From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Date: Wed, 17 Oct 2007 08:51:20 +0000 (+0200)
Subject: IA64: iommu uses sg_next with an invalid sg element
X-Git-Tag: v2.6.24-rc1~490^2~4
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bdb02504f473be6a785741093913ea2acd05626f;p=linux-2.6

IA64: iommu uses sg_next with an invalid sg element

sg list elements might not be continuous.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---

diff --git a/arch/ia64/hp/common/sba_iommu.c b/arch/ia64/hp/common/sba_iommu.c
index 4338f4123f..3c95f4184b 100644
--- a/arch/ia64/hp/common/sba_iommu.c
+++ b/arch/ia64/hp/common/sba_iommu.c
@@ -1179,7 +1179,6 @@ sba_fill_pdir(
 	u64 *pdirp = NULL;
 	unsigned long dma_offset = 0;
 
-	dma_sg--;
 	while (nents-- > 0) {
 		int     cnt = startsg->dma_length;
 		startsg->dma_length = 0;
@@ -1201,7 +1200,8 @@ sba_fill_pdir(
 			u32 pide = startsg->dma_address & ~PIDE_FLAG;
 			dma_offset = (unsigned long) pide & ~iovp_mask;
 			startsg->dma_address = 0;
-			dma_sg = sg_next(dma_sg);
+			if (n_mappings)
+				dma_sg = sg_next(dma_sg);
 			dma_sg->dma_address = pide | ioc->ibase;
 			pdirp = &(ioc->pdir_base[pide >> iovp_shift]);
 			n_mappings++;