Re: [Qemu-devel] [PATCH v3 3/6] block/nvme: support larger that 512 bytes sector devices

[Maxim Levitsky]

On Fri, 2019-07-05 at 13:58 +0200, Max Reitz wrote:
> On 03.07.19 17:59, Maxim Levitsky wrote:
> > Currently the driver hardcodes the sector size to 512,
> > and doesn't check the underlying device. Fix that.
> > 
> > Also fail if underlying nvme device is formatted with metadata
> > as this needs special support.
> > 
> > Signed-off-by: Maxim Levitsky <address@hidden>
> > ---
> >  block/nvme.c | 45 ++++++++++++++++++++++++++++++++++++++++-----
> >  1 file changed, 40 insertions(+), 5 deletions(-)
> > 
> > diff --git a/block/nvme.c b/block/nvme.c
> > index 52798081b2..1f0d09349f 100644
> > --- a/block/nvme.c
> > +++ b/block/nvme.c
> 
> [...]
> 
> > @@ -463,7 +467,22 @@ static void nvme_identify(BlockDriverState *bs, int 
> > namespace, Error **errp)
> >      }
> >  
> >      s->nsze = le64_to_cpu(idns->nsze);
> > +    lbaf = &idns->lbaf[NVME_ID_NS_FLBAS_INDEX(idns->flbas)];
> > +
> > +    if (lbaf->ms) {
> > +        error_setg(errp, "Namespaces with metadata are not yet supported");
> > +        goto out;
> > +    }
> > +
> > +    hwsect_size = 1 << lbaf->ds;
> > +
> > +    if (hwsect_size < BDRV_SECTOR_BITS || hwsect_size > s->page_size) {
> 
> s/BDRV_SECTOR_BITS/BDRV_SECTOR_SIZE/
Oops.

> 
> > +        error_setg(errp, "Namespace has unsupported block size (%d)",
> > +                hwsect_size);
> > +        goto out;
> > +    }
> >  
> > +    s->blkshift = lbaf->ds;
> >  out:
> >      qemu_vfio_dma_unmap(s->vfio, resp);
> >      qemu_vfree(resp);
> > @@ -782,8 +801,22 @@ fail:
> >  static int64_t nvme_getlength(BlockDriverState *bs)
> >  {
> >      BDRVNVMeState *s = bs->opaque;
> > +    return s->nsze << s->blkshift;
> > +}
> >  
> > -    return s->nsze << BDRV_SECTOR_BITS;
> > +static int64_t nvme_get_blocksize(BlockDriverState *bs)
> > +{
> > +    BDRVNVMeState *s = bs->opaque;
> > +    assert(s->blkshift >= 9);
> 
> I think BDRV_SECTOR_BITS is more correct here (this is about what the
> general block layer code expects).  Also, there’s no pain in doing so,
> as you did check against BDRV_SECTOR_SIZE in nvme_identify().
> Max
Of course, thanks!!

> 
> > +    return 1 << s->blkshift;
> > +}
> > +
> > +static int nvme_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz)
> > +{
> > +    int64_t blocksize = nvme_get_blocksize(bs);
> > +    bsz->phys = blocksize;
> > +    bsz->log = blocksize;
> > +    return 0;
> >  }
> >  
> >  /* Called with s->dma_map_lock */
> 
> 

Thanks for the review,
        Best regards,
                Maxim Levitsky