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 
38 #include "periodic_work.h"
39 #include "channel.h"
40 
41 struct visor_driver;
42 struct visor_device;
43 extern struct bus_type visorbus_type;
44 
45 typedef void (*visorbus_state_complete_func) (struct visor_device *dev,
46 					      int status);
47 struct visorchipset_state {
48 	u32 created:1;
49 	u32 attached:1;
50 	u32 configured:1;
51 	u32 running:1;
52 	/* Add new fields above. */
53 	/* Remaining bits in this 32-bit word are unused. */
54 };
55 
56 /** This struct describes a specific Supervisor channel, by providing its
57  *  GUID, name, and sizes.
58  */
59 struct visor_channeltype_descriptor {
60 	const uuid_le guid;
61 	const char *name;
62 };
63 
64 /** Information provided by each visor driver when it registers with the
65  *  visorbus driver.
66  */
67 struct visor_driver {
68 	const char *name;
69 	const char *version;
70 	const char *vertag;
71 	const char *build_date;
72 	const char *build_time;
73 	struct module *owner;
74 
75 	/** Types of channels handled by this driver, ending with 0 GUID.
76 	 *  Our specialized BUS.match() method knows about this list, and
77 	 *  uses it to determine whether this driver will in fact handle a
78 	 *  new device that it has detected.
79 	 */
80 	struct visor_channeltype_descriptor *channel_types;
81 
82 	/** Called when a new device comes online, by our probe() function
83 	 *  specified by driver.probe() (triggered ultimately by some call
84 	 *  to driver_register() / bus_add_driver() / driver_attach()).
85 	 */
86 	int (*probe)(struct visor_device *dev);
87 
88 	/** Called when a new device is removed, by our remove() function
89 	 *  specified by driver.remove() (triggered ultimately by some call
90 	 *  to device_release_driver()).
91 	 */
92 	void (*remove)(struct visor_device *dev);
93 
94 	/** Called periodically, whenever there is a possibility that
95 	 *  "something interesting" may have happened to the channel state.
96 	 */
97 	void (*channel_interrupt)(struct visor_device *dev);
98 
99 	/** Called to initiate a change of the device's state.  If the return
100 	 *  valu`e is < 0, there was an error and the state transition will NOT
101 	 *  occur.  If the return value is >= 0, then the state transition was
102 	 *  INITIATED successfully, and complete_func() will be called (or was
103 	 *  just called) with the final status when either the state transition
104 	 *  fails or completes successfully.
105 	 */
106 	int (*pause)(struct visor_device *dev,
107 		     visorbus_state_complete_func complete_func);
108 	int (*resume)(struct visor_device *dev,
109 		      visorbus_state_complete_func complete_func);
110 
111 	/** These fields are for private use by the bus driver only. */
112 	struct device_driver driver;
113 	struct driver_attribute version_attr;
114 };
115 
116 #define to_visor_driver(x) ((x) ? \
117 	(container_of(x, struct visor_driver, driver)) : (NULL))
118 
119 /** A device type for things "plugged" into the visorbus bus */
120 
121 struct visor_device {
122 	/** visor driver can use the visorchannel member with the functions
123 	 *  defined in visorchannel.h to access the channel
124 	 */
125 	struct visorchannel *visorchannel;
126 	uuid_le channel_type_guid;
127 	u64 channel_bytes;
128 
129 	/** These fields are for private use by the bus driver only.
130 	 *  A notable exception is that the visor driver can use
131 	 *  visor_get_drvdata() and visor_set_drvdata() to retrieve or stash
132 	 *  private visor driver specific data within the device member.
133 	 */
134 	struct device device;
135 	struct list_head list_all;
136 	struct periodic_work *periodic_work;
137 	bool being_removed;
138 	bool responded_to_device_create;
139 	struct kobject kobjdevmajorminor; /* visorbus<x>/dev<y>/devmajorminor/*/
140 	struct {
141 		int major, minor;
142 		void *attr;	/* private use by devmajorminor_attr.c you can
143 				   * change this constant to whatever you
144 				   * want; */
145 	} devnodes[5];
146 	/* the code will detect and behave appropriately) */
147 	struct semaphore visordriver_callback_lock;
148 	bool pausing;
149 	bool resuming;
150 	u32 chipset_bus_no;
151 	u32 chipset_dev_no;
152 	struct visorchipset_state state;
153 	uuid_le type;
154 	uuid_le inst;
155 	u8 *name;
156 	u8 *description;
157 	struct controlvm_message_header *pending_msg_hdr;
158 	void *vbus_hdr_info;
159 	u32 switch_no;
160 	u32 internal_port_no;
161 	uuid_le partition_uuid;
162 };
163 
164 #define to_visor_device(x) container_of(x, struct visor_device, device)
165 
166 #ifndef STANDALONE_CLIENT
167 int visorbus_register_visor_driver(struct visor_driver *);
168 void visorbus_unregister_visor_driver(struct visor_driver *);
169 int visorbus_read_channel(struct visor_device *dev,
170 			  unsigned long offset, void *dest,
171 			  unsigned long nbytes);
172 int visorbus_write_channel(struct visor_device *dev,
173 			   unsigned long offset, void *src,
174 			   unsigned long nbytes);
175 int visorbus_clear_channel(struct visor_device *dev,
176 			   unsigned long offset, u8 ch, unsigned long nbytes);
177 int visorbus_registerdevnode(struct visor_device *dev,
178 			     const char *name, int major, int minor);
179 void visorbus_enable_channel_interrupts(struct visor_device *dev);
180 void visorbus_disable_channel_interrupts(struct visor_device *dev);
181 #endif
182 
183 /* Note that for visorchannel_create()
184  * <channel_bytes> and <guid> arguments may be 0 if we are a channel CLIENT.
185  * In this case, the values can simply be read from the channel header.
186  */
187 struct visorchannel *visorchannel_create(u64 physaddr,
188 					 unsigned long channel_bytes,
189 					 gfp_t gfp, uuid_le guid);
190 struct visorchannel *visorchannel_create_with_lock(u64 physaddr,
191 						   unsigned long channel_bytes,
192 						   gfp_t gfp, uuid_le guid);
193 void visorchannel_destroy(struct visorchannel *channel);
194 int visorchannel_read(struct visorchannel *channel, ulong offset,
195 		      void *local, ulong nbytes);
196 int visorchannel_write(struct visorchannel *channel, ulong offset,
197 		       void *local, ulong nbytes);
198 int visorchannel_clear(struct visorchannel *channel, ulong offset,
199 		       u8 ch, ulong nbytes);
200 bool visorchannel_signalremove(struct visorchannel *channel, u32 queue,
201 			       void *msg);
202 bool visorchannel_signalinsert(struct visorchannel *channel, u32 queue,
203 			       void *msg);
204 bool visorchannel_signalempty(struct visorchannel *channel, u32 queue);
205 
206 int visorchannel_signalqueue_slots_avail(struct visorchannel *channel,
207 					 u32 queue);
208 int visorchannel_signalqueue_max_slots(struct visorchannel *channel, u32 queue);
209 u64 visorchannel_get_physaddr(struct visorchannel *channel);
210 ulong visorchannel_get_nbytes(struct visorchannel *channel);
211 char *visorchannel_id(struct visorchannel *channel, char *s);
212 char *visorchannel_zoneid(struct visorchannel *channel, char *s);
213 u64 visorchannel_get_clientpartition(struct visorchannel *channel);
214 int visorchannel_set_clientpartition(struct visorchannel *channel,
215 				     u64 partition_handle);
216 uuid_le visorchannel_get_uuid(struct visorchannel *channel);
217 char *visorchannel_uuid_id(uuid_le *guid, char *s);
218 void visorchannel_debug(struct visorchannel *channel, int num_queues,
219 			struct seq_file *seq, u32 off);
220 void __iomem *visorchannel_get_header(struct visorchannel *channel);
221 
222 #define BUS_ROOT_DEVICE		UINT_MAX
223 struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
224 					       struct visor_device *from);
225 #endif
226