iommu sg merging: sparc64: make iommu respect the segment size limits
This patch makes iommu respect segment size limits when merging sg
lists.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/sparc64/kernel/iommu_common.c b/arch/sparc64/kernel/iommu_common.c
index efd5dff..72a4acf 100644
--- a/arch/sparc64/kernel/iommu_common.c
+++ b/arch/sparc64/kernel/iommu_common.c
@@ -4,6 +4,7 @@
* Copyright (C) 1999 David S. Miller (davem@redhat.com)
*/
+#include <linux/dma-mapping.h>
#include "iommu_common.h"
/* You are _strongly_ advised to enable the following debugging code
@@ -201,21 +202,24 @@
}
#endif
-unsigned long prepare_sg(struct scatterlist *sg, int nents)
+unsigned long prepare_sg(struct device *dev, struct scatterlist *sg, int nents)
{
struct scatterlist *dma_sg = sg;
unsigned long prev;
u32 dent_addr, dent_len;
+ unsigned int max_seg_size;
prev = (unsigned long) sg_virt(sg);
prev += (unsigned long) (dent_len = sg->length);
dent_addr = (u32) ((unsigned long)(sg_virt(sg)) & (IO_PAGE_SIZE - 1UL));
+ max_seg_size = dma_get_max_seg_size(dev);
while (--nents) {
unsigned long addr;
sg = sg_next(sg);
addr = (unsigned long) sg_virt(sg);
- if (! VCONTIG(prev, addr)) {
+ if (! VCONTIG(prev, addr) ||
+ dent_len + sg->length > max_seg_size) {
dma_sg->dma_address = dent_addr;
dma_sg->dma_length = dent_len;
dma_sg = sg_next(dma_sg);