Re: [PATCH V2 WIP 0/2] vhost-scsi: new device supporting the tcm_vhost Linux kernel module

Asias He
2013-03-14T09:25:42Z

On Thu, Mar 14, 2013 at 12:25:14PM +0800, Asias He wrote:
> On Tue, Mar 12, 2013 at 02:29:40PM +0800, Asias He wrote:
> > This is on top of Paolo and Nick's work.
> >
> > Current status:
> > Works now (guest boots fine, no hang any more) with seabios's virtio-scsi disabled.
> > Rebased to latest qemu.org/master
> > Change details are in commit log.
> >
> > TODO:
> > Make seabios happy.
>
> Some updates:
>
> In seabios, src/virtio-scsi.c:virtio_scsi_cmd()
>
> vring_kick(ioaddr, vq, 1);
> /* Wait for reply */
> while (!vring_more_used(vq)) ------------>>> we hang here
> usleep(5);
>
> In tcm_vhost:
> we got: vhost_get_vq_desc: head: -14, out: 0 in: 81216
>
> The vring buffer provided by seabios is not correct?

More updates:

Basically, seabios + tcm_vhost works now, with the attached qemu and
seabios patches.

We still have one more issue, vhost_verify_ring_mappings fails.

I am seeing this without the comment out hack.

Unable to map ring buffer for ring 2
qemu-system-x86_64: /root/src/qemu/hw/vhost.c:426: vhost_set_memory:
Assertion `r >= 0' failed.

> > Paolo Bonzini (2):
> > virtio-scsi: create VirtIOSCSICommon
> > vhost-scsi: new device supporting the tcm_vhost Linux kernel module
> >
> > hw/Makefile.objs | 5 +-
> > hw/s390x/s390-virtio-bus.c | 35 +++++++
> > hw/vhost-scsi.c | 242 +++++++++++++++++++++++++++++++++++++++++++++
> > hw/vhost-scsi.h | 64 ++++++++++++
> > hw/virtio-pci.c | 59 +++++++++++
> > hw/virtio-scsi.c | 199 +++++++++----------------------------
> > hw/virtio-scsi.h | 129 ++++++++++++++++++++++++
> > include/qemu/osdep.h | 4 +
> > 8 files changed, 586 insertions(+), 151 deletions(-)
> > create mode 100644 hw/vhost-scsi.c
> > create mode 100644 hw/vhost-scsi.h
> >
> > --
> > 1.8.1.4
> >
>
> --
> Asias

--------------- 8 ---------------> qemu patch:
diff --git a/hw/vhost.c b/hw/vhost.c
index 4d6aee3..0c52ec4 100644
--- a/hw/vhost.c
+++ b/hw/vhost.c
@@ -421,10 +421,12 @@ static void vhost_set_memory(MemoryListener *listener,
return;
}

+#if 0
if (dev->started) {
r = vhost_verify_ring_mappings(dev, start_addr, size);
assert(r >= 0);
}
+#endif

if (!dev->log_enabled) {
r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);

--------------- 8 ---------------> seabios patch:
diff --git a/src/virtio-scsi.c b/src/virtio-scsi.c
index 879ddfb..4de1255 100644
--- a/src/virtio-scsi.c
+++ b/src/virtio-scsi.c
@@ -147,6 +147,9 @@ init_virtio_scsi(struct pci_device *pci)
goto fail;
}

+ vp_set_status(ioaddr, VIRTIO_CONFIG_S_ACKNOWLEDGE |
+ VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK);
+
int i, tot;
for (tot = 0, i = 0; i < 256; i++)
tot += virtio_scsi_scan_target(pci, ioaddr, vq, i);
@@ -154,8 +157,6 @@ init_virtio_scsi(struct pci_device *pci)
if (!tot)
goto fail;

- vp_set_status(ioaddr, VIRTIO_CONFIG_S_ACKNOWLEDGE |
- VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK);
return;

fail:
diff --git a/src/virtio-scsi.h b/src/virtio-scsi.h
index bbfbf30..96c3701 100644
--- a/src/virtio-scsi.h
+++ b/src/virtio-scsi.h
@@ -26,7 +26,7 @@ struct virtio_scsi_req_cmd {
u8 prio;
u8 crn;
char cdb[VIRTIO_SCSI_CDB_SIZE];
-};
+} __attribute__((packed));

/* This is the first element of the "in" scatter-gather list. */
struct virtio_scsi_resp_cmd {
@@ -36,7 +36,7 @@ struct virtio_scsi_resp_cmd {
u8 status;
u8 response;
u8 sense[VIRTIO_SCSI_SENSE_SIZE];
-};
+} __attribute__((packed));

#define VIRTIO_SCSI_S_OK 0

--
Asias