brintos

brintos / linux-shallow public Read only

0
0
Text · 4.1 KiB · cbb706d Raw
177 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * VMware VMCI Driver4 *5 * Copyright (C) 2012 VMware, Inc. All rights reserved.6 */7 8#include <linux/vmw_vmci_defs.h>9#include <linux/vmw_vmci_api.h>10#include <linux/atomic.h>11#include <linux/kernel.h>12#include <linux/module.h>13#include <linux/init.h>14 15#include "vmci_driver.h"16#include "vmci_event.h"17 18static bool vmci_disable_host;19module_param_named(disable_host, vmci_disable_host, bool, 0);20MODULE_PARM_DESC(disable_host,21		 "Disable driver host personality (default=enabled)");22 23static bool vmci_disable_guest;24module_param_named(disable_guest, vmci_disable_guest, bool, 0);25MODULE_PARM_DESC(disable_guest,26		 "Disable driver guest personality (default=enabled)");27 28static bool vmci_guest_personality_initialized;29static bool vmci_host_personality_initialized;30 31static DEFINE_MUTEX(vmci_vsock_mutex); /* protects vmci_vsock_transport_cb */32static vmci_vsock_cb vmci_vsock_transport_cb;33static bool vmci_vsock_cb_host_called;34 35/*36 * vmci_get_context_id() - Gets the current context ID.37 *38 * Returns the current context ID.  Note that since this is accessed only39 * from code running in the host, this always returns the host context ID.40 */41u32 vmci_get_context_id(void)42{43	if (vmci_guest_code_active())44		return vmci_get_vm_context_id();45	else if (vmci_host_code_active())46		return VMCI_HOST_CONTEXT_ID;47 48	return VMCI_INVALID_ID;49}50EXPORT_SYMBOL_GPL(vmci_get_context_id);51 52/*53 * vmci_register_vsock_callback() - Register the VSOCK vmci_transport callback.54 *55 * The callback will be called when the first host or guest becomes active,56 * or if they are already active when this function is called.57 * To unregister the callback, call this function with NULL parameter.58 *59 * Returns 0 on success. -EBUSY if a callback is already registered.60 */61int vmci_register_vsock_callback(vmci_vsock_cb callback)62{63	int err = 0;64 65	mutex_lock(&vmci_vsock_mutex);66 67	if (vmci_vsock_transport_cb && callback) {68		err = -EBUSY;69		goto out;70	}71 72	vmci_vsock_transport_cb = callback;73 74	if (!vmci_vsock_transport_cb) {75		vmci_vsock_cb_host_called = false;76		goto out;77	}78 79	if (vmci_guest_code_active())80		vmci_vsock_transport_cb(false);81 82	if (vmci_host_users() > 0) {83		vmci_vsock_cb_host_called = true;84		vmci_vsock_transport_cb(true);85	}86 87out:88	mutex_unlock(&vmci_vsock_mutex);89	return err;90}91EXPORT_SYMBOL_GPL(vmci_register_vsock_callback);92 93void vmci_call_vsock_callback(bool is_host)94{95	mutex_lock(&vmci_vsock_mutex);96 97	if (!vmci_vsock_transport_cb)98		goto out;99 100	/* In the host, this function could be called multiple times,101	 * but we want to register it only once.102	 */103	if (is_host) {104		if (vmci_vsock_cb_host_called)105			goto out;106 107		vmci_vsock_cb_host_called = true;108	}109 110	vmci_vsock_transport_cb(is_host);111out:112	mutex_unlock(&vmci_vsock_mutex);113}114 115static int __init vmci_drv_init(void)116{117	int vmci_err;118	int error;119 120	vmci_err = vmci_event_init();121	if (vmci_err < VMCI_SUCCESS) {122		pr_err("Failed to initialize VMCIEvent (result=%d)\n",123		       vmci_err);124		return -EINVAL;125	}126 127	if (!vmci_disable_guest) {128		error = vmci_guest_init();129		if (error) {130			pr_warn("Failed to initialize guest personality (err=%d)\n",131				error);132		} else {133			vmci_guest_personality_initialized = true;134			pr_info("Guest personality initialized and is %s\n",135				vmci_guest_code_active() ?136				"active" : "inactive");137		}138	}139 140	if (!vmci_disable_host) {141		error = vmci_host_init();142		if (error) {143			pr_warn("Unable to initialize host personality (err=%d)\n",144				error);145		} else {146			vmci_host_personality_initialized = true;147			pr_info("Initialized host personality\n");148		}149	}150 151	if (!vmci_guest_personality_initialized &&152	    !vmci_host_personality_initialized) {153		vmci_event_exit();154		return -ENODEV;155	}156 157	return 0;158}159module_init(vmci_drv_init);160 161static void __exit vmci_drv_exit(void)162{163	if (vmci_guest_personality_initialized)164		vmci_guest_exit();165 166	if (vmci_host_personality_initialized)167		vmci_host_exit();168 169	vmci_event_exit();170}171module_exit(vmci_drv_exit);172 173MODULE_AUTHOR("VMware, Inc.");174MODULE_DESCRIPTION("VMware Virtual Machine Communication Interface.");175MODULE_VERSION("1.1.6.0-k");176MODULE_LICENSE("GPL v2");177