new helper: iov_iter_get_pages()
iov_iter_get_pages(iter, pages, maxsize, &start) grabs references pinning
the pages of up to maxsize of (contiguous) data from iter. Returns the
amount of memory grabbed or -error. In case of success, the requested
area begins at offset start in pages[0] and runs through pages[1], etc.
Less than requested amount might be returned - either because the contiguous
area in the beginning of iterator is smaller than requested, or because
the kernel failed to pin that many pages.
direct-io.c switched to using iov_iter_get_pages()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/uio.h b/include/linux/uio.h
index b80bbe1..3419861 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -71,6 +71,8 @@
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);
static inline size_t iov_iter_count(struct iov_iter *i)
{