Re: [BK PATCH] SCSI -rc fixes for 2.6.10-rc3

From: Jens Axboe
Date: Fri Dec 10 2004 - 15:14:26 EST


On Thu, Dec 09 2004, James Bottomley wrote:
> This one is another set of small driver fixes
>
> It is available from:

Here is one more. Currently imm uses page_address() which can crash on
highmem. It's not directly doable to map the pages properly, at least
not without changing some code. In lack of a ->bounce_highio member in
the scsi host template, just set ->unchecked_isa_dma which will just
bounce everything for us. imm isn't performance critical by any stretch
of the imagination, so...

Usually I'd not encourage such a silly hack, but in lack of hardware for
testing (who has it??), this should suffice as it is obviously correct.

Signed-off-by: Jens Axboe <axboe@xxxxxxx>

===== drivers/scsi/imm.c 1.39 vs edited =====
--- 1.39/drivers/scsi/imm.c 2004-08-25 01:09:03 +02:00
+++ edited/drivers/scsi/imm.c 2004-12-10 21:07:29 +01:00
@@ -1140,6 +1140,10 @@
.use_clustering = ENABLE_CLUSTERING,
.can_queue = 1,
.slave_alloc = imm_adjust_queue,
+ .unchecked_isa_dma = 1, /* imm cannot deal with highmem, so
+ * this is an easy trick to ensure
+ * all io pages for this host reside
+ * in low memory */
};

/***************************************************************************


--
Jens Axboe

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