[PATCH] yaboot: enable boot from iscsi target via ethernet devices on js20.

[Doug Maxey]

On Tue, 16 May 2006 15:40:30 CDT, Doug Maxey wrote:
>
>On Tue, 16 May 2006 16:20:47 EDT, Paul Nasrat wrote:
>>On Fri, 2006-04-28 at 01:05 -0500, Doug Maxey wrote:
>>> Certain levels of JS20 firmware will allow the system to boot from an
>>> iscsi target.  System OFW accomplishes this by setting up a virtual
>>> disk device with parameters.  These parameters, when passed back to
>>> OFW by yaboot, directs the FW to use virtual device over the ethernet
>>> port that will then access iscsi target as a block device.  This patch
>>> extracts those parameters from the property of the virtual device and
>>> passes them back to OFW to indicate the kernel is to be retrieved via
>>> the iscsi protocol.
>>> 
>>> Signed-off-by: Doug Maxey <dwm at austin.ibm.com>
>>
>>Sorry for the delay in getting back to you - a few initial questions:
>
>np.  been on vacation the last 10 days.  Switzerland is nice, and Milan 
>is cool. :)
>
>>
>>> diff --git a/second/file.c b/second/file.c
>>
>>> @@ -185,16 +188,45 @@ parse_device_path(char *imagepath, char 
>>>  
>>>       if (!imagepath)
>>>  	  return 0;
>>> +
>>> +      /*
>>> +       * Do preliminary checking for an iscsi device; it may appear as
>>> +       * pure a network device (device_type == "network") if this is
>>> +       * ISWI.  This is the case on IBM systems doing an iscsi OFW
>>> +       * boot.
>>> +       */
>>> +     if (strstr(imagepath, ",iscsi"))
>>
>>Is the , always guaranteed to be there - eg if I have boot
>>eth1:iscsi,ISCSIARGS  won't this check fail.
>
>Yes, with the above command line this would fail. 
>
>My point of reference are the bindings that we cannot yet talk about 
>here, yet.  The device args would always be followed by a comma.  I suppose 
>that we could just reference the string "iscsi", but then some wag 
>would want to create some other property that included "iscsi" as a 
>substring.  Maybe append a comma?

Any preferences on this?  

I have another, more radical solution.  

Adding a parser that understands the full device path and that can 
return the elements neatly packaged.  Film at 11. 

>
>
>>
>>> diff --git a/second/prom.c b/second/prom.c
>>> index 5ec06b8..9bc5415 100644
>>> --- a/second/prom.c
>>> +++ b/second/prom.c
>>> @@ -174,6 +174,9 @@ prom_get_devtype (char *device)
>>>       int        result;
>>>       char       tmp[64];
>>>  
>>> +     if (strstr(device, ",iscsi"))
>>> +	  device = strcpy(tmp, "/vdevice/gscsi/disk");
>>> +
>>
>>Ditto here.
>
>likewise.  Maybe make it a #define so it would be common.
>
>>
>>Paul
>>

++doug