Re: [Qemu-devel] [PATCH] block/mirror: enable detect zeroes when driving mirror

[wyang <w90p710@gmail.com>]

On 2016年11月21日 14:51, Vasiliy Tolstov wrote:
>
> 21 Ноя 2016 г. 4:27 пользователь "Yang Wei" <w90p710@gmail.com 
> <mailto:w90p710@gmail.com>> написал:
> >
> > In order to preserve sparse disk image, detect_zeroes
> > should also be enabled when bdrv_get_block_status_above()
> > returns BDRV_BLOCK_DATA
> >
> > Signed-off-by: Yang Wei <w90p710@gmail.com <mailto:w90p710@gmail.com>>
> > ---
>
> Hi, does this patch fixes bug 
> https://bugzilla.redhat.com/show_bug.cgi?id=1219541 ? Or it unrelated 
> to this issue?
>
yes, you also need to  backport  the functionality of NBD's write 
zeroes(  fa778f and 1f4d6d)

Thanks
Wei
>
>
> >  block/mirror.c | 7 +++++++
> >  1 file changed, 7 insertions(+)
> >
> > diff --git a/block/mirror.c b/block/mirror.c
> > index b2c1fb8..8b20b7a 100644
> > --- a/block/mirror.c
> > +++ b/block/mirror.c
> > @@ -76,6 +76,7 @@ typedef struct MirrorOp {
> >      QEMUIOVector qiov;
> >      int64_t sector_num;
> >      int nb_sectors;
> > +    BlockdevDetectZeroesOptions backup_detect_zeroes;
> >  } MirrorOp;
> >
> >  static BlockErrorAction mirror_error_action(MirrorBlockJob *s, bool 
> read,
> > @@ -132,6 +133,8 @@ static void mirror_write_complete(void *opaque, 
> int ret)
> >  {
> >      MirrorOp *op = opaque;
> >      MirrorBlockJob *s = op->s;
> > +    BlockDriverState *target = s->target;
> > +    target->detect_zeroes = op->backup_detect_zeroes;
> >      if (ret < 0) {
> >          BlockErrorAction action;
> >
> > @@ -148,6 +151,7 @@ static void mirror_read_complete(void *opaque, 
> int ret)
> >  {
> >      MirrorOp *op = opaque;
> >      MirrorBlockJob *s = op->s;
> > +    BlockDriverState *target = s->target;
> >      if (ret < 0) {
> >          BlockErrorAction action;
> >
> > @@ -160,6 +164,9 @@ static void mirror_read_complete(void *opaque, 
> int ret)
> >          mirror_iteration_done(op, ret);
> >          return;
> >      }
> > +    op->backup_detect_zeroes = target->detect_zeroes;
> > +    target->detect_zeroes = s->unmap ? 
> BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP :
> > +        BLOCKDEV_DETECT_ZEROES_OPTIONS_ON;
> >      blk_aio_pwritev(s->target, op->sector_num * BDRV_SECTOR_SIZE, 
> &op->qiov,
> >                      0, mirror_write_complete, op);
> >  }
> > --
> > 2.10.2
> >
> >
>