On Sat, 30 Aug 2025 22:39:54 +0200 Heinrich Schuchardt <[email protected]> wrote:
Hi Heinrich, > QEMU allows to specify the logical block size via parameter > logical_block_size of a virtio-blk-device. > > The communication channel via virtqueues remains based on 512 byte blocks > even if the logical_block_size is larger. > > Consider the logical block size in the block device driver. > > Reported-by: Emil Renner Berthing <[email protected]> > Signed-off-by: Heinrich Schuchardt <[email protected]> > --- > v2: > remove superfluous include linux/err.h > --- > drivers/virtio/virtio_blk.c | 25 ++++++++++++++++++++++--- > 1 file changed, 22 insertions(+), 3 deletions(-) > > diff --git a/drivers/virtio/virtio_blk.c b/drivers/virtio/virtio_blk.c > index 2f999fc8bbe..4224e3c17f4 100644 > --- a/drivers/virtio/virtio_blk.c > +++ b/drivers/virtio/virtio_blk.c > @@ -12,10 +12,17 @@ > #include <virtio_types.h> > #include <virtio.h> > #include <virtio_ring.h> > +#include <linux/log2.h> > #include "virtio_blk.h" > > +/** > + * struct virtio_blk_priv - private date for virtio block device > + */ > struct virtio_blk_priv { > + /** @virtqueue - virtqueue to process */ > struct virtqueue *vq; > + /** @blksz_shift - log2 of block size divided by 512 */ > + u32 blksz_shift; > }; > > static const u32 feature[] = { > @@ -71,6 +78,8 @@ static ulong virtio_blk_do_req(struct udevice *dev, u64 > sector, > u8 status; > int ret; > > + sector <<= priv->blksz_shift; > + blkcnt <<= priv->blksz_shift; > virtio_blk_init_header_sg(dev, sector, type, &out_hdr, &hdr_sg); > sgs[num_out++] = &hdr_sg; > > @@ -109,7 +118,7 @@ static ulong virtio_blk_do_req(struct udevice *dev, u64 > sector, > ; > log_debug("done\n"); > > - return status == VIRTIO_BLK_S_OK ? blkcnt : -EIO; > + return status == VIRTIO_BLK_S_OK ? blkcnt >> priv->blksz_shift : -EIO; > } > > static ulong virtio_blk_read(struct udevice *dev, lbaint_t start, > @@ -177,15 +186,25 @@ static int virtio_blk_probe(struct udevice *dev) > struct blk_desc *desc = dev_get_uclass_plat(dev); > u64 cap; > int ret; > + u32 blk_size; > > ret = virtio_find_vqs(dev, 1, &priv->vq); > if (ret) > return ret; > > - desc->blksz = 512; > - desc->log2blksz = 9; > virtio_cread(dev, struct virtio_blk_config, capacity, &cap); > desc->lba = cap; > + if (!virtio_has_feature(dev, VIRTIO_BLK_F_BLK_SIZE)) { Is that actually the right condition check? I would assume that we only query the blk_size field if the feature bit is *set*, not when it's cleared? We see a failure (virtio block device not registering), because blk_size is 0 on the Arm FVP fast model, which is fine I think because the feature bit is clear as well. Cheers, Andre > + virtio_cread(dev, struct virtio_blk_config, blk_size, > &blk_size); > + desc->blksz = blk_size; > + if (!is_power_of_2(blk_size) || desc->blksz < 512) > + return -EIO; > + } else { > + desc->blksz = 512; > + } > + desc->log2blksz = LOG2(desc->blksz); > + priv->blksz_shift = desc->log2blksz - 9; > + desc->lba >>= priv->blksz_shift; > > return 0; > }
