--- zzzz-none-000/linux-3.10.107/include/linux/uio.h 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/include/linux/uio.h 2021-02-04 17:41:59.000000000 +0000 @@ -9,14 +9,34 @@ #ifndef __LINUX_UIO_H #define __LINUX_UIO_H +#include #include +struct page; struct kvec { void *iov_base; /* and that should *never* hold a userland pointer */ size_t iov_len; }; +enum { + ITER_IOVEC = 0, + ITER_KVEC = 2, + ITER_BVEC = 4, +}; + +struct iov_iter { + int type; + size_t iov_offset; + size_t count; + union { + const struct iovec *iov; + const struct kvec *kvec; + const struct bio_vec *bvec; + }; + unsigned long nr_segs; +}; + /* * Total number of bytes covered by an iovec. * @@ -34,8 +54,112 @@ return ret; } +static inline struct iovec iov_iter_iovec(const struct iov_iter *iter) +{ + return (struct iovec) { + .iov_base = iter->iov->iov_base + iter->iov_offset, + .iov_len = min(iter->count, + iter->iov->iov_len - iter->iov_offset), + }; +} + +#define iov_for_each(iov, iter, start) \ + if (!((start).type & ITER_BVEC)) \ + for (iter = (start); \ + (iter).count && \ + ((iov = iov_iter_iovec(&(iter))), 1); \ + iov_iter_advance(&(iter), (iov).iov_len)) + unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to); -int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); -int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len); +size_t iov_iter_copy_from_user_atomic(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); +#define iov_iter_fault_in_multipages_readable iov_iter_fault_in_readable +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); +size_t copy_to_iter(void *addr, size_t bytes, struct iov_iter *i); +size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i); +size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i); +size_t iov_iter_zero(size_t bytes, struct iov_iter *); +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); +void iov_iter_kvec(struct iov_iter *i, int direction, const struct kvec *kvec, + unsigned long nr_segs, size_t count); +void iov_iter_bvec(struct iov_iter *i, int direction, const struct bio_vec *bvec, + unsigned long nr_segs, size_t count); +ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages, + size_t maxsize, unsigned maxpages, 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); + +const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags); + +static inline size_t iov_iter_count(const struct iov_iter *i) +{ + return i->count; +} + +static inline bool iter_is_iovec(const struct iov_iter *i) +{ + return !(i->type & (ITER_BVEC | ITER_KVEC)); +} + +/* + * Get one of READ or WRITE out of iter->type without any other flags OR'd in + * with it. + * + * The ?: is just for type safety. + */ +#define iov_iter_rw(i) ((0 ? (struct iov_iter *)0 : (i))->type & RW_MASK) + +/* + * Cap the iov_iter by given limit; note that the second argument is + * *not* the new size - it's upper limit for such. Passing it a value + * greater than the amount of data in iov_iter is fine - it'll just do + * nothing in that case. + */ +static inline void iov_iter_truncate(struct iov_iter *i, u64 count) +{ + /* + * count doesn't have to fit in size_t - comparison extends both + * operands to u64 here and any value that would be truncated by + * conversion in assignement is by definition greater than all + * values of size_t, including old i->count. + */ + if (i->count > count) + i->count = count; +} + +/* + * 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) +{ + i->count = count; +} +size_t csum_and_copy_to_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i); +size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i); + +int import_iovec(int type, const struct iovec __user * uvector, + unsigned nr_segs, unsigned fast_segs, + struct iovec **iov, struct iov_iter *i); + +#ifdef CONFIG_COMPAT +struct compat_iovec; +int compat_import_iovec(int type, const struct compat_iovec __user * uvector, + unsigned nr_segs, unsigned fast_segs, + struct iovec **iov, struct iov_iter *i); +#endif + +int import_single_range(int type, void __user *buf, size_t len, + struct iovec *iov, struct iov_iter *i); + #endif