On Tue, 07 Aug 2007 12:13:41 -0500 Mike Christie <michaelc@xxxxxxxxxxx> wrote: > FUJITA Tomonori wrote: > > Allocating 64K contiguous memory is not good so the next thing to do > > is converting sg to use the sg chaining support fully. Or it might be > > For LLDs like aic7xxx, I think we are stuck with a small > scsi_host_template->sg_tablesize, so to continue to get large requests > like before will we have to still allocate large segments? No. sg.c has: sizeof(struct scatterlist) * min(q->max_hw_segments, q->max_phys_segments) If a lld has small max_hw_segments, it doesn't allocate big contiguous memory. > Is block/scsi_ioctl.c converted to sg chaining in any tree yet? Is that > in your tree or one of Jen's branches. block/scsi_ioctl.c uses the standard block layer functions, there is nothing to convert in it. sglist doesn't change the standard block layer functions much since it doesn't allocate sg list. It changes only blk_rq_map_sg. Now only scsi-ml is changed to allocate chaining sg list properly. Others like cciss are not converted yet, I think. It might make sense to have the standard block layer functions to allocate chaining sg list properly. So we could convert to potential consumers (scsi-ml, sg, ccisss, etc) use them though I'm not sure how many non scsi-ml needs chaining sg list. - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
