1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _SCSI_SCSI_HOST_H 3#define _SCSI_SCSI_HOST_H 4 5#include <linux/device.h> 6#include <linux/list.h> 7#include <linux/types.h> 8#include <linux/workqueue.h> 9#include <linux/mutex.h> 10#include <linux/seq_file.h> 11#include <linux/blk-mq.h> 12#include <scsi/scsi.h> 13 14struct request_queue; 15struct block_device; 16struct completion; 17struct module; 18struct scsi_cmnd; 19struct scsi_device; 20struct scsi_host_cmd_pool; 21struct scsi_target; 22struct Scsi_Host; 23struct scsi_host_cmd_pool; 24struct scsi_transport_template; 25struct blk_queue_tags; 26 27 28/* 29 * The various choices mean: 30 * NONE: Self evident. Host adapter is not capable of scatter-gather. 31 * ALL: Means that the host adapter module can do scatter-gather, 32 * and that there is no limit to the size of the table to which 33 * we scatter/gather data. The value we set here is the maximum 34 * single element sglist. To use chained sglists, the adapter 35 * has to set a value beyond ALL (and correctly use the chain 36 * handling API. 37 * Anything else: Indicates the maximum number of chains that can be 38 * used in one scatter-gather request. 39 */ 40#define SG_NONE 0 41#define SG_ALL SG_CHUNK_SIZE 42 43#define MODE_UNKNOWN 0x00 44#define MODE_INITIATOR 0x01 45#define MODE_TARGET 0x02 46 47#define DISABLE_CLUSTERING 0 48#define ENABLE_CLUSTERING 1 49 50struct scsi_host_template { 51 struct module *module; 52 const char *name; 53 54 /* 55 * Used to initialize old-style drivers. For new-style drivers 56 * just perform all work in your module initialization function. 57 * 58 * Status: OBSOLETE 59 */ 60 int (* detect)(struct scsi_host_template *); 61 62 /* 63 * Used as unload callback for hosts with old-style drivers. 64 * 65 * Status: OBSOLETE 66 */ 67 int (* release)(struct Scsi_Host *); 68 69 /* 70 * The info function will return whatever useful information the 71 * developer sees fit. If not provided, then the name field will 72 * be used instead. 73 * 74 * Status: OPTIONAL 75 */ 76 const char *(* info)(struct Scsi_Host *); 77 78 /* 79 * Ioctl interface 80 * 81 * Status: OPTIONAL 82 */ 83 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg); 84 85 86#ifdef CONFIG_COMPAT 87 /* 88 * Compat handler. Handle 32bit ABI. 89 * When unknown ioctl is passed return -ENOIOCTLCMD. 90 * 91 * Status: OPTIONAL 92 */ 93 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg); 94#endif 95 96 /* 97 * The queuecommand function is used to queue up a scsi 98 * command block to the LLDD. When the driver finished 99 * processing the command the done callback is invoked. 100 * 101 * If queuecommand returns 0, then the HBA has accepted the 102 * command. The done() function must be called on the command 103 * when the driver has finished with it. (you may call done on the 104 * command before queuecommand returns, but in this case you 105 * *must* return 0 from queuecommand). 106 * 107 * Queuecommand may also reject the command, in which case it may 108 * not touch the command and must not call done() for it. 109 * 110 * There are two possible rejection returns: 111 * 112 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 113 * allow commands to other devices serviced by this host. 114 * 115 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 116 * host temporarily. 117 * 118 * For compatibility, any other non-zero return is treated the 119 * same as SCSI_MLQUEUE_HOST_BUSY. 120 * 121 * NOTE: "temporarily" means either until the next command for# 122 * this device/host completes, or a period of time determined by 123 * I/O pressure in the system if there are no other outstanding 124 * commands. 125 * 126 * STATUS: REQUIRED 127 */ 128 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); 129 130 /* 131 * This is an error handling strategy routine. You don't need to 132 * define one of these if you don't want to - there is a default 133 * routine that is present that should work in most cases. For those 134 * driver authors that have the inclination and ability to write their 135 * own strategy routine, this is where it is specified. Note - the 136 * strategy routine is *ALWAYS* run in the context of the kernel eh 137 * thread. Thus you are guaranteed to *NOT* be in an interrupt 138 * handler when you execute this, and you are also guaranteed to 139 * *NOT* have any other commands being queued while you are in the 140 * strategy routine. When you return from this function, operations 141 * return to normal. 142 * 143 * See scsi_error.c scsi_unjam_host for additional comments about 144 * what this function should and should not be attempting to do. 145 * 146 * Status: REQUIRED (at least one of them) 147 */ 148 int (* eh_abort_handler)(struct scsi_cmnd *); 149 int (* eh_device_reset_handler)(struct scsi_cmnd *); 150 int (* eh_target_reset_handler)(struct scsi_cmnd *); 151 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 152 int (* eh_host_reset_handler)(struct scsi_cmnd *); 153 154 /* 155 * Before the mid layer attempts to scan for a new device where none 156 * currently exists, it will call this entry in your driver. Should 157 * your driver need to allocate any structs or perform any other init 158 * items in order to send commands to a currently unused target/lun 159 * combo, then this is where you can perform those allocations. This 160 * is specifically so that drivers won't have to perform any kind of 161 * "is this a new device" checks in their queuecommand routine, 162 * thereby making the hot path a bit quicker. 163 * 164 * Return values: 0 on success, non-0 on failure 165 * 166 * Deallocation: If we didn't find any devices at this ID, you will 167 * get an immediate call to slave_destroy(). If we find something 168 * here then you will get a call to slave_configure(), then the 169 * device will be used for however long it is kept around, then when 170 * the device is removed from the system (or * possibly at reboot 171 * time), you will then get a call to slave_destroy(). This is 172 * assuming you implement slave_configure and slave_destroy. 173 * However, if you allocate memory and hang it off the device struct, 174 * then you must implement the slave_destroy() routine at a minimum 175 * in order to avoid leaking memory 176 * each time a device is tore down. 177 * 178 * Status: OPTIONAL 179 */ 180 int (* slave_alloc)(struct scsi_device *); 181 182 /* 183 * Once the device has responded to an INQUIRY and we know the 184 * device is online, we call into the low level driver with the 185 * struct scsi_device *. If the low level device driver implements 186 * this function, it *must* perform the task of setting the queue 187 * depth on the device. All other tasks are optional and depend 188 * on what the driver supports and various implementation details. 189 * 190 * Things currently recommended to be handled at this time include: 191 * 192 * 1. Setting the device queue depth. Proper setting of this is 193 * described in the comments for scsi_change_queue_depth. 194 * 2. Determining if the device supports the various synchronous 195 * negotiation protocols. The device struct will already have 196 * responded to INQUIRY and the results of the standard items 197 * will have been shoved into the various device flag bits, eg. 198 * device->sdtr will be true if the device supports SDTR messages. 199 * 3. Allocating command structs that the device will need. 200 * 4. Setting the default timeout on this device (if needed). 201 * 5. Anything else the low level driver might want to do on a device 202 * specific setup basis... 203 * 6. Return 0 on success, non-0 on error. The device will be marked 204 * as offline on error so that no access will occur. If you return 205 * non-0, your slave_destroy routine will never get called for this 206 * device, so don't leave any loose memory hanging around, clean 207 * up after yourself before returning non-0 208 * 209 * Status: OPTIONAL 210 */ 211 int (* slave_configure)(struct scsi_device *); 212 213 /* 214 * Immediately prior to deallocating the device and after all activity 215 * has ceased the mid layer calls this point so that the low level 216 * driver may completely detach itself from the scsi device and vice 217 * versa. The low level driver is responsible for freeing any memory 218 * it allocated in the slave_alloc or slave_configure calls. 219 * 220 * Status: OPTIONAL 221 */ 222 void (* slave_destroy)(struct scsi_device *); 223 224 /* 225 * Before the mid layer attempts to scan for a new device attached 226 * to a target where no target currently exists, it will call this 227 * entry in your driver. Should your driver need to allocate any 228 * structs or perform any other init items in order to send commands 229 * to a currently unused target, then this is where you can perform 230 * those allocations. 231 * 232 * Return values: 0 on success, non-0 on failure 233 * 234 * Status: OPTIONAL 235 */ 236 int (* target_alloc)(struct scsi_target *); 237 238 /* 239 * Immediately prior to deallocating the target structure, and 240 * after all activity to attached scsi devices has ceased, the 241 * midlayer calls this point so that the driver may deallocate 242 * and terminate any references to the target. 243 * 244 * Status: OPTIONAL 245 */ 246 void (* target_destroy)(struct scsi_target *); 247 248 /* 249 * If a host has the ability to discover targets on its own instead 250 * of scanning the entire bus, it can fill in this function and 251 * call scsi_scan_host(). This function will be called periodically 252 * until it returns 1 with the scsi_host and the elapsed time of 253 * the scan in jiffies. 254 * 255 * Status: OPTIONAL 256 */ 257 int (* scan_finished)(struct Scsi_Host *, unsigned long); 258 259 /* 260 * If the host wants to be called before the scan starts, but 261 * after the midlayer has set up ready for the scan, it can fill 262 * in this function. 263 * 264 * Status: OPTIONAL 265 */ 266 void (* scan_start)(struct Scsi_Host *); 267 268 /* 269 * Fill in this function to allow the queue depth of this host 270 * to be changeable (on a per device basis). Returns either 271 * the current queue depth setting (may be different from what 272 * was passed in) or an error. An error should only be 273 * returned if the requested depth is legal but the driver was 274 * unable to set it. If the requested depth is illegal, the 275 * driver should set and return the closest legal queue depth. 276 * 277 * Status: OPTIONAL 278 */ 279 int (* change_queue_depth)(struct scsi_device *, int); 280 281 /* 282 * This functions lets the driver expose the queue mapping 283 * to the block layer. 284 * 285 * Status: OPTIONAL 286 */ 287 int (* map_queues)(struct Scsi_Host *shost); 288 289 /* 290 * This function determines the BIOS parameters for a given 291 * harddisk. These tend to be numbers that are made up by 292 * the host adapter. Parameters: 293 * size, device, list (heads, sectors, cylinders) 294 * 295 * Status: OPTIONAL 296 */ 297 int (* bios_param)(struct scsi_device *, struct block_device *, 298 sector_t, int []); 299 300 /* 301 * This function is called when one or more partitions on the 302 * device reach beyond the end of the device. 303 * 304 * Status: OPTIONAL 305 */ 306 void (*unlock_native_capacity)(struct scsi_device *); 307 308 /* 309 * Can be used to export driver statistics and other infos to the 310 * world outside the kernel ie. userspace and it also provides an 311 * interface to feed the driver with information. 312 * 313 * Status: OBSOLETE 314 */ 315 int (*show_info)(struct seq_file *, struct Scsi_Host *); 316 int (*write_info)(struct Scsi_Host *, char *, int); 317 318 /* 319 * This is an optional routine that allows the transport to become 320 * involved when a scsi io timer fires. The return value tells the 321 * timer routine how to finish the io timeout handling: 322 * EH_HANDLED: I fixed the error, please complete the command 323 * EH_RESET_TIMER: I need more time, reset the timer and 324 * begin counting again 325 * EH_NOT_HANDLED Begin normal error recovery 326 * 327 * Status: OPTIONAL 328 */ 329 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 330 331 /* This is an optional routine that allows transport to initiate 332 * LLD adapter or firmware reset using sysfs attribute. 333 * 334 * Return values: 0 on success, -ve value on failure. 335 * 336 * Status: OPTIONAL 337 */ 338 339 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 340#define SCSI_ADAPTER_RESET 1 341#define SCSI_FIRMWARE_RESET 2 342 343 344 /* 345 * Name of proc directory 346 */ 347 const char *proc_name; 348 349 /* 350 * Used to store the procfs directory if a driver implements the 351 * show_info method. 352 */ 353 struct proc_dir_entry *proc_dir; 354 355 /* 356 * This determines if we will use a non-interrupt driven 357 * or an interrupt driven scheme. It is set to the maximum number 358 * of simultaneous commands a given host adapter will accept. 359 */ 360 int can_queue; 361 362 /* 363 * In many instances, especially where disconnect / reconnect are 364 * supported, our host also has an ID on the SCSI bus. If this is 365 * the case, then it must be reserved. Please set this_id to -1 if 366 * your setup is in single initiator mode, and the host lacks an 367 * ID. 368 */ 369 int this_id; 370 371 /* 372 * This determines the degree to which the host adapter is capable 373 * of scatter-gather. 374 */ 375 unsigned short sg_tablesize; 376 unsigned short sg_prot_tablesize; 377 378 /* 379 * Set this if the host adapter has limitations beside segment count. 380 */ 381 unsigned int max_sectors; 382 383 /* 384 * DMA scatter gather segment boundary limit. A segment crossing this 385 * boundary will be split in two. 386 */ 387 unsigned long dma_boundary; 388 389 /* 390 * This specifies "machine infinity" for host templates which don't 391 * limit the transfer size. Note this limit represents an absolute 392 * maximum, and may be over the transfer limits allowed for 393 * individual devices (e.g. 256 for SCSI-1). 394 */ 395#define SCSI_DEFAULT_MAX_SECTORS 1024 396 397 /* 398 * True if this host adapter can make good use of linked commands. 399 * This will allow more than one command to be queued to a given 400 * unit on a given host. Set this to the maximum number of command 401 * blocks to be provided for each device. Set this to 1 for one 402 * command block per lun, 2 for two, etc. Do not set this to 0. 403 * You should make sure that the host adapter will do the right thing 404 * before you try setting this above 1. 405 */ 406 short cmd_per_lun; 407 408 /* 409 * present contains counter indicating how many boards of this 410 * type were found when we did the scan. 411 */ 412 unsigned char present; 413 414 /* If use block layer to manage tags, this is tag allocation policy */ 415 int tag_alloc_policy; 416 417 /* 418 * Track QUEUE_FULL events and reduce queue depth on demand. 419 */ 420 unsigned track_queue_depth:1; 421 422 /* 423 * This specifies the mode that a LLD supports. 424 */ 425 unsigned supported_mode:2; 426 427 /* 428 * True if this host adapter uses unchecked DMA onto an ISA bus. 429 */ 430 unsigned unchecked_isa_dma:1; 431 432 /* 433 * True if this host adapter can make good use of clustering. 434 * I originally thought that if the tablesize was large that it 435 * was a waste of CPU cycles to prepare a cluster list, but 436 * it works out that the Buslogic is faster if you use a smaller 437 * number of segments (i.e. use clustering). I guess it is 438 * inefficient. 439 */ 440 unsigned use_clustering:1; 441 442 /* 443 * True for emulated SCSI host adapters (e.g. ATAPI). 444 */ 445 unsigned emulated:1; 446 447 /* 448 * True if the low-level driver performs its own reset-settle delays. 449 */ 450 unsigned skip_settle_delay:1; 451 452 /* True if the controller does not support WRITE SAME */ 453 unsigned no_write_same:1; 454 455 /* True if the low-level driver supports blk-mq only */ 456 unsigned force_blk_mq:1; 457 458 /* 459 * Countdown for host blocking with no commands outstanding. 460 */ 461 unsigned int max_host_blocked; 462 463 /* 464 * Default value for the blocking. If the queue is empty, 465 * host_blocked counts down in the request_fn until it restarts 466 * host operations as zero is reached. 467 * 468 * FIXME: This should probably be a value in the template 469 */ 470#define SCSI_DEFAULT_HOST_BLOCKED 7 471 472 /* 473 * Pointer to the sysfs class properties for this host, NULL terminated. 474 */ 475 struct device_attribute **shost_attrs; 476 477 /* 478 * Pointer to the SCSI device properties for this host, NULL terminated. 479 */ 480 struct device_attribute **sdev_attrs; 481 482 /* 483 * List of hosts per template. 484 * 485 * This is only for use by scsi_module.c for legacy templates. 486 * For these access to it is synchronized implicitly by 487 * module_init/module_exit. 488 */ 489 struct list_head legacy_hosts; 490 491 /* 492 * Vendor Identifier associated with the host 493 * 494 * Note: When specifying vendor_id, be sure to read the 495 * Vendor Type and ID formatting requirements specified in 496 * scsi_netlink.h 497 */ 498 u64 vendor_id; 499 500 /* 501 * Additional per-command data allocated for the driver. 502 */ 503 unsigned int cmd_size; 504 struct scsi_host_cmd_pool *cmd_pool; 505}; 506 507/* 508 * Temporary #define for host lock push down. Can be removed when all 509 * drivers have been updated to take advantage of unlocked 510 * queuecommand. 511 * 512 */ 513#define DEF_SCSI_QCMD(func_name) \ 514 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 515 { \ 516 unsigned long irq_flags; \ 517 int rc; \ 518 spin_lock_irqsave(shost->host_lock, irq_flags); \ 519 scsi_cmd_get_serial(shost, cmd); \ 520 rc = func_name##_lck (cmd, cmd->scsi_done); \ 521 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 522 return rc; \ 523 } 524 525 526/* 527 * shost state: If you alter this, you also need to alter scsi_sysfs.c 528 * (for the ascii descriptions) and the state model enforcer: 529 * scsi_host_set_state() 530 */ 531enum scsi_host_state { 532 SHOST_CREATED = 1, 533 SHOST_RUNNING, 534 SHOST_CANCEL, 535 SHOST_DEL, 536 SHOST_RECOVERY, 537 SHOST_CANCEL_RECOVERY, 538 SHOST_DEL_RECOVERY, 539}; 540 541struct Scsi_Host { 542 /* 543 * __devices is protected by the host_lock, but you should 544 * usually use scsi_device_lookup / shost_for_each_device 545 * to access it and don't care about locking yourself. 546 * In the rare case of being in irq context you can use 547 * their __ prefixed variants with the lock held. NEVER 548 * access this list directly from a driver. 549 */ 550 struct list_head __devices; 551 struct list_head __targets; 552 553 struct list_head starved_list; 554 555 spinlock_t default_lock; 556 spinlock_t *host_lock; 557 558 struct mutex scan_mutex;/* serialize scanning activity */ 559 560 struct list_head eh_cmd_q; 561 struct task_struct * ehandler; /* Error recovery thread. */ 562 struct completion * eh_action; /* Wait for specific actions on the 563 host. */ 564 wait_queue_head_t host_wait; 565 struct scsi_host_template *hostt; 566 struct scsi_transport_template *transportt; 567 568 /* 569 * Area to keep a shared tag map (if needed, will be 570 * NULL if not). 571 */ 572 union { 573 struct blk_queue_tag *bqt; 574 struct blk_mq_tag_set tag_set; 575 }; 576 577 atomic_t host_busy; /* commands actually active on low-level */ 578 atomic_t host_blocked; 579 580 unsigned int host_failed; /* commands that failed. 581 protected by host_lock */ 582 unsigned int host_eh_scheduled; /* EH scheduled without command */ 583 584 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 585 586 /* next two fields are used to bound the time spent in error handling */ 587 int eh_deadline; 588 unsigned long last_reset; 589 590 591 /* 592 * These three parameters can be used to allow for wide scsi, 593 * and for host adapters that support multiple busses 594 * The last two should be set to 1 more than the actual max id 595 * or lun (e.g. 8 for SCSI parallel systems). 596 */ 597 unsigned int max_channel; 598 unsigned int max_id; 599 u64 max_lun; 600 601 /* 602 * This is a unique identifier that must be assigned so that we 603 * have some way of identifying each detected host adapter properly 604 * and uniquely. For hosts that do not support more than one card 605 * in the system at one time, this does not need to be set. It is 606 * initialized to 0 in scsi_register. 607 */ 608 unsigned int unique_id; 609 610 /* 611 * The maximum length of SCSI commands that this host can accept. 612 * Probably 12 for most host adapters, but could be 16 for others. 613 * or 260 if the driver supports variable length cdbs. 614 * For drivers that don't set this field, a value of 12 is 615 * assumed. 616 */ 617 unsigned short max_cmd_len; 618 619 int this_id; 620 int can_queue; 621 short cmd_per_lun; 622 short unsigned int sg_tablesize; 623 short unsigned int sg_prot_tablesize; 624 unsigned int max_sectors; 625 unsigned long dma_boundary; 626 /* 627 * In scsi-mq mode, the number of hardware queues supported by the LLD. 628 * 629 * Note: it is assumed that each hardware queue has a queue depth of 630 * can_queue. In other words, the total queue depth per host 631 * is nr_hw_queues * can_queue. 632 */ 633 unsigned nr_hw_queues; 634 /* 635 * Used to assign serial numbers to the cmds. 636 * Protected by the host lock. 637 */ 638 unsigned long cmd_serial_number; 639 640 unsigned active_mode:2; 641 unsigned unchecked_isa_dma:1; 642 unsigned use_clustering:1; 643 644 /* 645 * Host has requested that no further requests come through for the 646 * time being. 647 */ 648 unsigned host_self_blocked:1; 649 650 /* 651 * Host uses correct SCSI ordering not PC ordering. The bit is 652 * set for the minority of drivers whose authors actually read 653 * the spec ;). 654 */ 655 unsigned reverse_ordering:1; 656 657 /* Task mgmt function in progress */ 658 unsigned tmf_in_progress:1; 659 660 /* Asynchronous scan in progress */ 661 unsigned async_scan:1; 662 663 /* Don't resume host in EH */ 664 unsigned eh_noresume:1; 665 666 /* The controller does not support WRITE SAME */ 667 unsigned no_write_same:1; 668 669 unsigned use_blk_mq:1; 670 unsigned use_cmd_list:1; 671 672 /* Host responded with short (<36 bytes) INQUIRY result */ 673 unsigned short_inquiry:1; 674 675 /* 676 * Optional work queue to be utilized by the transport 677 */ 678 char work_q_name[20]; 679 struct workqueue_struct *work_q; 680 681 /* 682 * Task management function work queue 683 */ 684 struct workqueue_struct *tmf_work_q; 685 686 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 687 unsigned no_scsi2_lun_in_cdb:1; 688 689 /* 690 * Value host_blocked counts down from 691 */ 692 unsigned int max_host_blocked; 693 694 /* Protection Information */ 695 unsigned int prot_capabilities; 696 unsigned char prot_guard_type; 697 698 /* legacy crap */ 699 unsigned long base; 700 unsigned long io_port; 701 unsigned char n_io_port; 702 unsigned char dma_channel; 703 unsigned int irq; 704 705 706 enum scsi_host_state shost_state; 707 708 /* ldm bits */ 709 struct device shost_gendev, shost_dev; 710 711 /* 712 * List of hosts per template. 713 * 714 * This is only for use by scsi_module.c for legacy templates. 715 * For these access to it is synchronized implicitly by 716 * module_init/module_exit. 717 */ 718 struct list_head sht_legacy_list; 719 720 /* 721 * Points to the transport data (if any) which is allocated 722 * separately 723 */ 724 void *shost_data; 725 726 /* 727 * Points to the physical bus device we'd use to do DMA 728 * Needed just in case we have virtual hosts. 729 */ 730 struct device *dma_dev; 731 732 /* 733 * We should ensure that this is aligned, both for better performance 734 * and also because some compilers (m68k) don't automatically force 735 * alignment to a long boundary. 736 */ 737 unsigned long hostdata[0] /* Used for storage of host specific stuff */ 738 __attribute__ ((aligned (sizeof(unsigned long)))); 739}; 740 741#define class_to_shost(d) \ 742 container_of(d, struct Scsi_Host, shost_dev) 743 744#define shost_printk(prefix, shost, fmt, a...) \ 745 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 746 747static inline void *shost_priv(struct Scsi_Host *shost) 748{ 749 return (void *)shost->hostdata; 750} 751 752int scsi_is_host_device(const struct device *); 753 754static inline struct Scsi_Host *dev_to_shost(struct device *dev) 755{ 756 while (!scsi_is_host_device(dev)) { 757 if (!dev->parent) 758 return NULL; 759 dev = dev->parent; 760 } 761 return container_of(dev, struct Scsi_Host, shost_gendev); 762} 763 764static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 765{ 766 return shost->shost_state == SHOST_RECOVERY || 767 shost->shost_state == SHOST_CANCEL_RECOVERY || 768 shost->shost_state == SHOST_DEL_RECOVERY || 769 shost->tmf_in_progress; 770} 771 772static inline bool shost_use_blk_mq(struct Scsi_Host *shost) 773{ 774 return shost->use_blk_mq; 775} 776 777extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 778extern void scsi_flush_work(struct Scsi_Host *); 779 780extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); 781extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 782 struct device *, 783 struct device *); 784extern void scsi_scan_host(struct Scsi_Host *); 785extern void scsi_rescan_device(struct device *); 786extern void scsi_remove_host(struct Scsi_Host *); 787extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 788extern void scsi_host_put(struct Scsi_Host *t); 789extern struct Scsi_Host *scsi_host_lookup(unsigned short); 790extern const char *scsi_host_state_name(enum scsi_host_state); 791extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *); 792 793static inline int __must_check scsi_add_host(struct Scsi_Host *host, 794 struct device *dev) 795{ 796 return scsi_add_host_with_dma(host, dev, dev); 797} 798 799static inline struct device *scsi_get_device(struct Scsi_Host *shost) 800{ 801 return shost->shost_gendev.parent; 802} 803 804/** 805 * scsi_host_scan_allowed - Is scanning of this host allowed 806 * @shost: Pointer to Scsi_Host. 807 **/ 808static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 809{ 810 return shost->shost_state == SHOST_RUNNING || 811 shost->shost_state == SHOST_RECOVERY; 812} 813 814extern void scsi_unblock_requests(struct Scsi_Host *); 815extern void scsi_block_requests(struct Scsi_Host *); 816 817struct class_container; 818 819/* 820 * These two functions are used to allocate and free a pseudo device 821 * which will connect to the host adapter itself rather than any 822 * physical device. You must deallocate when you are done with the 823 * thing. This physical pseudo-device isn't real and won't be available 824 * from any high-level drivers. 825 */ 826extern void scsi_free_host_dev(struct scsi_device *); 827extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); 828 829/* 830 * DIF defines the exchange of protection information between 831 * initiator and SBC block device. 832 * 833 * DIX defines the exchange of protection information between OS and 834 * initiator. 835 */ 836enum scsi_host_prot_capabilities { 837 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 838 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 839 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 840 841 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 842 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 843 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 844 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 845}; 846 847/* 848 * SCSI hosts which support the Data Integrity Extensions must 849 * indicate their capabilities by setting the prot_capabilities using 850 * this call. 851 */ 852static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 853{ 854 shost->prot_capabilities = mask; 855} 856 857static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 858{ 859 return shost->prot_capabilities; 860} 861 862static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 863{ 864 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 865} 866 867static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 868{ 869 static unsigned char cap[] = { 0, 870 SHOST_DIF_TYPE1_PROTECTION, 871 SHOST_DIF_TYPE2_PROTECTION, 872 SHOST_DIF_TYPE3_PROTECTION }; 873 874 if (target_type >= ARRAY_SIZE(cap)) 875 return 0; 876 877 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 878} 879 880static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 881{ 882#if defined(CONFIG_BLK_DEV_INTEGRITY) 883 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 884 SHOST_DIX_TYPE1_PROTECTION, 885 SHOST_DIX_TYPE2_PROTECTION, 886 SHOST_DIX_TYPE3_PROTECTION }; 887 888 if (target_type >= ARRAY_SIZE(cap)) 889 return 0; 890 891 return shost->prot_capabilities & cap[target_type]; 892#endif 893 return 0; 894} 895 896/* 897 * All DIX-capable initiators must support the T10-mandated CRC 898 * checksum. Controllers can optionally implement the IP checksum 899 * scheme which has much lower impact on system performance. Note 900 * that the main rationale for the checksum is to match integrity 901 * metadata with data. Detecting bit errors are a job for ECC memory 902 * and buses. 903 */ 904 905enum scsi_host_guard_type { 906 SHOST_DIX_GUARD_CRC = 1 << 0, 907 SHOST_DIX_GUARD_IP = 1 << 1, 908}; 909 910static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 911{ 912 shost->prot_guard_type = type; 913} 914 915static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 916{ 917 return shost->prot_guard_type; 918} 919 920/* legacy interfaces */ 921extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int); 922extern void scsi_unregister(struct Scsi_Host *); 923extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 924 925#endif /* _SCSI_SCSI_HOST_H */ 926