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 sdev_destroy(). If we find something 172 * here then you will get a call to sdev_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 sdev_destroy(). This is 176 * assuming you implement sdev_configure and sdev_destroy. 177 * However, if you allocate memory and hang it off the device struct, 178 * then you must implement the sdev_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 (* sdev_init)(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 sdev_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 (* sdev_configure)(struct scsi_device *, struct queue_limits *lim); 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 sdev_init or sdev_configure calls. 223 * 224 * Status: OPTIONAL 225 */ 226 void (* sdev_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 * Note: This callback is called with the host lock held and hence 249 * must not sleep. 250 * 251 * Status: OPTIONAL 252 */ 253 void (* target_destroy)(struct scsi_target *); 254 255 /* 256 * If a host has the ability to discover targets on its own instead 257 * of scanning the entire bus, it can fill in this function and 258 * call scsi_scan_host(). This function will be called periodically 259 * until it returns 1 with the scsi_host and the elapsed time of 260 * the scan in jiffies. 261 * 262 * Status: OPTIONAL 263 */ 264 int (* scan_finished)(struct Scsi_Host *, unsigned long); 265 266 /* 267 * If the host wants to be called before the scan starts, but 268 * after the midlayer has set up ready for the scan, it can fill 269 * in this function. 270 * 271 * Status: OPTIONAL 272 */ 273 void (* scan_start)(struct Scsi_Host *); 274 275 /* 276 * Fill in this function to allow the queue depth of this host 277 * to be changeable (on a per device basis). Returns either 278 * the current queue depth setting (may be different from what 279 * was passed in) or an error. An error should only be 280 * returned if the requested depth is legal but the driver was 281 * unable to set it. If the requested depth is illegal, the 282 * driver should set and return the closest legal queue depth. 283 * 284 * Status: OPTIONAL 285 */ 286 int (* change_queue_depth)(struct scsi_device *, int); 287 288 /* 289 * This functions lets the driver expose the queue mapping 290 * to the block layer. 291 * 292 * Status: OPTIONAL 293 */ 294 void (* map_queues)(struct Scsi_Host *shost); 295 296 /* 297 * SCSI interface of blk_poll - poll for IO completions. 298 * Only applicable if SCSI LLD exposes multiple h/w queues. 299 * 300 * Return value: Number of completed entries found. 301 * 302 * Status: OPTIONAL 303 */ 304 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num); 305 306 /* 307 * Check if scatterlists need to be padded for DMA draining. 308 * 309 * Status: OPTIONAL 310 */ 311 bool (* dma_need_drain)(struct request *rq); 312 313 /* 314 * This function determines the BIOS parameters for a given 315 * harddisk. These tend to be numbers that are made up by 316 * the host adapter. Parameters: 317 * size, device, list (heads, sectors, cylinders) 318 * 319 * Status: OPTIONAL 320 */ 321 int (* bios_param)(struct scsi_device *, struct gendisk *, 322 sector_t, int []); 323 324 /* 325 * This function is called when one or more partitions on the 326 * device reach beyond the end of the device. 327 * 328 * Status: OPTIONAL 329 */ 330 void (*unlock_native_capacity)(struct scsi_device *); 331 332 /* 333 * Can be used to export driver statistics and other infos to the 334 * world outside the kernel ie. userspace and it also provides an 335 * interface to feed the driver with information. 336 * 337 * Status: OBSOLETE 338 */ 339 int (*show_info)(struct seq_file *, struct Scsi_Host *); 340 int (*write_info)(struct Scsi_Host *, char *, int); 341 342 /* 343 * This is an optional routine that allows the transport to become 344 * involved when a scsi io timer fires. The return value tells the 345 * timer routine how to finish the io timeout handling. 346 * 347 * Status: OPTIONAL 348 */ 349 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *); 350 /* 351 * Optional routine that allows the transport to decide if a cmd 352 * is retryable. Return true if the transport is in a state the 353 * cmd should be retried on. 354 */ 355 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 356 357 /* This is an optional routine that allows transport to initiate 358 * LLD adapter or firmware reset using sysfs attribute. 359 * 360 * Return values: 0 on success, -ve value on failure. 361 * 362 * Status: OPTIONAL 363 */ 364 365 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 366 #define SCSI_ADAPTER_RESET 1 367 #define SCSI_FIRMWARE_RESET 2 368 369 370 /* 371 * Name of proc directory 372 */ 373 const char *proc_name; 374 375 /* 376 * This determines if we will use a non-interrupt driven 377 * or an interrupt driven scheme. It is set to the maximum number 378 * of simultaneous commands a single hw queue in HBA will accept. 379 */ 380 int can_queue; 381 382 /* 383 * In many instances, especially where disconnect / reconnect are 384 * supported, our host also has an ID on the SCSI bus. If this is 385 * the case, then it must be reserved. Please set this_id to -1 if 386 * your setup is in single initiator mode, and the host lacks an 387 * ID. 388 */ 389 int this_id; 390 391 /* 392 * This determines the degree to which the host adapter is capable 393 * of scatter-gather. 394 */ 395 unsigned short sg_tablesize; 396 unsigned short sg_prot_tablesize; 397 398 /* 399 * Set this if the host adapter has limitations beside segment count. 400 */ 401 unsigned int max_sectors; 402 403 /* 404 * Maximum size in bytes of a single segment. 405 */ 406 unsigned int max_segment_size; 407 408 unsigned int dma_alignment; 409 410 /* 411 * DMA scatter gather segment boundary limit. A segment crossing this 412 * boundary will be split in two. 413 */ 414 unsigned long dma_boundary; 415 416 unsigned long virt_boundary_mask; 417 418 /* 419 * This specifies "machine infinity" for host templates which don't 420 * limit the transfer size. Note this limit represents an absolute 421 * maximum, and may be over the transfer limits allowed for 422 * individual devices (e.g. 256 for SCSI-1). 423 */ 424 #define SCSI_DEFAULT_MAX_SECTORS 1024 425 426 /* 427 * True if this host adapter can make good use of linked commands. 428 * This will allow more than one command to be queued to a given 429 * unit on a given host. Set this to the maximum number of command 430 * blocks to be provided for each device. Set this to 1 for one 431 * command block per lun, 2 for two, etc. Do not set this to 0. 432 * You should make sure that the host adapter will do the right thing 433 * before you try setting this above 1. 434 */ 435 short cmd_per_lun; 436 437 /* 438 * Allocate tags starting from last allocated tag. 439 */ 440 bool tag_alloc_policy_rr : 1; 441 442 /* 443 * Track QUEUE_FULL events and reduce queue depth on demand. 444 */ 445 unsigned track_queue_depth:1; 446 447 /* 448 * This specifies the mode that a LLD supports. 449 */ 450 unsigned supported_mode:2; 451 452 /* 453 * True for emulated SCSI host adapters (e.g. ATAPI). 454 */ 455 unsigned emulated:1; 456 457 /* 458 * True if the low-level driver performs its own reset-settle delays. 459 */ 460 unsigned skip_settle_delay:1; 461 462 /* True if the controller does not support WRITE SAME */ 463 unsigned no_write_same:1; 464 465 /* True if the host uses host-wide tagspace */ 466 unsigned host_tagset:1; 467 468 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 469 unsigned queuecommand_may_block:1; 470 471 /* 472 * Countdown for host blocking with no commands outstanding. 473 */ 474 unsigned int max_host_blocked; 475 476 /* 477 * Default value for the blocking. If the queue is empty, 478 * host_blocked counts down in the request_fn until it restarts 479 * host operations as zero is reached. 480 * 481 * FIXME: This should probably be a value in the template 482 */ 483 #define SCSI_DEFAULT_HOST_BLOCKED 7 484 485 /* 486 * Pointer to the SCSI host sysfs attribute groups, NULL terminated. 487 */ 488 const struct attribute_group **shost_groups; 489 490 /* 491 * Pointer to the SCSI device attribute groups for this host, 492 * NULL terminated. 493 */ 494 const struct attribute_group **sdev_groups; 495 496 /* 497 * Vendor Identifier associated with the host 498 * 499 * Note: When specifying vendor_id, be sure to read the 500 * Vendor Type and ID formatting requirements specified in 501 * scsi_netlink.h 502 */ 503 u64 vendor_id; 504 }; 505 506 /* 507 * Temporary #define for host lock push down. Can be removed when all 508 * drivers have been updated to take advantage of unlocked 509 * queuecommand. 510 * 511 */ 512 #define DEF_SCSI_QCMD(func_name) \ 513 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 514 { \ 515 unsigned long irq_flags; \ 516 int rc; \ 517 spin_lock_irqsave(shost->host_lock, irq_flags); \ 518 rc = func_name##_lck(cmd); \ 519 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 520 return rc; \ 521 } 522 523 524 /* 525 * shost state: If you alter this, you also need to alter scsi_sysfs.c 526 * (for the ascii descriptions) and the state model enforcer: 527 * scsi_host_set_state() 528 */ 529 enum scsi_host_state { 530 SHOST_CREATED = 1, 531 SHOST_RUNNING, 532 SHOST_CANCEL, 533 SHOST_DEL, 534 SHOST_RECOVERY, 535 SHOST_CANCEL_RECOVERY, 536 SHOST_DEL_RECOVERY, 537 }; 538 539 struct Scsi_Host { 540 /* 541 * __devices is protected by the host_lock, but you should 542 * usually use scsi_device_lookup / shost_for_each_device 543 * to access it and don't care about locking yourself. 544 * In the rare case of being in irq context you can use 545 * their __ prefixed variants with the lock held. NEVER 546 * access this list directly from a driver. 547 */ 548 struct list_head __devices; 549 struct list_head __targets; 550 551 struct list_head starved_list; 552 553 spinlock_t default_lock; 554 spinlock_t *host_lock; 555 556 struct mutex scan_mutex;/* serialize scanning activity */ 557 558 struct list_head eh_abort_list; 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 const struct scsi_host_template *hostt; 565 struct scsi_transport_template *transportt; 566 567 struct kref tagset_refcnt; 568 struct completion tagset_freed; 569 /* Area to keep a shared tag map */ 570 struct blk_mq_tag_set tag_set; 571 572 atomic_t host_blocked; 573 574 unsigned int host_failed; /* commands that failed. 575 protected by host_lock */ 576 unsigned int host_eh_scheduled; /* EH scheduled without command */ 577 578 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 579 580 /* next two fields are used to bound the time spent in error handling */ 581 int eh_deadline; 582 unsigned long last_reset; 583 584 585 /* 586 * These three parameters can be used to allow for wide scsi, 587 * and for host adapters that support multiple busses 588 * The last two should be set to 1 more than the actual max id 589 * or lun (e.g. 8 for SCSI parallel systems). 590 */ 591 unsigned int max_channel; 592 unsigned int max_id; 593 u64 max_lun; 594 595 /* 596 * This is a unique identifier that must be assigned so that we 597 * have some way of identifying each detected host adapter properly 598 * and uniquely. For hosts that do not support more than one card 599 * in the system at one time, this does not need to be set. It is 600 * initialized to 0 in scsi_host_alloc. 601 */ 602 unsigned int unique_id; 603 604 /* 605 * The maximum length of SCSI commands that this host can accept. 606 * Probably 12 for most host adapters, but could be 16 for others. 607 * or 260 if the driver supports variable length cdbs. 608 * For drivers that don't set this field, a value of 12 is 609 * assumed. 610 */ 611 unsigned short max_cmd_len; 612 613 int this_id; 614 int can_queue; 615 short cmd_per_lun; 616 short unsigned int sg_tablesize; 617 short unsigned int sg_prot_tablesize; 618 unsigned int max_sectors; 619 unsigned int opt_sectors; 620 unsigned int max_segment_size; 621 unsigned int dma_alignment; 622 unsigned long dma_boundary; 623 unsigned long virt_boundary_mask; 624 /* 625 * In scsi-mq mode, the number of hardware queues supported by the LLD. 626 * 627 * Note: it is assumed that each hardware queue has a queue depth of 628 * can_queue. In other words, the total queue depth per host 629 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 630 * the total queue depth is can_queue. 631 */ 632 unsigned nr_hw_queues; 633 unsigned nr_maps; 634 unsigned active_mode:2; 635 636 /* 637 * Host has requested that no further requests come through for the 638 * time being. 639 */ 640 unsigned host_self_blocked:1; 641 642 /* 643 * Host uses correct SCSI ordering not PC ordering. The bit is 644 * set for the minority of drivers whose authors actually read 645 * the spec ;). 646 */ 647 unsigned reverse_ordering:1; 648 649 /* Task mgmt function in progress */ 650 unsigned tmf_in_progress:1; 651 652 /* Asynchronous scan in progress */ 653 unsigned async_scan:1; 654 655 /* Don't resume host in EH */ 656 unsigned eh_noresume:1; 657 658 /* The controller does not support WRITE SAME */ 659 unsigned no_write_same:1; 660 661 /* True if the host uses host-wide tagspace */ 662 unsigned host_tagset:1; 663 664 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 665 unsigned queuecommand_may_block:1; 666 667 /* Host responded with short (<36 bytes) INQUIRY result */ 668 unsigned short_inquiry:1; 669 670 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 671 unsigned no_scsi2_lun_in_cdb:1; 672 673 /* 674 * Optional work queue to be utilized by the transport 675 */ 676 struct workqueue_struct *work_q; 677 678 /* 679 * Task management function work queue 680 */ 681 struct workqueue_struct *tmf_work_q; 682 683 /* 684 * Value host_blocked counts down from 685 */ 686 unsigned int max_host_blocked; 687 688 /* Protection Information */ 689 unsigned int prot_capabilities; 690 unsigned char prot_guard_type; 691 692 /* legacy crap */ 693 unsigned long base; 694 unsigned long io_port; 695 unsigned char n_io_port; 696 unsigned char dma_channel; 697 unsigned int irq; 698 699 700 enum scsi_host_state shost_state; 701 702 /* ldm bits */ 703 struct device shost_gendev, shost_dev; 704 705 /* 706 * Points to the transport data (if any) which is allocated 707 * separately 708 */ 709 void *shost_data; 710 711 /* 712 * Points to the physical bus device we'd use to do DMA 713 * Needed just in case we have virtual hosts. 714 */ 715 struct device *dma_dev; 716 717 /* Delay for runtime autosuspend */ 718 int rpm_autosuspend_delay; 719 720 /* 721 * We should ensure that this is aligned, both for better performance 722 * and also because some compilers (m68k) don't automatically force 723 * alignment to a long boundary. 724 */ 725 unsigned long hostdata[] /* Used for storage of host specific stuff */ 726 __attribute__ ((aligned (sizeof(unsigned long)))); 727 }; 728 729 #define class_to_shost(d) \ 730 container_of(d, struct Scsi_Host, shost_dev) 731 732 #define shost_printk(prefix, shost, fmt, a...) \ 733 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 734 735 static inline void *shost_priv(struct Scsi_Host *shost) 736 { 737 return (void *)shost->hostdata; 738 } 739 740 int scsi_is_host_device(const struct device *); 741 742 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 743 { 744 while (!scsi_is_host_device(dev)) { 745 if (!dev->parent) 746 return NULL; 747 dev = dev->parent; 748 } 749 return container_of(dev, struct Scsi_Host, shost_gendev); 750 } 751 752 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 753 { 754 return shost->shost_state == SHOST_RECOVERY || 755 shost->shost_state == SHOST_CANCEL_RECOVERY || 756 shost->shost_state == SHOST_DEL_RECOVERY || 757 shost->tmf_in_progress; 758 } 759 760 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 761 extern void scsi_flush_work(struct Scsi_Host *); 762 763 extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int); 764 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 765 struct device *, 766 struct device *); 767 #if defined(CONFIG_SCSI_PROC_FS) 768 struct proc_dir_entry * 769 scsi_template_proc_dir(const struct scsi_host_template *sht); 770 #else 771 #define scsi_template_proc_dir(sht) NULL 772 #endif 773 extern void scsi_scan_host(struct Scsi_Host *); 774 extern int scsi_resume_device(struct scsi_device *sdev); 775 extern int scsi_rescan_device(struct scsi_device *sdev); 776 extern void scsi_remove_host(struct Scsi_Host *); 777 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 778 extern int scsi_host_busy(struct Scsi_Host *shost); 779 extern void scsi_host_put(struct Scsi_Host *t); 780 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum); 781 extern const char *scsi_host_state_name(enum scsi_host_state); 782 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 783 enum scsi_host_status status); 784 785 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 786 struct device *dev) 787 { 788 return scsi_add_host_with_dma(host, dev, dev); 789 } 790 791 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 792 { 793 return shost->shost_gendev.parent; 794 } 795 796 /** 797 * scsi_host_scan_allowed - Is scanning of this host allowed 798 * @shost: Pointer to Scsi_Host. 799 **/ 800 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 801 { 802 return shost->shost_state == SHOST_RUNNING || 803 shost->shost_state == SHOST_RECOVERY; 804 } 805 806 extern void scsi_unblock_requests(struct Scsi_Host *); 807 extern void scsi_block_requests(struct Scsi_Host *); 808 extern int scsi_host_block(struct Scsi_Host *shost); 809 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 810 811 void scsi_host_busy_iter(struct Scsi_Host *, 812 bool (*fn)(struct scsi_cmnd *, void *), void *priv); 813 814 struct class_container; 815 816 /* 817 * DIF defines the exchange of protection information between 818 * initiator and SBC block device. 819 * 820 * DIX defines the exchange of protection information between OS and 821 * initiator. 822 */ 823 enum scsi_host_prot_capabilities { 824 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 825 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 826 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 827 828 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 829 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 830 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 831 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 832 }; 833 834 /* 835 * SCSI hosts which support the Data Integrity Extensions must 836 * indicate their capabilities by setting the prot_capabilities using 837 * this call. 838 */ 839 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 840 { 841 shost->prot_capabilities = mask; 842 } 843 844 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 845 { 846 return shost->prot_capabilities; 847 } 848 849 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 850 { 851 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 852 } 853 854 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 855 { 856 static unsigned char cap[] = { 0, 857 SHOST_DIF_TYPE1_PROTECTION, 858 SHOST_DIF_TYPE2_PROTECTION, 859 SHOST_DIF_TYPE3_PROTECTION }; 860 861 if (target_type >= ARRAY_SIZE(cap)) 862 return 0; 863 864 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 865 } 866 867 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 868 { 869 #if defined(CONFIG_BLK_DEV_INTEGRITY) 870 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 871 SHOST_DIX_TYPE1_PROTECTION, 872 SHOST_DIX_TYPE2_PROTECTION, 873 SHOST_DIX_TYPE3_PROTECTION }; 874 875 if (target_type >= ARRAY_SIZE(cap)) 876 return 0; 877 878 return shost->prot_capabilities & cap[target_type]; 879 #endif 880 return 0; 881 } 882 883 /* 884 * All DIX-capable initiators must support the T10-mandated CRC 885 * checksum. Controllers can optionally implement the IP checksum 886 * scheme which has much lower impact on system performance. Note 887 * that the main rationale for the checksum is to match integrity 888 * metadata with data. Detecting bit errors are a job for ECC memory 889 * and buses. 890 */ 891 892 enum scsi_host_guard_type { 893 SHOST_DIX_GUARD_CRC = 1 << 0, 894 SHOST_DIX_GUARD_IP = 1 << 1, 895 }; 896 897 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 898 { 899 shost->prot_guard_type = type; 900 } 901 902 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 903 { 904 return shost->prot_guard_type; 905 } 906 907 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 908 909 #endif /* _SCSI_SCSI_HOST_H */ 910