/*- * Copyright (c) 2018 VMware, Inc. * * SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0) */ /* VMCI QueuePair API implementation. */ #include #include "vmci.h" #include "vmci_driver.h" #include "vmci_event.h" #include "vmci_kernel_api.h" #include "vmci_kernel_defs.h" #include "vmci_queue_pair.h" #define LGPFX "vmci_queue_pair: " struct queue_pair_entry { vmci_list_item(queue_pair_entry) list_item; struct vmci_handle handle; vmci_id peer; uint32_t flags; uint64_t produce_size; uint64_t consume_size; uint32_t ref_count; }; struct qp_guest_endpoint { struct queue_pair_entry qp; uint64_t num_ppns; void *produce_q; void *consume_q; bool hibernate_failure; struct ppn_set ppn_set; }; struct queue_pair_list { vmci_list(queue_pair_entry) head; volatile int hibernate; vmci_mutex mutex; }; #define QPE_NUM_PAGES(_QPE) \ ((uint32_t)(CEILING(_QPE.produce_size, PAGE_SIZE) + \ CEILING(_QPE.consume_size, PAGE_SIZE) + 2)) static struct queue_pair_list qp_guest_endpoints; static struct queue_pair_entry *queue_pair_list_find_entry( struct queue_pair_list *qp_list, struct vmci_handle handle); static void queue_pair_list_add_entry(struct queue_pair_list *qp_list, struct queue_pair_entry *entry); static void queue_pair_list_remove_entry(struct queue_pair_list *qp_list, struct queue_pair_entry *entry); static struct queue_pair_entry *queue_pair_list_get_head( struct queue_pair_list *qp_list); static int queue_pair_notify_peer_local(bool attach, struct vmci_handle handle); static struct qp_guest_endpoint *qp_guest_endpoint_create( struct vmci_handle handle, vmci_id peer, uint32_t flags, uint64_t produce_size, uint64_t consume_size, void *produce_q, void *consume_q); static void qp_guest_endpoint_destroy(struct qp_guest_endpoint *entry); static int vmci_queue_pair_alloc_hypercall( const struct qp_guest_endpoint *entry); static int vmci_queue_pair_alloc_guest_work(struct vmci_handle *handle, struct vmci_queue **produce_q, uint64_t produce_size, struct vmci_queue **consume_q, uint64_t consume_size, vmci_id peer, uint32_t flags, vmci_privilege_flags priv_flags); static int vmci_queue_pair_detach_guest_work(struct vmci_handle handle); static int vmci_queue_pair_detach_hypercall(struct vmci_handle handle); /* *------------------------------------------------------------------------------ * * vmci_queue_pair_alloc -- * * Allocates a VMCI QueuePair. Only checks validity of input arguments. The * real work is done in the host or guest specific function. * * Results: * VMCI_SUCCESS on success, appropriate error code otherwise. * * Side effects: * None. * *------------------------------------------------------------------------------ */ int vmci_queue_pair_alloc(struct vmci_handle *handle, struct vmci_queue **produce_q, uint64_t produce_size, struct vmci_queue **consume_q, uint64_t consume_size, vmci_id peer, uint32_t flags, vmci_privilege_flags priv_flags) { if (!handle || !produce_q || !consume_q || (!produce_size && !consume_size) || (flags & ~VMCI_QP_ALL_FLAGS)) return (VMCI_ERROR_INVALID_ARGS); return (vmci_queue_pair_alloc_guest_work(handle, produce_q, produce_size, consume_q, consume_size, peer, flags, priv_flags)); } /* *------------------------------------------------------------------------------ * * vmci_queue_pair_detach -- * * Detaches from a VMCI QueuePair. Only checks validity of input argument. * Real work is done in the host or guest specific function. * * Results: * Success or failure. * * Side effects: * Memory is freed. * *------------------------------------------------------------------------------ */ int vmci_queue_pair_detach(struct vmci_handle handle) { if (VMCI_HANDLE_INVALID(handle)) return (VMCI_ERROR_INVALID_ARGS); return (vmci_queue_pair_detach_guest_work(handle)); } /* *------------------------------------------------------------------------------ * * queue_pair_list_init -- * * Initializes the list of QueuePairs. * * Results: * Success or failure. * * Side effects: * None. * *------------------------------------------------------------------------------ */ static inline int queue_pair_list_init(struct queue_pair_list *qp_list) { int ret; vmci_list_init(&qp_list->head); atomic_store_int(&qp_list->hibernate, 0); ret = vmci_mutex_init(&qp_list->mutex, "VMCI QP List lock"); return (ret); } /* *------------------------------------------------------------------------------ * * queue_pair_list_destroy -- * * Destroy the list's mutex. * * Results: * None. * * Side effects: * None. * *------------------------------------------------------------------------------ */ static inline void queue_pair_list_destroy(struct queue_pair_list *qp_list) { vmci_mutex_destroy(&qp_list->mutex); vmci_list_init(&qp_list->head); } /* *------------------------------------------------------------------------------ * * queue_pair_list_find_entry -- * * Finds the entry in the list corresponding to a given handle. Assumes that * the list is locked. * * Results: * Pointer to entry. * * Side effects: * None. * *------------------------------------------------------------------------------ */ static struct queue_pair_entry * queue_pair_list_find_entry(struct queue_pair_list *qp_list, struct vmci_handle handle) { struct queue_pair_entry *next; if (VMCI_HANDLE_INVALID(handle)) return (NULL); vmci_list_scan(next, &qp_list->head, list_item) { if (VMCI_HANDLE_EQUAL(next->handle, handle)) return (next); } return (NULL); } /* *------------------------------------------------------------------------------ * * queue_pair_list_add_entry -- * * Adds the given entry to the list. Assumes that the list is locked. * * Results: * None. * * Side effects: * None. * *------------------------------------------------------------------------------ */ static void queue_pair_list_add_entry(struct queue_pair_list *qp_list, struct queue_pair_entry *entry) { if (entry) vmci_list_insert(&qp_list->head, entry, list_item); } /* *------------------------------------------------------------------------------ * * queue_pair_list_remove_entry -- * * Removes the given entry from the list. Assumes that the list is locked. * * Results: * None. * * Side effects: * None. * *------------------------------------------------------------------------------ */ static void queue_pair_list_remove_entry(struct queue_pair_list *qp_list, struct queue_pair_entry *entry) { if (entry) vmci_list_remove(entry, list_item); } /* *------------------------------------------------------------------------------ * * queue_pair_list_get_head -- * * Returns the entry from the head of the list. Assumes that the list is * locked. * * Results: * Pointer to entry. * * Side effects: * None. * *------------------------------------------------------------------------------ */ static struct queue_pair_entry * queue_pair_list_get_head(struct queue_pair_list *qp_list) { return (vmci_list_first(&qp_list->head)); } /* *------------------------------------------------------------------------------ * * vmci_qp_guest_endpoints_init -- * * Initalizes data structure state keeping track of queue pair guest * endpoints. * * Results: * VMCI_SUCCESS on success and appropriate failure code otherwise. * * Side effects: * None. * *------------------------------------------------------------------------------ */ int vmci_qp_guest_endpoints_init(void) { return (queue_pair_list_init(&qp_guest_endpoints)); } /* *------------------------------------------------------------------------------ * * vmci_qp_guest_endpoints_exit -- * * Destroys all guest queue pair endpoints. If active guest queue pairs * still exist, hypercalls to attempt detach from these queue pairs will be * made. Any failure to detach is silently ignored. * * Results: * None. * * Side effects: * None. * *------------------------------------------------------------------------------ */ void vmci_qp_guest_endpoints_exit(void) { struct qp_guest_endpoint *entry; if (!vmci_mutex_initialized(&qp_guest_endpoints.mutex)) return; vmci_mutex_acquire(&qp_guest_endpoints.mutex); while ((entry = (struct qp_guest_endpoint *)queue_pair_list_get_head( &qp_guest_endpoints)) != NULL) { /* * Don't make a hypercall for local QueuePairs. */ if (!(entry->qp.flags & VMCI_QPFLAG_LOCAL)) vmci_queue_pair_detach_hypercall(entry->qp.handle); /* * We cannot fail the exit, so let's reset ref_count. */ entry->qp.ref_count = 0; queue_pair_list_remove_entry(&qp_guest_endpoints, &entry->qp); qp_guest_endpoint_destroy(entry); } atomic_store_int(&qp_guest_endpoints.hibernate, 0); vmci_mutex_release(&qp_guest_endpoints.mutex); queue_pair_list_destroy(&qp_guest_endpoints); } /* *------------------------------------------------------------------------------ * * vmci_qp_guest_endpoints_sync -- * * Use this as a synchronization point when setting globals, for example, * during device shutdown. * * Results: * true. * * Side effects: * None. * *------------------------------------------------------------------------------ */ void vmci_qp_guest_endpoints_sync(void) { vmci_mutex_acquire(&qp_guest_endpoints.mutex); vmci_mutex_release(&qp_guest_endpoints.mutex); } /* *------------------------------------------------------------------------------ * * qp_guest_endpoint_create -- * * Allocates and initializes a qp_guest_endpoint structure. Allocates a * QueuePair rid (and handle) iff the given entry has an invalid handle. * 0 through VMCI_RESERVED_RESOURCE_ID_MAX are reserved handles. Assumes * that the QP list mutex is held by the caller. * * Results: * Pointer to structure intialized. * * Side effects: * None. * *------------------------------------------------------------------------------ */ struct qp_guest_endpoint * qp_guest_endpoint_create(struct vmci_handle handle, vmci_id peer, uint32_t flags, uint64_t produce_size, uint64_t consume_size, void *produce_q, void *consume_q) { struct qp_guest_endpoint *entry; static vmci_id queue_pair_rid; const uint64_t num_ppns = CEILING(produce_size, PAGE_SIZE) + CEILING(consume_size, PAGE_SIZE) + 2; /* One page each for the queue headers. */ queue_pair_rid = VMCI_RESERVED_RESOURCE_ID_MAX + 1; ASSERT((produce_size || consume_size) && produce_q && consume_q); if (VMCI_HANDLE_INVALID(handle)) { vmci_id context_id = vmci_get_context_id(); vmci_id old_rid = queue_pair_rid; /* * Generate a unique QueuePair rid. Keep on trying until we * wrap around in the RID space. */ ASSERT(old_rid > VMCI_RESERVED_RESOURCE_ID_MAX); do { handle = VMCI_MAKE_HANDLE(context_id, queue_pair_rid); entry = (struct qp_guest_endpoint *) queue_pair_list_find_entry(&qp_guest_endpoints, handle); queue_pair_rid++; if (UNLIKELY(!queue_pair_rid)) { /* * Skip the reserved rids. */ queue_pair_rid = VMCI_RESERVED_RESOURCE_ID_MAX + 1; } } while (entry && queue_pair_rid != old_rid); if (UNLIKELY(entry != NULL)) { ASSERT(queue_pair_rid == old_rid); /* * We wrapped around --- no rids were free. */ return (NULL); } } ASSERT(!VMCI_HANDLE_INVALID(handle) && queue_pair_list_find_entry(&qp_guest_endpoints, handle) == NULL); entry = vmci_alloc_kernel_mem(sizeof(*entry), VMCI_MEMORY_NORMAL); if (entry) { entry->qp.handle = handle; entry->qp.peer = peer; entry->qp.flags = flags; entry->qp.produce_size = produce_size; entry->qp.consume_size = consume_size; entry->qp.ref_count = 0; entry->num_ppns = num_ppns; memset(&entry->ppn_set, 0, sizeof(entry->ppn_set)); entry->produce_q = produce_q; entry->consume_q = consume_q; } return (entry); } /* *------------------------------------------------------------------------------ * * qp_guest_endpoint_destroy -- * * Frees a qp_guest_endpoint structure. * * Results: * None. * * Side effects: * None. * *------------------------------------------------------------------------------ */ void qp_guest_endpoint_destroy(struct qp_guest_endpoint *entry) { ASSERT(entry); ASSERT(entry->qp.ref_count == 0); vmci_free_ppn_set(&entry->ppn_set); vmci_free_queue(entry->produce_q, entry->qp.produce_size); vmci_free_queue(entry->consume_q, entry->qp.consume_size); vmci_free_kernel_mem(entry, sizeof(*entry)); } /* *------------------------------------------------------------------------------ * * vmci_queue_pair_alloc_hypercall -- * * Helper to make a QueuePairAlloc hypercall when the driver is * supporting a guest device. * * Results: * Result of the hypercall. * * Side effects: * Memory is allocated & freed. * *------------------------------------------------------------------------------ */ static int vmci_queue_pair_alloc_hypercall(const struct qp_guest_endpoint *entry) { struct vmci_queue_pair_alloc_msg *alloc_msg; size_t msg_size; int result; if (!entry || entry->num_ppns <= 2) return (VMCI_ERROR_INVALID_ARGS); ASSERT(!(entry->qp.flags & VMCI_QPFLAG_LOCAL)); msg_size = sizeof(*alloc_msg) + (size_t)entry->num_ppns * sizeof(PPN); alloc_msg = vmci_alloc_kernel_mem(msg_size, VMCI_MEMORY_NORMAL); if (!alloc_msg) return (VMCI_ERROR_NO_MEM); alloc_msg->hdr.dst = VMCI_MAKE_HANDLE(VMCI_HYPERVISOR_CONTEXT_ID, VMCI_QUEUEPAIR_ALLOC); alloc_msg->hdr.src = VMCI_ANON_SRC_HANDLE; alloc_msg->hdr.payload_size = msg_size - VMCI_DG_HEADERSIZE; alloc_msg->handle = entry->qp.handle; alloc_msg->peer = entry->qp.peer; alloc_msg->flags = entry->qp.flags; alloc_msg->produce_size = entry->qp.produce_size; alloc_msg->consume_size = entry->qp.consume_size; alloc_msg->num_ppns = entry->num_ppns; result = vmci_populate_ppn_list((uint8_t *)alloc_msg + sizeof(*alloc_msg), &entry->ppn_set); if (result == VMCI_SUCCESS) result = vmci_send_datagram((struct vmci_datagram *)alloc_msg); vmci_free_kernel_mem(alloc_msg, msg_size); return (result); } /* *------------------------------------------------------------------------------ * * vmci_queue_pair_alloc_guest_work -- * * This functions handles the actual allocation of a VMCI queue pair guest * endpoint. Allocates physical pages for the queue pair. It makes OS * dependent calls through generic wrappers. * * Results: * Success or failure. * * Side effects: * Memory is allocated. * *------------------------------------------------------------------------------ */ static int vmci_queue_pair_alloc_guest_work(struct vmci_handle *handle, struct vmci_queue **produce_q, uint64_t produce_size, struct vmci_queue **consume_q, uint64_t consume_size, vmci_id peer, uint32_t flags, vmci_privilege_flags priv_flags) { struct qp_guest_endpoint *queue_pair_entry = NULL; void *my_consume_q = NULL; void *my_produce_q = NULL; const uint64_t num_consume_pages = CEILING(consume_size, PAGE_SIZE) + 1; const uint64_t num_produce_pages = CEILING(produce_size, PAGE_SIZE) + 1; int result; ASSERT(handle && produce_q && consume_q && (produce_size || consume_size)); if (priv_flags != VMCI_NO_PRIVILEGE_FLAGS) return (VMCI_ERROR_NO_ACCESS); vmci_mutex_acquire(&qp_guest_endpoints.mutex); if ((atomic_load_int(&qp_guest_endpoints.hibernate) == 1) && !(flags & VMCI_QPFLAG_LOCAL)) { /* * While guest OS is in hibernate state, creating non-local * queue pairs is not allowed after the point where the VMCI * guest driver converted the existing queue pairs to local * ones. */ result = VMCI_ERROR_UNAVAILABLE; goto error; } if ((queue_pair_entry = (struct qp_guest_endpoint *)queue_pair_list_find_entry( &qp_guest_endpoints, *handle)) != NULL) { if (queue_pair_entry->qp.flags & VMCI_QPFLAG_LOCAL) { /* Local attach case. */ if (queue_pair_entry->qp.ref_count > 1) { VMCI_LOG_DEBUG(LGPFX"Error attempting to " "attach more than once.\n"); result = VMCI_ERROR_UNAVAILABLE; goto error_keep_entry; } if (queue_pair_entry->qp.produce_size != consume_size || queue_pair_entry->qp.consume_size != produce_size || queue_pair_entry->qp.flags != (flags & ~VMCI_QPFLAG_ATTACH_ONLY)) { VMCI_LOG_DEBUG(LGPFX"Error mismatched " "queue pair in local attach.\n"); result = VMCI_ERROR_QUEUEPAIR_MISMATCH; goto error_keep_entry; } /* * Do a local attach. We swap the consume and produce * queues for the attacher and deliver an attach event. */ result = queue_pair_notify_peer_local(true, *handle); if (result < VMCI_SUCCESS) goto error_keep_entry; my_produce_q = queue_pair_entry->consume_q; my_consume_q = queue_pair_entry->produce_q; goto out; } result = VMCI_ERROR_ALREADY_EXISTS; goto error_keep_entry; } my_produce_q = vmci_alloc_queue(produce_size, flags); if (!my_produce_q) { VMCI_LOG_WARNING(LGPFX"Error allocating pages for produce " "queue.\n"); result = VMCI_ERROR_NO_MEM; goto error; } my_consume_q = vmci_alloc_queue(consume_size, flags); if (!my_consume_q) { VMCI_LOG_WARNING(LGPFX"Error allocating pages for consume " "queue.\n"); result = VMCI_ERROR_NO_MEM; goto error; } queue_pair_entry = qp_guest_endpoint_create(*handle, peer, flags, produce_size, consume_size, my_produce_q, my_consume_q); if (!queue_pair_entry) { VMCI_LOG_WARNING(LGPFX"Error allocating memory in %s.\n", __FUNCTION__); result = VMCI_ERROR_NO_MEM; goto error; } result = vmci_alloc_ppn_set(my_produce_q, num_produce_pages, my_consume_q, num_consume_pages, &queue_pair_entry->ppn_set); if (result < VMCI_SUCCESS) { VMCI_LOG_WARNING(LGPFX"vmci_alloc_ppn_set failed.\n"); goto error; } /* * It's only necessary to notify the host if this queue pair will be * attached to from another context. */ if (queue_pair_entry->qp.flags & VMCI_QPFLAG_LOCAL) { /* Local create case. */ vmci_id context_id = vmci_get_context_id(); /* * Enforce similar checks on local queue pairs as we do for * regular ones. The handle's context must match the creator * or attacher context id (here they are both the current * context id) and the attach-only flag cannot exist during * create. We also ensure specified peer is this context or * an invalid one. */ if (queue_pair_entry->qp.handle.context != context_id || (queue_pair_entry->qp.peer != VMCI_INVALID_ID && queue_pair_entry->qp.peer != context_id)) { result = VMCI_ERROR_NO_ACCESS; goto error; } if (queue_pair_entry->qp.flags & VMCI_QPFLAG_ATTACH_ONLY) { result = VMCI_ERROR_NOT_FOUND; goto error; } } else { result = vmci_queue_pair_alloc_hypercall(queue_pair_entry); if (result < VMCI_SUCCESS) { VMCI_LOG_WARNING( LGPFX"vmci_queue_pair_alloc_hypercall result = " "%d.\n", result); goto error; } } queue_pair_list_add_entry(&qp_guest_endpoints, &queue_pair_entry->qp); out: queue_pair_entry->qp.ref_count++; *handle = queue_pair_entry->qp.handle; *produce_q = (struct vmci_queue *)my_produce_q; *consume_q = (struct vmci_queue *)my_consume_q; /* * We should initialize the queue pair header pages on a local queue * pair create. For non-local queue pairs, the hypervisor initializes * the header pages in the create step. */ if ((queue_pair_entry->qp.flags & VMCI_QPFLAG_LOCAL) && queue_pair_entry->qp.ref_count == 1) { vmci_queue_header_init((*produce_q)->q_header, *handle); vmci_queue_header_init((*consume_q)->q_header, *handle); } vmci_mutex_release(&qp_guest_endpoints.mutex); return (VMCI_SUCCESS); error: vmci_mutex_release(&qp_guest_endpoints.mutex); if (queue_pair_entry) { /* The queues will be freed inside the destroy routine. */ qp_guest_endpoint_destroy(queue_pair_entry); } else { if (my_produce_q) vmci_free_queue(my_produce_q, produce_size); if (my_consume_q) vmci_free_queue(my_consume_q, consume_size); } return (result); error_keep_entry: /* This path should only be used when an existing entry was found. */ ASSERT(queue_pair_entry->qp.ref_count > 0); vmci_mutex_release(&qp_guest_endpoints.mutex); return (result); } /* *------------------------------------------------------------------------------ * * vmci_queue_pair_detach_hypercall -- * * Helper to make a QueuePairDetach hypercall when the driver is supporting * a guest device. * * Results: * Result of the hypercall. * * Side effects: * None. * *------------------------------------------------------------------------------ */ int vmci_queue_pair_detach_hypercall(struct vmci_handle handle) { struct vmci_queue_pair_detach_msg detach_msg; detach_msg.hdr.dst = VMCI_MAKE_HANDLE(VMCI_HYPERVISOR_CONTEXT_ID, VMCI_QUEUEPAIR_DETACH); detach_msg.hdr.src = VMCI_ANON_SRC_HANDLE; detach_msg.hdr.payload_size = sizeof(handle); detach_msg.handle = handle; return (vmci_send_datagram((struct vmci_datagram *)&detach_msg)); } /* *------------------------------------------------------------------------------ * * vmci_queue_pair_detach_guest_work -- * * Helper for VMCI QueuePair detach interface. Frees the physical pages for * the queue pair. * * Results: * Success or failure. * * Side effects: * Memory may be freed. * *------------------------------------------------------------------------------ */ static int vmci_queue_pair_detach_guest_work(struct vmci_handle handle) { struct qp_guest_endpoint *entry; int result; uint32_t ref_count; ASSERT(!VMCI_HANDLE_INVALID(handle)); vmci_mutex_acquire(&qp_guest_endpoints.mutex); entry = (struct qp_guest_endpoint *)queue_pair_list_find_entry( &qp_guest_endpoints, handle); if (!entry) { vmci_mutex_release(&qp_guest_endpoints.mutex); return (VMCI_ERROR_NOT_FOUND); } ASSERT(entry->qp.ref_count >= 1); if (entry->qp.flags & VMCI_QPFLAG_LOCAL) { result = VMCI_SUCCESS; if (entry->qp.ref_count > 1) { result = queue_pair_notify_peer_local(false, handle); /* * We can fail to notify a local queuepair because we * can't allocate. We still want to release the entry * if that happens, so don't bail out yet. */ } } else { result = vmci_queue_pair_detach_hypercall(handle); if (entry->hibernate_failure) { if (result == VMCI_ERROR_NOT_FOUND) { /* * If a queue pair detach failed when entering * hibernation, the guest driver and the device * may disagree on its existence when coming * out of hibernation. The guest driver will * regard it as a non-local queue pair, but * the device state is gone, since the device * has been powered off. In this case, we * treat the queue pair as a local queue pair * with no peer. */ ASSERT(entry->qp.ref_count == 1); result = VMCI_SUCCESS; } } if (result < VMCI_SUCCESS) { /* * We failed to notify a non-local queuepair. That other * queuepair might still be accessing the shared * memory, so don't release the entry yet. It will get * cleaned up by vmci_queue_pair_Exit() if necessary * (assuming we are going away, otherwise why did this * fail?). */ vmci_mutex_release(&qp_guest_endpoints.mutex); return (result); } } /* * If we get here then we either failed to notify a local queuepair, or * we succeeded in all cases. Release the entry if required. */ entry->qp.ref_count--; if (entry->qp.ref_count == 0) queue_pair_list_remove_entry(&qp_guest_endpoints, &entry->qp); /* If we didn't remove the entry, this could change once we unlock. */ ref_count = entry ? entry->qp.ref_count : 0xffffffff; /* * Value does not matter, silence the * compiler. */ vmci_mutex_release(&qp_guest_endpoints.mutex); if (ref_count == 0) qp_guest_endpoint_destroy(entry); return (result); } /* *------------------------------------------------------------------------------ * * queue_pair_notify_peer_local -- * * Dispatches a queue pair event message directly into the local event * queue. * * Results: * VMCI_SUCCESS on success, error code otherwise * * Side effects: * None. * *------------------------------------------------------------------------------ */ static int queue_pair_notify_peer_local(bool attach, struct vmci_handle handle) { struct vmci_event_msg *e_msg; struct vmci_event_payload_qp *e_payload; /* buf is only 48 bytes. */ vmci_id context_id; context_id = vmci_get_context_id(); char buf[sizeof(*e_msg) + sizeof(*e_payload)]; e_msg = (struct vmci_event_msg *)buf; e_payload = vmci_event_msg_payload(e_msg); e_msg->hdr.dst = VMCI_MAKE_HANDLE(context_id, VMCI_EVENT_HANDLER); e_msg->hdr.src = VMCI_MAKE_HANDLE(VMCI_HYPERVISOR_CONTEXT_ID, VMCI_CONTEXT_RESOURCE_ID); e_msg->hdr.payload_size = sizeof(*e_msg) + sizeof(*e_payload) - sizeof(e_msg->hdr); e_msg->event_data.event = attach ? VMCI_EVENT_QP_PEER_ATTACH : VMCI_EVENT_QP_PEER_DETACH; e_payload->peer_id = context_id; e_payload->handle = handle; return (vmci_event_dispatch((struct vmci_datagram *)e_msg)); }