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 <linux/vmalloc.h> |
10 | #include <net/xdp_sock_drv.h> |
11 | |
12 | #include "xsk_queue.h" |
13 | |
14 | static size_t xskq_get_ring_size(struct xsk_queue *q, bool umem_queue) |
15 | { |
16 | struct xdp_umem_ring *umem_ring; |
17 | struct xdp_rxtx_ring *rxtx_ring; |
18 | |
19 | if (umem_queue) |
20 | return struct_size(umem_ring, desc, q->nentries); |
21 | return struct_size(rxtx_ring, desc, q->nentries); |
22 | } |
23 | |
24 | struct xsk_queue *xskq_create(u32 nentries, bool umem_queue) |
25 | { |
26 | struct xsk_queue *q; |
27 | size_t size; |
28 | |
29 | q = kzalloc(size: sizeof(*q), GFP_KERNEL); |
30 | if (!q) |
31 | return NULL; |
32 | |
33 | q->nentries = nentries; |
34 | q->ring_mask = nentries - 1; |
35 | |
36 | size = xskq_get_ring_size(q, umem_queue); |
37 | |
38 | /* size which is overflowing or close to SIZE_MAX will become 0 in |
39 | * PAGE_ALIGN(), checking SIZE_MAX is enough due to the previous |
40 | * is_power_of_2(), the rest will be handled by vmalloc_user() |
41 | */ |
42 | if (unlikely(size == SIZE_MAX)) { |
43 | kfree(objp: q); |
44 | return NULL; |
45 | } |
46 | |
47 | size = PAGE_ALIGN(size); |
48 | |
49 | q->ring = vmalloc_user(size); |
50 | if (!q->ring) { |
51 | kfree(objp: q); |
52 | return NULL; |
53 | } |
54 | |
55 | q->ring_vmalloc_size = size; |
56 | return q; |
57 | } |
58 | |
59 | void xskq_destroy(struct xsk_queue *q) |
60 | { |
61 | if (!q) |
62 | return; |
63 | |
64 | vfree(addr: q->ring); |
65 | kfree(objp: q); |
66 | } |
67 | |