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
xskq_get_ring_size(struct xsk_queue * q,bool umem_queue)13 static 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
xskq_create(u32 nentries,bool umem_queue)23 struct 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
xskq_destroy(struct xsk_queue * q)50 void xskq_destroy(struct xsk_queue *q)
51 {
52 if (!q)
53 return;
54
55 page_frag_free(q->ring);
56 kfree(q);
57 }
58