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28d6692cd8
VMCI Context code maintains state for vmci and allows the driver to communicate with multiple VMs. Signed-off-by: George Zhang <georgezhang@vmware.com> Acked-by: Andy king <acking@vmware.com> Acked-by: Dmitry Torokhov <dtor@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1215 lines
31 KiB
C
1215 lines
31 KiB
C
/*
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* VMware VMCI Driver
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*
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* Copyright (C) 2012 VMware, Inc. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation version 2 and no later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* for more details.
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*/
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#include <linux/vmw_vmci_defs.h>
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#include <linux/vmw_vmci_api.h>
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#include <linux/highmem.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include "vmci_queue_pair.h"
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#include "vmci_datagram.h"
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#include "vmci_doorbell.h"
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#include "vmci_context.h"
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#include "vmci_driver.h"
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#include "vmci_event.h"
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/*
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* List of current VMCI contexts. Contexts can be added by
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* vmci_ctx_create() and removed via vmci_ctx_destroy().
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* These, along with context lookup, are protected by the
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* list structure's lock.
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*/
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static struct {
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struct list_head head;
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spinlock_t lock; /* Spinlock for context list operations */
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} ctx_list = {
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.head = LIST_HEAD_INIT(ctx_list.head),
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.lock = __SPIN_LOCK_UNLOCKED(ctx_list.lock),
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};
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/* Used by contexts that did not set up notify flag pointers */
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static bool ctx_dummy_notify;
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static void ctx_signal_notify(struct vmci_ctx *context)
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{
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*context->notify = true;
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}
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static void ctx_clear_notify(struct vmci_ctx *context)
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{
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*context->notify = false;
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}
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/*
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* If nothing requires the attention of the guest, clears both
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* notify flag and call.
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*/
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static void ctx_clear_notify_call(struct vmci_ctx *context)
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{
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if (context->pending_datagrams == 0 &&
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vmci_handle_arr_get_size(context->pending_doorbell_array) == 0)
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ctx_clear_notify(context);
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}
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/*
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* Sets the context's notify flag iff datagrams are pending for this
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* context. Called from vmci_setup_notify().
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*/
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void vmci_ctx_check_signal_notify(struct vmci_ctx *context)
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{
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spin_lock(&context->lock);
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if (context->pending_datagrams)
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ctx_signal_notify(context);
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spin_unlock(&context->lock);
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}
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/*
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* Allocates and initializes a VMCI context.
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*/
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struct vmci_ctx *vmci_ctx_create(u32 cid, u32 priv_flags,
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uintptr_t event_hnd,
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int user_version,
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const struct cred *cred)
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{
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struct vmci_ctx *context;
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int error;
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if (cid == VMCI_INVALID_ID) {
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pr_devel("Invalid context ID for VMCI context\n");
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error = -EINVAL;
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goto err_out;
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}
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if (priv_flags & ~VMCI_PRIVILEGE_ALL_FLAGS) {
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pr_devel("Invalid flag (flags=0x%x) for VMCI context\n",
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priv_flags);
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error = -EINVAL;
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goto err_out;
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}
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if (user_version == 0) {
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pr_devel("Invalid suer_version %d\n", user_version);
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error = -EINVAL;
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goto err_out;
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}
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context = kzalloc(sizeof(*context), GFP_KERNEL);
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if (!context) {
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pr_warn("Failed to allocate memory for VMCI context\n");
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error = -EINVAL;
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goto err_out;
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}
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kref_init(&context->kref);
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spin_lock_init(&context->lock);
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INIT_LIST_HEAD(&context->list_item);
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INIT_LIST_HEAD(&context->datagram_queue);
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INIT_LIST_HEAD(&context->notifier_list);
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/* Initialize host-specific VMCI context. */
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init_waitqueue_head(&context->host_context.wait_queue);
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context->queue_pair_array = vmci_handle_arr_create(0);
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if (!context->queue_pair_array) {
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error = -ENOMEM;
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goto err_free_ctx;
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}
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context->doorbell_array = vmci_handle_arr_create(0);
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if (!context->doorbell_array) {
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error = -ENOMEM;
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goto err_free_qp_array;
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}
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context->pending_doorbell_array = vmci_handle_arr_create(0);
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if (!context->pending_doorbell_array) {
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error = -ENOMEM;
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goto err_free_db_array;
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}
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context->user_version = user_version;
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context->priv_flags = priv_flags;
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if (cred)
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context->cred = get_cred(cred);
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context->notify = &ctx_dummy_notify;
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context->notify_page = NULL;
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/*
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* If we collide with an existing context we generate a new
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* and use it instead. The VMX will determine if regeneration
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* is okay. Since there isn't 4B - 16 VMs running on a given
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* host, the below loop will terminate.
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*/
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spin_lock(&ctx_list.lock);
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while (vmci_ctx_exists(cid)) {
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/* We reserve the lowest 16 ids for fixed contexts. */
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cid = max(cid, VMCI_RESERVED_CID_LIMIT - 1) + 1;
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if (cid == VMCI_INVALID_ID)
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cid = VMCI_RESERVED_CID_LIMIT;
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}
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context->cid = cid;
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list_add_tail_rcu(&context->list_item, &ctx_list.head);
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spin_unlock(&ctx_list.lock);
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return context;
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err_free_db_array:
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vmci_handle_arr_destroy(context->doorbell_array);
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err_free_qp_array:
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vmci_handle_arr_destroy(context->queue_pair_array);
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err_free_ctx:
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kfree(context);
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err_out:
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return ERR_PTR(error);
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}
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/*
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* Destroy VMCI context.
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*/
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void vmci_ctx_destroy(struct vmci_ctx *context)
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{
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spin_lock(&ctx_list.lock);
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list_del_rcu(&context->list_item);
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spin_unlock(&ctx_list.lock);
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synchronize_rcu();
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vmci_ctx_put(context);
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}
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/*
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* Fire notification for all contexts interested in given cid.
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*/
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static int ctx_fire_notification(u32 context_id, u32 priv_flags)
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{
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u32 i, array_size;
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struct vmci_ctx *sub_ctx;
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struct vmci_handle_arr *subscriber_array;
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struct vmci_handle context_handle =
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vmci_make_handle(context_id, VMCI_EVENT_HANDLER);
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/*
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* We create an array to hold the subscribers we find when
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* scanning through all contexts.
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*/
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subscriber_array = vmci_handle_arr_create(0);
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if (subscriber_array == NULL)
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return VMCI_ERROR_NO_MEM;
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/*
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* Scan all contexts to find who is interested in being
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* notified about given contextID.
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*/
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rcu_read_lock();
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list_for_each_entry_rcu(sub_ctx, &ctx_list.head, list_item) {
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struct vmci_handle_list *node;
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/*
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* We only deliver notifications of the removal of
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* contexts, if the two contexts are allowed to
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* interact.
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*/
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if (vmci_deny_interaction(priv_flags, sub_ctx->priv_flags))
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continue;
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list_for_each_entry_rcu(node, &sub_ctx->notifier_list, node) {
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if (!vmci_handle_is_equal(node->handle, context_handle))
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continue;
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vmci_handle_arr_append_entry(&subscriber_array,
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vmci_make_handle(sub_ctx->cid,
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VMCI_EVENT_HANDLER));
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}
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}
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rcu_read_unlock();
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/* Fire event to all subscribers. */
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array_size = vmci_handle_arr_get_size(subscriber_array);
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for (i = 0; i < array_size; i++) {
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int result;
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struct vmci_event_ctx ev;
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ev.msg.hdr.dst = vmci_handle_arr_get_entry(subscriber_array, i);
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ev.msg.hdr.src = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
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VMCI_CONTEXT_RESOURCE_ID);
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ev.msg.hdr.payload_size = sizeof(ev) - sizeof(ev.msg.hdr);
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ev.msg.event_data.event = VMCI_EVENT_CTX_REMOVED;
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ev.payload.context_id = context_id;
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result = vmci_datagram_dispatch(VMCI_HYPERVISOR_CONTEXT_ID,
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&ev.msg.hdr, false);
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if (result < VMCI_SUCCESS) {
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pr_devel("Failed to enqueue event datagram (type=%d) for context (ID=0x%x)\n",
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ev.msg.event_data.event,
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ev.msg.hdr.dst.context);
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/* We continue to enqueue on next subscriber. */
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}
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}
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vmci_handle_arr_destroy(subscriber_array);
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return VMCI_SUCCESS;
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}
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/*
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* Returns the current number of pending datagrams. The call may
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* also serve as a synchronization point for the datagram queue,
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* as no enqueue operations can occur concurrently.
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*/
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int vmci_ctx_pending_datagrams(u32 cid, u32 *pending)
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{
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struct vmci_ctx *context;
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context = vmci_ctx_get(cid);
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if (context == NULL)
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return VMCI_ERROR_INVALID_ARGS;
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spin_lock(&context->lock);
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if (pending)
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*pending = context->pending_datagrams;
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spin_unlock(&context->lock);
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vmci_ctx_put(context);
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return VMCI_SUCCESS;
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}
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/*
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* Queues a VMCI datagram for the appropriate target VM context.
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*/
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int vmci_ctx_enqueue_datagram(u32 cid, struct vmci_datagram *dg)
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{
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struct vmci_datagram_queue_entry *dq_entry;
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struct vmci_ctx *context;
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struct vmci_handle dg_src;
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size_t vmci_dg_size;
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vmci_dg_size = VMCI_DG_SIZE(dg);
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if (vmci_dg_size > VMCI_MAX_DG_SIZE) {
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pr_devel("Datagram too large (bytes=%Zu)\n", vmci_dg_size);
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return VMCI_ERROR_INVALID_ARGS;
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}
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/* Get the target VM's VMCI context. */
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context = vmci_ctx_get(cid);
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if (!context) {
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pr_devel("Invalid context (ID=0x%x)\n", cid);
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return VMCI_ERROR_INVALID_ARGS;
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}
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/* Allocate guest call entry and add it to the target VM's queue. */
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dq_entry = kmalloc(sizeof(*dq_entry), GFP_KERNEL);
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if (dq_entry == NULL) {
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pr_warn("Failed to allocate memory for datagram\n");
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vmci_ctx_put(context);
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return VMCI_ERROR_NO_MEM;
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}
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dq_entry->dg = dg;
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dq_entry->dg_size = vmci_dg_size;
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dg_src = dg->src;
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INIT_LIST_HEAD(&dq_entry->list_item);
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spin_lock(&context->lock);
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/*
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* We put a higher limit on datagrams from the hypervisor. If
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* the pending datagram is not from hypervisor, then we check
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* if enqueueing it would exceed the
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* VMCI_MAX_DATAGRAM_QUEUE_SIZE limit on the destination. If
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* the pending datagram is from hypervisor, we allow it to be
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* queued at the destination side provided we don't reach the
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* VMCI_MAX_DATAGRAM_AND_EVENT_QUEUE_SIZE limit.
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*/
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if (context->datagram_queue_size + vmci_dg_size >=
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VMCI_MAX_DATAGRAM_QUEUE_SIZE &&
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(!vmci_handle_is_equal(dg_src,
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vmci_make_handle
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(VMCI_HYPERVISOR_CONTEXT_ID,
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VMCI_CONTEXT_RESOURCE_ID)) ||
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context->datagram_queue_size + vmci_dg_size >=
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VMCI_MAX_DATAGRAM_AND_EVENT_QUEUE_SIZE)) {
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spin_unlock(&context->lock);
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vmci_ctx_put(context);
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kfree(dq_entry);
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pr_devel("Context (ID=0x%x) receive queue is full\n", cid);
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return VMCI_ERROR_NO_RESOURCES;
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}
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list_add(&dq_entry->list_item, &context->datagram_queue);
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context->pending_datagrams++;
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context->datagram_queue_size += vmci_dg_size;
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ctx_signal_notify(context);
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wake_up(&context->host_context.wait_queue);
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spin_unlock(&context->lock);
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vmci_ctx_put(context);
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return vmci_dg_size;
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}
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/*
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* Verifies whether a context with the specified context ID exists.
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* FIXME: utility is dubious as no decisions can be reliably made
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* using this data as context can appear and disappear at any time.
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*/
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bool vmci_ctx_exists(u32 cid)
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{
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struct vmci_ctx *context;
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bool exists = false;
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rcu_read_lock();
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list_for_each_entry_rcu(context, &ctx_list.head, list_item) {
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if (context->cid == cid) {
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exists = true;
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break;
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}
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}
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rcu_read_unlock();
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return exists;
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}
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/*
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* Retrieves VMCI context corresponding to the given cid.
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*/
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struct vmci_ctx *vmci_ctx_get(u32 cid)
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{
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struct vmci_ctx *c, *context = NULL;
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if (cid == VMCI_INVALID_ID)
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return NULL;
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rcu_read_lock();
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list_for_each_entry_rcu(c, &ctx_list.head, list_item) {
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if (c->cid == cid) {
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/*
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* The context owner drops its own reference to the
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* context only after removing it from the list and
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* waiting for RCU grace period to expire. This
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* means that we are not about to increase the
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* reference count of something that is in the
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* process of being destroyed.
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*/
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context = c;
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kref_get(&context->kref);
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break;
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}
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}
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rcu_read_unlock();
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return context;
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}
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/*
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* Deallocates all parts of a context data structure. This
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* function doesn't lock the context, because it assumes that
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* the caller was holding the last reference to context.
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*/
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static void ctx_free_ctx(struct kref *kref)
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{
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struct vmci_ctx *context = container_of(kref, struct vmci_ctx, kref);
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struct vmci_datagram_queue_entry *dq_entry, *dq_entry_tmp;
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struct vmci_handle temp_handle;
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struct vmci_handle_list *notifier, *tmp;
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/*
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* Fire event to all contexts interested in knowing this
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* context is dying.
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*/
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ctx_fire_notification(context->cid, context->priv_flags);
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/*
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* Cleanup all queue pair resources attached to context. If
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* the VM dies without cleaning up, this code will make sure
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* that no resources are leaked.
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*/
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temp_handle = vmci_handle_arr_get_entry(context->queue_pair_array, 0);
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while (!vmci_handle_is_equal(temp_handle, VMCI_INVALID_HANDLE)) {
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if (vmci_qp_broker_detach(temp_handle,
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context) < VMCI_SUCCESS) {
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/*
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* When vmci_qp_broker_detach() succeeds it
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* removes the handle from the array. If
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* detach fails, we must remove the handle
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* ourselves.
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*/
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vmci_handle_arr_remove_entry(context->queue_pair_array,
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temp_handle);
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}
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temp_handle =
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vmci_handle_arr_get_entry(context->queue_pair_array, 0);
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}
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/*
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* It is fine to destroy this without locking the callQueue, as
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* this is the only thread having a reference to the context.
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*/
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list_for_each_entry_safe(dq_entry, dq_entry_tmp,
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&context->datagram_queue, list_item) {
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WARN_ON(dq_entry->dg_size != VMCI_DG_SIZE(dq_entry->dg));
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list_del(&dq_entry->list_item);
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kfree(dq_entry->dg);
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kfree(dq_entry);
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}
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list_for_each_entry_safe(notifier, tmp,
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&context->notifier_list, node) {
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list_del(¬ifier->node);
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kfree(notifier);
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}
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vmci_handle_arr_destroy(context->queue_pair_array);
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vmci_handle_arr_destroy(context->doorbell_array);
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vmci_handle_arr_destroy(context->pending_doorbell_array);
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vmci_ctx_unset_notify(context);
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if (context->cred)
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put_cred(context->cred);
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kfree(context);
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}
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/*
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* Drops reference to VMCI context. If this is the last reference to
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* the context it will be deallocated. A context is created with
|
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* a reference count of one, and on destroy, it is removed from
|
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* the context list before its reference count is decremented. Thus,
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* if we reach zero, we are sure that nobody else are about to increment
|
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* it (they need the entry in the context list for that), and so there
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* is no need for locking.
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*/
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void vmci_ctx_put(struct vmci_ctx *context)
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{
|
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kref_put(&context->kref, ctx_free_ctx);
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}
|
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|
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/*
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* Dequeues the next datagram and returns it to caller.
|
|
* The caller passes in a pointer to the max size datagram
|
|
* it can handle and the datagram is only unqueued if the
|
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* size is less than max_size. If larger max_size is set to
|
|
* the size of the datagram to give the caller a chance to
|
|
* set up a larger buffer for the guestcall.
|
|
*/
|
|
int vmci_ctx_dequeue_datagram(struct vmci_ctx *context,
|
|
size_t *max_size,
|
|
struct vmci_datagram **dg)
|
|
{
|
|
struct vmci_datagram_queue_entry *dq_entry;
|
|
struct list_head *list_item;
|
|
int rv;
|
|
|
|
/* Dequeue the next datagram entry. */
|
|
spin_lock(&context->lock);
|
|
if (context->pending_datagrams == 0) {
|
|
ctx_clear_notify_call(context);
|
|
spin_unlock(&context->lock);
|
|
pr_devel("No datagrams pending\n");
|
|
return VMCI_ERROR_NO_MORE_DATAGRAMS;
|
|
}
|
|
|
|
list_item = context->datagram_queue.next;
|
|
|
|
dq_entry =
|
|
list_entry(list_item, struct vmci_datagram_queue_entry, list_item);
|
|
|
|
/* Check size of caller's buffer. */
|
|
if (*max_size < dq_entry->dg_size) {
|
|
*max_size = dq_entry->dg_size;
|
|
spin_unlock(&context->lock);
|
|
pr_devel("Caller's buffer should be at least (size=%u bytes)\n",
|
|
(u32) *max_size);
|
|
return VMCI_ERROR_NO_MEM;
|
|
}
|
|
|
|
list_del(list_item);
|
|
context->pending_datagrams--;
|
|
context->datagram_queue_size -= dq_entry->dg_size;
|
|
if (context->pending_datagrams == 0) {
|
|
ctx_clear_notify_call(context);
|
|
rv = VMCI_SUCCESS;
|
|
} else {
|
|
/*
|
|
* Return the size of the next datagram.
|
|
*/
|
|
struct vmci_datagram_queue_entry *next_entry;
|
|
|
|
list_item = context->datagram_queue.next;
|
|
next_entry =
|
|
list_entry(list_item, struct vmci_datagram_queue_entry,
|
|
list_item);
|
|
|
|
/*
|
|
* The following size_t -> int truncation is fine as
|
|
* the maximum size of a (routable) datagram is 68KB.
|
|
*/
|
|
rv = (int)next_entry->dg_size;
|
|
}
|
|
spin_unlock(&context->lock);
|
|
|
|
/* Caller must free datagram. */
|
|
*dg = dq_entry->dg;
|
|
dq_entry->dg = NULL;
|
|
kfree(dq_entry);
|
|
|
|
return rv;
|
|
}
|
|
|
|
/*
|
|
* Reverts actions set up by vmci_setup_notify(). Unmaps and unlocks the
|
|
* page mapped/locked by vmci_setup_notify().
|
|
*/
|
|
void vmci_ctx_unset_notify(struct vmci_ctx *context)
|
|
{
|
|
struct page *notify_page;
|
|
|
|
spin_lock(&context->lock);
|
|
|
|
notify_page = context->notify_page;
|
|
context->notify = &ctx_dummy_notify;
|
|
context->notify_page = NULL;
|
|
|
|
spin_unlock(&context->lock);
|
|
|
|
if (notify_page) {
|
|
kunmap(notify_page);
|
|
put_page(notify_page);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Add remote_cid to list of contexts current contexts wants
|
|
* notifications from/about.
|
|
*/
|
|
int vmci_ctx_add_notification(u32 context_id, u32 remote_cid)
|
|
{
|
|
struct vmci_ctx *context;
|
|
struct vmci_handle_list *notifier, *n;
|
|
int result;
|
|
bool exists = false;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (!context)
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
|
|
if (VMCI_CONTEXT_IS_VM(context_id) && VMCI_CONTEXT_IS_VM(remote_cid)) {
|
|
pr_devel("Context removed notifications for other VMs not supported (src=0x%x, remote=0x%x)\n",
|
|
context_id, remote_cid);
|
|
result = VMCI_ERROR_DST_UNREACHABLE;
|
|
goto out;
|
|
}
|
|
|
|
if (context->priv_flags & VMCI_PRIVILEGE_FLAG_RESTRICTED) {
|
|
result = VMCI_ERROR_NO_ACCESS;
|
|
goto out;
|
|
}
|
|
|
|
notifier = kmalloc(sizeof(struct vmci_handle_list), GFP_KERNEL);
|
|
if (!notifier) {
|
|
result = VMCI_ERROR_NO_MEM;
|
|
goto out;
|
|
}
|
|
|
|
INIT_LIST_HEAD(¬ifier->node);
|
|
notifier->handle = vmci_make_handle(remote_cid, VMCI_EVENT_HANDLER);
|
|
|
|
spin_lock(&context->lock);
|
|
|
|
list_for_each_entry(n, &context->notifier_list, node) {
|
|
if (vmci_handle_is_equal(n->handle, notifier->handle)) {
|
|
exists = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (exists) {
|
|
kfree(notifier);
|
|
result = VMCI_ERROR_ALREADY_EXISTS;
|
|
} else {
|
|
list_add_tail_rcu(¬ifier->node, &context->notifier_list);
|
|
context->n_notifiers++;
|
|
result = VMCI_SUCCESS;
|
|
}
|
|
|
|
spin_unlock(&context->lock);
|
|
|
|
out:
|
|
vmci_ctx_put(context);
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Remove remote_cid from current context's list of contexts it is
|
|
* interested in getting notifications from/about.
|
|
*/
|
|
int vmci_ctx_remove_notification(u32 context_id, u32 remote_cid)
|
|
{
|
|
struct vmci_ctx *context;
|
|
struct vmci_handle_list *notifier, *tmp;
|
|
struct vmci_handle handle;
|
|
bool found = false;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (!context)
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
|
|
handle = vmci_make_handle(remote_cid, VMCI_EVENT_HANDLER);
|
|
|
|
spin_lock(&context->lock);
|
|
list_for_each_entry_safe(notifier, tmp,
|
|
&context->notifier_list, node) {
|
|
if (vmci_handle_is_equal(notifier->handle, handle)) {
|
|
list_del_rcu(¬ifier->node);
|
|
context->n_notifiers--;
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock(&context->lock);
|
|
|
|
if (found) {
|
|
synchronize_rcu();
|
|
kfree(notifier);
|
|
}
|
|
|
|
vmci_ctx_put(context);
|
|
|
|
return found ? VMCI_SUCCESS : VMCI_ERROR_NOT_FOUND;
|
|
}
|
|
|
|
static int vmci_ctx_get_chkpt_notifiers(struct vmci_ctx *context,
|
|
u32 *buf_size, void **pbuf)
|
|
{
|
|
u32 *notifiers;
|
|
size_t data_size;
|
|
struct vmci_handle_list *entry;
|
|
int i = 0;
|
|
|
|
if (context->n_notifiers == 0) {
|
|
*buf_size = 0;
|
|
*pbuf = NULL;
|
|
return VMCI_SUCCESS;
|
|
}
|
|
|
|
data_size = context->n_notifiers * sizeof(*notifiers);
|
|
if (*buf_size < data_size) {
|
|
*buf_size = data_size;
|
|
return VMCI_ERROR_MORE_DATA;
|
|
}
|
|
|
|
notifiers = kmalloc(data_size, GFP_ATOMIC); /* FIXME: want GFP_KERNEL */
|
|
if (!notifiers)
|
|
return VMCI_ERROR_NO_MEM;
|
|
|
|
list_for_each_entry(entry, &context->notifier_list, node)
|
|
notifiers[i++] = entry->handle.context;
|
|
|
|
*buf_size = data_size;
|
|
*pbuf = notifiers;
|
|
return VMCI_SUCCESS;
|
|
}
|
|
|
|
static int vmci_ctx_get_chkpt_doorbells(struct vmci_ctx *context,
|
|
u32 *buf_size, void **pbuf)
|
|
{
|
|
struct dbell_cpt_state *dbells;
|
|
size_t n_doorbells;
|
|
int i;
|
|
|
|
n_doorbells = vmci_handle_arr_get_size(context->doorbell_array);
|
|
if (n_doorbells > 0) {
|
|
size_t data_size = n_doorbells * sizeof(*dbells);
|
|
if (*buf_size < data_size) {
|
|
*buf_size = data_size;
|
|
return VMCI_ERROR_MORE_DATA;
|
|
}
|
|
|
|
dbells = kmalloc(data_size, GFP_ATOMIC);
|
|
if (!dbells)
|
|
return VMCI_ERROR_NO_MEM;
|
|
|
|
for (i = 0; i < n_doorbells; i++)
|
|
dbells[i].handle = vmci_handle_arr_get_entry(
|
|
context->doorbell_array, i);
|
|
|
|
*buf_size = data_size;
|
|
*pbuf = dbells;
|
|
} else {
|
|
*buf_size = 0;
|
|
*pbuf = NULL;
|
|
}
|
|
|
|
return VMCI_SUCCESS;
|
|
}
|
|
|
|
/*
|
|
* Get current context's checkpoint state of given type.
|
|
*/
|
|
int vmci_ctx_get_chkpt_state(u32 context_id,
|
|
u32 cpt_type,
|
|
u32 *buf_size,
|
|
void **pbuf)
|
|
{
|
|
struct vmci_ctx *context;
|
|
int result;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (!context)
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
|
|
spin_lock(&context->lock);
|
|
|
|
switch (cpt_type) {
|
|
case VMCI_NOTIFICATION_CPT_STATE:
|
|
result = vmci_ctx_get_chkpt_notifiers(context, buf_size, pbuf);
|
|
break;
|
|
|
|
case VMCI_WELLKNOWN_CPT_STATE:
|
|
/*
|
|
* For compatibility with VMX'en with VM to VM communication, we
|
|
* always return zero wellknown handles.
|
|
*/
|
|
|
|
*buf_size = 0;
|
|
*pbuf = NULL;
|
|
result = VMCI_SUCCESS;
|
|
break;
|
|
|
|
case VMCI_DOORBELL_CPT_STATE:
|
|
result = vmci_ctx_get_chkpt_doorbells(context, buf_size, pbuf);
|
|
break;
|
|
|
|
default:
|
|
pr_devel("Invalid cpt state (type=%d)\n", cpt_type);
|
|
result = VMCI_ERROR_INVALID_ARGS;
|
|
break;
|
|
}
|
|
|
|
spin_unlock(&context->lock);
|
|
vmci_ctx_put(context);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Set current context's checkpoint state of given type.
|
|
*/
|
|
int vmci_ctx_set_chkpt_state(u32 context_id,
|
|
u32 cpt_type,
|
|
u32 buf_size,
|
|
void *cpt_buf)
|
|
{
|
|
u32 i;
|
|
u32 current_id;
|
|
int result = VMCI_SUCCESS;
|
|
u32 num_ids = buf_size / sizeof(u32);
|
|
|
|
if (cpt_type == VMCI_WELLKNOWN_CPT_STATE && num_ids > 0) {
|
|
/*
|
|
* We would end up here if VMX with VM to VM communication
|
|
* attempts to restore a checkpoint with wellknown handles.
|
|
*/
|
|
pr_warn("Attempt to restore checkpoint with obsolete wellknown handles\n");
|
|
return VMCI_ERROR_OBSOLETE;
|
|
}
|
|
|
|
if (cpt_type != VMCI_NOTIFICATION_CPT_STATE) {
|
|
pr_devel("Invalid cpt state (type=%d)\n", cpt_type);
|
|
return VMCI_ERROR_INVALID_ARGS;
|
|
}
|
|
|
|
for (i = 0; i < num_ids && result == VMCI_SUCCESS; i++) {
|
|
current_id = ((u32 *)cpt_buf)[i];
|
|
result = vmci_ctx_add_notification(context_id, current_id);
|
|
if (result != VMCI_SUCCESS)
|
|
break;
|
|
}
|
|
if (result != VMCI_SUCCESS)
|
|
pr_devel("Failed to set cpt state (type=%d) (error=%d)\n",
|
|
cpt_type, result);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Retrieves the specified context's pending notifications in the
|
|
* form of a handle array. The handle arrays returned are the
|
|
* actual data - not a copy and should not be modified by the
|
|
* caller. They must be released using
|
|
* vmci_ctx_rcv_notifications_release.
|
|
*/
|
|
int vmci_ctx_rcv_notifications_get(u32 context_id,
|
|
struct vmci_handle_arr **db_handle_array,
|
|
struct vmci_handle_arr **qp_handle_array)
|
|
{
|
|
struct vmci_ctx *context;
|
|
int result = VMCI_SUCCESS;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (context == NULL)
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
|
|
spin_lock(&context->lock);
|
|
|
|
*db_handle_array = context->pending_doorbell_array;
|
|
context->pending_doorbell_array = vmci_handle_arr_create(0);
|
|
if (!context->pending_doorbell_array) {
|
|
context->pending_doorbell_array = *db_handle_array;
|
|
*db_handle_array = NULL;
|
|
result = VMCI_ERROR_NO_MEM;
|
|
}
|
|
*qp_handle_array = NULL;
|
|
|
|
spin_unlock(&context->lock);
|
|
vmci_ctx_put(context);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Releases handle arrays with pending notifications previously
|
|
* retrieved using vmci_ctx_rcv_notifications_get. If the
|
|
* notifications were not successfully handed over to the guest,
|
|
* success must be false.
|
|
*/
|
|
void vmci_ctx_rcv_notifications_release(u32 context_id,
|
|
struct vmci_handle_arr *db_handle_array,
|
|
struct vmci_handle_arr *qp_handle_array,
|
|
bool success)
|
|
{
|
|
struct vmci_ctx *context = vmci_ctx_get(context_id);
|
|
|
|
spin_lock(&context->lock);
|
|
if (!success) {
|
|
struct vmci_handle handle;
|
|
|
|
/*
|
|
* New notifications may have been added while we were not
|
|
* holding the context lock, so we transfer any new pending
|
|
* doorbell notifications to the old array, and reinstate the
|
|
* old array.
|
|
*/
|
|
|
|
handle = vmci_handle_arr_remove_tail(
|
|
context->pending_doorbell_array);
|
|
while (!vmci_handle_is_invalid(handle)) {
|
|
if (!vmci_handle_arr_has_entry(db_handle_array,
|
|
handle)) {
|
|
vmci_handle_arr_append_entry(
|
|
&db_handle_array, handle);
|
|
}
|
|
handle = vmci_handle_arr_remove_tail(
|
|
context->pending_doorbell_array);
|
|
}
|
|
vmci_handle_arr_destroy(context->pending_doorbell_array);
|
|
context->pending_doorbell_array = db_handle_array;
|
|
db_handle_array = NULL;
|
|
} else {
|
|
ctx_clear_notify_call(context);
|
|
}
|
|
spin_unlock(&context->lock);
|
|
vmci_ctx_put(context);
|
|
|
|
if (db_handle_array)
|
|
vmci_handle_arr_destroy(db_handle_array);
|
|
|
|
if (qp_handle_array)
|
|
vmci_handle_arr_destroy(qp_handle_array);
|
|
}
|
|
|
|
/*
|
|
* Registers that a new doorbell handle has been allocated by the
|
|
* context. Only doorbell handles registered can be notified.
|
|
*/
|
|
int vmci_ctx_dbell_create(u32 context_id, struct vmci_handle handle)
|
|
{
|
|
struct vmci_ctx *context;
|
|
int result;
|
|
|
|
if (context_id == VMCI_INVALID_ID || vmci_handle_is_invalid(handle))
|
|
return VMCI_ERROR_INVALID_ARGS;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (context == NULL)
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
|
|
spin_lock(&context->lock);
|
|
if (!vmci_handle_arr_has_entry(context->doorbell_array, handle)) {
|
|
vmci_handle_arr_append_entry(&context->doorbell_array, handle);
|
|
result = VMCI_SUCCESS;
|
|
} else {
|
|
result = VMCI_ERROR_DUPLICATE_ENTRY;
|
|
}
|
|
|
|
spin_unlock(&context->lock);
|
|
vmci_ctx_put(context);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Unregisters a doorbell handle that was previously registered
|
|
* with vmci_ctx_dbell_create.
|
|
*/
|
|
int vmci_ctx_dbell_destroy(u32 context_id, struct vmci_handle handle)
|
|
{
|
|
struct vmci_ctx *context;
|
|
struct vmci_handle removed_handle;
|
|
|
|
if (context_id == VMCI_INVALID_ID || vmci_handle_is_invalid(handle))
|
|
return VMCI_ERROR_INVALID_ARGS;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (context == NULL)
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
|
|
spin_lock(&context->lock);
|
|
removed_handle =
|
|
vmci_handle_arr_remove_entry(context->doorbell_array, handle);
|
|
vmci_handle_arr_remove_entry(context->pending_doorbell_array, handle);
|
|
spin_unlock(&context->lock);
|
|
|
|
vmci_ctx_put(context);
|
|
|
|
return vmci_handle_is_invalid(removed_handle) ?
|
|
VMCI_ERROR_NOT_FOUND : VMCI_SUCCESS;
|
|
}
|
|
|
|
/*
|
|
* Unregisters all doorbell handles that were previously
|
|
* registered with vmci_ctx_dbell_create.
|
|
*/
|
|
int vmci_ctx_dbell_destroy_all(u32 context_id)
|
|
{
|
|
struct vmci_ctx *context;
|
|
struct vmci_handle handle;
|
|
|
|
if (context_id == VMCI_INVALID_ID)
|
|
return VMCI_ERROR_INVALID_ARGS;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (context == NULL)
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
|
|
spin_lock(&context->lock);
|
|
do {
|
|
struct vmci_handle_arr *arr = context->doorbell_array;
|
|
handle = vmci_handle_arr_remove_tail(arr);
|
|
} while (!vmci_handle_is_invalid(handle));
|
|
do {
|
|
struct vmci_handle_arr *arr = context->pending_doorbell_array;
|
|
handle = vmci_handle_arr_remove_tail(arr);
|
|
} while (!vmci_handle_is_invalid(handle));
|
|
spin_unlock(&context->lock);
|
|
|
|
vmci_ctx_put(context);
|
|
|
|
return VMCI_SUCCESS;
|
|
}
|
|
|
|
/*
|
|
* Registers a notification of a doorbell handle initiated by the
|
|
* specified source context. The notification of doorbells are
|
|
* subject to the same isolation rules as datagram delivery. To
|
|
* allow host side senders of notifications a finer granularity
|
|
* of sender rights than those assigned to the sending context
|
|
* itself, the host context is required to specify a different
|
|
* set of privilege flags that will override the privileges of
|
|
* the source context.
|
|
*/
|
|
int vmci_ctx_notify_dbell(u32 src_cid,
|
|
struct vmci_handle handle,
|
|
u32 src_priv_flags)
|
|
{
|
|
struct vmci_ctx *dst_context;
|
|
int result;
|
|
|
|
if (vmci_handle_is_invalid(handle))
|
|
return VMCI_ERROR_INVALID_ARGS;
|
|
|
|
/* Get the target VM's VMCI context. */
|
|
dst_context = vmci_ctx_get(handle.context);
|
|
if (!dst_context) {
|
|
pr_devel("Invalid context (ID=0x%x)\n", handle.context);
|
|
return VMCI_ERROR_NOT_FOUND;
|
|
}
|
|
|
|
if (src_cid != handle.context) {
|
|
u32 dst_priv_flags;
|
|
|
|
if (VMCI_CONTEXT_IS_VM(src_cid) &&
|
|
VMCI_CONTEXT_IS_VM(handle.context)) {
|
|
pr_devel("Doorbell notification from VM to VM not supported (src=0x%x, dst=0x%x)\n",
|
|
src_cid, handle.context);
|
|
result = VMCI_ERROR_DST_UNREACHABLE;
|
|
goto out;
|
|
}
|
|
|
|
result = vmci_dbell_get_priv_flags(handle, &dst_priv_flags);
|
|
if (result < VMCI_SUCCESS) {
|
|
pr_warn("Failed to get privilege flags for destination (handle=0x%x:0x%x)\n",
|
|
handle.context, handle.resource);
|
|
goto out;
|
|
}
|
|
|
|
if (src_cid != VMCI_HOST_CONTEXT_ID ||
|
|
src_priv_flags == VMCI_NO_PRIVILEGE_FLAGS) {
|
|
src_priv_flags = vmci_context_get_priv_flags(src_cid);
|
|
}
|
|
|
|
if (vmci_deny_interaction(src_priv_flags, dst_priv_flags)) {
|
|
result = VMCI_ERROR_NO_ACCESS;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (handle.context == VMCI_HOST_CONTEXT_ID) {
|
|
result = vmci_dbell_host_context_notify(src_cid, handle);
|
|
} else {
|
|
spin_lock(&dst_context->lock);
|
|
|
|
if (!vmci_handle_arr_has_entry(dst_context->doorbell_array,
|
|
handle)) {
|
|
result = VMCI_ERROR_NOT_FOUND;
|
|
} else {
|
|
if (!vmci_handle_arr_has_entry(
|
|
dst_context->pending_doorbell_array,
|
|
handle)) {
|
|
vmci_handle_arr_append_entry(
|
|
&dst_context->pending_doorbell_array,
|
|
handle);
|
|
|
|
ctx_signal_notify(dst_context);
|
|
wake_up(&dst_context->host_context.wait_queue);
|
|
|
|
}
|
|
result = VMCI_SUCCESS;
|
|
}
|
|
spin_unlock(&dst_context->lock);
|
|
}
|
|
|
|
out:
|
|
vmci_ctx_put(dst_context);
|
|
|
|
return result;
|
|
}
|
|
|
|
bool vmci_ctx_supports_host_qp(struct vmci_ctx *context)
|
|
{
|
|
return context && context->user_version >= VMCI_VERSION_HOSTQP;
|
|
}
|
|
|
|
/*
|
|
* Registers that a new queue pair handle has been allocated by
|
|
* the context.
|
|
*/
|
|
int vmci_ctx_qp_create(struct vmci_ctx *context, struct vmci_handle handle)
|
|
{
|
|
int result;
|
|
|
|
if (context == NULL || vmci_handle_is_invalid(handle))
|
|
return VMCI_ERROR_INVALID_ARGS;
|
|
|
|
if (!vmci_handle_arr_has_entry(context->queue_pair_array, handle)) {
|
|
vmci_handle_arr_append_entry(&context->queue_pair_array,
|
|
handle);
|
|
result = VMCI_SUCCESS;
|
|
} else {
|
|
result = VMCI_ERROR_DUPLICATE_ENTRY;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Unregisters a queue pair handle that was previously registered
|
|
* with vmci_ctx_qp_create.
|
|
*/
|
|
int vmci_ctx_qp_destroy(struct vmci_ctx *context, struct vmci_handle handle)
|
|
{
|
|
struct vmci_handle hndl;
|
|
|
|
if (context == NULL || vmci_handle_is_invalid(handle))
|
|
return VMCI_ERROR_INVALID_ARGS;
|
|
|
|
hndl = vmci_handle_arr_remove_entry(context->queue_pair_array, handle);
|
|
|
|
return vmci_handle_is_invalid(hndl) ?
|
|
VMCI_ERROR_NOT_FOUND : VMCI_SUCCESS;
|
|
}
|
|
|
|
/*
|
|
* Determines whether a given queue pair handle is registered
|
|
* with the given context.
|
|
*/
|
|
bool vmci_ctx_qp_exists(struct vmci_ctx *context, struct vmci_handle handle)
|
|
{
|
|
if (context == NULL || vmci_handle_is_invalid(handle))
|
|
return false;
|
|
|
|
return vmci_handle_arr_has_entry(context->queue_pair_array, handle);
|
|
}
|
|
|
|
/*
|
|
* vmci_context_get_priv_flags() - Retrieve privilege flags.
|
|
* @context_id: The context ID of the VMCI context.
|
|
*
|
|
* Retrieves privilege flags of the given VMCI context ID.
|
|
*/
|
|
u32 vmci_context_get_priv_flags(u32 context_id)
|
|
{
|
|
if (vmci_host_code_active()) {
|
|
u32 flags;
|
|
struct vmci_ctx *context;
|
|
|
|
context = vmci_ctx_get(context_id);
|
|
if (!context)
|
|
return VMCI_LEAST_PRIVILEGE_FLAGS;
|
|
|
|
flags = context->priv_flags;
|
|
vmci_ctx_put(context);
|
|
return flags;
|
|
}
|
|
return VMCI_NO_PRIVILEGE_FLAGS;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmci_context_get_priv_flags);
|
|
|
|
/*
|
|
* vmci_is_context_owner() - Determimnes if user is the context owner
|
|
* @context_id: The context ID of the VMCI context.
|
|
* @uid: The host user id (real kernel value).
|
|
*
|
|
* Determines whether a given UID is the owner of given VMCI context.
|
|
*/
|
|
bool vmci_is_context_owner(u32 context_id, kuid_t uid)
|
|
{
|
|
bool is_owner = false;
|
|
|
|
if (vmci_host_code_active()) {
|
|
struct vmci_ctx *context = vmci_ctx_get(context_id);
|
|
if (context) {
|
|
if (context->cred)
|
|
is_owner = uid_eq(context->cred->uid, uid);
|
|
vmci_ctx_put(context);
|
|
}
|
|
}
|
|
|
|
return is_owner;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmci_is_context_owner);
|