On Wed, 2022-06-22 at 05:15 +0100, Al Viro wrote:
> zero maxpages is bogus, but best treated as "just return 0";
> NULL pages, OTOH, should be treated as a hard bug.
>
> get rid of now completely useless checks in xarray_get_pages{,_alloc}().
>
> Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> ---
> lib/iov_iter.c | 9 ++-------
> 1 file changed, 2 insertions(+), 7 deletions(-)
>
> diff --git a/lib/iov_iter.c b/lib/iov_iter.c
> index 9c25661684c6..5c985cf2858e 100644
> --- a/lib/iov_iter.c
> +++ b/lib/iov_iter.c
> @@ -1271,9 +1271,6 @@ static ssize_t iter_xarray_get_pages(struct iov_iter *i,
> size_t size = maxsize;
> loff_t pos;
>
> - if (!size || !maxpages)
> - return 0;
> -
> pos = i->xarray_start + i->iov_offset;
> index = pos >> PAGE_SHIFT;
> offset = pos & ~PAGE_MASK;
> @@ -1365,10 +1362,11 @@ ssize_t iov_iter_get_pages(struct iov_iter *i,
>
> if (maxsize > i->count)
> maxsize = i->count;
> - if (!maxsize)
> + if (!maxsize || !maxpages)
> return 0;
> if (maxsize > MAX_RW_COUNT)
> maxsize = MAX_RW_COUNT;
> + BUG_ON(!pages);
>
> if (likely(user_backed_iter(i))) {
> unsigned int gup_flags = 0;
> @@ -1441,9 +1439,6 @@ static ssize_t iter_xarray_get_pages_alloc(struct iov_iter *i,
> size_t size = maxsize;
> loff_t pos;
>
> - if (!size)
> - return 0;
> -
> pos = i->xarray_start + i->iov_offset;
> index = pos >> PAGE_SHIFT;
> offset = pos & ~PAGE_MASK;
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
