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