Commit 4b179e9a authored by Al Viro's avatar Al Viro
Browse files

iterate_xarray(): only of the first iteration we might get offset != 0 



recalculating offset on each iteration is pointless - on all subsequent
passes through the loop it will be zero anyway.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent a6e4ec7b

lib/iov_iter.c

+3 −3
Original line number Diff line number Diff line
@@ -70,9 +70,9 @@ 
	__label__ __out;					\

	size_t __off = 0;					\

	struct page *head = NULL;				\

	size_t offset;						\

	loff_t start = i->xarray_start + i->iov_offset;		\

	pgoff_t index = start >> PAGE_SHIFT;			\

	unsigned offset = start % PAGE_SIZE;			\

	pgoff_t index = start / PAGE_SIZE;			\

	int j;							\

								\

	XA_STATE(xas, i->xarray, index);			\
@@ -89,7 +89,6 @@ 
		for (j = (head->index < index) ? index - head->index : 0; \

		     j < thp_nr_pages(head); j++) {		\

			void *kaddr = kmap_local_page(head + j);	\

			offset = (start + __off) % PAGE_SIZE;	\

			base = kaddr + offset;			\

			len = PAGE_SIZE - offset;		\

			len = min(n, len);			\
@@ -100,6 +99,7 @@ 
			n -= len;				\

			if (left || n == 0)			\

				goto __out;			\

			offset = 0;				\

		}						\

	}							\

__out:								\