qemu-img: mandate argument to 'qemu-img check --repair'

qemu-img check --repair option accepts an argument. The argument to
--repair switch can either be 'all' or 'leak'. Fix the long option to
mandate argument with --repair switch.

The patch fixes following segmentation fault

Core was generated by `qemu-img check -f qcow2 --repair all t.qcow2'.
Program terminated with signal 11, Segmentation fault.
0  in img_check (argc=6, argv=0x7fffab9b8a10) at qemu-img.c:588
588	            if (!strcmp(optarg, "leaks")) {
(gdb) bt
  0  img_check (argc=6, argv=0x7fffab9b8a10) at qemu-img.c:588
  1  __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6
  2  _start ()
(gdb)

Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
Reviewed-by: Leandro Dorileo <l@dorileo.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Fixed various typos

Signed-off-by: Deepak Kathayat <deepak.mk17@gmail.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
mirror: fix throttling delay calculation

The throttling delay calculation was using an inaccurate sector count to
calculate the time to sleep.  This broke rate-limiting for the block
mirror job.

Move the delay calculation into mirror_iteration() where we know how
many sectors were transferred.  This lets us calculate an accurate delay
time.

Reported-by: Joaquim Barrera <jbarrera@ac.upc.edu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
mirror: fix early wake from sleep due to aio

The mirror blockjob coroutine rate-limits itself by sleeping.  The
coroutine also performs I/O asynchronously so it's important that the
aio callback doesn't wake the coroutine early as that breaks
rate-limiting.

Reported-by: Joaquim Barrera <jbarrera@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>