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 14 struct request_queue; 15 struct block_device; 16 struct completion; 17 struct module; 18 struct scsi_cmnd; 19 struct scsi_device; 20 struct scsi_host_cmd_pool; 21 struct scsi_target; 22 struct Scsi_Host; 23 struct scsi_host_cmd_pool; 24 struct scsi_transport_template; 25 struct 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 50 struct 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 For new-style drivers 56 * just perform all work in your module initialization function. 57 * 58 * Status: OBSOLETE 59 */ 60 int (* detect)(struct scsi_host_template *); 61 62 /* 63 * Used as unload callback for hosts with old-style drivers. 64 * 65 * Status: OBSOLETE 66 */ 67 int (* release)(struct Scsi_Host *); 68 69 /* 70 * The info function will return whatever useful information the 71 * developer sees fit.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 /* 456 * Countdown for host blocking with no commands outstanding. 457 */ 458 unsigned int max_host_blocked; 459 460 /* 461 * Default value for the blocking. If the queue is empty, 462 * host_blocked counts down in the request_fn until it restarts 463 * host operations as zero is reached. 464 * 465 * FIXME: This should probably be a value in the template 466 */ 467 #define SCSI_DEFAULT_HOST_BLOCKED 7 468 469 /* 470 * Pointer to the sysfs class properties for this host, NULL terminated. 471 */ 472 struct device_attribute **shost_attrs; 473 474 /* 475 * Pointer to the SCSI device properties for this host, NULL terminated. 476 */ 477 struct device_attribute **sdev_attrs; 478 479 /* 480 * List of hosts per template. 481 * 482 * This is only for use by scsi_module.c for legacy templates. 483 * For these access to it is synchronized implicitly by 484 * module_init/module_exit. 485 */ 486 struct list_head legacy_hosts; 487 488 /* 489 * Vendor Identifier associated with the host 490 * 491 * Note: When specifying vendor_id, be sure to read the 492 * Vendor Type and ID formatting requirements specified in 493 * scsi_netlink.h 494 */ 495 u64 vendor_id; 496 497 /* 498 * Additional per-command data allocated for the driver. 499 */ 500 unsigned int cmd_size; 501 struct scsi_host_cmd_pool *cmd_pool; 502 }; 503 504 /* 505 * Temporary #define for host lock push down. Can be removed when all 506 * drivers have been updated to take advantage of unlocked 507 * queuecommand. 508 * 509 */ 510 #define DEF_SCSI_QCMD(func_name) \ 511 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 512 { \ 513 unsigned long irq_flags; \ 514 int rc; \ 515 spin_lock_irqsave(shost->host_lock, irq_flags); \ 516 scsi_cmd_get_serial(shost, cmd); \ 517 rc = func_name##_lck (cmd, cmd->scsi_done); \ 518 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 519 return rc; \ 520 } 521 522 523 /* 524 * shost state: If you alter this, you also need to alter scsi_sysfs.c 525 * (for the ascii descriptions) and the state model enforcer: 526 * scsi_host_set_state() 527 */ 528 enum scsi_host_state { 529 SHOST_CREATED = 1, 530 SHOST_RUNNING, 531 SHOST_CANCEL, 532 SHOST_DEL, 533 SHOST_RECOVERY, 534 SHOST_CANCEL_RECOVERY, 535 SHOST_DEL_RECOVERY, 536 }; 537 538 struct Scsi_Host { 539 /* 540 * __devices is protected by the host_lock, but you should 541 * usually use scsi_device_lookup / shost_for_each_device 542 * to access it and don't care about locking yourself. 543 * In the rare case of being in irq context you can use 544 * their __ prefixed variants with the lock held. NEVER 545 * access this list directly from a driver. 546 */ 547 struct list_head __devices; 548 struct list_head __targets; 549 550 struct list_head starved_list; 551 552 spinlock_t default_lock; 553 spinlock_t *host_lock; 554 555 struct mutex scan_mutex;/* serialize scanning activity */ 556 557 struct list_head eh_cmd_q; 558 struct task_struct * ehandler; /* Error recovery thread. */ 559 struct completion * eh_action; /* Wait for specific actions on the 560 host. */ 561 wait_queue_head_t host_wait; 562 struct scsi_host_template *hostt; 563 struct scsi_transport_template *transportt; 564 565 /* 566 * Area to keep a shared tag map (if needed, will be 567 * NULL if not). 568 */ 569 union { 570 struct blk_queue_tag *bqt; 571 struct blk_mq_tag_set tag_set; 572 }; 573 574 struct rcu_head rcu; 575 576 atomic_t host_busy; /* commands actually active on low-level */ 577 atomic_t host_blocked; 578 579 unsigned int host_failed; /* commands that failed. 580 protected by host_lock */ 581 unsigned int host_eh_scheduled; /* EH scheduled without command */ 582 583 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 584 585 /* next two fields are used to bound the time spent in error handling */ 586 int eh_deadline; 587 unsigned long last_reset; 588 589 590 /* 591 * These three parameters can be used to allow for wide scsi, 592 * and for host adapters that support multiple busses 593 * The last two should be set to 1 more than the actual max id 594 * or lun (e.g. 8 for SCSI parallel systems). 595 */ 596 unsigned int max_channel; 597 unsigned int max_id; 598 u64 max_lun; 599 600 /* 601 * This is a unique identifier that must be assigned so that we 602 * have some way of identifying each detected host adapter properly 603 * and uniquely. For hosts that do not support more than one card 604 * in the system at one time, this does not need to be set. It is 605 * initialized to 0 in scsi_register. 606 */ 607 unsigned int unique_id; 608 609 /* 610 * The maximum length of SCSI commands that this host can accept. 611 * Probably 12 for most host adapters, but could be 16 for others. 612 * or 260 if the driver supports variable length cdbs. 613 * For drivers that don't set this field, a value of 12 is 614 * assumed. 615 */ 616 unsigned short max_cmd_len; 617 618 int this_id; 619 int can_queue; 620 short cmd_per_lun; 621 short unsigned int sg_tablesize; 622 short unsigned int sg_prot_tablesize; 623 unsigned int max_sectors; 624 unsigned long dma_boundary; 625 /* 626 * In scsi-mq mode, the number of hardware queues supported by the LLD. 627 * 628 * Note: it is assumed that each hardware queue has a queue depth of 629 * can_queue. In other words, the total queue depth per host 630 * is nr_hw_queues * can_queue. 631 */ 632 unsigned nr_hw_queues; 633 /* 634 * Used to assign serial numbers to the cmds. 635 * Protected by the host lock. 636 */ 637 unsigned long cmd_serial_number; 638 639 unsigned active_mode:2; 640 unsigned unchecked_isa_dma:1; 641 unsigned use_clustering:1; 642 643 /* 644 * Host has requested that no further requests come through for the 645 * time being. 646 */ 647 unsigned host_self_blocked:1; 648 649 /* 650 * Host uses correct SCSI ordering not PC ordering. The bit is 651 * set for the minority of drivers whose authors actually read 652 * the spec ;). 653 */ 654 unsigned reverse_ordering:1; 655 656 /* Task mgmt function in progress */ 657 unsigned tmf_in_progress:1; 658 659 /* Asynchronous scan in progress */ 660 unsigned async_scan:1; 661 662 /* Don't resume host in EH */ 663 unsigned eh_noresume:1; 664 665 /* The controller does not support WRITE SAME */ 666 unsigned no_write_same:1; 667 668 unsigned use_blk_mq:1; 669 unsigned use_cmd_list:1; 670 671 /* Host responded with short (<36 bytes) INQUIRY result */ 672 unsigned short_inquiry:1; 673 674 /* 675 * Optional work queue to be utilized by the transport 676 */ 677 char work_q_name[20]; 678 struct workqueue_struct *work_q; 679 680 /* 681 * Task management function work queue 682 */ 683 struct workqueue_struct *tmf_work_q; 684 685 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 686 unsigned no_scsi2_lun_in_cdb:1; 687 688 /* 689 * Value host_blocked counts down from 690 */ 691 unsigned int max_host_blocked; 692 693 /* Protection Information */ 694 unsigned int prot_capabilities; 695 unsigned char prot_guard_type; 696 697 /* legacy crap */ 698 unsigned long base; 699 unsigned long io_port; 700 unsigned char n_io_port; 701 unsigned char dma_channel; 702 unsigned int irq; 703 704 705 enum scsi_host_state shost_state; 706 707 /* ldm bits */ 708 struct device shost_gendev, shost_dev; 709 710 /* 711 * List of hosts per template. 712 * 713 * This is only for use by scsi_module.c for legacy templates. 714 * For these access to it is synchronized implicitly by 715 * module_init/module_exit. 716 */ 717 struct list_head sht_legacy_list; 718 719 /* 720 * Points to the transport data (if any) which is allocated 721 * separately 722 */ 723 void *shost_data; 724 725 /* 726 * Points to the physical bus device we'd use to do DMA 727 * Needed just in case we have virtual hosts. 728 */ 729 struct device *dma_dev; 730 731 /* 732 * We should ensure that this is aligned, both for better performance 733 * and also because some compilers (m68k) don't automatically force 734 * alignment to a long boundary. 735 */ 736 unsigned long hostdata[0] /* Used for storage of host specific stuff */ 737 __attribute__ ((aligned (sizeof(unsigned long)))); 738 }; 739 740 #define class_to_shost(d) \ 741 container_of(d, struct Scsi_Host, shost_dev) 742 743 #define shost_printk(prefix, shost, fmt, a...) \ 744 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 745 746 static inline void *shost_priv(struct Scsi_Host *shost) 747 { 748 return (void *)shost->hostdata; 749 } 750 751 int scsi_is_host_device(const struct device *); 752 753 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 754 { 755 while (!scsi_is_host_device(dev)) { 756 if (!dev->parent) 757 return NULL; 758 dev = dev->parent; 759 } 760 return container_of(dev, struct Scsi_Host, shost_gendev); 761 } 762 763 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 764 { 765 return shost->shost_state == SHOST_RECOVERY || 766 shost->shost_state == SHOST_CANCEL_RECOVERY || 767 shost->shost_state == SHOST_DEL_RECOVERY || 768 shost->tmf_in_progress; 769 } 770 771 static inline bool shost_use_blk_mq(struct Scsi_Host *shost) 772 { 773 return shost->use_blk_mq; 774 } 775 776 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 777 extern void scsi_flush_work(struct Scsi_Host *); 778 779 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); 780 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 781 struct device *, 782 struct device *); 783 extern void scsi_scan_host(struct Scsi_Host *); 784 extern void scsi_rescan_device(struct device *); 785 extern void scsi_remove_host(struct Scsi_Host *); 786 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 787 extern void scsi_host_put(struct Scsi_Host *t); 788 extern struct Scsi_Host *scsi_host_lookup(unsigned short); 789 extern const char *scsi_host_state_name(enum scsi_host_state); 790 extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *); 791 792 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 793 struct device *dev) 794 { 795 return scsi_add_host_with_dma(host, dev, dev); 796 } 797 798 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 799 { 800 return shost->shost_gendev.parent; 801 } 802 803 /** 804 * scsi_host_scan_allowed - Is scanning of this host allowed 805 * @shost: Pointer to Scsi_Host. 806 **/ 807 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 808 { 809 return shost->shost_state == SHOST_RUNNING || 810 shost->shost_state == SHOST_RECOVERY; 811 } 812 813 extern void scsi_unblock_requests(struct Scsi_Host *); 814 extern void scsi_block_requests(struct Scsi_Host *); 815 816 struct class_container; 817 818 /* 819 * These two functions are used to allocate and free a pseudo device 820 * which will connect to the host adapter itself rather than any 821 * physical device. You must deallocate when you are done with the 822 * thing. This physical pseudo-device isn't real and won't be available 823 * from any high-level drivers. 824 */ 825 extern void scsi_free_host_dev(struct scsi_device *); 826 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); 827 828 /* 829 * DIF defines the exchange of protection information between 830 * initiator and SBC block device. 831 * 832 * DIX defines the exchange of protection information between OS and 833 * initiator. 834 */ 835 enum scsi_host_prot_capabilities { 836 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 837 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 838 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 839 840 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 841 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 842 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 843 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 844 }; 845 846 /* 847 * SCSI hosts which support the Data Integrity Extensions must 848 * indicate their capabilities by setting the prot_capabilities using 849 * this call. 850 */ 851 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 852 { 853 shost->prot_capabilities = mask; 854 } 855 856 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 857 { 858 return shost->prot_capabilities; 859 } 860 861 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 862 { 863 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 864 } 865 866 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 867 { 868 static unsigned char cap[] = { 0, 869 SHOST_DIF_TYPE1_PROTECTION, 870 SHOST_DIF_TYPE2_PROTECTION, 871 SHOST_DIF_TYPE3_PROTECTION }; 872 873 if (target_type >= ARRAY_SIZE(cap)) 874 return 0; 875 876 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 877 } 878 879 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 880 { 881 #if defined(CONFIG_BLK_DEV_INTEGRITY) 882 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 883 SHOST_DIX_TYPE1_PROTECTION, 884 SHOST_DIX_TYPE2_PROTECTION, 885 SHOST_DIX_TYPE3_PROTECTION }; 886 887 if (target_type >= ARRAY_SIZE(cap)) 888 return 0; 889 890 return shost->prot_capabilities & cap[target_type]; 891 #endif 892 return 0; 893 } 894 895 /* 896 * All DIX-capable initiators must support the T10-mandated CRC 897 * checksum. Controllers can optionally implement the IP checksum 898 * scheme which has much lower impact on system performance. Note 899 * that the main rationale for the checksum is to match integrity 900 * metadata with data. Detecting bit errors are a job for ECC memory 901 * and buses. 902 */ 903 904 enum scsi_host_guard_type { 905 SHOST_DIX_GUARD_CRC = 1 << 0, 906 SHOST_DIX_GUARD_IP = 1 << 1, 907 }; 908 909 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 910 { 911 shost->prot_guard_type = type; 912 } 913 914 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 915 { 916 return shost->prot_guard_type; 917 } 918 919 /* legacy interfaces */ 920 extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int); 921 extern void scsi_unregister(struct Scsi_Host *); 922 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 923 924 #endif /* _SCSI_SCSI_HOST_H */ 925