A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-28 02:32:09 -04:00
Code Issues Projects Releases Packages Wiki Activity

DMA-API.txt: fix description of pci_map_sg/dma_map_sg scatterlists handling

Browse source 
- pci_map_sg/dma_map_sg are used with a scatter gather list that doesn't
  come from the block layer (e.g.  some network drivers do).

- how IOMMUs merge adjacent elements of the scatter/gather list is
  independent of how the block layer determines sees elements.

Signed-off-by: FUJITA Tomonori <[email protected]>
Cc: James Bottomley <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Jens Axboe <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
FUJITA Tomonori 2008-12-01 13:14:01 -08:00 • committed by Linus Torvalds
commit 1d678f365d
1 changed files with 3 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

8
Documentation/DMA-API.txt
View file

@ -316,12 +316,10 @@ reduce current DMA mapping usage or delay and try again later).
pci_map_sg(struct pci_dev *hwdev, struct scatterlist *sg,
int nents, int direction)
Maps a scatter gather list from the block layer.
Returns: the number of physical segments mapped (this may be shorter
than <nents> passed in if the block layer determines that some
elements of the scatter/gather list are physically adjacent and thus
may be mapped with a single entry).
than <nents> passed in if some elements of the scatter/gather list are
physically or virtually adjacent and an IOMMU maps them with a single
entry).
Please note that the sg cannot be mapped again if it has been mapped once.
The mapping process is allowed to destroy information in the sg.