+struct iov_iter_ops {
+ size_t (*ii_copy_to_user_atomic)(struct page *, struct iov_iter *,
+ unsigned long, size_t);
+ size_t (*ii_copy_to_user)(struct page *, struct iov_iter *,
+ unsigned long, size_t, int);
+ size_t (*ii_copy_from_user_atomic)(struct page *, struct iov_iter *,
+ unsigned long, size_t);
+ size_t (*ii_copy_from_user)(struct page *, struct iov_iter *,
+ unsigned long, size_t);
+ void (*ii_advance)(struct iov_iter *, size_t);
+ int (*ii_fault_in_readable)(struct iov_iter *, size_t);
+ size_t (*ii_single_seg_count)(const struct iov_iter *);
+ int (*ii_shorten)(struct iov_iter *, size_t);
+};
+
+static inline size_t iov_iter_copy_to_user_atomic(struct page *page,
+ struct iov_iter *i, unsigned long offset, size_t bytes)
+{
+ return i->ops->ii_copy_to_user_atomic(page, i, offset, bytes);
+}
+static inline size_t __iov_iter_copy_to_user(struct page *page,
+ struct iov_iter *i, unsigned long offset, size_t bytes)
+{
+ return i->ops->ii_copy_to_user(page, i, offset, bytes, 0);
+}
+static inline size_t iov_iter_copy_to_user(struct page *page,
+ struct iov_iter *i, unsigned long offset, size_t bytes)
+{
+ return i->ops->ii_copy_to_user(page, i, offset, bytes, 1);
+}
+static inline size_t iov_iter_copy_from_user_atomic(struct page *page,
+ struct iov_iter *i, unsigned long offset, size_t bytes)
+{
+ return i->ops->ii_copy_from_user_atomic(page, i, offset, bytes);
+}
+static inline size_t iov_iter_copy_from_user(struct page *page,
+ struct iov_iter *i, unsigned long offset, size_t bytes)
+{
+ return i->ops->ii_copy_from_user(page, i, offset, bytes);
+}
+static inline void iov_iter_advance(struct iov_iter *i, size_t bytes)
+{
+ return i->ops->ii_advance(i, bytes);
+}
+static inline int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes)
+{
+ return i->ops->ii_fault_in_readable(i, bytes);
+}
+static inline size_t iov_iter_single_seg_count(const struct iov_iter *i)
+{
+ return i->ops->ii_single_seg_count(i);
+}
+static inline int iov_iter_shorten(struct iov_iter *i, size_t count)
+{
+ return i->ops->ii_shorten(i, count);
+}
+
+#ifdef CONFIG_BLOCK
+extern struct iov_iter_ops ii_bvec_ops;
+
+struct bio_vec;
+static inline void iov_iter_init_bvec(struct iov_iter *i,
+ struct bio_vec *bvec,
+ unsigned long nr_segs,
+ size_t count, size_t written)
+{
+ i->ops = &ii_bvec_ops;
+ i->data = (unsigned long)bvec;
+ i->nr_segs = nr_segs;
+ i->iov_offset = 0;
+ i->count = count + written;
+
+ iov_iter_advance(i, written);
+}
+
+static inline int iov_iter_has_bvec(struct iov_iter *i)
+{
+ return i->ops == &ii_bvec_ops;
+}
+
+static inline struct bio_vec *iov_iter_bvec(struct iov_iter *i)
+{
+ BUG_ON(!iov_iter_has_bvec(i));
+ return (struct bio_vec *)i->data;
+}
+#endif
+
+extern struct iov_iter_ops ii_iovec_ops;