Message ID | 1404480720-7485-3-git-send-email-armbru@redhat.com |
---|---|
State | New |
Headers | show |
Am 04.07.2014 um 15:31 hat Markus Armbruster geschrieben: > When a device model's I/O operation fails, we execute the error > action. This lets layers above QEMU implement thin provisioning, or > attempt to correct errors before they reach the guest. But when the > I/O operation fails because it's invalid, reporting the error to the > guest is the only sensible action. > > If the guest's read or write asks for an invalid sector range, fail > the request right away, without considering the error action. No > change with error action BDRV_ACTION_REPORT. > > Furthermore, bypass I/O accounting, because we want to track only I/O > that actually reaches the block layer. > > The next commit will extend "invalid sector range" to cover attempts > to read/write beyond the end of the medium. > > Signed-off-by: Markus Armbruster <armbru@redhat.com> > Reviewed-by: Fam Zheng <famz@redhat.com> > --- > hw/block/virtio-blk.c | 14 ++++++++------ > 1 file changed, 8 insertions(+), 6 deletions(-) > > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c > index d946fa9..c8952c0 100644 > --- a/hw/block/virtio-blk.c > +++ b/hw/block/virtio-blk.c > @@ -307,15 +307,16 @@ static void virtio_blk_handle_write(VirtIOBlockReq *req, MultiReqBuffer *mrb) > > sector = virtio_ldq_p(VIRTIO_DEVICE(req->dev), &req->out.sector); > > - bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_WRITE); > - > trace_virtio_blk_handle_write(req, sector, req->qiov.size / 512); > > if (!virtio_blk_sect_range_ok(req->dev, sector, req->qiov.size)) { > - virtio_blk_rw_complete(req, -EIO); > + virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); > + g_free(req); This should probably be virtio_blk_free_request() now, which was only recently introduced. > return; > } > > + bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_WRITE); > + > if (mrb->num_writes == 32) { > virtio_submit_multiwrite(req->dev->bs, mrb); > } > @@ -337,14 +338,15 @@ static void virtio_blk_handle_read(VirtIOBlockReq *req) > > sector = virtio_ldq_p(VIRTIO_DEVICE(req->dev), &req->out.sector); > > - bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_READ); > - > trace_virtio_blk_handle_read(req, sector, req->qiov.size / 512); > > if (!virtio_blk_sect_range_ok(req->dev, sector, req->qiov.size)) { > - virtio_blk_rw_complete(req, -EIO); > + virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); > + g_free(req); Same here. > return; > } > + > + bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_READ); > bdrv_aio_readv(req->dev->bs, sector, &req->qiov, > req->qiov.size / BDRV_SECTOR_SIZE, > virtio_blk_rw_complete, req); Kevin
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index d946fa9..c8952c0 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -307,15 +307,16 @@ static void virtio_blk_handle_write(VirtIOBlockReq *req, MultiReqBuffer *mrb) sector = virtio_ldq_p(VIRTIO_DEVICE(req->dev), &req->out.sector); - bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_WRITE); - trace_virtio_blk_handle_write(req, sector, req->qiov.size / 512); if (!virtio_blk_sect_range_ok(req->dev, sector, req->qiov.size)) { - virtio_blk_rw_complete(req, -EIO); + virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); + g_free(req); return; } + bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_WRITE); + if (mrb->num_writes == 32) { virtio_submit_multiwrite(req->dev->bs, mrb); } @@ -337,14 +338,15 @@ static void virtio_blk_handle_read(VirtIOBlockReq *req) sector = virtio_ldq_p(VIRTIO_DEVICE(req->dev), &req->out.sector); - bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_READ); - trace_virtio_blk_handle_read(req, sector, req->qiov.size / 512); if (!virtio_blk_sect_range_ok(req->dev, sector, req->qiov.size)) { - virtio_blk_rw_complete(req, -EIO); + virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); + g_free(req); return; } + + bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_READ); bdrv_aio_readv(req->dev->bs, sector, &req->qiov, req->qiov.size / BDRV_SECTOR_SIZE, virtio_blk_rw_complete, req);