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_target; 20 struct Scsi_Host; 21 struct scsi_transport_template; 22 23 24 #define SG_ALL SG_CHUNK_SIZE 25 26 #define MODE_UNKNOWN 0x00 27 #define MODE_INITIATOR 0x01 28 #define MODE_TARGET 0x02 29 30 /** 31 * enum scsi_timeout_action - How to handle a command that timed out. 32 * @SCSI_EH_DONE: The command has already been completed. 33 * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion. 34 * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command. 35 */ 36 enum scsi_timeout_action { 37 SCSI_EH_DONE, 38 SCSI_EH_RESET_TIMER, 39 SCSI_EH_NOT_HANDLED, 40 }; 41 42 struct scsi_host_template { 43 /* 44 * Put fields referenced in IO submission path together in 45 * same cacheline 46 */ 47 48 /* 49 * Additional per-command data allocated for the driver. 50 */ 51 unsigned int cmd_size; 52 53 /* 54 * The queuecommand function is used to queue up a scsi 55 * command block to the LLDD. When the driver finished 56 * processing the command the done callback is invoked. 57 * 58 * If queuecommand returns 0, then the driver has accepted the 59 * command. It must also push it to the HBA if the scsi_cmnd 60 * flag SCMD_LAST is set, or if the driver does not implement 61 * commit_rqs. The done() function must be called on the command 62 * when the driver has finished with it. (you may call done on the 63 * command before queuecommand returns, but in this case you 64 * *must* return 0 from queuecommand). 65 * 66 * Queuecommand may also reject the command, in which case it may 67 * not touch the command and must not call done() for it. 68 * 69 * There are two possible rejection returns: 70 * 71 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 72 * allow commands to other devices serviced by this host. 73 * 74 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 75 * host temporarily. 76 * 77 * For compatibility, any other non-zero return is treated the 78 * same as SCSI_MLQUEUE_HOST_BUSY. 79 * 80 * NOTE: "temporarily" means either until the next command for# 81 * this device/host completes, or a period of time determined by 82 * I/O pressure in the system if there are no other outstanding 83 * commands. 84 * 85 * STATUS: REQUIRED 86 */ 87 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); 88 89 /* 90 * The commit_rqs function is used to trigger a hardware 91 * doorbell after some requests have been queued with 92 * queuecommand, when an error is encountered before sending 93 * the request with SCMD_LAST set. 94 * 95 * STATUS: OPTIONAL 96 */ 97 void (*commit_rqs)(struct Scsi_Host *, u16); 98 99 struct module *module; 100 const char *name; 101 102 /* 103 * The info function will return whatever useful information the 104 * developer sees fit. If not provided, then the name field will 105 * be used instead. 106 * 107 * Status: OPTIONAL 108 */ 109 const char *(*info)(struct Scsi_Host *); 110 111 /* 112 * Ioctl interface 113 * 114 * Status: OPTIONAL 115 */ 116 int (*ioctl)(struct scsi_device *dev, unsigned int cmd, 117 void __user *arg); 118 119 120 #ifdef CONFIG_COMPAT 121 /* 122 * Compat handler. Handle 32bit ABI. 123 * When unknown ioctl is passed return -ENOIOCTLCMD. 124 * 125 * Status: OPTIONAL 126 */ 127 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, 128 void __user *arg); 129 #endif 130 131 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 132 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 133 134 /* 135 * This is an error handling strategy routine. You don't need to 136 * define one of these if you don't want to - there is a default 137 * routine that is present that should work in most cases. For those 138 * driver authors that have the inclination and ability to write their 139 * own strategy routine, this is where it is specified. Note - the 140 * strategy routine is *ALWAYS* run in the context of the kernel eh 141 * thread. Thus you are guaranteed to *NOT* be in an interrupt 142 * handler when you execute this, and you are also guaranteed to 143 * *NOT* have any other commands being queued while you are in the 144 * strategy routine. When you return from this function, operations 145 * return to normal. 146 * 147 * See scsi_error.c scsi_unjam_host for additional comments about 148 * what this function should and should not be attempting to do. 149 * 150 * Status: REQUIRED (at least one of them) 151 */ 152 int (* eh_abort_handler)(struct scsi_cmnd *); 153 int (* eh_device_reset_handler)(struct scsi_cmnd *); 154 int (* eh_target_reset_handler)(struct scsi_cmnd *); 155 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 156 int (* eh_host_reset_handler)(struct scsi_cmnd *); 157 158 /* 159 * Before the mid layer attempts to scan for a new device where none 160 * currently exists, it will call this entry in your driver. Should 161 * your driver need to allocate any structs or perform any other init 162 * items in order to send commands to a currently unused target/lun 163 * combo, then this is where you can perform those allocations. This 164 * is specifically so that drivers won't have to perform any kind of 165 * "is this a new device" checks in their queuecommand routine, 166 * thereby making the hot path a bit quicker. 167 * 168 * Return values: 0 on success, non-0 on failure 169 * 170 * Deallocation: If we didn't find any devices at this ID, you will 171 * get an immediate call to slave_destroy(). If we find something 172 * here then you will get a call to slave_configure(), then the 173 * device will be used for however long it is kept around, then when 174 * the device is removed from the system (or * possibly at reboot 175 * time), you will then get a call to slave_destroy(). This is 176 * assuming you implement slave_configure and slave_destroy. 177 * However, if you allocate memory and hang it off the device struct, 178 * then you must implement the slave_destroy() routine at a minimum 179 * in order to avoid leaking memory 180 * each time a device is tore down. 181 * 182 * Status: OPTIONAL 183 */ 184 int (* slave_alloc)(struct scsi_device *); 185 186 /* 187 * Once the device has responded to an INQUIRY and we know the 188 * device is online, we call into the low level driver with the 189 * struct scsi_device *. If the low level device driver implements 190 * this function, it *must* perform the task of setting the queue 191 * depth on the device. All other tasks are optional and depend 192 * on what the driver supports and various implementation details. 193 * 194 * Things currently recommended to be handled at this time include: 195 * 196 * 1. Setting the device queue depth. Proper setting of this is 197 * described in the comments for scsi_change_queue_depth. 198 * 2. Determining if the device supports the various synchronous 199 * negotiation protocols. The device struct will already have 200 * responded to INQUIRY and the results of the standard items 201 * will have been shoved into the various device flag bits, eg. 202 * device->sdtr will be true if the device supports SDTR messages. 203 * 3. Allocating command structs that the device will need. 204 * 4. Setting the default timeout on this device (if needed). 205 * 5. Anything else the low level driver might want to do on a device 206 * specific setup basis... 207 * 6. Return 0 on success, non-0 on error. The device will be marked 208 * as offline on error so that no access will occur. If you return 209 * non-0, your slave_destroy routine will never get called for this 210 * device, so don't leave any loose memory hanging around, clean 211 * up after yourself before returning non-0 212 * 213 * Status: OPTIONAL 214 */ 215 int (* slave_configure)(struct scsi_device *); 216 217 /* 218 * Immediately prior to deallocating the device and after all activity 219 * has ceased the mid layer calls this point so that the low level 220 * driver may completely detach itself from the scsi device and vice 221 * versa. The low level driver is responsible for freeing any memory 222 * it allocated in the slave_alloc or slave_configure calls. 223 * 224 * Status: OPTIONAL 225 */ 226 void (* slave_destroy)(struct scsi_device *); 227 228 /* 229 * Before the mid layer attempts to scan for a new device attached 230 * to a target where no target currently exists, it will call this 231 * entry in your driver. Should your driver need to allocate any 232 * structs or perform any other init items in order to send commands 233 * to a currently unused target, then this is where you can perform 234 * those allocations. 235 * 236 * Return values: 0 on success, non-0 on failure 237 * 238 * Status: OPTIONAL 239 */ 240 int (* target_alloc)(struct scsi_target *); 241 242 /* 243 * Immediately prior to deallocating the target structure, and 244 * after all activity to attached scsi devices has ceased, the 245 * midlayer calls this point so that the driver may deallocate 246 * and terminate any references to the target. 247 * 248 * Status: OPTIONAL 249 */ 250 void (* target_destroy)(struct scsi_target *); 251 252 /* 253 * If a host has the ability to discover targets on its own instead 254 * of scanning the entire bus, it can fill in this function and 255 * call scsi_scan_host(). This function will be called periodically 256 * until it returns 1 with the scsi_host and the elapsed time of 257 * the scan in jiffies. 258 * 259 * Status: OPTIONAL 260 */ 261 int (* scan_finished)(struct Scsi_Host *, unsigned long); 262 263 /* 264 * If the host wants to be called before the scan starts, but 265 * after the midlayer has set up ready for the scan, it can fill 266 * in this function. 267 * 268 * Status: OPTIONAL 269 */ 270 void (* scan_start)(struct Scsi_Host *); 271 272 /* 273 * Fill in this function to allow the queue depth of this host 274 * to be changeable (on a per device basis). Returns either 275 * the current queue depth setting (may be different from what 276 * was passed in) or an error. An error should only be 277 * returned if the requested depth is legal but the driver was 278 * unable to set it. If the requested depth is illegal, the 279 * driver should set and return the closest legal queue depth. 280 * 281 * Status: OPTIONAL 282 */ 283 int (* change_queue_depth)(struct scsi_device *, int); 284 285 /* 286 * This functions lets the driver expose the queue mapping 287 * to the block layer. 288 * 289 * Status: OPTIONAL 290 */ 291 void (* map_queues)(struct Scsi_Host *shost); 292 293 /* 294 * SCSI interface of blk_poll - poll for IO completions. 295 * Only applicable if SCSI LLD exposes multiple h/w queues. 296 * 297 * Return value: Number of completed entries found. 298 * 299 * Status: OPTIONAL 300 */ 301 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num); 302 303 /* 304 * Check if scatterlists need to be padded for DMA draining. 305 * 306 * Status: OPTIONAL 307 */ 308 bool (* dma_need_drain)(struct request *rq); 309 310 /* 311 * This function determines the BIOS parameters for a given 312 * harddisk. These tend to be numbers that are made up by 313 * the host adapter. Parameters: 314 * size, device, list (heads, sectors, cylinders) 315 * 316 * Status: OPTIONAL 317 */ 318 int (* bios_param)(struct scsi_device *, struct block_device *, 319 sector_t, int []); 320 321 /* 322 * This function is called when one or more partitions on the 323 * device reach beyond the end of the device. 324 * 325 * Status: OPTIONAL 326 */ 327 void (*unlock_native_capacity)(struct scsi_device *); 328 329 /* 330 * Can be used to export driver statistics and other infos to the 331 * world outside the kernel ie. userspace and it also provides an 332 * interface to feed the driver with information. 333 * 334 * Status: OBSOLETE 335 */ 336 int (*show_info)(struct seq_file *, struct Scsi_Host *); 337 int (*write_info)(struct Scsi_Host *, char *, int); 338 339 /* 340 * This is an optional routine that allows the transport to become 341 * involved when a scsi io timer fires. The return value tells the 342 * timer routine how to finish the io timeout handling. 343 * 344 * Status: OPTIONAL 345 */ 346 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *); 347 /* 348 * Optional routine that allows the transport to decide if a cmd 349 * is retryable. Return true if the transport is in a state the 350 * cmd should be retried on. 351 */ 352 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 353 354 /* This is an optional routine that allows transport to initiate 355 * LLD adapter or firmware reset using sysfs attribute. 356 * 357 * Return values: 0 on success, -ve value on failure. 358 * 359 * Status: OPTIONAL 360 */ 361 362 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 363 #define SCSI_ADAPTER_RESET 1 364 #define SCSI_FIRMWARE_RESET 2 365 366 367 /* 368 * Name of proc directory 369 */ 370 const char *proc_name; 371 372 /* 373 * This determines if we will use a non-interrupt driven 374 * or an interrupt driven scheme. It is set to the maximum number 375 * of simultaneous commands a single hw queue in HBA will accept. 376 */ 377 int can_queue; 378 379 /* 380 * In many instances, especially where disconnect / reconnect are 381 * supported, our host also has an ID on the SCSI bus. If this is 382 * the case, then it must be reserved. Please set this_id to -1 if 383 * your setup is in single initiator mode, and the host lacks an 384 * ID. 385 */ 386 int this_id; 387 388 /* 389 * This determines the degree to which the host adapter is capable 390 * of scatter-gather. 391 */ 392 unsigned short sg_tablesize; 393 unsigned short sg_prot_tablesize; 394 395 /* 396 * Set this if the host adapter has limitations beside segment count. 397 */ 398 unsigned int max_sectors; 399 400 /* 401 * Maximum size in bytes of a single segment. 402 */ 403 unsigned int max_segment_size; 404 405 /* 406 * DMA scatter gather segment boundary limit. A segment crossing this 407 * boundary will be split in two. 408 */ 409 unsigned long dma_boundary; 410 411 unsigned long virt_boundary_mask; 412 413 /* 414 * This specifies "machine infinity" for host templates which don't 415 * limit the transfer size. Note this limit represents an absolute 416 * maximum, and may be over the transfer limits allowed for 417 * individual devices (e.g. 256 for SCSI-1). 418 */ 419 #define SCSI_DEFAULT_MAX_SECTORS 1024 420 421 /* 422 * True if this host adapter can make good use of linked commands. 423 * This will allow more than one command to be queued to a given 424 * unit on a given host. Set this to the maximum number of command 425 * blocks to be provided for each device. Set this to 1 for one 426 * command block per lun, 2 for two, etc. Do not set this to 0. 427 * You should make sure that the host adapter will do the right thing 428 * before you try setting this above 1. 429 */ 430 short cmd_per_lun; 431 432 /* If use block layer to manage tags, this is tag allocation policy */ 433 int tag_alloc_policy; 434 435 /* 436 * Track QUEUE_FULL events and reduce queue depth on demand. 437 */ 438 unsigned track_queue_depth:1; 439 440 /* 441 * This specifies the mode that a LLD supports. 442 */ 443 unsigned supported_mode:2; 444 445 /* 446 * True for emulated SCSI host adapters (e.g. ATAPI). 447 */ 448 unsigned emulated:1; 449 450 /* 451 * True if the low-level driver performs its own reset-settle delays. 452 */ 453 unsigned skip_settle_delay:1; 454 455 /* True if the controller does not support WRITE SAME */ 456 unsigned no_write_same:1; 457 458 /* True if the host uses host-wide tagspace */ 459 unsigned host_tagset:1; 460 461 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 462 unsigned queuecommand_may_block:1; 463 464 /* 465 * Countdown for host blocking with no commands outstanding. 466 */ 467 unsigned int max_host_blocked; 468 469 /* 470 * Default value for the blocking. If the queue is empty, 471 * host_blocked counts down in the request_fn until it restarts 472 * host operations as zero is reached. 473 * 474 * FIXME: This should probably be a value in the template 475 */ 476 #define SCSI_DEFAULT_HOST_BLOCKED 7 477 478 /* 479 * Pointer to the SCSI host sysfs attribute groups, NULL terminated. 480 */ 481 const struct attribute_group **shost_groups; 482 483 /* 484 * Pointer to the SCSI device attribute groups for this host, 485 * NULL terminated. 486 */ 487 const struct attribute_group **sdev_groups; 488 489 /* 490 * Vendor Identifier associated with the host 491 * 492 * Note: When specifying vendor_id, be sure to read the 493 * Vendor Type and ID formatting requirements specified in 494 * scsi_netlink.h 495 */ 496 u64 vendor_id; 497 498 /* Delay for runtime autosuspend */ 499 int rpm_autosuspend_delay; 500 }; 501 502 /* 503 * Temporary #define for host lock push down. Can be removed when all 504 * drivers have been updated to take advantage of unlocked 505 * queuecommand. 506 * 507 */ 508 #define DEF_SCSI_QCMD(func_name) \ 509 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 510 { \ 511 unsigned long irq_flags; \ 512 int rc; \ 513 spin_lock_irqsave(shost->host_lock, irq_flags); \ 514 rc = func_name##_lck(cmd); \ 515 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 516 return rc; \ 517 } 518 519 520 /* 521 * shost state: If you alter this, you also need to alter scsi_sysfs.c 522 * (for the ascii descriptions) and the state model enforcer: 523 * scsi_host_set_state() 524 */ 525 enum scsi_host_state { 526 SHOST_CREATED = 1, 527 SHOST_RUNNING, 528 SHOST_CANCEL, 529 SHOST_DEL, 530 SHOST_RECOVERY, 531 SHOST_CANCEL_RECOVERY, 532 SHOST_DEL_RECOVERY, 533 }; 534 535 struct Scsi_Host { 536 /* 537 * __devices is protected by the host_lock, but you should 538 * usually use scsi_device_lookup / shost_for_each_device 539 * to access it and don't care about locking yourself. 540 * In the rare case of being in irq context you can use 541 * their __ prefixed variants with the lock held. NEVER 542 * access this list directly from a driver. 543 */ 544 struct list_head __devices; 545 struct list_head __targets; 546 547 struct list_head starved_list; 548 549 spinlock_t default_lock; 550 spinlock_t *host_lock; 551 552 struct mutex scan_mutex;/* serialize scanning activity */ 553 554 struct list_head eh_abort_list; 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 const struct scsi_host_template *hostt; 561 struct scsi_transport_template *transportt; 562 563 struct kref tagset_refcnt; 564 struct completion tagset_freed; 565 /* Area to keep a shared tag map */ 566 struct blk_mq_tag_set tag_set; 567 568 atomic_t host_blocked; 569 570 unsigned int host_failed; /* commands that failed. 571 protected by host_lock */ 572 unsigned int host_eh_scheduled; /* EH scheduled without command */ 573 574 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 575 576 /* next two fields are used to bound the time spent in error handling */ 577 int eh_deadline; 578 unsigned long last_reset; 579 580 581 /* 582 * These three parameters can be used to allow for wide scsi, 583 * and for host adapters that support multiple busses 584 * The last two should be set to 1 more than the actual max id 585 * or lun (e.g. 8 for SCSI parallel systems). 586 */ 587 unsigned int max_channel; 588 unsigned int max_id; 589 u64 max_lun; 590 591 /* 592 * This is a unique identifier that must be assigned so that we 593 * have some way of identifying each detected host adapter properly 594 * and uniquely. For hosts that do not support more than one card 595 * in the system at one time, this does not need to be set. It is 596 * initialized to 0 in scsi_register. 597 */ 598 unsigned int unique_id; 599 600 /* 601 * The maximum length of SCSI commands that this host can accept. 602 * Probably 12 for most host adapters, but could be 16 for others. 603 * or 260 if the driver supports variable length cdbs. 604 * For drivers that don't set this field, a value of 12 is 605 * assumed. 606 */ 607 unsigned short max_cmd_len; 608 609 int this_id; 610 int can_queue; 611 short cmd_per_lun; 612 short unsigned int sg_tablesize; 613 short unsigned int sg_prot_tablesize; 614 unsigned int max_sectors; 615 unsigned int opt_sectors; 616 unsigned int max_segment_size; 617 unsigned long dma_boundary; 618 unsigned long virt_boundary_mask; 619 /* 620 * In scsi-mq mode, the number of hardware queues supported by the LLD. 621 * 622 * Note: it is assumed that each hardware queue has a queue depth of 623 * can_queue. In other words, the total queue depth per host 624 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 625 * the total queue depth is can_queue. 626 */ 627 unsigned nr_hw_queues; 628 unsigned nr_maps; 629 unsigned active_mode:2; 630 631 /* 632 * Host has requested that no further requests come through for the 633 * time being. 634 */ 635 unsigned host_self_blocked:1; 636 637 /* 638 * Host uses correct SCSI ordering not PC ordering. The bit is 639 * set for the minority of drivers whose authors actually read 640 * the spec ;). 641 */ 642 unsigned reverse_ordering:1; 643 644 /* Task mgmt function in progress */ 645 unsigned tmf_in_progress:1; 646 647 /* Asynchronous scan in progress */ 648 unsigned async_scan:1; 649 650 /* Don't resume host in EH */ 651 unsigned eh_noresume:1; 652 653 /* The controller does not support WRITE SAME */ 654 unsigned no_write_same:1; 655 656 /* True if the host uses host-wide tagspace */ 657 unsigned host_tagset:1; 658 659 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 660 unsigned queuecommand_may_block:1; 661 662 /* Host responded with short (<36 bytes) INQUIRY result */ 663 unsigned short_inquiry:1; 664 665 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 666 unsigned no_scsi2_lun_in_cdb:1; 667 668 /* 669 * Optional work queue to be utilized by the transport 670 */ 671 char work_q_name[20]; 672 struct workqueue_struct *work_q; 673 674 /* 675 * Task management function work queue 676 */ 677 struct workqueue_struct *tmf_work_q; 678 679 /* 680 * Value host_blocked counts down from 681 */ 682 unsigned int max_host_blocked; 683 684 /* Protection Information */ 685 unsigned int prot_capabilities; 686 unsigned char prot_guard_type; 687 688 /* legacy crap */ 689 unsigned long base; 690 unsigned long io_port; 691 unsigned char n_io_port; 692 unsigned char dma_channel; 693 unsigned int irq; 694 695 696 enum scsi_host_state shost_state; 697 698 /* ldm bits */ 699 struct device shost_gendev, shost_dev; 700 701 /* 702 * Points to the transport data (if any) which is allocated 703 * separately 704 */ 705 void *shost_data; 706 707 /* 708 * Points to the physical bus device we'd use to do DMA 709 * Needed just in case we have virtual hosts. 710 */ 711 struct device *dma_dev; 712 713 /* 714 * We should ensure that this is aligned, both for better performance 715 * and also because some compilers (m68k) don't automatically force 716 * alignment to a long boundary. 717 */ 718 unsigned long hostdata[] /* Used for storage of host specific stuff */ 719 __attribute__ ((aligned (sizeof(unsigned long)))); 720 }; 721 722 #define class_to_shost(d) \ 723 container_of(d, struct Scsi_Host, shost_dev) 724 725 #define shost_printk(prefix, shost, fmt, a...) \ 726 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 727 728 static inline void *shost_priv(struct Scsi_Host *shost) 729 { 730 return (void *)shost->hostdata; 731 } 732 733 int scsi_is_host_device(const struct device *); 734 735 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 736 { 737 while (!scsi_is_host_device(dev)) { 738 if (!dev->parent) 739 return NULL; 740 dev = dev->parent; 741 } 742 return container_of(dev, struct Scsi_Host, shost_gendev); 743 } 744 745 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 746 { 747 return shost->shost_state == SHOST_RECOVERY || 748 shost->shost_state == SHOST_CANCEL_RECOVERY || 749 shost->shost_state == SHOST_DEL_RECOVERY || 750 shost->tmf_in_progress; 751 } 752 753 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 754 extern void scsi_flush_work(struct Scsi_Host *); 755 756 extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int); 757 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 758 struct device *, 759 struct device *); 760 #if defined(CONFIG_SCSI_PROC_FS) 761 struct proc_dir_entry * 762 scsi_template_proc_dir(const struct scsi_host_template *sht); 763 #else 764 #define scsi_template_proc_dir(sht) NULL 765 #endif 766 extern void scsi_scan_host(struct Scsi_Host *); 767 extern void scsi_rescan_device(struct scsi_device *); 768 extern void scsi_remove_host(struct Scsi_Host *); 769 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 770 extern int scsi_host_busy(struct Scsi_Host *shost); 771 extern void scsi_host_put(struct Scsi_Host *t); 772 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum); 773 extern const char *scsi_host_state_name(enum scsi_host_state); 774 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 775 enum scsi_host_status status); 776 777 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 778 struct device *dev) 779 { 780 return scsi_add_host_with_dma(host, dev, dev); 781 } 782 783 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 784 { 785 return shost->shost_gendev.parent; 786 } 787 788 /** 789 * scsi_host_scan_allowed - Is scanning of this host allowed 790 * @shost: Pointer to Scsi_Host. 791 **/ 792 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 793 { 794 return shost->shost_state == SHOST_RUNNING || 795 shost->shost_state == SHOST_RECOVERY; 796 } 797 798 extern void scsi_unblock_requests(struct Scsi_Host *); 799 extern void scsi_block_requests(struct Scsi_Host *); 800 extern int scsi_host_block(struct Scsi_Host *shost); 801 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 802 803 void scsi_host_busy_iter(struct Scsi_Host *, 804 bool (*fn)(struct scsi_cmnd *, void *), void *priv); 805 806 struct class_container; 807 808 /* 809 * DIF defines the exchange of protection information between 810 * initiator and SBC block device. 811 * 812 * DIX defines the exchange of protection information between OS and 813 * initiator. 814 */ 815 enum scsi_host_prot_capabilities { 816 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 817 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 818 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 819 820 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 821 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 822 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 823 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 824 }; 825 826 /* 827 * SCSI hosts which support the Data Integrity Extensions must 828 * indicate their capabilities by setting the prot_capabilities using 829 * this call. 830 */ 831 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 832 { 833 shost->prot_capabilities = mask; 834 } 835 836 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 837 { 838 return shost->prot_capabilities; 839 } 840 841 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 842 { 843 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 844 } 845 846 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 847 { 848 static unsigned char cap[] = { 0, 849 SHOST_DIF_TYPE1_PROTECTION, 850 SHOST_DIF_TYPE2_PROTECTION, 851 SHOST_DIF_TYPE3_PROTECTION }; 852 853 if (target_type >= ARRAY_SIZE(cap)) 854 return 0; 855 856 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 857 } 858 859 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 860 { 861 #if defined(CONFIG_BLK_DEV_INTEGRITY) 862 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 863 SHOST_DIX_TYPE1_PROTECTION, 864 SHOST_DIX_TYPE2_PROTECTION, 865 SHOST_DIX_TYPE3_PROTECTION }; 866 867 if (target_type >= ARRAY_SIZE(cap)) 868 return 0; 869 870 return shost->prot_capabilities & cap[target_type]; 871 #endif 872 return 0; 873 } 874 875 /* 876 * All DIX-capable initiators must support the T10-mandated CRC 877 * checksum. Controllers can optionally implement the IP checksum 878 * scheme which has much lower impact on system performance. Note 879 * that the main rationale for the checksum is to match integrity 880 * metadata with data. Detecting bit errors are a job for ECC memory 881 * and buses. 882 */ 883 884 enum scsi_host_guard_type { 885 SHOST_DIX_GUARD_CRC = 1 << 0, 886 SHOST_DIX_GUARD_IP = 1 << 1, 887 }; 888 889 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 890 { 891 shost->prot_guard_type = type; 892 } 893 894 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 895 { 896 return shost->prot_guard_type; 897 } 898 899 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 900 901 #endif /* _SCSI_SCSI_HOST_H */ 902