Re: [PATCH 8/12] x86-64: update iommu/dma mapping functions to sg helpers

[Benny Halevy <bhalevy@panasas.com>]

Jens Axboe wrote:
> On Thu, May 10 2007, Benny Halevy wrote:
>> @@ -411,12 +406,13 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
>>  			   boundary and the new one doesn't have an offset. */
>>  			if (!iommu_merge || !nextneed || !need || s->offset ||
>>  			    (ps->offset + ps->length) % PAGE_SIZE) { 
>> -				if (dma_map_cont(sg, start, i, sg+out, pages,
>> -						 need) < 0)
>> +				if (dma_map_cont(start_sg, i - start, sg+out,
>> +						  pages, need) < 0)
>>  					goto error;
>>  				out++;
>>  				pages = 0;
>> -				start = i;	
>> +				start = i;
>> +				start_sg = s;
>>  			}
>>  		}
>>  
>> @@ -424,7 +420,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
>>  		pages += to_pages(s->offset, s->length);
>>  		ps = s;
>>  	}
>> -	if (dma_map_cont(sg, start, i, sg+out, pages, need) < 0)
>> +	if (dma_map_cont(start_sg, i - start, sg+out, pages, need) < 0)
>>  		goto error;
>>  	out++;
>>  	flush_gart();
> 
> Your patch is (very) buggy, the whole premise of doing chained sg
> entries makes sg + int illegal!
> 

You're right.  I'll send a fix asap.

Benny

-- 
Benny Halevy
Software Architect
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