diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/crypto/scatterwalk.h | 69 |
1 files changed, 63 insertions, 6 deletions
diff --git a/include/crypto/scatterwalk.h b/include/crypto/scatterwalk.h index 5c7765f601e0..8e83c43016c9 100644 --- a/include/crypto/scatterwalk.h +++ b/include/crypto/scatterwalk.h @@ -64,12 +64,6 @@ static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk, return min(nbytes, scatterwalk_pagelen(walk)); } -static inline void scatterwalk_advance(struct scatter_walk *walk, - unsigned int nbytes) -{ - walk->offset += nbytes; -} - static inline struct page *scatterwalk_page(struct scatter_walk *walk) { return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT); @@ -86,6 +80,24 @@ static inline void *scatterwalk_map(struct scatter_walk *walk) offset_in_page(walk->offset); } +/** + * scatterwalk_next() - Get the next data buffer in a scatterlist walk + * @walk: the scatter_walk + * @total: the total number of bytes remaining, > 0 + * @nbytes_ret: (out) the next number of bytes available, <= @total + * + * Return: A virtual address for the next segment of data from the scatterlist. + * The caller must call scatterwalk_done_src() or scatterwalk_done_dst() + * when it is done using this virtual address. + */ +static inline void *scatterwalk_next(struct scatter_walk *walk, + unsigned int total, + unsigned int *nbytes_ret) +{ + *nbytes_ret = scatterwalk_clamp(walk, total); + return scatterwalk_map(walk); +} + static inline void scatterwalk_pagedone(struct scatter_walk *walk, int out, unsigned int more) { @@ -108,6 +120,51 @@ static inline void scatterwalk_done(struct scatter_walk *walk, int out, scatterwalk_pagedone(walk, out, more); } +static inline void scatterwalk_advance(struct scatter_walk *walk, + unsigned int nbytes) +{ + walk->offset += nbytes; +} + +/** + * scatterwalk_done_src() - Finish one step of a walk of source scatterlist + * @walk: the scatter_walk + * @vaddr: the address returned by scatterwalk_next() + * @nbytes: the number of bytes processed this step, less than or equal to the + * number of bytes that scatterwalk_next() returned. + * + * Use this if the @vaddr was not written to, i.e. it is source data. + */ +static inline void scatterwalk_done_src(struct scatter_walk *walk, + const void *vaddr, unsigned int nbytes) +{ + scatterwalk_unmap((void *)vaddr); + scatterwalk_advance(walk, nbytes); +} + +/** + * scatterwalk_done_dst() - Finish one step of a walk of destination scatterlist + * @walk: the scatter_walk + * @vaddr: the address returned by scatterwalk_next() + * @nbytes: the number of bytes processed this step, less than or equal to the + * number of bytes that scatterwalk_next() returned. + * + * Use this if the @vaddr may have been written to, i.e. it is destination data. + */ +static inline void scatterwalk_done_dst(struct scatter_walk *walk, + void *vaddr, unsigned int nbytes) +{ + scatterwalk_unmap(vaddr); + /* + * Explicitly check ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE instead of just + * relying on flush_dcache_page() being a no-op when not implemented, + * since otherwise the BUG_ON in sg_page() does not get optimized out. + */ + if (ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE) + flush_dcache_page(scatterwalk_page(walk)); + scatterwalk_advance(walk, nbytes); +} + void scatterwalk_skip(struct scatter_walk *walk, unsigned int nbytes); void scatterwalk_copychunks(void *buf, struct scatter_walk *walk, |