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 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 25 26 #define SG_ALL SG_CHUNK_SIZE 27 28 #define MODE_UNKNOWN 0x00 29 #define MODE_INITIATOR 0x01 30 #define MODE_TARGET 0x02 31 32 struct scsi_host_template { 33 /* 34 * Put fields referenced in IO submission path together in 35 * same cacheline 36 */ 37 38 /* 39 * Additional per-command data allocated for the driver. 40 */ 41 unsigned int cmd_size; 42 43 /* 44 * The queuecommand function is used to queue up a scsi 45 * command block to the LLDD. When the driver finished 46 * processing the command the done callback is invoked. 47 * 48 * If queuecommand returns 0, then the driver has accepted the 49 * command. It must also push it to the HBA if the scsi_cmnd 50 * flag SCMD_LAST is set, or if the driver does not implement 51 * commit_rqs. The done() function must be called on the command 52 * when the driver has finished with it. (you may call done on the 53 * command before queuecommand returns, but in this case you 54 * *must* return 0 from queuecommand). 55 * 56 * Queuecommand may also reject the command, in which case it may 57 * not touch the command and must not call done() for it. 58 * 59 * There are two possible rejection returns: 60 * 61 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 62 * allow commands to other devices serviced by this host. 63 * 64 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 65 * host temporarily. 66 * 67 * For compatibility, any other non-zero return is treated the 68 * same as SCSI_MLQUEUE_HOST_BUSY. 69 * 70 * NOTE: "temporarily" means either until the next command for# 71 * this device/host completes, or a period of time determined by 72 * I/O pressure in the system if there are no other outstanding 73 * commands. 74 * 75 * STATUS: REQUIRED 76 */ 77 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); 78 79 /* 80 * The commit_rqs function is used to trigger a hardware 81 * doorbell after some requests have been queued with 82 * queuecommand, when an error is encountered before sending 83 * the request with SCMD_LAST set. 84 * 85 * STATUS: OPTIONAL 86 */ 87 void (*commit_rqs)(struct Scsi_Host *, u16); 88 89 struct module *module; 90 const char *name; 91 92 /* 93 * The info function will return whatever useful information the 94 * developer sees fit. If not provided, then the name field will 95 * be used instead. 96 * 97 * Status: OPTIONAL 98 */ 99 const char *(*info)(struct Scsi_Host *); 100 101 /* 102 * Ioctl interface 103 * 104 * Status: OPTIONAL 105 */ 106 int (*ioctl)(struct scsi_device *dev, unsigned int cmd, 107 void __user *arg); 108 109 110 #ifdef CONFIG_COMPAT 111 /* 112 * Compat handler. Handle 32bit ABI. 113 * When unknown ioctl is passed return -ENOIOCTLCMD. 114 * 115 * Status: OPTIONAL 116 */ 117 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, 118 void __user *arg); 119 #endif 120 121 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 122 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 123 124 /* 125 * This is an error handling strategy routine. You don't need to 126 * define one of these if you don't want to - there is a default 127 * routine that is present that should work in most cases. For those 128 * driver authors that have the inclination and ability to write their 129 * own strategy routine, this is where it is specified. Note - the 130 * strategy routine is *ALWAYS* run in the context of the kernel eh 131 * thread. Thus you are guaranteed to *NOT* be in an interrupt 132 * handler when you execute this, and you are also guaranteed to 133 * *NOT* have any other commands being queued while you are in the 134 * strategy routine. When you return from this function, operations 135 * return to normal. 136 * 137 * See scsi_error.c scsi_unjam_host for additional comments about 138 * what this function should and should not be attempting to do. 139 * 140 * Status: REQUIRED (at least one of them) 141 */ 142 int (* eh_abort_handler)(struct scsi_cmnd *); 143 int (* eh_device_reset_handler)(struct scsi_cmnd *); 144 int (* eh_target_reset_handler)(struct scsi_cmnd *); 145 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 146 int (* eh_host_reset_handler)(struct scsi_cmnd *); 147 148 /* 149 * Before the mid layer attempts to scan for a new device where none 150 * currently exists, it will call this entry in your driver. Should 151 * your driver need to allocate any structs or perform any other init 152 * items in order to send commands to a currently unused target/lun 153 * combo, then this is where you can perform those allocations. This 154 * is specifically so that drivers won't have to perform any kind of 155 * "is this a new device" checks in their queuecommand routine, 156 * thereby making the hot path a bit quicker. 157 * 158 * Return values: 0 on success, non-0 on failure 159 * 160 * Deallocation: If we didn't find any devices at this ID, you will 161 * get an immediate call to slave_destroy(). If we find something 162 * here then you will get a call to slave_configure(), then the 163 * device will be used for however long it is kept around, then when 164 * the device is removed from the system (or * possibly at reboot 165 * time), you will then get a call to slave_destroy(). This is 166 * assuming you implement slave_configure and slave_destroy. 167 * However, if you allocate memory and hang it off the device struct, 168 * then you must implement the slave_destroy() routine at a minimum 169 * in order to avoid leaking memory 170 * each time a device is tore down. 171 * 172 * Status: OPTIONAL 173 */ 174 int (* slave_alloc)(struct scsi_device *); 175 176 /* 177 * Once the device has responded to an INQUIRY and we know the 178 * device is online, we call into the low level driver with the 179 * struct scsi_device *. If the low level device driver implements 180 * this function, it *must* perform the task of setting the queue 181 * depth on the device. All other tasks are optional and depend 182 * on what the driver supports and various implementation details. 183 * 184 * Things currently recommended to be handled at this time include: 185 * 186 * 1. Setting the device queue depth. Proper setting of this is 187 * described in the comments for scsi_change_queue_depth. 188 * 2. Determining if the device supports the various synchronous 189 * negotiation protocols. The device struct will already have 190 * responded to INQUIRY and the results of the standard items 191 * will have been shoved into the various device flag bits, eg. 192 * device->sdtr will be true if the device supports SDTR messages. 193 * 3. Allocating command structs that the device will need. 194 * 4. Setting the default timeout on this device (if needed). 195 * 5. Anything else the low level driver might want to do on a device 196 * specific setup basis... 197 * 6. Return 0 on success, non-0 on error. The device will be marked 198 * as offline on error so that no access will occur. If you return 199 * non-0, your slave_destroy routine will never get called for this 200 * device, so don't leave any loose memory hanging around, clean 201 * up after yourself before returning non-0 202 * 203 * Status: OPTIONAL 204 */ 205 int (* slave_configure)(struct scsi_device *); 206 207 /* 208 * Immediately prior to deallocating the device and after all activity 209 * has ceased the mid layer calls this point so that the low level 210 * driver may completely detach itself from the scsi device and vice 211 * versa. The low level driver is responsible for freeing any memory 212 * it allocated in the slave_alloc or slave_configure calls. 213 * 214 * Status: OPTIONAL 215 */ 216 void (* slave_destroy)(struct scsi_device *); 217 218 /* 219 * Before the mid layer attempts to scan for a new device attached 220 * to a target where no target currently exists, it will call this 221 * entry in your driver. Should your driver need to allocate any 222 * structs or perform any other init items in order to send commands 223 * to a currently unused target, then this is where you can perform 224 * those allocations. 225 * 226 * Return values: 0 on success, non-0 on failure 227 * 228 * Status: OPTIONAL 229 */ 230 int (* target_alloc)(struct scsi_target *); 231 232 /* 233 * Immediately prior to deallocating the target structure, and 234 * after all activity to attached scsi devices has ceased, the 235 * midlayer calls this point so that the driver may deallocate 236 * and terminate any references to the target. 237 * 238 * Status: OPTIONAL 239 */ 240 void (* target_destroy)(struct scsi_target *); 241 242 /* 243 * If a host has the ability to discover targets on its own instead 244 * of scanning the entire bus, it can fill in this function and 245 * call scsi_scan_host(). This function will be called periodically 246 * until it returns 1 with the scsi_host and the elapsed time of 247 * the scan in jiffies. 248 * 249 * Status: OPTIONAL 250 */ 251 int (* scan_finished)(struct Scsi_Host *, unsigned long); 252 253 /* 254 * If the host wants to be called before the scan starts, but 255 * after the midlayer has set up ready for the scan, it can fill 256 * in this function. 257 * 258 * Status: OPTIONAL 259 */ 260 void (* scan_start)(struct Scsi_Host *); 261 262 /* 263 * Fill in this function to allow the queue depth of this host 264 * to be changeable (on a per device basis). Returns either 265 * the current queue depth setting (may be different from what 266 * was passed in) or an error. An error should only be 267 * returned if the requested depth is legal but the driver was 268 * unable to set it. If the requested depth is illegal, the 269 * driver should set and return the closest legal queue depth. 270 * 271 * Status: OPTIONAL 272 */ 273 int (* change_queue_depth)(struct scsi_device *, int); 274 275 /* 276 * This functions lets the driver expose the queue mapping 277 * to the block layer. 278 * 279 * Status: OPTIONAL 280 */ 281 int (* map_queues)(struct Scsi_Host *shost); 282 283 /* 284 * Check if scatterlists need to be padded for DMA draining. 285 * 286 * Status: OPTIONAL 287 */ 288 bool (* dma_need_drain)(struct request *rq); 289 290 /* 291 * This function determines the BIOS parameters for a given 292 * harddisk. These tend to be numbers that are made up by 293 * the host adapter. Parameters: 294 * size, device, list (heads, sectors, cylinders) 295 * 296 * Status: OPTIONAL 297 */ 298 int (* bios_param)(struct scsi_device *, struct block_device *, 299 sector_t, int []); 300 301 /* 302 * This function is called when one or more partitions on the 303 * device reach beyond the end of the device. 304 * 305 * Status: OPTIONAL 306 */ 307 void (*unlock_native_capacity)(struct scsi_device *); 308 309 /* 310 * Can be used to export driver statistics and other infos to the 311 * world outside the kernel ie. userspace and it also provides an 312 * interface to feed the driver with information. 313 * 314 * Status: OBSOLETE 315 */ 316 int (*show_info)(struct seq_file *, struct Scsi_Host *); 317 int (*write_info)(struct Scsi_Host *, char *, int); 318 319 /* 320 * This is an optional routine that allows the transport to become 321 * involved when a scsi io timer fires. The return value tells the 322 * timer routine how to finish the io timeout handling. 323 * 324 * Status: OPTIONAL 325 */ 326 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 327 /* 328 * Optional routine that allows the transport to decide if a cmd 329 * is retryable. Return true if the transport is in a state the 330 * cmd should be retried on. 331 */ 332 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 333 334 /* This is an optional routine that allows transport to initiate 335 * LLD adapter or firmware reset using sysfs attribute. 336 * 337 * Return values: 0 on success, -ve value on failure. 338 * 339 * Status: OPTIONAL 340 */ 341 342 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 343 #define SCSI_ADAPTER_RESET 1 344 #define SCSI_FIRMWARE_RESET 2 345 346 347 /* 348 * Name of proc directory 349 */ 350 const char *proc_name; 351 352 /* 353 * Used to store the procfs directory if a driver implements the 354 * show_info method. 355 */ 356 struct proc_dir_entry *proc_dir; 357 358 /* 359 * This determines if we will use a non-interrupt driven 360 * or an interrupt driven scheme. It is set to the maximum number 361 * of simultaneous commands a single hw queue in HBA will accept. 362 */ 363 int can_queue; 364 365 /* 366 * In many instances, especially where disconnect / reconnect are 367 * supported, our host also has an ID on the SCSI bus. If this is 368 * the case, then it must be reserved. Please set this_id to -1 if 369 * your setup is in single initiator mode, and the host lacks an 370 * ID. 371 */ 372 int this_id; 373 374 /* 375 * This determines the degree to which the host adapter is capable 376 * of scatter-gather. 377 */ 378 unsigned short sg_tablesize; 379 unsigned short sg_prot_tablesize; 380 381 /* 382 * Set this if the host adapter has limitations beside segment count. 383 */ 384 unsigned int max_sectors; 385 386 /* 387 * Maximum size in bytes of a single segment. 388 */ 389 unsigned int max_segment_size; 390 391 /* 392 * DMA scatter gather segment boundary limit. A segment crossing this 393 * boundary will be split in two. 394 */ 395 unsigned long dma_boundary; 396 397 unsigned long virt_boundary_mask; 398 399 /* 400 * This specifies "machine infinity" for host templates which don't 401 * limit the transfer size. Note this limit represents an absolute 402 * maximum, and may be over the transfer limits allowed for 403 * individual devices (e.g. 256 for SCSI-1). 404 */ 405 #define SCSI_DEFAULT_MAX_SECTORS 1024 406 407 /* 408 * True if this host adapter can make good use of linked commands. 409 * This will allow more than one command to be queued to a given 410 * unit on a given host. Set this to the maximum number of command 411 * blocks to be provided for each device. Set this to 1 for one 412 * command block per lun, 2 for two, etc. Do not set this to 0. 413 * You should make sure that the host adapter will do the right thing 414 * before you try setting this above 1. 415 */ 416 short cmd_per_lun; 417 418 /* 419 * present contains counter indicating how many boards of this 420 * type were found when we did the scan. 421 */ 422 unsigned char present; 423 424 /* If use block layer to manage tags, this is tag allocation policy */ 425 int tag_alloc_policy; 426 427 /* 428 * Track QUEUE_FULL events and reduce queue depth on demand. 429 */ 430 unsigned track_queue_depth:1; 431 432 /* 433 * This specifies the mode that a LLD supports. 434 */ 435 unsigned supported_mode:2; 436 437 /* 438 * True if this host adapter uses unchecked DMA onto an ISA bus. 439 */ 440 unsigned unchecked_isa_dma: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 host uses host-wide tagspace */ 456 unsigned host_tagset: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 * Pointer to the SCSI device attribute groups for this host, 484 * NULL terminated. 485 */ 486 const struct attribute_group **sdev_groups; 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 struct scsi_host_cmd_pool *cmd_pool; 498 499 /* Delay for runtime autosuspend */ 500 int rpm_autosuspend_delay; 501 }; 502 503 /* 504 * Temporary #define for host lock push down. Can be removed when all 505 * drivers have been updated to take advantage of unlocked 506 * queuecommand. 507 * 508 */ 509 #define DEF_SCSI_QCMD(func_name) \ 510 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 511 { \ 512 unsigned long irq_flags; \ 513 int rc; \ 514 spin_lock_irqsave(shost->host_lock, irq_flags); \ 515 rc = func_name##_lck (cmd, cmd->scsi_done); \ 516 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 517 return rc; \ 518 } 519 520 521 /* 522 * shost state: If you alter this, you also need to alter scsi_sysfs.c 523 * (for the ascii descriptions) and the state model enforcer: 524 * scsi_host_set_state() 525 */ 526 enum scsi_host_state { 527 SHOST_CREATED = 1, 528 SHOST_RUNNING, 529 SHOST_CANCEL, 530 SHOST_DEL, 531 SHOST_RECOVERY, 532 SHOST_CANCEL_RECOVERY, 533 SHOST_DEL_RECOVERY, 534 }; 535 536 struct Scsi_Host { 537 /* 538 * __devices is protected by the host_lock, but you should 539 * usually use scsi_device_lookup / shost_for_each_device 540 * to access it and don't care about locking yourself. 541 * In the rare case of being in irq context you can use 542 * their __ prefixed variants with the lock held. NEVER 543 * access this list directly from a driver. 544 */ 545 struct list_head __devices; 546 struct list_head __targets; 547 548 struct list_head starved_list; 549 550 spinlock_t default_lock; 551 spinlock_t *host_lock; 552 553 struct mutex scan_mutex;/* serialize scanning activity */ 554 555 struct list_head eh_cmd_q; 556 struct task_struct * ehandler; /* Error recovery thread. */ 557 struct completion * eh_action; /* Wait for specific actions on the 558 host. */ 559 wait_queue_head_t host_wait; 560 struct scsi_host_template *hostt; 561 struct scsi_transport_template *transportt; 562 563 /* Area to keep a shared tag map */ 564 struct blk_mq_tag_set tag_set; 565 566 atomic_t host_blocked; 567 568 unsigned int host_failed; /* commands that failed. 569 protected by host_lock */ 570 unsigned int host_eh_scheduled; /* EH scheduled without command */ 571 572 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 573 574 /* next two fields are used to bound the time spent in error handling */ 575 int eh_deadline; 576 unsigned long last_reset; 577 578 579 /* 580 * These three parameters can be used to allow for wide scsi, 581 * and for host adapters that support multiple busses 582 * The last two should be set to 1 more than the actual max id 583 * or lun (e.g. 8 for SCSI parallel systems). 584 */ 585 unsigned int max_channel; 586 unsigned int max_id; 587 u64 max_lun; 588 589 /* 590 * This is a unique identifier that must be assigned so that we 591 * have some way of identifying each detected host adapter properly 592 * and uniquely. For hosts that do not support more than one card 593 * in the system at one time, this does not need to be set. It is 594 * initialized to 0 in scsi_register. 595 */ 596 unsigned int unique_id; 597 598 /* 599 * The maximum length of SCSI commands that this host can accept. 600 * Probably 12 for most host adapters, but could be 16 for others. 601 * or 260 if the driver supports variable length cdbs. 602 * For drivers that don't set this field, a value of 12 is 603 * assumed. 604 */ 605 unsigned short max_cmd_len; 606 607 int this_id; 608 int can_queue; 609 short cmd_per_lun; 610 short unsigned int sg_tablesize; 611 short unsigned int sg_prot_tablesize; 612 unsigned int max_sectors; 613 unsigned int max_segment_size; 614 unsigned long dma_boundary; 615 unsigned long virt_boundary_mask; 616 /* 617 * In scsi-mq mode, the number of hardware queues supported by the LLD. 618 * 619 * Note: it is assumed that each hardware queue has a queue depth of 620 * can_queue. In other words, the total queue depth per host 621 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 622 * the total queue depth is can_queue. 623 */ 624 unsigned nr_hw_queues; 625 unsigned active_mode:2; 626 unsigned unchecked_isa_dma:1; 627 628 /* 629 * Host has requested that no further requests come through for the 630 * time being. 631 */ 632 unsigned host_self_blocked:1; 633 634 /* 635 * Host uses correct SCSI ordering not PC ordering. The bit is 636 * set for the minority of drivers whose authors actually read 637 * the spec ;). 638 */ 639 unsigned reverse_ordering:1; 640 641 /* Task mgmt function in progress */ 642 unsigned tmf_in_progress:1; 643 644 /* Asynchronous scan in progress */ 645 unsigned async_scan:1; 646 647 /* Don't resume host in EH */ 648 unsigned eh_noresume:1; 649 650 /* The controller does not support WRITE SAME */ 651 unsigned no_write_same:1; 652 653 /* True if the host uses host-wide tagspace */ 654 unsigned host_tagset:1; 655 656 /* Host responded with short (<36 bytes) INQUIRY result */ 657 unsigned short_inquiry:1; 658 659 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 660 unsigned no_scsi2_lun_in_cdb:1; 661 662 /* 663 * Optional work queue to be utilized by the transport 664 */ 665 char work_q_name[20]; 666 struct workqueue_struct *work_q; 667 668 /* 669 * Task management function work queue 670 */ 671 struct workqueue_struct *tmf_work_q; 672 673 /* 674 * Value host_blocked counts down from 675 */ 676 unsigned int max_host_blocked; 677 678 /* Protection Information */ 679 unsigned int prot_capabilities; 680 unsigned char prot_guard_type; 681 682 /* legacy crap */ 683 unsigned long base; 684 unsigned long io_port; 685 unsigned char n_io_port; 686 unsigned char dma_channel; 687 unsigned int irq; 688 689 690 enum scsi_host_state shost_state; 691 692 /* ldm bits */ 693 struct device shost_gendev, shost_dev; 694 695 /* 696 * Points to the transport data (if any) which is allocated 697 * separately 698 */ 699 void *shost_data; 700 701 /* 702 * Points to the physical bus device we'd use to do DMA 703 * Needed just in case we have virtual hosts. 704 */ 705 struct device *dma_dev; 706 707 /* 708 * We should ensure that this is aligned, both for better performance 709 * and also because some compilers (m68k) don't automatically force 710 * alignment to a long boundary. 711 */ 712 unsigned long hostdata[] /* Used for storage of host specific stuff */ 713 __attribute__ ((aligned (sizeof(unsigned long)))); 714 }; 715 716 #define class_to_shost(d) \ 717 container_of(d, struct Scsi_Host, shost_dev) 718 719 #define shost_printk(prefix, shost, fmt, a...) \ 720 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 721 722 static inline void *shost_priv(struct Scsi_Host *shost) 723 { 724 return (void *)shost->hostdata; 725 } 726 727 int scsi_is_host_device(const struct device *); 728 729 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 730 { 731 while (!scsi_is_host_device(dev)) { 732 if (!dev->parent) 733 return NULL; 734 dev = dev->parent; 735 } 736 return container_of(dev, struct Scsi_Host, shost_gendev); 737 } 738 739 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 740 { 741 return shost->shost_state == SHOST_RECOVERY || 742 shost->shost_state == SHOST_CANCEL_RECOVERY || 743 shost->shost_state == SHOST_DEL_RECOVERY || 744 shost->tmf_in_progress; 745 } 746 747 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 748 extern void scsi_flush_work(struct Scsi_Host *); 749 750 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); 751 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 752 struct device *, 753 struct device *); 754 extern void scsi_scan_host(struct Scsi_Host *); 755 extern void scsi_rescan_device(struct device *); 756 extern void scsi_remove_host(struct Scsi_Host *); 757 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 758 extern int scsi_host_busy(struct Scsi_Host *shost); 759 extern void scsi_host_put(struct Scsi_Host *t); 760 extern struct Scsi_Host *scsi_host_lookup(unsigned short); 761 extern const char *scsi_host_state_name(enum scsi_host_state); 762 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 763 int status); 764 765 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 766 struct device *dev) 767 { 768 return scsi_add_host_with_dma(host, dev, dev); 769 } 770 771 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 772 { 773 return shost->shost_gendev.parent; 774 } 775 776 /** 777 * scsi_host_scan_allowed - Is scanning of this host allowed 778 * @shost: Pointer to Scsi_Host. 779 **/ 780 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 781 { 782 return shost->shost_state == SHOST_RUNNING || 783 shost->shost_state == SHOST_RECOVERY; 784 } 785 786 extern void scsi_unblock_requests(struct Scsi_Host *); 787 extern void scsi_block_requests(struct Scsi_Host *); 788 extern int scsi_host_block(struct Scsi_Host *shost); 789 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 790 791 void scsi_host_busy_iter(struct Scsi_Host *, 792 bool (*fn)(struct scsi_cmnd *, void *, bool), void *priv); 793 794 struct class_container; 795 796 /* 797 * These two functions are used to allocate and free a pseudo device 798 * which will connect to the host adapter itself rather than any 799 * physical device. You must deallocate when you are done with the 800 * thing. This physical pseudo-device isn't real and won't be available 801 * from any high-level drivers. 802 */ 803 extern void scsi_free_host_dev(struct scsi_device *); 804 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); 805 806 /* 807 * DIF defines the exchange of protection information between 808 * initiator and SBC block device. 809 * 810 * DIX defines the exchange of protection information between OS and 811 * initiator. 812 */ 813 enum scsi_host_prot_capabilities { 814 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 815 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 816 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 817 818 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 819 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 820 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 821 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 822 }; 823 824 /* 825 * SCSI hosts which support the Data Integrity Extensions must 826 * indicate their capabilities by setting the prot_capabilities using 827 * this call. 828 */ 829 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 830 { 831 shost->prot_capabilities = mask; 832 } 833 834 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 835 { 836 return shost->prot_capabilities; 837 } 838 839 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 840 { 841 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 842 } 843 844 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 845 { 846 static unsigned char cap[] = { 0, 847 SHOST_DIF_TYPE1_PROTECTION, 848 SHOST_DIF_TYPE2_PROTECTION, 849 SHOST_DIF_TYPE3_PROTECTION }; 850 851 if (target_type >= ARRAY_SIZE(cap)) 852 return 0; 853 854 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 855 } 856 857 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 858 { 859 #if defined(CONFIG_BLK_DEV_INTEGRITY) 860 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 861 SHOST_DIX_TYPE1_PROTECTION, 862 SHOST_DIX_TYPE2_PROTECTION, 863 SHOST_DIX_TYPE3_PROTECTION }; 864 865 if (target_type >= ARRAY_SIZE(cap)) 866 return 0; 867 868 return shost->prot_capabilities & cap[target_type]; 869 #endif 870 return 0; 871 } 872 873 /* 874 * All DIX-capable initiators must support the T10-mandated CRC 875 * checksum. Controllers can optionally implement the IP checksum 876 * scheme which has much lower impact on system performance. Note 877 * that the main rationale for the checksum is to match integrity 878 * metadata with data. Detecting bit errors are a job for ECC memory 879 * and buses. 880 */ 881 882 enum scsi_host_guard_type { 883 SHOST_DIX_GUARD_CRC = 1 << 0, 884 SHOST_DIX_GUARD_IP = 1 << 1, 885 }; 886 887 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 888 { 889 shost->prot_guard_type = type; 890 } 891 892 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 893 { 894 return shost->prot_guard_type; 895 } 896 897 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 898 899 #endif /* _SCSI_SCSI_HOST_H */ 900