[PATCH 3/5] add sg segment limitation info to device structure

FUJITA Tomonori
2007-09-26T08:58:36Z

iommu code merges sg segments without considering lld's sg segment
restrictions. iommu code can't access to the limitations because they
are in request_queue. This patch adds max_segment_size to device
structure. seg_boundary_mask will be added too later.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
---
include/linux/device.h | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/include/linux/device.h b/include/linux/device.h
index 3a38d1f..8046b60 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -443,6 +443,13 @@ struct device {

struct dma_coherent_mem *dma_mem; /* internal for coherent mem
override */
+
+ /*
+ * a low level driver may set these to teach IOMMU code about
+ * sg limitations.
+ */
+ unsigned int max_segment_size;
+
/* arch specific additions */
struct dev_archdata archdata;

--
1.5.2.4