Re: [Qemu-devel] [PATCH 2/3] s390x/css: support format-0 ccws

[Christian Borntraeger <borntraeger@de.ibm.com>]

On 05/09/14 00:29, Alexander Graf wrote:
> 
> 
> On 04.09.14 17:32, Jens Freimann wrote:
>> From: Cornelia Huck <cornelia.huck@de.ibm.com>
>>
>> Add support for format-0 ccws in channel programs. As a format-1 ccw
>> contains the same information as format-0 ccws, only supporting larger
>> addresses, simply convert every ccw to format-1 as we walk the chain.
>>
>> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
>> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
>> ---
>>  hw/s390x/css.c        | 30 +++++++++++++++++++++---------
>>  hw/s390x/css.h        |  1 +
>>  target-s390x/ioinst.h | 10 ++++++++++
>>  3 files changed, 32 insertions(+), 9 deletions(-)
>>
>> diff --git a/hw/s390x/css.c b/hw/s390x/css.c
>> index 49c2aaf..34637cb 100644
>> --- a/hw/s390x/css.c
>> +++ b/hw/s390x/css.c
>> @@ -243,17 +243,25 @@ static void copy_sense_id_to_guest(SenseId *dest, SenseId *src)
>>      }
>>  }
>>  
>> -static CCW1 copy_ccw_from_guest(hwaddr addr)
>> +static CCW1 copy_ccw_from_guest(hwaddr addr, bool fmt1)
>>  {
>> -    CCW1 tmp;
>> +    CCW0 tmp0;
>> +    CCW1 tmp1;
>>      CCW1 ret;
>>  
>> -    cpu_physical_memory_read(addr, &tmp, sizeof(tmp));
>> -    ret.cmd_code = tmp.cmd_code;
>> -    ret.flags = tmp.flags;
>> -    ret.count = be16_to_cpu(tmp.count);
>> -    ret.cda = be32_to_cpu(tmp.cda);
>> -
>> +    if (fmt1) {
>> +        cpu_physical_memory_read(addr, &tmp1, sizeof(tmp1));
>> +        ret.cmd_code = tmp1.cmd_code;
>> +        ret.flags = tmp1.flags;
>> +        ret.count = be16_to_cpu(tmp1.count);
>> +        ret.cda = be32_to_cpu(tmp1.cda);
>> +    } else {
>> +        cpu_physical_memory_read(addr, &tmp0, sizeof(tmp0));
>> +        ret.cmd_code = tmp0.cmd_code;
>> +        ret.flags = tmp0.flags;
>> +        ret.count = be16_to_cpu(tmp0.count);
>> +        ret.cda = be16_to_cpu(tmp0.cda1) | (tmp0.cda0 << 16);
>> +    }
>>      return ret;
>>  }
>>  
>> @@ -268,7 +276,8 @@ static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr)
>>          return -EIO;
>>      }
>>  
>> -    ccw = copy_ccw_from_guest(ccw_addr);
>> +    /* Translate everything to format-1 ccws - the information is the same. */
>> +    ccw = copy_ccw_from_guest(ccw_addr, sch->ccw_fmt_1);
>>  
>>      /* Check for invalid command codes. */
>>      if ((ccw.cmd_code & 0x0f) == 0) {
>> @@ -386,6 +395,7 @@ static void sch_handle_start_func(SubchDev *sch, ORB *orb)
>>              s->ctrl |= (SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND);
>>              return;
>>          }
>> +        sch->ccw_fmt_1 = !!(orb->ctrl0 & ORB_CTRL0_MASK_FMT);
>>      } else {
>>          s->ctrl &= ~(SCSW_ACTL_SUSP | SCSW_ACTL_RESUME_PEND);
>>      }
>> @@ -1347,6 +1357,7 @@ void subch_device_save(SubchDev *s, QEMUFile *f)
>>          qemu_put_byte(f, s->id.ciw[i].command);
>>          qemu_put_be16(f, s->id.ciw[i].count);
>>      }
>> +    qemu_put_byte(f, s->ccw_fmt_1);
> 
> This changes the migration stream format. Please increase the version
> number for the device that gets migrated, so that we have the chance to
> catch it.
> 
> Though - does migration work at all yet? :)

Not yet.
Myself and Jens are currently testing Davids latest patches regarding CPU states. (just chasing the final (tm) bug). 
After that I can push the initial cpu migration patch set.
So maybe we can leave this as is? Whatever you suggest.


> 
> 
> Alex
> 
>>      return;
>>  }
>>  
>> @@ -1402,6 +1413,7 @@ int subch_device_load(SubchDev *s, QEMUFile *f)
>>          s->id.ciw[i].command = qemu_get_byte(f);
>>          s->id.ciw[i].count = qemu_get_be16(f);
>>      }
>> +    s->ccw_fmt_1 = qemu_get_byte(f);
>>      return 0;
>>  }
>>  
>> diff --git a/hw/s390x/css.h b/hw/s390x/css.h
>> index c864ea7..384a455 100644
>> --- a/hw/s390x/css.h
>> +++ b/hw/s390x/css.h
>> @@ -76,6 +76,7 @@ struct SubchDev {
>>      hwaddr channel_prog;
>>      CCW1 last_cmd;
>>      bool last_cmd_valid;
>> +    bool ccw_fmt_1;
>>      bool thinint_active;
>>      /* transport-provided data: */
>>      int (*ccw_cb) (SubchDev *, CCW1);
>> diff --git a/target-s390x/ioinst.h b/target-s390x/ioinst.h
>> index 5bbc67d..29f6423 100644
>> --- a/target-s390x/ioinst.h
>> +++ b/target-s390x/ioinst.h
>> @@ -156,6 +156,16 @@ typedef struct ORB {
>>  #define ORB_CTRL1_MASK_ORBX 0x01
>>  #define ORB_CTRL1_MASK_INVALID 0x3e
>>  
>> +/* channel command word (type 0) */
>> +typedef struct CCW0 {
>> +        uint8_t cmd_code;
>> +        uint8_t cda0;
>> +        uint16_t cda1;
>> +        uint8_t flags;
>> +        uint8_t reserved;
>> +        uint16_t count;
>> +} QEMU_PACKED CCW0;
>> +
>>  /* channel command word (type 1) */
>>  typedef struct CCW1 {
>>      uint8_t cmd_code;
>>
>