On Wed, 2022-06-22 at 05:15 +0100, Al Viro wrote:
> same as for pipes
>
> Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> ---
> lib/iov_iter.c | 49 ++++++++++---------------------------------------
> 1 file changed, 10 insertions(+), 39 deletions(-)
>
> diff --git a/lib/iov_iter.c b/lib/iov_iter.c
> index 1c98f2f3a581..07dacb274ba5 100644
> --- a/lib/iov_iter.c
> +++ b/lib/iov_iter.c
> @@ -1276,7 +1276,7 @@ static ssize_t iter_xarray_populate_pages(struct page **pages, struct xarray *xa
> }
>
> static ssize_t iter_xarray_get_pages(struct iov_iter *i,
> - struct page **pages, size_t maxsize,
> + struct page ***pages, size_t maxsize,
> unsigned maxpages, size_t *_start_offset)
> {
> unsigned nr, offset;
> @@ -1301,7 +1301,13 @@ static ssize_t iter_xarray_get_pages(struct iov_iter *i,
> if (count > maxpages)
> count = maxpages;
>
> - nr = iter_xarray_populate_pages(pages, i->xarray, index, count);
> + if (!*pages) {
> + *pages = get_pages_array(count);
> + if (!*pages)
> + return -ENOMEM;
> + }
> +
> + nr = iter_xarray_populate_pages(*pages, i->xarray, index, count);
> if (nr == 0)
> return 0;
>
> @@ -1409,46 +1415,11 @@ ssize_t iov_iter_get_pages(struct iov_iter *i,
> if (iov_iter_is_pipe(i))
> return pipe_get_pages(i, &pages, maxsize, maxpages, start);
> if (iov_iter_is_xarray(i))
> - return iter_xarray_get_pages(i, pages, maxsize, maxpages, start);
> + return iter_xarray_get_pages(i, &pages, maxsize, maxpages, start);
> return -EFAULT;
> }
> EXPORT_SYMBOL(iov_iter_get_pages);
>
> -static ssize_t iter_xarray_get_pages_alloc(struct iov_iter *i,
> - struct page ***pages, size_t maxsize,
> - size_t *_start_offset)
> -{
> - struct page **p;
> - unsigned nr, offset;
> - pgoff_t index, count;
> - size_t size = maxsize;
> - loff_t pos;
> -
> - pos = i->xarray_start + i->iov_offset;
> - index = pos >> PAGE_SHIFT;
> - offset = pos & ~PAGE_MASK;
> - *_start_offset = offset;
> -
> - count = 1;
> - if (size > PAGE_SIZE - offset) {
> - size -= PAGE_SIZE - offset;
> - count += size >> PAGE_SHIFT;
> - size &= ~PAGE_MASK;
> - if (size)
> - count++;
> - }
> -
> - *pages = p = get_pages_array(count);
> - if (!p)
> - return -ENOMEM;
> -
> - nr = iter_xarray_populate_pages(p, i->xarray, index, count);
> - if (nr == 0)
> - return 0;
> -
> - return min_t(size_t, nr * PAGE_SIZE - offset, maxsize);
> -}
> -
> static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
> struct page ***pages, size_t maxsize,
> size_t *start)
> @@ -1498,7 +1469,7 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
> if (iov_iter_is_pipe(i))
> return pipe_get_pages(i, pages, maxsize, ~0U, start);
> if (iov_iter_is_xarray(i))
> - return iter_xarray_get_pages_alloc(i, pages, maxsize, start);
> + return iter_xarray_get_pages(i, pages, maxsize, ~0U, start);
> return -EFAULT;
> }
>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
