On Wed, Nov 16, 2011 at 10:27 PM, Stefan Hajnoczi <stefa...@gmail.com> wrote: > On Wed, Nov 16, 2011 at 11:49 AM, Zhi Yong Wu <zwu.ker...@gmail.com> wrote: >> On Wed, Nov 16, 2011 at 6:34 PM, Stefan Hajnoczi <stefa...@gmail.com> wrote: >>> On Wed, Nov 16, 2011 at 6:57 AM, Chunyan Liu <cy...@suse.com> wrote: >>>> Currently qemu-nbd does not support finding free nbd device for users like >>>> "losetup -f" and issuing "qemu-nbd -c /dev/nbdX disk.img" won't report >>>> error >>>> message when /dev/nbd is already in use. It makes things a little >>>> confusing. >>>> This patch adds "-f" option to qemu-nbd to support finding a free nbd >>>> device >>>> for users. Please review and share your comments. Thanks. >>>> >>>> Signed-off-by: Chunyan Liu <cy...@suse.com> >>>> --- >>>> qemu-nbd.c | 65 >>>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++- >>>> 1 files changed, 64 insertions(+), 1 deletions(-) >>> >>> This patch finds a free device but does not immediately attach to it >>> and use it. Interfaces like this are prone to race conditions, I >>> think it would make more sense to combine the -f option with running >>> the actual NBD server. >>> >>> I suggest: >>> qemu-nbd -f disk.img >> Why must we add one new option? I prefer to not adding new option, >> only enhance existing function of qemu-nbd -c disk.img. > > That would change the command-line interface and break existing users. > There might be scripts or tools that call out to qemu-nbd, they would > break if we changed the meaning of -c. Sound reasonable, thanks > > Stefan >
-- Regards, Zhi Yong Wu
