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 <linux/seq_file.h> 10 #include <linux/blk-mq.h> 11 #include <scsi/scsi.h> 12 13 struct request_queue; 14 struct block_device; 15 struct completion; 16 struct module; 17 struct scsi_cmnd; 18 struct scsi_device; 19 struct scsi_host_cmd_pool; 20 struct scsi_target; 21 struct Scsi_Host; 22 struct scsi_host_cmd_pool; 23 struct scsi_transport_template; 24 struct blk_queue_tags; 25 26 27 /* 28 * The various choices mean: 29 * NONE: Self evident. Host adapter is not capable of scatter-gather. 30 * ALL: Means that the host adapter module can do scatter-gather, 31 * and that there is no limit to the size of the table to which 32 * we scatter/gather data. The value we set here is the maximum 33 * single element sglist. To use chained sglists, the adapter 34 * has to set a value beyond ALL (and correctly use the chain 35 * handling API. 36 * Anything else: Indicates the maximum number of chains that can be 37 * used in one scatter-gather request. 38 */ 39 #define SG_NONE 0 40 #define SG_ALL SCSI_MAX_SG_SEGMENTS 41 42 #define MODE_UNKNOWN 0x00 43 #define MODE_INITIATOR 0x01 44 #define MODE_TARGET 0x02 45 46 #define DISABLE_CLUSTERING 0 47 #define ENABLE_CLUSTERING 1 48 49 struct scsi_host_template { 50 struct module *module; 51 const char *name; 52 53 /* 54 * Used to initialize old-style drivers. For new-style drivers 55 * just perform all work in your module initialization function. 56 * 57 * Status: OBSOLETE 58 */ 59 int (* detect)(struct scsi_host_template *); 60 61 /* 62 * Used as unload callback for hosts with old-style drivers. 63 * 64 * Status: OBSOLETE 65 */ 66 int (* release)(struct Scsi_Host *); 67 68 /* 69 * The info function will return whatever useful information the 70 * developer sees fit. If not provided, then the name field will 71 * be used instead. 72 * 73 * Status: OPTIONAL 74 */ 75 const char *(* info)(struct Scsi_Host *); 76 77 /* 78 * Ioctl interface 79 * 80 * Status: OPTIONAL 81 */ 82 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg); 83 84 85 #ifdef CONFIG_COMPAT 86 /* 87 * Compat handler. Handle 32bit ABI. 88 * When unknown ioctl is passed return -ENOIOCTLCMD. 89 * 90 * Status: OPTIONAL 91 */ 92 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg); 93 #endif 94 95 /* 96 * The queuecommand function is used to queue up a scsi 97 * command block to the LLDD. When the driver finished 98 * processing the command the done callback is invoked. 99 * 100 * If queuecommand returns 0, then the HBA has accepted the 101 * command. The done() function must be called on the command 102 * when the driver has finished with it. (you may call done on the 103 * command before queuecommand returns, but in this case you 104 * *must* return 0 from queuecommand). 105 * 106 * Queuecommand may also reject the command, in which case it may 107 * not touch the command and must not call done() for it. 108 * 109 * There are two possible rejection returns: 110 * 111 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 112 * allow commands to other devices serviced by this host. 113 * 114 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 115 * host temporarily. 116 * 117 * For compatibility, any other non-zero return is treated the 118 * same as SCSI_MLQUEUE_HOST_BUSY. 119 * 120 * NOTE: "temporarily" means either until the next command for# 121 * this device/host completes, or a period of time determined by 122 * I/O pressure in the system if there are no other outstanding 123 * commands. 124 * 125 * STATUS: REQUIRED 126 */ 127 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); 128 129 /* 130 * This is an error handling strategy routine. You don't need to 131 * define one of these if you don't want to - there is a default 132 * routine that is present that should work in most cases. For those 133 * driver authors that have the inclination and ability to write their 134 * own strategy routine, this is where it is specified. Note - the 135 * strategy routine is *ALWAYS* run in the context of the kernel eh 136 * thread. Thus you are guaranteed to *NOT* be in an interrupt 137 * handler when you execute this, and you are also guaranteed to 138 * *NOT* have any other commands being queued while you are in the 139 * strategy routine. When you return from this function, operations 140 * return to normal. 141 * 142 * See scsi_error.c scsi_unjam_host for additional comments about 143 * what this function should and should not be attempting to do. 144 * 145 * Status: REQUIRED (at least one of them) 146 */ 147 int (* eh_abort_handler)(struct scsi_cmnd *); 148 int (* eh_device_reset_handler)(struct scsi_cmnd *); 149 int (* eh_target_reset_handler)(struct scsi_cmnd *); 150 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 151 int (* eh_host_reset_handler)(struct scsi_cmnd *); 152 153 /* 154 * Before the mid layer attempts to scan for a new device where none 155 * currently exists, it will call this entry in your driver. Should 156 * your driver need to allocate any structs or perform any other init 157 * items in order to send commands to a currently unused target/lun 158 * combo, then this is where you can perform those allocations. This 159 * is specifically so that drivers won't have to perform any kind of 160 * "is this a new device" checks in their queuecommand routine, 161 * thereby making the hot path a bit quicker. 162 * 163 * Return values: 0 on success, non-0 on failure 164 * 165 * Deallocation: If we didn't find any devices at this ID, you will 166 * get an immediate call to slave_destroy(). If we find something 167 * here then you will get a call to slave_configure(), then the 168 * device will be used for however long it is kept around, then when 169 * the device is removed from the system (or * possibly at reboot 170 * time), you will then get a call to slave_destroy(). This is 171 * assuming you implement slave_configure and slave_destroy. 172 * However, if you allocate memory and hang it off the device struct, 173 * then you must implement the slave_destroy() routine at a minimum 174 * in order to avoid leaking memory 175 * each time a device is tore down. 176 * 177 * Status: OPTIONAL 178 */ 179 int (* slave_alloc)(struct scsi_device *); 180 181 /* 182 * Once the device has responded to an INQUIRY and we know the 183 * device is online, we call into the low level driver with the 184 * struct scsi_device *. If the low level device driver implements 185 * this function, it *must* perform the task of setting the queue 186 * depth on the device. All other tasks are optional and depend 187 * on what the driver supports and various implementation details. 188 * 189 * Things currently recommended to be handled at this time include: 190 * 191 * 1. Setting the device queue depth. Proper setting of this is 192 * described in the comments for scsi_change_queue_depth. 193 * 2. Determining if the device supports the various synchronous 194 * negotiation protocols. The device struct will already have 195 * responded to INQUIRY and the results of the standard items 196 * will have been shoved into the various device flag bits, eg. 197 * device->sdtr will be true if the device supports SDTR messages. 198 * 3. Allocating command structs that the device will need. 199 * 4. Setting the default timeout on this device (if needed). 200 * 5. Anything else the low level driver might want to do on a device 201 * specific setup basis... 202 * 6. Return 0 on success, non-0 on error. The device will be marked 203 * as offline on error so that no access will occur. If you return 204 * non-0, your slave_destroy routine will never get called for this 205 * device, so don't leave any loose memory hanging around, clean 206 * up after yourself before returning non-0 207 * 208 * Status: OPTIONAL 209 */ 210 int (* slave_configure)(struct scsi_device *); 211 212 /* 213 * Immediately prior to deallocating the device and after all activity 214 * has ceased the mid layer calls this point so that the low level 215 * driver may completely detach itself from the scsi device and vice 216 * versa. The low level driver is responsible for freeing any memory 217 * it allocated in the slave_alloc or slave_configure calls. 218 * 219 * Status: OPTIONAL 220 */ 221 void (* slave_destroy)(struct scsi_device *); 222 223 /* 224 * Before the mid layer attempts to scan for a new device attached 225 * to a target where no target currently exists, it will call this 226 * entry in your driver. Should your driver need to allocate any 227 * structs or perform any other init items in order to send commands 228 * to a currently unused target, then this is where you can perform 229 * those allocations. 230 * 231 * Return values: 0 on success, non-0 on failure 232 * 233 * Status: OPTIONAL 234 */ 235 int (* target_alloc)(struct scsi_target *); 236 237 /* 238 * Immediately prior to deallocating the target structure, and 239 * after all activity to attached scsi devices has ceased, the 240 * midlayer calls this point so that the driver may deallocate 241 * and terminate any references to the target. 242 * 243 * Status: OPTIONAL 244 */ 245 void (* target_destroy)(struct scsi_target *); 246 247 /* 248 * If a host has the ability to discover targets on its own instead 249 * of scanning the entire bus, it can fill in this function and 250 * call scsi_scan_host(). This function will be called periodically 251 * until it returns 1 with the scsi_host and the elapsed time of 252 * the scan in jiffies. 253 * 254 * Status: OPTIONAL 255 */ 256 int (* scan_finished)(struct Scsi_Host *, unsigned long); 257 258 /* 259 * If the host wants to be called before the scan starts, but 260 * after the midlayer has set up ready for the scan, it can fill 261 * in this function. 262 * 263 * Status: OPTIONAL 264 */ 265 void (* scan_start)(struct Scsi_Host *); 266 267 /* 268 * Fill in this function to allow the queue depth of this host 269 * to be changeable (on a per device basis). Returns either 270 * the current queue depth setting (may be different from what 271 * was passed in) or an error. An error should only be 272 * returned if the requested depth is legal but the driver was 273 * unable to set it. If the requested depth is illegal, the 274 * driver should set and return the closest legal queue depth. 275 * 276 * Status: OPTIONAL 277 */ 278 int (* change_queue_depth)(struct scsi_device *, int); 279 280 /* 281 * This function determines the BIOS parameters for a given 282 * harddisk. These tend to be numbers that are made up by 283 * the host adapter. Parameters: 284 * size, device, list (heads, sectors, cylinders) 285 * 286 * Status: OPTIONAL 287 */ 288 int (* bios_param)(struct scsi_device *, struct block_device *, 289 sector_t, int []); 290 291 /* 292 * This function is called when one or more partitions on the 293 * device reach beyond the end of the device. 294 * 295 * Status: OPTIONAL 296 */ 297 void (*unlock_native_capacity)(struct scsi_device *); 298 299 /* 300 * Can be used to export driver statistics and other infos to the 301 * world outside the kernel ie. userspace and it also provides an 302 * interface to feed the driver with information. 303 * 304 * Status: OBSOLETE 305 */ 306 int (*show_info)(struct seq_file *, struct Scsi_Host *); 307 int (*write_info)(struct Scsi_Host *, char *, int); 308 309 /* 310 * This is an optional routine that allows the transport to become 311 * involved when a scsi io timer fires. The return value tells the 312 * timer routine how to finish the io timeout handling: 313 * EH_HANDLED: I fixed the error, please complete the command 314 * EH_RESET_TIMER: I need more time, reset the timer and 315 * begin counting again 316 * EH_NOT_HANDLED Begin normal error recovery 317 * 318 * Status: OPTIONAL 319 */ 320 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 321 322 /* This is an optional routine that allows transport to initiate 323 * LLD adapter or firmware reset using sysfs attribute. 324 * 325 * Return values: 0 on success, -ve value on failure. 326 * 327 * Status: OPTIONAL 328 */ 329 330 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 331 #define SCSI_ADAPTER_RESET 1 332 #define SCSI_FIRMWARE_RESET 2 333 334 335 /* 336 * Name of proc directory 337 */ 338 const char *proc_name; 339 340 /* 341 * Used to store the procfs directory if a driver implements the 342 * show_info method. 343 */ 344 struct proc_dir_entry *proc_dir; 345 346 /* 347 * This determines if we will use a non-interrupt driven 348 * or an interrupt driven scheme. It is set to the maximum number 349 * of simultaneous commands a given host adapter will accept. 350 */ 351 int can_queue; 352 353 /* 354 * In many instances, especially where disconnect / reconnect are 355 * supported, our host also has an ID on the SCSI bus. If this is 356 * the case, then it must be reserved. Please set this_id to -1 if 357 * your setup is in single initiator mode, and the host lacks an 358 * ID. 359 */ 360 int this_id; 361 362 /* 363 * This determines the degree to which the host adapter is capable 364 * of scatter-gather. 365 */ 366 unsigned short sg_tablesize; 367 unsigned short sg_prot_tablesize; 368 369 /* 370 * Set this if the host adapter has limitations beside segment count. 371 */ 372 unsigned int max_sectors; 373 374 /* 375 * DMA scatter gather segment boundary limit. A segment crossing this 376 * boundary will be split in two. 377 */ 378 unsigned long dma_boundary; 379 380 /* 381 * This specifies "machine infinity" for host templates which don't 382 * limit the transfer size. Note this limit represents an absolute 383 * maximum, and may be over the transfer limits allowed for 384 * individual devices (e.g. 256 for SCSI-1). 385 */ 386 #define SCSI_DEFAULT_MAX_SECTORS 1024 387 388 /* 389 * True if this host adapter can make good use of linked commands. 390 * This will allow more than one command to be queued to a given 391 * unit on a given host. Set this to the maximum number of command 392 * blocks to be provided for each device. Set this to 1 for one 393 * command block per lun, 2 for two, etc. Do not set this to 0. 394 * You should make sure that the host adapter will do the right thing 395 * before you try setting this above 1. 396 */ 397 short cmd_per_lun; 398 399 /* 400 * present contains counter indicating how many boards of this 401 * type were found when we did the scan. 402 */ 403 unsigned char present; 404 405 /* If use block layer to manage tags, this is tag allocation policy */ 406 int tag_alloc_policy; 407 408 /* 409 * Let the block layer assigns tags to all commands. 410 */ 411 unsigned use_blk_tags:1; 412 413 /* 414 * Track QUEUE_FULL events and reduce queue depth on demand. 415 */ 416 unsigned track_queue_depth:1; 417 418 /* 419 * This specifies the mode that a LLD supports. 420 */ 421 unsigned supported_mode:2; 422 423 /* 424 * True if this host adapter uses unchecked DMA onto an ISA bus. 425 */ 426 unsigned unchecked_isa_dma:1; 427 428 /* 429 * True if this host adapter can make good use of clustering. 430 * I originally thought that if the tablesize was large that it 431 * was a waste of CPU cycles to prepare a cluster list, but 432 * it works out that the Buslogic is faster if you use a smaller 433 * number of segments (i.e. use clustering). I guess it is 434 * inefficient. 435 */ 436 unsigned use_clustering:1; 437 438 /* 439 * True for emulated SCSI host adapters (e.g. ATAPI). 440 */ 441 unsigned emulated:1; 442 443 /* 444 * True if the low-level driver performs its own reset-settle delays. 445 */ 446 unsigned skip_settle_delay:1; 447 448 /* True if the controller does not support WRITE SAME */ 449 unsigned no_write_same:1; 450 451 /* 452 * True if asynchronous aborts are not supported 453 */ 454 unsigned no_async_abort:1; 455 456 /* 457 * Countdown for host blocking with no commands outstanding. 458 */ 459 unsigned int max_host_blocked; 460 461 /* 462 * Default value for the blocking. If the queue is empty, 463 * host_blocked counts down in the request_fn until it restarts 464 * host operations as zero is reached. 465 * 466 * FIXME: This should probably be a value in the template 467 */ 468 #define SCSI_DEFAULT_HOST_BLOCKED 7 469 470 /* 471 * Pointer to the sysfs class properties for this host, NULL terminated. 472 */ 473 struct device_attribute **shost_attrs; 474 475 /* 476 * Pointer to the SCSI device properties for this host, NULL terminated. 477 */ 478 struct device_attribute **sdev_attrs; 479 480 /* 481 * List of hosts per template. 482 * 483 * This is only for use by scsi_module.c for legacy templates. 484 * For these access to it is synchronized implicitly by 485 * module_init/module_exit. 486 */ 487 struct list_head legacy_hosts; 488 489 /* 490 * Vendor Identifier associated with the host 491 * 492 * Note: When specifying vendor_id, be sure to read the 493 * Vendor Type and ID formatting requirements specified in 494 * scsi_netlink.h 495 */ 496 u64 vendor_id; 497 498 /* 499 * Additional per-command data allocated for the driver. 500 */ 501 unsigned int cmd_size; 502 struct scsi_host_cmd_pool *cmd_pool; 503 504 /* temporary flag to disable blk-mq I/O path */ 505 bool disable_blk_mq; 506 }; 507 508 /* 509 * Temporary #define for host lock push down. Can be removed when all 510 * drivers have been updated to take advantage of unlocked 511 * queuecommand. 512 * 513 */ 514 #define DEF_SCSI_QCMD(func_name) \ 515 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 516 { \ 517 unsigned long irq_flags; \ 518 int rc; \ 519 spin_lock_irqsave(shost->host_lock, irq_flags); \ 520 scsi_cmd_get_serial(shost, cmd); \ 521 rc = func_name##_lck (cmd, cmd->scsi_done); \ 522 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 523 return rc; \ 524 } 525 526 527 /* 528 * shost state: If you alter this, you also need to alter scsi_sysfs.c 529 * (for the ascii descriptions) and the state model enforcer: 530 * scsi_host_set_state() 531 */ 532 enum scsi_host_state { 533 SHOST_CREATED = 1, 534 SHOST_RUNNING, 535 SHOST_CANCEL, 536 SHOST_DEL, 537 SHOST_RECOVERY, 538 SHOST_CANCEL_RECOVERY, 539 SHOST_DEL_RECOVERY, 540 }; 541 542 struct Scsi_Host { 543 /* 544 * __devices is protected by the host_lock, but you should 545 * usually use scsi_device_lookup / shost_for_each_device 546 * to access it and don't care about locking yourself. 547 * In the rare case of being in irq context you can use 548 * their __ prefixed variants with the lock held. NEVER 549 * access this list directly from a driver. 550 */ 551 struct list_head __devices; 552 struct list_head __targets; 553 554 struct scsi_host_cmd_pool *cmd_pool; 555 spinlock_t free_list_lock; 556 struct list_head free_list; /* backup store of cmd structs */ 557 struct list_head starved_list; 558 559 spinlock_t default_lock; 560 spinlock_t *host_lock; 561 562 struct mutex scan_mutex;/* serialize scanning activity */ 563 564 struct list_head eh_cmd_q; 565 struct task_struct * ehandler; /* Error recovery thread. */ 566 struct completion * eh_action; /* Wait for specific actions on the 567 host. */ 568 wait_queue_head_t host_wait; 569 struct scsi_host_template *hostt; 570 struct scsi_transport_template *transportt; 571 572 /* 573 * Area to keep a shared tag map (if needed, will be 574 * NULL if not). 575 */ 576 union { 577 struct blk_queue_tag *bqt; 578 struct blk_mq_tag_set tag_set; 579 }; 580 581 atomic_t host_busy; /* commands actually active on low-level */ 582 atomic_t host_blocked; 583 584 unsigned int host_failed; /* commands that failed. 585 protected by host_lock */ 586 unsigned int host_eh_scheduled; /* EH scheduled without command */ 587 588 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 589 590 /* next two fields are used to bound the time spent in error handling */ 591 int eh_deadline; 592 unsigned long last_reset; 593 594 595 /* 596 * These three parameters can be used to allow for wide scsi, 597 * and for host adapters that support multiple busses 598 * The last two should be set to 1 more than the actual max id 599 * or lun (e.g. 8 for SCSI parallel systems). 600 */ 601 unsigned int max_channel; 602 unsigned int max_id; 603 u64 max_lun; 604 605 /* 606 * This is a unique identifier that must be assigned so that we 607 * have some way of identifying each detected host adapter properly 608 * and uniquely. For hosts that do not support more than one card 609 * in the system at one time, this does not need to be set. It is 610 * initialized to 0 in scsi_register. 611 */ 612 unsigned int unique_id; 613 614 /* 615 * The maximum length of SCSI commands that this host can accept. 616 * Probably 12 for most host adapters, but could be 16 for others. 617 * or 260 if the driver supports variable length cdbs. 618 * For drivers that don't set this field, a value of 12 is 619 * assumed. 620 */ 621 unsigned short max_cmd_len; 622 623 int this_id; 624 int can_queue; 625 short cmd_per_lun; 626 short unsigned int sg_tablesize; 627 short unsigned int sg_prot_tablesize; 628 unsigned int max_sectors; 629 unsigned long dma_boundary; 630 /* 631 * In scsi-mq mode, the number of hardware queues supported by the LLD. 632 * 633 * Note: it is assumed that each hardware queue has a queue depth of 634 * can_queue. In other words, the total queue depth per host 635 * is nr_hw_queues * can_queue. 636 */ 637 unsigned nr_hw_queues; 638 /* 639 * Used to assign serial numbers to the cmds. 640 * Protected by the host lock. 641 */ 642 unsigned long cmd_serial_number; 643 644 unsigned active_mode:2; 645 unsigned unchecked_isa_dma:1; 646 unsigned use_clustering:1; 647 648 /* 649 * Host has requested that no further requests come through for the 650 * time being. 651 */ 652 unsigned host_self_blocked:1; 653 654 /* 655 * Host uses correct SCSI ordering not PC ordering. The bit is 656 * set for the minority of drivers whose authors actually read 657 * the spec ;). 658 */ 659 unsigned reverse_ordering:1; 660 661 /* Task mgmt function in progress */ 662 unsigned tmf_in_progress:1; 663 664 /* Asynchronous scan in progress */ 665 unsigned async_scan:1; 666 667 /* Don't resume host in EH */ 668 unsigned eh_noresume:1; 669 670 /* The controller does not support WRITE SAME */ 671 unsigned no_write_same:1; 672 673 unsigned use_blk_mq:1; 674 unsigned use_cmd_list:1; 675 676 /* 677 * Optional work queue to be utilized by the transport 678 */ 679 char work_q_name[20]; 680 struct workqueue_struct *work_q; 681 682 /* 683 * Task management function work queue 684 */ 685 struct workqueue_struct *tmf_work_q; 686 687 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 688 unsigned no_scsi2_lun_in_cdb:1; 689 690 /* 691 * Value host_blocked counts down from 692 */ 693 unsigned int max_host_blocked; 694 695 /* Protection Information */ 696 unsigned int prot_capabilities; 697 unsigned char prot_guard_type; 698 699 /* 700 * q used for scsi_tgt msgs, async events or any other requests that 701 * need to be processed in userspace 702 */ 703 struct request_queue *uspace_req_q; 704 705 /* legacy crap */ 706 unsigned long base; 707 unsigned long io_port; 708 unsigned char n_io_port; 709 unsigned char dma_channel; 710 unsigned int irq; 711 712 713 enum scsi_host_state shost_state; 714 715 /* ldm bits */ 716 struct device shost_gendev, shost_dev; 717 718 /* 719 * List of hosts per template. 720 * 721 * This is only for use by scsi_module.c for legacy templates. 722 * For these access to it is synchronized implicitly by 723 * module_init/module_exit. 724 */ 725 struct list_head sht_legacy_list; 726 727 /* 728 * Points to the transport data (if any) which is allocated 729 * separately 730 */ 731 void *shost_data; 732 733 /* 734 * Points to the physical bus device we'd use to do DMA 735 * Needed just in case we have virtual hosts. 736 */ 737 struct device *dma_dev; 738 739 /* 740 * We should ensure that this is aligned, both for better performance 741 * and also because some compilers (m68k) don't automatically force 742 * alignment to a long boundary. 743 */ 744 unsigned long hostdata[0] /* Used for storage of host specific stuff */ 745 __attribute__ ((aligned (sizeof(unsigned long)))); 746 }; 747 748 #define class_to_shost(d) \ 749 container_of(d, struct Scsi_Host, shost_dev) 750 751 #define shost_printk(prefix, shost, fmt, a...) \ 752 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 753 754 static inline void *shost_priv(struct Scsi_Host *shost) 755 { 756 return (void *)shost->hostdata; 757 } 758 759 int scsi_is_host_device(const struct device *); 760 761 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 762 { 763 while (!scsi_is_host_device(dev)) { 764 if (!dev->parent) 765 return NULL; 766 dev = dev->parent; 767 } 768 return container_of(dev, struct Scsi_Host, shost_gendev); 769 } 770 771 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 772 { 773 return shost->shost_state == SHOST_RECOVERY || 774 shost->shost_state == SHOST_CANCEL_RECOVERY || 775 shost->shost_state == SHOST_DEL_RECOVERY || 776 shost->tmf_in_progress; 777 } 778 779 extern bool scsi_use_blk_mq; 780 781 static inline bool shost_use_blk_mq(struct Scsi_Host *shost) 782 { 783 return shost->use_blk_mq; 784 } 785 786 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 787 extern void scsi_flush_work(struct Scsi_Host *); 788 789 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); 790 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 791 struct device *, 792 struct device *); 793 extern void scsi_scan_host(struct Scsi_Host *); 794 extern void scsi_rescan_device(struct device *); 795 extern void scsi_remove_host(struct Scsi_Host *); 796 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 797 extern void scsi_host_put(struct Scsi_Host *t); 798 extern struct Scsi_Host *scsi_host_lookup(unsigned short); 799 extern const char *scsi_host_state_name(enum scsi_host_state); 800 extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *); 801 802 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 803 struct device *dev) 804 { 805 return scsi_add_host_with_dma(host, dev, dev); 806 } 807 808 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 809 { 810 return shost->shost_gendev.parent; 811 } 812 813 /** 814 * scsi_host_scan_allowed - Is scanning of this host allowed 815 * @shost: Pointer to Scsi_Host. 816 **/ 817 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 818 { 819 return shost->shost_state == SHOST_RUNNING || 820 shost->shost_state == SHOST_RECOVERY; 821 } 822 823 extern void scsi_unblock_requests(struct Scsi_Host *); 824 extern void scsi_block_requests(struct Scsi_Host *); 825 826 struct class_container; 827 828 extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost, 829 void (*) (struct request_queue *)); 830 /* 831 * These two functions are used to allocate and free a pseudo device 832 * which will connect to the host adapter itself rather than any 833 * physical device. You must deallocate when you are done with the 834 * thing. This physical pseudo-device isn't real and won't be available 835 * from any high-level drivers. 836 */ 837 extern void scsi_free_host_dev(struct scsi_device *); 838 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); 839 840 /* 841 * DIF defines the exchange of protection information between 842 * initiator and SBC block device. 843 * 844 * DIX defines the exchange of protection information between OS and 845 * initiator. 846 */ 847 enum scsi_host_prot_capabilities { 848 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 849 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 850 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 851 852 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 853 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 854 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 855 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 856 }; 857 858 /* 859 * SCSI hosts which support the Data Integrity Extensions must 860 * indicate their capabilities by setting the prot_capabilities using 861 * this call. 862 */ 863 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 864 { 865 shost->prot_capabilities = mask; 866 } 867 868 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 869 { 870 return shost->prot_capabilities; 871 } 872 873 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 874 { 875 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 876 } 877 878 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 879 { 880 static unsigned char cap[] = { 0, 881 SHOST_DIF_TYPE1_PROTECTION, 882 SHOST_DIF_TYPE2_PROTECTION, 883 SHOST_DIF_TYPE3_PROTECTION }; 884 885 if (target_type >= ARRAY_SIZE(cap)) 886 return 0; 887 888 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 889 } 890 891 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 892 { 893 #if defined(CONFIG_BLK_DEV_INTEGRITY) 894 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 895 SHOST_DIX_TYPE1_PROTECTION, 896 SHOST_DIX_TYPE2_PROTECTION, 897 SHOST_DIX_TYPE3_PROTECTION }; 898 899 if (target_type >= ARRAY_SIZE(cap)) 900 return 0; 901 902 return shost->prot_capabilities & cap[target_type]; 903 #endif 904 return 0; 905 } 906 907 /* 908 * All DIX-capable initiators must support the T10-mandated CRC 909 * checksum. Controllers can optionally implement the IP checksum 910 * scheme which has much lower impact on system performance. Note 911 * that the main rationale for the checksum is to match integrity 912 * metadata with data. Detecting bit errors are a job for ECC memory 913 * and buses. 914 */ 915 916 enum scsi_host_guard_type { 917 SHOST_DIX_GUARD_CRC = 1 << 0, 918 SHOST_DIX_GUARD_IP = 1 << 1, 919 }; 920 921 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 922 { 923 shost->prot_guard_type = type; 924 } 925 926 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 927 { 928 return shost->prot_guard_type; 929 } 930 931 /* legacy interfaces */ 932 extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int); 933 extern void scsi_unregister(struct Scsi_Host *); 934 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 935 936 #endif /* _SCSI_SCSI_HOST_H */ 937