1// SPDX-License-Identifier: GPL-2.0
 2/* XDP user-space ring structure
 3 * Copyright(c) 2018 Intel Corporation.
 4 */
 5
 6#include <linux/log2.h>
 7#include <linux/slab.h>
 8#include <linux/overflow.h>
 9#include <net/xdp_sock_drv.h>
10
11#include "xsk_queue.h"
12
13static size_t xskq_get_ring_size(struct xsk_queue *q, bool umem_queue)
14{
15	struct xdp_umem_ring *umem_ring;
16	struct xdp_rxtx_ring *rxtx_ring;
17
18	if (umem_queue)
19		return struct_size(umem_ring, desc, q->nentries);
20	return struct_size(rxtx_ring, desc, q->nentries);
21}
22
23struct xsk_queue *xskq_create(u32 nentries, bool umem_queue)
24{
25	struct xsk_queue *q;
26	gfp_t gfp_flags;
27	size_t size;
28
29	q = kzalloc(sizeof(*q), GFP_KERNEL);
30	if (!q)
31		return NULL;
32
33	q->nentries = nentries;
34	q->ring_mask = nentries - 1;
35
36	gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN |
37		    __GFP_COMP  | __GFP_NORETRY;
38	size = xskq_get_ring_size(q, umem_queue);
39
40	q->ring = (struct xdp_ring *)__get_free_pages(gfp_flags,
41						      get_order(size));
42	if (!q->ring) {
43		kfree(q);
44		return NULL;
45	}
46
47	return q;
48}
49
50void xskq_destroy(struct xsk_queue *q)
51{
52	if (!q)
53		return;
54
55	page_frag_free(q->ring);
56	kfree(q);
57}