[PATCH v2] virtio-scsi: Send "REPORTED LUNS CHANGED" sense data upon disk hotplug events.

qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed

* [PATCH v2] virtio-scsi: Send "REPORTED LUNS CHANGED" sense data upon disk hotplug events.
@ 2022-09-15 23:33 Venu Busireddy
  2022-09-21 14:33 ` Paolo Bonzini
  0 siblings, 1 reply; 3+ messages in thread
From: Venu Busireddy @ 2022-09-15 23:33 UTC (permalink / raw)
  To: venu.busireddy, qemu-devel; +Cc: Fam Zheng, Michael S. Tsirkin, Paolo Bonzini

Section 5.6.6.3 of VirtIO specification states, "Events will also
be reported via sense codes..." However, no sense data is sent when
VIRTIO_SCSI_EVT_RESET_RESCAN or VIRTIO_SCSI_EVT_RESET_REMOVED events
are reported (when disk hotplug/hotunplug events occur). SCSI layer
on Solaris depends on this sense data, and hence does not handle disk
hotplug/hotunplug events.

As specified in SAM-4, Section 5.14 (h), return a CHECK_CONDITION status
with sense data of 0x06/0x3F/0x0E (sense code REPORTED_LUNS_CHANGED) when
the disk inventory changes and a command other than INQUIRY, REPORT_LUNS,
or REQUEST_SENSE is received.

Signed-off-by: Venu Busireddy <venu.busireddy@oracle.com>

v1 -> v2:
    - Send the sense data for VIRTIO_SCSI_EVT_RESET_REMOVED event too.
---
 hw/scsi/virtio-scsi.c           | 16 +++++++++++++++-
 include/hw/virtio/virtio-scsi.h |  1 +
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 41f2a5630173..69194c7ae23c 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -608,7 +608,19 @@ static void virtio_scsi_command_complete(SCSIRequest *r, size_t resid)
 
     req->resp.cmd.response = VIRTIO_SCSI_S_OK;
     req->resp.cmd.status = r->status;
-    if (req->resp.cmd.status == GOOD) {
+    if (req->dev->reported_luns_changed &&
+            (req->req.cmd.cdb[0] != INQUIRY) &&
+            (req->req.cmd.cdb[0] != REPORT_LUNS) &&
+            (req->req.cmd.cdb[0] != REQUEST_SENSE)) {
+        req->dev->reported_luns_changed = false;
+        req->resp.cmd.resid = 0;
+        req->resp.cmd.status_qualifier = 0;
+        req->resp.cmd.status = CHECK_CONDITION;
+        sense_len = scsi_build_sense(sense, SENSE_CODE(REPORTED_LUNS_CHANGED));
+        qemu_iovec_from_buf(&req->resp_iov, sizeof(req->resp.cmd),
+                            sense, sense_len);
+        req->resp.cmd.sense_len = virtio_tswap32(vdev, sense_len);
+    } else if (req->resp.cmd.status == GOOD) {
         req->resp.cmd.resid = virtio_tswap32(vdev, resid);
     } else {
         req->resp.cmd.resid = 0;
@@ -956,6 +968,7 @@ static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev,
         virtio_scsi_push_event(s, sd,
                                VIRTIO_SCSI_T_TRANSPORT_RESET,
                                VIRTIO_SCSI_EVT_RESET_RESCAN);
+        s->reported_luns_changed = true;
         virtio_scsi_release(s);
     }
 }
@@ -973,6 +986,7 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev,
         virtio_scsi_push_event(s, sd,
                                VIRTIO_SCSI_T_TRANSPORT_RESET,
                                VIRTIO_SCSI_EVT_RESET_REMOVED);
+        s->reported_luns_changed = true;
         virtio_scsi_release(s);
     }
 
diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
index a36aad9c8695..efbcf9ba069a 100644
--- a/include/hw/virtio/virtio-scsi.h
+++ b/include/hw/virtio/virtio-scsi.h
@@ -81,6 +81,7 @@ struct VirtIOSCSI {
     SCSIBus bus;
     int resetting;
     bool events_dropped;
+    bool reported_luns_changed;
 
     /* Fields for dataplane below */
     AioContext *ctx; /* one iothread per virtio-scsi-pci for now */


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH v2] virtio-scsi: Send "REPORTED LUNS CHANGED" sense data upon disk hotplug events.
  2022-09-15 23:33 [PATCH v2] virtio-scsi: Send "REPORTED LUNS CHANGED" sense data upon disk hotplug events Venu Busireddy
@ 2022-09-21 14:33 ` Paolo Bonzini
  2022-09-21 14:40   ` Venu Busireddy
  0 siblings, 1 reply; 3+ messages in thread
From: Paolo Bonzini @ 2022-09-21 14:33 UTC (permalink / raw)
  To: Venu Busireddy; +Cc: qemu-devel, Fam Zheng, Michael S. Tsirkin

On Fri, Sep 16, 2022 at 3:44 AM Venu Busireddy
<venu.busireddy@oracle.com> wrote:
> diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
> index 41f2a5630173..69194c7ae23c 100644
> --- a/hw/scsi/virtio-scsi.c
> +++ b/hw/scsi/virtio-scsi.c
> @@ -608,7 +608,19 @@ static void virtio_scsi_command_complete(SCSIRequest *r, size_t resid)
>
>      req->resp.cmd.response = VIRTIO_SCSI_S_OK;
>      req->resp.cmd.status = r->status;
> -    if (req->resp.cmd.status == GOOD) {
> +    if (req->dev->reported_luns_changed &&
> +            (req->req.cmd.cdb[0] != INQUIRY) &&
> +            (req->req.cmd.cdb[0] != REPORT_LUNS) &&
> +            (req->req.cmd.cdb[0] != REQUEST_SENSE)) {
> +        req->dev->reported_luns_changed = false;
> +        req->resp.cmd.resid = 0;
> +        req->resp.cmd.status_qualifier = 0;
> +        req->resp.cmd.status = CHECK_CONDITION;
> +        sense_len = scsi_build_sense(sense, SENSE_CODE(REPORTED_LUNS_CHANGED));
> +        qemu_iovec_from_buf(&req->resp_iov, sizeof(req->resp.cmd),
> +                            sense, sense_len);
> +        req->resp.cmd.sense_len = virtio_tswap32(vdev, sense_len);
> +    } else if (req->resp.cmd.status == GOOD) {
>          req->resp.cmd.resid = virtio_tswap32(vdev, resid);
>      } else {
>          req->resp.cmd.resid = 0;

Hi,

a unit attention sense must be sent _instead_ of executing the command.

QEMU already has a function scsi_device_set_ua() that handles
everything; you have to call it, if reported_luns_changed is true,
from virtio_scsi_handle_cmd_req_prepare() before scsi_req_new().

It will also skip GET_CONFIGURATION and GET_EVENT_STATUS_NOTIFICATION
commands which are further special-cased in 4.1.6.1 of the MMC
specification.

Thanks,

Paolo


> @@ -956,6 +968,7 @@ static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev,
>          virtio_scsi_push_event(s, sd,
>                                 VIRTIO_SCSI_T_TRANSPORT_RESET,
>                                 VIRTIO_SCSI_EVT_RESET_RESCAN);
> +        s->reported_luns_changed = true;
>          virtio_scsi_release(s);
>      }
>  }
> @@ -973,6 +986,7 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev,
>          virtio_scsi_push_event(s, sd,
>                                 VIRTIO_SCSI_T_TRANSPORT_RESET,
>                                 VIRTIO_SCSI_EVT_RESET_REMOVED);
> +        s->reported_luns_changed = true;
>          virtio_scsi_release(s);
>      }
>
> diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
> index a36aad9c8695..efbcf9ba069a 100644
> --- a/include/hw/virtio/virtio-scsi.h
> +++ b/include/hw/virtio/virtio-scsi.h
> @@ -81,6 +81,7 @@ struct VirtIOSCSI {
>      SCSIBus bus;
>      int resetting;
>      bool events_dropped;
> +    bool reported_luns_changed;
>
>      /* Fields for dataplane below */
>      AioContext *ctx; /* one iothread per virtio-scsi-pci for now */
>



^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH v2] virtio-scsi: Send "REPORTED LUNS CHANGED" sense data upon disk hotplug events.
  2022-09-21 14:33 ` Paolo Bonzini
@ 2022-09-21 14:40   ` Venu Busireddy
  0 siblings, 0 replies; 3+ messages in thread
From: Venu Busireddy @ 2022-09-21 14:40 UTC (permalink / raw)
  To: Paolo Bonzini; +Cc: qemu-devel, Fam Zheng, Michael S. Tsirkin

On 2022-09-21 16:33:35 +0200, Paolo Bonzini wrote:
> On Fri, Sep 16, 2022 at 3:44 AM Venu Busireddy
> <venu.busireddy@oracle.com> wrote:
> > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
> > index 41f2a5630173..69194c7ae23c 100644
> > --- a/hw/scsi/virtio-scsi.c
> > +++ b/hw/scsi/virtio-scsi.c
> > @@ -608,7 +608,19 @@ static void virtio_scsi_command_complete(SCSIRequest *r, size_t resid)
> >
> >      req->resp.cmd.response = VIRTIO_SCSI_S_OK;
> >      req->resp.cmd.status = r->status;
> > -    if (req->resp.cmd.status == GOOD) {
> > +    if (req->dev->reported_luns_changed &&
> > +            (req->req.cmd.cdb[0] != INQUIRY) &&
> > +            (req->req.cmd.cdb[0] != REPORT_LUNS) &&
> > +            (req->req.cmd.cdb[0] != REQUEST_SENSE)) {
> > +        req->dev->reported_luns_changed = false;
> > +        req->resp.cmd.resid = 0;
> > +        req->resp.cmd.status_qualifier = 0;
> > +        req->resp.cmd.status = CHECK_CONDITION;
> > +        sense_len = scsi_build_sense(sense, SENSE_CODE(REPORTED_LUNS_CHANGED));
> > +        qemu_iovec_from_buf(&req->resp_iov, sizeof(req->resp.cmd),
> > +                            sense, sense_len);
> > +        req->resp.cmd.sense_len = virtio_tswap32(vdev, sense_len);
> > +    } else if (req->resp.cmd.status == GOOD) {
> >          req->resp.cmd.resid = virtio_tswap32(vdev, resid);
> >      } else {
> >          req->resp.cmd.resid = 0;
> 
> Hi,
> 
> a unit attention sense must be sent _instead_ of executing the command.
> 
> QEMU already has a function scsi_device_set_ua() that handles
> everything; you have to call it, if reported_luns_changed is true,
> from virtio_scsi_handle_cmd_req_prepare() before scsi_req_new().
> 
> It will also skip GET_CONFIGURATION and GET_EVENT_STATUS_NOTIFICATION
> commands which are further special-cased in 4.1.6.1 of the MMC
> specification.

Thanks, Paolo. I will test your suggestion (as soon as I finish what I
am working currently), and get back with either more questions, or with
a v3 post.

Venu

> > @@ -956,6 +968,7 @@ static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev,
> >          virtio_scsi_push_event(s, sd,
> >                                 VIRTIO_SCSI_T_TRANSPORT_RESET,
> >                                 VIRTIO_SCSI_EVT_RESET_RESCAN);
> > +        s->reported_luns_changed = true;
> >          virtio_scsi_release(s);
> >      }
> >  }
> > @@ -973,6 +986,7 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev,
> >          virtio_scsi_push_event(s, sd,
> >                                 VIRTIO_SCSI_T_TRANSPORT_RESET,
> >                                 VIRTIO_SCSI_EVT_RESET_REMOVED);
> > +        s->reported_luns_changed = true;
> >          virtio_scsi_release(s);
> >      }
> >
> > diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
> > index a36aad9c8695..efbcf9ba069a 100644
> > --- a/include/hw/virtio/virtio-scsi.h
> > +++ b/include/hw/virtio/virtio-scsi.h
> > @@ -81,6 +81,7 @@ struct VirtIOSCSI {
> >      SCSIBus bus;
> >      int resetting;
> >      bool events_dropped;
> > +    bool reported_luns_changed;
> >
> >      /* Fields for dataplane below */
> >      AioContext *ctx; /* one iothread per virtio-scsi-pci for now */
> >
> 


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2022-09-21 14:44 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-09-15 23:33 [PATCH v2] virtio-scsi: Send "REPORTED LUNS CHANGED" sense data upon disk hotplug events Venu Busireddy
2022-09-21 14:33 ` Paolo Bonzini
2022-09-21 14:40   ` Venu Busireddy

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).