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[PATCH 13/31] sparc/ldc: handle page-less SG entries

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Use

    sg_phys(sg) & PAGE_MASK

instead of

    page_to_pfn(sg_page(sg)) << PAGE_SHIFT

to get at the page-aligned physical address ofa SG entry, so that
we don't require a page backing for SG entries.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/sparc/kernel/ldc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/sparc/kernel/ldc.c b/arch/sparc/kernel/ldc.c
index 1ae5eb1..0a29974 100644
--- a/arch/sparc/kernel/ldc.c
+++ b/arch/sparc/kernel/ldc.c
@@ -2051,7 +2051,7 @@ static void fill_cookies(struct cookie_state *sp, unsigned long pa,
 
 static int sg_count_one(struct scatterlist *sg)
 {
-	unsigned long base = page_to_pfn(sg_page(sg)) << PAGE_SHIFT;
+	unsigned long base = sg_phys(sg) & PAGE_MASK;
 	long len = sg->length;
 
 	if ((sg->offset | len) & (8UL - 1))
@@ -2114,7 +2114,7 @@ int ldc_map_sg(struct ldc_channel *lp,
 	state.nc = 0;
 
 	for_each_sg(sg, s, num_sg, i) {
-		fill_cookies(&state, page_to_pfn(sg_page(s)) << PAGE_SHIFT,
+		fill_cookies(&state, sg_phys(s) & PAGE_MASK,
 			     s->offset, s->length);
 	}
 
-- 
1.9.1

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[PATCH 13/31] sparc/ldc: handle page-less SG entries Christoph Hellwig <hch@lst.de> - 2015-08-12 09:20 +0200

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