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1217 lines
31 KiB
1217 lines
31 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
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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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#include <linux/vmw_vmci_defs.h> |
|
#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/cred.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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/* Use a wide upper bound for the maximum contexts. */ |
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#define VMCI_MAX_CONTEXTS 2000 |
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|
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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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|
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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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|
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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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/* |
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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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/* |
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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context->queue_pair_array = |
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vmci_handle_arr_create(0, VMCI_MAX_GUEST_QP_COUNT); |
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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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|
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context->doorbell_array = |
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vmci_handle_arr_create(0, VMCI_MAX_GUEST_DOORBELL_COUNT); |
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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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|
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context->pending_doorbell_array = |
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vmci_handle_arr_create(0, VMCI_MAX_GUEST_DOORBELL_COUNT); |
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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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|
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context->user_version = user_version; |
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|
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context->priv_flags = priv_flags; |
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|
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if (cred) |
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context->cred = get_cred(cred); |
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|
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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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/* |
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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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|
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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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|
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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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/* |
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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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|
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vmci_ctx_put(context); |
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} |
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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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/* |
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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, VMCI_MAX_CONTEXTS); |
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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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/* |
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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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/* |
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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return VMCI_SUCCESS; |
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} |
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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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|
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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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|
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return VMCI_SUCCESS; |
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} |
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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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|
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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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|
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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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|
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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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|
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spin_lock(&context->lock); |
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|
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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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|
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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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|
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rcu_read_lock(); |
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|
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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 |
|
* the caller was holding the last reference to context. |
|
*/ |
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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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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 |
|
* 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); |
|
while (!vmci_handle_is_equal(temp_handle, VMCI_INVALID_HANDLE)) { |
|
if (vmci_qp_broker_detach(temp_handle, |
|
context) < VMCI_SUCCESS) { |
|
/* |
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* When vmci_qp_broker_detach() succeeds it |
|
* removes the handle from the array. If |
|
* 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, |
|
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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* It is fine to destroy this without locking the callQueue, as |
|
* this is the only thread having a reference to the context. |
|
*/ |
|
list_for_each_entry_safe(dq_entry, dq_entry_tmp, |
|
&context->datagram_queue, list_item) { |
|
WARN_ON(dq_entry->dg_size != VMCI_DG_SIZE(dq_entry->dg)); |
|
list_del(&dq_entry->list_item); |
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kfree(dq_entry->dg); |
|
kfree(dq_entry); |
|
} |
|
|
|
list_for_each_entry_safe(notifier, tmp, |
|
&context->notifier_list, node) { |
|
list_del(¬ifier->node); |
|
kfree(notifier); |
|
} |
|
|
|
vmci_handle_arr_destroy(context->queue_pair_array); |
|
vmci_handle_arr_destroy(context->doorbell_array); |
|
vmci_handle_arr_destroy(context->pending_doorbell_array); |
|
vmci_ctx_unset_notify(context); |
|
if (context->cred) |
|
put_cred(context->cred); |
|
kfree(context); |
|
} |
|
|
|
/* |
|
* Drops reference to VMCI context. If this is the last reference to |
|
* the context it will be deallocated. A context is created with |
|
* a reference count of one, and on destroy, it is removed from |
|
* the context list before its reference count is decremented. Thus, |
|
* if we reach zero, we are sure that nobody else are about to increment |
|
* it (they need the entry in the context list for that), and so there |
|
* is no need for locking. |
|
*/ |
|
void vmci_ctx_put(struct vmci_ctx *context) |
|
{ |
|
kref_put(&context->kref, ctx_free_ctx); |
|
} |
|
|
|
/* |
|
* 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 |
|
* 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); |
|
|
|
if (context->n_notifiers < VMCI_MAX_CONTEXTS) { |
|
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; |
|
} |
|
} else { |
|
kfree(notifier); |
|
result = VMCI_ERROR_NO_MEM; |
|
} |
|
|
|
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; |
|
u32 i, n_doorbells; |
|
|
|
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 = kzalloc(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, VMCI_MAX_GUEST_DOORBELL_COUNT); |
|
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)) |
|
result = vmci_handle_arr_append_entry(&context->doorbell_array, |
|
handle); |
|
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)) { |
|
result = vmci_handle_arr_append_entry( |
|
&dst_context->pending_doorbell_array, |
|
handle); |
|
if (result == VMCI_SUCCESS) { |
|
ctx_signal_notify(dst_context); |
|
wake_up(&dst_context->host_context.wait_queue); |
|
} |
|
} else { |
|
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)) |
|
result = vmci_handle_arr_append_entry( |
|
&context->queue_pair_array, handle); |
|
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. |
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*/ |
|
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);
|
|
|