From: FUJITA Tomonori Date: Mon, 8 Mar 2010 08:11:07 +0000 (+0100) Subject: Documentation: fix block/biodoc.txt dma mapping description X-Git-Tag: firefly_0821_release~9833^2~2371^2~33 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c2282adbdea3548ae0271c1b1b2deec5f56ad224;p=firefly-linux-kernel-4.4.55.git Documentation: fix block/biodoc.txt dma mapping description - 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 Signed-off-by: Jens Axboe --- diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt index 6fab97ea7e6b..508b5b2b0289 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,