[linux-2.6-block.git] / net / xdp / xsk_queue.c

// SPDX-License-Identifier: GPL-2.0
/* XDP user-space ring structure
 * Copyright(c) 2018 Intel Corporation.
 */

#include <linux/log2.h>
#include <linux/slab.h>
#include <linux/overflow.h>
#include <linux/vmalloc.h>
#include <net/xdp_sock_drv.h>

#include "xsk_queue.h"

static size_t xskq_get_ring_size(struct xsk_queue *q, bool umem_queue)
{
	struct xdp_umem_ring *umem_ring;
	struct xdp_rxtx_ring *rxtx_ring;

	if (umem_queue)
		return struct_size(umem_ring, desc, q->nentries);
	return struct_size(rxtx_ring, desc, q->nentries);
}

struct xsk_queue *xskq_create(u32 nentries, bool umem_queue)
{
	struct xsk_queue *q;
	size_t size;

	q = kzalloc(sizeof(*q), GFP_KERNEL);
	if (!q)
		return NULL;

	q->nentries = nentries;
	q->ring_mask = nentries - 1;

	size = xskq_get_ring_size(q, umem_queue);

	/* size which is overflowing or close to SIZE_MAX will become 0 in
	 * PAGE_ALIGN(), checking SIZE_MAX is enough due to the previous
	 * is_power_of_2(), the rest will be handled by vmalloc_user()
	 */
	if (unlikely(size == SIZE_MAX)) {
		kfree(q);
		return NULL;
	}

	size = PAGE_ALIGN(size);

	q->ring = vmalloc_user(size);
	if (!q->ring) {
		kfree(q);
		return NULL;
	}

	q->ring_vmalloc_size = size;
	return q;
}

void xskq_destroy(struct xsk_queue *q)
{
	if (!q)
		return;

	vfree(q->ring);
	kfree(q);
}
Commit	Line	Data
	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(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(q);
	44	return NULL;
	45	}
	46
	47	size = PAGE_ALIGN(size);
	48
	49	q->ring = vmalloc_user(size);
	50	if (!q->ring) {
	51	kfree(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(q->ring);
	65	kfree(q);
	66	}