drivers/misc/vmw_vmci/vmci_driver.c

   1 /*
   2  * VMware VMCI Driver
   3  *
   4  * Copyright (C) 2012 VMware, Inc. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation version 2 and no later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  */
  15
  16 #include <linux/vmw_vmci_defs.h>
  17 #include <linux/vmw_vmci_api.h>
  18 #include <linux/atomic.h>
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/init.h>
  22
  23 #include "vmci_driver.h"
  24 #include "vmci_event.h"
  25
  26 static bool vmci_disable_host;
  27 module_param_named(disable_host, vmci_disable_host, bool, 0);
  28 MODULE_PARM_DESC(disable_host,
  29                  "Disable driver host personality (default=enabled)");
  30
  31 static bool vmci_disable_guest;
  32 module_param_named(disable_guest, vmci_disable_guest, bool, 0);
  33 MODULE_PARM_DESC(disable_guest,
  34                  "Disable driver guest personality (default=enabled)");
  35
  36 static bool vmci_guest_personality_initialized;
  37 static bool vmci_host_personality_initialized;
  38
  39 /*
  40  * vmci_get_context_id() - Gets the current context ID.
  41  *
  42  * Returns the current context ID.  Note that since this is accessed only
  43  * from code running in the host, this always returns the host context ID.
  44  */
  45 u32 vmci_get_context_id(void)
  46 {
  47         if (vmci_guest_code_active())
  48                 return vmci_get_vm_context_id();
  49         else if (vmci_host_code_active())
  50                 return VMCI_HOST_CONTEXT_ID;
  51
  52         return VMCI_INVALID_ID;
  53 }
  54 EXPORT_SYMBOL_GPL(vmci_get_context_id);
  55
  56 static int __init vmci_drv_init(void)
  57 {
  58         int vmci_err;
  59         int error;
  60
  61         vmci_err = vmci_event_init();
  62         if (vmci_err < VMCI_SUCCESS) {
  63                 pr_err("Failed to initialize VMCIEvent (result=%d)\n",
  64                        vmci_err);
  65                 return -EINVAL;
  66         }
  67
  68         if (!vmci_disable_guest) {
  69                 error = vmci_guest_init();
  70                 if (error) {
  71                         pr_warn("Failed to initialize guest personality (err=%d)\n",
  72                                 error);
  73                 } else {
  74                         vmci_guest_personality_initialized = true;
  75                         pr_info("Guest personality initialized and is %s\n",
  76                                 vmci_guest_code_active() ?
  77                                 "active" : "inactive");
  78                 }
  79         }
  80
  81         if (!vmci_disable_host) {
  82                 error = vmci_host_init();
  83                 if (error) {
  84                         pr_warn("Unable to initialize host personality (err=%d)\n",
  85                                 error);
  86                 } else {
  87                         vmci_host_personality_initialized = true;
  88                         pr_info("Initialized host personality\n");
  89                 }
  90         }
  91
  92         if (!vmci_guest_personality_initialized &&
  93             !vmci_host_personality_initialized) {
  94                 vmci_event_exit();
  95                 return -ENODEV;
  96         }
  97
  98         return 0;
  99 }
 100 module_init(vmci_drv_init);
 101
 102 static void __exit vmci_drv_exit(void)
 103 {
 104         if (vmci_guest_personality_initialized)
 105                 vmci_guest_exit();
 106
 107         if (vmci_host_personality_initialized)
 108                 vmci_host_exit();
 109
 110         vmci_event_exit();
 111 }
 112 module_exit(vmci_drv_exit);
 113
 114 MODULE_AUTHOR("VMware, Inc.");
 115 MODULE_DESCRIPTION("VMware Virtual Machine Communication Interface.");
 116 MODULE_VERSION("1.1.0.0-k");
 117 MODULE_LICENSE("GPL v2");