On Mon, Feb 25, 2008 at 06:48:28AM -0800, James Bottomley wrote: > On Mon, 2008-02-25 at 00:35 +0100, Andi Kleen wrote: > > sense buffers are something that still needs to be explicitely > > bounced in the scsi layer. Instead of using the global unchecked_isa_dma > > flag define a special fine grained mask for this. > > > > I decided to use a full dma mask because that is most useful for some future > > infrastructure work I'm doing. > > Why do we need a separate mask? Why can't we just use the device > dma_mask?
First a lot of drivers don't need it because they handle the sense buffers without DMA. So if we just used a device mask we would either do unnecessary work for those or require a special sense buffer mask in the device (which wouldn't belong into the device layer) Then there isn't really a device anywhere in these drivers and I didn't plan to rewrite them to add one. So just having a SCSI specific sense buffer mask seemed best. It is only set when a ISA driver actually does sense buffer DMA, which is only true in a handful of drivers. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
