Re: [PATCH v4 2/2] xen/block: add multi-page ring support

[Bob Liu <bob.liu@oracle.com>]

On 05/21/2015 07:22 PM, Roger Pau Monné wrote:
> El 20/05/15 a les 15.10, Bob Liu ha escrit:
...
>> +	} else {
>> +		unsigned int i;
>> +
>> +		if (ring_page_order > xen_blkif_max_ring_order) {
>> +			err = -EINVAL;
>> +			xenbus_dev_fatal(dev, err, "%s/request %d ring page order exceed max:%d",
>> +					 dev->otherend, ring_page_order, xen_blkif_max_ring_order);
>> +			return err;
>> +		}
>> +
>> +		nr_grefs = 1 << ring_page_order;
>> +		for (i = 0; i < nr_grefs; i++) {
>> +			char ring_ref_name[RINGREF_NAME_LEN];
>> +
>> +			snprintf(ring_ref_name, sizeof(ring_ref_name), "ring-ref%u", i);
>                                                 ^ RINGREF_NAME_LEN
>> +			err = xenbus_scanf(XBT_NIL, dev->otherend,
>> +					   ring_ref_name, "%u", &ring_ref[i]);
> 
> No need to split lines unless they are > 100 chars (here and elsewhere).
> 

Not 82 chars?

>> diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
>> index 88e23fd..3d1c6fb 100644
>> --- a/drivers/block/xen-blkfront.c
>> +++ b/drivers/block/xen-blkfront.c
>> @@ -98,7 +98,17 @@ static unsigned int xen_blkif_max_segments = 32;
>>  module_param_named(max, xen_blkif_max_segments, int, S_IRUGO);
>>  MODULE_PARM_DESC(max, "Maximum amount of segments in indirect requests (default is 32)");
>>  
>> -#define BLK_RING_SIZE __CONST_RING_SIZE(blkif, PAGE_SIZE)
>> +static unsigned int xen_blkif_max_ring_order;
>> +module_param_named(max_ring_page_order, xen_blkif_max_ring_order, int, S_IRUGO);
>> +MODULE_PARM_DESC(max_ring_page_order, "Maximum order of pages to be used as the ring");
>> +
>> +#define BLK_RING_SIZE __CONST_RING_SIZE(blkif, PAGE_SIZE * info->nr_ring_pages)
> 
> Didn't we agreed that this macro should take a explicit info parameter?
> 

Do you mean define like this?
#define BLK_RING_SIZE(info) __CONST_RING_SIZE(blkif, PAGE_SIZE * info->nr_ring_pages)

Thanks,
-Bob