs balance start --enqueue
btrfs filesystem resize --enqueue
btrfs device add --enqueue
btrfs device delete --enqueue
btrfs replace start --enqueue
This patch implements the functionality based on Goldwyn's patch
https://lore.kernel.org/linux-btrfs/?q=20200825150338.32610-4-rgoldwyn%40suse.de
but on top of previous preparatory patches.
Note that 'filesystem resize' options could confuse getopt as the
negative size change looks like a series of short options and there's no
way to make getopt ignore the short options, so there's a custom option
parser.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
If the exclusive operation is available in sysfs file, check if there's
one already running. The check is done for:
- device add, remove, replace
- balance
- filesystem resize
All commands will validate arguments and check before the ioctl or
before any potentially irreversible operations (like clearing device
before replacing).
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
