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_transport_template; 23 24 25 #define SG_ALL SG_CHUNK_SIZE 26 27 #define MODE_UNKNOWN 0x00 28 #define MODE_INITIATOR 0x01 29 #define MODE_TARGET 0x02 30 31 struct scsi_host_template { 32 /* 33 * Put fields referenced in IO submission path together in 34 * same cacheline 35 */ 36 37 /* 38 * Additional per-command data allocated for the driver. 39 */ 40 unsigned int cmd_size; 41 42 /* 43 * The queuecommand function is used to queue up a scsi 44 * command block to the LLDD. When the driver finished 45 * processing the command the done callback is invoked. 46 * 47 * If queuecommand returns 0, then the driver has accepted the 48 * command. It must also push it to the HBA if the scsi_cmnd 49 * flag SCMD_LAST is set, or if the driver does not implement 50 * commit_rqs. The done() function must be called on the command 51 * when the driver has finished with it. (you may call done on the 52 * command before queuecommand returns, but in this case you 53 * *must* return 0 from queuecommand). 54 * 55 * Queuecommand may also reject the command, in which case it may 56 * not touch the command and must not call done() for it. 57 * 58 * There are two possible rejection returns: 59 * 60 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 61 * allow commands to other devices serviced by this host. 62 * 63 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 64 * host temporarily. 65 * 66 * For compatibility, any other non-zero return is treated the 67 * same as SCSI_MLQUEUE_HOST_BUSY. 68 * 69 * NOTE: "temporarily" means either until the next command for# 70 * this device/host completes, or a period of time determined by 71 * I/O pressure in the system if there are no other outstanding 72 * commands. 73 * 74 * STATUS: REQUIRED 75 */ 76 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); 77 78 /* 79 * The commit_rqs function is used to trigger a hardware 80 * doorbell after some requests have been queued with 81 * queuecommand, when an error is encountered before sending 82 * the request with SCMD_LAST set. 83 * 84 * STATUS: OPTIONAL 85 */ 86 void (*commit_rqs)(struct Scsi_Host *, u16); 87 88 struct module *module; 89 const char *name; 90 91 /* 92 * The info function will return whatever useful information the 93 * developer sees fit. If not provided, then the name field will 94 * be used instead. 95 * 96 * Status: OPTIONAL 97 */ 98 const char *(*info)(struct Scsi_Host *); 99 100 /* 101 * Ioctl interface 102 * 103 * Status: OPTIONAL 104 */ 105 int (*ioctl)(struct scsi_device *dev, unsigned int cmd, 106 void __user *arg); 107 108 109 #ifdef CONFIG_COMPAT 110 /* 111 * Compat handler. Handle 32bit ABI. 112 * When unknown ioctl is passed return -ENOIOCTLCMD. 113 * 114 * Status: OPTIONAL 115 */ 116 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, 117 void __user *arg); 118 #endif 119 120 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 121 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 122 123 /* 124 * This is an error handling strategy routine. You don't need to 125 * define one of these if you don't want to - there is a default 126 * routine that is present that should work in most cases. For those 127 * driver authors that have the inclination and ability to write their 128 * own strategy routine, this is where it is specified. Note - the 129 * strategy routine is *ALWAYS* run in the context of the kernel eh 130 * thread. Thus you are guaranteed to *NOT* be in an interrupt 131 * handler when you execute this, and you are also guaranteed to 132 * *NOT* have any other commands being queued while you are in the 133 * strategy routine. When you return from this function, operations 134 * return to normal. 135 * 136 * See scsi_error.c scsi_unjam_host for additional comments about 137 * what this function should and should not be attempting to do. 138 * 139 * Status: REQUIRED (at least one of them) 140 */ 141 int (* eh_abort_handler)(struct scsi_cmnd *); 142 int (* eh_device_reset_handler)(struct scsi_cmnd *); 143 int (* eh_target_reset_handler)(struct scsi_cmnd *); 144 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 145 int (* eh_host_reset_handler)(struct scsi_cmnd *); 146 147 /* 148 * Before the mid layer attempts to scan for a new device where none 149 * currently exists, it will call this entry in your driver. Should 150 * your driver need to allocate any structs or perform any other init 151 * items in order to send commands to a currently unused target/lun 152 * combo, then this is where you can perform those allocations. This 153 * is specifically so that drivers won't have to perform any kind of 154 * "is this a new device" checks in their queuecommand routine, 155 * thereby making the hot path a bit quicker. 156 * 157 * Return values: 0 on success, non-0 on failure 158 * 159 * Deallocation: If we didn't find any devices at this ID, you will 160 * get an immediate call to slave_destroy(). If we find something 161 * here then you will get a call to slave_configure(), then the 162 * device will be used for however long it is kept around, then when 163 * the device is removed from the system (or * possibly at reboot 164 * time), you will then get a call to slave_destroy(). This is 165 * assuming you implement slave_configure and slave_destroy. 166 * However, if you allocate memory and hang it off the device struct, 167 * then you must implement the slave_destroy() routine at a minimum 168 * in order to avoid leaking memory 169 * each time a device is tore down. 170 * 171 * Status: OPTIONAL 172 */ 173 int (* slave_alloc)(struct scsi_device *); 174 175 /* 176 * Once the device has responded to an INQUIRY and we know the 177 * device is online, we call into the low level driver with the 178 * struct scsi_device *. If the low level device driver implements 179 * this function, it *must* perform the task of setting the queue 180 * depth on the device. All other tasks are optional and depend 181 * on what the driver supports and various implementation details. 182 * 183 * Things currently recommended to be handled at this time include: 184 * 185 * 1. Setting the device queue depth. Proper setting of this is 186 * described in the comments for scsi_change_queue_depth. 187 * 2. Determining if the device supports the various synchronous 188 * negotiation protocols. The device struct will already have 189 * responded to INQUIRY and the results of the standard items 190 * will have been shoved into the various device flag bits, eg. 191 * device->sdtr will be true if the device supports SDTR messages. 192 * 3. Allocating command structs that the device will need. 193 * 4. Setting the default timeout on this device (if needed). 194 * 5. Anything else the low level driver might want to do on a device 195 * specific setup basis... 196 * 6. Return 0 on success, non-0 on error. The device will be marked 197 * as offline on error so that no access will occur. If you return 198 * non-0, your slave_destroy routine will never get called for this 199 * device, so don't leave any loose memory hanging around, clean 200 * up after yourself before returning non-0 201 * 202 * Status: OPTIONAL 203 */ 204 int (* slave_configure)(struct scsi_device *); 205 206 /* 207 * Immediately prior to deallocating the device and after all activity 208 * has ceased the mid layer calls this point so that the low level 209 * driver may completely detach itself from the scsi device and vice 210 * versa. The low level driver is responsible for freeing any memory 211 * it allocated in the slave_alloc or slave_configure calls. 212 * 213 * Status: OPTIONAL 214 */ 215 void (* slave_destroy)(struct scsi_device *); 216 217 /* 218 * Before the mid layer attempts to scan for a new device attached 219 * to a target where no target currently exists, it will call this 220 * entry in your driver. Should your driver need to allocate any 221 * structs or perform any other init items in order to send commands 222 * to a currently unused target, then this is where you can perform 223 * those allocations. 224 * 225 * Return values: 0 on success, non-0 on failure 226 * 227 * Status: OPTIONAL 228 */ 229 int (* target_alloc)(struct scsi_target *); 230 231 /* 232 * Immediately prior to deallocating the target structure, and 233 * after all activity to attached scsi devices has ceased, the 234 * midlayer calls this point so that the driver may deallocate 235 * and terminate any references to the target. 236 * 237 * Status: OPTIONAL 238 */ 239 void (* target_destroy)(struct scsi_target *); 240 241 /* 242 * If a host has the ability to discover targets on its own instead 243 * of scanning the entire bus, it can fill in this function and 244 * call scsi_scan_host(). This function will be called periodically 245 * until it returns 1 with the scsi_host and the elapsed time of 246 * the scan in jiffies. 247 * 248 * Status: OPTIONAL 249 */ 250 int (* scan_finished)(struct Scsi_Host *, unsigned long); 251 252 /* 253 * If the host wants to be called before the scan starts, but 254 * after the midlayer has set up ready for the scan, it can fill 255 * in this function. 256 * 257 * Status: OPTIONAL 258 */ 259 void (* scan_start)(struct Scsi_Host *); 260 261 /* 262 * Fill in this function to allow the queue depth of this host 263 * to be changeable (on a per device basis). Returns either 264 * the current queue depth setting (may be different from what 265 * was passed in) or an error. An error should only be 266 * returned if the requested depth is legal but the driver was 267 * unable to set it. If the requested depth is illegal, the 268 * driver should set and return the closest legal queue depth. 269 * 270 * Status: OPTIONAL 271 */ 272 int (* change_queue_depth)(struct scsi_device *, int); 273 274 /* 275 * This functions lets the driver expose the queue mapping 276 * to the block layer. 277 * 278 * Status: OPTIONAL 279 */ 280 int (* map_queues)(struct Scsi_Host *shost); 281 282 /* 283 * SCSI interface of blk_poll - poll for IO completions. 284 * Only applicable if SCSI LLD exposes multiple h/w queues. 285 * 286 * Return value: Number of completed entries found. 287 * 288 * Status: OPTIONAL 289 */ 290 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num); 291 292 /* 293 * Check if scatterlists need to be padded for DMA draining. 294 * 295 * Status: OPTIONAL 296 */ 297 bool (* dma_need_drain)(struct request *rq); 298 299 /* 300 * This function determines the BIOS parameters for a given 301 * harddisk. These tend to be numbers that are made up by 302 * the host adapter. Parameters: 303 * size, device, list (heads, sectors, cylinders) 304 * 305 * Status: OPTIONAL 306 */ 307 int (* bios_param)(struct scsi_device *, struct block_device *, 308 sector_t, int []); 309 310 /* 311 * This function is called when one or more partitions on the 312 * device reach beyond the end of the device. 313 * 314 * Status: OPTIONAL 315 */ 316 void (*unlock_native_capacity)(struct scsi_device *); 317 318 /* 319 * Can be used to export driver statistics and other infos to the 320 * world outside the kernel ie. userspace and it also provides an 321 * interface to feed the driver with information. 322 * 323 * Status: OBSOLETE 324 */ 325 int (*show_info)(struct seq_file *, struct Scsi_Host *); 326 int (*write_info)(struct Scsi_Host *, char *, int); 327 328 /* 329 * This is an optional routine that allows the transport to become 330 * involved when a scsi io timer fires. The return value tells the 331 * timer routine how to finish the io timeout handling. 332 * 333 * Status: OPTIONAL 334 */ 335 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 336 /* 337 * Optional routine that allows the transport to decide if a cmd 338 * is retryable. Return true if the transport is in a state the 339 * cmd should be retried on. 340 */ 341 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 342 343 /* This is an optional routine that allows transport to initiate 344 * LLD adapter or firmware reset using sysfs attribute. 345 * 346 * Return values: 0 on success, -ve value on failure. 347 * 348 * Status: OPTIONAL 349 */ 350 351 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 352 #define SCSI_ADAPTER_RESET 1 353 #define SCSI_FIRMWARE_RESET 2 354 355 356 /* 357 * Name of proc directory 358 */ 359 const char *proc_name; 360 361 /* 362 * Used to store the procfs directory if a driver implements the 363 * show_info method. 364 */ 365 struct proc_dir_entry *proc_dir; 366 367 /* 368 * This determines if we will use a non-interrupt driven 369 * or an interrupt driven scheme. It is set to the maximum number 370 * of simultaneous commands a single hw queue in HBA will accept. 371 */ 372 int can_queue; 373 374 /* 375 * In many instances, especially where disconnect / reconnect are 376 * supported, our host also has an ID on the SCSI bus. If this is 377 * the case, then it must be reserved. Please set this_id to -1 if 378 * your setup is in single initiator mode, and the host lacks an 379 * ID. 380 */ 381 int this_id; 382 383 /* 384 * This determines the degree to which the host adapter is capable 385 * of scatter-gather. 386 */ 387 unsigned short sg_tablesize; 388 unsigned short sg_prot_tablesize; 389 390 /* 391 * Set this if the host adapter has limitations beside segment count. 392 */ 393 unsigned int max_sectors; 394 395 /* 396 * Maximum size in bytes of a single segment. 397 */ 398 unsigned int max_segment_size; 399 400 /* 401 * DMA scatter gather segment boundary limit. A segment crossing this 402 * boundary will be split in two. 403 */ 404 unsigned long dma_boundary; 405 406 unsigned long virt_boundary_mask; 407 408 /* 409 * This specifies "machine infinity" for host templates which don't 410 * limit the transfer size. Note this limit represents an absolute 411 * maximum, and may be over the transfer limits allowed for 412 * individual devices (e.g. 256 for SCSI-1). 413 */ 414 #define SCSI_DEFAULT_MAX_SECTORS 1024 415 416 /* 417 * True if this host adapter can make good use of linked commands. 418 * This will allow more than one command to be queued to a given 419 * unit on a given host. Set this to the maximum number of command 420 * blocks to be provided for each device. Set this to 1 for one 421 * command block per lun, 2 for two, etc. Do not set this to 0. 422 * You should make sure that the host adapter will do the right thing 423 * before you try setting this above 1. 424 */ 425 short cmd_per_lun; 426 427 /* 428 * present contains counter indicating how many boards of this 429 * type were found when we did the scan. 430 */ 431 unsigned char present; 432 433 /* If use block layer to manage tags, this is tag allocation policy */ 434 int tag_alloc_policy; 435 436 /* 437 * Track QUEUE_FULL events and reduce queue depth on demand. 438 */ 439 unsigned track_queue_depth:1; 440 441 /* 442 * This specifies the mode that a LLD supports. 443 */ 444 unsigned supported_mode:2; 445 446 /* 447 * True for emulated SCSI host adapters (e.g. ATAPI). 448 */ 449 unsigned emulated:1; 450 451 /* 452 * True if the low-level driver performs its own reset-settle delays. 453 */ 454 unsigned skip_settle_delay:1; 455 456 /* True if the controller does not support WRITE SAME */ 457 unsigned no_write_same:1; 458 459 /* True if the host uses host-wide tagspace */ 460 unsigned host_tagset:1; 461 462 /* 463 * Countdown for host blocking with no commands outstanding. 464 */ 465 unsigned int max_host_blocked; 466 467 /* 468 * Default value for the blocking. If the queue is empty, 469 * host_blocked counts down in the request_fn until it restarts 470 * host operations as zero is reached. 471 * 472 * FIXME: This should probably be a value in the template 473 */ 474 #define SCSI_DEFAULT_HOST_BLOCKED 7 475 476 /* 477 * Pointer to the sysfs class properties for this host, NULL terminated. 478 */ 479 struct device_attribute **shost_attrs; 480 481 /* 482 * Pointer to the SCSI device properties for this host, NULL terminated. 483 */ 484 struct device_attribute **sdev_attrs; 485 486 /* 487 * Pointer to the SCSI device attribute groups for this host, 488 * NULL terminated. 489 */ 490 const struct attribute_group **sdev_groups; 491 492 /* 493 * Vendor Identifier associated with the host 494 * 495 * Note: When specifying vendor_id, be sure to read the 496 * Vendor Type and ID formatting requirements specified in 497 * scsi_netlink.h 498 */ 499 u64 vendor_id; 500 501 struct scsi_host_cmd_pool *cmd_pool; 502 503 /* Delay for runtime autosuspend */ 504 int rpm_autosuspend_delay; 505 }; 506 507 /* 508 * Temporary #define for host lock push down. Can be removed when all 509 * drivers have been updated to take advantage of unlocked 510 * queuecommand. 511 * 512 */ 513 #define DEF_SCSI_QCMD(func_name) \ 514 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 515 { \ 516 unsigned long irq_flags; \ 517 int rc; \ 518 spin_lock_irqsave(shost->host_lock, irq_flags); \ 519 rc = func_name##_lck (cmd, cmd->scsi_done); \ 520 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 521 return rc; \ 522 } 523 524 525 /* 526 * shost state: If you alter this, you also need to alter scsi_sysfs.c 527 * (for the ascii descriptions) and the state model enforcer: 528 * scsi_host_set_state() 529 */ 530 enum scsi_host_state { 531 SHOST_CREATED = 1, 532 SHOST_RUNNING, 533 SHOST_CANCEL, 534 SHOST_DEL, 535 SHOST_RECOVERY, 536 SHOST_CANCEL_RECOVERY, 537 SHOST_DEL_RECOVERY, 538 }; 539 540 struct Scsi_Host { 541 /* 542 * __devices is protected by the host_lock, but you should 543 * usually use scsi_device_lookup / shost_for_each_device 544 * to access it and don't care about locking yourself. 545 * In the rare case of being in irq context you can use 546 * their __ prefixed variants with the lock held. NEVER 547 * access this list directly from a driver. 548 */ 549 struct list_head __devices; 550 struct list_head __targets; 551 552 struct list_head starved_list; 553 554 spinlock_t default_lock; 555 spinlock_t *host_lock; 556 557 struct mutex scan_mutex;/* serialize scanning activity */ 558 559 struct list_head eh_cmd_q; 560 struct task_struct * ehandler; /* Error recovery thread. */ 561 struct completion * eh_action; /* Wait for specific actions on the 562 host. */ 563 wait_queue_head_t host_wait; 564 struct scsi_host_template *hostt; 565 struct scsi_transport_template *transportt; 566 567 /* Area to keep a shared tag map */ 568 struct blk_mq_tag_set tag_set; 569 570 atomic_t host_blocked; 571 572 unsigned int host_failed; /* commands that failed. 573 protected by host_lock */ 574 unsigned int host_eh_scheduled; /* EH scheduled without command */ 575 576 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 577 578 /* next two fields are used to bound the time spent in error handling */ 579 int eh_deadline; 580 unsigned long last_reset; 581 582 583 /* 584 * These three parameters can be used to allow for wide scsi, 585 * and for host adapters that support multiple busses 586 * The last two should be set to 1 more than the actual max id 587 * or lun (e.g. 8 for SCSI parallel systems). 588 */ 589 unsigned int max_channel; 590 unsigned int max_id; 591 u64 max_lun; 592 593 /* 594 * This is a unique identifier that must be assigned so that we 595 * have some way of identifying each detected host adapter properly 596 * and uniquely. For hosts that do not support more than one card 597 * in the system at one time, this does not need to be set. It is 598 * initialized to 0 in scsi_register. 599 */ 600 unsigned int unique_id; 601 602 /* 603 * The maximum length of SCSI commands that this host can accept. 604 * Probably 12 for most host adapters, but could be 16 for others. 605 * or 260 if the driver supports variable length cdbs. 606 * For drivers that don't set this field, a value of 12 is 607 * assumed. 608 */ 609 unsigned short max_cmd_len; 610 611 int this_id; 612 int can_queue; 613 short cmd_per_lun; 614 short unsigned int sg_tablesize; 615 short unsigned int sg_prot_tablesize; 616 unsigned int max_sectors; 617 unsigned int max_segment_size; 618 unsigned long dma_boundary; 619 unsigned long virt_boundary_mask; 620 /* 621 * In scsi-mq mode, the number of hardware queues supported by the LLD. 622 * 623 * Note: it is assumed that each hardware queue has a queue depth of 624 * can_queue. In other words, the total queue depth per host 625 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 626 * the total queue depth is can_queue. 627 */ 628 unsigned nr_hw_queues; 629 unsigned nr_maps; 630 unsigned active_mode:2; 631 632 /* 633 * Host has requested that no further requests come through for the 634 * time being. 635 */ 636 unsigned host_self_blocked:1; 637 638 /* 639 * Host uses correct SCSI ordering not PC ordering. The bit is 640 * set for the minority of drivers whose authors actually read 641 * the spec ;). 642 */ 643 unsigned reverse_ordering:1; 644 645 /* Task mgmt function in progress */ 646 unsigned tmf_in_progress:1; 647 648 /* Asynchronous scan in progress */ 649 unsigned async_scan:1; 650 651 /* Don't resume host in EH */ 652 unsigned eh_noresume:1; 653 654 /* The controller does not support WRITE SAME */ 655 unsigned no_write_same:1; 656 657 /* True if the host uses host-wide tagspace */ 658 unsigned host_tagset:1; 659 660 /* Host responded with short (<36 bytes) INQUIRY result */ 661 unsigned short_inquiry:1; 662 663 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 664 unsigned no_scsi2_lun_in_cdb:1; 665 666 /* 667 * Optional work queue to be utilized by the transport 668 */ 669 char work_q_name[20]; 670 struct workqueue_struct *work_q; 671 672 /* 673 * Task management function work queue 674 */ 675 struct workqueue_struct *tmf_work_q; 676 677 /* 678 * Value host_blocked counts down from 679 */ 680 unsigned int max_host_blocked; 681 682 /* Protection Information */ 683 unsigned int prot_capabilities; 684 unsigned char prot_guard_type; 685 686 /* legacy crap */ 687 unsigned long base; 688 unsigned long io_port; 689 unsigned char n_io_port; 690 unsigned char dma_channel; 691 unsigned int irq; 692 693 694 enum scsi_host_state shost_state; 695 696 /* ldm bits */ 697 struct device shost_gendev, shost_dev; 698 699 /* 700 * Points to the transport data (if any) which is allocated 701 * separately 702 */ 703 void *shost_data; 704 705 /* 706 * Points to the physical bus device we'd use to do DMA 707 * Needed just in case we have virtual hosts. 708 */ 709 struct device *dma_dev; 710 711 /* 712 * We should ensure that this is aligned, both for better performance 713 * and also because some compilers (m68k) don't automatically force 714 * alignment to a long boundary. 715 */ 716 unsigned long hostdata[] /* Used for storage of host specific stuff */ 717 __attribute__ ((aligned (sizeof(unsigned long)))); 718 }; 719 720 #define class_to_shost(d) \ 721 container_of(d, struct Scsi_Host, shost_dev) 722 723 #define shost_printk(prefix, shost, fmt, a...) \ 724 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 725 726 static inline void *shost_priv(struct Scsi_Host *shost) 727 { 728 return (void *)shost->hostdata; 729 } 730 731 int scsi_is_host_device(const struct device *); 732 733 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 734 { 735 while (!scsi_is_host_device(dev)) { 736 if (!dev->parent) 737 return NULL; 738 dev = dev->parent; 739 } 740 return container_of(dev, struct Scsi_Host, shost_gendev); 741 } 742 743 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 744 { 745 return shost->shost_state == SHOST_RECOVERY || 746 shost->shost_state == SHOST_CANCEL_RECOVERY || 747 shost->shost_state == SHOST_DEL_RECOVERY || 748 shost->tmf_in_progress; 749 } 750 751 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 752 extern void scsi_flush_work(struct Scsi_Host *); 753 754 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int); 755 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 756 struct device *, 757 struct device *); 758 extern void scsi_scan_host(struct Scsi_Host *); 759 extern void scsi_rescan_device(struct device *); 760 extern void scsi_remove_host(struct Scsi_Host *); 761 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 762 extern int scsi_host_busy(struct Scsi_Host *shost); 763 extern void scsi_host_put(struct Scsi_Host *t); 764 extern struct Scsi_Host *scsi_host_lookup(unsigned short); 765 extern const char *scsi_host_state_name(enum scsi_host_state); 766 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 767 int status); 768 769 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 770 struct device *dev) 771 { 772 return scsi_add_host_with_dma(host, dev, dev); 773 } 774 775 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 776 { 777 return shost->shost_gendev.parent; 778 } 779 780 /** 781 * scsi_host_scan_allowed - Is scanning of this host allowed 782 * @shost: Pointer to Scsi_Host. 783 **/ 784 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 785 { 786 return shost->shost_state == SHOST_RUNNING || 787 shost->shost_state == SHOST_RECOVERY; 788 } 789 790 extern void scsi_unblock_requests(struct Scsi_Host *); 791 extern void scsi_block_requests(struct Scsi_Host *); 792 extern int scsi_host_block(struct Scsi_Host *shost); 793 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 794 795 void scsi_host_busy_iter(struct Scsi_Host *, 796 bool (*fn)(struct scsi_cmnd *, void *, bool), void *priv); 797 798 struct class_container; 799 800 /* 801 * These two functions are used to allocate and free a pseudo device 802 * which will connect to the host adapter itself rather than any 803 * physical device. You must deallocate when you are done with the 804 * thing. This physical pseudo-device isn't real and won't be available 805 * from any high-level drivers. 806 */ 807 extern void scsi_free_host_dev(struct scsi_device *); 808 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); 809 810 /* 811 * DIF defines the exchange of protection information between 812 * initiator and SBC block device. 813 * 814 * DIX defines the exchange of protection information between OS and 815 * initiator. 816 */ 817 enum scsi_host_prot_capabilities { 818 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 819 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 820 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 821 822 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 823 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 824 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 825 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 826 }; 827 828 /* 829 * SCSI hosts which support the Data Integrity Extensions must 830 * indicate their capabilities by setting the prot_capabilities using 831 * this call. 832 */ 833 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 834 { 835 shost->prot_capabilities = mask; 836 } 837 838 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 839 { 840 return shost->prot_capabilities; 841 } 842 843 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 844 { 845 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 846 } 847 848 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 849 { 850 static unsigned char cap[] = { 0, 851 SHOST_DIF_TYPE1_PROTECTION, 852 SHOST_DIF_TYPE2_PROTECTION, 853 SHOST_DIF_TYPE3_PROTECTION }; 854 855 if (target_type >= ARRAY_SIZE(cap)) 856 return 0; 857 858 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 859 } 860 861 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 862 { 863 #if defined(CONFIG_BLK_DEV_INTEGRITY) 864 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 865 SHOST_DIX_TYPE1_PROTECTION, 866 SHOST_DIX_TYPE2_PROTECTION, 867 SHOST_DIX_TYPE3_PROTECTION }; 868 869 if (target_type >= ARRAY_SIZE(cap)) 870 return 0; 871 872 return shost->prot_capabilities & cap[target_type]; 873 #endif 874 return 0; 875 } 876 877 /* 878 * All DIX-capable initiators must support the T10-mandated CRC 879 * checksum. Controllers can optionally implement the IP checksum 880 * scheme which has much lower impact on system performance. Note 881 * that the main rationale for the checksum is to match integrity 882 * metadata with data. Detecting bit errors are a job for ECC memory 883 * and buses. 884 */ 885 886 enum scsi_host_guard_type { 887 SHOST_DIX_GUARD_CRC = 1 << 0, 888 SHOST_DIX_GUARD_IP = 1 << 1, 889 }; 890 891 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 892 { 893 shost->prot_guard_type = type; 894 } 895 896 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 897 { 898 return shost->prot_guard_type; 899 } 900 901 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 902 903 #endif /* _SCSI_SCSI_HOST_H */ 904