iov_iter: advancing variants of iov_iter_get_pages{,_alloc}()

[linux-2.6-microblaze.git] / include / linux / uio.h

diff --git a/include/linux/uio.h b/include/linux/uio.h
index 739285f..b70d286 100644 (file)
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -26,6 +26,7 @@ enum iter_type {
        ITER_PIPE,
        ITER_XARRAY,
        ITER_DISCARD,
+       ITER_UBUF,
 };
 
 struct iov_iter_state {
@@ -38,7 +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;
@@ -46,6 +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;
@@ -70,6 +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;
@@ -105,6 +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.
  *
@@ -156,19 +172,17 @@ static inline size_t copy_folio_to_iter(struct folio *folio, size_t offset,
 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
@@ -184,10 +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
@@ -219,6 +232,8 @@ size_t _copy_mc_to_iter(const void *addr, size_t bytes, struct iov_iter *i);
 #endif
 
 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,
@@ -323,4 +338,37 @@ 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
+       };
+}
+
+static inline ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
+                       size_t maxsize, unsigned maxpages, size_t *start)
+{
+       ssize_t res = iov_iter_get_pages(i, pages, maxsize, maxpages, start);
+
+       if (res >= 0)
+               iov_iter_advance(i, res);
+       return res;
+}
+
+static inline ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i, struct page ***pages,
+                       size_t maxsize, size_t *start)
+{
+       ssize_t res = iov_iter_get_pages_alloc(i, pages, maxsize, start);
+
+       if (res >= 0)
+               iov_iter_advance(i, res);
+       return res;
+}
+
 #endif