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 struct module *module; 34 const char *name; 35 36 /* 37 * The info function will return whatever useful information the 38 * developer sees fit. If not provided, then the name field will 39 * be used instead. 40 * 41 * Status: OPTIONAL 42 */ 43 const char *(* info)(struct Scsi_Host *); 44 45 /* 46 * Ioctl interface 47 * 48 * Status: OPTIONAL 49 */ 50 int (*ioctl)(struct scsi_device *dev, unsigned int cmd, 51 void __user *arg); 52 53 54 #ifdef CONFIG_COMPAT 55 /* 56 * Compat handler. Handle 32bit ABI. 57 * When unknown ioctl is passed return -ENOIOCTLCMD. 58 * 59 * Status: OPTIONAL 60 */ 61 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, 62 void __user *arg); 63 #endif 64 65 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 66 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 67 68 /* 69 * The queuecommand function is used to queue up a scsi 70 * command block to the LLDD. When the driver finished 71 * processing the command the done callback is invoked. 72 * 73 * If queuecommand returns 0, then the driver has accepted the 74 * command. It must also push it to the HBA if the scsi_cmnd 75 * flag SCMD_LAST is set, or if the driver does not implement 76 * commit_rqs. The done() function must be called on the command 77 * when the driver has finished with it. (you may call done on the 78 * command before queuecommand returns, but in this case you 79 * *must* return 0 from queuecommand). 80 * 81 * Queuecommand may also reject the command, in which case it may 82 * not touch the command and must not call done() for it. 83 * 84 * There are two possible rejection returns: 85 * 86 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 87 * allow commands to other devices serviced by this host. 88 * 89 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 90 * host temporarily. 91 * 92 * For compatibility, any other non-zero return is treated the 93 * same as SCSI_MLQUEUE_HOST_BUSY. 94 * 95 * NOTE: "temporarily" means either until the next command for# 96 * this device/host completes, or a period of time determined by 97 * I/O pressure in the system if there are no other outstanding 98 * commands. 99 * 100 * STATUS: REQUIRED 101 */ 102 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); 103 104 /* 105 * The commit_rqs function is used to trigger a hardware 106 * doorbell after some requests have been queued with 107 * queuecommand, when an error is encountered before sending 108 * the request with SCMD_LAST set. 109 * 110 * STATUS: OPTIONAL 111 */ 112 void (*commit_rqs)(struct Scsi_Host *, u16); 113 114 /* 115 * This is an error handling strategy routine. You don't need to 116 * define one of these if you don't want to - there is a default 117 * routine that is present that should work in most cases. For those 118 * driver authors that have the inclination and ability to write their 119 * own strategy routine, this is where it is specified. Note - the 120 * strategy routine is *ALWAYS* run in the context of the kernel eh 121 * thread. Thus you are guaranteed to *NOT* be in an interrupt 122 * handler when you execute this, and you are also guaranteed to 123 * *NOT* have any other commands being queued while you are in the 124 * strategy routine. When you return from this function, operations 125 * return to normal. 126 * 127 * See scsi_error.c scsi_unjam_host for additional comments about 128 * what this function should and should not be attempting to do. 129 * 130 * Status: REQUIRED (at least one of them) 131 */ 132 int (* eh_abort_handler)(struct scsi_cmnd *); 133 int (* eh_device_reset_handler)(struct scsi_cmnd *); 134 int (* eh_target_reset_handler)(struct scsi_cmnd *); 135 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 136 int (* eh_host_reset_handler)(struct scsi_cmnd *); 137 138 /* 139 * Before the mid layer attempts to scan for a new device where none 140 * currently exists, it will call this entry in your driver. Should 141 * your driver need to allocate any structs or perform any other init 142 * items in order to send commands to a currently unused target/lun 143 * combo, then this is where you can perform those allocations. This 144 * is specifically so that drivers won't have to perform any kind of 145 * "is this a new device" checks in their queuecommand routine, 146 * thereby making the hot path a bit quicker. 147 * 148 * Return values: 0 on success, non-0 on failure 149 * 150 * Deallocation: If we didn't find any devices at this ID, you will 151 * get an immediate call to slave_destroy(). If we find something 152 * here then you will get a call to slave_configure(), then the 153 * device will be used for however long it is kept around, then when 154 * the device is removed from the system (or * possibly at reboot 155 * time), you will then get a call to slave_destroy(). This is 156 * assuming you implement slave_configure and slave_destroy. 157 * However, if you allocate memory and hang it off the device struct, 158 * then you must implement the slave_destroy() routine at a minimum 159 * in order to avoid leaking memory 160 * each time a device is tore down. 161 * 162 * Status: OPTIONAL 163 */ 164 int (* slave_alloc)(struct scsi_device *); 165 166 /* 167 * Once the device has responded to an INQUIRY and we know the 168 * device is online, we call into the low level driver with the 169 * struct scsi_device *. If the low level device driver implements 170 * this function, it *must* perform the task of setting the queue 171 * depth on the device. All other tasks are optional and depend 172 * on what the driver supports and various implementation details. 173 * 174 * Things currently recommended to be handled at this time include: 175 * 176 * 1. Setting the device queue depth. Proper setting of this is 177 * described in the comments for scsi_change_queue_depth. 178 * 2. Determining if the device supports the various synchronous 179 * negotiation protocols. The device struct will already have 180 * responded to INQUIRY and the results of the standard items 181 * will have been shoved into the various device flag bits, eg. 182 * device->sdtr will be true if the device supports SDTR messages. 183 * 3. Allocating command structs that the device will need. 184 * 4. Setting the default timeout on this device (if needed). 185 * 5. Anything else the low level driver might want to do on a device 186 * specific setup basis... 187 * 6. Return 0 on success, non-0 on error. The device will be marked 188 * as offline on error so that no access will occur. If you return 189 * non-0, your slave_destroy routine will never get called for this 190 * device, so don't leave any loose memory hanging around, clean 191 * up after yourself before returning non-0 192 * 193 * Status: OPTIONAL 194 */ 195 int (* slave_configure)(struct scsi_device *); 196 197 /* 198 * Immediately prior to deallocating the device and after all activity 199 * has ceased the mid layer calls this point so that the low level 200 * driver may completely detach itself from the scsi device and vice 201 * versa. The low level driver is responsible for freeing any memory 202 * it allocated in the slave_alloc or slave_configure calls. 203 * 204 * Status: OPTIONAL 205 */ 206 void (* slave_destroy)(struct scsi_device *); 207 208 /* 209 * Before the mid layer attempts to scan for a new device attached 210 * to a target where no target currently exists, it will call this 211 * entry in your driver. Should your driver need to allocate any 212 * structs or perform any other init items in order to send commands 213 * to a currently unused target, then this is where you can perform 214 * those allocations. 215 * 216 * Return values: 0 on success, non-0 on failure 217 * 218 * Status: OPTIONAL 219 */ 220 int (* target_alloc)(struct scsi_target *); 221 222 /* 223 * Immediately prior to deallocating the target structure, and 224 * after all activity to attached scsi devices has ceased, the 225 * midlayer calls this point so that the driver may deallocate 226 * and terminate any references to the target. 227 * 228 * Status: OPTIONAL 229 */ 230 void (* target_destroy)(struct scsi_target *); 231 232 /* 233 * If a host has the ability to discover targets on its own instead 234 * of scanning the entire bus, it can fill in this function and 235 * call scsi_scan_host(). This function will be called periodically 236 * until it returns 1 with the scsi_host and the elapsed time of 237 * the scan in jiffies. 238 * 239 * Status: OPTIONAL 240 */ 241 int (* scan_finished)(struct Scsi_Host *, unsigned long); 242 243 /* 244 * If the host wants to be called before the scan starts, but 245 * after the midlayer has set up ready for the scan, it can fill 246 * in this function. 247 * 248 * Status: OPTIONAL 249 */ 250 void (* scan_start)(struct Scsi_Host *); 251 252 /* 253 * Fill in this function to allow the queue depth of this host 254 * to be changeable (on a per device basis). Returns either 255 * the current queue depth setting (may be different from what 256 * was passed in) or an error. An error should only be 257 * returned if the requested depth is legal but the driver was 258 * unable to set it. If the requested depth is illegal, the 259 * driver should set and return the closest legal queue depth. 260 * 261 * Status: OPTIONAL 262 */ 263 int (* change_queue_depth)(struct scsi_device *, int); 264 265 /* 266 * This functions lets the driver expose the queue mapping 267 * to the block layer. 268 * 269 * Status: OPTIONAL 270 */ 271 int (* map_queues)(struct Scsi_Host *shost); 272 273 /* 274 * Check if scatterlists need to be padded for DMA draining. 275 * 276 * Status: OPTIONAL 277 */ 278 bool (* dma_need_drain)(struct request *rq); 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 * 314 * Status: OPTIONAL 315 */ 316 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 317 318 /* This is an optional routine that allows transport to initiate 319 * LLD adapter or firmware reset using sysfs attribute. 320 * 321 * Return values: 0 on success, -ve value on failure. 322 * 323 * Status: OPTIONAL 324 */ 325 326 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 327 #define SCSI_ADAPTER_RESET 1 328 #define SCSI_FIRMWARE_RESET 2 329 330 331 /* 332 * Name of proc directory 333 */ 334 const char *proc_name; 335 336 /* 337 * Used to store the procfs directory if a driver implements the 338 * show_info method. 339 */ 340 struct proc_dir_entry *proc_dir; 341 342 /* 343 * This determines if we will use a non-interrupt driven 344 * or an interrupt driven scheme. It is set to the maximum number 345 * of simultaneous commands a single hw queue in HBA will accept. 346 */ 347 int can_queue; 348 349 /* 350 * In many instances, especially where disconnect / reconnect are 351 * supported, our host also has an ID on the SCSI bus. If this is 352 * the case, then it must be reserved. Please set this_id to -1 if 353 * your setup is in single initiator mode, and the host lacks an 354 * ID. 355 */ 356 int this_id; 357 358 /* 359 * This determines the degree to which the host adapter is capable 360 * of scatter-gather. 361 */ 362 unsigned short sg_tablesize; 363 unsigned short sg_prot_tablesize; 364 365 /* 366 * Set this if the host adapter has limitations beside segment count. 367 */ 368 unsigned int max_sectors; 369 370 /* 371 * Maximum size in bytes of a single segment. 372 */ 373 unsigned int max_segment_size; 374 375 /* 376 * DMA scatter gather segment boundary limit. A segment crossing this 377 * boundary will be split in two. 378 */ 379 unsigned long dma_boundary; 380 381 unsigned long virt_boundary_mask; 382 383 /* 384 * This specifies "machine infinity" for host templates which don't 385 * limit the transfer size. Note this limit represents an absolute 386 * maximum, and may be over the transfer limits allowed for 387 * individual devices (e.g. 256 for SCSI-1). 388 */ 389 #define SCSI_DEFAULT_MAX_SECTORS 1024 390 391 /* 392 * True if this host adapter can make good use of linked commands. 393 * This will allow more than one command to be queued to a given 394 * unit on a given host. Set this to the maximum number of command 395 * blocks to be provided for each device. Set this to 1 for one 396 * command block per lun, 2 for two, etc. Do not set this to 0. 397 * You should make sure that the host adapter will do the right thing 398 * before you try setting this above 1. 399 */ 400 short cmd_per_lun; 401 402 /* 403 * present contains counter indicating how many boards of this 404 * type were found when we did the scan. 405 */ 406 unsigned char present; 407 408 /* If use block layer to manage tags, this is tag allocation policy */ 409 int tag_alloc_policy; 410 411 /* 412 * Track QUEUE_FULL events and reduce queue depth on demand. 413 */ 414 unsigned track_queue_depth:1; 415 416 /* 417 * This specifies the mode that a LLD supports. 418 */ 419 unsigned supported_mode:2; 420 421 /* 422 * True if this host adapter uses unchecked DMA onto an ISA bus. 423 */ 424 unsigned unchecked_isa_dma:1; 425 426 /* 427 * True for emulated SCSI host adapters (e.g. ATAPI). 428 */ 429 unsigned emulated:1; 430 431 /* 432 * True if the low-level driver performs its own reset-settle delays. 433 */ 434 unsigned skip_settle_delay:1; 435 436 /* True if the controller does not support WRITE SAME */ 437 unsigned no_write_same:1; 438 439 /* True if the host uses host-wide tagspace */ 440 unsigned host_tagset:1; 441 442 /* 443 * Countdown for host blocking with no commands outstanding. 444 */ 445 unsigned int max_host_blocked; 446 447 /* 448 * Default value for the blocking. If the queue is empty, 449 * host_blocked counts down in the request_fn until it restarts 450 * host operations as zero is reached. 451 * 452 * FIXME: This should probably be a value in the template 453 */ 454 #define SCSI_DEFAULT_HOST_BLOCKED 7 455 456 /* 457 * Pointer to the sysfs class properties for this host, NULL terminated. 458 */ 459 struct device_attribute **shost_attrs; 460 461 /* 462 * Pointer to the SCSI device properties for this host, NULL terminated. 463 */ 464 struct device_attribute **sdev_attrs; 465 466 /* 467 * Pointer to the SCSI device attribute groups for this host, 468 * NULL terminated. 469 */ 470 const struct attribute_group **sdev_groups; 471 472 /* 473 * Vendor Identifier associated with the host 474 * 475 * Note: When specifying vendor_id, be sure to read the 476 * Vendor Type and ID formatting requirements specified in 477 * scsi_netlink.h 478 */ 479 u64 vendor_id; 480 481 /* 482 * Additional per-command data allocated for the driver. 483 */ 484 unsigned int cmd_size; 485 struct scsi_host_cmd_pool *cmd_pool; 486 487 /* Delay for runtime autosuspend */ 488 int rpm_autosuspend_delay; 489 }; 490 491 /* 492 * Temporary #define for host lock push down. Can be removed when all 493 * drivers have been updated to take advantage of unlocked 494 * queuecommand. 495 * 496 */ 497 #define DEF_SCSI_QCMD(func_name) \ 498 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 499 { \ 500 unsigned long irq_flags; \ 501 int rc; \ 502 spin_lock_irqsave(shost->host_lock, irq_flags); \ 503 rc = func_name##_lck (cmd, cmd->scsi_done); \ 504 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 505 return rc; \ 506 } 507 508 509 /* 510 * shost state: If you alter this, you also need to alter scsi_sysfs.c 511 * (for the ascii descriptions) and the state model enforcer: 512 * scsi_host_set_state() 513 */ 514 enum scsi_host_state { 515 SHOST_CREATED = 1, 516 SHOST_RUNNING, 517 SHOST_CANCEL, 518 SHOST_DEL, 519 SHOST_RECOVERY, 520 SHOST_CANCEL_RECOVERY, 521 SHOST_DEL_RECOVERY, 522 }; 523 524 struct Scsi_Host { 525 /* 526 * __devices is protected by the host_lock, but you should 527 * usually use scsi_device_lookup / shost_for_each_device 528 * to access it and don't care about locking yourself. 529 * In the rare case of being in irq context you can use 530 * their __ prefixed variants with the lock held. NEVER 531 * access this list directly from a driver. 532 */ 533 struct list_head __devices; 534 struct list_head __targets; 535 536 struct list_head starved_list; 537 538 spinlock_t default_lock; 539 spinlock_t *host_lock; 540 541 struct mutex scan_mutex;/* serialize scanning activity */ 542 543 struct list_head eh_cmd_q; 544 struct task_struct * ehandler; /* Error recovery thread. */ 545 struct completion * eh_action; /* Wait for specific actions on the 546 host. */ 547 wait_queue_head_t host_wait; 548 struct scsi_host_template *hostt; 549 struct scsi_transport_template *transportt; 550 551 /* Area to keep a shared tag map */ 552 struct blk_mq_tag_set tag_set; 553 554 atomic_t host_blocked; 555 556 unsigned int host_failed; /* commands that failed. 557 protected by host_lock */ 558 unsigned int host_eh_scheduled; /* EH scheduled without command */ 559 560 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 561 562 /* next two fields are used to bound the time spent in error handling */ 563 int eh_deadline; 564 unsigned long last_reset; 565 566 567 /* 568 * These three parameters can be used to allow for wide scsi, 569 * and for host adapters that support multiple busses 570 * The last two should be set to 1 more than the actual max id 571 * or lun (e.g. 8 for SCSI parallel systems). 572 */ 573 unsigned int max_channel; 574 unsigned int max_id; 575 u64 max_lun; 576 577 /* 578 * This is a unique identifier that must be assigned so that we 579 * have some way of identifying each detected host adapter properly 580 * and uniquely. For hosts that do not support more than one card 581 * in the system at one time, this does not need to be set. It is 582 * initialized to 0 in scsi_register. 583 */ 584 unsigned int unique_id; 585 586 /* 587 * The maximum length of SCSI commands that this host can accept. 588 * Probably 12 for most host adapters, but could be 16 for others. 589 * or 260 if the driver supports variable length cdbs. 590 * For drivers that don't set this field, a value of 12 is 591 * assumed. 592 */ 593 unsigned short max_cmd_len; 594 595 int this_id; 596 int can_queue; 597 short cmd_per_lun; 598 short unsigned int sg_tablesize; 599 short unsigned int sg_prot_tablesize; 600 unsigned int max_sectors; 601 unsigned int max_segment_size; 602 unsigned long dma_boundary; 603 unsigned long virt_boundary_mask; 604 /* 605 * In scsi-mq mode, the number of hardware queues supported by the LLD. 606 * 607 * Note: it is assumed that each hardware queue has a queue depth of 608 * can_queue. In other words, the total queue depth per host 609 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 610 * the total queue depth is can_queue. 611 */ 612 unsigned nr_hw_queues; 613 unsigned active_mode:2; 614 unsigned unchecked_isa_dma:1; 615 616 /* 617 * Host has requested that no further requests come through for the 618 * time being. 619 */ 620 unsigned host_self_blocked:1; 621 622 /* 623 * Host uses correct SCSI ordering not PC ordering. The bit is 624 * set for the minority of drivers whose authors actually read 625 * the spec ;). 626 */ 627 unsigned reverse_ordering:1; 628 629 /* Task mgmt function in progress */ 630 unsigned tmf_in_progress:1; 631 632 /* Asynchronous scan in progress */ 633 unsigned async_scan:1; 634 635 /* Don't resume host in EH */ 636 unsigned eh_noresume:1; 637 638 /* The controller does not support WRITE SAME */ 639 unsigned no_write_same:1; 640 641 /* True if the host uses host-wide tagspace */ 642 unsigned host_tagset:1; 643 644 /* Host responded with short (<36 bytes) INQUIRY result */ 645 unsigned short_inquiry:1; 646 647 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 648 unsigned no_scsi2_lun_in_cdb:1; 649 650 /* 651 * Optional work queue to be utilized by the transport 652 */ 653 char work_q_name[20]; 654 struct workqueue_struct *work_q; 655 656 /* 657 * Task management function work queue 658 */ 659 struct workqueue_struct *tmf_work_q; 660 661 /* 662 * Value host_blocked counts down from 663 */ 664 unsigned int max_host_blocked; 665 666 /* Protection Information */ 667 unsigned int prot_capabilities; 668 unsigned char prot_guard_type; 669 670 /* legacy crap */ 671 unsigned long base; 672 unsigned long io_port; 673 unsigned char n_io_port; 674 unsigned char dma_channel; 675 unsigned int irq; 676 677 678 enum scsi_host_state shost_state; 679 680 /* ldm bits */ 681 struct device shost_gendev, shost_dev; 682 683 /* 684 * Points to the transport data (if any) which is allocated 685 * separately 686 */ 687 void *shost_data; 688 689 /* 690 * Points to the physical bus device we'd use to do DMA 691 * Needed just in case we have virtual hosts. 692 */ 693 struct device *dma_dev; 694 695 /* 696 * We should ensure that this is aligned, both for better performance 697 * and also because some compilers (m68k) don't automatically force 698 * alignment to a long boundary. 699 */ 700 unsigned long hostdata[] /* Used for storage of host specific stuff */ 701 __attribute__ ((aligned (sizeof(unsigned long)))); 702 }; 703 704 #define class_to_shost(d) \ 705 container_of(d, struct Scsi_Host, shost_dev) 706 707 #define shost_printk(prefix, shost, fmt, a...) \ 708 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 709 710 static inline void *shost_priv(struct Scsi_Host *shost) 711 { 712 return (void *)shost->hostdata; 713 } 714 715 int scsi_is_host_device(const struct device *); 716 717 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 718 { 719 while (!scsi_is_host_device(dev)) { 720 if (!dev->parent) 721 return NULL; 722 dev = dev->parent; 723 } 724 return container_of(dev, struct Scsi_Host, shost_gendev); 725 } 726 727 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 728 { 729 return shost->shost_state == SHOST_RECOVERY || 730 shost->shost_state == SHOST_CANCEL_RECOVERY || 731 shost->shost_state == SHOST_DEL_RECOVERY || 732 shost->tmf_in_progress; 733 } 734 735 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 736 extern void scsi_flush_work(struct Scsi_Host *); 737 738 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); 739 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 740 struct device *, 741 struct device *); 742 extern void scsi_scan_host(struct Scsi_Host *); 743 extern void scsi_rescan_device(struct device *); 744 extern void scsi_remove_host(struct Scsi_Host *); 745 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 746 extern int scsi_host_busy(struct Scsi_Host *shost); 747 extern void scsi_host_put(struct Scsi_Host *t); 748 extern struct Scsi_Host *scsi_host_lookup(unsigned short); 749 extern const char *scsi_host_state_name(enum scsi_host_state); 750 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 751 int status); 752 753 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 754 struct device *dev) 755 { 756 return scsi_add_host_with_dma(host, dev, dev); 757 } 758 759 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 760 { 761 return shost->shost_gendev.parent; 762 } 763 764 /** 765 * scsi_host_scan_allowed - Is scanning of this host allowed 766 * @shost: Pointer to Scsi_Host. 767 **/ 768 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 769 { 770 return shost->shost_state == SHOST_RUNNING || 771 shost->shost_state == SHOST_RECOVERY; 772 } 773 774 extern void scsi_unblock_requests(struct Scsi_Host *); 775 extern void scsi_block_requests(struct Scsi_Host *); 776 extern int scsi_host_block(struct Scsi_Host *shost); 777 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 778 779 void scsi_host_busy_iter(struct Scsi_Host *, 780 bool (*fn)(struct scsi_cmnd *, void *, bool), void *priv); 781 782 struct class_container; 783 784 /* 785 * These two functions are used to allocate and free a pseudo device 786 * which will connect to the host adapter itself rather than any 787 * physical device. You must deallocate when you are done with the 788 * thing. This physical pseudo-device isn't real and won't be available 789 * from any high-level drivers. 790 */ 791 extern void scsi_free_host_dev(struct scsi_device *); 792 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); 793 794 /* 795 * DIF defines the exchange of protection information between 796 * initiator and SBC block device. 797 * 798 * DIX defines the exchange of protection information between OS and 799 * initiator. 800 */ 801 enum scsi_host_prot_capabilities { 802 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 803 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 804 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 805 806 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 807 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 808 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 809 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 810 }; 811 812 /* 813 * SCSI hosts which support the Data Integrity Extensions must 814 * indicate their capabilities by setting the prot_capabilities using 815 * this call. 816 */ 817 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 818 { 819 shost->prot_capabilities = mask; 820 } 821 822 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 823 { 824 return shost->prot_capabilities; 825 } 826 827 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 828 { 829 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 830 } 831 832 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 833 { 834 static unsigned char cap[] = { 0, 835 SHOST_DIF_TYPE1_PROTECTION, 836 SHOST_DIF_TYPE2_PROTECTION, 837 SHOST_DIF_TYPE3_PROTECTION }; 838 839 if (target_type >= ARRAY_SIZE(cap)) 840 return 0; 841 842 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 843 } 844 845 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 846 { 847 #if defined(CONFIG_BLK_DEV_INTEGRITY) 848 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 849 SHOST_DIX_TYPE1_PROTECTION, 850 SHOST_DIX_TYPE2_PROTECTION, 851 SHOST_DIX_TYPE3_PROTECTION }; 852 853 if (target_type >= ARRAY_SIZE(cap)) 854 return 0; 855 856 return shost->prot_capabilities & cap[target_type]; 857 #endif 858 return 0; 859 } 860 861 /* 862 * All DIX-capable initiators must support the T10-mandated CRC 863 * checksum. Controllers can optionally implement the IP checksum 864 * scheme which has much lower impact on system performance. Note 865 * that the main rationale for the checksum is to match integrity 866 * metadata with data. Detecting bit errors are a job for ECC memory 867 * and buses. 868 */ 869 870 enum scsi_host_guard_type { 871 SHOST_DIX_GUARD_CRC = 1 << 0, 872 SHOST_DIX_GUARD_IP = 1 << 1, 873 }; 874 875 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 876 { 877 shost->prot_guard_type = type; 878 } 879 880 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 881 { 882 return shost->prot_guard_type; 883 } 884 885 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 886 887 #endif /* _SCSI_SCSI_HOST_H */ 888