On Fri, Aug 04, 2017 at 10:37:54AM +0100, Stefan Hajnoczi wrote:
> On Wed, Jul 26, 2017 at 03:32:23PM +0100, Stefan Hajnoczi wrote:
> > The message printed on disk resize is incorrect. The following is
> > printed when resizing to 2 GiB:
> >
> > $ truncate -s 1G test.img
> > $ qemu -device virtio-blk-pci,logical_block_size=4096,...
> > (qemu) block_resize drive1 2G
> >
> > virtio_blk virtio0: new size: 4194304 4096-byte logical blocks (17.2
> > GB/16.0 GiB)
> >
> > The virtio_blk capacity config field is in 512-byte sector units
> > regardless of logical_block_size as per the VIRTIO specification.
> > Therefore the message should read:
> >
> > virtio_blk virtio0: new size: 524288 4096-byte logical blocks (2.15
> > GB/2.0 GiB)
> >
> > Note that this only affects the printed message. Thankfully the actual
> > block device has the correct size because the block layer expects
> > capacity in sectors.
> >
> > Signed-off-by: Stefan Hajnoczi <[email protected]>
> > ---
> > drivers/block/virtio_blk.c | 16 ++++++++++------
> > 1 file changed, 10 insertions(+), 6 deletions(-)
>
> Ping?
Oops - I thought I sent it up. Will do.
> > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
> > index 4e02aa5fdac0..69a2d1748743 100644
> > --- a/drivers/block/virtio_blk.c
> > +++ b/drivers/block/virtio_blk.c
> > @@ -381,6 +381,7 @@ static void virtblk_config_changed_work(struct
> > work_struct *work)
> > struct request_queue *q = vblk->disk->queue;
> > char cap_str_2[10], cap_str_10[10];
> > char *envp[] = { "RESIZE=1", NULL };
> > + unsigned long long nblocks;
> > u64 capacity;
> >
> > /* Host must always specify the capacity. */
> > @@ -393,16 +394,19 @@ static void virtblk_config_changed_work(struct
> > work_struct *work)
> > capacity = (sector_t)-1;
> > }
> >
> > - string_get_size(capacity, queue_logical_block_size(q),
> > + nblocks = DIV_ROUND_UP_ULL(capacity, queue_logical_block_size(q) >> 9);
> > +
> > + string_get_size(nblocks, queue_logical_block_size(q),
> > STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
> > - string_get_size(capacity, queue_logical_block_size(q),
> > + string_get_size(nblocks, queue_logical_block_size(q),
> > STRING_UNITS_10, cap_str_10, sizeof(cap_str_10));
> >
> > dev_notice(&vdev->dev,
> > - "new size: %llu %d-byte logical blocks (%s/%s)\n",
> > - (unsigned long long)capacity,
> > - queue_logical_block_size(q),
> > - cap_str_10, cap_str_2);
> > + "new size: %llu %d-byte logical blocks (%s/%s)\n",
> > + nblocks,
> > + queue_logical_block_size(q),
> > + cap_str_10,
> > + cap_str_2);
> >
> > set_capacity(vblk->disk, capacity);
> > revalidate_disk(vblk->disk);
> > --
> > 2.13.3
> >
