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 enum { 47 SCSI_QDEPTH_DEFAULT, /* default requested change, e.g. from sysfs */ 48 SCSI_QDEPTH_QFULL, /* scsi-ml requested due to queue full */ 49 SCSI_QDEPTH_RAMP_UP, /* scsi-ml requested due to threshhold event */ 50 }; 51 52 struct scsi_host_template { 53 struct module *module; 54 const char *name; 55 56 /* 57 * Used to initialize old-style drivers. For new-style drivers 58 * just perform all work in your module initialization function. 59 * 60 * Status: OBSOLETE 61 */ 62 int (* detect)(struct scsi_host_template *); 63 64 /* 65 * Used as unload callback for hosts with old-style drivers. 66 * 67 * Status: OBSOLETE 68 */ 69 int (* release)(struct Scsi_Host *); 70 71 /* 72 * The info function will return whatever useful information the 73 * developer sees fit. If not provided, then the name field will 74 * be used instead. 75 * 76 * Status: OPTIONAL 77 */ 78 const char *(* info)(struct Scsi_Host *); 79 80 /* 81 * Ioctl interface 82 * 83 * Status: OPTIONAL 84 */ 85 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg); 86 87 88 #ifdef CONFIG_COMPAT 89 /* 90 * Compat handler. Handle 32bit ABI. 91 * When unknown ioctl is passed return -ENOIOCTLCMD. 92 * 93 * Status: OPTIONAL 94 */ 95 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg); 96 #endif 97 98 /* 99 * The queuecommand function is used to queue up a scsi 100 * command block to the LLDD. When the driver finished 101 * processing the command the done callback is invoked. 102 * 103 * If queuecommand returns 0, then the HBA has accepted the 104 * command. The done() function must be called on the command 105 * when the driver has finished with it. (you may call done on the 106 * command before queuecommand returns, but in this case you 107 * *must* return 0 from queuecommand). 108 * 109 * Queuecommand may also reject the command, in which case it may 110 * not touch the command and must not call done() for it. 111 * 112 * There are two possible rejection returns: 113 * 114 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 115 * allow commands to other devices serviced by this host. 116 * 117 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 118 * host temporarily. 119 * 120 * For compatibility, any other non-zero return is treated the 121 * same as SCSI_MLQUEUE_HOST_BUSY. 122 * 123 * NOTE: "temporarily" means either until the next command for# 124 * this device/host completes, or a period of time determined by 125 * I/O pressure in the system if there are no other outstanding 126 * commands. 127 * 128 * STATUS: REQUIRED 129 */ 130 int (* queuecommand)(struct scsi_cmnd *, 131 void (*done)(struct scsi_cmnd *)); 132 133 /* 134 * The transfer functions are used to queue a scsi command to 135 * the LLD. When the driver is finished processing the command 136 * the done callback is invoked. 137 * 138 * This is called to inform the LLD to transfer 139 * scsi_bufflen(cmd) bytes. scsi_sg_count(cmd) speciefies the 140 * number of scatterlist entried in the command and 141 * scsi_sglist(cmd) returns the scatterlist. 142 * 143 * return values: see queuecommand 144 * 145 * If the LLD accepts the cmd, it should set the result to an 146 * appropriate value when completed before calling the done function. 147 * 148 * STATUS: REQUIRED FOR TARGET DRIVERS 149 */ 150 /* TODO: rename */ 151 int (* transfer_response)(struct scsi_cmnd *, 152 void (*done)(struct scsi_cmnd *)); 153 154 /* 155 * This is an error handling strategy routine. You don't need to 156 * define one of these if you don't want to - there is a default 157 * routine that is present that should work in most cases. For those 158 * driver authors that have the inclination and ability to write their 159 * own strategy routine, this is where it is specified. Note - the 160 * strategy routine is *ALWAYS* run in the context of the kernel eh 161 * thread. Thus you are guaranteed to *NOT* be in an interrupt 162 * handler when you execute this, and you are also guaranteed to 163 * *NOT* have any other commands being queued while you are in the 164 * strategy routine. When you return from this function, operations 165 * return to normal. 166 * 167 * See scsi_error.c scsi_unjam_host for additional comments about 168 * what this function should and should not be attempting to do. 169 * 170 * Status: REQUIRED (at least one of them) 171 */ 172 int (* eh_abort_handler)(struct scsi_cmnd *); 173 int (* eh_device_reset_handler)(struct scsi_cmnd *); 174 int (* eh_target_reset_handler)(struct scsi_cmnd *); 175 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 176 int (* eh_host_reset_handler)(struct scsi_cmnd *); 177 178 /* 179 * Before the mid layer attempts to scan for a new device where none 180 * currently exists, it will call this entry in your driver. Should 181 * your driver need to allocate any structs or perform any other init 182 * items in order to send commands to a currently unused target/lun 183 * combo, then this is where you can perform those allocations. This 184 * is specifically so that drivers won't have to perform any kind of 185 * "is this a new device" checks in their queuecommand routine, 186 * thereby making the hot path a bit quicker. 187 * 188 * Return values: 0 on success, non-0 on failure 189 * 190 * Deallocation: If we didn't find any devices at this ID, you will 191 * get an immediate call to slave_destroy(). If we find something 192 * here then you will get a call to slave_configure(), then the 193 * device will be used for however long it is kept around, then when 194 * the device is removed from the system (or * possibly at reboot 195 * time), you will then get a call to slave_destroy(). This is 196 * assuming you implement slave_configure and slave_destroy. 197 * However, if you allocate memory and hang it off the device struct, 198 * then you must implement the slave_destroy() routine at a minimum 199 * in order to avoid leaking memory 200 * each time a device is tore down. 201 * 202 * Status: OPTIONAL 203 */ 204 int (* slave_alloc)(struct scsi_device *); 205 206 /* 207 * Once the device has responded to an INQUIRY and we know the 208 * device is online, we call into the low level driver with the 209 * struct scsi_device *. If the low level device driver implements 210 * this function, it *must* perform the task of setting the queue 211 * depth on the device. All other tasks are optional and depend 212 * on what the driver supports and various implementation details. 213 * 214 * Things currently recommended to be handled at this time include: 215 * 216 * 1. Setting the device queue depth. Proper setting of this is 217 * described in the comments for scsi_adjust_queue_depth. 218 * 2. Determining if the device supports the various synchronous 219 * negotiation protocols. The device struct will already have 220 * responded to INQUIRY and the results of the standard items 221 * will have been shoved into the various device flag bits, eg. 222 * device->sdtr will be true if the device supports SDTR messages. 223 * 3. Allocating command structs that the device will need. 224 * 4. Setting the default timeout on this device (if needed). 225 * 5. Anything else the low level driver might want to do on a device 226 * specific setup basis... 227 * 6. Return 0 on success, non-0 on error. The device will be marked 228 * as offline on error so that no access will occur. If you return 229 * non-0, your slave_destroy routine will never get called for this 230 * device, so don't leave any loose memory hanging around, clean 231 * up after yourself before returning non-0 232 * 233 * Status: OPTIONAL 234 */ 235 int (* slave_configure)(struct scsi_device *); 236 237 /* 238 * Immediately prior to deallocating the device and after all activity 239 * has ceased the mid layer calls this point so that the low level 240 * driver may completely detach itself from the scsi device and vice 241 * versa. The low level driver is responsible for freeing any memory 242 * it allocated in the slave_alloc or slave_configure calls. 243 * 244 * Status: OPTIONAL 245 */ 246 void (* slave_destroy)(struct scsi_device *); 247 248 /* 249 * Before the mid layer attempts to scan for a new device attached 250 * to a target where no target currently exists, it will call this 251 * entry in your driver. Should your driver need to allocate any 252 * structs or perform any other init items in order to send commands 253 * to a currently unused target, then this is where you can perform 254 * those allocations. 255 * 256 * Return values: 0 on success, non-0 on failure 257 * 258 * Status: OPTIONAL 259 */ 260 int (* target_alloc)(struct scsi_target *); 261 262 /* 263 * Immediately prior to deallocating the target structure, and 264 * after all activity to attached scsi devices has ceased, the 265 * midlayer calls this point so that the driver may deallocate 266 * and terminate any references to the target. 267 * 268 * Status: OPTIONAL 269 */ 270 void (* target_destroy)(struct scsi_target *); 271 272 /* 273 * If a host has the ability to discover targets on its own instead 274 * of scanning the entire bus, it can fill in this function and 275 * call scsi_scan_host(). This function will be called periodically 276 * until it returns 1 with the scsi_host and the elapsed time of 277 * the scan in jiffies. 278 * 279 * Status: OPTIONAL 280 */ 281 int (* scan_finished)(struct Scsi_Host *, unsigned long); 282 283 /* 284 * If the host wants to be called before the scan starts, but 285 * after the midlayer has set up ready for the scan, it can fill 286 * in this function. 287 * 288 * Status: OPTIONAL 289 */ 290 void (* scan_start)(struct Scsi_Host *); 291 292 /* 293 * Fill in this function to allow the queue depth of this host 294 * to be changeable (on a per device basis). Returns either 295 * the current queue depth setting (may be different from what 296 * was passed in) or an error. An error should only be 297 * returned if the requested depth is legal but the driver was 298 * unable to set it. If the requested depth is illegal, the 299 * driver should set and return the closest legal queue depth. 300 * 301 * Status: OPTIONAL 302 */ 303 int (* change_queue_depth)(struct scsi_device *, int, int); 304 305 /* 306 * Fill in this function to allow the changing of tag types 307 * (this also allows the enabling/disabling of tag command 308 * queueing). An error should only be returned if something 309 * went wrong in the driver while trying to set the tag type. 310 * If the driver doesn't support the requested tag type, then 311 * it should set the closest type it does support without 312 * returning an error. Returns the actual tag type set. 313 * 314 * Status: OPTIONAL 315 */ 316 int (* change_queue_type)(struct scsi_device *, int); 317 318 /* 319 * This function determines the BIOS parameters for a given 320 * harddisk. These tend to be numbers that are made up by 321 * the host adapter. Parameters: 322 * size, device, list (heads, sectors, cylinders) 323 * 324 * Status: OPTIONAL 325 */ 326 int (* bios_param)(struct scsi_device *, struct block_device *, 327 sector_t, int []); 328 329 /* 330 * This function is called when one or more partitions on the 331 * device reach beyond the end of the device. 332 * 333 * Status: OPTIONAL 334 */ 335 void (*unlock_native_capacity)(struct scsi_device *); 336 337 /* 338 * Can be used to export driver statistics and other infos to the 339 * world outside the kernel ie. userspace and it also provides an 340 * interface to feed the driver with information. 341 * 342 * Status: OBSOLETE 343 */ 344 int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int); 345 346 /* 347 * This is an optional routine that allows the transport to become 348 * involved when a scsi io timer fires. The return value tells the 349 * timer routine how to finish the io timeout handling: 350 * EH_HANDLED: I fixed the error, please complete the command 351 * EH_RESET_TIMER: I need more time, reset the timer and 352 * begin counting again 353 * EH_NOT_HANDLED Begin normal error recovery 354 * 355 * Status: OPTIONAL 356 */ 357 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 358 359 /* 360 * Name of proc directory 361 */ 362 const char *proc_name; 363 364 /* 365 * Used to store the procfs directory if a driver implements the 366 * proc_info method. 367 */ 368 struct proc_dir_entry *proc_dir; 369 370 /* 371 * This determines if we will use a non-interrupt driven 372 * or an interrupt driven scheme. It is set to the maximum number 373 * of simultaneous commands a given host adapter will accept. 374 */ 375 int can_queue; 376 377 /* 378 * In many instances, especially where disconnect / reconnect are 379 * supported, our host also has an ID on the SCSI bus. If this is 380 * the case, then it must be reserved. Please set this_id to -1 if 381 * your setup is in single initiator mode, and the host lacks an 382 * ID. 383 */ 384 int this_id; 385 386 /* 387 * This determines the degree to which the host adapter is capable 388 * of scatter-gather. 389 */ 390 unsigned short sg_tablesize; 391 unsigned short sg_prot_tablesize; 392 393 /* 394 * Set this if the host adapter has limitations beside segment count. 395 */ 396 unsigned short max_sectors; 397 398 /* 399 * DMA scatter gather segment boundary limit. A segment crossing this 400 * boundary will be split in two. 401 */ 402 unsigned long dma_boundary; 403 404 /* 405 * This specifies "machine infinity" for host templates which don't 406 * limit the transfer size. Note this limit represents an absolute 407 * maximum, and may be over the transfer limits allowed for 408 * individual devices (e.g. 256 for SCSI-1). 409 */ 410 #define SCSI_DEFAULT_MAX_SECTORS 1024 411 412 /* 413 * True if this host adapter can make good use of linked commands. 414 * This will allow more than one command to be queued to a given 415 * unit on a given host. Set this to the maximum number of command 416 * blocks to be provided for each device. Set this to 1 for one 417 * command block per lun, 2 for two, etc. Do not set this to 0. 418 * You should make sure that the host adapter will do the right thing 419 * before you try setting this above 1. 420 */ 421 short cmd_per_lun; 422 423 /* 424 * present contains counter indicating how many boards of this 425 * type were found when we did the scan. 426 */ 427 unsigned char present; 428 429 /* 430 * This specifies the mode that a LLD supports. 431 */ 432 unsigned supported_mode:2; 433 434 /* 435 * True if this host adapter uses unchecked DMA onto an ISA bus. 436 */ 437 unsigned unchecked_isa_dma:1; 438 439 /* 440 * True if this host adapter can make good use of clustering. 441 * I originally thought that if the tablesize was large that it 442 * was a waste of CPU cycles to prepare a cluster list, but 443 * it works out that the Buslogic is faster if you use a smaller 444 * number of segments (i.e. use clustering). I guess it is 445 * inefficient. 446 */ 447 unsigned use_clustering:1; 448 449 /* 450 * True for emulated SCSI host adapters (e.g. ATAPI). 451 */ 452 unsigned emulated:1; 453 454 /* 455 * True if the low-level driver performs its own reset-settle delays. 456 */ 457 unsigned skip_settle_delay:1; 458 459 /* 460 * True if we are using ordered write support. 461 */ 462 unsigned ordered_tag:1; 463 464 /* 465 * Countdown for host blocking with no commands outstanding. 466 */ 467 unsigned int max_host_blocked; 468 469 /* 470 * Default value for the blocking. If the queue is empty, 471 * host_blocked counts down in the request_fn until it restarts 472 * host operations as zero is reached. 473 * 474 * FIXME: This should probably be a value in the template 475 */ 476 #define SCSI_DEFAULT_HOST_BLOCKED 7 477 478 /* 479 * Pointer to the sysfs class properties for this host, NULL terminated. 480 */ 481 struct device_attribute **shost_attrs; 482 483 /* 484 * Pointer to the SCSI device properties for this host, NULL terminated. 485 */ 486 struct device_attribute **sdev_attrs; 487 488 /* 489 * List of hosts per template. 490 * 491 * This is only for use by scsi_module.c for legacy templates. 492 * For these access to it is synchronized implicitly by 493 * module_init/module_exit. 494 */ 495 struct list_head legacy_hosts; 496 497 /* 498 * Vendor Identifier associated with the host 499 * 500 * Note: When specifying vendor_id, be sure to read the 501 * Vendor Type and ID formatting requirements specified in 502 * scsi_netlink.h 503 */ 504 u64 vendor_id; 505 }; 506 507 /* 508 * shost state: If you alter this, you also need to alter scsi_sysfs.c 509 * (for the ascii descriptions) and the state model enforcer: 510 * scsi_host_set_state() 511 */ 512 enum scsi_host_state { 513 SHOST_CREATED = 1, 514 SHOST_RUNNING, 515 SHOST_CANCEL, 516 SHOST_DEL, 517 SHOST_RECOVERY, 518 SHOST_CANCEL_RECOVERY, 519 SHOST_DEL_RECOVERY, 520 }; 521 522 struct Scsi_Host { 523 /* 524 * __devices is protected by the host_lock, but you should 525 * usually use scsi_device_lookup / shost_for_each_device 526 * to access it and don't care about locking yourself. 527 * In the rare case of beeing in irq context you can use 528 * their __ prefixed variants with the lock held. NEVER 529 * access this list directly from a driver. 530 */ 531 struct list_head __devices; 532 struct list_head __targets; 533 534 struct scsi_host_cmd_pool *cmd_pool; 535 spinlock_t free_list_lock; 536 struct list_head free_list; /* backup store of cmd structs */ 537 struct list_head starved_list; 538 539 spinlock_t default_lock; 540 spinlock_t *host_lock; 541 542 struct mutex scan_mutex;/* serialize scanning activity */ 543 544 struct list_head eh_cmd_q; 545 struct task_struct * ehandler; /* Error recovery thread. */ 546 struct completion * eh_action; /* Wait for specific actions on the 547 host. */ 548 wait_queue_head_t host_wait; 549 struct scsi_host_template *hostt; 550 struct scsi_transport_template *transportt; 551 552 /* 553 * Area to keep a shared tag map (if needed, will be 554 * NULL if not). 555 */ 556 struct blk_queue_tag *bqt; 557 558 /* 559 * The following two fields are protected with host_lock; 560 * however, eh routines can safely access during eh processing 561 * without acquiring the lock. 562 */ 563 unsigned int host_busy; /* commands actually active on low-level */ 564 unsigned int host_failed; /* commands that failed. */ 565 unsigned int host_eh_scheduled; /* EH scheduled without command */ 566 567 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 568 int resetting; /* if set, it means that last_reset is a valid value */ 569 unsigned long last_reset; 570 571 /* 572 * These three parameters can be used to allow for wide scsi, 573 * and for host adapters that support multiple busses 574 * The first two should be set to 1 more than the actual max id 575 * or lun (i.e. 8 for normal systems). 576 */ 577 unsigned int max_id; 578 unsigned int max_lun; 579 unsigned int max_channel; 580 581 /* 582 * This is a unique identifier that must be assigned so that we 583 * have some way of identifying each detected host adapter properly 584 * and uniquely. For hosts that do not support more than one card 585 * in the system at one time, this does not need to be set. It is 586 * initialized to 0 in scsi_register. 587 */ 588 unsigned int unique_id; 589 590 /* 591 * The maximum length of SCSI commands that this host can accept. 592 * Probably 12 for most host adapters, but could be 16 for others. 593 * or 260 if the driver supports variable length cdbs. 594 * For drivers that don't set this field, a value of 12 is 595 * assumed. 596 */ 597 unsigned short max_cmd_len; 598 599 int this_id; 600 int can_queue; 601 short cmd_per_lun; 602 short unsigned int sg_tablesize; 603 short unsigned int sg_prot_tablesize; 604 short unsigned int max_sectors; 605 unsigned long dma_boundary; 606 /* 607 * Used to assign serial numbers to the cmds. 608 * Protected by the host lock. 609 */ 610 unsigned long cmd_serial_number; 611 612 unsigned active_mode:2; 613 unsigned unchecked_isa_dma:1; 614 unsigned use_clustering:1; 615 unsigned use_blk_tcq:1; 616 617 /* 618 * Host has requested that no further requests come through for the 619 * time being. 620 */ 621 unsigned host_self_blocked:1; 622 623 /* 624 * Host uses correct SCSI ordering not PC ordering. The bit is 625 * set for the minority of drivers whose authors actually read 626 * the spec ;). 627 */ 628 unsigned reverse_ordering:1; 629 630 /* 631 * Ordered write support 632 */ 633 unsigned ordered_tag:1; 634 635 /* Task mgmt function in progress */ 636 unsigned tmf_in_progress:1; 637 638 /* Asynchronous scan in progress */ 639 unsigned async_scan:1; 640 641 /* 642 * Optional work queue to be utilized by the transport 643 */ 644 char work_q_name[20]; 645 struct workqueue_struct *work_q; 646 647 /* 648 * Host has rejected a command because it was busy. 649 */ 650 unsigned int host_blocked; 651 652 /* 653 * Value host_blocked counts down from 654 */ 655 unsigned int max_host_blocked; 656 657 /* Protection Information */ 658 unsigned int prot_capabilities; 659 unsigned char prot_guard_type; 660 661 /* 662 * q used for scsi_tgt msgs, async events or any other requests that 663 * need to be processed in userspace 664 */ 665 struct request_queue *uspace_req_q; 666 667 /* legacy crap */ 668 unsigned long base; 669 unsigned long io_port; 670 unsigned char n_io_port; 671 unsigned char dma_channel; 672 unsigned int irq; 673 674 675 enum scsi_host_state shost_state; 676 677 /* ldm bits */ 678 struct device shost_gendev, shost_dev; 679 680 /* 681 * List of hosts per template. 682 * 683 * This is only for use by scsi_module.c for legacy templates. 684 * For these access to it is synchronized implicitly by 685 * module_init/module_exit. 686 */ 687 struct list_head sht_legacy_list; 688 689 /* 690 * Points to the transport data (if any) which is allocated 691 * separately 692 */ 693 void *shost_data; 694 695 /* 696 * Points to the physical bus device we'd use to do DMA 697 * Needed just in case we have virtual hosts. 698 */ 699 struct device *dma_dev; 700 701 /* 702 * We should ensure that this is aligned, both for better performance 703 * and also because some compilers (m68k) don't automatically force 704 * alignment to a long boundary. 705 */ 706 unsigned long hostdata[0] /* Used for storage of host specific stuff */ 707 __attribute__ ((aligned (sizeof(unsigned long)))); 708 }; 709 710 #define class_to_shost(d) \ 711 container_of(d, struct Scsi_Host, shost_dev) 712 713 #define shost_printk(prefix, shost, fmt, a...) \ 714 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 715 716 static inline void *shost_priv(struct Scsi_Host *shost) 717 { 718 return (void *)shost->hostdata; 719 } 720 721 int scsi_is_host_device(const struct device *); 722 723 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 724 { 725 while (!scsi_is_host_device(dev)) { 726 if (!dev->parent) 727 return NULL; 728 dev = dev->parent; 729 } 730 return container_of(dev, struct Scsi_Host, shost_gendev); 731 } 732 733 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 734 { 735 return shost->shost_state == SHOST_RECOVERY || 736 shost->shost_state == SHOST_CANCEL_RECOVERY || 737 shost->shost_state == SHOST_DEL_RECOVERY || 738 shost->tmf_in_progress; 739 } 740 741 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 742 extern void scsi_flush_work(struct Scsi_Host *); 743 744 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); 745 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 746 struct device *, 747 struct device *); 748 extern void scsi_scan_host(struct Scsi_Host *); 749 extern void scsi_rescan_device(struct device *); 750 extern void scsi_remove_host(struct Scsi_Host *); 751 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 752 extern void scsi_host_put(struct Scsi_Host *t); 753 extern struct Scsi_Host *scsi_host_lookup(unsigned short); 754 extern const char *scsi_host_state_name(enum scsi_host_state); 755 756 extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *); 757 758 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 759 struct device *dev) 760 { 761 return scsi_add_host_with_dma(host, dev, dev); 762 } 763 764 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 765 { 766 return shost->shost_gendev.parent; 767 } 768 769 /** 770 * scsi_host_scan_allowed - Is scanning of this host allowed 771 * @shost: Pointer to Scsi_Host. 772 **/ 773 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 774 { 775 return shost->shost_state == SHOST_RUNNING; 776 } 777 778 extern void scsi_unblock_requests(struct Scsi_Host *); 779 extern void scsi_block_requests(struct Scsi_Host *); 780 781 struct class_container; 782 783 extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost, 784 void (*) (struct request_queue *)); 785 /* 786 * These two functions are used to allocate and free a pseudo device 787 * which will connect to the host adapter itself rather than any 788 * physical device. You must deallocate when you are done with the 789 * thing. This physical pseudo-device isn't real and won't be available 790 * from any high-level drivers. 791 */ 792 extern void scsi_free_host_dev(struct scsi_device *); 793 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); 794 795 /* 796 * DIF defines the exchange of protection information between 797 * initiator and SBC block device. 798 * 799 * DIX defines the exchange of protection information between OS and 800 * initiator. 801 */ 802 enum scsi_host_prot_capabilities { 803 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 804 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 805 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 806 807 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 808 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 809 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 810 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 811 }; 812 813 /* 814 * SCSI hosts which support the Data Integrity Extensions must 815 * indicate their capabilities by setting the prot_capabilities using 816 * this call. 817 */ 818 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 819 { 820 shost->prot_capabilities = mask; 821 } 822 823 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 824 { 825 return shost->prot_capabilities; 826 } 827 828 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 829 { 830 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 831 } 832 833 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 834 { 835 static unsigned char cap[] = { 0, 836 SHOST_DIF_TYPE1_PROTECTION, 837 SHOST_DIF_TYPE2_PROTECTION, 838 SHOST_DIF_TYPE3_PROTECTION }; 839 840 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 841 } 842 843 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 844 { 845 #if defined(CONFIG_BLK_DEV_INTEGRITY) 846 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 847 SHOST_DIX_TYPE1_PROTECTION, 848 SHOST_DIX_TYPE2_PROTECTION, 849 SHOST_DIX_TYPE3_PROTECTION }; 850 851 return shost->prot_capabilities & cap[target_type]; 852 #endif 853 return 0; 854 } 855 856 /* 857 * All DIX-capable initiators must support the T10-mandated CRC 858 * checksum. Controllers can optionally implement the IP checksum 859 * scheme which has much lower impact on system performance. Note 860 * that the main rationale for the checksum is to match integrity 861 * metadata with data. Detecting bit errors are a job for ECC memory 862 * and buses. 863 */ 864 865 enum scsi_host_guard_type { 866 SHOST_DIX_GUARD_CRC = 1 << 0, 867 SHOST_DIX_GUARD_IP = 1 << 1, 868 }; 869 870 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 871 { 872 shost->prot_guard_type = type; 873 } 874 875 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 876 { 877 return shost->prot_guard_type; 878 } 879 880 /* legacy interfaces */ 881 extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int); 882 extern void scsi_unregister(struct Scsi_Host *); 883 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 884 885 #endif /* _SCSI_SCSI_HOST_H */ 886