264 lines
6.7 KiB
C
264 lines
6.7 KiB
C
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
|
|
|
|
/*
|
|
* AF_XDP user-space access library.
|
|
*
|
|
* Copyright(c) 2018 - 2019 Intel Corporation.
|
|
*
|
|
* Author(s): Magnus Karlsson <magnus.karlsson@intel.com>
|
|
*/
|
|
|
|
#ifndef __LIBBPF_XSK_H
|
|
#define __LIBBPF_XSK_H
|
|
|
|
#include <stdio.h>
|
|
#include <stdint.h>
|
|
#include <linux/if_xdp.h>
|
|
|
|
#include "libbpf.h"
|
|
#include "libbpf_util.h"
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/* Do not access these members directly. Use the functions below. */
|
|
#define DEFINE_XSK_RING(name) \
|
|
struct name { \
|
|
__u32 cached_prod; \
|
|
__u32 cached_cons; \
|
|
__u32 mask; \
|
|
__u32 size; \
|
|
__u32 *producer; \
|
|
__u32 *consumer; \
|
|
void *ring; \
|
|
__u32 *flags; \
|
|
}
|
|
|
|
DEFINE_XSK_RING(xsk_ring_prod);
|
|
DEFINE_XSK_RING(xsk_ring_cons);
|
|
|
|
/* For a detailed explanation on the memory barriers associated with the
|
|
* ring, please take a look at net/xdp/xsk_queue.h.
|
|
*/
|
|
|
|
struct xsk_umem;
|
|
struct xsk_socket;
|
|
|
|
static inline __u64 *xsk_ring_prod__fill_addr(struct xsk_ring_prod *fill,
|
|
__u32 idx)
|
|
{
|
|
__u64 *addrs = (__u64 *)fill->ring;
|
|
|
|
return &addrs[idx & fill->mask];
|
|
}
|
|
|
|
static inline const __u64 *
|
|
xsk_ring_cons__comp_addr(const struct xsk_ring_cons *comp, __u32 idx)
|
|
{
|
|
const __u64 *addrs = (const __u64 *)comp->ring;
|
|
|
|
return &addrs[idx & comp->mask];
|
|
}
|
|
|
|
static inline struct xdp_desc *xsk_ring_prod__tx_desc(struct xsk_ring_prod *tx,
|
|
__u32 idx)
|
|
{
|
|
struct xdp_desc *descs = (struct xdp_desc *)tx->ring;
|
|
|
|
return &descs[idx & tx->mask];
|
|
}
|
|
|
|
static inline const struct xdp_desc *
|
|
xsk_ring_cons__rx_desc(const struct xsk_ring_cons *rx, __u32 idx)
|
|
{
|
|
const struct xdp_desc *descs = (const struct xdp_desc *)rx->ring;
|
|
|
|
return &descs[idx & rx->mask];
|
|
}
|
|
|
|
static inline int xsk_ring_prod__needs_wakeup(const struct xsk_ring_prod *r)
|
|
{
|
|
return *r->flags & XDP_RING_NEED_WAKEUP;
|
|
}
|
|
|
|
static inline __u32 xsk_prod_nb_free(struct xsk_ring_prod *r, __u32 nb)
|
|
{
|
|
__u32 free_entries = r->cached_cons - r->cached_prod;
|
|
|
|
if (free_entries >= nb)
|
|
return free_entries;
|
|
|
|
/* Refresh the local tail pointer.
|
|
* cached_cons is r->size bigger than the real consumer pointer so
|
|
* that this addition can be avoided in the more frequently
|
|
* executed code that computs free_entries in the beginning of
|
|
* this function. Without this optimization it whould have been
|
|
* free_entries = r->cached_prod - r->cached_cons + r->size.
|
|
*/
|
|
r->cached_cons = *r->consumer + r->size;
|
|
|
|
return r->cached_cons - r->cached_prod;
|
|
}
|
|
|
|
static inline __u32 xsk_cons_nb_avail(struct xsk_ring_cons *r, __u32 nb)
|
|
{
|
|
__u32 entries = r->cached_prod - r->cached_cons;
|
|
|
|
if (entries == 0) {
|
|
r->cached_prod = *r->producer;
|
|
entries = r->cached_prod - r->cached_cons;
|
|
}
|
|
|
|
return (entries > nb) ? nb : entries;
|
|
}
|
|
|
|
static inline __u32 xsk_ring_prod__reserve(struct xsk_ring_prod *prod, __u32 nb, __u32 *idx)
|
|
{
|
|
if (xsk_prod_nb_free(prod, nb) < nb)
|
|
return 0;
|
|
|
|
*idx = prod->cached_prod;
|
|
prod->cached_prod += nb;
|
|
|
|
return nb;
|
|
}
|
|
|
|
static inline void xsk_ring_prod__submit(struct xsk_ring_prod *prod, __u32 nb)
|
|
{
|
|
/* Make sure everything has been written to the ring before indicating
|
|
* this to the kernel by writing the producer pointer.
|
|
*/
|
|
libbpf_smp_wmb();
|
|
|
|
*prod->producer += nb;
|
|
}
|
|
|
|
static inline __u32 xsk_ring_cons__peek(struct xsk_ring_cons *cons, __u32 nb, __u32 *idx)
|
|
{
|
|
__u32 entries = xsk_cons_nb_avail(cons, nb);
|
|
|
|
if (entries > 0) {
|
|
/* Make sure we do not speculatively read the data before
|
|
* we have received the packet buffers from the ring.
|
|
*/
|
|
libbpf_smp_rmb();
|
|
|
|
*idx = cons->cached_cons;
|
|
cons->cached_cons += entries;
|
|
}
|
|
|
|
return entries;
|
|
}
|
|
|
|
static inline void xsk_ring_cons__cancel(struct xsk_ring_cons *cons, __u32 nb)
|
|
{
|
|
cons->cached_cons -= nb;
|
|
}
|
|
|
|
static inline void xsk_ring_cons__release(struct xsk_ring_cons *cons, __u32 nb)
|
|
{
|
|
/* Make sure data has been read before indicating we are done
|
|
* with the entries by updating the consumer pointer.
|
|
*/
|
|
libbpf_smp_rwmb();
|
|
|
|
*cons->consumer += nb;
|
|
}
|
|
|
|
static inline void *xsk_umem__get_data(void *umem_area, __u64 addr)
|
|
{
|
|
return &((char *)umem_area)[addr];
|
|
}
|
|
|
|
static inline __u64 xsk_umem__extract_addr(__u64 addr)
|
|
{
|
|
return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
|
|
}
|
|
|
|
static inline __u64 xsk_umem__extract_offset(__u64 addr)
|
|
{
|
|
return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
|
|
}
|
|
|
|
static inline __u64 xsk_umem__add_offset_to_addr(__u64 addr)
|
|
{
|
|
return xsk_umem__extract_addr(addr) + xsk_umem__extract_offset(addr);
|
|
}
|
|
|
|
LIBBPF_API int xsk_umem__fd(const struct xsk_umem *umem);
|
|
LIBBPF_API int xsk_socket__fd(const struct xsk_socket *xsk);
|
|
|
|
#define XSK_RING_CONS__DEFAULT_NUM_DESCS 2048
|
|
#define XSK_RING_PROD__DEFAULT_NUM_DESCS 2048
|
|
#define XSK_UMEM__DEFAULT_FRAME_SHIFT 12 /* 4096 bytes */
|
|
#define XSK_UMEM__DEFAULT_FRAME_SIZE (1 << XSK_UMEM__DEFAULT_FRAME_SHIFT)
|
|
#define XSK_UMEM__DEFAULT_FRAME_HEADROOM 0
|
|
#define XSK_UMEM__DEFAULT_FLAGS 0
|
|
|
|
struct xsk_umem_config {
|
|
__u32 fill_size;
|
|
__u32 comp_size;
|
|
__u32 frame_size;
|
|
__u32 frame_headroom;
|
|
__u32 flags;
|
|
};
|
|
|
|
LIBBPF_API int xsk_setup_xdp_prog(int ifindex,
|
|
int *xsks_map_fd);
|
|
LIBBPF_API int xsk_socket__update_xskmap(struct xsk_socket *xsk,
|
|
int xsks_map_fd);
|
|
|
|
/* Flags for the libbpf_flags field. */
|
|
#define XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD (1 << 0)
|
|
|
|
struct xsk_socket_config {
|
|
__u32 rx_size;
|
|
__u32 tx_size;
|
|
__u32 libbpf_flags;
|
|
__u32 xdp_flags;
|
|
__u16 bind_flags;
|
|
};
|
|
|
|
/* Set config to NULL to get the default configuration. */
|
|
LIBBPF_API int xsk_umem__create(struct xsk_umem **umem,
|
|
void *umem_area, __u64 size,
|
|
struct xsk_ring_prod *fill,
|
|
struct xsk_ring_cons *comp,
|
|
const struct xsk_umem_config *config);
|
|
LIBBPF_API int xsk_umem__create_v0_0_2(struct xsk_umem **umem,
|
|
void *umem_area, __u64 size,
|
|
struct xsk_ring_prod *fill,
|
|
struct xsk_ring_cons *comp,
|
|
const struct xsk_umem_config *config);
|
|
LIBBPF_API int xsk_umem__create_v0_0_4(struct xsk_umem **umem,
|
|
void *umem_area, __u64 size,
|
|
struct xsk_ring_prod *fill,
|
|
struct xsk_ring_cons *comp,
|
|
const struct xsk_umem_config *config);
|
|
LIBBPF_API int xsk_socket__create(struct xsk_socket **xsk,
|
|
const char *ifname, __u32 queue_id,
|
|
struct xsk_umem *umem,
|
|
struct xsk_ring_cons *rx,
|
|
struct xsk_ring_prod *tx,
|
|
const struct xsk_socket_config *config);
|
|
LIBBPF_API int
|
|
xsk_socket__create_shared(struct xsk_socket **xsk_ptr,
|
|
const char *ifname,
|
|
__u32 queue_id, struct xsk_umem *umem,
|
|
struct xsk_ring_cons *rx,
|
|
struct xsk_ring_prod *tx,
|
|
struct xsk_ring_prod *fill,
|
|
struct xsk_ring_cons *comp,
|
|
const struct xsk_socket_config *config);
|
|
|
|
/* Returns 0 for success and -EBUSY if the umem is still in use. */
|
|
LIBBPF_API int xsk_umem__delete(struct xsk_umem *umem);
|
|
LIBBPF_API void xsk_socket__delete(struct xsk_socket *xsk);
|
|
|
|
#ifdef __cplusplus
|
|
} /* extern "C" */
|
|
#endif
|
|
|
|
#endif /* __LIBBPF_XSK_H */
|