diff options
Diffstat (limited to 'include/linux/uio.h')
| -rw-r--r-- | include/linux/uio.h | 96 |
1 files changed, 65 insertions, 31 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h index 6350354f97e9..2e3134b14ffd 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -7,6 +7,7 @@ #include <linux/kernel.h> #include <linux/thread_info.h> +#include <linux/mm_types.h> #include <uapi/linux/uio.h> struct page; @@ -25,6 +26,7 @@ enum iter_type { ITER_PIPE, ITER_XARRAY, ITER_DISCARD, + ITER_UBUF, }; struct iov_iter_state { @@ -37,7 +39,11 @@ struct iov_iter { u8 iter_type; bool nofault; bool data_source; - size_t iov_offset; + bool user_backed; + union { + size_t iov_offset; + int last_offset; + }; size_t count; union { const struct iovec *iov; @@ -45,6 +51,7 @@ struct iov_iter { const struct bio_vec *bvec; struct xarray *xarray; struct pipe_inode_info *pipe; + void __user *ubuf; }; union { unsigned long nr_segs; @@ -69,6 +76,11 @@ static inline void iov_iter_save_state(struct iov_iter *iter, state->nr_segs = iter->nr_segs; } +static inline bool iter_is_ubuf(const struct iov_iter *i) +{ + return iov_iter_type(i) == ITER_UBUF; +} + static inline bool iter_is_iovec(const struct iov_iter *i) { return iov_iter_type(i) == ITER_IOVEC; @@ -104,6 +116,11 @@ static inline unsigned char iov_iter_rw(const struct iov_iter *i) return i->data_source ? WRITE : READ; } +static inline bool user_backed_iter(const struct iov_iter *i) +{ + return i->user_backed; +} + /* * Total number of bytes covered by an iovec. * @@ -146,22 +163,26 @@ size_t _copy_to_iter(const 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); +static inline size_t copy_folio_to_iter(struct folio *folio, size_t offset, + size_t bytes, struct iov_iter *i) +{ + return copy_page_to_iter(&folio->page, offset, bytes, i); +} + static __always_inline __must_check size_t copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i) { - if (unlikely(!check_copy_size(addr, bytes, true))) - return 0; - else + if (check_copy_size(addr, bytes, true)) return _copy_to_iter(addr, bytes, i); + return 0; } static __always_inline __must_check size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i) { - if (unlikely(!check_copy_size(addr, bytes, false))) - return 0; - else + if (check_copy_size(addr, bytes, false)) return _copy_from_iter(addr, bytes, i); + return 0; } static __always_inline __must_check @@ -177,10 +198,9 @@ bool copy_from_iter_full(void *addr, size_t bytes, struct iov_iter *i) static __always_inline __must_check size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i) { - if (unlikely(!check_copy_size(addr, bytes, false))) - return 0; - else + if (check_copy_size(addr, bytes, false)) return _copy_from_iter_nocache(addr, bytes, i); + return 0; } static __always_inline __must_check @@ -196,7 +216,7 @@ bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i) #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE /* * Note, users like pmem that depend on the stricter semantics of - * copy_from_iter_flushcache() than copy_from_iter_nocache() must check for + * _copy_from_iter_flushcache() than _copy_from_iter_nocache() must check for * IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) before assuming that the * destination is flushed from the cache on return. */ @@ -211,25 +231,9 @@ size_t _copy_mc_to_iter(const void *addr, size_t bytes, struct iov_iter *i); #define _copy_mc_to_iter _copy_to_iter #endif -static __always_inline __must_check -size_t copy_from_iter_flushcache(void *addr, size_t bytes, struct iov_iter *i) -{ - if (unlikely(!check_copy_size(addr, bytes, false))) - return 0; - else - return _copy_from_iter_flushcache(addr, bytes, i); -} - -static __always_inline __must_check -size_t copy_mc_to_iter(void *addr, size_t bytes, struct iov_iter *i) -{ - if (unlikely(!check_copy_size(addr, bytes, true))) - return 0; - else - return _copy_mc_to_iter(addr, bytes, i); -} - size_t iov_iter_zero(size_t bytes, struct iov_iter *); +bool iov_iter_is_aligned(const struct iov_iter *i, unsigned addr_mask, + unsigned len_mask); unsigned long iov_iter_alignment(const struct iov_iter *i); unsigned long iov_iter_gap_alignment(const struct iov_iter *i); void iov_iter_init(struct iov_iter *i, unsigned int direction, const struct iovec *iov, @@ -243,9 +247,9 @@ void iov_iter_pipe(struct iov_iter *i, unsigned int direction, struct pipe_inode void iov_iter_discard(struct iov_iter *i, unsigned int direction, size_t count); void iov_iter_xarray(struct iov_iter *i, unsigned int direction, struct xarray *xarray, loff_t start, size_t count); -ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages, +ssize_t iov_iter_get_pages2(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, +ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i, struct page ***pages, size_t maxsize, size_t *start); int iov_iter_npages(const struct iov_iter *i, int maxpages); void iov_iter_restore(struct iov_iter *i, struct iov_iter_state *state); @@ -284,6 +288,23 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count) i->count = count; } +static inline int +iov_iter_npages_cap(struct iov_iter *i, int maxpages, size_t max_bytes) +{ + size_t shorted = 0; + int npages; + + if (iov_iter_count(i) > max_bytes) { + shorted = iov_iter_count(i) - max_bytes; + iov_iter_truncate(i, max_bytes); + } + npages = iov_iter_npages(i, maxpages); + if (shorted) + iov_iter_reexpand(i, iov_iter_count(i) + shorted); + + return npages; +} + struct csum_state { __wsum csum; size_t off; @@ -317,4 +338,17 @@ ssize_t __import_iovec(int type, const struct iovec __user *uvec, int import_single_range(int type, void __user *buf, size_t len, struct iovec *iov, struct iov_iter *i); +static inline void iov_iter_ubuf(struct iov_iter *i, unsigned int direction, + void __user *buf, size_t count) +{ + WARN_ON(direction & ~(READ | WRITE)); + *i = (struct iov_iter) { + .iter_type = ITER_UBUF, + .user_backed = true, + .data_source = direction, + .ubuf = buf, + .count = count + }; +} + #endif |