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 * Note: slave_configure is the legacy version, use device_configure for 216 * all new code. A driver must never define both. 217 */ 218 int (* device_configure)(struct scsi_device *, struct queue_limits *lim); 219 int (* slave_configure)(struct scsi_device *); 220 221 /* 222 * Immediately prior to deallocating the device and after all activity 223 * has ceased the mid layer calls this point so that the low level 224 * driver may completely detach itself from the scsi device and vice 225 * versa. The low level driver is responsible for freeing any memory 226 * it allocated in the slave_alloc or slave_configure calls. 227 * 228 * Status: OPTIONAL 229 */ 230 void (* slave_destroy)(struct scsi_device *); 231 232 /* 233 * Before the mid layer attempts to scan for a new device attached 234 * to a target where no target currently exists, it will call this 235 * entry in your driver. Should your driver need to allocate any 236 * structs or perform any other init items in order to send commands 237 * to a currently unused target, then this is where you can perform 238 * those allocations. 239 * 240 * Return values: 0 on success, non-0 on failure 241 * 242 * Status: OPTIONAL 243 */ 244 int (* target_alloc)(struct scsi_target *); 245 246 /* 247 * Immediately prior to deallocating the target structure, and 248 * after all activity to attached scsi devices has ceased, the 249 * midlayer calls this point so that the driver may deallocate 250 * and terminate any references to the target. 251 * 252 * Note: This callback is called with the host lock held and hence 253 * must not sleep. 254 * 255 * Status: OPTIONAL 256 */ 257 void (* target_destroy)(struct scsi_target *); 258 259 /* 260 * If a host has the ability to discover targets on its own instead 261 * of scanning the entire bus, it can fill in this function and 262 * call scsi_scan_host(). This function will be called periodically 263 * until it returns 1 with the scsi_host and the elapsed time of 264 * the scan in jiffies. 265 * 266 * Status: OPTIONAL 267 */ 268 int (* scan_finished)(struct Scsi_Host *, unsigned long); 269 270 /* 271 * If the host wants to be called before the scan starts, but 272 * after the midlayer has set up ready for the scan, it can fill 273 * in this function. 274 * 275 * Status: OPTIONAL 276 */ 277 void (* scan_start)(struct Scsi_Host *); 278 279 /* 280 * Fill in this function to allow the queue depth of this host 281 * to be changeable (on a per device basis). Returns either 282 * the current queue depth setting (may be different from what 283 * was passed in) or an error. An error should only be 284 * returned if the requested depth is legal but the driver was 285 * unable to set it. If the requested depth is illegal, the 286 * driver should set and return the closest legal queue depth. 287 * 288 * Status: OPTIONAL 289 */ 290 int (* change_queue_depth)(struct scsi_device *, int); 291 292 /* 293 * This functions lets the driver expose the queue mapping 294 * to the block layer. 295 * 296 * Status: OPTIONAL 297 */ 298 void (* map_queues)(struct Scsi_Host *shost); 299 300 /* 301 * SCSI interface of blk_poll - poll for IO completions. 302 * Only applicable if SCSI LLD exposes multiple h/w queues. 303 * 304 * Return value: Number of completed entries found. 305 * 306 * Status: OPTIONAL 307 */ 308 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num); 309 310 /* 311 * Check if scatterlists need to be padded for DMA draining. 312 * 313 * Status: OPTIONAL 314 */ 315 bool (* dma_need_drain)(struct request *rq); 316 317 /* 318 * This function determines the BIOS parameters for a given 319 * harddisk. These tend to be numbers that are made up by 320 * the host adapter. Parameters: 321 * size, device, list (heads, sectors, cylinders) 322 * 323 * Status: OPTIONAL 324 */ 325 int (* bios_param)(struct scsi_device *, struct block_device *, 326 sector_t, int []); 327 328 /* 329 * This function is called when one or more partitions on the 330 * device reach beyond the end of the device. 331 * 332 * Status: OPTIONAL 333 */ 334 void (*unlock_native_capacity)(struct scsi_device *); 335 336 /* 337 * Can be used to export driver statistics and other infos to the 338 * world outside the kernel ie. userspace and it also provides an 339 * interface to feed the driver with information. 340 * 341 * Status: OBSOLETE 342 */ 343 int (*show_info)(struct seq_file *, struct Scsi_Host *); 344 int (*write_info)(struct Scsi_Host *, char *, int); 345 346 /* 347 * This is an optional routine that allows the transport to become 348 * involved when a scsi io timer fires. The return value tells the 349 * timer routine how to finish the io timeout handling. 350 * 351 * Status: OPTIONAL 352 */ 353 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *); 354 /* 355 * Optional routine that allows the transport to decide if a cmd 356 * is retryable. Return true if the transport is in a state the 357 * cmd should be retried on. 358 */ 359 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 360 361 /* This is an optional routine that allows transport to initiate 362 * LLD adapter or firmware reset using sysfs attribute. 363 * 364 * Return values: 0 on success, -ve value on failure. 365 * 366 * Status: OPTIONAL 367 */ 368 369 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 370 #define SCSI_ADAPTER_RESET 1 371 #define SCSI_FIRMWARE_RESET 2 372 373 374 /* 375 * Name of proc directory 376 */ 377 const char *proc_name; 378 379 /* 380 * This determines if we will use a non-interrupt driven 381 * or an interrupt driven scheme. It is set to the maximum number 382 * of simultaneous commands a single hw queue in HBA will accept. 383 */ 384 int can_queue; 385 386 /* 387 * In many instances, especially where disconnect / reconnect are 388 * supported, our host also has an ID on the SCSI bus. If this is 389 * the case, then it must be reserved. Please set this_id to -1 if 390 * your setup is in single initiator mode, and the host lacks an 391 * ID. 392 */ 393 int this_id; 394 395 /* 396 * This determines the degree to which the host adapter is capable 397 * of scatter-gather. 398 */ 399 unsigned short sg_tablesize; 400 unsigned short sg_prot_tablesize; 401 402 /* 403 * Set this if the host adapter has limitations beside segment count. 404 */ 405 unsigned int max_sectors; 406 407 /* 408 * Maximum size in bytes of a single segment. 409 */ 410 unsigned int max_segment_size; 411 412 unsigned int dma_alignment; 413 414 /* 415 * DMA scatter gather segment boundary limit. A segment crossing this 416 * boundary will be split in two. 417 */ 418 unsigned long dma_boundary; 419 420 unsigned long virt_boundary_mask; 421 422 /* 423 * This specifies "machine infinity" for host templates which don't 424 * limit the transfer size. Note this limit represents an absolute 425 * maximum, and may be over the transfer limits allowed for 426 * individual devices (e.g. 256 for SCSI-1). 427 */ 428 #define SCSI_DEFAULT_MAX_SECTORS 1024 429 430 /* 431 * True if this host adapter can make good use of linked commands. 432 * This will allow more than one command to be queued to a given 433 * unit on a given host. Set this to the maximum number of command 434 * blocks to be provided for each device. Set this to 1 for one 435 * command block per lun, 2 for two, etc. Do not set this to 0. 436 * You should make sure that the host adapter will do the right thing 437 * before you try setting this above 1. 438 */ 439 short cmd_per_lun; 440 441 /* If use block layer to manage tags, this is tag allocation policy */ 442 int tag_alloc_policy; 443 444 /* 445 * Track QUEUE_FULL events and reduce queue depth on demand. 446 */ 447 unsigned track_queue_depth:1; 448 449 /* 450 * This specifies the mode that a LLD supports. 451 */ 452 unsigned supported_mode:2; 453 454 /* 455 * True for emulated SCSI host adapters (e.g. ATAPI). 456 */ 457 unsigned emulated:1; 458 459 /* 460 * True if the low-level driver performs its own reset-settle delays. 461 */ 462 unsigned skip_settle_delay:1; 463 464 /* True if the controller does not support WRITE SAME */ 465 unsigned no_write_same:1; 466 467 /* True if the host uses host-wide tagspace */ 468 unsigned host_tagset:1; 469 470 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 471 unsigned queuecommand_may_block:1; 472 473 /* 474 * Countdown for host blocking with no commands outstanding. 475 */ 476 unsigned int max_host_blocked; 477 478 /* 479 * Default value for the blocking. If the queue is empty, 480 * host_blocked counts down in the request_fn until it restarts 481 * host operations as zero is reached. 482 * 483 * FIXME: This should probably be a value in the template 484 */ 485 #define SCSI_DEFAULT_HOST_BLOCKED 7 486 487 /* 488 * Pointer to the SCSI host sysfs attribute groups, NULL terminated. 489 */ 490 const struct attribute_group **shost_groups; 491 492 /* 493 * Pointer to the SCSI device attribute groups for this host, 494 * NULL terminated. 495 */ 496 const struct attribute_group **sdev_groups; 497 498 /* 499 * Vendor Identifier associated with the host 500 * 501 * Note: When specifying vendor_id, be sure to read the 502 * Vendor Type and ID formatting requirements specified in 503 * scsi_netlink.h 504 */ 505 u64 vendor_id; 506 }; 507 508 /* 509 * Temporary #define for host lock push down. Can be removed when all 510 * drivers have been updated to take advantage of unlocked 511 * queuecommand. 512 * 513 */ 514 #define DEF_SCSI_QCMD(func_name) \ 515 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 516 { \ 517 unsigned long irq_flags; \ 518 int rc; \ 519 spin_lock_irqsave(shost->host_lock, irq_flags); \ 520 rc = func_name##_lck(cmd); \ 521 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 522 return rc; \ 523 } 524 525 526 /* 527 * shost state: If you alter this, you also need to alter scsi_sysfs.c 528 * (for the ascii descriptions) and the state model enforcer: 529 * scsi_host_set_state() 530 */ 531 enum scsi_host_state { 532 SHOST_CREATED = 1, 533 SHOST_RUNNING, 534 SHOST_CANCEL, 535 SHOST_DEL, 536 SHOST_RECOVERY, 537 SHOST_CANCEL_RECOVERY, 538 SHOST_DEL_RECOVERY, 539 }; 540 541 struct Scsi_Host { 542 /* 543 * __devices is protected by the host_lock, but you should 544 * usually use scsi_device_lookup / shost_for_each_device 545 * to access it and don't care about locking yourself. 546 * In the rare case of being in irq context you can use 547 * their __ prefixed variants with the lock held. NEVER 548 * access this list directly from a driver. 549 */ 550 struct list_head __devices; 551 struct list_head __targets; 552 553 struct list_head starved_list; 554 555 spinlock_t default_lock; 556 spinlock_t *host_lock; 557 558 struct mutex scan_mutex;/* serialize scanning activity */ 559 560 struct list_head eh_abort_list; 561 struct list_head eh_cmd_q; 562 struct task_struct * ehandler; /* Error recovery thread. */ 563 struct completion * eh_action; /* Wait for specific actions on the 564 host. */ 565 wait_queue_head_t host_wait; 566 const struct scsi_host_template *hostt; 567 struct scsi_transport_template *transportt; 568 569 struct kref tagset_refcnt; 570 struct completion tagset_freed; 571 /* Area to keep a shared tag map */ 572 struct blk_mq_tag_set tag_set; 573 574 atomic_t host_blocked; 575 576 unsigned int host_failed; /* commands that failed. 577 protected by host_lock */ 578 unsigned int host_eh_scheduled; /* EH scheduled without command */ 579 580 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 581 582 /* next two fields are used to bound the time spent in error handling */ 583 int eh_deadline; 584 unsigned long last_reset; 585 586 587 /* 588 * These three parameters can be used to allow for wide scsi, 589 * and for host adapters that support multiple busses 590 * The last two should be set to 1 more than the actual max id 591 * or lun (e.g. 8 for SCSI parallel systems). 592 */ 593 unsigned int max_channel; 594 unsigned int max_id; 595 u64 max_lun; 596 597 /* 598 * This is a unique identifier that must be assigned so that we 599 * have some way of identifying each detected host adapter properly 600 * and uniquely. For hosts that do not support more than one card 601 * in the system at one time, this does not need to be set. It is 602 * initialized to 0 in scsi_register. 603 */ 604 unsigned int unique_id; 605 606 /* 607 * The maximum length of SCSI commands that this host can accept. 608 * Probably 12 for most host adapters, but could be 16 for others. 609 * or 260 if the driver supports variable length cdbs. 610 * For drivers that don't set this field, a value of 12 is 611 * assumed. 612 */ 613 unsigned short max_cmd_len; 614 615 int this_id; 616 int can_queue; 617 short cmd_per_lun; 618 short unsigned int sg_tablesize; 619 short unsigned int sg_prot_tablesize; 620 unsigned int max_sectors; 621 unsigned int opt_sectors; 622 unsigned int max_segment_size; 623 unsigned int dma_alignment; 624 unsigned long dma_boundary; 625 unsigned long virt_boundary_mask; 626 /* 627 * In scsi-mq mode, the number of hardware queues supported by the LLD. 628 * 629 * Note: it is assumed that each hardware queue has a queue depth of 630 * can_queue. In other words, the total queue depth per host 631 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 632 * the total queue depth is can_queue. 633 */ 634 unsigned nr_hw_queues; 635 unsigned nr_maps; 636 unsigned active_mode:2; 637 638 /* 639 * Host has requested that no further requests come through for the 640 * time being. 641 */ 642 unsigned host_self_blocked:1; 643 644 /* 645 * Host uses correct SCSI ordering not PC ordering. The bit is 646 * set for the minority of drivers whose authors actually read 647 * the spec ;). 648 */ 649 unsigned reverse_ordering:1; 650 651 /* Task mgmt function in progress */ 652 unsigned tmf_in_progress:1; 653 654 /* Asynchronous scan in progress */ 655 unsigned async_scan:1; 656 657 /* Don't resume host in EH */ 658 unsigned eh_noresume:1; 659 660 /* The controller does not support WRITE SAME */ 661 unsigned no_write_same:1; 662 663 /* True if the host uses host-wide tagspace */ 664 unsigned host_tagset:1; 665 666 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 667 unsigned queuecommand_may_block:1; 668 669 /* Host responded with short (<36 bytes) INQUIRY result */ 670 unsigned short_inquiry:1; 671 672 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 673 unsigned no_scsi2_lun_in_cdb:1; 674 675 unsigned no_highmem:1; 676 677 /* 678 * Optional work queue to be utilized by the transport 679 */ 680 char work_q_name[20]; 681 struct workqueue_struct *work_q; 682 683 /* 684 * Task management function work queue 685 */ 686 struct workqueue_struct *tmf_work_q; 687 688 /* 689 * Value host_blocked counts down from 690 */ 691 unsigned int max_host_blocked; 692 693 /* Protection Information */ 694 unsigned int prot_capabilities; 695 unsigned char prot_guard_type; 696 697 /* legacy crap */ 698 unsigned long base; 699 unsigned long io_port; 700 unsigned char n_io_port; 701 unsigned char dma_channel; 702 unsigned int irq; 703 704 705 enum scsi_host_state shost_state; 706 707 /* ldm bits */ 708 struct device shost_gendev, shost_dev; 709 710 /* 711 * Points to the transport data (if any) which is allocated 712 * separately 713 */ 714 void *shost_data; 715 716 /* 717 * Points to the physical bus device we'd use to do DMA 718 * Needed just in case we have virtual hosts. 719 */ 720 struct device *dma_dev; 721 722 /* Delay for runtime autosuspend */ 723 int rpm_autosuspend_delay; 724 725 /* 726 * We should ensure that this is aligned, both for better performance 727 * and also because some compilers (m68k) don't automatically force 728 * alignment to a long boundary. 729 */ 730 unsigned long hostdata[] /* Used for storage of host specific stuff */ 731 __attribute__ ((aligned (sizeof(unsigned long)))); 732 }; 733 734 #define class_to_shost(d) \ 735 container_of(d, struct Scsi_Host, shost_dev) 736 737 #define shost_printk(prefix, shost, fmt, a...) \ 738 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 739 740 static inline void *shost_priv(struct Scsi_Host *shost) 741 { 742 return (void *)shost->hostdata; 743 } 744 745 int scsi_is_host_device(const struct device *); 746 747 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 748 { 749 while (!scsi_is_host_device(dev)) { 750 if (!dev->parent) 751 return NULL; 752 dev = dev->parent; 753 } 754 return container_of(dev, struct Scsi_Host, shost_gendev); 755 } 756 757 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 758 { 759 return shost->shost_state == SHOST_RECOVERY || 760 shost->shost_state == SHOST_CANCEL_RECOVERY || 761 shost->shost_state == SHOST_DEL_RECOVERY || 762 shost->tmf_in_progress; 763 } 764 765 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 766 extern void scsi_flush_work(struct Scsi_Host *); 767 768 extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int); 769 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 770 struct device *, 771 struct device *); 772 #if defined(CONFIG_SCSI_PROC_FS) 773 struct proc_dir_entry * 774 scsi_template_proc_dir(const struct scsi_host_template *sht); 775 #else 776 #define scsi_template_proc_dir(sht) NULL 777 #endif 778 extern void scsi_scan_host(struct Scsi_Host *); 779 extern int scsi_resume_device(struct scsi_device *sdev); 780 extern int scsi_rescan_device(struct scsi_device *sdev); 781 extern void scsi_remove_host(struct Scsi_Host *); 782 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 783 extern int scsi_host_busy(struct Scsi_Host *shost); 784 extern void scsi_host_put(struct Scsi_Host *t); 785 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum); 786 extern const char *scsi_host_state_name(enum scsi_host_state); 787 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 788 enum scsi_host_status status); 789 790 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 791 struct device *dev) 792 { 793 return scsi_add_host_with_dma(host, dev, dev); 794 } 795 796 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 797 { 798 return shost->shost_gendev.parent; 799 } 800 801 /** 802 * scsi_host_scan_allowed - Is scanning of this host allowed 803 * @shost: Pointer to Scsi_Host. 804 **/ 805 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 806 { 807 return shost->shost_state == SHOST_RUNNING || 808 shost->shost_state == SHOST_RECOVERY; 809 } 810 811 extern void scsi_unblock_requests(struct Scsi_Host *); 812 extern void scsi_block_requests(struct Scsi_Host *); 813 extern int scsi_host_block(struct Scsi_Host *shost); 814 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 815 816 void scsi_host_busy_iter(struct Scsi_Host *, 817 bool (*fn)(struct scsi_cmnd *, void *), void *priv); 818 819 struct class_container; 820 821 /* 822 * DIF defines the exchange of protection information between 823 * initiator and SBC block device. 824 * 825 * DIX defines the exchange of protection information between OS and 826 * initiator. 827 */ 828 enum scsi_host_prot_capabilities { 829 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 830 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 831 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 832 833 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 834 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 835 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 836 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 837 }; 838 839 /* 840 * SCSI hosts which support the Data Integrity Extensions must 841 * indicate their capabilities by setting the prot_capabilities using 842 * this call. 843 */ 844 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 845 { 846 shost->prot_capabilities = mask; 847 } 848 849 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 850 { 851 return shost->prot_capabilities; 852 } 853 854 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 855 { 856 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 857 } 858 859 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 860 { 861 static unsigned char cap[] = { 0, 862 SHOST_DIF_TYPE1_PROTECTION, 863 SHOST_DIF_TYPE2_PROTECTION, 864 SHOST_DIF_TYPE3_PROTECTION }; 865 866 if (target_type >= ARRAY_SIZE(cap)) 867 return 0; 868 869 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 870 } 871 872 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 873 { 874 #if defined(CONFIG_BLK_DEV_INTEGRITY) 875 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 876 SHOST_DIX_TYPE1_PROTECTION, 877 SHOST_DIX_TYPE2_PROTECTION, 878 SHOST_DIX_TYPE3_PROTECTION }; 879 880 if (target_type >= ARRAY_SIZE(cap)) 881 return 0; 882 883 return shost->prot_capabilities & cap[target_type]; 884 #endif 885 return 0; 886 } 887 888 /* 889 * All DIX-capable initiators must support the T10-mandated CRC 890 * checksum. Controllers can optionally implement the IP checksum 891 * scheme which has much lower impact on system performance. Note 892 * that the main rationale for the checksum is to match integrity 893 * metadata with data. Detecting bit errors are a job for ECC memory 894 * and buses. 895 */ 896 897 enum scsi_host_guard_type { 898 SHOST_DIX_GUARD_CRC = 1 << 0, 899 SHOST_DIX_GUARD_IP = 1 << 1, 900 }; 901 902 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 903 { 904 shost->prot_guard_type = type; 905 } 906 907 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 908 { 909 return shost->prot_guard_type; 910 } 911 912 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 913 914 #endif /* _SCSI_SCSI_HOST_H */ 915