From 2a1bf8f93b33992bb0457512b28d046e279bbd7e Mon Sep 17 00:00:00 2001 From: Dave Gordon Date: Tue, 30 Jun 2015 14:58:54 -0700 Subject: [PATCH] lib/scatterlist: mark input buffer parameters as 'const' The 'buf' parameter of sg(p)copy_from_buffer() can and should be const-qualified, although because of the shared implementation of _to_buffer() and _from_buffer(), we have to cast this away internally. This means that callers who have a 'const' buffer containing the data to be copied to the sg-list no longer have to cast away the const-ness themselves. It also enables improved coverage by code analysis tools. Signed-off-by: Dave Gordon Cc: Akinobu Mita Cc: "Martin K. Petersen" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/scatterlist.h | 4 ++-- lib/scatterlist.c | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h index 50a8486..505d048 100644 --- a/include/linux/scatterlist.h +++ b/include/linux/scatterlist.h @@ -266,12 +266,12 @@ int sg_alloc_table_from_pages(struct sg_table *sgt, gfp_t gfp_mask); size_t sg_copy_from_buffer(struct scatterlist *sgl, unsigned int nents, - void *buf, size_t buflen); + const void *buf, size_t buflen); size_t sg_copy_to_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, size_t buflen); size_t sg_pcopy_from_buffer(struct scatterlist *sgl, unsigned int nents, - void *buf, size_t buflen, off_t skip); + const void *buf, size_t buflen, off_t skip); size_t sg_pcopy_to_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, size_t buflen, off_t skip); diff --git a/lib/scatterlist.c b/lib/scatterlist.c index 965c36e..317b62c 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -701,9 +701,9 @@ static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, * **/ size_t sg_copy_from_buffer(struct scatterlist *sgl, unsigned int nents, - void *buf, size_t buflen) + const void *buf, size_t buflen) { - return sg_copy_buffer(sgl, nents, buf, buflen, 0, false); + return sg_copy_buffer(sgl, nents, (void *)buf, buflen, 0, false); } EXPORT_SYMBOL(sg_copy_from_buffer); @@ -736,9 +736,9 @@ EXPORT_SYMBOL(sg_copy_to_buffer); * **/ size_t sg_pcopy_from_buffer(struct scatterlist *sgl, unsigned int nents, - void *buf, size_t buflen, off_t skip) + const void *buf, size_t buflen, off_t skip) { - return sg_copy_buffer(sgl, nents, buf, buflen, skip, false); + return sg_copy_buffer(sgl, nents, (void *)buf, buflen, skip, false); } EXPORT_SYMBOL(sg_pcopy_from_buffer); -- 2.7.4