Commit 91329559 authored by Al Viro's avatar Al Viro
Browse files

iov_iter_get_pages_alloc(): lift freeing pages array on failure exits into wrapper 



Incidentally, ITER_XARRAY did *not* free the sucker in case when
iter_xarray_populate_pages() returned 0...

Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 12d426ab

lib/iov_iter.c

+22 −16
Original line number Diff line number Diff line
@@ -1506,15 +1506,10 @@ static ssize_t pipe_get_pages_alloc(struct iov_iter *i, 
		maxsize = n;

	else

		npages = DIV_ROUND_UP(maxsize + off, PAGE_SIZE);

	p = get_pages_array(npages);

	*pages = p = get_pages_array(npages);

	if (!p)

		return -ENOMEM;

	n = __pipe_get_pages(i, maxsize, p, off);

	if (n > 0)

		*pages = p;

	else

		kvfree(p);

	return n;

	return __pipe_get_pages(i, maxsize, p, off);

}



static ssize_t iter_xarray_get_pages_alloc(struct iov_iter *i,
@@ -1544,10 +1539,9 @@ static ssize_t iter_xarray_get_pages_alloc(struct iov_iter *i, 
			count++;

	}



	p = get_pages_array(count);

	*pages = p = get_pages_array(count);

	if (!p)

		return -ENOMEM;

	*pages = p;



	nr = iter_xarray_populate_pages(p, i->xarray, index, count);

	if (nr == 0)
@@ -1556,7 +1550,7 @@ static ssize_t iter_xarray_get_pages_alloc(struct iov_iter *i, 
	return min_t(size_t, nr * PAGE_SIZE - offset, maxsize);

}



ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,

static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,

		   struct page ***pages, size_t maxsize,

		   size_t *start)

{
@@ -1583,16 +1577,12 @@ ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, 
		*start = addr % PAGE_SIZE;

		addr &= PAGE_MASK;

		n = DIV_ROUND_UP(maxsize + *start, PAGE_SIZE);

		p = get_pages_array(n);

		*pages = p = get_pages_array(n);

		if (!p)

			return -ENOMEM;

		res = get_user_pages_fast(addr, n, gup_flags, p);

		if (unlikely(res <= 0)) {

			kvfree(p);

			*pages = NULL;

		if (unlikely(res <= 0))

			return res;

		}

		*pages = p;

		return min_t(size_t, maxsize, res * PAGE_SIZE - *start);

	}

	if (iov_iter_is_bvec(i)) {
@@ -1613,6 +1603,22 @@ ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, 
		return iter_xarray_get_pages_alloc(i, pages, maxsize, start);

	return -EFAULT;

}



ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,

		   struct page ***pages, size_t maxsize,

		   size_t *start)

{

	ssize_t len;



	*pages = NULL;



	len = __iov_iter_get_pages_alloc(i, pages, maxsize, start);

	if (len <= 0) {

		kvfree(*pages);

		*pages = NULL;

	}

	return len;

}

EXPORT_SYMBOL(iov_iter_get_pages_alloc);



size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,