[Qemu-devel] Re: lsi53c895a: add support for ABORT messages

[Aurelien Jarno <aurelien@aurel32.net>]

On Mon, Sep 06, 2010 at 04:42:54AM -0000, Bernhard Kohl wrote:
> If these messages are not handled correctly the guest driver may hang.
> 
> Always mandatory:
> - ABORT
> - BUS DEVICE RESET
> 
> Mandatory if tagged queuing is implemented (which disks usually do):
> - ABORT TAG
> - CLEAR QUEUE
> 
> Signed-off-by: Bernhard Kohl <bernhard.kohl@nsn.com>
> 
> ---
> hw/lsi53c895a.c |   57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 57 insertions(+), 0 deletions(-)

Thanks, applied.

> diff --git a/hw/lsi53c895a.c b/hw/lsi53c895a.c
> index 5eaf69e..40f2d10 100644
> --- a/hw/lsi53c895a.c
> +++ b/hw/lsi53c895a.c
> @@ -846,6 +846,18 @@ static void lsi_do_msgout(LSIState *s)
>  {
>      uint8_t msg;
>      int len;
> +    uint32_t current_tag;
> +    SCSIDevice *current_dev;
> +    lsi_request *p, *p_next;
> +    int id;
> +
> +    if (s->current) {
> +        current_tag = s->current->tag;
> +    } else {
> +        current_tag = s->select_tag;
> +    }
> +    id = (current_tag >> 8) & 0xf;
> +    current_dev = s->bus.devs[id];
>  
>      DPRINTF("MSG out len=%d\n", s->dbc);
>      while (s->dbc) {
> @@ -890,6 +902,51 @@ static void lsi_do_msgout(LSIState *s)
>              BADF("ORDERED queue not implemented\n");
>              s->select_tag |= lsi_get_msgbyte(s) | LSI_TAG_VALID;
>              break;
> +        case 0x0d:
> +            /* The ABORT TAG message clears the current I/O process only. */
> +            DPRINTF("MSG: ABORT TAG tag=0x%x\n", current_tag);
> +            current_dev->info->cancel_io(current_dev, current_tag);
> +            lsi_disconnect(s);
> +            break;
> +        case 0x06:
> +        case 0x0e:
> +        case 0x0c:
> +            /* The ABORT message clears all I/O processes for the selecting
> +               initiator on the specified logical unit of the target. */
> +            if (msg == 0x06) {
> +                DPRINTF("MSG: ABORT tag=0x%x\n", current_tag);
> +            }
> +            /* The CLEAR QUEUE message clears all I/O processes for all
> +               initiators on the specified logical unit of the target. */
> +            if (msg == 0x0e) {
> +                DPRINTF("MSG: CLEAR QUEUE tag=0x%x\n", current_tag);
> +            }
> +            /* The BUS DEVICE RESET message clears all I/O processes for all
> +               initiators on all logical units of the target. */
> +            if (msg == 0x0c) {
> +                DPRINTF("MSG: BUS DEVICE RESET tag=0x%x\n", current_tag);
> +            }
> +
> +            /* clear the current I/O process */
> +            current_dev->info->cancel_io(current_dev, current_tag);
> +
> +            /* As the current implemented devices scsi_disk and scsi_generic
> +               only support one LUN, we don't need to keep track of LUNs.
> +               Clearing I/O processes for other initiators could be possible
> +               for scsi_generic by sending a SG_SCSI_RESET to the /dev/sgX
> +               device, but this is currently not implemented (and seems not
> +               to be really necessary). So let's simply clear all queued
> +               commands for the current device: */
> +            id = current_tag & 0x0000ff00;
> +            QTAILQ_FOREACH_SAFE(p, &s->queue, next, p_next) {
> +                if ((p->tag & 0x0000ff00) == id) {
> +                    current_dev->info->cancel_io(current_dev, p->tag);
> +                    QTAILQ_REMOVE(&s->queue, p, next);
> +                }
> +            }
> +
> +            lsi_disconnect(s);
> +            break;
>          default:
>              if ((msg & 0x80) == 0) {
>                  goto bad;

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net