• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* visorbus.h
2  *
3  * Copyright (C) 2010 - 2013 UNISYS CORPORATION
4  * All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or (at
9  * your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
14  * NON INFRINGEMENT.  See the GNU General Public License for more
15  * details.
16  */
17 
18 /*
19  *  This header file is to be included by other kernel mode components that
20  *  implement a particular kind of visor_device.  Each of these other kernel
21  *  mode components is called a visor device driver.  Refer to visortemplate
22  *  for a minimal sample visor device driver.
23  *
24  *  There should be nothing in this file that is private to the visorbus
25  *  bus implementation itself.
26  *
27  */
28 
29 #ifndef __VISORBUS_H__
30 #define __VISORBUS_H__
31 
32 #include <linux/device.h>
33 #include <linux/module.h>
34 #include <linux/poll.h>
35 #include <linux/kernel.h>
36 #include <linux/uuid.h>
37 #include <linux/seq_file.h>
38 #include <linux/slab.h>
39 
40 #include "channel.h"
41 
42 struct visor_driver;
43 struct visor_device;
44 extern struct bus_type visorbus_type;
45 
46 typedef void (*visorbus_state_complete_func) (struct visor_device *dev,
47 					      int status);
48 struct visorchipset_state {
49 	u32 created:1;
50 	u32 attached:1;
51 	u32 configured:1;
52 	u32 running:1;
53 	/* Add new fields above. */
54 	/* Remaining bits in this 32-bit word are unused. */
55 };
56 
57 /** This struct describes a specific Supervisor channel, by providing its
58  *  GUID, name, and sizes.
59  */
60 struct visor_channeltype_descriptor {
61 	const uuid_le guid;
62 	const char *name;
63 };
64 
65 /**
66  * struct visor_driver - Information provided by each visor driver when it
67  * registers with the visorbus driver.
68  * @name:		Name of the visor driver.
69  * @owner:		The module owner.
70  * @channel_types:	Types of channels handled by this driver, ending with
71  *			a zero GUID. Our specialized BUS.match() method knows
72  *			about this list, and uses it to determine whether this
73  *			driver will in fact handle a new device that it has
74  *			detected.
75  * @probe:		Called when a new device comes online, by our probe()
76  *			function specified by driver.probe() (triggered
77  *			ultimately by some call to driver_register(),
78  *			bus_add_driver(), or driver_attach()).
79  * @remove:		Called when a new device is removed, by our remove()
80  *			function specified by driver.remove() (triggered
81  *			ultimately by some call to device_release_driver()).
82  * @channel_interrupt:	Called periodically, whenever there is a possiblity
83  *			that "something interesting" may have happened to the
84  *			channel.
85  * @pause:		Called to initiate a change of the device's state.  If
86  *			the return valu`e is < 0, there was an error and the
87  *			state transition will NOT occur.  If the return value
88  *			is >= 0, then the state transition was INITIATED
89  *			successfully, and complete_func() will be called (or
90  *			was just called) with the final status when either the
91  *			state transition fails or completes successfully.
92  * @resume:		Behaves similar to pause.
93  * @driver:		Private reference to the device driver. For use by bus
94  *			driver only.
95  */
96 struct visor_driver {
97 	const char *name;
98 	struct module *owner;
99 	struct visor_channeltype_descriptor *channel_types;
100 	int (*probe)(struct visor_device *dev);
101 	void (*remove)(struct visor_device *dev);
102 	void (*channel_interrupt)(struct visor_device *dev);
103 	int (*pause)(struct visor_device *dev,
104 		     visorbus_state_complete_func complete_func);
105 	int (*resume)(struct visor_device *dev,
106 		      visorbus_state_complete_func complete_func);
107 
108 	/* These fields are for private use by the bus driver only. */
109 	struct device_driver driver;
110 };
111 
112 #define to_visor_driver(x) ((x) ? \
113 	(container_of(x, struct visor_driver, driver)) : (NULL))
114 
115 /**
116  * struct visor_device - A device type for things "plugged" into the visorbus
117  * bus
118  * @visorchannel:		Points to the channel that the device is
119  *				associated with.
120  * @channel_type_guid:		Identifies the channel type to the bus driver.
121  * @device:			Device struct meant for use by the bus driver
122  *				only.
123  * @list_all:			Used by the bus driver to enumerate devices.
124  * @timer:		        Timer fired periodically to do interrupt-type
125  *				activity.
126  * @being_removed:		Indicates that the device is being removed from
127  *				the bus. Private bus driver use only.
128  * @visordriver_callback_lock:	Used by the bus driver to lock when handling
129  *				channel events.
130  * @pausing:			Indicates that a change towards a paused state.
131  *				is in progress. Only modified by the bus driver.
132  * @resuming:			Indicates that a change towards a running state
133  *				is in progress. Only modified by the bus driver.
134  * @chipset_bus_no:		Private field used by the bus driver.
135  * @chipset_dev_no:		Private field used the bus driver.
136  * @state:			Used to indicate the current state of the
137  *				device.
138  * @inst:			Unique GUID for this instance of the device.
139  * @name:			Name of the device.
140  * @pending_msg_hdr:		For private use by bus driver to respond to
141  *				hypervisor requests.
142  * @vbus_hdr_info:		A pointer to header info. Private use by bus
143  *				driver.
144  * @partition_uuid:		Indicates client partion id. This should be the
145  *				same across all visor_devices in the current
146  *				guest. Private use by bus driver only.
147  */
148 
149 struct visor_device {
150 	struct visorchannel *visorchannel;
151 	uuid_le channel_type_guid;
152 	/* These fields are for private use by the bus driver only. */
153 	struct device device;
154 	struct list_head list_all;
155 	struct timer_list timer;
156 	bool timer_active;
157 	bool being_removed;
158 	struct mutex visordriver_callback_lock;
159 	bool pausing;
160 	bool resuming;
161 	u32 chipset_bus_no;
162 	u32 chipset_dev_no;
163 	struct visorchipset_state state;
164 	uuid_le inst;
165 	u8 *name;
166 	struct controlvm_message_header *pending_msg_hdr;
167 	void *vbus_hdr_info;
168 	uuid_le partition_uuid;
169 };
170 
171 #define to_visor_device(x) container_of(x, struct visor_device, device)
172 
173 int visorbus_register_visor_driver(struct visor_driver *);
174 void visorbus_unregister_visor_driver(struct visor_driver *);
175 int visorbus_read_channel(struct visor_device *dev,
176 			  unsigned long offset, void *dest,
177 			  unsigned long nbytes);
178 int visorbus_write_channel(struct visor_device *dev,
179 			   unsigned long offset, void *src,
180 			   unsigned long nbytes);
181 void visorbus_enable_channel_interrupts(struct visor_device *dev);
182 void visorbus_disable_channel_interrupts(struct visor_device *dev);
183 
184 /* Levels of severity for diagnostic events, in order from lowest severity to
185  * highest (i.e. fatal errors are the most severe, and should always be logged,
186  * but info events rarely need to be logged except during debugging). The
187  * values DIAG_SEVERITY_ENUM_BEGIN and DIAG_SEVERITY_ENUM_END are not valid
188  * severity values.  They exist merely to dilineate the list, so that future
189  * additions won't require changes to the driver (i.e. when checking for
190  * out-of-range severities in SetSeverity). The values DIAG_SEVERITY_OVERRIDE
191  * and DIAG_SEVERITY_SHUTOFF are not valid severity values for logging events
192  * but they are valid for controlling the amount of event data. Changes made
193  * to the enum, need to be reflected in s-Par.
194  */
195 enum diag_severity {
196 	DIAG_SEVERITY_VERBOSE = 0,
197 	DIAG_SEVERITY_INFO = 1,
198 	DIAG_SEVERITY_WARNING = 2,
199 	DIAG_SEVERITY_ERR = 3,
200 	DIAG_SEVERITY_PRINT = 4,
201 };
202 
203 int visorchannel_signalremove(struct visorchannel *channel, u32 queue,
204 			      void *msg);
205 int visorchannel_signalinsert(struct visorchannel *channel, u32 queue,
206 			      void *msg);
207 bool visorchannel_signalempty(struct visorchannel *channel, u32 queue);
208 uuid_le visorchannel_get_uuid(struct visorchannel *channel);
209 
210 #define BUS_ROOT_DEVICE		UINT_MAX
211 struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
212 					       struct visor_device *from);
213 #endif
214