1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * VMware VMCI Driver 4 * 5 * Copyright (C) 2012 VMware, Inc. All rights reserved. 6 */ 7 8 #ifndef _VMW_VMCI_DEF_H_ 9 #define _VMW_VMCI_DEF_H_ 10 11 #include <linux/atomic.h> 12 #include <linux/bits.h> 13 14 /* Register offsets. */ 15 #define VMCI_STATUS_ADDR 0x00 16 #define VMCI_CONTROL_ADDR 0x04 17 #define VMCI_ICR_ADDR 0x08 18 #define VMCI_IMR_ADDR 0x0c 19 #define VMCI_DATA_OUT_ADDR 0x10 20 #define VMCI_DATA_IN_ADDR 0x14 21 #define VMCI_CAPS_ADDR 0x18 22 #define VMCI_RESULT_LOW_ADDR 0x1c 23 #define VMCI_RESULT_HIGH_ADDR 0x20 24 #define VMCI_DATA_OUT_LOW_ADDR 0x24 25 #define VMCI_DATA_OUT_HIGH_ADDR 0x28 26 #define VMCI_DATA_IN_LOW_ADDR 0x2c 27 #define VMCI_DATA_IN_HIGH_ADDR 0x30 28 #define VMCI_GUEST_PAGE_SHIFT 0x34 29 30 /* Max number of devices. */ 31 #define VMCI_MAX_DEVICES 1 32 33 /* Status register bits. */ 34 #define VMCI_STATUS_INT_ON BIT(0) 35 36 /* Control register bits. */ 37 #define VMCI_CONTROL_RESET BIT(0) 38 #define VMCI_CONTROL_INT_ENABLE BIT(1) 39 #define VMCI_CONTROL_INT_DISABLE BIT(2) 40 41 /* Capabilities register bits. */ 42 #define VMCI_CAPS_HYPERCALL BIT(0) 43 #define VMCI_CAPS_GUESTCALL BIT(1) 44 #define VMCI_CAPS_DATAGRAM BIT(2) 45 #define VMCI_CAPS_NOTIFICATIONS BIT(3) 46 #define VMCI_CAPS_PPN64 BIT(4) 47 #define VMCI_CAPS_DMA_DATAGRAM BIT(5) 48 49 /* Interrupt Cause register bits. */ 50 #define VMCI_ICR_DATAGRAM BIT(0) 51 #define VMCI_ICR_NOTIFICATION BIT(1) 52 #define VMCI_ICR_DMA_DATAGRAM BIT(2) 53 54 /* Interrupt Mask register bits. */ 55 #define VMCI_IMR_DATAGRAM BIT(0) 56 #define VMCI_IMR_NOTIFICATION BIT(1) 57 #define VMCI_IMR_DMA_DATAGRAM BIT(2) 58 59 /* 60 * Maximum MSI/MSI-X interrupt vectors in the device. 61 * If VMCI_CAPS_DMA_DATAGRAM is supported by the device, 62 * VMCI_MAX_INTRS_DMA_DATAGRAM vectors are available, 63 * otherwise only VMCI_MAX_INTRS_NOTIFICATION. 64 */ 65 #define VMCI_MAX_INTRS_NOTIFICATION 2 66 #define VMCI_MAX_INTRS_DMA_DATAGRAM 3 67 #define VMCI_MAX_INTRS VMCI_MAX_INTRS_DMA_DATAGRAM 68 69 /* 70 * Supported interrupt vectors. There is one for each ICR value above, 71 * but here they indicate the position in the vector array/message ID. 72 */ 73 enum { 74 VMCI_INTR_DATAGRAM = 0, 75 VMCI_INTR_NOTIFICATION = 1, 76 VMCI_INTR_DMA_DATAGRAM = 2, 77 }; 78 79 /* 80 * A single VMCI device has an upper limit of 128MB on the amount of 81 * memory that can be used for queue pairs. Since each queue pair 82 * consists of at least two pages, the memory limit also dictates the 83 * number of queue pairs a guest can create. 84 */ 85 #define VMCI_MAX_GUEST_QP_MEMORY ((size_t)(128 * 1024 * 1024)) 86 #define VMCI_MAX_GUEST_QP_COUNT (VMCI_MAX_GUEST_QP_MEMORY / PAGE_SIZE / 2) 87 88 /* 89 * There can be at most PAGE_SIZE doorbells since there is one doorbell 90 * per byte in the doorbell bitmap page. 91 */ 92 #define VMCI_MAX_GUEST_DOORBELL_COUNT PAGE_SIZE 93 94 /* 95 * Queues with pre-mapped data pages must be small, so that we don't pin 96 * too much kernel memory (especially on vmkernel). We limit a queuepair to 97 * 32 KB, or 16 KB per queue for symmetrical pairs. 98 */ 99 #define VMCI_MAX_PINNED_QP_MEMORY ((size_t)(32 * 1024)) 100 101 /* 102 * The version of the VMCI device that supports MMIO access to registers 103 * requests 256KB for BAR1 whereas the version of VMCI that supports 104 * MSI/MSI-X only requests 8KB. The layout of the larger 256KB region is: 105 * - the first 128KB are used for MSI/MSI-X. 106 * - the following 64KB are used for MMIO register access. 107 * - the remaining 64KB are unused. 108 */ 109 #define VMCI_WITH_MMIO_ACCESS_BAR_SIZE ((size_t)(256 * 1024)) 110 #define VMCI_MMIO_ACCESS_OFFSET ((size_t)(128 * 1024)) 111 #define VMCI_MMIO_ACCESS_SIZE ((size_t)(64 * 1024)) 112 113 /* 114 * For VMCI devices supporting the VMCI_CAPS_DMA_DATAGRAM capability, the 115 * sending and receiving of datagrams can be performed using DMA to/from 116 * a driver allocated buffer. 117 * Sending and receiving will be handled as follows: 118 * - when sending datagrams, the driver initializes the buffer where the 119 * data part will refer to the outgoing VMCI datagram, sets the busy flag 120 * to 1 and writes the address of the buffer to VMCI_DATA_OUT_HIGH_ADDR 121 * and VMCI_DATA_OUT_LOW_ADDR. Writing to VMCI_DATA_OUT_LOW_ADDR triggers 122 * the device processing of the buffer. When the device has processed the 123 * buffer, it will write the result value to the buffer and then clear the 124 * busy flag. 125 * - when receiving datagrams, the driver initializes the buffer where the 126 * data part will describe the receive buffer, clears the busy flag and 127 * writes the address of the buffer to VMCI_DATA_IN_HIGH_ADDR and 128 * VMCI_DATA_IN_LOW_ADDR. Writing to VMCI_DATA_IN_LOW_ADDR triggers the 129 * device processing of the buffer. The device will copy as many available 130 * datagrams into the buffer as possible, and then sets the busy flag. 131 * When the busy flag is set, the driver will process the datagrams in the 132 * buffer. 133 */ 134 struct vmci_data_in_out_header { 135 uint32_t busy; 136 uint32_t opcode; 137 uint32_t size; 138 uint32_t rsvd; 139 uint64_t result; 140 }; 141 142 struct vmci_sg_elem { 143 uint64_t addr; 144 uint64_t size; 145 }; 146 147 /* 148 * We have a fixed set of resource IDs available in the VMX. 149 * This allows us to have a very simple implementation since we statically 150 * know how many will create datagram handles. If a new caller arrives and 151 * we have run out of slots we can manually increment the maximum size of 152 * available resource IDs. 153 * 154 * VMCI reserved hypervisor datagram resource IDs. 155 */ 156 enum { 157 VMCI_RESOURCES_QUERY = 0, 158 VMCI_GET_CONTEXT_ID = 1, 159 VMCI_SET_NOTIFY_BITMAP = 2, 160 VMCI_DOORBELL_LINK = 3, 161 VMCI_DOORBELL_UNLINK = 4, 162 VMCI_DOORBELL_NOTIFY = 5, 163 /* 164 * VMCI_DATAGRAM_REQUEST_MAP and VMCI_DATAGRAM_REMOVE_MAP are 165 * obsoleted by the removal of VM to VM communication. 166 */ 167 VMCI_DATAGRAM_REQUEST_MAP = 6, 168 VMCI_DATAGRAM_REMOVE_MAP = 7, 169 VMCI_EVENT_SUBSCRIBE = 8, 170 VMCI_EVENT_UNSUBSCRIBE = 9, 171 VMCI_QUEUEPAIR_ALLOC = 10, 172 VMCI_QUEUEPAIR_DETACH = 11, 173 174 /* 175 * VMCI_VSOCK_VMX_LOOKUP was assigned to 12 for Fusion 3.0/3.1, 176 * WS 7.0/7.1 and ESX 4.1 177 */ 178 VMCI_HGFS_TRANSPORT = 13, 179 VMCI_UNITY_PBRPC_REGISTER = 14, 180 VMCI_RPC_PRIVILEGED = 15, 181 VMCI_RPC_UNPRIVILEGED = 16, 182 VMCI_RESOURCE_MAX = 17, 183 }; 184 185 /* 186 * struct vmci_handle - Ownership information structure 187 * @context: The VMX context ID. 188 * @resource: The resource ID (used for locating in resource hash). 189 * 190 * The vmci_handle structure is used to track resources used within 191 * vmw_vmci. 192 */ 193 struct vmci_handle { 194 u32 context; 195 u32 resource; 196 }; 197 198 #define vmci_make_handle(_cid, _rid) \ 199 (struct vmci_handle){ .context = _cid, .resource = _rid } 200 201 static inline bool vmci_handle_is_equal(struct vmci_handle h1, 202 struct vmci_handle h2) 203 { 204 return h1.context == h2.context && h1.resource == h2.resource; 205 } 206 207 #define VMCI_INVALID_ID ~0 208 static const struct vmci_handle VMCI_INVALID_HANDLE = { 209 .context = VMCI_INVALID_ID, 210 .resource = VMCI_INVALID_ID 211 }; 212 213 static inline bool vmci_handle_is_invalid(struct vmci_handle h) 214 { 215 return vmci_handle_is_equal(h, VMCI_INVALID_HANDLE); 216 } 217 218 /* 219 * The below defines can be used to send anonymous requests. 220 * This also indicates that no response is expected. 221 */ 222 #define VMCI_ANON_SRC_CONTEXT_ID VMCI_INVALID_ID 223 #define VMCI_ANON_SRC_RESOURCE_ID VMCI_INVALID_ID 224 static const struct vmci_handle __maybe_unused VMCI_ANON_SRC_HANDLE = { 225 .context = VMCI_ANON_SRC_CONTEXT_ID, 226 .resource = VMCI_ANON_SRC_RESOURCE_ID 227 }; 228 229 /* The lowest 16 context ids are reserved for internal use. */ 230 #define VMCI_RESERVED_CID_LIMIT ((u32) 16) 231 232 /* 233 * Hypervisor context id, used for calling into hypervisor 234 * supplied services from the VM. 235 */ 236 #define VMCI_HYPERVISOR_CONTEXT_ID 0 237 238 /* 239 * Well-known context id, a logical context that contains a set of 240 * well-known services. This context ID is now obsolete. 241 */ 242 #define VMCI_WELL_KNOWN_CONTEXT_ID 1 243 244 /* 245 * Context ID used by host endpoints. 246 */ 247 #define VMCI_HOST_CONTEXT_ID 2 248 249 #define VMCI_CONTEXT_IS_VM(_cid) (VMCI_INVALID_ID != (_cid) && \ 250 (_cid) > VMCI_HOST_CONTEXT_ID) 251 252 /* 253 * The VMCI_CONTEXT_RESOURCE_ID is used together with vmci_make_handle to make 254 * handles that refer to a specific context. 255 */ 256 #define VMCI_CONTEXT_RESOURCE_ID 0 257 258 /* 259 * VMCI error codes. 260 */ 261 enum { 262 VMCI_SUCCESS_QUEUEPAIR_ATTACH = 5, 263 VMCI_SUCCESS_QUEUEPAIR_CREATE = 4, 264 VMCI_SUCCESS_LAST_DETACH = 3, 265 VMCI_SUCCESS_ACCESS_GRANTED = 2, 266 VMCI_SUCCESS_ENTRY_DEAD = 1, 267 VMCI_SUCCESS = 0, 268 VMCI_ERROR_INVALID_RESOURCE = (-1), 269 VMCI_ERROR_INVALID_ARGS = (-2), 270 VMCI_ERROR_NO_MEM = (-3), 271 VMCI_ERROR_DATAGRAM_FAILED = (-4), 272 VMCI_ERROR_MORE_DATA = (-5), 273 VMCI_ERROR_NO_MORE_DATAGRAMS = (-6), 274 VMCI_ERROR_NO_ACCESS = (-7), 275 VMCI_ERROR_NO_HANDLE = (-8), 276 VMCI_ERROR_DUPLICATE_ENTRY = (-9), 277 VMCI_ERROR_DST_UNREACHABLE = (-10), 278 VMCI_ERROR_PAYLOAD_TOO_LARGE = (-11), 279 VMCI_ERROR_INVALID_PRIV = (-12), 280 VMCI_ERROR_GENERIC = (-13), 281 VMCI_ERROR_PAGE_ALREADY_SHARED = (-14), 282 VMCI_ERROR_CANNOT_SHARE_PAGE = (-15), 283 VMCI_ERROR_CANNOT_UNSHARE_PAGE = (-16), 284 VMCI_ERROR_NO_PROCESS = (-17), 285 VMCI_ERROR_NO_DATAGRAM = (-18), 286 VMCI_ERROR_NO_RESOURCES = (-19), 287 VMCI_ERROR_UNAVAILABLE = (-20), 288 VMCI_ERROR_NOT_FOUND = (-21), 289 VMCI_ERROR_ALREADY_EXISTS = (-22), 290 VMCI_ERROR_NOT_PAGE_ALIGNED = (-23), 291 VMCI_ERROR_INVALID_SIZE = (-24), 292 VMCI_ERROR_REGION_ALREADY_SHARED = (-25), 293 VMCI_ERROR_TIMEOUT = (-26), 294 VMCI_ERROR_DATAGRAM_INCOMPLETE = (-27), 295 VMCI_ERROR_INCORRECT_IRQL = (-28), 296 VMCI_ERROR_EVENT_UNKNOWN = (-29), 297 VMCI_ERROR_OBSOLETE = (-30), 298 VMCI_ERROR_QUEUEPAIR_MISMATCH = (-31), 299 VMCI_ERROR_QUEUEPAIR_NOTSET = (-32), 300 VMCI_ERROR_QUEUEPAIR_NOTOWNER = (-33), 301 VMCI_ERROR_QUEUEPAIR_NOTATTACHED = (-34), 302 VMCI_ERROR_QUEUEPAIR_NOSPACE = (-35), 303 VMCI_ERROR_QUEUEPAIR_NODATA = (-36), 304 VMCI_ERROR_BUSMEM_INVALIDATION = (-37), 305 VMCI_ERROR_MODULE_NOT_LOADED = (-38), 306 VMCI_ERROR_DEVICE_NOT_FOUND = (-39), 307 VMCI_ERROR_QUEUEPAIR_NOT_READY = (-40), 308 VMCI_ERROR_WOULD_BLOCK = (-41), 309 310 /* VMCI clients should return error code within this range */ 311 VMCI_ERROR_CLIENT_MIN = (-500), 312 VMCI_ERROR_CLIENT_MAX = (-550), 313 314 /* Internal error codes. */ 315 VMCI_SHAREDMEM_ERROR_BAD_CONTEXT = (-1000), 316 }; 317 318 /* VMCI reserved events. */ 319 enum { 320 /* Only applicable to guest endpoints */ 321 VMCI_EVENT_CTX_ID_UPDATE = 0, 322 323 /* Applicable to guest and host */ 324 VMCI_EVENT_CTX_REMOVED = 1, 325 326 /* Only applicable to guest endpoints */ 327 VMCI_EVENT_QP_RESUMED = 2, 328 329 /* Applicable to guest and host */ 330 VMCI_EVENT_QP_PEER_ATTACH = 3, 331 332 /* Applicable to guest and host */ 333 VMCI_EVENT_QP_PEER_DETACH = 4, 334 335 /* 336 * Applicable to VMX and vmk. On vmk, 337 * this event has the Context payload type. 338 */ 339 VMCI_EVENT_MEM_ACCESS_ON = 5, 340 341 /* 342 * Applicable to VMX and vmk. Same as 343 * above for the payload type. 344 */ 345 VMCI_EVENT_MEM_ACCESS_OFF = 6, 346 VMCI_EVENT_MAX = 7, 347 }; 348 349 /* 350 * Of the above events, a few are reserved for use in the VMX, and 351 * other endpoints (guest and host kernel) should not use them. For 352 * the rest of the events, we allow both host and guest endpoints to 353 * subscribe to them, to maintain the same API for host and guest 354 * endpoints. 355 */ 356 #define VMCI_EVENT_VALID_VMX(_event) ((_event) == VMCI_EVENT_MEM_ACCESS_ON || \ 357 (_event) == VMCI_EVENT_MEM_ACCESS_OFF) 358 359 #define VMCI_EVENT_VALID(_event) ((_event) < VMCI_EVENT_MAX && \ 360 !VMCI_EVENT_VALID_VMX(_event)) 361 362 /* Reserved guest datagram resource ids. */ 363 #define VMCI_EVENT_HANDLER 0 364 365 /* 366 * VMCI coarse-grained privileges (per context or host 367 * process/endpoint. An entity with the restricted flag is only 368 * allowed to interact with the hypervisor and trusted entities. 369 */ 370 enum { 371 VMCI_NO_PRIVILEGE_FLAGS = 0, 372 VMCI_PRIVILEGE_FLAG_RESTRICTED = 1, 373 VMCI_PRIVILEGE_FLAG_TRUSTED = 2, 374 VMCI_PRIVILEGE_ALL_FLAGS = (VMCI_PRIVILEGE_FLAG_RESTRICTED | 375 VMCI_PRIVILEGE_FLAG_TRUSTED), 376 VMCI_DEFAULT_PROC_PRIVILEGE_FLAGS = VMCI_NO_PRIVILEGE_FLAGS, 377 VMCI_LEAST_PRIVILEGE_FLAGS = VMCI_PRIVILEGE_FLAG_RESTRICTED, 378 VMCI_MAX_PRIVILEGE_FLAGS = VMCI_PRIVILEGE_FLAG_TRUSTED, 379 }; 380 381 /* 0 through VMCI_RESERVED_RESOURCE_ID_MAX are reserved. */ 382 #define VMCI_RESERVED_RESOURCE_ID_MAX 1023 383 384 /* 385 * Driver version. 386 * 387 * Increment major version when you make an incompatible change. 388 * Compatibility goes both ways (old driver with new executable 389 * as well as new driver with old executable). 390 */ 391 392 /* Never change VMCI_VERSION_SHIFT_WIDTH */ 393 #define VMCI_VERSION_SHIFT_WIDTH 16 394 #define VMCI_MAKE_VERSION(_major, _minor) \ 395 ((_major) << VMCI_VERSION_SHIFT_WIDTH | (u16) (_minor)) 396 397 #define VMCI_VERSION_MAJOR(v) ((u32) (v) >> VMCI_VERSION_SHIFT_WIDTH) 398 #define VMCI_VERSION_MINOR(v) ((u16) (v)) 399 400 /* 401 * VMCI_VERSION is always the current version. Subsequently listed 402 * versions are ways of detecting previous versions of the connecting 403 * application (i.e., VMX). 404 * 405 * VMCI_VERSION_NOVMVM: This version removed support for VM to VM 406 * communication. 407 * 408 * VMCI_VERSION_NOTIFY: This version introduced doorbell notification 409 * support. 410 * 411 * VMCI_VERSION_HOSTQP: This version introduced host end point support 412 * for hosted products. 413 * 414 * VMCI_VERSION_PREHOSTQP: This is the version prior to the adoption of 415 * support for host end-points. 416 * 417 * VMCI_VERSION_PREVERS2: This fictional version number is intended to 418 * represent the version of a VMX which doesn't call into the driver 419 * with ioctl VERSION2 and thus doesn't establish its version with the 420 * driver. 421 */ 422 423 #define VMCI_VERSION VMCI_VERSION_NOVMVM 424 #define VMCI_VERSION_NOVMVM VMCI_MAKE_VERSION(11, 0) 425 #define VMCI_VERSION_NOTIFY VMCI_MAKE_VERSION(10, 0) 426 #define VMCI_VERSION_HOSTQP VMCI_MAKE_VERSION(9, 0) 427 #define VMCI_VERSION_PREHOSTQP VMCI_MAKE_VERSION(8, 0) 428 #define VMCI_VERSION_PREVERS2 VMCI_MAKE_VERSION(1, 0) 429 430 #define VMCI_SOCKETS_MAKE_VERSION(_p) \ 431 ((((_p)[0] & 0xFF) << 24) | (((_p)[1] & 0xFF) << 16) | ((_p)[2])) 432 433 /* 434 * The VMCI IOCTLs. We use identity code 7, as noted in ioctl-number.rst, 435 * and we start at sequence 9f. This gives us the same values that our 436 * shipping products use, starting at 1951, provided we leave out the 437 * direction and structure size. Note that VMMon occupies the block 438 * following us, starting at 2001. 439 */ 440 #define IOCTL_VMCI_VERSION _IO(7, 0x9f) /* 1951 */ 441 #define IOCTL_VMCI_INIT_CONTEXT _IO(7, 0xa0) 442 #define IOCTL_VMCI_QUEUEPAIR_SETVA _IO(7, 0xa4) 443 #define IOCTL_VMCI_NOTIFY_RESOURCE _IO(7, 0xa5) 444 #define IOCTL_VMCI_NOTIFICATIONS_RECEIVE _IO(7, 0xa6) 445 #define IOCTL_VMCI_VERSION2 _IO(7, 0xa7) 446 #define IOCTL_VMCI_QUEUEPAIR_ALLOC _IO(7, 0xa8) 447 #define IOCTL_VMCI_QUEUEPAIR_SETPAGEFILE _IO(7, 0xa9) 448 #define IOCTL_VMCI_QUEUEPAIR_DETACH _IO(7, 0xaa) 449 #define IOCTL_VMCI_DATAGRAM_SEND _IO(7, 0xab) 450 #define IOCTL_VMCI_DATAGRAM_RECEIVE _IO(7, 0xac) 451 #define IOCTL_VMCI_CTX_ADD_NOTIFICATION _IO(7, 0xaf) 452 #define IOCTL_VMCI_CTX_REMOVE_NOTIFICATION _IO(7, 0xb0) 453 #define IOCTL_VMCI_CTX_GET_CPT_STATE _IO(7, 0xb1) 454 #define IOCTL_VMCI_CTX_SET_CPT_STATE _IO(7, 0xb2) 455 #define IOCTL_VMCI_GET_CONTEXT_ID _IO(7, 0xb3) 456 /*IOCTL_VM_SOCKETS_GET_LOCAL_CID _IO(7, 0xb9)*/ 457 #define IOCTL_VMCI_SET_NOTIFY _IO(7, 0xcb) /* 1995 */ 458 /*IOCTL_VMMON_START _IO(7, 0xd1)*/ /* 2001 */ 459 460 /* 461 * struct vmci_queue_header - VMCI Queue Header information. 462 * 463 * A Queue cannot stand by itself as designed. Each Queue's header 464 * contains a pointer into itself (the producer_tail) and into its peer 465 * (consumer_head). The reason for the separation is one of 466 * accessibility: Each end-point can modify two things: where the next 467 * location to enqueue is within its produce_q (producer_tail); and 468 * where the next dequeue location is in its consume_q (consumer_head). 469 * 470 * An end-point cannot modify the pointers of its peer (guest to 471 * guest; NOTE that in the host both queue headers are mapped r/w). 472 * But, each end-point needs read access to both Queue header 473 * structures in order to determine how much space is used (or left) 474 * in the Queue. This is because for an end-point to know how full 475 * its produce_q is, it needs to use the consumer_head that points into 476 * the produce_q but -that- consumer_head is in the Queue header for 477 * that end-points consume_q. 478 * 479 * Thoroughly confused? Sorry. 480 * 481 * producer_tail: the point to enqueue new entrants. When you approach 482 * a line in a store, for example, you walk up to the tail. 483 * 484 * consumer_head: the point in the queue from which the next element is 485 * dequeued. In other words, who is next in line is he who is at the 486 * head of the line. 487 * 488 * Also, producer_tail points to an empty byte in the Queue, whereas 489 * consumer_head points to a valid byte of data (unless producer_tail == 490 * consumer_head in which case consumer_head does not point to a valid 491 * byte of data). 492 * 493 * For a queue of buffer 'size' bytes, the tail and head pointers will be in 494 * the range [0, size-1]. 495 * 496 * If produce_q_header->producer_tail == consume_q_header->consumer_head 497 * then the produce_q is empty. 498 */ 499 struct vmci_queue_header { 500 /* All fields are 64bit and aligned. */ 501 struct vmci_handle handle; /* Identifier. */ 502 u64 producer_tail; /* Offset in this queue. */ 503 u64 consumer_head; /* Offset in peer queue. */ 504 }; 505 506 /* 507 * struct vmci_datagram - Base struct for vmci datagrams. 508 * @dst: A vmci_handle that tracks the destination of the datagram. 509 * @src: A vmci_handle that tracks the source of the datagram. 510 * @payload_size: The size of the payload. 511 * 512 * vmci_datagram structs are used when sending vmci datagrams. They include 513 * the necessary source and destination information to properly route 514 * the information along with the size of the package. 515 */ 516 struct vmci_datagram { 517 struct vmci_handle dst; 518 struct vmci_handle src; 519 u64 payload_size; 520 }; 521 522 /* 523 * Second flag is for creating a well-known handle instead of a per context 524 * handle. Next flag is for deferring datagram delivery, so that the 525 * datagram callback is invoked in a delayed context (not interrupt context). 526 */ 527 #define VMCI_FLAG_DG_NONE 0 528 #define VMCI_FLAG_WELLKNOWN_DG_HND BIT(0) 529 #define VMCI_FLAG_ANYCID_DG_HND BIT(1) 530 #define VMCI_FLAG_DG_DELAYED_CB BIT(2) 531 532 /* 533 * Maximum supported size of a VMCI datagram for routable datagrams. 534 * Datagrams going to the hypervisor are allowed to be larger. 535 */ 536 #define VMCI_MAX_DG_SIZE (17 * 4096) 537 #define VMCI_MAX_DG_PAYLOAD_SIZE (VMCI_MAX_DG_SIZE - \ 538 sizeof(struct vmci_datagram)) 539 #define VMCI_DG_PAYLOAD(_dg) (void *)((char *)(_dg) + \ 540 sizeof(struct vmci_datagram)) 541 #define VMCI_DG_HEADERSIZE sizeof(struct vmci_datagram) 542 #define VMCI_DG_SIZE(_dg) (VMCI_DG_HEADERSIZE + (size_t)(_dg)->payload_size) 543 #define VMCI_DG_SIZE_ALIGNED(_dg) ((VMCI_DG_SIZE(_dg) + 7) & (~((size_t) 0x7))) 544 #define VMCI_MAX_DATAGRAM_QUEUE_SIZE (VMCI_MAX_DG_SIZE * 2) 545 546 struct vmci_event_payload_qp { 547 struct vmci_handle handle; /* queue_pair handle. */ 548 u32 peer_id; /* Context id of attaching/detaching VM. */ 549 u32 _pad; 550 }; 551 552 /* Flags for VMCI queue_pair API. */ 553 enum { 554 /* Fail alloc if QP not created by peer. */ 555 VMCI_QPFLAG_ATTACH_ONLY = 1 << 0, 556 557 /* Only allow attaches from local context. */ 558 VMCI_QPFLAG_LOCAL = 1 << 1, 559 560 /* Host won't block when guest is quiesced. */ 561 VMCI_QPFLAG_NONBLOCK = 1 << 2, 562 563 /* Pin data pages in ESX. Used with NONBLOCK */ 564 VMCI_QPFLAG_PINNED = 1 << 3, 565 566 /* Update the following flag when adding new flags. */ 567 VMCI_QP_ALL_FLAGS = (VMCI_QPFLAG_ATTACH_ONLY | VMCI_QPFLAG_LOCAL | 568 VMCI_QPFLAG_NONBLOCK | VMCI_QPFLAG_PINNED), 569 570 /* Convenience flags */ 571 VMCI_QP_ASYMM = (VMCI_QPFLAG_NONBLOCK | VMCI_QPFLAG_PINNED), 572 VMCI_QP_ASYMM_PEER = (VMCI_QPFLAG_ATTACH_ONLY | VMCI_QP_ASYMM), 573 }; 574 575 /* 576 * We allow at least 1024 more event datagrams from the hypervisor past the 577 * normally allowed datagrams pending for a given context. We define this 578 * limit on event datagrams from the hypervisor to guard against DoS attack 579 * from a malicious VM which could repeatedly attach to and detach from a queue 580 * pair, causing events to be queued at the destination VM. However, the rate 581 * at which such events can be generated is small since it requires a VM exit 582 * and handling of queue pair attach/detach call at the hypervisor. Event 583 * datagrams may be queued up at the destination VM if it has interrupts 584 * disabled or if it is not draining events for some other reason. 1024 585 * datagrams is a grossly conservative estimate of the time for which 586 * interrupts may be disabled in the destination VM, but at the same time does 587 * not exacerbate the memory pressure problem on the host by much (size of each 588 * event datagram is small). 589 */ 590 #define VMCI_MAX_DATAGRAM_AND_EVENT_QUEUE_SIZE \ 591 (VMCI_MAX_DATAGRAM_QUEUE_SIZE + \ 592 1024 * (sizeof(struct vmci_datagram) + \ 593 sizeof(struct vmci_event_data_max))) 594 595 /* 596 * Struct used for querying, via VMCI_RESOURCES_QUERY, the availability of 597 * hypervisor resources. Struct size is 16 bytes. All fields in struct are 598 * aligned to their natural alignment. 599 */ 600 struct vmci_resource_query_hdr { 601 struct vmci_datagram hdr; 602 u32 num_resources; 603 u32 _padding; 604 }; 605 606 /* 607 * Convenience struct for negotiating vectors. Must match layout of 608 * VMCIResourceQueryHdr minus the struct vmci_datagram header. 609 */ 610 struct vmci_resource_query_msg { 611 u32 num_resources; 612 u32 _padding; 613 u32 resources[1]; 614 }; 615 616 /* 617 * The maximum number of resources that can be queried using 618 * VMCI_RESOURCE_QUERY is 31, as the result is encoded in the lower 31 619 * bits of a positive return value. Negative values are reserved for 620 * errors. 621 */ 622 #define VMCI_RESOURCE_QUERY_MAX_NUM 31 623 624 /* Maximum size for the VMCI_RESOURCE_QUERY request. */ 625 #define VMCI_RESOURCE_QUERY_MAX_SIZE \ 626 (sizeof(struct vmci_resource_query_hdr) + \ 627 sizeof(u32) * VMCI_RESOURCE_QUERY_MAX_NUM) 628 629 /* 630 * Struct used for setting the notification bitmap. All fields in 631 * struct are aligned to their natural alignment. 632 */ 633 struct vmci_notify_bm_set_msg { 634 struct vmci_datagram hdr; 635 union { 636 u32 bitmap_ppn32; 637 u64 bitmap_ppn64; 638 }; 639 }; 640 641 /* 642 * Struct used for linking a doorbell handle with an index in the 643 * notify bitmap. All fields in struct are aligned to their natural 644 * alignment. 645 */ 646 struct vmci_doorbell_link_msg { 647 struct vmci_datagram hdr; 648 struct vmci_handle handle; 649 u64 notify_idx; 650 }; 651 652 /* 653 * Struct used for unlinking a doorbell handle from an index in the 654 * notify bitmap. All fields in struct are aligned to their natural 655 * alignment. 656 */ 657 struct vmci_doorbell_unlink_msg { 658 struct vmci_datagram hdr; 659 struct vmci_handle handle; 660 }; 661 662 /* 663 * Struct used for generating a notification on a doorbell handle. All 664 * fields in struct are aligned to their natural alignment. 665 */ 666 struct vmci_doorbell_notify_msg { 667 struct vmci_datagram hdr; 668 struct vmci_handle handle; 669 }; 670 671 /* 672 * This struct is used to contain data for events. Size of this struct is a 673 * multiple of 8 bytes, and all fields are aligned to their natural alignment. 674 */ 675 struct vmci_event_data { 676 u32 event; /* 4 bytes. */ 677 u32 _pad; 678 /* Event payload is put here. */ 679 }; 680 681 /* 682 * Define the different VMCI_EVENT payload data types here. All structs must 683 * be a multiple of 8 bytes, and fields must be aligned to their natural 684 * alignment. 685 */ 686 struct vmci_event_payld_ctx { 687 u32 context_id; /* 4 bytes. */ 688 u32 _pad; 689 }; 690 691 struct vmci_event_payld_qp { 692 struct vmci_handle handle; /* queue_pair handle. */ 693 u32 peer_id; /* Context id of attaching/detaching VM. */ 694 u32 _pad; 695 }; 696 697 /* 698 * We define the following struct to get the size of the maximum event 699 * data the hypervisor may send to the guest. If adding a new event 700 * payload type above, add it to the following struct too (inside the 701 * union). 702 */ 703 struct vmci_event_data_max { 704 struct vmci_event_data event_data; 705 union { 706 struct vmci_event_payld_ctx context_payload; 707 struct vmci_event_payld_qp qp_payload; 708 } ev_data_payload; 709 }; 710 711 /* 712 * Struct used for VMCI_EVENT_SUBSCRIBE/UNSUBSCRIBE and 713 * VMCI_EVENT_HANDLER messages. Struct size is 32 bytes. All fields 714 * in struct are aligned to their natural alignment. 715 */ 716 struct vmci_event_msg { 717 struct vmci_datagram hdr; 718 719 /* Has event type and payload. */ 720 struct vmci_event_data event_data; 721 722 /* Payload gets put here. */ 723 }; 724 725 /* Event with context payload. */ 726 struct vmci_event_ctx { 727 struct vmci_event_msg msg; 728 struct vmci_event_payld_ctx payload; 729 }; 730 731 /* Event with QP payload. */ 732 struct vmci_event_qp { 733 struct vmci_event_msg msg; 734 struct vmci_event_payld_qp payload; 735 }; 736 737 /* 738 * Structs used for queue_pair alloc and detach messages. We align fields of 739 * these structs to 64bit boundaries. 740 */ 741 struct vmci_qp_alloc_msg { 742 struct vmci_datagram hdr; 743 struct vmci_handle handle; 744 u32 peer; 745 u32 flags; 746 u64 produce_size; 747 u64 consume_size; 748 u64 num_ppns; 749 750 /* List of PPNs placed here. */ 751 }; 752 753 struct vmci_qp_detach_msg { 754 struct vmci_datagram hdr; 755 struct vmci_handle handle; 756 }; 757 758 /* VMCI Doorbell API. */ 759 #define VMCI_FLAG_DELAYED_CB BIT(0) 760 761 typedef void (*vmci_callback) (void *client_data); 762 763 /* 764 * struct vmci_qp - A vmw_vmci queue pair handle. 765 * 766 * This structure is used as a handle to a queue pair created by 767 * VMCI. It is intentionally left opaque to clients. 768 */ 769 struct vmci_qp; 770 771 /* Callback needed for correctly waiting on events. */ 772 typedef int (*vmci_datagram_recv_cb) (void *client_data, 773 struct vmci_datagram *msg); 774 775 /* VMCI Event API. */ 776 typedef void (*vmci_event_cb) (u32 sub_id, const struct vmci_event_data *ed, 777 void *client_data); 778 779 /* 780 * We use the following inline function to access the payload data 781 * associated with an event data. 782 */ 783 static inline const void * 784 vmci_event_data_const_payload(const struct vmci_event_data *ev_data) 785 { 786 return (const char *)ev_data + sizeof(*ev_data); 787 } 788 789 static inline void *vmci_event_data_payload(struct vmci_event_data *ev_data) 790 { 791 return (void *)vmci_event_data_const_payload(ev_data); 792 } 793 794 /* 795 * Helper to read a value from a head or tail pointer. For X86_32, the 796 * pointer is treated as a 32bit value, since the pointer value 797 * never exceeds a 32bit value in this case. Also, doing an 798 * atomic64_read on X86_32 uniprocessor systems may be implemented 799 * as a non locked cmpxchg8b, that may end up overwriting updates done 800 * by the VMCI device to the memory location. On 32bit SMP, the lock 801 * prefix will be used, so correctness isn't an issue, but using a 802 * 64bit operation still adds unnecessary overhead. 803 */ 804 static inline u64 vmci_q_read_pointer(u64 *var) 805 { 806 return READ_ONCE(*(unsigned long *)var); 807 } 808 809 /* 810 * Helper to set the value of a head or tail pointer. For X86_32, the 811 * pointer is treated as a 32bit value, since the pointer value 812 * never exceeds a 32bit value in this case. On 32bit SMP, using a 813 * locked cmpxchg8b adds unnecessary overhead. 814 */ 815 static inline void vmci_q_set_pointer(u64 *var, u64 new_val) 816 { 817 /* XXX buggered on big-endian */ 818 WRITE_ONCE(*(unsigned long *)var, (unsigned long)new_val); 819 } 820 821 /* 822 * Helper to add a given offset to a head or tail pointer. Wraps the 823 * value of the pointer around the max size of the queue. 824 */ 825 static inline void vmci_qp_add_pointer(u64 *var, size_t add, u64 size) 826 { 827 u64 new_val = vmci_q_read_pointer(var); 828 829 if (new_val >= size - add) 830 new_val -= size; 831 832 new_val += add; 833 834 vmci_q_set_pointer(var, new_val); 835 } 836 837 /* 838 * Helper routine to get the Producer Tail from the supplied queue. 839 */ 840 static inline u64 841 vmci_q_header_producer_tail(const struct vmci_queue_header *q_header) 842 { 843 struct vmci_queue_header *qh = (struct vmci_queue_header *)q_header; 844 return vmci_q_read_pointer(&qh->producer_tail); 845 } 846 847 /* 848 * Helper routine to get the Consumer Head from the supplied queue. 849 */ 850 static inline u64 851 vmci_q_header_consumer_head(const struct vmci_queue_header *q_header) 852 { 853 struct vmci_queue_header *qh = (struct vmci_queue_header *)q_header; 854 return vmci_q_read_pointer(&qh->consumer_head); 855 } 856 857 /* 858 * Helper routine to increment the Producer Tail. Fundamentally, 859 * vmci_qp_add_pointer() is used to manipulate the tail itself. 860 */ 861 static inline void 862 vmci_q_header_add_producer_tail(struct vmci_queue_header *q_header, 863 size_t add, 864 u64 queue_size) 865 { 866 vmci_qp_add_pointer(&q_header->producer_tail, add, queue_size); 867 } 868 869 /* 870 * Helper routine to increment the Consumer Head. Fundamentally, 871 * vmci_qp_add_pointer() is used to manipulate the head itself. 872 */ 873 static inline void 874 vmci_q_header_add_consumer_head(struct vmci_queue_header *q_header, 875 size_t add, 876 u64 queue_size) 877 { 878 vmci_qp_add_pointer(&q_header->consumer_head, add, queue_size); 879 } 880 881 /* 882 * Helper routine for getting the head and the tail pointer for a queue. 883 * Both the VMCIQueues are needed to get both the pointers for one queue. 884 */ 885 static inline void 886 vmci_q_header_get_pointers(const struct vmci_queue_header *produce_q_header, 887 const struct vmci_queue_header *consume_q_header, 888 u64 *producer_tail, 889 u64 *consumer_head) 890 { 891 if (producer_tail) 892 *producer_tail = vmci_q_header_producer_tail(produce_q_header); 893 894 if (consumer_head) 895 *consumer_head = vmci_q_header_consumer_head(consume_q_header); 896 } 897 898 static inline void vmci_q_header_init(struct vmci_queue_header *q_header, 899 const struct vmci_handle handle) 900 { 901 q_header->handle = handle; 902 q_header->producer_tail = 0; 903 q_header->consumer_head = 0; 904 } 905 906 /* 907 * Finds available free space in a produce queue to enqueue more 908 * data or reports an error if queue pair corruption is detected. 909 */ 910 static s64 911 vmci_q_header_free_space(const struct vmci_queue_header *produce_q_header, 912 const struct vmci_queue_header *consume_q_header, 913 const u64 produce_q_size) 914 { 915 u64 tail; 916 u64 head; 917 u64 free_space; 918 919 tail = vmci_q_header_producer_tail(produce_q_header); 920 head = vmci_q_header_consumer_head(consume_q_header); 921 922 if (tail >= produce_q_size || head >= produce_q_size) 923 return VMCI_ERROR_INVALID_SIZE; 924 925 /* 926 * Deduct 1 to avoid tail becoming equal to head which causes 927 * ambiguity. If head and tail are equal it means that the 928 * queue is empty. 929 */ 930 if (tail >= head) 931 free_space = produce_q_size - (tail - head) - 1; 932 else 933 free_space = head - tail - 1; 934 935 return free_space; 936 } 937 938 /* 939 * vmci_q_header_free_space() does all the heavy lifting of 940 * determing the number of free bytes in a Queue. This routine, 941 * then subtracts that size from the full size of the Queue so 942 * the caller knows how many bytes are ready to be dequeued. 943 * Results: 944 * On success, available data size in bytes (up to MAX_INT64). 945 * On failure, appropriate error code. 946 */ 947 static inline s64 948 vmci_q_header_buf_ready(const struct vmci_queue_header *consume_q_header, 949 const struct vmci_queue_header *produce_q_header, 950 const u64 consume_q_size) 951 { 952 s64 free_space; 953 954 free_space = vmci_q_header_free_space(consume_q_header, 955 produce_q_header, consume_q_size); 956 if (free_space < VMCI_SUCCESS) 957 return free_space; 958 959 return consume_q_size - free_space - 1; 960 } 961 962 963 #endif /* _VMW_VMCI_DEF_H_ */ 964