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 * Queue a reserved command (BLK_MQ_REQ_RESERVED). The .queuecommand() 91 * documentation also applies to the .queue_reserved_command() callback. 92 */ 93 int (*queue_reserved_command)(struct Scsi_Host *, struct scsi_cmnd *); 94 95 /* 96 * The commit_rqs function is used to trigger a hardware 97 * doorbell after some requests have been queued with 98 * queuecommand, when an error is encountered before sending 99 * the request with SCMD_LAST set. 100 * 101 * STATUS: OPTIONAL 102 */ 103 void (*commit_rqs)(struct Scsi_Host *, u16); 104 105 struct module *module; 106 const char *name; 107 108 /* 109 * The info function will return whatever useful information the 110 * developer sees fit. If not provided, then the name field will 111 * be used instead. 112 * 113 * Status: OPTIONAL 114 */ 115 const char *(*info)(struct Scsi_Host *); 116 117 /* 118 * Ioctl interface 119 * 120 * Status: OPTIONAL 121 */ 122 int (*ioctl)(struct scsi_device *dev, unsigned int cmd, 123 void __user *arg); 124 125 126 #ifdef CONFIG_COMPAT 127 /* 128 * Compat handler. Handle 32bit ABI. 129 * When unknown ioctl is passed return -ENOIOCTLCMD. 130 * 131 * Status: OPTIONAL 132 */ 133 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, 134 void __user *arg); 135 #endif 136 137 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 138 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 139 140 /* 141 * This is an error handling strategy routine. You don't need to 142 * define one of these if you don't want to - there is a default 143 * routine that is present that should work in most cases. For those 144 * driver authors that have the inclination and ability to write their 145 * own strategy routine, this is where it is specified. Note - the 146 * strategy routine is *ALWAYS* run in the context of the kernel eh 147 * thread. Thus you are guaranteed to *NOT* be in an interrupt 148 * handler when you execute this, and you are also guaranteed to 149 * *NOT* have any other commands being queued while you are in the 150 * strategy routine. When you return from this function, operations 151 * return to normal. 152 * 153 * See scsi_error.c scsi_unjam_host for additional comments about 154 * what this function should and should not be attempting to do. 155 * 156 * Status: REQUIRED (at least one of them) 157 */ 158 int (* eh_abort_handler)(struct scsi_cmnd *); 159 int (* eh_device_reset_handler)(struct scsi_cmnd *); 160 int (* eh_target_reset_handler)(struct scsi_cmnd *); 161 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 162 int (* eh_host_reset_handler)(struct scsi_cmnd *); 163 164 /* 165 * Before the mid layer attempts to scan for a new device where none 166 * currently exists, it will call this entry in your driver. Should 167 * your driver need to allocate any structs or perform any other init 168 * items in order to send commands to a currently unused target/lun 169 * combo, then this is where you can perform those allocations. This 170 * is specifically so that drivers won't have to perform any kind of 171 * "is this a new device" checks in their queuecommand routine, 172 * thereby making the hot path a bit quicker. 173 * 174 * Return values: 0 on success, non-0 on failure 175 * 176 * Deallocation: If we didn't find any devices at this ID, you will 177 * get an immediate call to sdev_destroy(). If we find something 178 * here then you will get a call to sdev_configure(), then the 179 * device will be used for however long it is kept around, then when 180 * the device is removed from the system (or * possibly at reboot 181 * time), you will then get a call to sdev_destroy(). This is 182 * assuming you implement sdev_configure and sdev_destroy. 183 * However, if you allocate memory and hang it off the device struct, 184 * then you must implement the sdev_destroy() routine at a minimum 185 * in order to avoid leaking memory 186 * each time a device is tore down. 187 * 188 * Status: OPTIONAL 189 */ 190 int (* sdev_init)(struct scsi_device *); 191 192 /* 193 * Once the device has responded to an INQUIRY and we know the 194 * device is online, we call into the low level driver with the 195 * struct scsi_device *. If the low level device driver implements 196 * this function, it *must* perform the task of setting the queue 197 * depth on the device. All other tasks are optional and depend 198 * on what the driver supports and various implementation details. 199 * 200 * Things currently recommended to be handled at this time include: 201 * 202 * 1. Setting the device queue depth. Proper setting of this is 203 * described in the comments for scsi_change_queue_depth. 204 * 2. Determining if the device supports the various synchronous 205 * negotiation protocols. The device struct will already have 206 * responded to INQUIRY and the results of the standard items 207 * will have been shoved into the various device flag bits, eg. 208 * device->sdtr will be true if the device supports SDTR messages. 209 * 3. Allocating command structs that the device will need. 210 * 4. Setting the default timeout on this device (if needed). 211 * 5. Anything else the low level driver might want to do on a device 212 * specific setup basis... 213 * 6. Return 0 on success, non-0 on error. The device will be marked 214 * as offline on error so that no access will occur. If you return 215 * non-0, your sdev_destroy routine will never get called for this 216 * device, so don't leave any loose memory hanging around, clean 217 * up after yourself before returning non-0 218 * 219 * Status: OPTIONAL 220 */ 221 int (* sdev_configure)(struct scsi_device *, struct queue_limits *lim); 222 223 /* 224 * Immediately prior to deallocating the device and after all activity 225 * has ceased the mid layer calls this point so that the low level 226 * driver may completely detach itself from the scsi device and vice 227 * versa. The low level driver is responsible for freeing any memory 228 * it allocated in the sdev_init or sdev_configure calls. 229 * 230 * Status: OPTIONAL 231 */ 232 void (* sdev_destroy)(struct scsi_device *); 233 234 /* 235 * Before the mid layer attempts to scan for a new device attached 236 * to a target where no target currently exists, it will call this 237 * entry in your driver. Should your driver need to allocate any 238 * structs or perform any other init items in order to send commands 239 * to a currently unused target, then this is where you can perform 240 * those allocations. 241 * 242 * Return values: 0 on success, non-0 on failure 243 * 244 * Status: OPTIONAL 245 */ 246 int (* target_alloc)(struct scsi_target *); 247 248 /* 249 * Immediately prior to deallocating the target structure, and 250 * after all activity to attached scsi devices has ceased, the 251 * midlayer calls this point so that the driver may deallocate 252 * and terminate any references to the target. 253 * 254 * Note: This callback is called with the host lock held and hence 255 * must not sleep. 256 * 257 * Status: OPTIONAL 258 */ 259 void (* target_destroy)(struct scsi_target *); 260 261 /* 262 * If a host has the ability to discover targets on its own instead 263 * of scanning the entire bus, it can fill in this function and 264 * call scsi_scan_host(). This function will be called periodically 265 * until it returns 1 with the scsi_host and the elapsed time of 266 * the scan in jiffies. 267 * 268 * Status: OPTIONAL 269 */ 270 int (* scan_finished)(struct Scsi_Host *, unsigned long); 271 272 /* 273 * If the host wants to be called before the scan starts, but 274 * after the midlayer has set up ready for the scan, it can fill 275 * in this function. 276 * 277 * Status: OPTIONAL 278 */ 279 void (* scan_start)(struct Scsi_Host *); 280 281 /* 282 * Fill in this function to allow the queue depth of this host 283 * to be changeable (on a per device basis). Returns either 284 * the current queue depth setting (may be different from what 285 * was passed in) or an error. An error should only be 286 * returned if the requested depth is legal but the driver was 287 * unable to set it. If the requested depth is illegal, the 288 * driver should set and return the closest legal queue depth. 289 * 290 * Status: OPTIONAL 291 */ 292 int (* change_queue_depth)(struct scsi_device *, int); 293 294 /* 295 * This functions lets the driver expose the queue mapping 296 * to the block layer. 297 * 298 * Status: OPTIONAL 299 */ 300 void (* map_queues)(struct Scsi_Host *shost); 301 302 /* 303 * SCSI interface of blk_poll - poll for IO completions. 304 * Only applicable if SCSI LLD exposes multiple h/w queues. 305 * 306 * Return value: Number of completed entries found. 307 * 308 * Status: OPTIONAL 309 */ 310 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num); 311 312 /* 313 * Check if scatterlists need to be padded for DMA draining. 314 * 315 * Status: OPTIONAL 316 */ 317 bool (* dma_need_drain)(struct request *rq); 318 319 /* 320 * This function determines the BIOS parameters for a given 321 * harddisk. These tend to be numbers that are made up by 322 * the host adapter. Parameters: 323 * size, device, list (heads, sectors, cylinders) 324 * 325 * Status: OPTIONAL 326 */ 327 int (* bios_param)(struct scsi_device *, struct gendisk *, 328 sector_t, int []); 329 330 /* 331 * This function is called when one or more partitions on the 332 * device reach beyond the end of the device. 333 * 334 * Status: OPTIONAL 335 */ 336 void (*unlock_native_capacity)(struct scsi_device *); 337 338 /* 339 * Can be used to export driver statistics and other infos to the 340 * world outside the kernel ie. userspace and it also provides an 341 * interface to feed the driver with information. 342 * 343 * Status: OBSOLETE 344 */ 345 int (*show_info)(struct seq_file *, struct Scsi_Host *); 346 int (*write_info)(struct Scsi_Host *, char *, int); 347 348 /* 349 * This is an optional routine that allows the transport to become 350 * involved when a scsi io timer fires. The return value tells the 351 * timer routine how to finish the io timeout handling. 352 * 353 * Status: OPTIONAL 354 */ 355 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *); 356 /* 357 * Optional routine that allows the transport to decide if a cmd 358 * is retryable. Return true if the transport is in a state the 359 * cmd should be retried on. 360 */ 361 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 362 363 /* This is an optional routine that allows transport to initiate 364 * LLD adapter or firmware reset using sysfs attribute. 365 * 366 * Return values: 0 on success, -ve value on failure. 367 * 368 * Status: OPTIONAL 369 */ 370 371 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 372 #define SCSI_ADAPTER_RESET 1 373 #define SCSI_FIRMWARE_RESET 2 374 375 376 /* 377 * Name of proc directory 378 */ 379 const char *proc_name; 380 381 /* 382 * This determines if we will use a non-interrupt driven 383 * or an interrupt driven scheme. It is set to the maximum number 384 * of simultaneous commands a single hw queue in HBA will accept 385 * excluding internal commands. 386 */ 387 int can_queue; 388 389 /* 390 * This determines how many commands the HBA will set aside 391 * for internal commands. This number will be added to 392 * @can_queue to calculate the maximum number of simultaneous 393 * commands sent to the host. 394 */ 395 int nr_reserved_cmds; 396 397 /* 398 * In many instances, especially where disconnect / reconnect are 399 * supported, our host also has an ID on the SCSI bus. If this is 400 * the case, then it must be reserved. Please set this_id to -1 if 401 * your setup is in single initiator mode, and the host lacks an 402 * ID. 403 */ 404 int this_id; 405 406 /* 407 * This determines the degree to which the host adapter is capable 408 * of scatter-gather. 409 */ 410 unsigned short sg_tablesize; 411 unsigned short sg_prot_tablesize; 412 413 /* 414 * Set this if the host adapter has limitations beside segment count. 415 */ 416 unsigned int max_sectors; 417 418 /* 419 * Maximum size in bytes of a single segment. 420 */ 421 unsigned int max_segment_size; 422 423 unsigned int dma_alignment; 424 425 /* 426 * DMA scatter gather segment boundary limit. A segment crossing this 427 * boundary will be split in two. 428 */ 429 unsigned long dma_boundary; 430 431 unsigned long virt_boundary_mask; 432 433 /* 434 * This specifies "machine infinity" for host templates which don't 435 * limit the transfer size. Note this limit represents an absolute 436 * maximum, and may be over the transfer limits allowed for 437 * individual devices (e.g. 256 for SCSI-1). 438 */ 439 #define SCSI_DEFAULT_MAX_SECTORS 1024 440 441 /* 442 * True if this host adapter can make good use of linked commands. 443 * This will allow more than one command to be queued to a given 444 * unit on a given host. Set this to the maximum number of command 445 * blocks to be provided for each device. Set this to 1 for one 446 * command block per lun, 2 for two, etc. Do not set this to 0. 447 * You should make sure that the host adapter will do the right thing 448 * before you try setting this above 1. 449 */ 450 short cmd_per_lun; 451 452 /* 453 * Allocate tags starting from last allocated tag. 454 */ 455 bool tag_alloc_policy_rr : 1; 456 457 /* 458 * Track QUEUE_FULL events and reduce queue depth on demand. 459 */ 460 unsigned track_queue_depth:1; 461 462 /* 463 * This specifies the mode that a LLD supports. 464 */ 465 unsigned supported_mode:2; 466 467 /* 468 * True for emulated SCSI host adapters (e.g. ATAPI). 469 */ 470 unsigned emulated:1; 471 472 /* 473 * True if the low-level driver performs its own reset-settle delays. 474 */ 475 unsigned skip_settle_delay:1; 476 477 /* True if the controller does not support WRITE SAME */ 478 unsigned no_write_same:1; 479 480 /* True if the host uses host-wide tagspace */ 481 unsigned host_tagset:1; 482 483 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 484 unsigned queuecommand_may_block:1; 485 486 /* 487 * Countdown for host blocking with no commands outstanding. 488 */ 489 unsigned int max_host_blocked; 490 491 /* 492 * Default value for the blocking. If the queue is empty, 493 * host_blocked counts down in the request_fn until it restarts 494 * host operations as zero is reached. 495 * 496 * FIXME: This should probably be a value in the template 497 */ 498 #define SCSI_DEFAULT_HOST_BLOCKED 7 499 500 /* 501 * Pointer to the SCSI host sysfs attribute groups, NULL terminated. 502 */ 503 const struct attribute_group **shost_groups; 504 505 /* 506 * Pointer to the SCSI device attribute groups for this host, 507 * NULL terminated. 508 */ 509 const struct attribute_group **sdev_groups; 510 511 /* 512 * Vendor Identifier associated with the host 513 * 514 * Note: When specifying vendor_id, be sure to read the 515 * Vendor Type and ID formatting requirements specified in 516 * scsi_netlink.h 517 */ 518 u64 vendor_id; 519 }; 520 521 /* 522 * Temporary #define for host lock push down. Can be removed when all 523 * drivers have been updated to take advantage of unlocked 524 * queuecommand. 525 * 526 */ 527 #define DEF_SCSI_QCMD(func_name) \ 528 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \ 529 { \ 530 unsigned long irq_flags; \ 531 int rc; \ 532 spin_lock_irqsave(shost->host_lock, irq_flags); \ 533 rc = func_name##_lck(cmd); \ 534 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 535 return rc; \ 536 } 537 538 539 /* 540 * shost state: If you alter this, you also need to alter scsi_sysfs.c 541 * (for the ascii descriptions) and the state model enforcer: 542 * scsi_host_set_state() 543 */ 544 enum scsi_host_state { 545 SHOST_CREATED = 1, 546 SHOST_RUNNING, 547 SHOST_CANCEL, 548 SHOST_DEL, 549 SHOST_RECOVERY, 550 SHOST_CANCEL_RECOVERY, 551 SHOST_DEL_RECOVERY, 552 }; 553 554 struct Scsi_Host { 555 /* 556 * __devices is protected by the host_lock, but you should 557 * usually use scsi_device_lookup / shost_for_each_device 558 * to access it and don't care about locking yourself. 559 * In the rare case of being in irq context you can use 560 * their __ prefixed variants with the lock held. NEVER 561 * access this list directly from a driver. 562 */ 563 struct list_head __devices; 564 struct list_head __targets; 565 566 struct list_head starved_list; 567 568 spinlock_t default_lock; 569 spinlock_t *host_lock; 570 571 struct mutex scan_mutex;/* serialize scanning activity */ 572 573 struct list_head eh_abort_list; 574 struct list_head eh_cmd_q; 575 struct task_struct * ehandler; /* Error recovery thread. */ 576 struct completion * eh_action; /* Wait for specific actions on the 577 host. */ 578 wait_queue_head_t host_wait; 579 const struct scsi_host_template *hostt; 580 struct scsi_transport_template *transportt; 581 582 struct kref tagset_refcnt; 583 struct completion tagset_freed; 584 /* Area to keep a shared tag map */ 585 struct blk_mq_tag_set tag_set; 586 587 atomic_t host_blocked; 588 589 unsigned int host_failed; /* commands that failed. 590 protected by host_lock */ 591 unsigned int host_eh_scheduled; /* EH scheduled without command */ 592 593 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 594 595 /* next two fields are used to bound the time spent in error handling */ 596 int eh_deadline; 597 unsigned long last_reset; 598 599 600 /* 601 * These three parameters can be used to allow for wide scsi, 602 * and for host adapters that support multiple busses 603 * The last two should be set to 1 more than the actual max id 604 * or lun (e.g. 8 for SCSI parallel systems). 605 */ 606 unsigned int max_channel; 607 unsigned int max_id; 608 u64 max_lun; 609 610 /* 611 * This is a unique identifier that must be assigned so that we 612 * have some way of identifying each detected host adapter properly 613 * and uniquely. For hosts that do not support more than one card 614 * in the system at one time, this does not need to be set. It is 615 * initialized to 0 in scsi_host_alloc. 616 */ 617 unsigned int unique_id; 618 619 /* 620 * The maximum length of SCSI commands that this host can accept. 621 * Probably 12 for most host adapters, but could be 16 for others. 622 * or 260 if the driver supports variable length cdbs. 623 * For drivers that don't set this field, a value of 12 is 624 * assumed. 625 */ 626 unsigned short max_cmd_len; 627 628 int this_id; 629 630 /* 631 * Number of commands this host can handle at the same time. 632 * This excludes reserved commands as specified by nr_reserved_cmds. 633 */ 634 int can_queue; 635 /* 636 * Number of reserved commands to allocate, if any. 637 */ 638 unsigned int nr_reserved_cmds; 639 640 short cmd_per_lun; 641 short unsigned int sg_tablesize; 642 short unsigned int sg_prot_tablesize; 643 unsigned int max_sectors; 644 unsigned int opt_sectors; 645 unsigned int max_segment_size; 646 unsigned int dma_alignment; 647 unsigned long dma_boundary; 648 unsigned long virt_boundary_mask; 649 /* 650 * In scsi-mq mode, the number of hardware queues supported by the LLD. 651 * 652 * Note: it is assumed that each hardware queue has a queue depth of 653 * can_queue. In other words, the total queue depth per host 654 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 655 * the total queue depth is can_queue. 656 */ 657 unsigned nr_hw_queues; 658 unsigned nr_maps; 659 unsigned active_mode:2; 660 661 /* 662 * Host has requested that no further requests come through for the 663 * time being. 664 */ 665 unsigned host_self_blocked:1; 666 667 /* 668 * Host uses correct SCSI ordering not PC ordering. The bit is 669 * set for the minority of drivers whose authors actually read 670 * the spec ;). 671 */ 672 unsigned reverse_ordering:1; 673 674 /* Task mgmt function in progress */ 675 unsigned tmf_in_progress:1; 676 677 /* Asynchronous scan in progress */ 678 unsigned async_scan:1; 679 680 /* Don't resume host in EH */ 681 unsigned eh_noresume:1; 682 683 /* The controller does not support WRITE SAME */ 684 unsigned no_write_same:1; 685 686 /* True if the host uses host-wide tagspace */ 687 unsigned host_tagset:1; 688 689 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 690 unsigned queuecommand_may_block:1; 691 692 /* Host responded with short (<36 bytes) INQUIRY result */ 693 unsigned short_inquiry:1; 694 695 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 696 unsigned no_scsi2_lun_in_cdb:1; 697 698 /* 699 * Optional work queue to be utilized by the transport 700 */ 701 struct workqueue_struct *work_q; 702 703 /* 704 * Task management function work queue 705 */ 706 struct workqueue_struct *tmf_work_q; 707 708 /* 709 * Value host_blocked counts down from 710 */ 711 unsigned int max_host_blocked; 712 713 /* Protection Information */ 714 unsigned int prot_capabilities; 715 unsigned char prot_guard_type; 716 717 /* legacy crap */ 718 unsigned long base; 719 unsigned long io_port; 720 unsigned char n_io_port; 721 unsigned char dma_channel; 722 unsigned int irq; 723 724 725 enum scsi_host_state shost_state; 726 727 /* ldm bits */ 728 struct device shost_gendev, shost_dev; 729 730 /* 731 * A SCSI device structure used for sending internal commands to the 732 * HBA. There is no corresponding logical unit inside the SCSI device. 733 */ 734 struct scsi_device *pseudo_sdev; 735 736 /* 737 * Points to the transport data (if any) which is allocated 738 * separately 739 */ 740 void *shost_data; 741 742 /* 743 * Points to the physical bus device we'd use to do DMA 744 * Needed just in case we have virtual hosts. 745 */ 746 struct device *dma_dev; 747 748 /* Delay for runtime autosuspend */ 749 int rpm_autosuspend_delay; 750 751 /* 752 * We should ensure that this is aligned, both for better performance 753 * and also because some compilers (m68k) don't automatically force 754 * alignment to a long boundary. 755 */ 756 unsigned long hostdata[] /* Used for storage of host specific stuff */ 757 __attribute__ ((aligned (sizeof(unsigned long)))); 758 }; 759 760 #define class_to_shost(d) \ 761 container_of(d, struct Scsi_Host, shost_dev) 762 763 #define shost_printk(prefix, shost, fmt, a...) \ 764 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 765 766 static inline void *shost_priv(struct Scsi_Host *shost) 767 { 768 return (void *)shost->hostdata; 769 } 770 771 int scsi_is_host_device(const struct device *); 772 773 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 774 { 775 while (!scsi_is_host_device(dev)) { 776 if (!dev->parent) 777 return NULL; 778 dev = dev->parent; 779 } 780 return container_of(dev, struct Scsi_Host, shost_gendev); 781 } 782 783 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 784 { 785 return shost->shost_state == SHOST_RECOVERY || 786 shost->shost_state == SHOST_CANCEL_RECOVERY || 787 shost->shost_state == SHOST_DEL_RECOVERY || 788 shost->tmf_in_progress; 789 } 790 791 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 792 extern void scsi_flush_work(struct Scsi_Host *); 793 794 extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int); 795 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 796 struct device *, 797 struct device *); 798 #if defined(CONFIG_SCSI_PROC_FS) 799 struct proc_dir_entry * 800 scsi_template_proc_dir(const struct scsi_host_template *sht); 801 #else 802 #define scsi_template_proc_dir(sht) NULL 803 #endif 804 extern void scsi_scan_host(struct Scsi_Host *); 805 extern int scsi_resume_device(struct scsi_device *sdev); 806 extern int scsi_rescan_device(struct scsi_device *sdev); 807 extern void scsi_remove_host(struct Scsi_Host *); 808 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 809 extern int scsi_host_busy(struct Scsi_Host *shost); 810 extern void scsi_host_put(struct Scsi_Host *t); 811 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum); 812 extern const char *scsi_host_state_name(enum scsi_host_state); 813 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 814 enum scsi_host_status status); 815 816 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 817 struct device *dev) 818 { 819 return scsi_add_host_with_dma(host, dev, dev); 820 } 821 822 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 823 { 824 return shost->shost_gendev.parent; 825 } 826 827 /** 828 * scsi_host_scan_allowed - Is scanning of this host allowed 829 * @shost: Pointer to Scsi_Host. 830 **/ 831 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 832 { 833 return shost->shost_state == SHOST_RUNNING || 834 shost->shost_state == SHOST_RECOVERY; 835 } 836 837 extern void scsi_unblock_requests(struct Scsi_Host *); 838 extern void scsi_block_requests(struct Scsi_Host *); 839 extern int scsi_host_block(struct Scsi_Host *shost); 840 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 841 842 void scsi_host_busy_iter(struct Scsi_Host *, 843 bool (*fn)(struct scsi_cmnd *, void *), void *priv); 844 845 struct class_container; 846 847 /* 848 * DIF defines the exchange of protection information between 849 * initiator and SBC block device. 850 * 851 * DIX defines the exchange of protection information between OS and 852 * initiator. 853 */ 854 enum scsi_host_prot_capabilities { 855 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 856 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 857 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 858 859 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 860 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 861 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 862 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 863 }; 864 865 /* 866 * SCSI hosts which support the Data Integrity Extensions must 867 * indicate their capabilities by setting the prot_capabilities using 868 * this call. 869 */ 870 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 871 { 872 shost->prot_capabilities = mask; 873 } 874 875 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 876 { 877 return shost->prot_capabilities; 878 } 879 880 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 881 { 882 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 883 } 884 885 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 886 { 887 static unsigned char cap[] = { 0, 888 SHOST_DIF_TYPE1_PROTECTION, 889 SHOST_DIF_TYPE2_PROTECTION, 890 SHOST_DIF_TYPE3_PROTECTION }; 891 892 if (target_type >= ARRAY_SIZE(cap)) 893 return 0; 894 895 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 896 } 897 898 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 899 { 900 #if defined(CONFIG_BLK_DEV_INTEGRITY) 901 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 902 SHOST_DIX_TYPE1_PROTECTION, 903 SHOST_DIX_TYPE2_PROTECTION, 904 SHOST_DIX_TYPE3_PROTECTION }; 905 906 if (target_type >= ARRAY_SIZE(cap)) 907 return 0; 908 909 return shost->prot_capabilities & cap[target_type]; 910 #endif 911 return 0; 912 } 913 914 /* 915 * All DIX-capable initiators must support the T10-mandated CRC 916 * checksum. Controllers can optionally implement the IP checksum 917 * scheme which has much lower impact on system performance. Note 918 * that the main rationale for the checksum is to match integrity 919 * metadata with data. Detecting bit errors are a job for ECC memory 920 * and buses. 921 */ 922 923 enum scsi_host_guard_type { 924 SHOST_DIX_GUARD_CRC = 1 << 0, 925 SHOST_DIX_GUARD_IP = 1 << 1, 926 }; 927 928 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 929 { 930 shost->prot_guard_type = type; 931 } 932 933 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 934 { 935 return shost->prot_guard_type; 936 } 937 938 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 939 940 #endif /* _SCSI_SCSI_HOST_H */ 941