On Thu, 2006-05-18 at 22:07 -0700, Randy.Dunlap wrote: > From: Randy Dunlap <rdunlap@xxxxxxxxxxxx> > > ppa cannot handle highmem pages, and like imm, which already has > this patch, the device is slow, so performance is not a big issue, > so just force pages to be in low memory (hence mapped). > > Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxx> > --- > drivers/scsi/ppa.c | 4 ++++ > 1 files changed, 4 insertions(+) > > --- linux-2.6.17-rc4.orig/drivers/scsi/ppa.c > +++ linux-2.6.17-rc4/drivers/scsi/ppa.c > @@ -997,6 +997,10 @@ static struct scsi_host_template ppa_tem > .cmd_per_lun = 1, > .use_clustering = ENABLE_CLUSTERING, > .can_queue = 1, > + .unchecked_isa_dma = 1, /* ppa cannot deal with highmem, so > + * this is an easy trick to ensure > + * all io pages for this host reside > + * in low memory */ This is the wrong thing to do. You'll force all allocations for this device to go through ZONE_DMA, which is a horrifically constrained resource at 16MB. If it can take anything in lowmem because the driver is unconverted, then you want it to specify BLK_BOUNCE_HIGH as the queue limit. James - : 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
