diff options
Diffstat (limited to 'tools/testing/selftests/bpf/xsk.c')
-rw-r--r-- | tools/testing/selftests/bpf/xsk.c | 779 |
1 files changed, 779 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/xsk.c b/tools/testing/selftests/bpf/xsk.c new file mode 100644 index 0000000000..d9fb2b730a --- /dev/null +++ b/tools/testing/selftests/bpf/xsk.c @@ -0,0 +1,779 @@ +// 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> + */ + +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <arpa/inet.h> +#include <asm/barrier.h> +#include <linux/compiler.h> +#include <linux/ethtool.h> +#include <linux/filter.h> +#include <linux/if_ether.h> +#include <linux/if_link.h> +#include <linux/if_packet.h> +#include <linux/if_xdp.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/netlink.h> +#include <linux/rtnetlink.h> +#include <linux/sockios.h> +#include <net/if.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/socket.h> +#include <sys/types.h> + +#include <bpf/bpf.h> +#include <bpf/libbpf.h> +#include "xsk.h" +#include "bpf_util.h" + +#ifndef SOL_XDP + #define SOL_XDP 283 +#endif + +#ifndef AF_XDP + #define AF_XDP 44 +#endif + +#ifndef PF_XDP + #define PF_XDP AF_XDP +#endif + +#define pr_warn(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__) + +#define XSKMAP_SIZE 1 + +struct xsk_umem { + struct xsk_ring_prod *fill_save; + struct xsk_ring_cons *comp_save; + char *umem_area; + struct xsk_umem_config config; + int fd; + int refcount; + struct list_head ctx_list; + bool rx_ring_setup_done; + bool tx_ring_setup_done; +}; + +struct xsk_ctx { + struct xsk_ring_prod *fill; + struct xsk_ring_cons *comp; + __u32 queue_id; + struct xsk_umem *umem; + int refcount; + int ifindex; + struct list_head list; +}; + +struct xsk_socket { + struct xsk_ring_cons *rx; + struct xsk_ring_prod *tx; + struct xsk_ctx *ctx; + struct xsk_socket_config config; + int fd; +}; + +struct nl_mtu_req { + struct nlmsghdr nh; + struct ifinfomsg msg; + char buf[512]; +}; + +int xsk_umem__fd(const struct xsk_umem *umem) +{ + return umem ? umem->fd : -EINVAL; +} + +int xsk_socket__fd(const struct xsk_socket *xsk) +{ + return xsk ? xsk->fd : -EINVAL; +} + +static bool xsk_page_aligned(void *buffer) +{ + unsigned long addr = (unsigned long)buffer; + + return !(addr & (getpagesize() - 1)); +} + +static void xsk_set_umem_config(struct xsk_umem_config *cfg, + const struct xsk_umem_config *usr_cfg) +{ + if (!usr_cfg) { + cfg->fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS; + cfg->comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS; + cfg->frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE; + cfg->frame_headroom = XSK_UMEM__DEFAULT_FRAME_HEADROOM; + cfg->flags = XSK_UMEM__DEFAULT_FLAGS; + return; + } + + cfg->fill_size = usr_cfg->fill_size; + cfg->comp_size = usr_cfg->comp_size; + cfg->frame_size = usr_cfg->frame_size; + cfg->frame_headroom = usr_cfg->frame_headroom; + cfg->flags = usr_cfg->flags; +} + +static int xsk_set_xdp_socket_config(struct xsk_socket_config *cfg, + const struct xsk_socket_config *usr_cfg) +{ + if (!usr_cfg) { + cfg->rx_size = XSK_RING_CONS__DEFAULT_NUM_DESCS; + cfg->tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS; + cfg->bind_flags = 0; + return 0; + } + + cfg->rx_size = usr_cfg->rx_size; + cfg->tx_size = usr_cfg->tx_size; + cfg->bind_flags = usr_cfg->bind_flags; + + return 0; +} + +static int xsk_get_mmap_offsets(int fd, struct xdp_mmap_offsets *off) +{ + socklen_t optlen; + int err; + + optlen = sizeof(*off); + err = getsockopt(fd, SOL_XDP, XDP_MMAP_OFFSETS, off, &optlen); + if (err) + return err; + + if (optlen == sizeof(*off)) + return 0; + + return -EINVAL; +} + +static int xsk_create_umem_rings(struct xsk_umem *umem, int fd, + struct xsk_ring_prod *fill, + struct xsk_ring_cons *comp) +{ + struct xdp_mmap_offsets off; + void *map; + int err; + + err = setsockopt(fd, SOL_XDP, XDP_UMEM_FILL_RING, + &umem->config.fill_size, + sizeof(umem->config.fill_size)); + if (err) + return -errno; + + err = setsockopt(fd, SOL_XDP, XDP_UMEM_COMPLETION_RING, + &umem->config.comp_size, + sizeof(umem->config.comp_size)); + if (err) + return -errno; + + err = xsk_get_mmap_offsets(fd, &off); + if (err) + return -errno; + + map = mmap(NULL, off.fr.desc + umem->config.fill_size * sizeof(__u64), + PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd, + XDP_UMEM_PGOFF_FILL_RING); + if (map == MAP_FAILED) + return -errno; + + fill->mask = umem->config.fill_size - 1; + fill->size = umem->config.fill_size; + fill->producer = map + off.fr.producer; + fill->consumer = map + off.fr.consumer; + fill->flags = map + off.fr.flags; + fill->ring = map + off.fr.desc; + fill->cached_cons = umem->config.fill_size; + + map = mmap(NULL, off.cr.desc + umem->config.comp_size * sizeof(__u64), + PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd, + XDP_UMEM_PGOFF_COMPLETION_RING); + if (map == MAP_FAILED) { + err = -errno; + goto out_mmap; + } + + comp->mask = umem->config.comp_size - 1; + comp->size = umem->config.comp_size; + comp->producer = map + off.cr.producer; + comp->consumer = map + off.cr.consumer; + comp->flags = map + off.cr.flags; + comp->ring = map + off.cr.desc; + + return 0; + +out_mmap: + munmap(map, off.fr.desc + umem->config.fill_size * sizeof(__u64)); + return err; +} + +int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area, + __u64 size, struct xsk_ring_prod *fill, + struct xsk_ring_cons *comp, + const struct xsk_umem_config *usr_config) +{ + struct xdp_umem_reg mr; + struct xsk_umem *umem; + int err; + + if (!umem_area || !umem_ptr || !fill || !comp) + return -EFAULT; + if (!size && !xsk_page_aligned(umem_area)) + return -EINVAL; + + umem = calloc(1, sizeof(*umem)); + if (!umem) + return -ENOMEM; + + umem->fd = socket(AF_XDP, SOCK_RAW | SOCK_CLOEXEC, 0); + if (umem->fd < 0) { + err = -errno; + goto out_umem_alloc; + } + + umem->umem_area = umem_area; + INIT_LIST_HEAD(&umem->ctx_list); + xsk_set_umem_config(&umem->config, usr_config); + + memset(&mr, 0, sizeof(mr)); + mr.addr = (uintptr_t)umem_area; + mr.len = size; + mr.chunk_size = umem->config.frame_size; + mr.headroom = umem->config.frame_headroom; + mr.flags = umem->config.flags; + + err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_REG, &mr, sizeof(mr)); + if (err) { + err = -errno; + goto out_socket; + } + + err = xsk_create_umem_rings(umem, umem->fd, fill, comp); + if (err) + goto out_socket; + + umem->fill_save = fill; + umem->comp_save = comp; + *umem_ptr = umem; + return 0; + +out_socket: + close(umem->fd); +out_umem_alloc: + free(umem); + return err; +} + +bool xsk_is_in_mode(u32 ifindex, int mode) +{ + LIBBPF_OPTS(bpf_xdp_query_opts, opts); + int ret; + + ret = bpf_xdp_query(ifindex, mode, &opts); + if (ret) { + printf("XDP mode query returned error %s\n", strerror(errno)); + return false; + } + + if (mode == XDP_FLAGS_DRV_MODE) + return opts.attach_mode == XDP_ATTACHED_DRV; + else if (mode == XDP_FLAGS_SKB_MODE) + return opts.attach_mode == XDP_ATTACHED_SKB; + + return false; +} + +/* Lifted from netlink.c in tools/lib/bpf */ +static int netlink_recvmsg(int sock, struct msghdr *mhdr, int flags) +{ + int len; + + do { + len = recvmsg(sock, mhdr, flags); + } while (len < 0 && (errno == EINTR || errno == EAGAIN)); + + if (len < 0) + return -errno; + return len; +} + +/* Lifted from netlink.c in tools/lib/bpf */ +static int alloc_iov(struct iovec *iov, int len) +{ + void *nbuf; + + nbuf = realloc(iov->iov_base, len); + if (!nbuf) + return -ENOMEM; + + iov->iov_base = nbuf; + iov->iov_len = len; + return 0; +} + +/* Original version lifted from netlink.c in tools/lib/bpf */ +static int netlink_recv(int sock) +{ + struct iovec iov = {}; + struct msghdr mhdr = { + .msg_iov = &iov, + .msg_iovlen = 1, + }; + bool multipart = true; + struct nlmsgerr *err; + struct nlmsghdr *nh; + int len, ret; + + ret = alloc_iov(&iov, 4096); + if (ret) + goto done; + + while (multipart) { + multipart = false; + len = netlink_recvmsg(sock, &mhdr, MSG_PEEK | MSG_TRUNC); + if (len < 0) { + ret = len; + goto done; + } + + if (len > iov.iov_len) { + ret = alloc_iov(&iov, len); + if (ret) + goto done; + } + + len = netlink_recvmsg(sock, &mhdr, 0); + if (len < 0) { + ret = len; + goto done; + } + + if (len == 0) + break; + + for (nh = (struct nlmsghdr *)iov.iov_base; NLMSG_OK(nh, len); + nh = NLMSG_NEXT(nh, len)) { + if (nh->nlmsg_flags & NLM_F_MULTI) + multipart = true; + switch (nh->nlmsg_type) { + case NLMSG_ERROR: + err = (struct nlmsgerr *)NLMSG_DATA(nh); + if (!err->error) + continue; + ret = err->error; + goto done; + case NLMSG_DONE: + ret = 0; + goto done; + default: + break; + } + } + } + ret = 0; +done: + free(iov.iov_base); + return ret; +} + +int xsk_set_mtu(int ifindex, int mtu) +{ + struct nl_mtu_req req; + struct rtattr *rta; + int fd, ret; + + fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE); + if (fd < 0) + return fd; + + memset(&req, 0, sizeof(req)); + req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)); + req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; + req.nh.nlmsg_type = RTM_NEWLINK; + req.msg.ifi_family = AF_UNSPEC; + req.msg.ifi_index = ifindex; + rta = (struct rtattr *)(((char *)&req) + NLMSG_ALIGN(req.nh.nlmsg_len)); + rta->rta_type = IFLA_MTU; + rta->rta_len = RTA_LENGTH(sizeof(unsigned int)); + req.nh.nlmsg_len = NLMSG_ALIGN(req.nh.nlmsg_len) + RTA_LENGTH(sizeof(mtu)); + memcpy(RTA_DATA(rta), &mtu, sizeof(mtu)); + + ret = send(fd, &req, req.nh.nlmsg_len, 0); + if (ret < 0) { + close(fd); + return errno; + } + + ret = netlink_recv(fd); + close(fd); + return ret; +} + +int xsk_attach_xdp_program(struct bpf_program *prog, int ifindex, u32 xdp_flags) +{ + int prog_fd; + + prog_fd = bpf_program__fd(prog); + return bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL); +} + +void xsk_detach_xdp_program(int ifindex, u32 xdp_flags) +{ + bpf_xdp_detach(ifindex, xdp_flags, NULL); +} + +void xsk_clear_xskmap(struct bpf_map *map) +{ + u32 index = 0; + int map_fd; + + map_fd = bpf_map__fd(map); + bpf_map_delete_elem(map_fd, &index); +} + +int xsk_update_xskmap(struct bpf_map *map, struct xsk_socket *xsk) +{ + int map_fd, sock_fd; + u32 index = 0; + + map_fd = bpf_map__fd(map); + sock_fd = xsk_socket__fd(xsk); + + return bpf_map_update_elem(map_fd, &index, &sock_fd, 0); +} + +static struct xsk_ctx *xsk_get_ctx(struct xsk_umem *umem, int ifindex, + __u32 queue_id) +{ + struct xsk_ctx *ctx; + + if (list_empty(&umem->ctx_list)) + return NULL; + + list_for_each_entry(ctx, &umem->ctx_list, list) { + if (ctx->ifindex == ifindex && ctx->queue_id == queue_id) { + ctx->refcount++; + return ctx; + } + } + + return NULL; +} + +static void xsk_put_ctx(struct xsk_ctx *ctx, bool unmap) +{ + struct xsk_umem *umem = ctx->umem; + struct xdp_mmap_offsets off; + int err; + + if (--ctx->refcount) + return; + + if (!unmap) + goto out_free; + + err = xsk_get_mmap_offsets(umem->fd, &off); + if (err) + goto out_free; + + munmap(ctx->fill->ring - off.fr.desc, off.fr.desc + umem->config.fill_size * + sizeof(__u64)); + munmap(ctx->comp->ring - off.cr.desc, off.cr.desc + umem->config.comp_size * + sizeof(__u64)); + +out_free: + list_del(&ctx->list); + free(ctx); +} + +static struct xsk_ctx *xsk_create_ctx(struct xsk_socket *xsk, + struct xsk_umem *umem, int ifindex, + __u32 queue_id, + struct xsk_ring_prod *fill, + struct xsk_ring_cons *comp) +{ + struct xsk_ctx *ctx; + int err; + + ctx = calloc(1, sizeof(*ctx)); + if (!ctx) + return NULL; + + if (!umem->fill_save) { + err = xsk_create_umem_rings(umem, xsk->fd, fill, comp); + if (err) { + free(ctx); + return NULL; + } + } else if (umem->fill_save != fill || umem->comp_save != comp) { + /* Copy over rings to new structs. */ + memcpy(fill, umem->fill_save, sizeof(*fill)); + memcpy(comp, umem->comp_save, sizeof(*comp)); + } + + ctx->ifindex = ifindex; + ctx->refcount = 1; + ctx->umem = umem; + ctx->queue_id = queue_id; + + ctx->fill = fill; + ctx->comp = comp; + list_add(&ctx->list, &umem->ctx_list); + return ctx; +} + +int xsk_socket__create_shared(struct xsk_socket **xsk_ptr, + int ifindex, + __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 *usr_config) +{ + bool unmap, rx_setup_done = false, tx_setup_done = false; + void *rx_map = NULL, *tx_map = NULL; + struct sockaddr_xdp sxdp = {}; + struct xdp_mmap_offsets off; + struct xsk_socket *xsk; + struct xsk_ctx *ctx; + int err; + + if (!umem || !xsk_ptr || !(rx || tx)) + return -EFAULT; + + unmap = umem->fill_save != fill; + + xsk = calloc(1, sizeof(*xsk)); + if (!xsk) + return -ENOMEM; + + err = xsk_set_xdp_socket_config(&xsk->config, usr_config); + if (err) + goto out_xsk_alloc; + + if (umem->refcount++ > 0) { + xsk->fd = socket(AF_XDP, SOCK_RAW | SOCK_CLOEXEC, 0); + if (xsk->fd < 0) { + err = -errno; + goto out_xsk_alloc; + } + } else { + xsk->fd = umem->fd; + rx_setup_done = umem->rx_ring_setup_done; + tx_setup_done = umem->tx_ring_setup_done; + } + + ctx = xsk_get_ctx(umem, ifindex, queue_id); + if (!ctx) { + if (!fill || !comp) { + err = -EFAULT; + goto out_socket; + } + + ctx = xsk_create_ctx(xsk, umem, ifindex, queue_id, fill, comp); + if (!ctx) { + err = -ENOMEM; + goto out_socket; + } + } + xsk->ctx = ctx; + + if (rx && !rx_setup_done) { + err = setsockopt(xsk->fd, SOL_XDP, XDP_RX_RING, + &xsk->config.rx_size, + sizeof(xsk->config.rx_size)); + if (err) { + err = -errno; + goto out_put_ctx; + } + if (xsk->fd == umem->fd) + umem->rx_ring_setup_done = true; + } + if (tx && !tx_setup_done) { + err = setsockopt(xsk->fd, SOL_XDP, XDP_TX_RING, + &xsk->config.tx_size, + sizeof(xsk->config.tx_size)); + if (err) { + err = -errno; + goto out_put_ctx; + } + if (xsk->fd == umem->fd) + umem->tx_ring_setup_done = true; + } + + err = xsk_get_mmap_offsets(xsk->fd, &off); + if (err) { + err = -errno; + goto out_put_ctx; + } + + if (rx) { + rx_map = mmap(NULL, off.rx.desc + + xsk->config.rx_size * sizeof(struct xdp_desc), + PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, + xsk->fd, XDP_PGOFF_RX_RING); + if (rx_map == MAP_FAILED) { + err = -errno; + goto out_put_ctx; + } + + rx->mask = xsk->config.rx_size - 1; + rx->size = xsk->config.rx_size; + rx->producer = rx_map + off.rx.producer; + rx->consumer = rx_map + off.rx.consumer; + rx->flags = rx_map + off.rx.flags; + rx->ring = rx_map + off.rx.desc; + rx->cached_prod = *rx->producer; + rx->cached_cons = *rx->consumer; + } + xsk->rx = rx; + + if (tx) { + tx_map = mmap(NULL, off.tx.desc + + xsk->config.tx_size * sizeof(struct xdp_desc), + PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, + xsk->fd, XDP_PGOFF_TX_RING); + if (tx_map == MAP_FAILED) { + err = -errno; + goto out_mmap_rx; + } + + tx->mask = xsk->config.tx_size - 1; + tx->size = xsk->config.tx_size; + tx->producer = tx_map + off.tx.producer; + tx->consumer = tx_map + off.tx.consumer; + tx->flags = tx_map + off.tx.flags; + tx->ring = tx_map + off.tx.desc; + tx->cached_prod = *tx->producer; + /* cached_cons is r->size bigger than the real consumer pointer + * See xsk_prod_nb_free + */ + tx->cached_cons = *tx->consumer + xsk->config.tx_size; + } + xsk->tx = tx; + + sxdp.sxdp_family = PF_XDP; + sxdp.sxdp_ifindex = ctx->ifindex; + sxdp.sxdp_queue_id = ctx->queue_id; + if (umem->refcount > 1) { + sxdp.sxdp_flags |= XDP_SHARED_UMEM; + sxdp.sxdp_shared_umem_fd = umem->fd; + } else { + sxdp.sxdp_flags = xsk->config.bind_flags; + } + + err = bind(xsk->fd, (struct sockaddr *)&sxdp, sizeof(sxdp)); + if (err) { + err = -errno; + goto out_mmap_tx; + } + + *xsk_ptr = xsk; + umem->fill_save = NULL; + umem->comp_save = NULL; + return 0; + +out_mmap_tx: + if (tx) + munmap(tx_map, off.tx.desc + + xsk->config.tx_size * sizeof(struct xdp_desc)); +out_mmap_rx: + if (rx) + munmap(rx_map, off.rx.desc + + xsk->config.rx_size * sizeof(struct xdp_desc)); +out_put_ctx: + xsk_put_ctx(ctx, unmap); +out_socket: + if (--umem->refcount) + close(xsk->fd); +out_xsk_alloc: + free(xsk); + return err; +} + +int xsk_socket__create(struct xsk_socket **xsk_ptr, int ifindex, + __u32 queue_id, struct xsk_umem *umem, + struct xsk_ring_cons *rx, struct xsk_ring_prod *tx, + const struct xsk_socket_config *usr_config) +{ + if (!umem) + return -EFAULT; + + return xsk_socket__create_shared(xsk_ptr, ifindex, queue_id, umem, + rx, tx, umem->fill_save, + umem->comp_save, usr_config); +} + +int xsk_umem__delete(struct xsk_umem *umem) +{ + struct xdp_mmap_offsets off; + int err; + + if (!umem) + return 0; + + if (umem->refcount) + return -EBUSY; + + err = xsk_get_mmap_offsets(umem->fd, &off); + if (!err && umem->fill_save && umem->comp_save) { + munmap(umem->fill_save->ring - off.fr.desc, + off.fr.desc + umem->config.fill_size * sizeof(__u64)); + munmap(umem->comp_save->ring - off.cr.desc, + off.cr.desc + umem->config.comp_size * sizeof(__u64)); + } + + close(umem->fd); + free(umem); + + return 0; +} + +void xsk_socket__delete(struct xsk_socket *xsk) +{ + size_t desc_sz = sizeof(struct xdp_desc); + struct xdp_mmap_offsets off; + struct xsk_umem *umem; + struct xsk_ctx *ctx; + int err; + + if (!xsk) + return; + + ctx = xsk->ctx; + umem = ctx->umem; + + xsk_put_ctx(ctx, true); + + err = xsk_get_mmap_offsets(xsk->fd, &off); + if (!err) { + if (xsk->rx) { + munmap(xsk->rx->ring - off.rx.desc, + off.rx.desc + xsk->config.rx_size * desc_sz); + } + if (xsk->tx) { + munmap(xsk->tx->ring - off.tx.desc, + off.tx.desc + xsk->config.tx_size * desc_sz); + } + } + + umem->refcount--; + /* Do not close an fd that also has an associated umem connected + * to it. + */ + if (xsk->fd != umem->fd) + close(xsk->fd); + free(xsk); +} |