George Zhang | 28d6692 | 2013-01-08 15:52:59 -0800 | [diff] [blame] | 1 | /* |
| 2 | * VMware VMCI Driver |
| 3 | * |
| 4 | * Copyright (C) 2012 VMware, Inc. All rights reserved. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License as published by the |
| 8 | * Free Software Foundation version 2 and no later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, but |
| 11 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| 12 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 13 | * for more details. |
| 14 | */ |
| 15 | |
| 16 | #include <linux/vmw_vmci_defs.h> |
| 17 | #include <linux/vmw_vmci_api.h> |
| 18 | #include <linux/highmem.h> |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/sched.h> |
| 22 | #include <linux/slab.h> |
| 23 | |
| 24 | #include "vmci_queue_pair.h" |
| 25 | #include "vmci_datagram.h" |
| 26 | #include "vmci_doorbell.h" |
| 27 | #include "vmci_context.h" |
| 28 | #include "vmci_driver.h" |
| 29 | #include "vmci_event.h" |
| 30 | |
| 31 | /* |
| 32 | * List of current VMCI contexts. Contexts can be added by |
| 33 | * vmci_ctx_create() and removed via vmci_ctx_destroy(). |
| 34 | * These, along with context lookup, are protected by the |
| 35 | * list structure's lock. |
| 36 | */ |
| 37 | static struct { |
| 38 | struct list_head head; |
| 39 | spinlock_t lock; /* Spinlock for context list operations */ |
| 40 | } ctx_list = { |
| 41 | .head = LIST_HEAD_INIT(ctx_list.head), |
| 42 | .lock = __SPIN_LOCK_UNLOCKED(ctx_list.lock), |
| 43 | }; |
| 44 | |
| 45 | /* Used by contexts that did not set up notify flag pointers */ |
| 46 | static bool ctx_dummy_notify; |
| 47 | |
| 48 | static void ctx_signal_notify(struct vmci_ctx *context) |
| 49 | { |
| 50 | *context->notify = true; |
| 51 | } |
| 52 | |
| 53 | static void ctx_clear_notify(struct vmci_ctx *context) |
| 54 | { |
| 55 | *context->notify = false; |
| 56 | } |
| 57 | |
| 58 | /* |
| 59 | * If nothing requires the attention of the guest, clears both |
| 60 | * notify flag and call. |
| 61 | */ |
| 62 | static void ctx_clear_notify_call(struct vmci_ctx *context) |
| 63 | { |
| 64 | if (context->pending_datagrams == 0 && |
| 65 | vmci_handle_arr_get_size(context->pending_doorbell_array) == 0) |
| 66 | ctx_clear_notify(context); |
| 67 | } |
| 68 | |
| 69 | /* |
| 70 | * Sets the context's notify flag iff datagrams are pending for this |
| 71 | * context. Called from vmci_setup_notify(). |
| 72 | */ |
| 73 | void vmci_ctx_check_signal_notify(struct vmci_ctx *context) |
| 74 | { |
| 75 | spin_lock(&context->lock); |
| 76 | if (context->pending_datagrams) |
| 77 | ctx_signal_notify(context); |
| 78 | spin_unlock(&context->lock); |
| 79 | } |
| 80 | |
| 81 | /* |
| 82 | * Allocates and initializes a VMCI context. |
| 83 | */ |
| 84 | struct vmci_ctx *vmci_ctx_create(u32 cid, u32 priv_flags, |
| 85 | uintptr_t event_hnd, |
| 86 | int user_version, |
| 87 | const struct cred *cred) |
| 88 | { |
| 89 | struct vmci_ctx *context; |
| 90 | int error; |
| 91 | |
| 92 | if (cid == VMCI_INVALID_ID) { |
| 93 | pr_devel("Invalid context ID for VMCI context\n"); |
| 94 | error = -EINVAL; |
| 95 | goto err_out; |
| 96 | } |
| 97 | |
| 98 | if (priv_flags & ~VMCI_PRIVILEGE_ALL_FLAGS) { |
| 99 | pr_devel("Invalid flag (flags=0x%x) for VMCI context\n", |
| 100 | priv_flags); |
| 101 | error = -EINVAL; |
| 102 | goto err_out; |
| 103 | } |
| 104 | |
| 105 | if (user_version == 0) { |
| 106 | pr_devel("Invalid suer_version %d\n", user_version); |
| 107 | error = -EINVAL; |
| 108 | goto err_out; |
| 109 | } |
| 110 | |
| 111 | context = kzalloc(sizeof(*context), GFP_KERNEL); |
| 112 | if (!context) { |
| 113 | pr_warn("Failed to allocate memory for VMCI context\n"); |
| 114 | error = -EINVAL; |
| 115 | goto err_out; |
| 116 | } |
| 117 | |
| 118 | kref_init(&context->kref); |
| 119 | spin_lock_init(&context->lock); |
| 120 | INIT_LIST_HEAD(&context->list_item); |
| 121 | INIT_LIST_HEAD(&context->datagram_queue); |
| 122 | INIT_LIST_HEAD(&context->notifier_list); |
| 123 | |
| 124 | /* Initialize host-specific VMCI context. */ |
| 125 | init_waitqueue_head(&context->host_context.wait_queue); |
| 126 | |
| 127 | context->queue_pair_array = vmci_handle_arr_create(0); |
| 128 | if (!context->queue_pair_array) { |
| 129 | error = -ENOMEM; |
| 130 | goto err_free_ctx; |
| 131 | } |
| 132 | |
| 133 | context->doorbell_array = vmci_handle_arr_create(0); |
| 134 | if (!context->doorbell_array) { |
| 135 | error = -ENOMEM; |
| 136 | goto err_free_qp_array; |
| 137 | } |
| 138 | |
| 139 | context->pending_doorbell_array = vmci_handle_arr_create(0); |
| 140 | if (!context->pending_doorbell_array) { |
| 141 | error = -ENOMEM; |
| 142 | goto err_free_db_array; |
| 143 | } |
| 144 | |
| 145 | context->user_version = user_version; |
| 146 | |
| 147 | context->priv_flags = priv_flags; |
| 148 | |
| 149 | if (cred) |
| 150 | context->cred = get_cred(cred); |
| 151 | |
| 152 | context->notify = &ctx_dummy_notify; |
| 153 | context->notify_page = NULL; |
| 154 | |
| 155 | /* |
| 156 | * If we collide with an existing context we generate a new |
| 157 | * and use it instead. The VMX will determine if regeneration |
| 158 | * is okay. Since there isn't 4B - 16 VMs running on a given |
| 159 | * host, the below loop will terminate. |
| 160 | */ |
| 161 | spin_lock(&ctx_list.lock); |
| 162 | |
| 163 | while (vmci_ctx_exists(cid)) { |
| 164 | /* We reserve the lowest 16 ids for fixed contexts. */ |
| 165 | cid = max(cid, VMCI_RESERVED_CID_LIMIT - 1) + 1; |
| 166 | if (cid == VMCI_INVALID_ID) |
| 167 | cid = VMCI_RESERVED_CID_LIMIT; |
| 168 | } |
| 169 | context->cid = cid; |
| 170 | |
| 171 | list_add_tail_rcu(&context->list_item, &ctx_list.head); |
| 172 | spin_unlock(&ctx_list.lock); |
| 173 | |
| 174 | return context; |
| 175 | |
| 176 | err_free_db_array: |
| 177 | vmci_handle_arr_destroy(context->doorbell_array); |
| 178 | err_free_qp_array: |
| 179 | vmci_handle_arr_destroy(context->queue_pair_array); |
| 180 | err_free_ctx: |
| 181 | kfree(context); |
| 182 | err_out: |
| 183 | return ERR_PTR(error); |
| 184 | } |
| 185 | |
| 186 | /* |
| 187 | * Destroy VMCI context. |
| 188 | */ |
| 189 | void vmci_ctx_destroy(struct vmci_ctx *context) |
| 190 | { |
| 191 | spin_lock(&ctx_list.lock); |
| 192 | list_del_rcu(&context->list_item); |
| 193 | spin_unlock(&ctx_list.lock); |
| 194 | synchronize_rcu(); |
| 195 | |
| 196 | vmci_ctx_put(context); |
| 197 | } |
| 198 | |
| 199 | /* |
| 200 | * Fire notification for all contexts interested in given cid. |
| 201 | */ |
| 202 | static int ctx_fire_notification(u32 context_id, u32 priv_flags) |
| 203 | { |
| 204 | u32 i, array_size; |
| 205 | struct vmci_ctx *sub_ctx; |
| 206 | struct vmci_handle_arr *subscriber_array; |
| 207 | struct vmci_handle context_handle = |
| 208 | vmci_make_handle(context_id, VMCI_EVENT_HANDLER); |
| 209 | |
| 210 | /* |
| 211 | * We create an array to hold the subscribers we find when |
| 212 | * scanning through all contexts. |
| 213 | */ |
| 214 | subscriber_array = vmci_handle_arr_create(0); |
| 215 | if (subscriber_array == NULL) |
| 216 | return VMCI_ERROR_NO_MEM; |
| 217 | |
| 218 | /* |
| 219 | * Scan all contexts to find who is interested in being |
| 220 | * notified about given contextID. |
| 221 | */ |
| 222 | rcu_read_lock(); |
| 223 | list_for_each_entry_rcu(sub_ctx, &ctx_list.head, list_item) { |
| 224 | struct vmci_handle_list *node; |
| 225 | |
| 226 | /* |
| 227 | * We only deliver notifications of the removal of |
| 228 | * contexts, if the two contexts are allowed to |
| 229 | * interact. |
| 230 | */ |
| 231 | if (vmci_deny_interaction(priv_flags, sub_ctx->priv_flags)) |
| 232 | continue; |
| 233 | |
| 234 | list_for_each_entry_rcu(node, &sub_ctx->notifier_list, node) { |
| 235 | if (!vmci_handle_is_equal(node->handle, context_handle)) |
| 236 | continue; |
| 237 | |
| 238 | vmci_handle_arr_append_entry(&subscriber_array, |
| 239 | vmci_make_handle(sub_ctx->cid, |
| 240 | VMCI_EVENT_HANDLER)); |
| 241 | } |
| 242 | } |
| 243 | rcu_read_unlock(); |
| 244 | |
| 245 | /* Fire event to all subscribers. */ |
| 246 | array_size = vmci_handle_arr_get_size(subscriber_array); |
| 247 | for (i = 0; i < array_size; i++) { |
| 248 | int result; |
| 249 | struct vmci_event_ctx ev; |
| 250 | |
| 251 | ev.msg.hdr.dst = vmci_handle_arr_get_entry(subscriber_array, i); |
| 252 | ev.msg.hdr.src = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID, |
| 253 | VMCI_CONTEXT_RESOURCE_ID); |
| 254 | ev.msg.hdr.payload_size = sizeof(ev) - sizeof(ev.msg.hdr); |
| 255 | ev.msg.event_data.event = VMCI_EVENT_CTX_REMOVED; |
| 256 | ev.payload.context_id = context_id; |
| 257 | |
| 258 | result = vmci_datagram_dispatch(VMCI_HYPERVISOR_CONTEXT_ID, |
| 259 | &ev.msg.hdr, false); |
| 260 | if (result < VMCI_SUCCESS) { |
| 261 | pr_devel("Failed to enqueue event datagram (type=%d) for context (ID=0x%x)\n", |
| 262 | ev.msg.event_data.event, |
| 263 | ev.msg.hdr.dst.context); |
| 264 | /* We continue to enqueue on next subscriber. */ |
| 265 | } |
| 266 | } |
| 267 | vmci_handle_arr_destroy(subscriber_array); |
| 268 | |
| 269 | return VMCI_SUCCESS; |
| 270 | } |
| 271 | |
| 272 | /* |
| 273 | * Returns the current number of pending datagrams. The call may |
| 274 | * also serve as a synchronization point for the datagram queue, |
| 275 | * as no enqueue operations can occur concurrently. |
| 276 | */ |
| 277 | int vmci_ctx_pending_datagrams(u32 cid, u32 *pending) |
| 278 | { |
| 279 | struct vmci_ctx *context; |
| 280 | |
| 281 | context = vmci_ctx_get(cid); |
| 282 | if (context == NULL) |
| 283 | return VMCI_ERROR_INVALID_ARGS; |
| 284 | |
| 285 | spin_lock(&context->lock); |
| 286 | if (pending) |
| 287 | *pending = context->pending_datagrams; |
| 288 | spin_unlock(&context->lock); |
| 289 | vmci_ctx_put(context); |
| 290 | |
| 291 | return VMCI_SUCCESS; |
| 292 | } |
| 293 | |
| 294 | /* |
| 295 | * Queues a VMCI datagram for the appropriate target VM context. |
| 296 | */ |
| 297 | int vmci_ctx_enqueue_datagram(u32 cid, struct vmci_datagram *dg) |
| 298 | { |
| 299 | struct vmci_datagram_queue_entry *dq_entry; |
| 300 | struct vmci_ctx *context; |
| 301 | struct vmci_handle dg_src; |
| 302 | size_t vmci_dg_size; |
| 303 | |
| 304 | vmci_dg_size = VMCI_DG_SIZE(dg); |
| 305 | if (vmci_dg_size > VMCI_MAX_DG_SIZE) { |
| 306 | pr_devel("Datagram too large (bytes=%Zu)\n", vmci_dg_size); |
| 307 | return VMCI_ERROR_INVALID_ARGS; |
| 308 | } |
| 309 | |
| 310 | /* Get the target VM's VMCI context. */ |
| 311 | context = vmci_ctx_get(cid); |
| 312 | if (!context) { |
| 313 | pr_devel("Invalid context (ID=0x%x)\n", cid); |
| 314 | return VMCI_ERROR_INVALID_ARGS; |
| 315 | } |
| 316 | |
| 317 | /* Allocate guest call entry and add it to the target VM's queue. */ |
| 318 | dq_entry = kmalloc(sizeof(*dq_entry), GFP_KERNEL); |
| 319 | if (dq_entry == NULL) { |
| 320 | pr_warn("Failed to allocate memory for datagram\n"); |
| 321 | vmci_ctx_put(context); |
| 322 | return VMCI_ERROR_NO_MEM; |
| 323 | } |
| 324 | dq_entry->dg = dg; |
| 325 | dq_entry->dg_size = vmci_dg_size; |
| 326 | dg_src = dg->src; |
| 327 | INIT_LIST_HEAD(&dq_entry->list_item); |
| 328 | |
| 329 | spin_lock(&context->lock); |
| 330 | |
| 331 | /* |
| 332 | * We put a higher limit on datagrams from the hypervisor. If |
| 333 | * the pending datagram is not from hypervisor, then we check |
| 334 | * if enqueueing it would exceed the |
| 335 | * VMCI_MAX_DATAGRAM_QUEUE_SIZE limit on the destination. If |
| 336 | * the pending datagram is from hypervisor, we allow it to be |
| 337 | * queued at the destination side provided we don't reach the |
| 338 | * VMCI_MAX_DATAGRAM_AND_EVENT_QUEUE_SIZE limit. |
| 339 | */ |
| 340 | if (context->datagram_queue_size + vmci_dg_size >= |
| 341 | VMCI_MAX_DATAGRAM_QUEUE_SIZE && |
| 342 | (!vmci_handle_is_equal(dg_src, |
| 343 | vmci_make_handle |
| 344 | (VMCI_HYPERVISOR_CONTEXT_ID, |
| 345 | VMCI_CONTEXT_RESOURCE_ID)) || |
| 346 | context->datagram_queue_size + vmci_dg_size >= |
| 347 | VMCI_MAX_DATAGRAM_AND_EVENT_QUEUE_SIZE)) { |
| 348 | spin_unlock(&context->lock); |
| 349 | vmci_ctx_put(context); |
| 350 | kfree(dq_entry); |
| 351 | pr_devel("Context (ID=0x%x) receive queue is full\n", cid); |
| 352 | return VMCI_ERROR_NO_RESOURCES; |
| 353 | } |
| 354 | |
| 355 | list_add(&dq_entry->list_item, &context->datagram_queue); |
| 356 | context->pending_datagrams++; |
| 357 | context->datagram_queue_size += vmci_dg_size; |
| 358 | ctx_signal_notify(context); |
| 359 | wake_up(&context->host_context.wait_queue); |
| 360 | spin_unlock(&context->lock); |
| 361 | vmci_ctx_put(context); |
| 362 | |
| 363 | return vmci_dg_size; |
| 364 | } |
| 365 | |
| 366 | /* |
| 367 | * Verifies whether a context with the specified context ID exists. |
| 368 | * FIXME: utility is dubious as no decisions can be reliably made |
| 369 | * using this data as context can appear and disappear at any time. |
| 370 | */ |
| 371 | bool vmci_ctx_exists(u32 cid) |
| 372 | { |
| 373 | struct vmci_ctx *context; |
| 374 | bool exists = false; |
| 375 | |
| 376 | rcu_read_lock(); |
| 377 | |
| 378 | list_for_each_entry_rcu(context, &ctx_list.head, list_item) { |
| 379 | if (context->cid == cid) { |
| 380 | exists = true; |
| 381 | break; |
| 382 | } |
| 383 | } |
| 384 | |
| 385 | rcu_read_unlock(); |
| 386 | return exists; |
| 387 | } |
| 388 | |
| 389 | /* |
| 390 | * Retrieves VMCI context corresponding to the given cid. |
| 391 | */ |
| 392 | struct vmci_ctx *vmci_ctx_get(u32 cid) |
| 393 | { |
| 394 | struct vmci_ctx *c, *context = NULL; |
| 395 | |
| 396 | if (cid == VMCI_INVALID_ID) |
| 397 | return NULL; |
| 398 | |
| 399 | rcu_read_lock(); |
| 400 | list_for_each_entry_rcu(c, &ctx_list.head, list_item) { |
| 401 | if (c->cid == cid) { |
| 402 | /* |
| 403 | * The context owner drops its own reference to the |
| 404 | * context only after removing it from the list and |
| 405 | * waiting for RCU grace period to expire. This |
| 406 | * means that we are not about to increase the |
| 407 | * reference count of something that is in the |
| 408 | * process of being destroyed. |
| 409 | */ |
| 410 | context = c; |
| 411 | kref_get(&context->kref); |
| 412 | break; |
| 413 | } |
| 414 | } |
| 415 | rcu_read_unlock(); |
| 416 | |
| 417 | return context; |
| 418 | } |
| 419 | |
| 420 | /* |
| 421 | * Deallocates all parts of a context data structure. This |
| 422 | * function doesn't lock the context, because it assumes that |
| 423 | * the caller was holding the last reference to context. |
| 424 | */ |
| 425 | static void ctx_free_ctx(struct kref *kref) |
| 426 | { |
| 427 | struct vmci_ctx *context = container_of(kref, struct vmci_ctx, kref); |
| 428 | struct vmci_datagram_queue_entry *dq_entry, *dq_entry_tmp; |
| 429 | struct vmci_handle temp_handle; |
| 430 | struct vmci_handle_list *notifier, *tmp; |
| 431 | |
| 432 | /* |
| 433 | * Fire event to all contexts interested in knowing this |
| 434 | * context is dying. |
| 435 | */ |
| 436 | ctx_fire_notification(context->cid, context->priv_flags); |
| 437 | |
| 438 | /* |
| 439 | * Cleanup all queue pair resources attached to context. If |
| 440 | * the VM dies without cleaning up, this code will make sure |
| 441 | * that no resources are leaked. |
| 442 | */ |
| 443 | temp_handle = vmci_handle_arr_get_entry(context->queue_pair_array, 0); |
| 444 | while (!vmci_handle_is_equal(temp_handle, VMCI_INVALID_HANDLE)) { |
| 445 | if (vmci_qp_broker_detach(temp_handle, |
| 446 | context) < VMCI_SUCCESS) { |
| 447 | /* |
| 448 | * When vmci_qp_broker_detach() succeeds it |
| 449 | * removes the handle from the array. If |
| 450 | * detach fails, we must remove the handle |
| 451 | * ourselves. |
| 452 | */ |
| 453 | vmci_handle_arr_remove_entry(context->queue_pair_array, |
| 454 | temp_handle); |
| 455 | } |
| 456 | temp_handle = |
| 457 | vmci_handle_arr_get_entry(context->queue_pair_array, 0); |
| 458 | } |
| 459 | |
| 460 | /* |
| 461 | * It is fine to destroy this without locking the callQueue, as |
| 462 | * this is the only thread having a reference to the context. |
| 463 | */ |
| 464 | list_for_each_entry_safe(dq_entry, dq_entry_tmp, |
| 465 | &context->datagram_queue, list_item) { |
| 466 | WARN_ON(dq_entry->dg_size != VMCI_DG_SIZE(dq_entry->dg)); |
| 467 | list_del(&dq_entry->list_item); |
| 468 | kfree(dq_entry->dg); |
| 469 | kfree(dq_entry); |
| 470 | } |
| 471 | |
| 472 | list_for_each_entry_safe(notifier, tmp, |
| 473 | &context->notifier_list, node) { |
| 474 | list_del(¬ifier->node); |
| 475 | kfree(notifier); |
| 476 | } |
| 477 | |
| 478 | vmci_handle_arr_destroy(context->queue_pair_array); |
| 479 | vmci_handle_arr_destroy(context->doorbell_array); |
| 480 | vmci_handle_arr_destroy(context->pending_doorbell_array); |
| 481 | vmci_ctx_unset_notify(context); |
| 482 | if (context->cred) |
| 483 | put_cred(context->cred); |
| 484 | kfree(context); |
| 485 | } |
| 486 | |
| 487 | /* |
| 488 | * Drops reference to VMCI context. If this is the last reference to |
| 489 | * the context it will be deallocated. A context is created with |
| 490 | * a reference count of one, and on destroy, it is removed from |
| 491 | * the context list before its reference count is decremented. Thus, |
| 492 | * if we reach zero, we are sure that nobody else are about to increment |
| 493 | * it (they need the entry in the context list for that), and so there |
| 494 | * is no need for locking. |
| 495 | */ |
| 496 | void vmci_ctx_put(struct vmci_ctx *context) |
| 497 | { |
| 498 | kref_put(&context->kref, ctx_free_ctx); |
| 499 | } |
| 500 | |
| 501 | /* |
| 502 | * Dequeues the next datagram and returns it to caller. |
| 503 | * The caller passes in a pointer to the max size datagram |
| 504 | * it can handle and the datagram is only unqueued if the |
| 505 | * size is less than max_size. If larger max_size is set to |
| 506 | * the size of the datagram to give the caller a chance to |
| 507 | * set up a larger buffer for the guestcall. |
| 508 | */ |
| 509 | int vmci_ctx_dequeue_datagram(struct vmci_ctx *context, |
| 510 | size_t *max_size, |
| 511 | struct vmci_datagram **dg) |
| 512 | { |
| 513 | struct vmci_datagram_queue_entry *dq_entry; |
| 514 | struct list_head *list_item; |
| 515 | int rv; |
| 516 | |
| 517 | /* Dequeue the next datagram entry. */ |
| 518 | spin_lock(&context->lock); |
| 519 | if (context->pending_datagrams == 0) { |
| 520 | ctx_clear_notify_call(context); |
| 521 | spin_unlock(&context->lock); |
| 522 | pr_devel("No datagrams pending\n"); |
| 523 | return VMCI_ERROR_NO_MORE_DATAGRAMS; |
| 524 | } |
| 525 | |
| 526 | list_item = context->datagram_queue.next; |
| 527 | |
| 528 | dq_entry = |
| 529 | list_entry(list_item, struct vmci_datagram_queue_entry, list_item); |
| 530 | |
| 531 | /* Check size of caller's buffer. */ |
| 532 | if (*max_size < dq_entry->dg_size) { |
| 533 | *max_size = dq_entry->dg_size; |
| 534 | spin_unlock(&context->lock); |
| 535 | pr_devel("Caller's buffer should be at least (size=%u bytes)\n", |
| 536 | (u32) *max_size); |
| 537 | return VMCI_ERROR_NO_MEM; |
| 538 | } |
| 539 | |
| 540 | list_del(list_item); |
| 541 | context->pending_datagrams--; |
| 542 | context->datagram_queue_size -= dq_entry->dg_size; |
| 543 | if (context->pending_datagrams == 0) { |
| 544 | ctx_clear_notify_call(context); |
| 545 | rv = VMCI_SUCCESS; |
| 546 | } else { |
| 547 | /* |
| 548 | * Return the size of the next datagram. |
| 549 | */ |
| 550 | struct vmci_datagram_queue_entry *next_entry; |
| 551 | |
| 552 | list_item = context->datagram_queue.next; |
| 553 | next_entry = |
| 554 | list_entry(list_item, struct vmci_datagram_queue_entry, |
| 555 | list_item); |
| 556 | |
| 557 | /* |
| 558 | * The following size_t -> int truncation is fine as |
| 559 | * the maximum size of a (routable) datagram is 68KB. |
| 560 | */ |
| 561 | rv = (int)next_entry->dg_size; |
| 562 | } |
| 563 | spin_unlock(&context->lock); |
| 564 | |
| 565 | /* Caller must free datagram. */ |
| 566 | *dg = dq_entry->dg; |
| 567 | dq_entry->dg = NULL; |
| 568 | kfree(dq_entry); |
| 569 | |
| 570 | return rv; |
| 571 | } |
| 572 | |
| 573 | /* |
| 574 | * Reverts actions set up by vmci_setup_notify(). Unmaps and unlocks the |
| 575 | * page mapped/locked by vmci_setup_notify(). |
| 576 | */ |
| 577 | void vmci_ctx_unset_notify(struct vmci_ctx *context) |
| 578 | { |
| 579 | struct page *notify_page; |
| 580 | |
| 581 | spin_lock(&context->lock); |
| 582 | |
| 583 | notify_page = context->notify_page; |
| 584 | context->notify = &ctx_dummy_notify; |
| 585 | context->notify_page = NULL; |
| 586 | |
| 587 | spin_unlock(&context->lock); |
| 588 | |
| 589 | if (notify_page) { |
| 590 | kunmap(notify_page); |
| 591 | put_page(notify_page); |
| 592 | } |
| 593 | } |
| 594 | |
| 595 | /* |
| 596 | * Add remote_cid to list of contexts current contexts wants |
| 597 | * notifications from/about. |
| 598 | */ |
| 599 | int vmci_ctx_add_notification(u32 context_id, u32 remote_cid) |
| 600 | { |
| 601 | struct vmci_ctx *context; |
| 602 | struct vmci_handle_list *notifier, *n; |
| 603 | int result; |
| 604 | bool exists = false; |
| 605 | |
| 606 | context = vmci_ctx_get(context_id); |
| 607 | if (!context) |
| 608 | return VMCI_ERROR_NOT_FOUND; |
| 609 | |
| 610 | if (VMCI_CONTEXT_IS_VM(context_id) && VMCI_CONTEXT_IS_VM(remote_cid)) { |
| 611 | pr_devel("Context removed notifications for other VMs not supported (src=0x%x, remote=0x%x)\n", |
| 612 | context_id, remote_cid); |
| 613 | result = VMCI_ERROR_DST_UNREACHABLE; |
| 614 | goto out; |
| 615 | } |
| 616 | |
| 617 | if (context->priv_flags & VMCI_PRIVILEGE_FLAG_RESTRICTED) { |
| 618 | result = VMCI_ERROR_NO_ACCESS; |
| 619 | goto out; |
| 620 | } |
| 621 | |
| 622 | notifier = kmalloc(sizeof(struct vmci_handle_list), GFP_KERNEL); |
| 623 | if (!notifier) { |
| 624 | result = VMCI_ERROR_NO_MEM; |
| 625 | goto out; |
| 626 | } |
| 627 | |
| 628 | INIT_LIST_HEAD(¬ifier->node); |
| 629 | notifier->handle = vmci_make_handle(remote_cid, VMCI_EVENT_HANDLER); |
| 630 | |
| 631 | spin_lock(&context->lock); |
| 632 | |
| 633 | list_for_each_entry(n, &context->notifier_list, node) { |
| 634 | if (vmci_handle_is_equal(n->handle, notifier->handle)) { |
| 635 | exists = true; |
| 636 | break; |
| 637 | } |
| 638 | } |
| 639 | |
| 640 | if (exists) { |
| 641 | kfree(notifier); |
| 642 | result = VMCI_ERROR_ALREADY_EXISTS; |
| 643 | } else { |
| 644 | list_add_tail_rcu(¬ifier->node, &context->notifier_list); |
| 645 | context->n_notifiers++; |
| 646 | result = VMCI_SUCCESS; |
| 647 | } |
| 648 | |
| 649 | spin_unlock(&context->lock); |
| 650 | |
| 651 | out: |
| 652 | vmci_ctx_put(context); |
| 653 | return result; |
| 654 | } |
| 655 | |
| 656 | /* |
| 657 | * Remove remote_cid from current context's list of contexts it is |
| 658 | * interested in getting notifications from/about. |
| 659 | */ |
| 660 | int vmci_ctx_remove_notification(u32 context_id, u32 remote_cid) |
| 661 | { |
| 662 | struct vmci_ctx *context; |
| 663 | struct vmci_handle_list *notifier, *tmp; |
| 664 | struct vmci_handle handle; |
| 665 | bool found = false; |
| 666 | |
| 667 | context = vmci_ctx_get(context_id); |
| 668 | if (!context) |
| 669 | return VMCI_ERROR_NOT_FOUND; |
| 670 | |
| 671 | handle = vmci_make_handle(remote_cid, VMCI_EVENT_HANDLER); |
| 672 | |
| 673 | spin_lock(&context->lock); |
| 674 | list_for_each_entry_safe(notifier, tmp, |
| 675 | &context->notifier_list, node) { |
| 676 | if (vmci_handle_is_equal(notifier->handle, handle)) { |
| 677 | list_del_rcu(¬ifier->node); |
| 678 | context->n_notifiers--; |
| 679 | found = true; |
| 680 | break; |
| 681 | } |
| 682 | } |
| 683 | spin_unlock(&context->lock); |
| 684 | |
| 685 | if (found) { |
| 686 | synchronize_rcu(); |
| 687 | kfree(notifier); |
| 688 | } |
| 689 | |
| 690 | vmci_ctx_put(context); |
| 691 | |
| 692 | return found ? VMCI_SUCCESS : VMCI_ERROR_NOT_FOUND; |
| 693 | } |
| 694 | |
| 695 | static int vmci_ctx_get_chkpt_notifiers(struct vmci_ctx *context, |
| 696 | u32 *buf_size, void **pbuf) |
| 697 | { |
| 698 | u32 *notifiers; |
| 699 | size_t data_size; |
| 700 | struct vmci_handle_list *entry; |
| 701 | int i = 0; |
| 702 | |
| 703 | if (context->n_notifiers == 0) { |
| 704 | *buf_size = 0; |
| 705 | *pbuf = NULL; |
| 706 | return VMCI_SUCCESS; |
| 707 | } |
| 708 | |
| 709 | data_size = context->n_notifiers * sizeof(*notifiers); |
| 710 | if (*buf_size < data_size) { |
| 711 | *buf_size = data_size; |
| 712 | return VMCI_ERROR_MORE_DATA; |
| 713 | } |
| 714 | |
| 715 | notifiers = kmalloc(data_size, GFP_ATOMIC); /* FIXME: want GFP_KERNEL */ |
| 716 | if (!notifiers) |
| 717 | return VMCI_ERROR_NO_MEM; |
| 718 | |
| 719 | list_for_each_entry(entry, &context->notifier_list, node) |
| 720 | notifiers[i++] = entry->handle.context; |
| 721 | |
| 722 | *buf_size = data_size; |
| 723 | *pbuf = notifiers; |
| 724 | return VMCI_SUCCESS; |
| 725 | } |
| 726 | |
| 727 | static int vmci_ctx_get_chkpt_doorbells(struct vmci_ctx *context, |
| 728 | u32 *buf_size, void **pbuf) |
| 729 | { |
| 730 | struct dbell_cpt_state *dbells; |
| 731 | size_t n_doorbells; |
| 732 | int i; |
| 733 | |
| 734 | n_doorbells = vmci_handle_arr_get_size(context->doorbell_array); |
| 735 | if (n_doorbells > 0) { |
| 736 | size_t data_size = n_doorbells * sizeof(*dbells); |
| 737 | if (*buf_size < data_size) { |
| 738 | *buf_size = data_size; |
| 739 | return VMCI_ERROR_MORE_DATA; |
| 740 | } |
| 741 | |
| 742 | dbells = kmalloc(data_size, GFP_ATOMIC); |
| 743 | if (!dbells) |
| 744 | return VMCI_ERROR_NO_MEM; |
| 745 | |
| 746 | for (i = 0; i < n_doorbells; i++) |
| 747 | dbells[i].handle = vmci_handle_arr_get_entry( |
| 748 | context->doorbell_array, i); |
| 749 | |
| 750 | *buf_size = data_size; |
| 751 | *pbuf = dbells; |
| 752 | } else { |
| 753 | *buf_size = 0; |
| 754 | *pbuf = NULL; |
| 755 | } |
| 756 | |
| 757 | return VMCI_SUCCESS; |
| 758 | } |
| 759 | |
| 760 | /* |
| 761 | * Get current context's checkpoint state of given type. |
| 762 | */ |
| 763 | int vmci_ctx_get_chkpt_state(u32 context_id, |
| 764 | u32 cpt_type, |
| 765 | u32 *buf_size, |
| 766 | void **pbuf) |
| 767 | { |
| 768 | struct vmci_ctx *context; |
| 769 | int result; |
| 770 | |
| 771 | context = vmci_ctx_get(context_id); |
| 772 | if (!context) |
| 773 | return VMCI_ERROR_NOT_FOUND; |
| 774 | |
| 775 | spin_lock(&context->lock); |
| 776 | |
| 777 | switch (cpt_type) { |
| 778 | case VMCI_NOTIFICATION_CPT_STATE: |
| 779 | result = vmci_ctx_get_chkpt_notifiers(context, buf_size, pbuf); |
| 780 | break; |
| 781 | |
| 782 | case VMCI_WELLKNOWN_CPT_STATE: |
| 783 | /* |
| 784 | * For compatibility with VMX'en with VM to VM communication, we |
| 785 | * always return zero wellknown handles. |
| 786 | */ |
| 787 | |
| 788 | *buf_size = 0; |
| 789 | *pbuf = NULL; |
| 790 | result = VMCI_SUCCESS; |
| 791 | break; |
| 792 | |
| 793 | case VMCI_DOORBELL_CPT_STATE: |
| 794 | result = vmci_ctx_get_chkpt_doorbells(context, buf_size, pbuf); |
| 795 | break; |
| 796 | |
| 797 | default: |
| 798 | pr_devel("Invalid cpt state (type=%d)\n", cpt_type); |
| 799 | result = VMCI_ERROR_INVALID_ARGS; |
| 800 | break; |
| 801 | } |
| 802 | |
| 803 | spin_unlock(&context->lock); |
| 804 | vmci_ctx_put(context); |
| 805 | |
| 806 | return result; |
| 807 | } |
| 808 | |
| 809 | /* |
| 810 | * Set current context's checkpoint state of given type. |
| 811 | */ |
| 812 | int vmci_ctx_set_chkpt_state(u32 context_id, |
| 813 | u32 cpt_type, |
| 814 | u32 buf_size, |
| 815 | void *cpt_buf) |
| 816 | { |
| 817 | u32 i; |
| 818 | u32 current_id; |
| 819 | int result = VMCI_SUCCESS; |
| 820 | u32 num_ids = buf_size / sizeof(u32); |
| 821 | |
| 822 | if (cpt_type == VMCI_WELLKNOWN_CPT_STATE && num_ids > 0) { |
| 823 | /* |
| 824 | * We would end up here if VMX with VM to VM communication |
| 825 | * attempts to restore a checkpoint with wellknown handles. |
| 826 | */ |
| 827 | pr_warn("Attempt to restore checkpoint with obsolete wellknown handles\n"); |
| 828 | return VMCI_ERROR_OBSOLETE; |
| 829 | } |
| 830 | |
| 831 | if (cpt_type != VMCI_NOTIFICATION_CPT_STATE) { |
| 832 | pr_devel("Invalid cpt state (type=%d)\n", cpt_type); |
| 833 | return VMCI_ERROR_INVALID_ARGS; |
| 834 | } |
| 835 | |
| 836 | for (i = 0; i < num_ids && result == VMCI_SUCCESS; i++) { |
| 837 | current_id = ((u32 *)cpt_buf)[i]; |
| 838 | result = vmci_ctx_add_notification(context_id, current_id); |
| 839 | if (result != VMCI_SUCCESS) |
| 840 | break; |
| 841 | } |
| 842 | if (result != VMCI_SUCCESS) |
| 843 | pr_devel("Failed to set cpt state (type=%d) (error=%d)\n", |
| 844 | cpt_type, result); |
| 845 | |
| 846 | return result; |
| 847 | } |
| 848 | |
| 849 | /* |
| 850 | * Retrieves the specified context's pending notifications in the |
| 851 | * form of a handle array. The handle arrays returned are the |
| 852 | * actual data - not a copy and should not be modified by the |
| 853 | * caller. They must be released using |
| 854 | * vmci_ctx_rcv_notifications_release. |
| 855 | */ |
| 856 | int vmci_ctx_rcv_notifications_get(u32 context_id, |
| 857 | struct vmci_handle_arr **db_handle_array, |
| 858 | struct vmci_handle_arr **qp_handle_array) |
| 859 | { |
| 860 | struct vmci_ctx *context; |
| 861 | int result = VMCI_SUCCESS; |
| 862 | |
| 863 | context = vmci_ctx_get(context_id); |
| 864 | if (context == NULL) |
| 865 | return VMCI_ERROR_NOT_FOUND; |
| 866 | |
| 867 | spin_lock(&context->lock); |
| 868 | |
| 869 | *db_handle_array = context->pending_doorbell_array; |
| 870 | context->pending_doorbell_array = vmci_handle_arr_create(0); |
| 871 | if (!context->pending_doorbell_array) { |
| 872 | context->pending_doorbell_array = *db_handle_array; |
| 873 | *db_handle_array = NULL; |
| 874 | result = VMCI_ERROR_NO_MEM; |
| 875 | } |
| 876 | *qp_handle_array = NULL; |
| 877 | |
| 878 | spin_unlock(&context->lock); |
| 879 | vmci_ctx_put(context); |
| 880 | |
| 881 | return result; |
| 882 | } |
| 883 | |
| 884 | /* |
| 885 | * Releases handle arrays with pending notifications previously |
| 886 | * retrieved using vmci_ctx_rcv_notifications_get. If the |
| 887 | * notifications were not successfully handed over to the guest, |
| 888 | * success must be false. |
| 889 | */ |
| 890 | void vmci_ctx_rcv_notifications_release(u32 context_id, |
| 891 | struct vmci_handle_arr *db_handle_array, |
| 892 | struct vmci_handle_arr *qp_handle_array, |
| 893 | bool success) |
| 894 | { |
| 895 | struct vmci_ctx *context = vmci_ctx_get(context_id); |
| 896 | |
| 897 | spin_lock(&context->lock); |
| 898 | if (!success) { |
| 899 | struct vmci_handle handle; |
| 900 | |
| 901 | /* |
| 902 | * New notifications may have been added while we were not |
| 903 | * holding the context lock, so we transfer any new pending |
| 904 | * doorbell notifications to the old array, and reinstate the |
| 905 | * old array. |
| 906 | */ |
| 907 | |
| 908 | handle = vmci_handle_arr_remove_tail( |
| 909 | context->pending_doorbell_array); |
| 910 | while (!vmci_handle_is_invalid(handle)) { |
| 911 | if (!vmci_handle_arr_has_entry(db_handle_array, |
| 912 | handle)) { |
| 913 | vmci_handle_arr_append_entry( |
| 914 | &db_handle_array, handle); |
| 915 | } |
| 916 | handle = vmci_handle_arr_remove_tail( |
| 917 | context->pending_doorbell_array); |
| 918 | } |
| 919 | vmci_handle_arr_destroy(context->pending_doorbell_array); |
| 920 | context->pending_doorbell_array = db_handle_array; |
| 921 | db_handle_array = NULL; |
| 922 | } else { |
| 923 | ctx_clear_notify_call(context); |
| 924 | } |
| 925 | spin_unlock(&context->lock); |
| 926 | vmci_ctx_put(context); |
| 927 | |
| 928 | if (db_handle_array) |
| 929 | vmci_handle_arr_destroy(db_handle_array); |
| 930 | |
| 931 | if (qp_handle_array) |
| 932 | vmci_handle_arr_destroy(qp_handle_array); |
| 933 | } |
| 934 | |
| 935 | /* |
| 936 | * Registers that a new doorbell handle has been allocated by the |
| 937 | * context. Only doorbell handles registered can be notified. |
| 938 | */ |
| 939 | int vmci_ctx_dbell_create(u32 context_id, struct vmci_handle handle) |
| 940 | { |
| 941 | struct vmci_ctx *context; |
| 942 | int result; |
| 943 | |
| 944 | if (context_id == VMCI_INVALID_ID || vmci_handle_is_invalid(handle)) |
| 945 | return VMCI_ERROR_INVALID_ARGS; |
| 946 | |
| 947 | context = vmci_ctx_get(context_id); |
| 948 | if (context == NULL) |
| 949 | return VMCI_ERROR_NOT_FOUND; |
| 950 | |
| 951 | spin_lock(&context->lock); |
| 952 | if (!vmci_handle_arr_has_entry(context->doorbell_array, handle)) { |
| 953 | vmci_handle_arr_append_entry(&context->doorbell_array, handle); |
| 954 | result = VMCI_SUCCESS; |
| 955 | } else { |
| 956 | result = VMCI_ERROR_DUPLICATE_ENTRY; |
| 957 | } |
| 958 | |
| 959 | spin_unlock(&context->lock); |
| 960 | vmci_ctx_put(context); |
| 961 | |
| 962 | return result; |
| 963 | } |
| 964 | |
| 965 | /* |
| 966 | * Unregisters a doorbell handle that was previously registered |
| 967 | * with vmci_ctx_dbell_create. |
| 968 | */ |
| 969 | int vmci_ctx_dbell_destroy(u32 context_id, struct vmci_handle handle) |
| 970 | { |
| 971 | struct vmci_ctx *context; |
| 972 | struct vmci_handle removed_handle; |
| 973 | |
| 974 | if (context_id == VMCI_INVALID_ID || vmci_handle_is_invalid(handle)) |
| 975 | return VMCI_ERROR_INVALID_ARGS; |
| 976 | |
| 977 | context = vmci_ctx_get(context_id); |
| 978 | if (context == NULL) |
| 979 | return VMCI_ERROR_NOT_FOUND; |
| 980 | |
| 981 | spin_lock(&context->lock); |
| 982 | removed_handle = |
| 983 | vmci_handle_arr_remove_entry(context->doorbell_array, handle); |
| 984 | vmci_handle_arr_remove_entry(context->pending_doorbell_array, handle); |
| 985 | spin_unlock(&context->lock); |
| 986 | |
| 987 | vmci_ctx_put(context); |
| 988 | |
| 989 | return vmci_handle_is_invalid(removed_handle) ? |
| 990 | VMCI_ERROR_NOT_FOUND : VMCI_SUCCESS; |
| 991 | } |
| 992 | |
| 993 | /* |
| 994 | * Unregisters all doorbell handles that were previously |
| 995 | * registered with vmci_ctx_dbell_create. |
| 996 | */ |
| 997 | int vmci_ctx_dbell_destroy_all(u32 context_id) |
| 998 | { |
| 999 | struct vmci_ctx *context; |
| 1000 | struct vmci_handle handle; |
| 1001 | |
| 1002 | if (context_id == VMCI_INVALID_ID) |
| 1003 | return VMCI_ERROR_INVALID_ARGS; |
| 1004 | |
| 1005 | context = vmci_ctx_get(context_id); |
| 1006 | if (context == NULL) |
| 1007 | return VMCI_ERROR_NOT_FOUND; |
| 1008 | |
| 1009 | spin_lock(&context->lock); |
| 1010 | do { |
| 1011 | struct vmci_handle_arr *arr = context->doorbell_array; |
| 1012 | handle = vmci_handle_arr_remove_tail(arr); |
| 1013 | } while (!vmci_handle_is_invalid(handle)); |
| 1014 | do { |
| 1015 | struct vmci_handle_arr *arr = context->pending_doorbell_array; |
| 1016 | handle = vmci_handle_arr_remove_tail(arr); |
| 1017 | } while (!vmci_handle_is_invalid(handle)); |
| 1018 | spin_unlock(&context->lock); |
| 1019 | |
| 1020 | vmci_ctx_put(context); |
| 1021 | |
| 1022 | return VMCI_SUCCESS; |
| 1023 | } |
| 1024 | |
| 1025 | /* |
| 1026 | * Registers a notification of a doorbell handle initiated by the |
| 1027 | * specified source context. The notification of doorbells are |
| 1028 | * subject to the same isolation rules as datagram delivery. To |
| 1029 | * allow host side senders of notifications a finer granularity |
| 1030 | * of sender rights than those assigned to the sending context |
| 1031 | * itself, the host context is required to specify a different |
| 1032 | * set of privilege flags that will override the privileges of |
| 1033 | * the source context. |
| 1034 | */ |
| 1035 | int vmci_ctx_notify_dbell(u32 src_cid, |
| 1036 | struct vmci_handle handle, |
| 1037 | u32 src_priv_flags) |
| 1038 | { |
| 1039 | struct vmci_ctx *dst_context; |
| 1040 | int result; |
| 1041 | |
| 1042 | if (vmci_handle_is_invalid(handle)) |
| 1043 | return VMCI_ERROR_INVALID_ARGS; |
| 1044 | |
| 1045 | /* Get the target VM's VMCI context. */ |
| 1046 | dst_context = vmci_ctx_get(handle.context); |
| 1047 | if (!dst_context) { |
| 1048 | pr_devel("Invalid context (ID=0x%x)\n", handle.context); |
| 1049 | return VMCI_ERROR_NOT_FOUND; |
| 1050 | } |
| 1051 | |
| 1052 | if (src_cid != handle.context) { |
| 1053 | u32 dst_priv_flags; |
| 1054 | |
| 1055 | if (VMCI_CONTEXT_IS_VM(src_cid) && |
| 1056 | VMCI_CONTEXT_IS_VM(handle.context)) { |
| 1057 | pr_devel("Doorbell notification from VM to VM not supported (src=0x%x, dst=0x%x)\n", |
| 1058 | src_cid, handle.context); |
| 1059 | result = VMCI_ERROR_DST_UNREACHABLE; |
| 1060 | goto out; |
| 1061 | } |
| 1062 | |
| 1063 | result = vmci_dbell_get_priv_flags(handle, &dst_priv_flags); |
| 1064 | if (result < VMCI_SUCCESS) { |
| 1065 | pr_warn("Failed to get privilege flags for destination (handle=0x%x:0x%x)\n", |
| 1066 | handle.context, handle.resource); |
| 1067 | goto out; |
| 1068 | } |
| 1069 | |
| 1070 | if (src_cid != VMCI_HOST_CONTEXT_ID || |
| 1071 | src_priv_flags == VMCI_NO_PRIVILEGE_FLAGS) { |
| 1072 | src_priv_flags = vmci_context_get_priv_flags(src_cid); |
| 1073 | } |
| 1074 | |
| 1075 | if (vmci_deny_interaction(src_priv_flags, dst_priv_flags)) { |
| 1076 | result = VMCI_ERROR_NO_ACCESS; |
| 1077 | goto out; |
| 1078 | } |
| 1079 | } |
| 1080 | |
| 1081 | if (handle.context == VMCI_HOST_CONTEXT_ID) { |
| 1082 | result = vmci_dbell_host_context_notify(src_cid, handle); |
| 1083 | } else { |
| 1084 | spin_lock(&dst_context->lock); |
| 1085 | |
| 1086 | if (!vmci_handle_arr_has_entry(dst_context->doorbell_array, |
| 1087 | handle)) { |
| 1088 | result = VMCI_ERROR_NOT_FOUND; |
| 1089 | } else { |
| 1090 | if (!vmci_handle_arr_has_entry( |
| 1091 | dst_context->pending_doorbell_array, |
| 1092 | handle)) { |
| 1093 | vmci_handle_arr_append_entry( |
| 1094 | &dst_context->pending_doorbell_array, |
| 1095 | handle); |
| 1096 | |
| 1097 | ctx_signal_notify(dst_context); |
| 1098 | wake_up(&dst_context->host_context.wait_queue); |
| 1099 | |
| 1100 | } |
| 1101 | result = VMCI_SUCCESS; |
| 1102 | } |
| 1103 | spin_unlock(&dst_context->lock); |
| 1104 | } |
| 1105 | |
| 1106 | out: |
| 1107 | vmci_ctx_put(dst_context); |
| 1108 | |
| 1109 | return result; |
| 1110 | } |
| 1111 | |
| 1112 | bool vmci_ctx_supports_host_qp(struct vmci_ctx *context) |
| 1113 | { |
| 1114 | return context && context->user_version >= VMCI_VERSION_HOSTQP; |
| 1115 | } |
| 1116 | |
| 1117 | /* |
| 1118 | * Registers that a new queue pair handle has been allocated by |
| 1119 | * the context. |
| 1120 | */ |
| 1121 | int vmci_ctx_qp_create(struct vmci_ctx *context, struct vmci_handle handle) |
| 1122 | { |
| 1123 | int result; |
| 1124 | |
| 1125 | if (context == NULL || vmci_handle_is_invalid(handle)) |
| 1126 | return VMCI_ERROR_INVALID_ARGS; |
| 1127 | |
| 1128 | if (!vmci_handle_arr_has_entry(context->queue_pair_array, handle)) { |
| 1129 | vmci_handle_arr_append_entry(&context->queue_pair_array, |
| 1130 | handle); |
| 1131 | result = VMCI_SUCCESS; |
| 1132 | } else { |
| 1133 | result = VMCI_ERROR_DUPLICATE_ENTRY; |
| 1134 | } |
| 1135 | |
| 1136 | return result; |
| 1137 | } |
| 1138 | |
| 1139 | /* |
| 1140 | * Unregisters a queue pair handle that was previously registered |
| 1141 | * with vmci_ctx_qp_create. |
| 1142 | */ |
| 1143 | int vmci_ctx_qp_destroy(struct vmci_ctx *context, struct vmci_handle handle) |
| 1144 | { |
| 1145 | struct vmci_handle hndl; |
| 1146 | |
| 1147 | if (context == NULL || vmci_handle_is_invalid(handle)) |
| 1148 | return VMCI_ERROR_INVALID_ARGS; |
| 1149 | |
| 1150 | hndl = vmci_handle_arr_remove_entry(context->queue_pair_array, handle); |
| 1151 | |
| 1152 | return vmci_handle_is_invalid(hndl) ? |
| 1153 | VMCI_ERROR_NOT_FOUND : VMCI_SUCCESS; |
| 1154 | } |
| 1155 | |
| 1156 | /* |
| 1157 | * Determines whether a given queue pair handle is registered |
| 1158 | * with the given context. |
| 1159 | */ |
| 1160 | bool vmci_ctx_qp_exists(struct vmci_ctx *context, struct vmci_handle handle) |
| 1161 | { |
| 1162 | if (context == NULL || vmci_handle_is_invalid(handle)) |
| 1163 | return false; |
| 1164 | |
| 1165 | return vmci_handle_arr_has_entry(context->queue_pair_array, handle); |
| 1166 | } |
| 1167 | |
| 1168 | /* |
| 1169 | * vmci_context_get_priv_flags() - Retrieve privilege flags. |
| 1170 | * @context_id: The context ID of the VMCI context. |
| 1171 | * |
| 1172 | * Retrieves privilege flags of the given VMCI context ID. |
| 1173 | */ |
| 1174 | u32 vmci_context_get_priv_flags(u32 context_id) |
| 1175 | { |
| 1176 | if (vmci_host_code_active()) { |
| 1177 | u32 flags; |
| 1178 | struct vmci_ctx *context; |
| 1179 | |
| 1180 | context = vmci_ctx_get(context_id); |
| 1181 | if (!context) |
| 1182 | return VMCI_LEAST_PRIVILEGE_FLAGS; |
| 1183 | |
| 1184 | flags = context->priv_flags; |
| 1185 | vmci_ctx_put(context); |
| 1186 | return flags; |
| 1187 | } |
| 1188 | return VMCI_NO_PRIVILEGE_FLAGS; |
| 1189 | } |
| 1190 | EXPORT_SYMBOL_GPL(vmci_context_get_priv_flags); |
| 1191 | |
| 1192 | /* |
| 1193 | * vmci_is_context_owner() - Determimnes if user is the context owner |
| 1194 | * @context_id: The context ID of the VMCI context. |
| 1195 | * @uid: The host user id (real kernel value). |
| 1196 | * |
| 1197 | * Determines whether a given UID is the owner of given VMCI context. |
| 1198 | */ |
| 1199 | bool vmci_is_context_owner(u32 context_id, kuid_t uid) |
| 1200 | { |
| 1201 | bool is_owner = false; |
| 1202 | |
| 1203 | if (vmci_host_code_active()) { |
| 1204 | struct vmci_ctx *context = vmci_ctx_get(context_id); |
| 1205 | if (context) { |
| 1206 | if (context->cred) |
| 1207 | is_owner = uid_eq(context->cred->uid, uid); |
| 1208 | vmci_ctx_put(context); |
| 1209 | } |
| 1210 | } |
| 1211 | |
| 1212 | return is_owner; |
| 1213 | } |
| 1214 | EXPORT_SYMBOL_GPL(vmci_is_context_owner); |