Ke Dong | eb337a3 | 2012-09-26 19:17:39 -0700 | [diff] [blame] | 1 | #ifndef _SCSI_SCSI_HOST_H |
| 2 | #define _SCSI_SCSI_HOST_H |
| 3 | |
| 4 | #include <linux/device.h> |
| 5 | #include <linux/list.h> |
| 6 | #include <linux/types.h> |
| 7 | #include <linux/workqueue.h> |
| 8 | #include <linux/mutex.h> |
| 9 | #include <scsi/scsi.h> |
| 10 | |
| 11 | struct request_queue; |
| 12 | struct block_device; |
| 13 | struct completion; |
| 14 | struct module; |
| 15 | struct scsi_cmnd; |
| 16 | struct scsi_device; |
| 17 | struct scsi_target; |
| 18 | struct Scsi_Host; |
| 19 | struct scsi_host_cmd_pool; |
| 20 | struct scsi_transport_template; |
| 21 | struct blk_queue_tags; |
| 22 | |
| 23 | |
| 24 | /* |
| 25 | * The various choices mean: |
| 26 | * NONE: Self evident. Host adapter is not capable of scatter-gather. |
| 27 | * ALL: Means that the host adapter module can do scatter-gather, |
| 28 | * and that there is no limit to the size of the table to which |
| 29 | * we scatter/gather data. The value we set here is the maximum |
| 30 | * single element sglist. To use chained sglists, the adapter |
| 31 | * has to set a value beyond ALL (and correctly use the chain |
| 32 | * handling API. |
| 33 | * Anything else: Indicates the maximum number of chains that can be |
| 34 | * used in one scatter-gather request. |
| 35 | */ |
| 36 | #define SG_NONE 0 |
| 37 | #define SG_ALL SCSI_MAX_SG_SEGMENTS |
| 38 | |
| 39 | #define MODE_UNKNOWN 0x00 |
| 40 | #define MODE_INITIATOR 0x01 |
| 41 | #define MODE_TARGET 0x02 |
| 42 | |
| 43 | #define DISABLE_CLUSTERING 0 |
| 44 | #define ENABLE_CLUSTERING 1 |
| 45 | |
| 46 | struct scsi_host_template { |
| 47 | struct module *module; |
| 48 | const char *name; |
| 49 | |
| 50 | /* |
Ke Dong | d045664 | 2012-09-26 19:22:56 -0700 | [diff] [blame] | 51 | * support to scattered spinup in various drivers |
| 52 | */ |
| 53 | unsigned char support_scattered_spinup; |
| 54 | |
| 55 | /* |
Ke Dong | eb337a3 | 2012-09-26 19:17:39 -0700 | [diff] [blame] | 56 | * Used to initialize old-style drivers. For new-style drivers |
| 57 | * just perform all work in your module initialization function. |
| 58 | * |
| 59 | * Status: OBSOLETE |
| 60 | */ |
| 61 | int (* detect)(struct scsi_host_template *); |
| 62 | |
| 63 | /* |
| 64 | * Used as unload callback for hosts with old-style drivers. |
| 65 | * |
| 66 | * Status: OBSOLETE |
| 67 | */ |
| 68 | int (* release)(struct Scsi_Host *); |
| 69 | |
| 70 | /* |
| 71 | * The info function will return whatever useful information the |
| 72 | * developer sees fit. If not provided, then the name field will |
| 73 | * be used instead. |
| 74 | * |
| 75 | * Status: OPTIONAL |
| 76 | */ |
| 77 | const char *(* info)(struct Scsi_Host *); |
| 78 | |
| 79 | /* |
| 80 | * Ioctl interface |
| 81 | * |
| 82 | * Status: OPTIONAL |
| 83 | */ |
| 84 | int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg); |
| 85 | |
| 86 | |
| 87 | #ifdef CONFIG_COMPAT |
| 88 | /* |
| 89 | * Compat handler. Handle 32bit ABI. |
| 90 | * When unknown ioctl is passed return -ENOIOCTLCMD. |
| 91 | * |
| 92 | * Status: OPTIONAL |
| 93 | */ |
| 94 | int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg); |
| 95 | #endif |
| 96 | |
| 97 | /* |
| 98 | * The queuecommand function is used to queue up a scsi |
| 99 | * command block to the LLDD. When the driver finished |
| 100 | * processing the command the done callback is invoked. |
| 101 | * |
| 102 | * If queuecommand returns 0, then the HBA has accepted the |
| 103 | * command. The done() function must be called on the command |
| 104 | * when the driver has finished with it. (you may call done on the |
| 105 | * command before queuecommand returns, but in this case you |
| 106 | * *must* return 0 from queuecommand). |
| 107 | * |
| 108 | * Queuecommand may also reject the command, in which case it may |
| 109 | * not touch the command and must not call done() for it. |
| 110 | * |
| 111 | * There are two possible rejection returns: |
| 112 | * |
| 113 | * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but |
| 114 | * allow commands to other devices serviced by this host. |
| 115 | * |
| 116 | * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this |
| 117 | * host temporarily. |
| 118 | * |
| 119 | * For compatibility, any other non-zero return is treated the |
| 120 | * same as SCSI_MLQUEUE_HOST_BUSY. |
| 121 | * |
| 122 | * NOTE: "temporarily" means either until the next command for# |
| 123 | * this device/host completes, or a period of time determined by |
| 124 | * I/O pressure in the system if there are no other outstanding |
| 125 | * commands. |
| 126 | * |
| 127 | * STATUS: REQUIRED |
| 128 | */ |
| 129 | int (* queuecommand)(struct scsi_cmnd *, |
| 130 | void (*done)(struct scsi_cmnd *)); |
| 131 | |
| 132 | /* |
| 133 | * The transfer functions are used to queue a scsi command to |
| 134 | * the LLD. When the driver is finished processing the command |
| 135 | * the done callback is invoked. |
| 136 | * |
| 137 | * This is called to inform the LLD to transfer |
| 138 | * scsi_bufflen(cmd) bytes. scsi_sg_count(cmd) speciefies the |
| 139 | * number of scatterlist entried in the command and |
| 140 | * scsi_sglist(cmd) returns the scatterlist. |
| 141 | * |
| 142 | * return values: see queuecommand |
| 143 | * |
| 144 | * If the LLD accepts the cmd, it should set the result to an |
| 145 | * appropriate value when completed before calling the done function. |
| 146 | * |
| 147 | * STATUS: REQUIRED FOR TARGET DRIVERS |
| 148 | */ |
| 149 | /* TODO: rename */ |
| 150 | int (* transfer_response)(struct scsi_cmnd *, |
| 151 | void (*done)(struct scsi_cmnd *)); |
| 152 | |
| 153 | /* |
| 154 | * This is an error handling strategy routine. You don't need to |
| 155 | * define one of these if you don't want to - there is a default |
| 156 | * routine that is present that should work in most cases. For those |
| 157 | * driver authors that have the inclination and ability to write their |
| 158 | * own strategy routine, this is where it is specified. Note - the |
| 159 | * strategy routine is *ALWAYS* run in the context of the kernel eh |
| 160 | * thread. Thus you are guaranteed to *NOT* be in an interrupt |
| 161 | * handler when you execute this, and you are also guaranteed to |
| 162 | * *NOT* have any other commands being queued while you are in the |
| 163 | * strategy routine. When you return from this function, operations |
| 164 | * return to normal. |
| 165 | * |
| 166 | * See scsi_error.c scsi_unjam_host for additional comments about |
| 167 | * what this function should and should not be attempting to do. |
| 168 | * |
| 169 | * Status: REQUIRED (at least one of them) |
| 170 | */ |
| 171 | int (* eh_abort_handler)(struct scsi_cmnd *); |
| 172 | int (* eh_device_reset_handler)(struct scsi_cmnd *); |
| 173 | int (* eh_target_reset_handler)(struct scsi_cmnd *); |
| 174 | int (* eh_bus_reset_handler)(struct scsi_cmnd *); |
| 175 | int (* eh_host_reset_handler)(struct scsi_cmnd *); |
| 176 | |
| 177 | /* |
| 178 | * Before the mid layer attempts to scan for a new device where none |
| 179 | * currently exists, it will call this entry in your driver. Should |
| 180 | * your driver need to allocate any structs or perform any other init |
| 181 | * items in order to send commands to a currently unused target/lun |
| 182 | * combo, then this is where you can perform those allocations. This |
| 183 | * is specifically so that drivers won't have to perform any kind of |
| 184 | * "is this a new device" checks in their queuecommand routine, |
| 185 | * thereby making the hot path a bit quicker. |
| 186 | * |
| 187 | * Return values: 0 on success, non-0 on failure |
| 188 | * |
| 189 | * Deallocation: If we didn't find any devices at this ID, you will |
| 190 | * get an immediate call to slave_destroy(). If we find something |
| 191 | * here then you will get a call to slave_configure(), then the |
| 192 | * device will be used for however long it is kept around, then when |
| 193 | * the device is removed from the system (or * possibly at reboot |
| 194 | * time), you will then get a call to slave_destroy(). This is |
| 195 | * assuming you implement slave_configure and slave_destroy. |
| 196 | * However, if you allocate memory and hang it off the device struct, |
| 197 | * then you must implement the slave_destroy() routine at a minimum |
| 198 | * in order to avoid leaking memory |
| 199 | * each time a device is tore down. |
| 200 | * |
| 201 | * Status: OPTIONAL |
| 202 | */ |
| 203 | int (* slave_alloc)(struct scsi_device *); |
| 204 | |
| 205 | /* |
| 206 | * Once the device has responded to an INQUIRY and we know the |
| 207 | * device is online, we call into the low level driver with the |
| 208 | * struct scsi_device *. If the low level device driver implements |
| 209 | * this function, it *must* perform the task of setting the queue |
| 210 | * depth on the device. All other tasks are optional and depend |
| 211 | * on what the driver supports and various implementation details. |
| 212 | * |
| 213 | * Things currently recommended to be handled at this time include: |
| 214 | * |
| 215 | * 1. Setting the device queue depth. Proper setting of this is |
| 216 | * described in the comments for scsi_adjust_queue_depth. |
| 217 | * 2. Determining if the device supports the various synchronous |
| 218 | * negotiation protocols. The device struct will already have |
| 219 | * responded to INQUIRY and the results of the standard items |
| 220 | * will have been shoved into the various device flag bits, eg. |
| 221 | * device->sdtr will be true if the device supports SDTR messages. |
| 222 | * 3. Allocating command structs that the device will need. |
| 223 | * 4. Setting the default timeout on this device (if needed). |
| 224 | * 5. Anything else the low level driver might want to do on a device |
| 225 | * specific setup basis... |
| 226 | * 6. Return 0 on success, non-0 on error. The device will be marked |
| 227 | * as offline on error so that no access will occur. If you return |
| 228 | * non-0, your slave_destroy routine will never get called for this |
| 229 | * device, so don't leave any loose memory hanging around, clean |
| 230 | * up after yourself before returning non-0 |
| 231 | * |
| 232 | * Status: OPTIONAL |
| 233 | */ |
| 234 | int (* slave_configure)(struct scsi_device *); |
| 235 | |
| 236 | /* |
| 237 | * Immediately prior to deallocating the device and after all activity |
| 238 | * has ceased the mid layer calls this point so that the low level |
| 239 | * driver may completely detach itself from the scsi device and vice |
| 240 | * versa. The low level driver is responsible for freeing any memory |
| 241 | * it allocated in the slave_alloc or slave_configure calls. |
| 242 | * |
| 243 | * Status: OPTIONAL |
| 244 | */ |
| 245 | void (* slave_destroy)(struct scsi_device *); |
| 246 | |
| 247 | /* |
| 248 | * Before the mid layer attempts to scan for a new device attached |
| 249 | * to a target where no target currently exists, it will call this |
| 250 | * entry in your driver. Should your driver need to allocate any |
| 251 | * structs or perform any other init items in order to send commands |
| 252 | * to a currently unused target, then this is where you can perform |
| 253 | * those allocations. |
| 254 | * |
| 255 | * Return values: 0 on success, non-0 on failure |
| 256 | * |
| 257 | * Status: OPTIONAL |
| 258 | */ |
| 259 | int (* target_alloc)(struct scsi_target *); |
| 260 | |
| 261 | /* |
| 262 | * Immediately prior to deallocating the target structure, and |
| 263 | * after all activity to attached scsi devices has ceased, the |
| 264 | * midlayer calls this point so that the driver may deallocate |
| 265 | * and terminate any references to the target. |
| 266 | * |
| 267 | * Status: OPTIONAL |
| 268 | */ |
| 269 | void (* target_destroy)(struct scsi_target *); |
| 270 | |
| 271 | /* |
| 272 | * If a host has the ability to discover targets on its own instead |
| 273 | * of scanning the entire bus, it can fill in this function and |
| 274 | * call scsi_scan_host(). This function will be called periodically |
| 275 | * until it returns 1 with the scsi_host and the elapsed time of |
| 276 | * the scan in jiffies. |
| 277 | * |
| 278 | * Status: OPTIONAL |
| 279 | */ |
| 280 | int (* scan_finished)(struct Scsi_Host *, unsigned long); |
| 281 | |
| 282 | /* |
| 283 | * If the host wants to be called before the scan starts, but |
| 284 | * after the midlayer has set up ready for the scan, it can fill |
| 285 | * in this function. |
| 286 | * |
| 287 | * Status: OPTIONAL |
| 288 | */ |
| 289 | void (* scan_start)(struct Scsi_Host *); |
| 290 | |
| 291 | /* |
| 292 | * Fill in this function to allow the queue depth of this host |
| 293 | * to be changeable (on a per device basis). Returns either |
| 294 | * the current queue depth setting (may be different from what |
| 295 | * was passed in) or an error. An error should only be |
| 296 | * returned if the requested depth is legal but the driver was |
| 297 | * unable to set it. If the requested depth is illegal, the |
| 298 | * driver should set and return the closest legal queue depth. |
| 299 | * |
| 300 | * Status: OPTIONAL |
| 301 | */ |
| 302 | int (* change_queue_depth)(struct scsi_device *, int); |
| 303 | |
| 304 | /* |
| 305 | * Fill in this function to allow the changing of tag types |
| 306 | * (this also allows the enabling/disabling of tag command |
| 307 | * queueing). An error should only be returned if something |
| 308 | * went wrong in the driver while trying to set the tag type. |
| 309 | * If the driver doesn't support the requested tag type, then |
| 310 | * it should set the closest type it does support without |
| 311 | * returning an error. Returns the actual tag type set. |
| 312 | * |
| 313 | * Status: OPTIONAL |
| 314 | */ |
| 315 | int (* change_queue_type)(struct scsi_device *, int); |
| 316 | |
| 317 | /* |
| 318 | * This function determines the BIOS parameters for a given |
| 319 | * harddisk. These tend to be numbers that are made up by |
| 320 | * the host adapter. Parameters: |
| 321 | * size, device, list (heads, sectors, cylinders) |
| 322 | * |
| 323 | * Status: OPTIONAL |
| 324 | */ |
| 325 | int (* bios_param)(struct scsi_device *, struct block_device *, |
| 326 | sector_t, int []); |
| 327 | |
| 328 | /* |
| 329 | * Can be used to export driver statistics and other infos to the |
| 330 | * world outside the kernel ie. userspace and it also provides an |
| 331 | * interface to feed the driver with information. |
| 332 | * |
| 333 | * Status: OBSOLETE |
| 334 | */ |
| 335 | int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int); |
| 336 | |
| 337 | /* |
| 338 | * This is an optional routine that allows the transport to become |
| 339 | * involved when a scsi io timer fires. The return value tells the |
| 340 | * timer routine how to finish the io timeout handling: |
| 341 | * EH_HANDLED: I fixed the error, please complete the command |
| 342 | * EH_RESET_TIMER: I need more time, reset the timer and |
| 343 | * begin counting again |
| 344 | * EH_NOT_HANDLED Begin normal error recovery |
| 345 | * |
| 346 | * Status: OPTIONAL |
| 347 | */ |
| 348 | enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); |
| 349 | |
| 350 | /* |
| 351 | * Name of proc directory |
| 352 | */ |
| 353 | const char *proc_name; |
| 354 | |
| 355 | /* |
| 356 | * Used to store the procfs directory if a driver implements the |
| 357 | * proc_info method. |
| 358 | */ |
| 359 | struct proc_dir_entry *proc_dir; |
| 360 | |
| 361 | /* |
| 362 | * This determines if we will use a non-interrupt driven |
| 363 | * or an interrupt driven scheme. It is set to the maximum number |
| 364 | * of simultaneous commands a given host adapter will accept. |
| 365 | */ |
| 366 | int can_queue; |
| 367 | |
| 368 | /* |
| 369 | * In many instances, especially where disconnect / reconnect are |
| 370 | * supported, our host also has an ID on the SCSI bus. If this is |
| 371 | * the case, then it must be reserved. Please set this_id to -1 if |
| 372 | * your setup is in single initiator mode, and the host lacks an |
| 373 | * ID. |
| 374 | */ |
| 375 | int this_id; |
| 376 | |
| 377 | /* |
| 378 | * This determines the degree to which the host adapter is capable |
| 379 | * of scatter-gather. |
| 380 | */ |
| 381 | unsigned short sg_tablesize; |
| 382 | |
| 383 | /* |
| 384 | * Set this if the host adapter has limitations beside segment count. |
| 385 | */ |
| 386 | unsigned short max_sectors; |
| 387 | |
| 388 | /* |
| 389 | * DMA scatter gather segment boundary limit. A segment crossing this |
| 390 | * boundary will be split in two. |
| 391 | */ |
| 392 | unsigned long dma_boundary; |
| 393 | |
| 394 | /* |
| 395 | * This specifies "machine infinity" for host templates which don't |
| 396 | * limit the transfer size. Note this limit represents an absolute |
| 397 | * maximum, and may be over the transfer limits allowed for |
| 398 | * individual devices (e.g. 256 for SCSI-1). |
| 399 | */ |
| 400 | #define SCSI_DEFAULT_MAX_SECTORS 1024 |
| 401 | |
| 402 | /* |
| 403 | * True if this host adapter can make good use of linked commands. |
| 404 | * This will allow more than one command to be queued to a given |
| 405 | * unit on a given host. Set this to the maximum number of command |
| 406 | * blocks to be provided for each device. Set this to 1 for one |
| 407 | * command block per lun, 2 for two, etc. Do not set this to 0. |
| 408 | * You should make sure that the host adapter will do the right thing |
| 409 | * before you try setting this above 1. |
| 410 | */ |
| 411 | short cmd_per_lun; |
| 412 | |
| 413 | /* |
| 414 | * present contains counter indicating how many boards of this |
| 415 | * type were found when we did the scan. |
| 416 | */ |
| 417 | unsigned char present; |
| 418 | |
| 419 | /* |
| 420 | * This specifies the mode that a LLD supports. |
| 421 | */ |
| 422 | unsigned supported_mode:2; |
| 423 | |
| 424 | /* |
| 425 | * True if this host adapter uses unchecked DMA onto an ISA bus. |
| 426 | */ |
| 427 | unsigned unchecked_isa_dma:1; |
| 428 | |
| 429 | /* |
| 430 | * True if this host adapter can make good use of clustering. |
| 431 | * I originally thought that if the tablesize was large that it |
| 432 | * was a waste of CPU cycles to prepare a cluster list, but |
| 433 | * it works out that the Buslogic is faster if you use a smaller |
| 434 | * number of segments (i.e. use clustering). I guess it is |
| 435 | * inefficient. |
| 436 | */ |
| 437 | unsigned use_clustering:1; |
| 438 | |
| 439 | /* |
| 440 | * True for emulated SCSI host adapters (e.g. ATAPI). |
| 441 | */ |
| 442 | unsigned emulated:1; |
| 443 | |
| 444 | /* |
| 445 | * True if the low-level driver performs its own reset-settle delays. |
| 446 | */ |
| 447 | unsigned skip_settle_delay:1; |
| 448 | |
| 449 | /* |
| 450 | * True if we are using ordered write support. |
| 451 | */ |
| 452 | unsigned ordered_tag:1; |
| 453 | |
| 454 | /* |
| 455 | * Countdown for host blocking with no commands outstanding. |
| 456 | */ |
| 457 | unsigned int max_host_blocked; |
| 458 | |
| 459 | /* |
| 460 | * Default value for the blocking. If the queue is empty, |
| 461 | * host_blocked counts down in the request_fn until it restarts |
| 462 | * host operations as zero is reached. |
| 463 | * |
| 464 | * FIXME: This should probably be a value in the template |
| 465 | */ |
| 466 | #define SCSI_DEFAULT_HOST_BLOCKED 7 |
| 467 | |
| 468 | /* |
| 469 | * Pointer to the sysfs class properties for this host, NULL terminated. |
| 470 | */ |
| 471 | struct device_attribute **shost_attrs; |
| 472 | |
| 473 | /* |
| 474 | * Pointer to the SCSI device properties for this host, NULL terminated. |
| 475 | */ |
| 476 | struct device_attribute **sdev_attrs; |
| 477 | |
| 478 | /* |
| 479 | * List of hosts per template. |
| 480 | * |
| 481 | * This is only for use by scsi_module.c for legacy templates. |
| 482 | * For these access to it is synchronized implicitly by |
| 483 | * module_init/module_exit. |
| 484 | */ |
| 485 | struct list_head legacy_hosts; |
| 486 | |
| 487 | /* |
| 488 | * Vendor Identifier associated with the host |
| 489 | * |
| 490 | * Note: When specifying vendor_id, be sure to read the |
| 491 | * Vendor Type and ID formatting requirements specified in |
| 492 | * scsi_netlink.h |
| 493 | */ |
| 494 | u64 vendor_id; |
| 495 | }; |
| 496 | |
| 497 | /* |
| 498 | * shost state: If you alter this, you also need to alter scsi_sysfs.c |
| 499 | * (for the ascii descriptions) and the state model enforcer: |
| 500 | * scsi_host_set_state() |
| 501 | */ |
| 502 | enum scsi_host_state { |
| 503 | SHOST_CREATED = 1, |
| 504 | SHOST_RUNNING, |
| 505 | SHOST_CANCEL, |
| 506 | SHOST_DEL, |
| 507 | SHOST_RECOVERY, |
| 508 | SHOST_CANCEL_RECOVERY, |
| 509 | SHOST_DEL_RECOVERY, |
| 510 | }; |
| 511 | |
| 512 | struct Scsi_Host { |
| 513 | /* |
| 514 | * __devices is protected by the host_lock, but you should |
| 515 | * usually use scsi_device_lookup / shost_for_each_device |
| 516 | * to access it and don't care about locking yourself. |
| 517 | * In the rare case of beeing in irq context you can use |
| 518 | * their __ prefixed variants with the lock held. NEVER |
| 519 | * access this list directly from a driver. |
| 520 | */ |
| 521 | struct list_head __devices; |
| 522 | struct list_head __targets; |
| 523 | |
| 524 | struct scsi_host_cmd_pool *cmd_pool; |
| 525 | spinlock_t free_list_lock; |
| 526 | struct list_head free_list; /* backup store of cmd structs */ |
| 527 | struct list_head starved_list; |
| 528 | |
| 529 | spinlock_t default_lock; |
| 530 | spinlock_t *host_lock; |
| 531 | |
| 532 | struct mutex scan_mutex;/* serialize scanning activity */ |
| 533 | |
| 534 | struct list_head eh_cmd_q; |
| 535 | struct task_struct * ehandler; /* Error recovery thread. */ |
| 536 | struct completion * eh_action; /* Wait for specific actions on the |
| 537 | host. */ |
| 538 | wait_queue_head_t host_wait; |
| 539 | struct scsi_host_template *hostt; |
| 540 | struct scsi_transport_template *transportt; |
| 541 | |
| 542 | /* |
| 543 | * Area to keep a shared tag map (if needed, will be |
| 544 | * NULL if not). |
| 545 | */ |
| 546 | struct blk_queue_tag *bqt; |
| 547 | |
| 548 | /* |
| 549 | * The following two fields are protected with host_lock; |
| 550 | * however, eh routines can safely access during eh processing |
| 551 | * without acquiring the lock. |
| 552 | */ |
| 553 | unsigned int host_busy; /* commands actually active on low-level */ |
| 554 | unsigned int host_failed; /* commands that failed. */ |
| 555 | unsigned int host_eh_scheduled; /* EH scheduled without command */ |
| 556 | |
| 557 | unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ |
| 558 | int resetting; /* if set, it means that last_reset is a valid value */ |
| 559 | unsigned long last_reset; |
| 560 | |
| 561 | /* |
| 562 | * These three parameters can be used to allow for wide scsi, |
| 563 | * and for host adapters that support multiple busses |
| 564 | * The first two should be set to 1 more than the actual max id |
| 565 | * or lun (i.e. 8 for normal systems). |
| 566 | */ |
| 567 | unsigned int max_id; |
| 568 | unsigned int max_lun; |
| 569 | unsigned int max_channel; |
| 570 | |
| 571 | /* |
| 572 | * This is a unique identifier that must be assigned so that we |
| 573 | * have some way of identifying each detected host adapter properly |
| 574 | * and uniquely. For hosts that do not support more than one card |
| 575 | * in the system at one time, this does not need to be set. It is |
| 576 | * initialized to 0 in scsi_register. |
| 577 | */ |
| 578 | unsigned int unique_id; |
| 579 | |
| 580 | /* |
| 581 | * The maximum length of SCSI commands that this host can accept. |
| 582 | * Probably 12 for most host adapters, but could be 16 for others. |
| 583 | * or 260 if the driver supports variable length cdbs. |
| 584 | * For drivers that don't set this field, a value of 12 is |
| 585 | * assumed. |
| 586 | */ |
| 587 | unsigned short max_cmd_len; |
| 588 | |
| 589 | int this_id; |
| 590 | int can_queue; |
| 591 | short cmd_per_lun; |
| 592 | short unsigned int sg_tablesize; |
| 593 | short unsigned int max_sectors; |
| 594 | unsigned long dma_boundary; |
| 595 | /* |
| 596 | * Used to assign serial numbers to the cmds. |
| 597 | * Protected by the host lock. |
| 598 | */ |
| 599 | unsigned long cmd_serial_number; |
| 600 | |
| 601 | unsigned active_mode:2; |
| 602 | unsigned unchecked_isa_dma:1; |
| 603 | unsigned use_clustering:1; |
| 604 | unsigned use_blk_tcq:1; |
| 605 | |
| 606 | /* |
| 607 | * Host has requested that no further requests come through for the |
| 608 | * time being. |
| 609 | */ |
| 610 | unsigned host_self_blocked:1; |
| 611 | |
| 612 | /* |
| 613 | * Host uses correct SCSI ordering not PC ordering. The bit is |
| 614 | * set for the minority of drivers whose authors actually read |
| 615 | * the spec ;). |
| 616 | */ |
| 617 | unsigned reverse_ordering:1; |
| 618 | |
| 619 | /* |
| 620 | * Ordered write support |
| 621 | */ |
| 622 | unsigned ordered_tag:1; |
| 623 | |
| 624 | /* Task mgmt function in progress */ |
| 625 | unsigned tmf_in_progress:1; |
| 626 | |
| 627 | /* Asynchronous scan in progress */ |
| 628 | unsigned async_scan:1; |
| 629 | |
| 630 | /* |
| 631 | * Optional work queue to be utilized by the transport |
| 632 | */ |
| 633 | char work_q_name[20]; |
| 634 | struct workqueue_struct *work_q; |
| 635 | |
| 636 | /* |
| 637 | * Host has rejected a command because it was busy. |
| 638 | */ |
| 639 | unsigned int host_blocked; |
| 640 | |
| 641 | /* |
| 642 | * Value host_blocked counts down from |
| 643 | */ |
| 644 | unsigned int max_host_blocked; |
| 645 | |
| 646 | /* Protection Information */ |
| 647 | unsigned int prot_capabilities; |
| 648 | unsigned char prot_guard_type; |
| 649 | |
| 650 | /* |
| 651 | * q used for scsi_tgt msgs, async events or any other requests that |
| 652 | * need to be processed in userspace |
| 653 | */ |
| 654 | struct request_queue *uspace_req_q; |
| 655 | |
| 656 | /* legacy crap */ |
| 657 | unsigned long base; |
| 658 | unsigned long io_port; |
| 659 | unsigned char n_io_port; |
| 660 | unsigned char dma_channel; |
| 661 | unsigned int irq; |
| 662 | |
| 663 | |
| 664 | enum scsi_host_state shost_state; |
| 665 | |
| 666 | /* ldm bits */ |
| 667 | struct device shost_gendev, shost_dev; |
| 668 | |
| 669 | /* |
| 670 | * List of hosts per template. |
| 671 | * |
| 672 | * This is only for use by scsi_module.c for legacy templates. |
| 673 | * For these access to it is synchronized implicitly by |
| 674 | * module_init/module_exit. |
| 675 | */ |
| 676 | struct list_head sht_legacy_list; |
| 677 | |
| 678 | /* |
| 679 | * Points to the transport data (if any) which is allocated |
| 680 | * separately |
| 681 | */ |
| 682 | void *shost_data; |
| 683 | |
| 684 | /* |
| 685 | * Points to the physical bus device we'd use to do DMA |
| 686 | * Needed just in case we have virtual hosts. |
| 687 | */ |
| 688 | struct device *dma_dev; |
| 689 | |
| 690 | /* |
| 691 | * We should ensure that this is aligned, both for better performance |
| 692 | * and also because some compilers (m68k) don't automatically force |
| 693 | * alignment to a long boundary. |
| 694 | */ |
| 695 | unsigned long hostdata[0] /* Used for storage of host specific stuff */ |
| 696 | __attribute__ ((aligned (sizeof(unsigned long)))); |
| 697 | }; |
| 698 | |
| 699 | #define class_to_shost(d) \ |
| 700 | container_of(d, struct Scsi_Host, shost_dev) |
| 701 | |
| 702 | #define shost_printk(prefix, shost, fmt, a...) \ |
| 703 | dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) |
| 704 | |
| 705 | static inline void *shost_priv(struct Scsi_Host *shost) |
| 706 | { |
| 707 | return (void *)shost->hostdata; |
| 708 | } |
| 709 | |
| 710 | int scsi_is_host_device(const struct device *); |
| 711 | |
| 712 | static inline struct Scsi_Host *dev_to_shost(struct device *dev) |
| 713 | { |
| 714 | while (!scsi_is_host_device(dev)) { |
| 715 | if (!dev->parent) |
| 716 | return NULL; |
| 717 | dev = dev->parent; |
| 718 | } |
| 719 | return container_of(dev, struct Scsi_Host, shost_gendev); |
| 720 | } |
| 721 | |
| 722 | static inline int scsi_host_in_recovery(struct Scsi_Host *shost) |
| 723 | { |
| 724 | return shost->shost_state == SHOST_RECOVERY || |
| 725 | shost->shost_state == SHOST_CANCEL_RECOVERY || |
| 726 | shost->shost_state == SHOST_DEL_RECOVERY || |
| 727 | shost->tmf_in_progress; |
| 728 | } |
| 729 | |
| 730 | extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); |
| 731 | extern void scsi_flush_work(struct Scsi_Host *); |
| 732 | |
| 733 | extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); |
| 734 | extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, |
| 735 | struct device *, |
| 736 | struct device *); |
| 737 | extern void scsi_scan_host(struct Scsi_Host *); |
| 738 | extern void scsi_rescan_device(struct device *); |
| 739 | extern void scsi_remove_host(struct Scsi_Host *); |
| 740 | extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); |
| 741 | extern void scsi_host_put(struct Scsi_Host *t); |
| 742 | extern struct Scsi_Host *scsi_host_lookup(unsigned short); |
| 743 | extern const char *scsi_host_state_name(enum scsi_host_state); |
| 744 | |
| 745 | extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *); |
| 746 | |
| 747 | static inline int __must_check scsi_add_host(struct Scsi_Host *host, |
| 748 | struct device *dev) |
| 749 | { |
| 750 | return scsi_add_host_with_dma(host, dev, dev); |
| 751 | } |
| 752 | |
| 753 | static inline struct device *scsi_get_device(struct Scsi_Host *shost) |
| 754 | { |
| 755 | return shost->shost_gendev.parent; |
| 756 | } |
| 757 | |
| 758 | /** |
| 759 | * scsi_host_scan_allowed - Is scanning of this host allowed |
| 760 | * @shost: Pointer to Scsi_Host. |
| 761 | **/ |
| 762 | static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) |
| 763 | { |
| 764 | return shost->shost_state == SHOST_RUNNING; |
| 765 | } |
| 766 | |
| 767 | extern void scsi_unblock_requests(struct Scsi_Host *); |
| 768 | extern void scsi_block_requests(struct Scsi_Host *); |
| 769 | |
| 770 | struct class_container; |
| 771 | |
| 772 | extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost, |
| 773 | void (*) (struct request_queue *)); |
| 774 | /* |
| 775 | * These two functions are used to allocate and free a pseudo device |
| 776 | * which will connect to the host adapter itself rather than any |
| 777 | * physical device. You must deallocate when you are done with the |
| 778 | * thing. This physical pseudo-device isn't real and won't be available |
| 779 | * from any high-level drivers. |
| 780 | */ |
| 781 | extern void scsi_free_host_dev(struct scsi_device *); |
| 782 | extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); |
| 783 | |
| 784 | /* |
| 785 | * DIF defines the exchange of protection information between |
| 786 | * initiator and SBC block device. |
| 787 | * |
| 788 | * DIX defines the exchange of protection information between OS and |
| 789 | * initiator. |
| 790 | */ |
| 791 | enum scsi_host_prot_capabilities { |
| 792 | SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ |
| 793 | SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ |
| 794 | SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ |
| 795 | |
| 796 | SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ |
| 797 | SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ |
| 798 | SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ |
| 799 | SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ |
| 800 | }; |
| 801 | |
| 802 | /* |
| 803 | * SCSI hosts which support the Data Integrity Extensions must |
| 804 | * indicate their capabilities by setting the prot_capabilities using |
| 805 | * this call. |
| 806 | */ |
| 807 | static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) |
| 808 | { |
| 809 | shost->prot_capabilities = mask; |
| 810 | } |
| 811 | |
| 812 | static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) |
| 813 | { |
| 814 | return shost->prot_capabilities; |
| 815 | } |
| 816 | |
| 817 | static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) |
| 818 | { |
| 819 | static unsigned char cap[] = { 0, |
| 820 | SHOST_DIF_TYPE1_PROTECTION, |
| 821 | SHOST_DIF_TYPE2_PROTECTION, |
| 822 | SHOST_DIF_TYPE3_PROTECTION }; |
| 823 | |
| 824 | return shost->prot_capabilities & cap[target_type] ? target_type : 0; |
| 825 | } |
| 826 | |
| 827 | static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) |
| 828 | { |
| 829 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
| 830 | static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, |
| 831 | SHOST_DIX_TYPE1_PROTECTION, |
| 832 | SHOST_DIX_TYPE2_PROTECTION, |
| 833 | SHOST_DIX_TYPE3_PROTECTION }; |
| 834 | |
| 835 | return shost->prot_capabilities & cap[target_type]; |
| 836 | #endif |
| 837 | return 0; |
| 838 | } |
| 839 | |
| 840 | /* |
| 841 | * All DIX-capable initiators must support the T10-mandated CRC |
| 842 | * checksum. Controllers can optionally implement the IP checksum |
| 843 | * scheme which has much lower impact on system performance. Note |
| 844 | * that the main rationale for the checksum is to match integrity |
| 845 | * metadata with data. Detecting bit errors are a job for ECC memory |
| 846 | * and buses. |
| 847 | */ |
| 848 | |
| 849 | enum scsi_host_guard_type { |
| 850 | SHOST_DIX_GUARD_CRC = 1 << 0, |
| 851 | SHOST_DIX_GUARD_IP = 1 << 1, |
| 852 | }; |
| 853 | |
| 854 | static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) |
| 855 | { |
| 856 | shost->prot_guard_type = type; |
| 857 | } |
| 858 | |
| 859 | static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) |
| 860 | { |
| 861 | return shost->prot_guard_type; |
| 862 | } |
| 863 | |
| 864 | /* legacy interfaces */ |
| 865 | extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int); |
| 866 | extern void scsi_unregister(struct Scsi_Host *); |
| 867 | extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); |
| 868 | |
| 869 | #endif /* _SCSI_SCSI_HOST_H */ |