diff options
Diffstat (limited to 'include/linux/uio.h')
-rw-r--r-- | include/linux/uio.h | 51 |
1 files changed, 37 insertions, 14 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h index 199bcc34241..e2231e47cec 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -19,11 +19,21 @@ struct kvec { size_t iov_len; }; +enum { + ITER_IOVEC = 0, + ITER_KVEC = 2, + ITER_BVEC = 4, +}; + struct iov_iter { - const struct iovec *iov; - unsigned long nr_segs; + int type; size_t iov_offset; size_t count; + union { + const struct iovec *iov; + const struct bio_vec *bvec; + }; + unsigned long nr_segs; }; /* @@ -53,6 +63,7 @@ static inline struct iovec iov_iter_iovec(const struct iov_iter *iter) } #define iov_for_each(iov, iter, start) \ + if (!((start).type & ITER_BVEC)) \ for (iter = (start); \ (iter).count && \ ((iov = iov_iter_iovec(&(iter))), 1); \ @@ -62,32 +73,44 @@ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to); size_t iov_iter_copy_from_user_atomic(struct page *page, struct iov_iter *i, unsigned long offset, size_t bytes); -size_t iov_iter_copy_from_user(struct page *page, - struct iov_iter *i, unsigned long offset, size_t bytes); void iov_iter_advance(struct iov_iter *i, size_t bytes); int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes); size_t iov_iter_single_seg_count(const struct iov_iter *i); size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes, struct iov_iter *i); +size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes, + struct iov_iter *i); +unsigned long iov_iter_alignment(const struct iov_iter *i); +void iov_iter_init(struct iov_iter *i, int direction, const struct iovec *iov, + unsigned long nr_segs, size_t count); +ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages, + size_t maxsize, size_t *start); +ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages, + size_t maxsize, size_t *start); +int iov_iter_npages(const struct iov_iter *i, int maxpages); -static inline void iov_iter_init(struct iov_iter *i, - const struct iovec *iov, unsigned long nr_segs, - size_t count, size_t written) +static inline size_t iov_iter_count(struct iov_iter *i) { - i->iov = iov; - i->nr_segs = nr_segs; - i->iov_offset = 0; - i->count = count + written; + return i->count; +} - iov_iter_advance(i, written); +static inline void iov_iter_truncate(struct iov_iter *i, size_t count) +{ + if (i->count > count) + i->count = count; } -static inline size_t iov_iter_count(struct iov_iter *i) +/* + * reexpand a previously truncated iterator; count must be no more than how much + * we had shrunk it. + */ +static inline void iov_iter_reexpand(struct iov_iter *i, size_t count) { - return i->count; + i->count = count; } int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len); + #endif |