1/* 2 * Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``S IS''AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27/* 28 * $FreeBSD: stable/11/sys/net/netmap.h 343866 2019-02-07 10:44:53Z vmaffione $ 29 * 30 * Definitions of constants and the structures used by the netmap 31 * framework, for the part visible to both kernel and userspace. 32 * Detailed info on netmap is available with "man netmap" or at 33 * 34 * http://info.iet.unipi.it/~luigi/netmap/ 35 * 36 * This API is also used to communicate with the VALE software switch 37 */ 38 39#ifndef _NET_NETMAP_H_ 40#define _NET_NETMAP_H_ 41 42#define NETMAP_API 13 /* current API version */ 43 44#define NETMAP_MIN_API 13 /* min and max versions accepted */ 45#define NETMAP_MAX_API 15 46/* 47 * Some fields should be cache-aligned to reduce contention. 48 * The alignment is architecture and OS dependent, but rather than 49 * digging into OS headers to find the exact value we use an estimate 50 * that should cover most architectures. 51 */ 52#define NM_CACHE_ALIGN 128 53 54/* 55 * --- Netmap data structures --- 56 * 57 * The userspace data structures used by netmap are shown below. 58 * They are allocated by the kernel and mmap()ed by userspace threads. 59 * Pointers are implemented as memory offsets or indexes, 60 * so that they can be easily dereferenced in kernel and userspace. 61 62 KERNEL (opaque, obviously) 63 64 ==================================================================== 65 | 66 USERSPACE | struct netmap_ring 67 +---->+---------------+ 68 / | head,cur,tail | 69 struct netmap_if (nifp, 1 per fd) / | buf_ofs | 70 +---------------+ / | other fields | 71 | ni_tx_rings | / +===============+ 72 | ni_rx_rings | / | buf_idx, len | slot[0] 73 | | / | flags, ptr | 74 | | / +---------------+ 75 +===============+ / | buf_idx, len | slot[1] 76 | txring_ofs[0] | (rel.to nifp)--' | flags, ptr | 77 | txring_ofs[1] | +---------------+ 78 (tx+1 entries) (num_slots entries) 79 | txring_ofs[t] | | buf_idx, len | slot[n-1] 80 +---------------+ | flags, ptr | 81 | rxring_ofs[0] | +---------------+ 82 | rxring_ofs[1] | 83 (rx+1 entries) 84 | rxring_ofs[r] | 85 +---------------+ 86 87 * For each "interface" (NIC, host stack, PIPE, VALE switch port) bound to 88 * a file descriptor, the mmap()ed region contains a (logically readonly) 89 * struct netmap_if pointing to struct netmap_ring's. 90 * 91 * There is one netmap_ring per physical NIC ring, plus one tx/rx ring 92 * pair attached to the host stack (this pair is unused for non-NIC ports). 93 * 94 * All physical/host stack ports share the same memory region, 95 * so that zero-copy can be implemented between them. 96 * VALE switch ports instead have separate memory regions. 97 * 98 * The netmap_ring is the userspace-visible replica of the NIC ring. 99 * Each slot has the index of a buffer (MTU-sized and residing in the 100 * mmapped region), its length and some flags. An extra 64-bit pointer 101 * is provided for user-supplied buffers in the tx path. 102 * 103 * In user space, the buffer address is computed as 104 * (char *)ring + buf_ofs + index * NETMAP_BUF_SIZE 105 * 106 * Added in NETMAP_API 11: 107 * 108 * + NIOCREGIF can request the allocation of extra spare buffers from 109 * the same memory pool. The desired number of buffers must be in 110 * nr_arg3. The ioctl may return fewer buffers, depending on memory 111 * availability. nr_arg3 will return the actual value, and, once 112 * mapped, nifp->ni_bufs_head will be the index of the first buffer. 113 * 114 * The buffers are linked to each other using the first uint32_t 115 * as the index. On close, ni_bufs_head must point to the list of 116 * buffers to be released. 117 * 118 * + NIOCREGIF can request space for extra rings (and buffers) 119 * allocated in the same memory space. The number of extra rings 120 * is in nr_arg1, and is advisory. This is a no-op on NICs where 121 * the size of the memory space is fixed. 122 * 123 * + NIOCREGIF can attach to PIPE rings sharing the same memory 124 * space with a parent device. The ifname indicates the parent device, 125 * which must already exist. Flags in nr_flags indicate if we want to 126 * bind the master or slave side, the index (from nr_ringid) 127 * is just a cookie and does not need to be sequential. 128 * 129 * + NIOCREGIF can also attach to 'monitor' rings that replicate 130 * the content of specific rings, also from the same memory space. 131 * 132 * Extra flags in nr_flags support the above functions. 133 * Application libraries may use the following naming scheme: 134 * netmap:foo all NIC ring pairs 135 * netmap:foo^ only host ring pair 136 * netmap:foo+ all NIC ring + host ring pairs 137 * netmap:foo-k the k-th NIC ring pair 138 * netmap:foo{k PIPE ring pair k, master side 139 * netmap:foo}k PIPE ring pair k, slave side 140 * 141 * Some notes about host rings: 142 * 143 * + The RX host ring is used to store those packets that the host network 144 * stack is trying to transmit through a NIC queue, but only if that queue 145 * is currently in netmap mode. Netmap will not intercept host stack mbufs 146 * designated to NIC queues that are not in netmap mode. As a consequence, 147 * registering a netmap port with netmap:foo^ is not enough to intercept 148 * mbufs in the RX host ring; the netmap port should be registered with 149 * netmap:foo*, or another registration should be done to open at least a 150 * NIC TX queue in netmap mode. 151 * 152 * + Netmap is not currently able to deal with intercepted trasmit mbufs which 153 * require offloadings like TSO, UFO, checksumming offloadings, etc. It is 154 * responsibility of the user to disable those offloadings (e.g. using 155 * ifconfig on FreeBSD or ethtool -K on Linux) for an interface that is being 156 * used in netmap mode. If the offloadings are not disabled, GSO and/or 157 * unchecksummed packets may be dropped immediately or end up in the host RX 158 * ring, and will be dropped as soon as the packet reaches another netmap 159 * adapter. 160 */ 161 162/* 163 * struct netmap_slot is a buffer descriptor 164 */ 165struct netmap_slot { 166 uint32_t buf_idx; /* buffer index */ 167 uint16_t len; /* length for this slot */ 168 uint16_t flags; /* buf changed, etc. */ 169 uint64_t ptr; /* pointer for indirect buffers */ 170}; 171 172/* 173 * The following flags control how the slot is used 174 */ 175 176#define NS_BUF_CHANGED 0x0001 /* buf_idx changed */ 177 /* 178 * must be set whenever buf_idx is changed (as it might be 179 * necessary to recompute the physical address and mapping) 180 * 181 * It is also set by the kernel whenever the buf_idx is 182 * changed internally (e.g., by pipes). Applications may 183 * use this information to know when they can reuse the 184 * contents of previously prepared buffers. 185 */ 186 187#define NS_REPORT 0x0002 /* ask the hardware to report results */ 188 /* 189 * Request notification when slot is used by the hardware. 190 * Normally transmit completions are handled lazily and 191 * may be unreported. This flag lets us know when a slot 192 * has been sent (e.g. to terminate the sender). 193 */ 194 195#define NS_FORWARD 0x0004 /* pass packet 'forward' */ 196 /* 197 * (Only for physical ports, rx rings with NR_FORWARD set). 198 * Slot released to the kernel (i.e. before ring->head) with 199 * this flag set are passed to the peer ring (host/NIC), 200 * thus restoring the host-NIC connection for these slots. 201 * This supports efficient traffic monitoring or firewalling. 202 */ 203 204#define NS_NO_LEARN 0x0008 /* disable bridge learning */ 205 /* 206 * On a VALE switch, do not 'learn' the source port for 207 * this buffer. 208 */ 209 210#define NS_INDIRECT 0x0010 /* userspace buffer */ 211 /* 212 * (VALE tx rings only) data is in a userspace buffer, 213 * whose address is in the 'ptr' field in the slot. 214 */ 215 216#define NS_MOREFRAG 0x0020 /* packet has more fragments */ 217 /* 218 * (VALE ports, ptnetmap ports and some NIC ports, e.g. 219 * ixgbe and i40e on Linux) 220 * Set on all but the last slot of a multi-segment packet. 221 * The 'len' field refers to the individual fragment. 222 */ 223 224#define NS_PORT_SHIFT 8 225#define NS_PORT_MASK (0xff << NS_PORT_SHIFT) 226 /* 227 * The high 8 bits of the flag, if not zero, indicate the 228 * destination port for the VALE switch, overriding 229 * the lookup table. 230 */ 231 232#define NS_RFRAGS(_slot) ( ((_slot)->flags >> 8) & 0xff) 233 /* 234 * (VALE rx rings only) the high 8 bits 235 * are the number of fragments. 236 */ 237 238#define NETMAP_MAX_FRAGS 64 /* max number of fragments */ 239 240 241/* 242 * struct netmap_ring 243 * 244 * Netmap representation of a TX or RX ring (also known as "queue"). 245 * This is a queue implemented as a fixed-size circular array. 246 * At the software level the important fields are: head, cur, tail. 247 * 248 * In TX rings: 249 * 250 * head first slot available for transmission. 251 * cur wakeup point. select() and poll() will unblock 252 * when 'tail' moves past 'cur' 253 * tail (readonly) first slot reserved to the kernel 254 * 255 * [head .. tail-1] can be used for new packets to send; 256 * 'head' and 'cur' must be incremented as slots are filled 257 * with new packets to be sent; 258 * 'cur' can be moved further ahead if we need more space 259 * for new transmissions. XXX todo (2014-03-12) 260 * 261 * In RX rings: 262 * 263 * head first valid received packet 264 * cur wakeup point. select() and poll() will unblock 265 * when 'tail' moves past 'cur' 266 * tail (readonly) first slot reserved to the kernel 267 * 268 * [head .. tail-1] contain received packets; 269 * 'head' and 'cur' must be incremented as slots are consumed 270 * and can be returned to the kernel; 271 * 'cur' can be moved further ahead if we want to wait for 272 * new packets without returning the previous ones. 273 * 274 * DATA OWNERSHIP/LOCKING: 275 * The netmap_ring, and all slots and buffers in the range 276 * [head .. tail-1] are owned by the user program; 277 * the kernel only accesses them during a netmap system call 278 * and in the user thread context. 279 * 280 * Other slots and buffers are reserved for use by the kernel 281 */ 282struct netmap_ring { 283 /* 284 * buf_ofs is meant to be used through macros. 285 * It contains the offset of the buffer region from this 286 * descriptor. 287 */ 288 const int64_t buf_ofs; 289 const uint32_t num_slots; /* number of slots in the ring. */ 290 const uint32_t nr_buf_size; 291 const uint16_t ringid; 292 const uint16_t dir; /* 0: tx, 1: rx */ 293 294 uint32_t head; /* (u) first user slot */ 295 uint32_t cur; /* (u) wakeup point */ 296 uint32_t tail; /* (k) first kernel slot */ 297 298 uint32_t flags; 299 300 struct timeval ts; /* (k) time of last *sync() */ 301 302 /* opaque room for a mutex or similar object */ 303#if !defined(_WIN32) || defined(__CYGWIN__) 304 uint8_t __attribute__((__aligned__(NM_CACHE_ALIGN))) sem[128]; 305#else 306 uint8_t __declspec(align(NM_CACHE_ALIGN)) sem[128]; 307#endif 308 309 /* the slots follow. This struct has variable size */ 310 struct netmap_slot slot[0]; /* array of slots. */ 311}; 312 313 314/* 315 * RING FLAGS 316 */ 317#define NR_TIMESTAMP 0x0002 /* set timestamp on *sync() */ 318 /* 319 * updates the 'ts' field on each netmap syscall. This saves 320 * saves a separate gettimeofday(), and is not much worse than 321 * software timestamps generated in the interrupt handler. 322 */ 323 324#define NR_FORWARD 0x0004 /* enable NS_FORWARD for ring */ 325 /* 326 * Enables the NS_FORWARD slot flag for the ring. 327 */ 328 329/* 330 * Helper functions for kernel and userspace 331 */ 332 333/* 334 * Check if space is available in the ring. We use ring->head, which 335 * points to the next netmap slot to be published to netmap. It is 336 * possible that the applications moves ring->cur ahead of ring->tail 337 * (e.g., by setting ring->cur <== ring->tail), if it wants more slots 338 * than the ones currently available, and it wants to be notified when 339 * more arrive. See netmap(4) for more details and examples. 340 */ 341static inline int 342nm_ring_empty(struct netmap_ring *ring) 343{ 344 return (ring->head == ring->tail); 345} 346 347/* 348 * Netmap representation of an interface and its queue(s). 349 * This is initialized by the kernel when binding a file 350 * descriptor to a port, and should be considered as readonly 351 * by user programs. The kernel never uses it. 352 * 353 * There is one netmap_if for each file descriptor on which we want 354 * to select/poll. 355 * select/poll operates on one or all pairs depending on the value of 356 * nmr_queueid passed on the ioctl. 357 */ 358struct netmap_if { 359 char ni_name[IFNAMSIZ]; /* name of the interface. */ 360 const uint32_t ni_version; /* API version, currently unused */ 361 const uint32_t ni_flags; /* properties */ 362#define NI_PRIV_MEM 0x1 /* private memory region */ 363 364 /* 365 * The number of packet rings available in netmap mode. 366 * Physical NICs can have different numbers of tx and rx rings. 367 * Physical NICs also have a 'host' ring pair. 368 * Additionally, clients can request additional ring pairs to 369 * be used for internal communication. 370 */ 371 const uint32_t ni_tx_rings; /* number of HW tx rings */ 372 const uint32_t ni_rx_rings; /* number of HW rx rings */ 373 374 uint32_t ni_bufs_head; /* head index for extra bufs */ 375 uint32_t ni_spare1[5]; 376 /* 377 * The following array contains the offset of each netmap ring 378 * from this structure, in the following order: 379 * NIC tx rings (ni_tx_rings); host tx ring (1); extra tx rings; 380 * NIC rx rings (ni_rx_rings); host tx ring (1); extra rx rings. 381 * 382 * The area is filled up by the kernel on NIOCREGIF, 383 * and then only read by userspace code. 384 */ 385 const ssize_t ring_ofs[0]; 386}; 387 388/* Legacy interface to interact with a netmap control device. 389 * Included for backward compatibility. The user should not include this 390 * file directly. */ 391#include "netmap_legacy.h" 392 393/* 394 * New API to control netmap control devices. New applications should only use 395 * nmreq_xyz structs with the NIOCCTRL ioctl() command. 396 * 397 * NIOCCTRL takes a nmreq_header struct, which contains the required 398 * API version, the name of a netmap port, a command type, and pointers 399 * to request body and options. 400 * 401 * nr_name (in) 402 * The name of the port (em0, valeXXX:YYY, eth0{pn1 etc.) 403 * 404 * nr_version (in/out) 405 * Must match NETMAP_API as used in the kernel, error otherwise. 406 * Always returns the desired value on output. 407 * 408 * nr_reqtype (in) 409 * One of the NETMAP_REQ_* command types below 410 * 411 * nr_body (in) 412 * Pointer to a command-specific struct, described by one 413 * of the struct nmreq_xyz below. 414 * 415 * nr_options (in) 416 * Command specific options, if any. 417 * 418 * A NETMAP_REQ_REGISTER command activates netmap mode on the netmap 419 * port (e.g. physical interface) specified by nmreq_header.nr_name. 420 * The request body (struct nmreq_register) has several arguments to 421 * specify how the port is to be registered. 422 * 423 * nr_tx_slots, nr_tx_slots, nr_tx_rings, nr_rx_rings (in/out) 424 * On input, non-zero values may be used to reconfigure the port 425 * according to the requested values, but this is not guaranteed. 426 * On output the actual values in use are reported. 427 * 428 * nr_mode (in) 429 * Indicate what set of rings must be bound to the netmap 430 * device (e.g. all NIC rings, host rings only, NIC and 431 * host rings, ...). Values are in NR_REG_*. 432 * 433 * nr_ringid (in) 434 * If nr_mode == NR_REG_ONE_NIC (only a single couple of TX/RX 435 * rings), indicate which NIC TX and/or RX ring is to be bound 436 * (0..nr_*x_rings-1). 437 * 438 * nr_flags (in) 439 * Indicate special options for how to open the port. 440 * 441 * NR_NO_TX_POLL can be OR-ed to make select()/poll() push 442 * packets on tx rings only if POLLOUT is set. 443 * The default is to push any pending packet. 444 * 445 * NR_DO_RX_POLL can be OR-ed to make select()/poll() release 446 * packets on rx rings also when POLLIN is NOT set. 447 * The default is to touch the rx ring only with POLLIN. 448 * Note that this is the opposite of TX because it 449 * reflects the common usage. 450 * 451 * Other options are NR_MONITOR_TX, NR_MONITOR_RX, NR_ZCOPY_MON, 452 * NR_EXCLUSIVE, NR_RX_RINGS_ONLY, NR_TX_RINGS_ONLY and 453 * NR_ACCEPT_VNET_HDR. 454 * 455 * nr_mem_id (in/out) 456 * The identity of the memory region used. 457 * On input, 0 means the system decides autonomously, 458 * other values may try to select a specific region. 459 * On return the actual value is reported. 460 * Region '1' is the global allocator, normally shared 461 * by all interfaces. Other values are private regions. 462 * If two ports the same region zero-copy is possible. 463 * 464 * nr_extra_bufs (in/out) 465 * Number of extra buffers to be allocated. 466 * 467 * The other NETMAP_REQ_* commands are described below. 468 * 469 */ 470 471/* maximum size of a request, including all options */ 472#define NETMAP_REQ_MAXSIZE 4096 473 474/* Header common to all request options. */ 475struct nmreq_option { 476 /* Pointer ot the next option. */ 477 uint64_t nro_next; 478 /* Option type. */ 479 uint32_t nro_reqtype; 480 /* (out) status of the option: 481 * 0: recognized and processed 482 * !=0: errno value 483 */ 484 uint32_t nro_status; 485 /* Option size, used only for options that can have variable size 486 * (e.g. because they contain arrays). For fixed-size options this 487 * field should be set to zero. */ 488 uint64_t nro_size; 489}; 490 491/* Header common to all requests. Do not reorder these fields, as we need 492 * the second one (nr_reqtype) to know how much to copy from/to userspace. */ 493struct nmreq_header { 494 uint16_t nr_version; /* API version */ 495 uint16_t nr_reqtype; /* nmreq type (NETMAP_REQ_*) */ 496 uint32_t nr_reserved; /* must be zero */ 497#define NETMAP_REQ_IFNAMSIZ 64 498 char nr_name[NETMAP_REQ_IFNAMSIZ]; /* port name */ 499 uint64_t nr_options; /* command-specific options */ 500 uint64_t nr_body; /* ptr to nmreq_xyz struct */ 501}; 502 503enum { 504 /* Register a netmap port with the device. */ 505 NETMAP_REQ_REGISTER = 1, 506 /* Get information from a netmap port. */ 507 NETMAP_REQ_PORT_INFO_GET, 508 /* Attach a netmap port to a VALE switch. */ 509 NETMAP_REQ_VALE_ATTACH, 510 /* Detach a netmap port from a VALE switch. */ 511 NETMAP_REQ_VALE_DETACH, 512 /* List the ports attached to a VALE switch. */ 513 NETMAP_REQ_VALE_LIST, 514 /* Set the port header length (was virtio-net header length). */ 515 NETMAP_REQ_PORT_HDR_SET, 516 /* Get the port header length (was virtio-net header length). */ 517 NETMAP_REQ_PORT_HDR_GET, 518 /* Create a new persistent VALE port. */ 519 NETMAP_REQ_VALE_NEWIF, 520 /* Delete a persistent VALE port. */ 521 NETMAP_REQ_VALE_DELIF, 522 /* Enable polling kernel thread(s) on an attached VALE port. */ 523 NETMAP_REQ_VALE_POLLING_ENABLE, 524 /* Disable polling kernel thread(s) on an attached VALE port. */ 525 NETMAP_REQ_VALE_POLLING_DISABLE, 526 /* Get info about the pools of a memory allocator. */ 527 NETMAP_REQ_POOLS_INFO_GET, 528 /* Start an in-kernel loop that syncs the rings periodically or 529 * on notifications. The loop runs in the context of the ioctl 530 * syscall, and only stops on NETMAP_REQ_SYNC_KLOOP_STOP. */ 531 NETMAP_REQ_SYNC_KLOOP_START, 532 /* Stops the thread executing the in-kernel loop. The thread 533 * returns from the ioctl syscall. */ 534 NETMAP_REQ_SYNC_KLOOP_STOP, 535 /* Enable CSB mode on a registered netmap control device. */ 536 NETMAP_REQ_CSB_ENABLE, 537}; 538 539enum { 540 /* On NETMAP_REQ_REGISTER, ask netmap to use memory allocated 541 * from user-space allocated memory pools (e.g. hugepages). 542 */ 543 NETMAP_REQ_OPT_EXTMEM = 1, 544 545 /* ON NETMAP_REQ_SYNC_KLOOP_START, ask netmap to use eventfd-based 546 * notifications to synchronize the kernel loop with the application. 547 */ 548 NETMAP_REQ_OPT_SYNC_KLOOP_EVENTFDS, 549 550 /* On NETMAP_REQ_REGISTER, ask netmap to work in CSB mode, where 551 * head, cur and tail pointers are not exchanged through the 552 * struct netmap_ring header, but rather using an user-provided 553 * memory area (see struct nm_csb_atok and struct nm_csb_ktoa). 554 */ 555 NETMAP_REQ_OPT_CSB, 556 557 /* An extension to NETMAP_REQ_OPT_SYNC_KLOOP_EVENTFDS, which specifies 558 * if the TX and/or RX rings are synced in the context of the VM exit. 559 * This requires the 'ioeventfd' fields to be valid (cannot be < 0). 560 */ 561 NETMAP_REQ_OPT_SYNC_KLOOP_MODE, 562}; 563 564/* 565 * nr_reqtype: NETMAP_REQ_REGISTER 566 * Bind (register) a netmap port to this control device. 567 */ 568struct nmreq_register { 569 uint64_t nr_offset; /* nifp offset in the shared region */ 570 uint64_t nr_memsize; /* size of the shared region */ 571 uint32_t nr_tx_slots; /* slots in tx rings */ 572 uint32_t nr_rx_slots; /* slots in rx rings */ 573 uint16_t nr_tx_rings; /* number of tx rings */ 574 uint16_t nr_rx_rings; /* number of rx rings */ 575 576 uint16_t nr_mem_id; /* id of the memory allocator */ 577 uint16_t nr_ringid; /* ring(s) we care about */ 578 uint32_t nr_mode; /* specify NR_REG_* modes */ 579 uint32_t nr_extra_bufs; /* number of requested extra buffers */ 580 581 uint64_t nr_flags; /* additional flags (see below) */ 582/* monitors use nr_ringid and nr_mode to select the rings to monitor */ 583#define NR_MONITOR_TX 0x100 584#define NR_MONITOR_RX 0x200 585#define NR_ZCOPY_MON 0x400 586/* request exclusive access to the selected rings */ 587#define NR_EXCLUSIVE 0x800 588/* 0x1000 unused */ 589#define NR_RX_RINGS_ONLY 0x2000 590#define NR_TX_RINGS_ONLY 0x4000 591/* Applications set this flag if they are able to deal with virtio-net headers, 592 * that is send/receive frames that start with a virtio-net header. 593 * If not set, NIOCREGIF will fail with netmap ports that require applications 594 * to use those headers. If the flag is set, the application can use the 595 * NETMAP_VNET_HDR_GET command to figure out the header length. */ 596#define NR_ACCEPT_VNET_HDR 0x8000 597/* The following two have the same meaning of NETMAP_NO_TX_POLL and 598 * NETMAP_DO_RX_POLL. */ 599#define NR_DO_RX_POLL 0x10000 600#define NR_NO_TX_POLL 0x20000 601}; 602 603/* Valid values for nmreq_register.nr_mode (see above). */ 604enum { NR_REG_DEFAULT = 0, /* backward compat, should not be used. */ 605 NR_REG_ALL_NIC = 1, 606 NR_REG_SW = 2, 607 NR_REG_NIC_SW = 3, 608 NR_REG_ONE_NIC = 4, 609 NR_REG_PIPE_MASTER = 5, /* deprecated, use "x{y" port name syntax */ 610 NR_REG_PIPE_SLAVE = 6, /* deprecated, use "x}y" port name syntax */ 611 NR_REG_NULL = 7, 612}; 613 614/* A single ioctl number is shared by all the new API command. 615 * Demultiplexing is done using the hdr.nr_reqtype field. 616 * FreeBSD uses the size value embedded in the _IOWR to determine 617 * how much to copy in/out, so we define the ioctl() command 618 * specifying only nmreq_header, and copyin/copyout the rest. */ 619#define NIOCCTRL _IOWR('i', 151, struct nmreq_header) 620 621/* The ioctl commands to sync TX/RX netmap rings. 622 * NIOCTXSYNC, NIOCRXSYNC synchronize tx or rx queues, 623 * whose identity is set in NIOCREGIF through nr_ringid. 624 * These are non blocking and take no argument. */ 625#define NIOCTXSYNC _IO('i', 148) /* sync tx queues */ 626#define NIOCRXSYNC _IO('i', 149) /* sync rx queues */ 627 628/* 629 * nr_reqtype: NETMAP_REQ_PORT_INFO_GET 630 * Get information about a netmap port, including number of rings. 631 * slots per ring, id of the memory allocator, etc. The netmap 632 * control device used for this operation does not need to be bound 633 * to a netmap port. 634 */ 635struct nmreq_port_info_get { 636 uint64_t nr_memsize; /* size of the shared region */ 637 uint32_t nr_tx_slots; /* slots in tx rings */ 638 uint32_t nr_rx_slots; /* slots in rx rings */ 639 uint16_t nr_tx_rings; /* number of tx rings */ 640 uint16_t nr_rx_rings; /* number of rx rings */ 641 uint16_t nr_mem_id; /* memory allocator id (in/out) */ 642 uint16_t pad1; 643}; 644 645#define NM_BDG_NAME "vale" /* prefix for bridge port name */ 646 647/* 648 * nr_reqtype: NETMAP_REQ_VALE_ATTACH 649 * Attach a netmap port to a VALE switch. Both the name of the netmap 650 * port and the VALE switch are specified through the nr_name argument. 651 * The attach operation could need to register a port, so at least 652 * the same arguments are available. 653 * port_index will contain the index where the port has been attached. 654 */ 655struct nmreq_vale_attach { 656 struct nmreq_register reg; 657 uint32_t port_index; 658 uint32_t pad1; 659}; 660 661/* 662 * nr_reqtype: NETMAP_REQ_VALE_DETACH 663 * Detach a netmap port from a VALE switch. Both the name of the netmap 664 * port and the VALE switch are specified through the nr_name argument. 665 * port_index will contain the index where the port was attached. 666 */ 667struct nmreq_vale_detach { 668 uint32_t port_index; 669 uint32_t pad1; 670}; 671 672/* 673 * nr_reqtype: NETMAP_REQ_VALE_LIST 674 * List the ports of a VALE switch. 675 */ 676struct nmreq_vale_list { 677 /* Name of the VALE port (valeXXX:YYY) or empty. */ 678 uint16_t nr_bridge_idx; 679 uint16_t pad1; 680 uint32_t nr_port_idx; 681}; 682 683/* 684 * nr_reqtype: NETMAP_REQ_PORT_HDR_SET or NETMAP_REQ_PORT_HDR_GET 685 * Set or get the port header length of the port identified by hdr.nr_name. 686 * The control device does not need to be bound to a netmap port. 687 */ 688struct nmreq_port_hdr { 689 uint32_t nr_hdr_len; 690 uint32_t pad1; 691}; 692 693/* 694 * nr_reqtype: NETMAP_REQ_VALE_NEWIF 695 * Create a new persistent VALE port. 696 */ 697struct nmreq_vale_newif { 698 uint32_t nr_tx_slots; /* slots in tx rings */ 699 uint32_t nr_rx_slots; /* slots in rx rings */ 700 uint16_t nr_tx_rings; /* number of tx rings */ 701 uint16_t nr_rx_rings; /* number of rx rings */ 702 uint16_t nr_mem_id; /* id of the memory allocator */ 703 uint16_t pad1; 704}; 705 706/* 707 * nr_reqtype: NETMAP_REQ_VALE_POLLING_ENABLE or NETMAP_REQ_VALE_POLLING_DISABLE 708 * Enable or disable polling kthreads on a VALE port. 709 */ 710struct nmreq_vale_polling { 711 uint32_t nr_mode; 712#define NETMAP_POLLING_MODE_SINGLE_CPU 1 713#define NETMAP_POLLING_MODE_MULTI_CPU 2 714 uint32_t nr_first_cpu_id; 715 uint32_t nr_num_polling_cpus; 716 uint32_t pad1; 717}; 718 719/* 720 * nr_reqtype: NETMAP_REQ_POOLS_INFO_GET 721 * Get info about the pools of the memory allocator of the netmap 722 * port specified by hdr.nr_name and nr_mem_id. The netmap control 723 * device used for this operation does not need to be bound to a netmap 724 * port. 725 */ 726struct nmreq_pools_info { 727 uint64_t nr_memsize; 728 uint16_t nr_mem_id; /* in/out argument */ 729 uint16_t pad1[3]; 730 uint64_t nr_if_pool_offset; 731 uint32_t nr_if_pool_objtotal; 732 uint32_t nr_if_pool_objsize; 733 uint64_t nr_ring_pool_offset; 734 uint32_t nr_ring_pool_objtotal; 735 uint32_t nr_ring_pool_objsize; 736 uint64_t nr_buf_pool_offset; 737 uint32_t nr_buf_pool_objtotal; 738 uint32_t nr_buf_pool_objsize; 739}; 740 741/* 742 * nr_reqtype: NETMAP_REQ_SYNC_KLOOP_START 743 * Start an in-kernel loop that syncs the rings periodically or on 744 * notifications. The loop runs in the context of the ioctl syscall, 745 * and only stops on NETMAP_REQ_SYNC_KLOOP_STOP. 746 * The registered netmap port must be open in CSB mode. 747 */ 748struct nmreq_sync_kloop_start { 749 /* Sleeping is the default synchronization method for the kloop. 750 * The 'sleep_us' field specifies how many microsconds to sleep for 751 * when there is no work to do, before doing another kloop iteration. 752 */ 753 uint32_t sleep_us; 754 uint32_t pad1; 755}; 756 757/* A CSB entry for the application --> kernel direction. */ 758struct nm_csb_atok { 759 uint32_t head; /* AW+ KR+ the head of the appl netmap_ring */ 760 uint32_t cur; /* AW+ KR+ the cur of the appl netmap_ring */ 761 uint32_t appl_need_kick; /* AW+ KR+ kern --> appl notification enable */ 762 uint32_t sync_flags; /* AW+ KR+ the flags of the appl [tx|rx]sync() */ 763 uint32_t pad[12]; /* pad to a 64 bytes cacheline */ 764}; 765 766/* A CSB entry for the application <-- kernel direction. */ 767struct nm_csb_ktoa { 768 uint32_t hwcur; /* AR+ KW+ the hwcur of the kern netmap_kring */ 769 uint32_t hwtail; /* AR+ KW+ the hwtail of the kern netmap_kring */ 770 uint32_t kern_need_kick; /* AR+ KW+ appl-->kern notification enable */ 771 uint32_t pad[13]; 772}; 773 774#ifdef __linux__ 775 776#ifdef __KERNEL__ 777#define nm_stst_barrier smp_wmb 778#define nm_ldld_barrier smp_rmb 779#define nm_stld_barrier smp_mb 780#else /* !__KERNEL__ */ 781static inline void nm_stst_barrier(void) 782{ 783 /* A memory barrier with release semantic has the combined 784 * effect of a store-store barrier and a load-store barrier, 785 * which is fine for us. */ 786 __atomic_thread_fence(__ATOMIC_RELEASE); 787} 788static inline void nm_ldld_barrier(void) 789{ 790 /* A memory barrier with acquire semantic has the combined 791 * effect of a load-load barrier and a store-load barrier, 792 * which is fine for us. */ 793 __atomic_thread_fence(__ATOMIC_ACQUIRE); 794} 795#endif /* !__KERNEL__ */ 796 797#elif defined(__FreeBSD__) 798 799#ifdef _KERNEL 800#define nm_stst_barrier atomic_thread_fence_rel 801#define nm_ldld_barrier atomic_thread_fence_acq 802#define nm_stld_barrier atomic_thread_fence_seq_cst 803#else /* !_KERNEL */ 804#include <stdatomic.h> 805static inline void nm_stst_barrier(void) 806{ 807 atomic_thread_fence(memory_order_release); 808} 809static inline void nm_ldld_barrier(void) 810{ 811 atomic_thread_fence(memory_order_acquire); 812} 813#endif /* !_KERNEL */ 814 815#else /* !__linux__ && !__FreeBSD__ */ 816#error "OS not supported" 817#endif /* !__linux__ && !__FreeBSD__ */ 818 819/* Application side of sync-kloop: Write ring pointers (cur, head) to the CSB. 820 * This routine is coupled with sync_kloop_kernel_read(). */ 821static inline void 822nm_sync_kloop_appl_write(struct nm_csb_atok *atok, uint32_t cur, 823 uint32_t head) 824{ 825 /* Issue a first store-store barrier to make sure writes to the 826 * netmap ring do not overcome updates on atok->cur and atok->head. */ 827 nm_stst_barrier(); 828 829 /* 830 * We need to write cur and head to the CSB but we cannot do it atomically. 831 * There is no way we can prevent the host from reading the updated value 832 * of one of the two and the old value of the other. However, if we make 833 * sure that the host never reads a value of head more recent than the 834 * value of cur we are safe. We can allow the host to read a value of cur 835 * more recent than the value of head, since in the netmap ring cur can be 836 * ahead of head and cur cannot wrap around head because it must be behind 837 * tail. Inverting the order of writes below could instead result into the 838 * host to think head went ahead of cur, which would cause the sync 839 * prologue to fail. 840 * 841 * The following memory barrier scheme is used to make this happen: 842 * 843 * Guest Host 844 * 845 * STORE(cur) LOAD(head) 846 * wmb() <-----------> rmb() 847 * STORE(head) LOAD(cur) 848 * 849 */ 850 atok->cur = cur; 851 nm_stst_barrier(); 852 atok->head = head; 853} 854 855/* Application side of sync-kloop: Read kring pointers (hwcur, hwtail) from 856 * the CSB. This routine is coupled with sync_kloop_kernel_write(). */ 857static inline void 858nm_sync_kloop_appl_read(struct nm_csb_ktoa *ktoa, uint32_t *hwtail, 859 uint32_t *hwcur) 860{ 861 /* 862 * We place a memory barrier to make sure that the update of hwtail never 863 * overtakes the update of hwcur. 864 * (see explanation in sync_kloop_kernel_write). 865 */ 866 *hwtail = ktoa->hwtail; 867 nm_ldld_barrier(); 868 *hwcur = ktoa->hwcur; 869 870 /* Make sure that loads from ktoa->hwtail and ktoa->hwcur are not delayed 871 * after the loads from the netmap ring. */ 872 nm_ldld_barrier(); 873} 874 875/* 876 * data for NETMAP_REQ_OPT_* options 877 */ 878 879struct nmreq_opt_sync_kloop_eventfds { 880 struct nmreq_option nro_opt; /* common header */ 881 /* An array of N entries for bidirectional notifications between 882 * the kernel loop and the application. The number of entries and 883 * their order must agree with the CSB arrays passed in the 884 * NETMAP_REQ_OPT_CSB option. Each entry contains a file descriptor 885 * backed by an eventfd. 886 * 887 * If any of the 'ioeventfd' entries is < 0, the event loop uses 888 * the sleeping synchronization strategy (according to sleep_us), 889 * and keeps kern_need_kick always disabled. 890 * Each 'irqfd' can be < 0, and in that case the corresponding queue 891 * is never notified. 892 */ 893 struct { 894 /* Notifier for the application --> kernel loop direction. */ 895 int32_t ioeventfd; 896 /* Notifier for the kernel loop --> application direction. */ 897 int32_t irqfd; 898 } eventfds[0]; 899}; 900 901struct nmreq_opt_sync_kloop_mode { 902 struct nmreq_option nro_opt; /* common header */ 903#define NM_OPT_SYNC_KLOOP_DIRECT_TX (1 << 0) 904#define NM_OPT_SYNC_KLOOP_DIRECT_RX (1 << 1) 905 uint32_t mode; 906}; 907 908struct nmreq_opt_extmem { 909 struct nmreq_option nro_opt; /* common header */ 910 uint64_t nro_usrptr; /* (in) ptr to usr memory */ 911 struct nmreq_pools_info nro_info; /* (in/out) */ 912}; 913 914struct nmreq_opt_csb { 915 struct nmreq_option nro_opt; 916 917 /* Array of CSB entries for application --> kernel communication 918 * (N entries). */ 919 uint64_t csb_atok; 920 921 /* Array of CSB entries for kernel --> application communication 922 * (N entries). */ 923 uint64_t csb_ktoa; 924}; 925 926#endif /* _NET_NETMAP_H_ */ 927