diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/include/uapi/linux/ethtool.h | 51 | ||||
| -rw-r--r-- | tools/include/uapi/linux/if_xdp.h | 78 | ||||
| -rw-r--r-- | tools/lib/bpf/Build | 2 | ||||
| -rw-r--r-- | tools/lib/bpf/Makefile | 5 | ||||
| -rw-r--r-- | tools/lib/bpf/README.rst | 15 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.map | 6 | ||||
| -rw-r--r-- | tools/lib/bpf/xsk.c | 723 | ||||
| -rw-r--r-- | tools/lib/bpf/xsk.h | 203 |
8 files changed, 1080 insertions, 3 deletions
diff --git a/tools/include/uapi/linux/ethtool.h b/tools/include/uapi/linux/ethtool.h new file mode 100644 index 000000000000..c86c3e942df9 --- /dev/null +++ b/tools/include/uapi/linux/ethtool.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * ethtool.h: Defines for Linux ethtool. + * + * Copyright (C) 1998 David S. Miller (davem@redhat.com) + * Copyright 2001 Jeff Garzik <jgarzik@pobox.com> + * Portions Copyright 2001 Sun Microsystems (thockin@sun.com) + * Portions Copyright 2002 Intel (eli.kupermann@intel.com, + * christopher.leech@intel.com, + * scott.feldman@intel.com) + * Portions Copyright (C) Sun Microsystems 2008 + */ + +#ifndef _UAPI_LINUX_ETHTOOL_H +#define _UAPI_LINUX_ETHTOOL_H + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/if_ether.h> + +#define ETHTOOL_GCHANNELS 0x0000003c /* Get no of channels */ + +/** + * struct ethtool_channels - configuring number of network channel + * @cmd: ETHTOOL_{G,S}CHANNELS + * @max_rx: Read only. Maximum number of receive channel the driver support. + * @max_tx: Read only. Maximum number of transmit channel the driver support. + * @max_other: Read only. Maximum number of other channel the driver support. + * @max_combined: Read only. Maximum number of combined channel the driver + * support. Set of queues RX, TX or other. + * @rx_count: Valid values are in the range 1 to the max_rx. + * @tx_count: Valid values are in the range 1 to the max_tx. + * @other_count: Valid values are in the range 1 to the max_other. + * @combined_count: Valid values are in the range 1 to the max_combined. + * + * This can be used to configure RX, TX and other channels. + */ + +struct ethtool_channels { + __u32 cmd; + __u32 max_rx; + __u32 max_tx; + __u32 max_other; + __u32 max_combined; + __u32 rx_count; + __u32 tx_count; + __u32 other_count; + __u32 combined_count; +}; + +#endif /* _UAPI_LINUX_ETHTOOL_H */ diff --git a/tools/include/uapi/linux/if_xdp.h b/tools/include/uapi/linux/if_xdp.h new file mode 100644 index 000000000000..caed8b1614ff --- /dev/null +++ b/tools/include/uapi/linux/if_xdp.h @@ -0,0 +1,78 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * if_xdp: XDP socket user-space interface + * Copyright(c) 2018 Intel Corporation. + * + * Author(s): Björn Töpel <bjorn.topel@intel.com> + * Magnus Karlsson <magnus.karlsson@intel.com> + */ + +#ifndef _LINUX_IF_XDP_H +#define _LINUX_IF_XDP_H + +#include <linux/types.h> + +/* Options for the sxdp_flags field */ +#define XDP_SHARED_UMEM (1 << 0) +#define XDP_COPY (1 << 1) /* Force copy-mode */ +#define XDP_ZEROCOPY (1 << 2) /* Force zero-copy mode */ + +struct sockaddr_xdp { + __u16 sxdp_family; + __u16 sxdp_flags; + __u32 sxdp_ifindex; + __u32 sxdp_queue_id; + __u32 sxdp_shared_umem_fd; +}; + +struct xdp_ring_offset { + __u64 producer; + __u64 consumer; + __u64 desc; +}; + +struct xdp_mmap_offsets { + struct xdp_ring_offset rx; + struct xdp_ring_offset tx; + struct xdp_ring_offset fr; /* Fill */ + struct xdp_ring_offset cr; /* Completion */ +}; + +/* XDP socket options */ +#define XDP_MMAP_OFFSETS 1 +#define XDP_RX_RING 2 +#define XDP_TX_RING 3 +#define XDP_UMEM_REG 4 +#define XDP_UMEM_FILL_RING 5 +#define XDP_UMEM_COMPLETION_RING 6 +#define XDP_STATISTICS 7 + +struct xdp_umem_reg { + __u64 addr; /* Start of packet data area */ + __u64 len; /* Length of packet data area */ + __u32 chunk_size; + __u32 headroom; +}; + +struct xdp_statistics { + __u64 rx_dropped; /* Dropped for reasons other than invalid desc */ + __u64 rx_invalid_descs; /* Dropped due to invalid descriptor */ + __u64 tx_invalid_descs; /* Dropped due to invalid descriptor */ +}; + +/* Pgoff for mmaping the rings */ +#define XDP_PGOFF_RX_RING 0 +#define XDP_PGOFF_TX_RING 0x80000000 +#define XDP_UMEM_PGOFF_FILL_RING 0x100000000ULL +#define XDP_UMEM_PGOFF_COMPLETION_RING 0x180000000ULL + +/* Rx/Tx descriptor */ +struct xdp_desc { + __u64 addr; + __u32 len; + __u32 options; +}; + +/* UMEM descriptor is __u64 */ + +#endif /* _LINUX_IF_XDP_H */ diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build index bfd9bfc82c3b..ee9d5362f35b 100644 --- a/tools/lib/bpf/Build +++ b/tools/lib/bpf/Build @@ -1 +1 @@ -libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o netlink.o bpf_prog_linfo.o libbpf_probes.o +libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o netlink.o bpf_prog_linfo.o libbpf_probes.o xsk.o diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile index 847916273696..761691bd72ad 100644 --- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -164,6 +164,9 @@ $(BPF_IN): force elfdep bpfdep @(test -f ../../include/uapi/linux/if_link.h -a -f ../../../include/uapi/linux/if_link.h && ( \ (diff -B ../../include/uapi/linux/if_link.h ../../../include/uapi/linux/if_link.h >/dev/null) || \ echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_link.h' differs from latest version at 'include/uapi/linux/if_link.h'" >&2 )) || true + @(test -f ../../include/uapi/linux/if_xdp.h -a -f ../../../include/uapi/linux/if_xdp.h && ( \ + (diff -B ../../include/uapi/linux/if_xdp.h ../../../include/uapi/linux/if_xdp.h >/dev/null) || \ + echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) || true $(Q)$(MAKE) $(build)=libbpf $(OUTPUT)libbpf.so: $(BPF_IN) @@ -174,7 +177,7 @@ $(OUTPUT)libbpf.a: $(BPF_IN) $(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^ $(OUTPUT)test_libbpf: test_libbpf.cpp $(OUTPUT)libbpf.a - $(QUIET_LINK)$(CXX) $^ -lelf -o $@ + $(QUIET_LINK)$(CXX) $(INCLUDES) $^ -lelf -o $@ check: check_abi diff --git a/tools/lib/bpf/README.rst b/tools/lib/bpf/README.rst index 607aae40f4ed..5788479384ca 100644 --- a/tools/lib/bpf/README.rst +++ b/tools/lib/bpf/README.rst @@ -9,7 +9,7 @@ described here. It's recommended to follow these conventions whenever a new function or type is added to keep libbpf API clean and consistent. All types and functions provided by libbpf API should have one of the -following prefixes: ``bpf_``, ``btf_``, ``libbpf_``. +following prefixes: ``bpf_``, ``btf_``, ``libbpf_``, ``xsk_``. System call wrappers -------------------- @@ -62,6 +62,19 @@ Auxiliary functions and types that don't fit well in any of categories described above should have ``libbpf_`` prefix, e.g. ``libbpf_get_error`` or ``libbpf_prog_type_by_name``. +AF_XDP functions +------------------- + +AF_XDP functions should have an ``xsk_`` prefix, e.g. +``xsk_umem__get_data`` or ``xsk_umem__create``. The interface consists +of both low-level ring access functions and high-level configuration +functions. These can be mixed and matched. Note that these functions +are not reentrant for performance reasons. + +Please take a look at Documentation/networking/af_xdp.rst in the Linux +kernel source tree on how to use XDP sockets and for some common +mistakes in case you do not get any traffic up to user space. + libbpf ABI ========== diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 99dfa710c818..778a26702a70 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -147,4 +147,10 @@ LIBBPF_0.0.2 { btf_ext__new; btf_ext__reloc_func_info; btf_ext__reloc_line_info; + xsk_umem__create; + xsk_socket__create; + xsk_umem__delete; + xsk_socket__delete; + xsk_umem__fd; + xsk_socket__fd; } LIBBPF_0.0.1; diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c new file mode 100644 index 000000000000..f98ac82c9aea --- /dev/null +++ b/tools/lib/bpf/xsk.c @@ -0,0 +1,723 @@ +// 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_packet.h> +#include <linux/if_xdp.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.h" +#include "libbpf.h" +#include "libbpf_util.h" +#include "xsk.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 + +struct xsk_umem { + struct xsk_ring_prod *fill; + struct xsk_ring_cons *comp; + char *umem_area; + struct xsk_umem_config config; + int fd; + int refcount; +}; + +struct xsk_socket { + struct xsk_ring_cons *rx; + struct xsk_ring_prod *tx; + __u64 outstanding_tx; + struct xsk_umem *umem; + struct xsk_socket_config config; + int fd; + int xsks_map; + int ifindex; + int prog_fd; + int qidconf_map_fd; + int xsks_map_fd; + __u32 queue_id; + char ifname[IFNAMSIZ]; +}; + +struct xsk_nl_info { + bool xdp_prog_attached; + int ifindex; + int fd; +}; + +/* For 32-bit systems, we need to use mmap2 as the offsets are 64-bit. + * Unfortunately, it is not part of glibc. + */ +static inline void *xsk_mmap(void *addr, size_t length, int prot, int flags, + int fd, __u64 offset) +{ +#ifdef __NR_mmap2 + unsigned int page_shift = __builtin_ffs(getpagesize()) - 1; + long ret = syscall(__NR_mmap2, addr, length, prot, flags, fd, + (off_t)(offset >> page_shift)); + + return (void *)ret; +#else + return mmap(addr, length, prot, flags, fd, offset); +#endif +} + +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; + 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; +} + +static void 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->libbpf_flags = 0; + cfg->xdp_flags = 0; + cfg->bind_flags = 0; + return; + } + + cfg->rx_size = usr_cfg->rx_size; + cfg->tx_size = usr_cfg->tx_size; + cfg->libbpf_flags = usr_cfg->libbpf_flags; + cfg->xdp_flags = usr_cfg->xdp_flags; + cfg->bind_flags = usr_cfg->bind_flags; +} + +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_mmap_offsets off; + struct xdp_umem_reg mr; + struct xsk_umem *umem; + socklen_t optlen; + void *map; + 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, 0); + if (umem->fd < 0) { + err = -errno; + goto out_umem_alloc; + } + + umem->umem_area = umem_area; + xsk_set_umem_config(&umem->config, usr_config); + + mr.addr = (uintptr_t)umem_area; + mr.len = size; + mr.chunk_size = umem->config.frame_size; + mr.headroom = umem->config.frame_headroom; + + err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_REG, &mr, sizeof(mr)); + if (err) { + err = -errno; + goto out_socket; + } + err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_FILL_RING, + &umem->config.fill_size, + sizeof(umem->config.fill_size)); + if (err) { + err = -errno; + goto out_socket; + } + err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_COMPLETION_RING, + &umem->config.comp_size, + sizeof(umem->config.comp_size)); + if (err) { + err = -errno; + goto out_socket; + } + + optlen = sizeof(off); + err = getsockopt(umem->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen); + if (err) { + err = -errno; + goto out_socket; + } + + map = xsk_mmap(NULL, off.fr.desc + + umem->config.fill_size * sizeof(__u64), + PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, + umem->fd, XDP_UMEM_PGOFF_FILL_RING); + if (map == MAP_FAILED) { + err = -errno; + goto out_socket; + } + + umem->fill = fill; + 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->ring = map + off.fr.desc; + fill->cached_cons = umem->config.fill_size; + + map = xsk_mmap(NULL, + off.cr.desc + umem->config.comp_size * sizeof(__u64), + PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, + umem->fd, XDP_UMEM_PGOFF_COMPLETION_RING); + if (map == MAP_FAILED) { + err = -errno; + goto out_mmap; + } + + umem->comp = comp; + 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->ring = map + off.cr.desc; + + *umem_ptr = umem; + return 0; + +out_mmap: + munmap(umem->fill, + off.fr.desc + umem->config.fill_size * sizeof(__u64)); +out_socket: + close(umem->fd); +out_umem_alloc: + free(umem); + return err; +} + +static int xsk_load_xdp_prog(struct xsk_socket *xsk) +{ + char bpf_log_buf[BPF_LOG_BUF_SIZE]; + int err, prog_fd; + + /* This is the C-program: + * SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx) + * { + * int *qidconf, index = ctx->rx_queue_index; + * + * // A set entry here means that the correspnding queue_id + * // has an active AF_XDP socket bound to it. + * qidconf = bpf_map_lookup_elem(&qidconf_map, &index); + * if (!qidconf) + * return XDP_ABORTED; + * + * if (*qidconf) + * return bpf_redirect_map(&xsks_map, index, 0); + * + * return XDP_PASS; + * } + */ + struct bpf_insn prog[] = { + /* r1 = *(u32 *)(r1 + 16) */ + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 16), + /* *(u32 *)(r10 - 4) = r1 */ + BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_1, -4), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), + BPF_LD_MAP_FD(BPF_REG_1, xsk->qidconf_map_fd), + BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_MOV32_IMM(BPF_REG_0, 0), + /* if r1 == 0 goto +8 */ + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 8), + BPF_MOV32_IMM(BPF_REG_0, 2), + /* r1 = *(u32 *)(r1 + 0) */ + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 0), + /* if r1 == 0 goto +5 */ + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 5), + /* r2 = *(u32 *)(r10 - 4) */ + BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd), + BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_10, -4), + BPF_MOV32_IMM(BPF_REG_3, 0), + BPF_EMIT_CALL(BPF_FUNC_redirect_map), + /* The jumps are to this instruction */ + BPF_EXIT_INSN(), + }; + size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn); + + prog_fd = bpf_load_program(BPF_PROG_TYPE_XDP, prog, insns_cnt, + "LGPL-2.1 or BSD-2-Clause", 0, bpf_log_buf, + BPF_LOG_BUF_SIZE); + if (prog_fd < 0) { + pr_warning("BPF log buffer:\n%s", bpf_log_buf); + return prog_fd; + } + + err = bpf_set_link_xdp_fd(xsk->ifindex, prog_fd, xsk->config.xdp_flags); + if (err) { + close(prog_fd); + return err; + } + + xsk->prog_fd = prog_fd; + return 0; +} + +static int xsk_get_max_queues(struct xsk_socket *xsk) +{ + struct ethtool_channels channels; + struct ifreq ifr; + int fd, err, ret; + + fd = socket(AF_INET, SOCK_DGRAM, 0); + if (fd < 0) + return -errno; + + channels.cmd = ETHTOOL_GCHANNELS; + ifr.ifr_data = (void *)&channels; + strncpy(ifr.ifr_name, xsk->ifname, IFNAMSIZ); + err = ioctl(fd, SIOCETHTOOL, &ifr); + if (err && errno != EOPNOTSUPP) { + ret = -errno; + goto out; + } + + if (channels.max_combined == 0 || errno == EOPNOTSUPP) + /* If the device says it has no channels, then all traffic + * is sent to a single stream, so max queues = 1. + */ + ret = 1; + else + ret = channels.max_combined; + +out: + close(fd); + return ret; +} + +static int xsk_create_bpf_maps(struct xsk_socket *xsk) +{ + int max_queues; + int fd; + + max_queues = xsk_get_max_queues(xsk); + if (max_queues < 0) + return max_queues; + + fd = bpf_create_map_name(BPF_MAP_TYPE_ARRAY, "qidconf_map", + sizeof(int), sizeof(int), max_queues, 0); + if (fd < 0) + return fd; + xsk->qidconf_map_fd = fd; + + fd = bpf_create_map_name(BPF_MAP_TYPE_XSKMAP, "xsks_map", + sizeof(int), sizeof(int), max_queues, 0); + if (fd < 0) { + close(xsk->qidconf_map_fd); + return fd; + } + xsk->xsks_map_fd = fd; + + return 0; +} + +static void xsk_delete_bpf_maps(struct xsk_socket *xsk) +{ + close(xsk->qidconf_map_fd); + close(xsk->xsks_map_fd); +} + +static int xsk_update_bpf_maps(struct xsk_socket *xsk, int qidconf_value, + int xsks_value) +{ + bool qidconf_map_updated = false, xsks_map_updated = false; + struct bpf_prog_info prog_info = {}; + __u32 prog_len = sizeof(prog_info); + struct bpf_map_info map_info; + __u32 map_len = sizeof(map_info); + __u32 *map_ids; + int reset_value = 0; + __u32 num_maps; + unsigned int i; + int err; + + err = bpf_obj_get_info_by_fd(xsk->prog_fd, &prog_info, &prog_len); + if (err) + return err; + + num_maps = prog_info.nr_map_ids; + + map_ids = calloc(prog_info.nr_map_ids, sizeof(*map_ids)); + if (!map_ids) + return -ENOMEM; + + memset(&prog_info, 0, prog_len); + prog_info.nr_map_ids = num_maps; + prog_info.map_ids = (__u64)(unsigned long)map_ids; + + err = bpf_obj_get_info_by_fd(xsk->prog_fd, &prog_info, &prog_len); + if (err) + goto out_map_ids; + + for (i = 0; i < prog_info.nr_map_ids; i++) { + int fd; + + fd = bpf_map_get_fd_by_id(map_ids[i]); + if (fd < 0) { + err = -errno; + goto out_maps; + } + + err = bpf_obj_get_info_by_fd(fd, &map_info, &map_len); + if (err) + goto out_maps; + + if (!strcmp(map_info.name, "qidconf_map")) { + err = bpf_map_update_elem(fd, &xsk->queue_id, + &qidconf_value, 0); + if (err) + goto out_maps; + qidconf_map_updated = true; + xsk->qidconf_map_fd = fd; + } else if (!strcmp(map_info.name, "xsks_map")) { + err = bpf_map_update_elem(fd, &xsk->queue_id, + &xsks_value, 0); + if (err) + goto out_maps; + xsks_map_updated = true; + xsk->xsks_map_fd = fd; + } + + if (qidconf_map_updated && xsks_map_updated) + break; + } + + if (!(qidconf_map_updated && xsks_map_updated)) { + err = -ENOENT; + goto out_maps; + } + + err = 0; + goto out_success; + +out_maps: + if (qidconf_map_updated) + (void)bpf_map_update_elem(xsk->qidconf_map_fd, &xsk->queue_id, + &reset_value, 0); + if (xsks_map_updated) + (void)bpf_map_update_elem(xsk->xsks_map_fd, &xsk->queue_id, + &reset_value, 0); +out_success: + if (qidconf_map_updated) + close(xsk->qidconf_map_fd); + if (xsks_map_updated) + close(xsk->xsks_map_fd); +out_map_ids: + free(map_ids); + return err; +} + +static int xsk_setup_xdp_prog(struct xsk_socket *xsk) +{ + bool prog_attached = false; + __u32 prog_id = 0; + int err; + + err = bpf_get_link_xdp_id(xsk->ifindex, &prog_id, + xsk->config.xdp_flags); + if (err) + return err; + + if (!prog_id) { + prog_attached = true; + err = xsk_create_bpf_maps(xsk); + if (err) + return err; + + err = xsk_load_xdp_prog(xsk); + if (err) + goto out_maps; + } else { + xsk->prog_fd = bpf_prog_get_fd_by_id(prog_id); + } + + err = xsk_update_bpf_maps(xsk, true, xsk->fd); + if (err) + goto out_load; + + return 0; + +out_load: + if (prog_attached) + close(xsk->prog_fd); +out_maps: + if (prog_attached) + xsk_delete_bpf_maps(xsk); + return err; +} + +int xsk_socket__create(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, + const struct xsk_socket_config *usr_config) +{ + struct sockaddr_xdp sxdp = {}; + struct xdp_mmap_offsets off; + struct xsk_socket *xsk; + socklen_t optlen; + void *map; + int err; + + if (!umem || !xsk_ptr || !rx || !tx) + return -EFAULT; + + if (umem->refcount) { + pr_warning("Error: shared umems not supported by libbpf.\n"); + return -EBUSY; + } + + xsk = calloc(1, sizeof(*xsk)); + if (!xsk) + return -ENOMEM; + + if (umem->refcount++ > 0) { + xsk->fd = socket(AF_XDP, SOCK_RAW, 0); + if (xsk->fd < 0) { + err = -errno; + goto out_xsk_alloc; + } + } else { + xsk->fd = umem->fd; + } + + xsk->outstanding_tx = 0; + xsk->queue_id = queue_id; + xsk->umem = umem; + xsk->ifindex = if_nametoindex(ifname); + if (!xsk->ifindex) { + err = -errno; + goto out_socket; + } + strncpy(xsk->ifname, ifname, IFNAMSIZ); + + xsk_set_xdp_socket_config(&xsk->config, usr_config); + + if (rx) { + err = setsockopt(xsk->fd, SOL_XDP, XDP_RX_RING, + &xsk->config.rx_size, + sizeof(xsk->config.rx_size)); + if (err) { + err = -errno; + goto out_socket; + } + } + if (tx) { + err = setsockopt(xsk->fd, SOL_XDP, XDP_TX_RING, + &xsk->config.tx_size, + sizeof(xsk->config.tx_size)); + if (err) { + err = -errno; + goto out_socket; + } + } + + optlen = sizeof(off); + err = getsockopt(xsk->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen); + if (err) { + err = -errno; + goto out_socket; + } + + if (rx) { + map = xsk_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 (map == MAP_FAILED) { + err = -errno; + goto out_socket; + } + + rx->mask = xsk->config.rx_size - 1; + rx->size = xsk->config.rx_size; + rx->producer = map + off.rx.producer; + rx->consumer = map + off.rx.consumer; + rx->ring = map + off.rx.desc; + } + xsk->rx = rx; + + if (tx) { + map = xsk_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 (map == MAP_FAILED) { + err = -errno; + goto out_mmap_rx; + } + + tx->mask = xsk->config.tx_size - 1; + tx->size = xsk->config.tx_size; + tx->producer = map + off.tx.producer; + tx->consumer = map + off.tx.consumer; + tx->ring = map + off.tx.desc; + tx->cached_cons = xsk->config.tx_size; + } + xsk->tx = tx; + + sxdp.sxdp_family = PF_XDP; + sxdp.sxdp_ifindex = xsk->ifindex; + sxdp.sxdp_queue_id = xsk->queue_id; + sxdp.sxdp_flags = xsk->config.bind_flags; + + err = bind(xsk->fd, (struct sockaddr *)&sxdp, sizeof(sxdp)); + if (err) { + err = -errno; + goto out_mmap_tx; + } + + if (!(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) { + err = xsk_setup_xdp_prog(xsk); + if (err) + goto out_mmap_tx; + } + + *xsk_ptr = xsk; + return 0; + +out_mmap_tx: + if (tx) + munmap(xsk->tx, + off.tx.desc + + xsk->config.tx_size * sizeof(struct xdp_desc)); +out_mmap_rx: + if (rx) + munmap(xsk->rx, + off.rx.desc + + xsk->config.rx_size * sizeof(struct xdp_desc)); +out_socket: + if (--umem->refcount) + close(xsk->fd); +out_xsk_alloc: + free(xsk); + return err; +} + +int xsk_umem__delete(struct xsk_umem *umem) +{ + struct xdp_mmap_offsets off; + socklen_t optlen; + int err; + + if (!umem) + return 0; + + if (umem->refcount) + return -EBUSY; + + optlen = sizeof(off); + err = getsockopt(umem->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen); + if (!err) { + munmap(umem->fill->ring, + off.fr.desc + umem->config.fill_size * sizeof(__u64)); + munmap(umem->comp->ring, + off.cr.desc + umem->config.comp_size * sizeof(__u64)); + } + + close(umem->fd); + free(umem); + + return 0; +} + +void xsk_socket__delete(struct xsk_socket *xsk) +{ + struct xdp_mmap_offsets off; + socklen_t optlen; + int err; + + if (!xsk) + return; + + (void)xsk_update_bpf_maps(xsk, 0, 0); + + optlen = sizeof(off); + err = getsockopt(xsk->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen); + if (!err) { + if (xsk->rx) + munmap(xsk->rx->ring, + off.rx.desc + + xsk->config.rx_size * sizeof(struct xdp_desc)); + if (xsk->tx) + munmap(xsk->tx->ring, + off.tx.desc + + xsk->config.tx_size * sizeof(struct xdp_desc)); + } + + xsk->umem->refcount--; + /* Do not close an fd that also has an associated umem connected + * to it. + */ + if (xsk->fd != xsk->umem->fd) + close(xsk->fd); + free(xsk); +} diff --git a/tools/lib/bpf/xsk.h b/tools/lib/bpf/xsk.h new file mode 100644 index 000000000000..a497f00e2962 --- /dev/null +++ b/tools/lib/bpf/xsk.h @@ -0,0 +1,203 @@ +/* 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" + +#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; \ +} + +DEFINE_XSK_RING(xsk_ring_prod); +DEFINE_XSK_RING(xsk_ring_cons); + +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 __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 size_t xsk_ring_prod__reserve(struct xsk_ring_prod *prod, + size_t nb, __u32 *idx) +{ + if (unlikely(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, size_t nb) +{ + /* Make sure everything has been written to the ring before signalling + * this to the kernel. + */ + smp_wmb(); + + *prod->producer += nb; +} + +static inline size_t xsk_ring_cons__peek(struct xsk_ring_cons *cons, + size_t nb, __u32 *idx) +{ + size_t entries = xsk_cons_nb_avail(cons, nb); + + if (likely(entries > 0)) { + /* Make sure we do not speculatively read the data before + * we have received the packet buffers from the ring. + */ + smp_rmb(); + + *idx = cons->cached_cons; + cons->cached_cons += entries; + } + + return entries; +} + +static inline void xsk_ring_cons__release(struct xsk_ring_cons *cons, size_t nb) +{ + *cons->consumer += nb; +} + +static inline void *xsk_umem__get_data(void *umem_area, __u64 addr) +{ + return &((char *)umem_area)[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 11 /* 2048 bytes */ +#define XSK_UMEM__DEFAULT_FRAME_SIZE (1 << XSK_UMEM__DEFAULT_FRAME_SHIFT) +#define XSK_UMEM__DEFAULT_FRAME_HEADROOM 0 + +struct xsk_umem_config { + __u32 fill_size; + __u32 comp_size; + __u32 frame_size; + __u32 frame_headroom; +}; + +/* 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_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); + +/* 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 */ |