1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2010 - 2013 UNISYS CORPORATION 4 * All rights reserved. 5 */ 6 7 /* 8 * This header file is to be included by other kernel mode components that 9 * implement a particular kind of visor_device. Each of these other kernel 10 * mode components is called a visor device driver. Refer to visortemplate 11 * for a minimal sample visor device driver. 12 * 13 * There should be nothing in this file that is private to the visorbus 14 * bus implementation itself. 15 */ 16 17 #ifndef __VISORBUS_H__ 18 #define __VISORBUS_H__ 19 20 #include <linux/device.h> 21 22 #define VISOR_CHANNEL_SIGNATURE ('L' << 24 | 'N' << 16 | 'C' << 8 | 'E') 23 24 /* 25 * enum channel_serverstate 26 * @CHANNELSRV_UNINITIALIZED: Channel is in an undefined state. 27 * @CHANNELSRV_READY: Channel has been initialized by server. 28 */ 29 enum channel_serverstate { 30 CHANNELSRV_UNINITIALIZED = 0, 31 CHANNELSRV_READY = 1 32 }; 33 34 /* 35 * enum channel_clientstate 36 * @CHANNELCLI_DETACHED: 37 * @CHANNELCLI_DISABLED: Client can see channel but is NOT allowed to use it 38 * unless given TBD* explicit request 39 * (should actually be < DETACHED). 40 * @CHANNELCLI_ATTACHING: Legacy EFI client request for EFI server to attach. 41 * @CHANNELCLI_ATTACHED: Idle, but client may want to use channel any time. 42 * @CHANNELCLI_BUSY: Client either wants to use or is using channel. 43 * @CHANNELCLI_OWNED: "No worries" state - client can access channel 44 * anytime. 45 */ 46 enum channel_clientstate { 47 CHANNELCLI_DETACHED = 0, 48 CHANNELCLI_DISABLED = 1, 49 CHANNELCLI_ATTACHING = 2, 50 CHANNELCLI_ATTACHED = 3, 51 CHANNELCLI_BUSY = 4, 52 CHANNELCLI_OWNED = 5 53 }; 54 55 /* 56 * Values for VISOR_CHANNEL_PROTOCOL.Features: This define exists so that 57 * a guest can look at the FeatureFlags in the io channel, and configure the 58 * driver to use interrupts or not based on this setting. All feature bits for 59 * all channels should be defined here. The io channel feature bits are defined 60 * below. 61 */ 62 #define VISOR_DRIVER_ENABLES_INTS (0x1ULL << 1) 63 #define VISOR_CHANNEL_IS_POLLING (0x1ULL << 3) 64 #define VISOR_IOVM_OK_DRIVER_DISABLING_INTS (0x1ULL << 4) 65 #define VISOR_DRIVER_DISABLES_INTS (0x1ULL << 5) 66 #define VISOR_DRIVER_ENHANCED_RCVBUF_CHECKING (0x1ULL << 6) 67 68 /* 69 * struct channel_header - Common Channel Header 70 * @signature: Signature. 71 * @legacy_state: DEPRECATED - being replaced by. 72 * @header_size: sizeof(struct channel_header). 73 * @size: Total size of this channel in bytes. 74 * @features: Flags to modify behavior. 75 * @chtype: Channel type: data, bus, control, etc.. 76 * @partition_handle: ID of guest partition. 77 * @handle: Device number of this channel in client. 78 * @ch_space_offset: Offset in bytes to channel specific area. 79 * @version_id: Struct channel_header Version ID. 80 * @partition_index: Index of guest partition. 81 * @zone_uuid: Guid of Channel's zone. 82 * @cli_str_offset: Offset from channel header to null-terminated 83 * ClientString (0 if ClientString not present). 84 * @cli_state_boot: CHANNEL_CLIENTSTATE of pre-boot EFI client of this 85 * channel. 86 * @cmd_state_cli: CHANNEL_COMMANDSTATE (overloaded in Windows drivers, see 87 * ServerStateUp, ServerStateDown, etc). 88 * @cli_state_os: CHANNEL_CLIENTSTATE of Guest OS client of this channel. 89 * @ch_characteristic: CHANNEL_CHARACTERISTIC_<xxx>. 90 * @cmd_state_srv: CHANNEL_COMMANDSTATE (overloaded in Windows drivers, see 91 * ServerStateUp, ServerStateDown, etc). 92 * @srv_state: CHANNEL_SERVERSTATE. 93 * @cli_error_boot: Bits to indicate err states for boot clients, so err 94 * messages can be throttled. 95 * @cli_error_os: Bits to indicate err states for OS clients, so err 96 * messages can be throttled. 97 * @filler: Pad out to 128 byte cacheline. 98 * @recover_channel: Please add all new single-byte values below here. 99 */ 100 struct channel_header { 101 u64 signature; 102 u32 legacy_state; 103 /* SrvState, CliStateBoot, and CliStateOS below */ 104 u32 header_size; 105 u64 size; 106 u64 features; 107 guid_t chtype; 108 u64 partition_handle; 109 u64 handle; 110 u64 ch_space_offset; 111 u32 version_id; 112 u32 partition_index; 113 guid_t zone_guid; 114 u32 cli_str_offset; 115 u32 cli_state_boot; 116 u32 cmd_state_cli; 117 u32 cli_state_os; 118 u32 ch_characteristic; 119 u32 cmd_state_srv; 120 u32 srv_state; 121 u8 cli_error_boot; 122 u8 cli_error_os; 123 u8 filler[1]; 124 u8 recover_channel; 125 } __packed; 126 127 #define VISOR_CHANNEL_ENABLE_INTS (0x1ULL << 0) 128 129 /* 130 * struct signal_queue_header - Subheader for the Signal Type variation of the 131 * Common Channel. 132 * @version: SIGNAL_QUEUE_HEADER Version ID. 133 * @chtype: Queue type: storage, network. 134 * @size: Total size of this queue in bytes. 135 * @sig_base_offset: Offset to signal queue area. 136 * @features: Flags to modify behavior. 137 * @num_sent: Total # of signals placed in this queue. 138 * @num_overflows: Total # of inserts failed due to full queue. 139 * @signal_size: Total size of a signal for this queue. 140 * @max_slots: Max # of slots in queue, 1 slot is always empty. 141 * @max_signals: Max # of signals in queue (MaxSignalSlots-1). 142 * @head: Queue head signal #. 143 * @num_received: Total # of signals removed from this queue. 144 * @tail: Queue tail signal. 145 * @reserved1: Reserved field. 146 * @reserved2: Reserved field. 147 * @client_queue: 148 * @num_irq_received: Total # of Interrupts received. This is incremented by the 149 * ISR in the guest windows driver. 150 * @num_empty: Number of times that visor_signal_remove is called and 151 * returned Empty Status. 152 * @errorflags: Error bits set during SignalReinit to denote trouble with 153 * client's fields. 154 * @filler: Pad out to 64 byte cacheline. 155 */ 156 struct signal_queue_header { 157 /* 1st cache line */ 158 u32 version; 159 u32 chtype; 160 u64 size; 161 u64 sig_base_offset; 162 u64 features; 163 u64 num_sent; 164 u64 num_overflows; 165 u32 signal_size; 166 u32 max_slots; 167 u32 max_signals; 168 u32 head; 169 /* 2nd cache line */ 170 u64 num_received; 171 u32 tail; 172 u32 reserved1; 173 u64 reserved2; 174 u64 client_queue; 175 u64 num_irq_received; 176 u64 num_empty; 177 u32 errorflags; 178 u8 filler[12]; 179 } __packed; 180 181 /* VISORCHANNEL Guids */ 182 /* {414815ed-c58c-11da-95a9-00e08161165f} */ 183 #define VISOR_VHBA_CHANNEL_GUID \ 184 GUID_INIT(0x414815ed, 0xc58c, 0x11da, \ 185 0x95, 0xa9, 0x0, 0xe0, 0x81, 0x61, 0x16, 0x5f) 186 #define VISOR_VHBA_CHANNEL_GUID_STR \ 187 "414815ed-c58c-11da-95a9-00e08161165f" 188 struct visorchipset_state { 189 u32 created:1; 190 u32 attached:1; 191 u32 configured:1; 192 u32 running:1; 193 /* Remaining bits in this 32-bit word are reserved. */ 194 }; 195 196 /** 197 * struct visor_device - A device type for things "plugged" into the visorbus 198 * bus 199 * @visorchannel: Points to the channel that the device is 200 * associated with. 201 * @channel_type_guid: Identifies the channel type to the bus driver. 202 * @device: Device struct meant for use by the bus driver 203 * only. 204 * @list_all: Used by the bus driver to enumerate devices. 205 * @timer: Timer fired periodically to do interrupt-type 206 * activity. 207 * @being_removed: Indicates that the device is being removed from 208 * the bus. Private bus driver use only. 209 * @visordriver_callback_lock: Used by the bus driver to lock when adding and 210 * removing devices. 211 * @pausing: Indicates that a change towards a paused state. 212 * is in progress. Only modified by the bus driver. 213 * @resuming: Indicates that a change towards a running state 214 * is in progress. Only modified by the bus driver. 215 * @chipset_bus_no: Private field used by the bus driver. 216 * @chipset_dev_no: Private field used the bus driver. 217 * @state: Used to indicate the current state of the 218 * device. 219 * @inst: Unique GUID for this instance of the device. 220 * @name: Name of the device. 221 * @pending_msg_hdr: For private use by bus driver to respond to 222 * hypervisor requests. 223 * @vbus_hdr_info: A pointer to header info. Private use by bus 224 * driver. 225 * @partition_guid: Indicates client partion id. This should be the 226 * same across all visor_devices in the current 227 * guest. Private use by bus driver only. 228 */ 229 struct visor_device { 230 struct visorchannel *visorchannel; 231 guid_t channel_type_guid; 232 /* These fields are for private use by the bus driver only. */ 233 struct device device; 234 struct list_head list_all; 235 struct timer_list timer; 236 bool timer_active; 237 bool being_removed; 238 struct mutex visordriver_callback_lock; /* synchronize probe/remove */ 239 bool pausing; 240 bool resuming; 241 u32 chipset_bus_no; 242 u32 chipset_dev_no; 243 struct visorchipset_state state; 244 guid_t inst; 245 u8 *name; 246 struct controlvm_message_header *pending_msg_hdr; 247 void *vbus_hdr_info; 248 guid_t partition_guid; 249 struct dentry *debugfs_dir; 250 struct dentry *debugfs_bus_info; 251 }; 252 253 #define to_visor_device(x) container_of(x, struct visor_device, device) 254 255 typedef void (*visorbus_state_complete_func) (struct visor_device *dev, 256 int status); 257 258 /* 259 * This struct describes a specific visor channel, by providing its GUID, name, 260 * and sizes. 261 */ 262 struct visor_channeltype_descriptor { 263 const guid_t guid; 264 const char *name; 265 u64 min_bytes; 266 u32 version; 267 }; 268 269 /** 270 * struct visor_driver - Information provided by each visor driver when it 271 * registers with the visorbus driver 272 * @name: Name of the visor driver. 273 * @owner: The module owner. 274 * @channel_types: Types of channels handled by this driver, ending with 275 * a zero GUID. Our specialized BUS.match() method knows 276 * about this list, and uses it to determine whether this 277 * driver will in fact handle a new device that it has 278 * detected. 279 * @probe: Called when a new device comes online, by our probe() 280 * function specified by driver.probe() (triggered 281 * ultimately by some call to driver_register(), 282 * bus_add_driver(), or driver_attach()). 283 * @remove: Called when a new device is removed, by our remove() 284 * function specified by driver.remove() (triggered 285 * ultimately by some call to device_release_driver()). 286 * @channel_interrupt: Called periodically, whenever there is a possiblity 287 * that "something interesting" may have happened to the 288 * channel. 289 * @pause: Called to initiate a change of the device's state. If 290 * the return valu`e is < 0, there was an error and the 291 * state transition will NOT occur. If the return value 292 * is >= 0, then the state transition was INITIATED 293 * successfully, and complete_func() will be called (or 294 * was just called) with the final status when either the 295 * state transition fails or completes successfully. 296 * @resume: Behaves similar to pause. 297 * @driver: Private reference to the device driver. For use by bus 298 * driver only. 299 */ 300 struct visor_driver { 301 const char *name; 302 struct module *owner; 303 struct visor_channeltype_descriptor *channel_types; 304 int (*probe)(struct visor_device *dev); 305 void (*remove)(struct visor_device *dev); 306 void (*channel_interrupt)(struct visor_device *dev); 307 int (*pause)(struct visor_device *dev, 308 visorbus_state_complete_func complete_func); 309 int (*resume)(struct visor_device *dev, 310 visorbus_state_complete_func complete_func); 311 312 /* These fields are for private use by the bus driver only. */ 313 struct device_driver driver; 314 }; 315 316 #define to_visor_driver(x) (container_of(x, struct visor_driver, driver)) 317 318 int visor_check_channel(struct channel_header *ch, struct device *dev, 319 const guid_t *expected_uuid, char *chname, 320 u64 expected_min_bytes, u32 expected_version, 321 u64 expected_signature); 322 323 int visorbus_register_visor_driver(struct visor_driver *drv); 324 void visorbus_unregister_visor_driver(struct visor_driver *drv); 325 int visorbus_read_channel(struct visor_device *dev, 326 unsigned long offset, void *dest, 327 unsigned long nbytes); 328 int visorbus_write_channel(struct visor_device *dev, 329 unsigned long offset, void *src, 330 unsigned long nbytes); 331 int visorbus_enable_channel_interrupts(struct visor_device *dev); 332 void visorbus_disable_channel_interrupts(struct visor_device *dev); 333 334 int visorchannel_signalremove(struct visorchannel *channel, u32 queue, 335 void *msg); 336 int visorchannel_signalinsert(struct visorchannel *channel, u32 queue, 337 void *msg); 338 bool visorchannel_signalempty(struct visorchannel *channel, u32 queue); 339 const guid_t *visorchannel_get_guid(struct visorchannel *channel); 340 341 #define BUS_ROOT_DEVICE UINT_MAX 342 struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no, 343 struct visor_device *from); 344 #endif 345