1 /* 2 * eBPF RSS loader 3 * 4 * Developed by Daynix Computing LTD (http://www.daynix.com) 5 * 6 * Authors: 7 * Andrew Melnychenko <andrew@daynix.com> 8 * Yuri Benditovich <yuri.benditovich@daynix.com> 9 * 10 * This work is licensed under the terms of the GNU GPL, version 2. See 11 * the COPYING file in the top-level directory. 12 */ 13 14 #include "qemu/osdep.h" 15 #include "qemu/error-report.h" 16 17 #include <bpf/libbpf.h> 18 #include <bpf/bpf.h> 19 20 #include "hw/virtio/virtio-net.h" /* VIRTIO_NET_RSS_MAX_TABLE_LEN */ 21 22 #include "ebpf/ebpf_rss.h" 23 #include "ebpf/rss.bpf.skeleton.h" 24 #include "trace.h" 25 26 void ebpf_rss_init(struct EBPFRSSContext *ctx) 27 { 28 if (ctx != NULL) { 29 ctx->obj = NULL; 30 } 31 } 32 33 bool ebpf_rss_is_loaded(struct EBPFRSSContext *ctx) 34 { 35 return ctx != NULL && ctx->obj != NULL; 36 } 37 38 bool ebpf_rss_load(struct EBPFRSSContext *ctx) 39 { 40 struct rss_bpf *rss_bpf_ctx; 41 42 if (ctx == NULL) { 43 return false; 44 } 45 46 rss_bpf_ctx = rss_bpf__open(); 47 if (rss_bpf_ctx == NULL) { 48 trace_ebpf_error("eBPF RSS", "can not open eBPF RSS object"); 49 goto error; 50 } 51 52 bpf_program__set_socket_filter(rss_bpf_ctx->progs.tun_rss_steering_prog); 53 54 if (rss_bpf__load(rss_bpf_ctx)) { 55 trace_ebpf_error("eBPF RSS", "can not load RSS program"); 56 goto error; 57 } 58 59 ctx->obj = rss_bpf_ctx; 60 ctx->program_fd = bpf_program__fd( 61 rss_bpf_ctx->progs.tun_rss_steering_prog); 62 ctx->map_configuration = bpf_map__fd( 63 rss_bpf_ctx->maps.tap_rss_map_configurations); 64 ctx->map_indirections_table = bpf_map__fd( 65 rss_bpf_ctx->maps.tap_rss_map_indirection_table); 66 ctx->map_toeplitz_key = bpf_map__fd( 67 rss_bpf_ctx->maps.tap_rss_map_toeplitz_key); 68 69 return true; 70 error: 71 rss_bpf__destroy(rss_bpf_ctx); 72 ctx->obj = NULL; 73 74 return false; 75 } 76 77 static bool ebpf_rss_set_config(struct EBPFRSSContext *ctx, 78 struct EBPFRSSConfig *config) 79 { 80 uint32_t map_key = 0; 81 82 if (!ebpf_rss_is_loaded(ctx)) { 83 return false; 84 } 85 if (bpf_map_update_elem(ctx->map_configuration, 86 &map_key, config, 0) < 0) { 87 return false; 88 } 89 return true; 90 } 91 92 static bool ebpf_rss_set_indirections_table(struct EBPFRSSContext *ctx, 93 uint16_t *indirections_table, 94 size_t len) 95 { 96 uint32_t i = 0; 97 98 if (!ebpf_rss_is_loaded(ctx) || indirections_table == NULL || 99 len > VIRTIO_NET_RSS_MAX_TABLE_LEN) { 100 return false; 101 } 102 103 for (; i < len; ++i) { 104 if (bpf_map_update_elem(ctx->map_indirections_table, &i, 105 indirections_table + i, 0) < 0) { 106 return false; 107 } 108 } 109 return true; 110 } 111 112 static bool ebpf_rss_set_toepliz_key(struct EBPFRSSContext *ctx, 113 uint8_t *toeplitz_key) 114 { 115 uint32_t map_key = 0; 116 117 /* prepare toeplitz key */ 118 uint8_t toe[VIRTIO_NET_RSS_MAX_KEY_SIZE] = {}; 119 120 if (!ebpf_rss_is_loaded(ctx) || toeplitz_key == NULL) { 121 return false; 122 } 123 memcpy(toe, toeplitz_key, VIRTIO_NET_RSS_MAX_KEY_SIZE); 124 *(uint32_t *)toe = ntohl(*(uint32_t *)toe); 125 126 if (bpf_map_update_elem(ctx->map_toeplitz_key, &map_key, toe, 127 0) < 0) { 128 return false; 129 } 130 return true; 131 } 132 133 bool ebpf_rss_set_all(struct EBPFRSSContext *ctx, struct EBPFRSSConfig *config, 134 uint16_t *indirections_table, uint8_t *toeplitz_key) 135 { 136 if (!ebpf_rss_is_loaded(ctx) || config == NULL || 137 indirections_table == NULL || toeplitz_key == NULL) { 138 return false; 139 } 140 141 if (!ebpf_rss_set_config(ctx, config)) { 142 return false; 143 } 144 145 if (!ebpf_rss_set_indirections_table(ctx, indirections_table, 146 config->indirections_len)) { 147 return false; 148 } 149 150 if (!ebpf_rss_set_toepliz_key(ctx, toeplitz_key)) { 151 return false; 152 } 153 154 return true; 155 } 156 157 void ebpf_rss_unload(struct EBPFRSSContext *ctx) 158 { 159 if (!ebpf_rss_is_loaded(ctx)) { 160 return; 161 } 162 163 rss_bpf__destroy(ctx->obj); 164 ctx->obj = NULL; 165 } 166