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