diff mbox series

[v3,12/16] s390-bios: Refactor virtio to run channel programs via cio

Message ID 1551466776-29123-13-git-send-email-jjherne@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390: vfio-ccw dasd ipl support | expand

Commit Message

Jason J. Herne March 1, 2019, 6:59 p.m. UTC 
Now that we have a Channel I/O library let's modify virtio boot code to
make use of it for running channel programs.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
---
 pc-bios/s390-ccw/virtio.c | 49 +++++++++++++++++++----------------------------
 1 file changed, 20 insertions(+), 29 deletions(-)

Comments

Cornelia Huck March 5, 2019, 12:30 p.m. UTC | #1 
On Fri,  1 Mar 2019 13:59:32 -0500
"Jason J. Herne" <jjherne@linux.ibm.com> wrote:

> Now that we have a Channel I/O library let's modify virtio boot code to
> make use of it for running channel programs.
> 
> Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
> ---
>  pc-bios/s390-ccw/virtio.c | 49 +++++++++++++++++++----------------------------
>  1 file changed, 20 insertions(+), 29 deletions(-)
> 
> diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
> index aa9da72..711daf5 100644
> --- a/pc-bios/s390-ccw/virtio.c
> +++ b/pc-bios/s390-ccw/virtio.c
> @@ -14,6 +14,7 @@
>  #include "virtio.h"
>  #include "virtio-scsi.h"
>  #include "bswap.h"
> +#include "helper.h"
>  
>  #define VRING_WAIT_REPLY_TIMEOUT 30
>  
> @@ -89,33 +90,20 @@ int drain_irqs(SubChannelId schid)
>      }
>  }
>  
> -static int run_ccw(VDev *vdev, int cmd, void *ptr, int len)
> +static int run_ccw(VDev *vdev, int cmd, void *ptr, int len, bool sli)
>  {
>      Ccw1 ccw = {};
> -    CmdOrb orb = {};
> -    int r;
> -
> -    enable_subchannel(vdev->schid);
> -
> -    /* start subchannel command */
> -    orb.fmt = 1;
> -    orb.cpa = (u32)(long)&ccw;
> -    orb.lpm = 0x80;
>  
>      ccw.cmd_code = cmd;
>      ccw.cda = (long)ptr;
>      ccw.count = len;
>  
> -    r = ssch(vdev->schid, &orb);
> -    /*
> -     * XXX Wait until device is done processing the CCW. For now we can
> -     *     assume that a simple tsch will have finished the CCW processing,
> -     *     but the architecture allows for asynchronous operation
> -     */
> -    if (!r) {
> -        r = drain_irqs(vdev->schid);
> +    if (sli) {
> +        ccw.flags |= CCW_FLAG_SLI;
>      }
> -    return r;
> +
> +    enable_subchannel(vdev->schid);

As said, maybe just move this to the main routine, instead of having to
call this here again and again.

> +    return do_cio(vdev->schid, ptr2u32(&ccw), CCW_FMT1);
>  }
>  
>  static void vring_init(VRing *vr, VqInfo *info)

(...)

> @@ -324,7 +314,8 @@ bool virtio_is_supported(SubChannelId schid)
>      vdev.schid = schid;
>      memset(&vdev.senseid, 0, sizeof(vdev.senseid));
>      /* run sense id command */
> -    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid))) {
> +    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid),
> +                true)) {
>          return false;
>      }
>      if (vdev.senseid.cu_type == 0x3832) {

Can't you use the new routine for obtaining the cu type here?
Jason J. Herne March 7, 2019, 3:09 p.m. UTC | #2 
On 3/5/19 7:30 AM, Cornelia Huck wrote:
> On Fri,  1 Mar 2019 13:59:32 -0500
> "Jason J. Herne" <jjherne@linux.ibm.com> wrote:
> 
>> Now that we have a Channel I/O library let's modify virtio boot code to
>> make use of it for running channel programs.
>>
>> Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
>> ---
>>   pc-bios/s390-ccw/virtio.c | 49 +++++++++++++++++++----------------------------
>>   1 file changed, 20 insertions(+), 29 deletions(-)
>>
>> diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
>> index aa9da72..711daf5 100644
>> --- a/pc-bios/s390-ccw/virtio.c
>> +++ b/pc-bios/s390-ccw/virtio.c
>> @@ -14,6 +14,7 @@
>>   #include "virtio.h"
>>   #include "virtio-scsi.h"
>>   #include "bswap.h"
>> +#include "helper.h"
>>   
>>   #define VRING_WAIT_REPLY_TIMEOUT 30
>>   
>> @@ -89,33 +90,20 @@ int drain_irqs(SubChannelId schid)
>>       }
>>   }
>>   
>> -static int run_ccw(VDev *vdev, int cmd, void *ptr, int len)
>> +static int run_ccw(VDev *vdev, int cmd, void *ptr, int len, bool sli)
>>   {
>>       Ccw1 ccw = {};
>> -    CmdOrb orb = {};
>> -    int r;
>> -
>> -    enable_subchannel(vdev->schid);
>> -
>> -    /* start subchannel command */
>> -    orb.fmt = 1;
>> -    orb.cpa = (u32)(long)&ccw;
>> -    orb.lpm = 0x80;
>>   
>>       ccw.cmd_code = cmd;
>>       ccw.cda = (long)ptr;
>>       ccw.count = len;
>>   
>> -    r = ssch(vdev->schid, &orb);
>> -    /*
>> -     * XXX Wait until device is done processing the CCW. For now we can
>> -     *     assume that a simple tsch will have finished the CCW processing,
>> -     *     but the architecture allows for asynchronous operation
>> -     */
>> -    if (!r) {
>> -        r = drain_irqs(vdev->schid);
>> +    if (sli) {
>> +        ccw.flags |= CCW_FLAG_SLI;
>>       }
>> -    return r;
>> +
>> +    enable_subchannel(vdev->schid);
> 
> As said, maybe just move this to the main routine, instead of having to
> call this here again and again.
> 

I can just remove this call all together, but because of the netboot case I'll need to add 
a call to enable_subchannel to virtio_is_supported() or find_net_dev().

netmain.c: main -> virtio_setup-> find_net_dev-> virtio_is_supported

Let me know if you like this idea or not. If you're okay with it, I'll queue it up for v4. 
IMHO, adding the call to find_net_dev makes more sense than virtio_is_supported.


>> +    return do_cio(vdev->schid, ptr2u32(&ccw), CCW_FMT1);
>>   }
>>   
>>   static void vring_init(VRing *vr, VqInfo *info)
> 
> (...)
> 
>> @@ -324,7 +314,8 @@ bool virtio_is_supported(SubChannelId schid)
>>       vdev.schid = schid;
>>       memset(&vdev.senseid, 0, sizeof(vdev.senseid));
>>       /* run sense id command */
>> -    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid))) {
>> +    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid),
>> +                true)) {
>>           return false;
>>       }
>>       if (vdev.senseid.cu_type == 0x3832) {
> 
> Can't you use the new routine for obtaining the cu type here?
> 

cu_type only returns the control unit type. This code goes on to look at the model number 
as well. In hind sight, I could have noticed this and simply structured my code to return 
the whole sense_id data structure. I'm not against making this change, but things seem 
pretty clean as they are. :)
Cornelia Huck March 7, 2019, 3:37 p.m. UTC | #3 
On Thu, 7 Mar 2019 10:09:46 -0500
"Jason J. Herne" <jjherne@linux.ibm.com> wrote:

> On 3/5/19 7:30 AM, Cornelia Huck wrote:
> > On Fri,  1 Mar 2019 13:59:32 -0500
> > "Jason J. Herne" <jjherne@linux.ibm.com> wrote:
> >   
> >> Now that we have a Channel I/O library let's modify virtio boot code to
> >> make use of it for running channel programs.
> >>
> >> Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
> >> ---
> >>   pc-bios/s390-ccw/virtio.c | 49 +++++++++++++++++++----------------------------
> >>   1 file changed, 20 insertions(+), 29 deletions(-)
> >>
> >> diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
> >> index aa9da72..711daf5 100644
> >> --- a/pc-bios/s390-ccw/virtio.c
> >> +++ b/pc-bios/s390-ccw/virtio.c
> >> @@ -14,6 +14,7 @@
> >>   #include "virtio.h"
> >>   #include "virtio-scsi.h"
> >>   #include "bswap.h"
> >> +#include "helper.h"
> >>   
> >>   #define VRING_WAIT_REPLY_TIMEOUT 30
> >>   
> >> @@ -89,33 +90,20 @@ int drain_irqs(SubChannelId schid)
> >>       }
> >>   }
> >>   
> >> -static int run_ccw(VDev *vdev, int cmd, void *ptr, int len)
> >> +static int run_ccw(VDev *vdev, int cmd, void *ptr, int len, bool sli)
> >>   {
> >>       Ccw1 ccw = {};
> >> -    CmdOrb orb = {};
> >> -    int r;
> >> -
> >> -    enable_subchannel(vdev->schid);
> >> -
> >> -    /* start subchannel command */
> >> -    orb.fmt = 1;
> >> -    orb.cpa = (u32)(long)&ccw;
> >> -    orb.lpm = 0x80;
> >>   
> >>       ccw.cmd_code = cmd;
> >>       ccw.cda = (long)ptr;
> >>       ccw.count = len;
> >>   
> >> -    r = ssch(vdev->schid, &orb);
> >> -    /*
> >> -     * XXX Wait until device is done processing the CCW. For now we can
> >> -     *     assume that a simple tsch will have finished the CCW processing,
> >> -     *     but the architecture allows for asynchronous operation
> >> -     */
> >> -    if (!r) {
> >> -        r = drain_irqs(vdev->schid);
> >> +    if (sli) {
> >> +        ccw.flags |= CCW_FLAG_SLI;
> >>       }
> >> -    return r;
> >> +
> >> +    enable_subchannel(vdev->schid);  
> > 
> > As said, maybe just move this to the main routine, instead of having to
> > call this here again and again.
> >   
> 
> I can just remove this call all together, but because of the netboot case I'll need to add 
> a call to enable_subchannel to virtio_is_supported() or find_net_dev().
> 
> netmain.c: main -> virtio_setup-> find_net_dev-> virtio_is_supported
> 
> Let me know if you like this idea or not. If you're okay with it, I'll queue it up for v4. 
> IMHO, adding the call to find_net_dev makes more sense than virtio_is_supported.

I think adding the call to find_net_dev() would make sense.

> 
> 
> >> +    return do_cio(vdev->schid, ptr2u32(&ccw), CCW_FMT1);
> >>   }
> >>   
> >>   static void vring_init(VRing *vr, VqInfo *info)  
> > 
> > (...)
> >   
> >> @@ -324,7 +314,8 @@ bool virtio_is_supported(SubChannelId schid)
> >>       vdev.schid = schid;
> >>       memset(&vdev.senseid, 0, sizeof(vdev.senseid));
> >>       /* run sense id command */
> >> -    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid))) {
> >> +    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid),
> >> +                true)) {
> >>           return false;
> >>       }
> >>       if (vdev.senseid.cu_type == 0x3832) {  
> > 
> > Can't you use the new routine for obtaining the cu type here?
> >   
> 
> cu_type only returns the control unit type. This code goes on to look at the model number 
> as well. In hind sight, I could have noticed this and simply structured my code to return 
> the whole sense_id data structure. I'm not against making this change, but things seem 
> pretty clean as they are. :)

I find having two different places that do SENSE_ID a bit odd :)

But no really strong opinion here; I'll happily leave the decision to
the boot code maintainers.
diff mbox series

Patch

diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
index aa9da72..711daf5 100644
--- a/pc-bios/s390-ccw/virtio.c
+++ b/pc-bios/s390-ccw/virtio.c
@@ -14,6 +14,7 @@ 
 #include "virtio.h"
 #include "virtio-scsi.h"
 #include "bswap.h"
+#include "helper.h"
 
 #define VRING_WAIT_REPLY_TIMEOUT 30
 
@@ -89,33 +90,20 @@  int drain_irqs(SubChannelId schid)
     }
 }
 
-static int run_ccw(VDev *vdev, int cmd, void *ptr, int len)
+static int run_ccw(VDev *vdev, int cmd, void *ptr, int len, bool sli)
 {
     Ccw1 ccw = {};
-    CmdOrb orb = {};
-    int r;
-
-    enable_subchannel(vdev->schid);
-
-    /* start subchannel command */
-    orb.fmt = 1;
-    orb.cpa = (u32)(long)&ccw;
-    orb.lpm = 0x80;
 
     ccw.cmd_code = cmd;
     ccw.cda = (long)ptr;
     ccw.count = len;
 
-    r = ssch(vdev->schid, &orb);
-    /*
-     * XXX Wait until device is done processing the CCW. For now we can
-     *     assume that a simple tsch will have finished the CCW processing,
-     *     but the architecture allows for asynchronous operation
-     */
-    if (!r) {
-        r = drain_irqs(vdev->schid);
+    if (sli) {
+        ccw.flags |= CCW_FLAG_SLI;
     }
-    return r;
+
+    enable_subchannel(vdev->schid);
+    return do_cio(vdev->schid, ptr2u32(&ccw), CCW_FMT1);
 }
 
 static void vring_init(VRing *vr, VqInfo *info)
@@ -257,7 +245,7 @@  void virtio_setup_ccw(VDev *vdev)
     vdev->config.blk.blk_size = 0; /* mark "illegal" - setup started... */
     vdev->guessed_disk_nature = VIRTIO_GDN_NONE;
 
-    run_ccw(vdev, CCW_CMD_VDEV_RESET, NULL, 0);
+    run_ccw(vdev, CCW_CMD_VDEV_RESET, NULL, 0, false);
 
     switch (vdev->senseid.cu_model) {
     case VIRTIO_ID_NET:
@@ -278,18 +266,19 @@  void virtio_setup_ccw(VDev *vdev)
     default:
         panic("Unsupported virtio device\n");
     }
-    IPL_assert(run_ccw(vdev, CCW_CMD_READ_CONF, &vdev->config, cfg_size) == 0,
-               "Could not get block device configuration");
+    IPL_assert(
+        run_ccw(vdev, CCW_CMD_READ_CONF, &vdev->config, cfg_size, false) == 0,
+       "Could not get block device configuration");
 
     /* Feature negotiation */
     for (i = 0; i < ARRAY_SIZE(vdev->guest_features); i++) {
         feats.features = 0;
         feats.index = i;
-        rc = run_ccw(vdev, CCW_CMD_READ_FEAT, &feats, sizeof(feats));
+        rc = run_ccw(vdev, CCW_CMD_READ_FEAT, &feats, sizeof(feats), false);
         IPL_assert(rc == 0, "Could not get features bits");
         vdev->guest_features[i] &= bswap32(feats.features);
         feats.features = bswap32(vdev->guest_features[i]);
-        rc = run_ccw(vdev, CCW_CMD_WRITE_FEAT, &feats, sizeof(feats));
+        rc = run_ccw(vdev, CCW_CMD_WRITE_FEAT, &feats, sizeof(feats), false);
         IPL_assert(rc == 0, "Could not set features bits");
     }
 
@@ -306,16 +295,17 @@  void virtio_setup_ccw(VDev *vdev)
         };
 
         IPL_assert(
-            run_ccw(vdev, CCW_CMD_READ_VQ_CONF, &config, sizeof(config)) == 0,
+            run_ccw(vdev, CCW_CMD_READ_VQ_CONF, &config, sizeof(config), false) == 0,
             "Could not get block device VQ configuration");
         info.num = config.num;
         vring_init(&vdev->vrings[i], &info);
         vdev->vrings[i].schid = vdev->schid;
-        IPL_assert(run_ccw(vdev, CCW_CMD_SET_VQ, &info, sizeof(info)) == 0,
-                   "Cannot set VQ info");
+        IPL_assert(
+            run_ccw(vdev, CCW_CMD_SET_VQ, &info, sizeof(info), false) == 0,
+            "Cannot set VQ info");
     }
     IPL_assert(
-        run_ccw(vdev, CCW_CMD_WRITE_STATUS, &status, sizeof(status)) == 0,
+        run_ccw(vdev, CCW_CMD_WRITE_STATUS, &status, sizeof(status), false) == 0,
         "Could not write status to host");
 }
 
@@ -324,7 +314,8 @@  bool virtio_is_supported(SubChannelId schid)
     vdev.schid = schid;
     memset(&vdev.senseid, 0, sizeof(vdev.senseid));
     /* run sense id command */
-    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid))) {
+    if (run_ccw(&vdev, CCW_CMD_SENSE_ID, &vdev.senseid, sizeof(vdev.senseid),
+                true)) {
         return false;
     }
     if (vdev.senseid.cu_type == 0x3832) {