| 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | /* Copyright (c) 2013-2018, 2021, The Linux Foundation. All rights reserved. |
| 3 | * |
| 4 | * RMNET Data MAP protocol |
| 5 | */ |
| 6 | |
| 7 | #include <linux/netdevice.h> |
| 8 | #include <linux/ip.h> |
| 9 | #include <linux/ipv6.h> |
| 10 | #include <net/ip6_checksum.h> |
| 11 | #include <linux/bitfield.h> |
| 12 | #include "rmnet_config.h" |
| 13 | #include "rmnet_map.h" |
| 14 | #include "rmnet_private.h" |
| 15 | #include "rmnet_vnd.h" |
| 16 | |
| 17 | #define RMNET_MAP_DEAGGR_SPACING 64 |
| 18 | #define RMNET_MAP_DEAGGR_HEADROOM (RMNET_MAP_DEAGGR_SPACING / 2) |
| 19 | |
| 20 | static __sum16 *rmnet_map_get_csum_field(unsigned char protocol, |
| 21 | const void *txporthdr) |
| 22 | { |
| 23 | if (protocol == IPPROTO_TCP) |
| 24 | return &((struct tcphdr *)txporthdr)->check; |
| 25 | |
| 26 | if (protocol == IPPROTO_UDP) |
| 27 | return &((struct udphdr *)txporthdr)->check; |
| 28 | |
| 29 | return NULL; |
| 30 | } |
| 31 | |
| 32 | static int |
| 33 | rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb, |
| 34 | struct rmnet_map_dl_csum_trailer *csum_trailer, |
| 35 | struct rmnet_priv *priv) |
| 36 | { |
| 37 | struct iphdr *ip4h = (struct iphdr *)skb->data; |
| 38 | void *txporthdr = skb->data + ip4h->ihl * 4; |
| 39 | __sum16 *csum_field, pseudo_csum; |
| 40 | __sum16 ip_payload_csum; |
| 41 | |
| 42 | /* Computing the checksum over just the IPv4 header--including its |
| 43 | * checksum field--should yield 0. If it doesn't, the IP header |
| 44 | * is bad, so return an error and let the IP layer drop it. |
| 45 | */ |
| 46 | if (ip_fast_csum(iph: ip4h, ihl: ip4h->ihl)) { |
| 47 | priv->stats.csum_ip4_header_bad++; |
| 48 | return -EINVAL; |
| 49 | } |
| 50 | |
| 51 | /* We don't support checksum offload on IPv4 fragments */ |
| 52 | if (ip_is_fragment(iph: ip4h)) { |
| 53 | priv->stats.csum_fragmented_pkt++; |
| 54 | return -EOPNOTSUPP; |
| 55 | } |
| 56 | |
| 57 | /* Checksum offload is only supported for UDP and TCP protocols */ |
| 58 | csum_field = rmnet_map_get_csum_field(protocol: ip4h->protocol, txporthdr); |
| 59 | if (!csum_field) { |
| 60 | priv->stats.csum_err_invalid_transport++; |
| 61 | return -EPROTONOSUPPORT; |
| 62 | } |
| 63 | |
| 64 | /* RFC 768: UDP checksum is optional for IPv4, and is 0 if unused */ |
| 65 | if (!*csum_field && ip4h->protocol == IPPROTO_UDP) { |
| 66 | priv->stats.csum_skipped++; |
| 67 | return 0; |
| 68 | } |
| 69 | |
| 70 | /* The checksum value in the trailer is computed over the entire |
| 71 | * IP packet, including the IP header and payload. To derive the |
| 72 | * transport checksum from this, we first subract the contribution |
| 73 | * of the IP header from the trailer checksum. We then add the |
| 74 | * checksum computed over the pseudo header. |
| 75 | * |
| 76 | * We verified above that the IP header contributes zero to the |
| 77 | * trailer checksum. Therefore the checksum in the trailer is |
| 78 | * just the checksum computed over the IP payload. |
| 79 | |
| 80 | * If the IP payload arrives intact, adding the pseudo header |
| 81 | * checksum to the IP payload checksum will yield 0xffff (negative |
| 82 | * zero). This means the trailer checksum and the pseudo checksum |
| 83 | * are additive inverses of each other. Put another way, the |
| 84 | * message passes the checksum test if the trailer checksum value |
| 85 | * is the negated pseudo header checksum. |
| 86 | * |
| 87 | * Knowing this, we don't even need to examine the transport |
| 88 | * header checksum value; it is already accounted for in the |
| 89 | * checksum value found in the trailer. |
| 90 | */ |
| 91 | ip_payload_csum = csum_trailer->csum_value; |
| 92 | |
| 93 | pseudo_csum = csum_tcpudp_magic(saddr: ip4h->saddr, daddr: ip4h->daddr, |
| 94 | ntohs(ip4h->tot_len) - ip4h->ihl * 4, |
| 95 | proto: ip4h->protocol, sum: 0); |
| 96 | |
| 97 | /* The cast is required to ensure only the low 16 bits are examined */ |
| 98 | if (ip_payload_csum != (__sum16)~pseudo_csum) { |
| 99 | priv->stats.csum_validation_failed++; |
| 100 | return -EINVAL; |
| 101 | } |
| 102 | |
| 103 | priv->stats.csum_ok++; |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | #if IS_ENABLED(CONFIG_IPV6) |
| 108 | static int |
| 109 | rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, |
| 110 | struct rmnet_map_dl_csum_trailer *csum_trailer, |
| 111 | struct rmnet_priv *priv) |
| 112 | { |
| 113 | struct ipv6hdr *ip6h = (struct ipv6hdr *)skb->data; |
| 114 | void *txporthdr = skb->data + sizeof(*ip6h); |
| 115 | __sum16 *csum_field, pseudo_csum; |
| 116 | __sum16 ip6_payload_csum; |
| 117 | __be16 ; |
| 118 | |
| 119 | /* Checksum offload is only supported for UDP and TCP protocols; |
| 120 | * the packet cannot include any IPv6 extension headers |
| 121 | */ |
| 122 | csum_field = rmnet_map_get_csum_field(protocol: ip6h->nexthdr, txporthdr); |
| 123 | if (!csum_field) { |
| 124 | priv->stats.csum_err_invalid_transport++; |
| 125 | return -EPROTONOSUPPORT; |
| 126 | } |
| 127 | |
| 128 | /* The checksum value in the trailer is computed over the entire |
| 129 | * IP packet, including the IP header and payload. To derive the |
| 130 | * transport checksum from this, we first subract the contribution |
| 131 | * of the IP header from the trailer checksum. We then add the |
| 132 | * checksum computed over the pseudo header. |
| 133 | */ |
| 134 | ip_header_csum = (__force __be16)ip_fast_csum(iph: ip6h, ihl: sizeof(*ip6h) / 4); |
| 135 | ip6_payload_csum = csum16_sub(csum: csum_trailer->csum_value, addend: ip_header_csum); |
| 136 | |
| 137 | pseudo_csum = csum_ipv6_magic(saddr: &ip6h->saddr, daddr: &ip6h->daddr, |
| 138 | ntohs(ip6h->payload_len), |
| 139 | proto: ip6h->nexthdr, csum: 0); |
| 140 | |
| 141 | /* It's sufficient to compare the IP payload checksum with the |
| 142 | * negated pseudo checksum to determine whether the packet |
| 143 | * checksum was good. (See further explanation in comments |
| 144 | * in rmnet_map_ipv4_dl_csum_trailer()). |
| 145 | * |
| 146 | * The cast is required to ensure only the low 16 bits are |
| 147 | * examined. |
| 148 | */ |
| 149 | if (ip6_payload_csum != (__sum16)~pseudo_csum) { |
| 150 | priv->stats.csum_validation_failed++; |
| 151 | return -EINVAL; |
| 152 | } |
| 153 | |
| 154 | priv->stats.csum_ok++; |
| 155 | return 0; |
| 156 | } |
| 157 | #else |
| 158 | static int |
| 159 | rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, |
| 160 | struct rmnet_map_dl_csum_trailer *csum_trailer, |
| 161 | struct rmnet_priv *priv) |
| 162 | { |
| 163 | return 0; |
| 164 | } |
| 165 | #endif |
| 166 | |
| 167 | static void rmnet_map_complement_ipv4_txporthdr_csum_field(struct iphdr *ip4h) |
| 168 | { |
| 169 | void *txphdr; |
| 170 | u16 *csum; |
| 171 | |
| 172 | txphdr = (void *)ip4h + ip4h->ihl * 4; |
| 173 | |
| 174 | if (ip4h->protocol == IPPROTO_TCP || ip4h->protocol == IPPROTO_UDP) { |
| 175 | csum = (u16 *)rmnet_map_get_csum_field(protocol: ip4h->protocol, txporthdr: txphdr); |
| 176 | *csum = ~(*csum); |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | static void |
| 181 | (struct iphdr *iphdr, |
| 182 | struct rmnet_map_ul_csum_header *, |
| 183 | struct sk_buff *skb) |
| 184 | { |
| 185 | u16 val; |
| 186 | |
| 187 | val = MAP_CSUM_UL_ENABLED_FLAG; |
| 188 | if (iphdr->protocol == IPPROTO_UDP) |
| 189 | val |= MAP_CSUM_UL_UDP_FLAG; |
| 190 | val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK; |
| 191 | |
| 192 | ul_header->csum_start_offset = htons(skb_network_header_len(skb)); |
| 193 | ul_header->csum_info = htons(val); |
| 194 | |
| 195 | skb->ip_summed = CHECKSUM_NONE; |
| 196 | |
| 197 | rmnet_map_complement_ipv4_txporthdr_csum_field(ip4h: iphdr); |
| 198 | } |
| 199 | |
| 200 | #if IS_ENABLED(CONFIG_IPV6) |
| 201 | static void |
| 202 | rmnet_map_complement_ipv6_txporthdr_csum_field(struct ipv6hdr *ip6h) |
| 203 | { |
| 204 | void *txphdr; |
| 205 | u16 *csum; |
| 206 | |
| 207 | txphdr = ip6h + 1; |
| 208 | |
| 209 | if (ip6h->nexthdr == IPPROTO_TCP || ip6h->nexthdr == IPPROTO_UDP) { |
| 210 | csum = (u16 *)rmnet_map_get_csum_field(protocol: ip6h->nexthdr, txporthdr: txphdr); |
| 211 | *csum = ~(*csum); |
| 212 | } |
| 213 | } |
| 214 | |
| 215 | static void |
| 216 | (struct ipv6hdr *ipv6hdr, |
| 217 | struct rmnet_map_ul_csum_header *, |
| 218 | struct sk_buff *skb) |
| 219 | { |
| 220 | u16 val; |
| 221 | |
| 222 | val = MAP_CSUM_UL_ENABLED_FLAG; |
| 223 | if (ipv6hdr->nexthdr == IPPROTO_UDP) |
| 224 | val |= MAP_CSUM_UL_UDP_FLAG; |
| 225 | val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK; |
| 226 | |
| 227 | ul_header->csum_start_offset = htons(skb_network_header_len(skb)); |
| 228 | ul_header->csum_info = htons(val); |
| 229 | |
| 230 | skb->ip_summed = CHECKSUM_NONE; |
| 231 | |
| 232 | rmnet_map_complement_ipv6_txporthdr_csum_field(ip6h: ipv6hdr); |
| 233 | } |
| 234 | #else |
| 235 | static void |
| 236 | rmnet_map_ipv6_ul_csum_header(void *ip6hdr, |
| 237 | struct rmnet_map_ul_csum_header *ul_header, |
| 238 | struct sk_buff *skb) |
| 239 | { |
| 240 | } |
| 241 | #endif |
| 242 | |
| 243 | static void rmnet_map_v5_checksum_uplink_packet(struct sk_buff *skb, |
| 244 | struct rmnet_port *port, |
| 245 | struct net_device *orig_dev) |
| 246 | { |
| 247 | struct rmnet_priv *priv = netdev_priv(dev: orig_dev); |
| 248 | struct rmnet_map_v5_csum_header *; |
| 249 | |
| 250 | ul_header = skb_push(skb, len: sizeof(*ul_header)); |
| 251 | memset(ul_header, 0, sizeof(*ul_header)); |
| 252 | ul_header->header_info = u8_encode_bits(RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD, |
| 253 | MAPV5_HDRINFO_HDR_TYPE_FMASK); |
| 254 | |
| 255 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
| 256 | void *iph = ip_hdr(skb); |
| 257 | __sum16 *check; |
| 258 | void *trans; |
| 259 | u8 proto; |
| 260 | |
| 261 | if (skb->protocol == htons(ETH_P_IP)) { |
| 262 | u16 ip_len = ((struct iphdr *)iph)->ihl * 4; |
| 263 | |
| 264 | proto = ((struct iphdr *)iph)->protocol; |
| 265 | trans = iph + ip_len; |
| 266 | } else if (IS_ENABLED(CONFIG_IPV6) && |
| 267 | skb->protocol == htons(ETH_P_IPV6)) { |
| 268 | u16 ip_len = sizeof(struct ipv6hdr); |
| 269 | |
| 270 | proto = ((struct ipv6hdr *)iph)->nexthdr; |
| 271 | trans = iph + ip_len; |
| 272 | } else { |
| 273 | priv->stats.csum_err_invalid_ip_version++; |
| 274 | goto sw_csum; |
| 275 | } |
| 276 | |
| 277 | check = rmnet_map_get_csum_field(protocol: proto, txporthdr: trans); |
| 278 | if (check) { |
| 279 | skb->ip_summed = CHECKSUM_NONE; |
| 280 | /* Ask for checksum offloading */ |
| 281 | ul_header->csum_info |= MAPV5_CSUMINFO_VALID_FLAG; |
| 282 | priv->stats.csum_hw++; |
| 283 | return; |
| 284 | } |
| 285 | } |
| 286 | |
| 287 | sw_csum: |
| 288 | priv->stats.csum_sw++; |
| 289 | } |
| 290 | |
| 291 | /* Adds MAP header to front of skb->data |
| 292 | * Padding is calculated and set appropriately in MAP header. Mux ID is |
| 293 | * initialized to 0. |
| 294 | */ |
| 295 | struct rmnet_map_header *(struct sk_buff *skb, |
| 296 | int hdrlen, |
| 297 | struct rmnet_port *port, |
| 298 | int pad) |
| 299 | { |
| 300 | struct rmnet_map_header *; |
| 301 | u32 padding, map_datalen; |
| 302 | |
| 303 | map_datalen = skb->len - hdrlen; |
| 304 | map_header = (struct rmnet_map_header *) |
| 305 | skb_push(skb, len: sizeof(struct rmnet_map_header)); |
| 306 | memset(map_header, 0, sizeof(struct rmnet_map_header)); |
| 307 | |
| 308 | /* Set next_hdr bit for csum offload packets */ |
| 309 | if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5) |
| 310 | map_header->flags |= MAP_NEXT_HEADER_FLAG; |
| 311 | |
| 312 | if (pad == RMNET_MAP_NO_PAD_BYTES) { |
| 313 | map_header->pkt_len = htons(map_datalen); |
| 314 | return map_header; |
| 315 | } |
| 316 | |
| 317 | BUILD_BUG_ON(MAP_PAD_LEN_MASK < 3); |
| 318 | padding = ALIGN(map_datalen, 4) - map_datalen; |
| 319 | |
| 320 | if (padding == 0) |
| 321 | goto done; |
| 322 | |
| 323 | if (skb_tailroom(skb) < padding) |
| 324 | return NULL; |
| 325 | |
| 326 | skb_put_zero(skb, len: padding); |
| 327 | |
| 328 | done: |
| 329 | map_header->pkt_len = htons(map_datalen + padding); |
| 330 | /* This is a data packet, so the CMD bit is 0 */ |
| 331 | map_header->flags = padding & MAP_PAD_LEN_MASK; |
| 332 | |
| 333 | return map_header; |
| 334 | } |
| 335 | |
| 336 | /* Deaggregates a single packet |
| 337 | * A whole new buffer is allocated for each portion of an aggregated frame. |
| 338 | * Caller should keep calling deaggregate() on the source skb until 0 is |
| 339 | * returned, indicating that there are no more packets to deaggregate. Caller |
| 340 | * is responsible for freeing the original skb. |
| 341 | */ |
| 342 | struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb, |
| 343 | struct rmnet_port *port) |
| 344 | { |
| 345 | struct rmnet_map_v5_csum_header *next_hdr = NULL; |
| 346 | struct rmnet_map_header *maph; |
| 347 | void *data = skb->data; |
| 348 | struct sk_buff *skbn; |
| 349 | u8 nexthdr_type; |
| 350 | u32 packet_len; |
| 351 | |
| 352 | if (skb->len == 0) |
| 353 | return NULL; |
| 354 | |
| 355 | maph = (struct rmnet_map_header *)skb->data; |
| 356 | packet_len = ntohs(maph->pkt_len) + sizeof(*maph); |
| 357 | |
| 358 | if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4) { |
| 359 | packet_len += sizeof(struct rmnet_map_dl_csum_trailer); |
| 360 | } else if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) { |
| 361 | if (!(maph->flags & MAP_CMD_FLAG)) { |
| 362 | packet_len += sizeof(*next_hdr); |
| 363 | if (maph->flags & MAP_NEXT_HEADER_FLAG) |
| 364 | next_hdr = data + sizeof(*maph); |
| 365 | else |
| 366 | /* Mapv5 data pkt without csum hdr is invalid */ |
| 367 | return NULL; |
| 368 | } |
| 369 | } |
| 370 | |
| 371 | if (((int)skb->len - (int)packet_len) < 0) |
| 372 | return NULL; |
| 373 | |
| 374 | /* Some hardware can send us empty frames. Catch them */ |
| 375 | if (!maph->pkt_len) |
| 376 | return NULL; |
| 377 | |
| 378 | if (next_hdr) { |
| 379 | nexthdr_type = u8_get_bits(v: next_hdr->header_info, |
| 380 | MAPV5_HDRINFO_HDR_TYPE_FMASK); |
| 381 | if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) |
| 382 | return NULL; |
| 383 | } |
| 384 | |
| 385 | skbn = alloc_skb(size: packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC); |
| 386 | if (!skbn) |
| 387 | return NULL; |
| 388 | |
| 389 | skb_reserve(skb: skbn, RMNET_MAP_DEAGGR_HEADROOM); |
| 390 | skb_put(skb: skbn, len: packet_len); |
| 391 | memcpy(skbn->data, skb->data, packet_len); |
| 392 | skb_pull(skb, len: packet_len); |
| 393 | |
| 394 | return skbn; |
| 395 | } |
| 396 | |
| 397 | /* Validates packet checksums. Function takes a pointer to |
| 398 | * the beginning of a buffer which contains the IP payload + |
| 399 | * padding + checksum trailer. |
| 400 | * Only IPv4 and IPv6 are supported along with TCP & UDP. |
| 401 | * Fragmented or tunneled packets are not supported. |
| 402 | */ |
| 403 | int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len) |
| 404 | { |
| 405 | struct rmnet_priv *priv = netdev_priv(dev: skb->dev); |
| 406 | struct rmnet_map_dl_csum_trailer *csum_trailer; |
| 407 | |
| 408 | if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) { |
| 409 | priv->stats.csum_sw++; |
| 410 | return -EOPNOTSUPP; |
| 411 | } |
| 412 | |
| 413 | csum_trailer = (struct rmnet_map_dl_csum_trailer *)(skb->data + len); |
| 414 | |
| 415 | if (!(csum_trailer->flags & MAP_CSUM_DL_VALID_FLAG)) { |
| 416 | priv->stats.csum_valid_unset++; |
| 417 | return -EINVAL; |
| 418 | } |
| 419 | |
| 420 | if (skb->protocol == htons(ETH_P_IP)) |
| 421 | return rmnet_map_ipv4_dl_csum_trailer(skb, csum_trailer, priv); |
| 422 | |
| 423 | if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) |
| 424 | return rmnet_map_ipv6_dl_csum_trailer(skb, csum_trailer, priv); |
| 425 | |
| 426 | priv->stats.csum_err_invalid_ip_version++; |
| 427 | |
| 428 | return -EPROTONOSUPPORT; |
| 429 | } |
| 430 | |
| 431 | static void rmnet_map_v4_checksum_uplink_packet(struct sk_buff *skb, |
| 432 | struct net_device *orig_dev) |
| 433 | { |
| 434 | struct rmnet_priv *priv = netdev_priv(dev: orig_dev); |
| 435 | struct rmnet_map_ul_csum_header *; |
| 436 | void *iphdr; |
| 437 | |
| 438 | ul_header = (struct rmnet_map_ul_csum_header *) |
| 439 | skb_push(skb, len: sizeof(struct rmnet_map_ul_csum_header)); |
| 440 | |
| 441 | if (unlikely(!(orig_dev->features & |
| 442 | (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)))) |
| 443 | goto sw_csum; |
| 444 | |
| 445 | if (skb->ip_summed != CHECKSUM_PARTIAL) |
| 446 | goto sw_csum; |
| 447 | |
| 448 | iphdr = (char *)ul_header + |
| 449 | sizeof(struct rmnet_map_ul_csum_header); |
| 450 | |
| 451 | if (skb->protocol == htons(ETH_P_IP)) { |
| 452 | rmnet_map_ipv4_ul_csum_header(iphdr, ul_header, skb); |
| 453 | priv->stats.csum_hw++; |
| 454 | return; |
| 455 | } |
| 456 | |
| 457 | if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) { |
| 458 | rmnet_map_ipv6_ul_csum_header(ipv6hdr: iphdr, ul_header, skb); |
| 459 | priv->stats.csum_hw++; |
| 460 | return; |
| 461 | } |
| 462 | |
| 463 | priv->stats.csum_err_invalid_ip_version++; |
| 464 | |
| 465 | sw_csum: |
| 466 | memset(ul_header, 0, sizeof(*ul_header)); |
| 467 | |
| 468 | priv->stats.csum_sw++; |
| 469 | } |
| 470 | |
| 471 | /* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP |
| 472 | * packets that are supported for UL checksum offload. |
| 473 | */ |
| 474 | void rmnet_map_checksum_uplink_packet(struct sk_buff *skb, |
| 475 | struct rmnet_port *port, |
| 476 | struct net_device *orig_dev, |
| 477 | int csum_type) |
| 478 | { |
| 479 | switch (csum_type) { |
| 480 | case RMNET_FLAGS_EGRESS_MAP_CKSUMV4: |
| 481 | rmnet_map_v4_checksum_uplink_packet(skb, orig_dev); |
| 482 | break; |
| 483 | case RMNET_FLAGS_EGRESS_MAP_CKSUMV5: |
| 484 | rmnet_map_v5_checksum_uplink_packet(skb, port, orig_dev); |
| 485 | break; |
| 486 | default: |
| 487 | break; |
| 488 | } |
| 489 | } |
| 490 | |
| 491 | /* Process a MAPv5 packet header */ |
| 492 | int rmnet_map_process_next_hdr_packet(struct sk_buff *skb, |
| 493 | u16 len) |
| 494 | { |
| 495 | struct rmnet_priv *priv = netdev_priv(dev: skb->dev); |
| 496 | struct rmnet_map_v5_csum_header *next_hdr; |
| 497 | u8 nexthdr_type; |
| 498 | |
| 499 | next_hdr = (struct rmnet_map_v5_csum_header *)(skb->data + |
| 500 | sizeof(struct rmnet_map_header)); |
| 501 | |
| 502 | nexthdr_type = u8_get_bits(v: next_hdr->header_info, |
| 503 | MAPV5_HDRINFO_HDR_TYPE_FMASK); |
| 504 | |
| 505 | if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) |
| 506 | return -EINVAL; |
| 507 | |
| 508 | if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) { |
| 509 | priv->stats.csum_sw++; |
| 510 | } else if (next_hdr->csum_info & MAPV5_CSUMINFO_VALID_FLAG) { |
| 511 | priv->stats.csum_ok++; |
| 512 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 513 | } else { |
| 514 | priv->stats.csum_valid_unset++; |
| 515 | } |
| 516 | |
| 517 | /* Pull csum v5 header */ |
| 518 | skb_pull(skb, len: sizeof(*next_hdr)); |
| 519 | |
| 520 | return 0; |
| 521 | } |
| 522 | |
| 523 | #define RMNET_AGG_BYPASS_TIME_NSEC 10000000L |
| 524 | |
| 525 | static void reset_aggr_params(struct rmnet_port *port) |
| 526 | { |
| 527 | port->skbagg_head = NULL; |
| 528 | port->agg_count = 0; |
| 529 | port->agg_state = 0; |
| 530 | memset(&port->agg_time, 0, sizeof(struct timespec64)); |
| 531 | } |
| 532 | |
| 533 | static void rmnet_send_skb(struct rmnet_port *port, struct sk_buff *skb) |
| 534 | { |
| 535 | if (skb_needs_linearize(skb, features: port->dev->features)) { |
| 536 | if (unlikely(__skb_linearize(skb))) { |
| 537 | struct rmnet_priv *priv; |
| 538 | |
| 539 | priv = netdev_priv(dev: port->rmnet_dev); |
| 540 | this_cpu_inc(priv->pcpu_stats->stats.tx_drops); |
| 541 | dev_kfree_skb_any(skb); |
| 542 | return; |
| 543 | } |
| 544 | } |
| 545 | |
| 546 | dev_queue_xmit(skb); |
| 547 | } |
| 548 | |
| 549 | static void rmnet_map_flush_tx_packet_work(struct work_struct *work) |
| 550 | { |
| 551 | struct sk_buff *skb = NULL; |
| 552 | struct rmnet_port *port; |
| 553 | |
| 554 | port = container_of(work, struct rmnet_port, agg_wq); |
| 555 | |
| 556 | spin_lock_bh(lock: &port->agg_lock); |
| 557 | if (likely(port->agg_state == -EINPROGRESS)) { |
| 558 | /* Buffer may have already been shipped out */ |
| 559 | if (likely(port->skbagg_head)) { |
| 560 | skb = port->skbagg_head; |
| 561 | reset_aggr_params(port); |
| 562 | } |
| 563 | port->agg_state = 0; |
| 564 | } |
| 565 | |
| 566 | spin_unlock_bh(lock: &port->agg_lock); |
| 567 | if (skb) |
| 568 | rmnet_send_skb(port, skb); |
| 569 | } |
| 570 | |
| 571 | static enum hrtimer_restart rmnet_map_flush_tx_packet_queue(struct hrtimer *t) |
| 572 | { |
| 573 | struct rmnet_port *port; |
| 574 | |
| 575 | port = container_of(t, struct rmnet_port, hrtimer); |
| 576 | |
| 577 | schedule_work(work: &port->agg_wq); |
| 578 | |
| 579 | return HRTIMER_NORESTART; |
| 580 | } |
| 581 | |
| 582 | unsigned int rmnet_map_tx_aggregate(struct sk_buff *skb, struct rmnet_port *port, |
| 583 | struct net_device *orig_dev) |
| 584 | { |
| 585 | struct timespec64 diff, last; |
| 586 | unsigned int len = skb->len; |
| 587 | struct sk_buff *agg_skb; |
| 588 | int size; |
| 589 | |
| 590 | spin_lock_bh(lock: &port->agg_lock); |
| 591 | memcpy(&last, &port->agg_last, sizeof(struct timespec64)); |
| 592 | ktime_get_real_ts64(tv: &port->agg_last); |
| 593 | |
| 594 | if (!port->skbagg_head) { |
| 595 | /* Check to see if we should agg first. If the traffic is very |
| 596 | * sparse, don't aggregate. |
| 597 | */ |
| 598 | new_packet: |
| 599 | diff = timespec64_sub(lhs: port->agg_last, rhs: last); |
| 600 | size = port->egress_agg_params.bytes - skb->len; |
| 601 | |
| 602 | if (size < 0) { |
| 603 | /* dropped */ |
| 604 | spin_unlock_bh(lock: &port->agg_lock); |
| 605 | return 0; |
| 606 | } |
| 607 | |
| 608 | if (diff.tv_sec > 0 || diff.tv_nsec > RMNET_AGG_BYPASS_TIME_NSEC || |
| 609 | size == 0) |
| 610 | goto no_aggr; |
| 611 | |
| 612 | port->skbagg_head = skb_copy_expand(skb, newheadroom: 0, newtailroom: size, GFP_ATOMIC); |
| 613 | if (!port->skbagg_head) |
| 614 | goto no_aggr; |
| 615 | |
| 616 | dev_kfree_skb_any(skb); |
| 617 | port->skbagg_head->protocol = htons(ETH_P_MAP); |
| 618 | port->agg_count = 1; |
| 619 | ktime_get_real_ts64(tv: &port->agg_time); |
| 620 | skb_frag_list_init(skb: port->skbagg_head); |
| 621 | goto schedule; |
| 622 | } |
| 623 | diff = timespec64_sub(lhs: port->agg_last, rhs: port->agg_time); |
| 624 | size = port->egress_agg_params.bytes - port->skbagg_head->len; |
| 625 | |
| 626 | if (skb->len > size) { |
| 627 | agg_skb = port->skbagg_head; |
| 628 | reset_aggr_params(port); |
| 629 | spin_unlock_bh(lock: &port->agg_lock); |
| 630 | hrtimer_cancel(timer: &port->hrtimer); |
| 631 | rmnet_send_skb(port, skb: agg_skb); |
| 632 | spin_lock_bh(lock: &port->agg_lock); |
| 633 | goto new_packet; |
| 634 | } |
| 635 | |
| 636 | if (skb_has_frag_list(skb: port->skbagg_head)) |
| 637 | port->skbagg_tail->next = skb; |
| 638 | else |
| 639 | skb_shinfo(port->skbagg_head)->frag_list = skb; |
| 640 | |
| 641 | port->skbagg_head->len += skb->len; |
| 642 | port->skbagg_head->data_len += skb->len; |
| 643 | port->skbagg_head->truesize += skb->truesize; |
| 644 | port->skbagg_tail = skb; |
| 645 | port->agg_count++; |
| 646 | |
| 647 | if (diff.tv_sec > 0 || diff.tv_nsec > port->egress_agg_params.time_nsec || |
| 648 | port->agg_count >= port->egress_agg_params.count || |
| 649 | port->skbagg_head->len == port->egress_agg_params.bytes) { |
| 650 | agg_skb = port->skbagg_head; |
| 651 | reset_aggr_params(port); |
| 652 | spin_unlock_bh(lock: &port->agg_lock); |
| 653 | hrtimer_cancel(timer: &port->hrtimer); |
| 654 | rmnet_send_skb(port, skb: agg_skb); |
| 655 | return len; |
| 656 | } |
| 657 | |
| 658 | schedule: |
| 659 | if (!hrtimer_active(timer: &port->hrtimer) && port->agg_state != -EINPROGRESS) { |
| 660 | port->agg_state = -EINPROGRESS; |
| 661 | hrtimer_start(timer: &port->hrtimer, |
| 662 | tim: ns_to_ktime(ns: port->egress_agg_params.time_nsec), |
| 663 | mode: HRTIMER_MODE_REL); |
| 664 | } |
| 665 | spin_unlock_bh(lock: &port->agg_lock); |
| 666 | |
| 667 | return len; |
| 668 | |
| 669 | no_aggr: |
| 670 | spin_unlock_bh(lock: &port->agg_lock); |
| 671 | skb->protocol = htons(ETH_P_MAP); |
| 672 | dev_queue_xmit(skb); |
| 673 | |
| 674 | return len; |
| 675 | } |
| 676 | |
| 677 | void rmnet_map_update_ul_agg_config(struct rmnet_port *port, u32 size, |
| 678 | u32 count, u32 time) |
| 679 | { |
| 680 | spin_lock_bh(lock: &port->agg_lock); |
| 681 | port->egress_agg_params.bytes = size; |
| 682 | WRITE_ONCE(port->egress_agg_params.count, count); |
| 683 | port->egress_agg_params.time_nsec = time * NSEC_PER_USEC; |
| 684 | spin_unlock_bh(lock: &port->agg_lock); |
| 685 | } |
| 686 | |
| 687 | void rmnet_map_tx_aggregate_init(struct rmnet_port *port) |
| 688 | { |
| 689 | hrtimer_setup(timer: &port->hrtimer, function: rmnet_map_flush_tx_packet_queue, CLOCK_MONOTONIC, |
| 690 | mode: HRTIMER_MODE_REL); |
| 691 | spin_lock_init(&port->agg_lock); |
| 692 | rmnet_map_update_ul_agg_config(port, size: 4096, count: 1, time: 800); |
| 693 | INIT_WORK(&port->agg_wq, rmnet_map_flush_tx_packet_work); |
| 694 | } |
| 695 | |
| 696 | void rmnet_map_tx_aggregate_exit(struct rmnet_port *port) |
| 697 | { |
| 698 | hrtimer_cancel(timer: &port->hrtimer); |
| 699 | cancel_work_sync(work: &port->agg_wq); |
| 700 | |
| 701 | spin_lock_bh(lock: &port->agg_lock); |
| 702 | if (port->agg_state == -EINPROGRESS) { |
| 703 | if (port->skbagg_head) { |
| 704 | dev_kfree_skb_any(skb: port->skbagg_head); |
| 705 | reset_aggr_params(port); |
| 706 | } |
| 707 | |
| 708 | port->agg_state = 0; |
| 709 | } |
| 710 | spin_unlock_bh(lock: &port->agg_lock); |
| 711 | } |
| 712 | |