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Subject[PATCH] Documentation: fix block/biodoc.txt dma mapping description
From
- It looks incorrect to use blk_rq_map_sg with pci_map_page here about
DMA mappings. dma_map_sg?

- better to use dma_map_page instead of pci_map_page.
http://marc.info/?l=linux-kernel&m=126596737604808&w=2

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
---
Documentation/block/biodoc.txt | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index 6fab97e..508b5b2 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -1162,8 +1162,8 @@ where a driver received a request ala this before:

As mentioned, there is no virtual mapping of a bio. For DMA, this is
not a problem as the driver probably never will need a virtual mapping.
-Instead it needs a bus mapping (pci_map_page for a single segment or
-use blk_rq_map_sg for scatter gather) to be able to ship it to the driver. For
+Instead it needs a bus mapping (dma_map_page for a single segment or
+use dma_map_sg for scatter gather) to be able to ship it to the driver. For
PIO drivers (or drivers that need to revert to PIO transfer once in a
while (IDE for example)), where the CPU is doing the actual data
transfer a virtual mapping is needed. If the driver supports highmem I/O,
--
1.6.5


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