diff options
| author | FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | 2008-03-18 00:15:03 +0900 |
|---|---|---|
| committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2008-04-07 12:15:45 -0500 |
| commit | b1adaf65ba0398c9a1adc8f3a274533165a4df61 (patch) | |
| tree | 70c6c5944eb978c6eff55eab1e1b1df7049477ec /include/linux/scatterlist.h | |
| parent | 78b4b05db57b04b3ed17dc71259bf1402c04abfa (diff) | |
[SCSI] block: add sg buffer copy helper functions
This patch adds new three helper functions to copy data between an SG
list and a linear buffer.
- sg_copy_from_buffer copies data from linear buffer to an SG list
- sg_copy_to_buffer copies data from an SG list to a linear buffer
When the APIs copy data from a linear buffer to an SG list,
flush_kernel_dcache_page is called. It's not necessary for everyone
but it's a no-op on most architectures and in general the API is not
used in performance critical path.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'include/linux/scatterlist.h')
| -rw-r--r-- | include/linux/scatterlist.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h index a3d567a974e..71fc8136004 100644 --- a/include/linux/scatterlist.h +++ b/include/linux/scatterlist.h @@ -213,6 +213,11 @@ int __sg_alloc_table(struct sg_table *, unsigned int, unsigned int, gfp_t, sg_alloc_fn *); int sg_alloc_table(struct sg_table *, unsigned int, gfp_t); +size_t sg_copy_from_buffer(struct scatterlist *sgl, unsigned int nents, + void *buf, size_t buflen); +size_t sg_copy_to_buffer(struct scatterlist *sgl, unsigned int nents, + void *buf, size_t buflen); + /* * Maximum number of entries that will be allocated in one piece, if * a list larger than this is required then chaining will be utilized. |