1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _SCSI_SCSI_HOST_H 3 #define _SCSI_SCSI_HOST_H 4 5 #include <linux/cleanup.h> 6 #include <linux/device.h> 7 #include <linux/list.h> 8 #include <linux/types.h> 9 #include <linux/workqueue.h> 10 #include <linux/mutex.h> 11 #include <linux/seq_file.h> 12 #include <linux/blk-mq.h> 13 #include <scsi/scsi.h> 14 15 struct block_device; 16 struct completion; 17 struct module; 18 struct scsi_cmnd; 19 struct scsi_device; 20 struct scsi_target; 21 struct Scsi_Host; 22 struct scsi_transport_template; 23 24 25 #define SG_ALL SG_CHUNK_SIZE 26 27 #define MODE_UNKNOWN 0x00 28 #define MODE_INITIATOR 0x01 29 #define MODE_TARGET 0x02 30 31 /** 32 * enum scsi_timeout_action - How to handle a command that timed out. 33 * @SCSI_EH_DONE: The command has already been completed. 34 * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion. 35 * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command. 36 */ 37 enum scsi_timeout_action { 38 SCSI_EH_DONE, 39 SCSI_EH_RESET_TIMER, 40 SCSI_EH_NOT_HANDLED, 41 }; 42 43 struct scsi_host_template { 44 /* 45 * Put fields referenced in IO submission path together in 46 * same cacheline 47 */ 48 49 /* 50 * Additional per-command data allocated for the driver. 51 */ 52 unsigned int cmd_size; 53 54 /* 55 * The queuecommand function is used to queue up a scsi 56 * command block to the LLDD. When the driver finished 57 * processing the command the done callback is invoked. 58 * 59 * If queuecommand returns 0, then the driver has accepted the 60 * command. It must also push it to the HBA if the scsi_cmnd 61 * flag SCMD_LAST is set, or if the driver does not implement 62 * commit_rqs. The done() function must be called on the command 63 * when the driver has finished with it. (you may call done on the 64 * command before queuecommand returns, but in this case you 65 * *must* return 0 from queuecommand). 66 * 67 * Queuecommand may also reject the command, in which case it may 68 * not touch the command and must not call done() for it. 69 * 70 * There are two possible rejection returns: 71 * 72 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 73 * allow commands to other devices serviced by this host. 74 * 75 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 76 * host temporarily. 77 * 78 * For compatibility, any other non-zero return is treated the 79 * same as SCSI_MLQUEUE_HOST_BUSY. 80 * 81 * NOTE: "temporarily" means either until the next command for# 82 * this device/host completes, or a period of time determined by 83 * I/O pressure in the system if there are no other outstanding 84 * commands. 85 * 86 * STATUS: REQUIRED 87 */ 88 enum scsi_qc_status (*queuecommand)(struct Scsi_Host *, 89 struct scsi_cmnd *); 90 91 /* 92 * Queue a reserved command (BLK_MQ_REQ_RESERVED). The .queuecommand() 93 * documentation also applies to the .queue_reserved_command() callback. 94 */ 95 enum scsi_qc_status (*queue_reserved_command)(struct Scsi_Host *, 96 struct scsi_cmnd *); 97 98 /* 99 * The commit_rqs function is used to trigger a hardware 100 * doorbell after some requests have been queued with 101 * queuecommand, when an error is encountered before sending 102 * the request with SCMD_LAST set. 103 * 104 * STATUS: OPTIONAL 105 */ 106 void (*commit_rqs)(struct Scsi_Host *, u16); 107 108 struct module *module; 109 const char *name; 110 111 /* 112 * The info function will return whatever useful information the 113 * developer sees fit. If not provided, then the name field will 114 * be used instead. 115 * 116 * Status: OPTIONAL 117 */ 118 const char *(*info)(struct Scsi_Host *); 119 120 /* 121 * Ioctl interface 122 * 123 * Status: OPTIONAL 124 */ 125 int (*ioctl)(struct scsi_device *dev, unsigned int cmd, 126 void __user *arg); 127 128 129 #ifdef CONFIG_COMPAT 130 /* 131 * Compat handler. Handle 32bit ABI. 132 * When unknown ioctl is passed return -ENOIOCTLCMD. 133 * 134 * Status: OPTIONAL 135 */ 136 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, 137 void __user *arg); 138 #endif 139 140 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 141 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 142 143 /* 144 * This is an error handling strategy routine. You don't need to 145 * define one of these if you don't want to - there is a default 146 * routine that is present that should work in most cases. For those 147 * driver authors that have the inclination and ability to write their 148 * own strategy routine, this is where it is specified. Note - the 149 * strategy routine is *ALWAYS* run in the context of the kernel eh 150 * thread. Thus you are guaranteed to *NOT* be in an interrupt 151 * handler when you execute this, and you are also guaranteed to 152 * *NOT* have any other commands being queued while you are in the 153 * strategy routine. When you return from this function, operations 154 * return to normal. 155 * 156 * See scsi_error.c scsi_unjam_host for additional comments about 157 * what this function should and should not be attempting to do. 158 * 159 * Status: REQUIRED (at least one of them) 160 */ 161 int (* eh_abort_handler)(struct scsi_cmnd *); 162 int (* eh_device_reset_handler)(struct scsi_cmnd *); 163 int (* eh_target_reset_handler)(struct scsi_cmnd *); 164 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 165 int (* eh_host_reset_handler)(struct scsi_cmnd *); 166 167 /* 168 * Before the mid layer attempts to scan for a new device where none 169 * currently exists, it will call this entry in your driver. Should 170 * your driver need to allocate any structs or perform any other init 171 * items in order to send commands to a currently unused target/lun 172 * combo, then this is where you can perform those allocations. This 173 * is specifically so that drivers won't have to perform any kind of 174 * "is this a new device" checks in their queuecommand routine, 175 * thereby making the hot path a bit quicker. 176 * 177 * Return values: 0 on success, non-0 on failure 178 * 179 * Deallocation: If we didn't find any devices at this ID, you will 180 * get an immediate call to sdev_destroy(). If we find something 181 * here then you will get a call to sdev_configure(), then the 182 * device will be used for however long it is kept around, then when 183 * the device is removed from the system (or * possibly at reboot 184 * time), you will then get a call to sdev_destroy(). This is 185 * assuming you implement sdev_configure and sdev_destroy. 186 * However, if you allocate memory and hang it off the device struct, 187 * then you must implement the sdev_destroy() routine at a minimum 188 * in order to avoid leaking memory 189 * each time a device is tore down. 190 * 191 * Status: OPTIONAL 192 */ 193 int (* sdev_init)(struct scsi_device *); 194 195 /* 196 * Once the device has responded to an INQUIRY and we know the 197 * device is online, we call into the low level driver with the 198 * struct scsi_device *. If the low level device driver implements 199 * this function, it *must* perform the task of setting the queue 200 * depth on the device. All other tasks are optional and depend 201 * on what the driver supports and various implementation details. 202 * 203 * Things currently recommended to be handled at this time include: 204 * 205 * 1. Setting the device queue depth. Proper setting of this is 206 * described in the comments for scsi_change_queue_depth. 207 * 2. Determining if the device supports the various synchronous 208 * negotiation protocols. The device struct will already have 209 * responded to INQUIRY and the results of the standard items 210 * will have been shoved into the various device flag bits, eg. 211 * device->sdtr will be true if the device supports SDTR messages. 212 * 3. Allocating command structs that the device will need. 213 * 4. Setting the default timeout on this device (if needed). 214 * 5. Anything else the low level driver might want to do on a device 215 * specific setup basis... 216 * 6. Return 0 on success, non-0 on error. The device will be marked 217 * as offline on error so that no access will occur. If you return 218 * non-0, your sdev_destroy routine will never get called for this 219 * device, so don't leave any loose memory hanging around, clean 220 * up after yourself before returning non-0 221 * 222 * Status: OPTIONAL 223 */ 224 int (* sdev_configure)(struct scsi_device *, struct queue_limits *lim); 225 226 /* 227 * Immediately prior to deallocating the device and after all activity 228 * has ceased the mid layer calls this point so that the low level 229 * driver may completely detach itself from the scsi device and vice 230 * versa. The low level driver is responsible for freeing any memory 231 * it allocated in the sdev_init or sdev_configure calls. 232 * 233 * Status: OPTIONAL 234 */ 235 void (* sdev_destroy)(struct scsi_device *); 236 237 /* 238 * Before the mid layer attempts to scan for a new device attached 239 * to a target where no target currently exists, it will call this 240 * entry in your driver. Should your driver need to allocate any 241 * structs or perform any other init items in order to send commands 242 * to a currently unused target, then this is where you can perform 243 * those allocations. 244 * 245 * Return values: 0 on success, non-0 on failure 246 * 247 * Status: OPTIONAL 248 */ 249 int (* target_alloc)(struct scsi_target *); 250 251 /* 252 * Immediately prior to deallocating the target structure, and 253 * after all activity to attached scsi devices has ceased, the 254 * midlayer calls this point so that the driver may deallocate 255 * and terminate any references to the target. 256 * 257 * Note: This callback is called with the host lock held and hence 258 * must not sleep. 259 * 260 * Status: OPTIONAL 261 */ 262 void (* target_destroy)(struct scsi_target *); 263 264 /* 265 * If a host has the ability to discover targets on its own instead 266 * of scanning the entire bus, it can fill in this function and 267 * call scsi_scan_host(). This function will be called periodically 268 * until it returns 1 with the scsi_host and the elapsed time of 269 * the scan in jiffies. 270 * 271 * Status: OPTIONAL 272 */ 273 int (* scan_finished)(struct Scsi_Host *, unsigned long); 274 275 /* 276 * If the host wants to be called before the scan starts, but 277 * after the midlayer has set up ready for the scan, it can fill 278 * in this function. 279 * 280 * Status: OPTIONAL 281 */ 282 void (* scan_start)(struct Scsi_Host *); 283 284 /* 285 * Fill in this function to allow the queue depth of this host 286 * to be changeable (on a per device basis). Returns either 287 * the current queue depth setting (may be different from what 288 * was passed in) or an error. An error should only be 289 * returned if the requested depth is legal but the driver was 290 * unable to set it. If the requested depth is illegal, the 291 * driver should set and return the closest legal queue depth. 292 * 293 * Status: OPTIONAL 294 */ 295 int (* change_queue_depth)(struct scsi_device *, int); 296 297 /* 298 * This functions lets the driver expose the queue mapping 299 * to the block layer. 300 * 301 * Status: OPTIONAL 302 */ 303 void (* map_queues)(struct Scsi_Host *shost); 304 305 /* 306 * SCSI interface of blk_poll - poll for IO completions. 307 * Only applicable if SCSI LLD exposes multiple h/w queues. 308 * 309 * Return value: Number of completed entries found. 310 * 311 * Status: OPTIONAL 312 */ 313 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num); 314 315 /* 316 * Check if scatterlists need to be padded for DMA draining. 317 * 318 * Status: OPTIONAL 319 */ 320 bool (* dma_need_drain)(struct request *rq); 321 322 /* 323 * This function determines the BIOS parameters for a given 324 * harddisk. These tend to be numbers that are made up by 325 * the host adapter. Parameters: 326 * size, device, list (heads, sectors, cylinders) 327 * 328 * Status: OPTIONAL 329 */ 330 int (* bios_param)(struct scsi_device *, struct gendisk *, 331 sector_t, int []); 332 333 /* 334 * This function is called when one or more partitions on the 335 * device reach beyond the end of the device. 336 * 337 * Status: OPTIONAL 338 */ 339 void (*unlock_native_capacity)(struct scsi_device *); 340 341 /* 342 * Can be used to export driver statistics and other infos to the 343 * world outside the kernel ie. userspace and it also provides an 344 * interface to feed the driver with information. 345 * 346 * Status: OBSOLETE 347 */ 348 int (*show_info)(struct seq_file *, struct Scsi_Host *); 349 int (*write_info)(struct Scsi_Host *, char *, int); 350 351 /* 352 * This is an optional routine that allows the transport to become 353 * involved when a scsi io timer fires. The return value tells the 354 * timer routine how to finish the io timeout handling. 355 * 356 * Status: OPTIONAL 357 */ 358 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *); 359 /* 360 * Optional routine that allows the transport to decide if a cmd 361 * is retryable. Return true if the transport is in a state the 362 * cmd should be retried on. 363 */ 364 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 365 366 /* This is an optional routine that allows transport to initiate 367 * LLD adapter or firmware reset using sysfs attribute. 368 * 369 * Return values: 0 on success, -ve value on failure. 370 * 371 * Status: OPTIONAL 372 */ 373 374 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 375 #define SCSI_ADAPTER_RESET 1 376 #define SCSI_FIRMWARE_RESET 2 377 378 379 /* 380 * Name of proc directory 381 */ 382 const char *proc_name; 383 384 /* 385 * This determines if we will use a non-interrupt driven 386 * or an interrupt driven scheme. It is set to the maximum number 387 * of simultaneous commands a single hw queue in HBA will accept 388 * excluding internal commands. 389 */ 390 int can_queue; 391 392 /* 393 * This determines how many commands the HBA will set aside 394 * for internal commands. This number will be added to 395 * @can_queue to calculate the maximum number of simultaneous 396 * commands sent to the host. 397 */ 398 int nr_reserved_cmds; 399 400 /* 401 * In many instances, especially where disconnect / reconnect are 402 * supported, our host also has an ID on the SCSI bus. If this is 403 * the case, then it must be reserved. Please set this_id to -1 if 404 * your setup is in single initiator mode, and the host lacks an 405 * ID. 406 */ 407 int this_id; 408 409 /* 410 * This determines the degree to which the host adapter is capable 411 * of scatter-gather. 412 */ 413 unsigned short sg_tablesize; 414 unsigned short sg_prot_tablesize; 415 416 /* 417 * Set this if the host adapter has limitations beside segment count. 418 */ 419 unsigned int max_sectors; 420 421 /* 422 * Maximum size in bytes of a single segment. 423 */ 424 unsigned int max_segment_size; 425 426 unsigned int dma_alignment; 427 428 /* 429 * DMA scatter gather segment boundary limit. A segment crossing this 430 * boundary will be split in two. 431 */ 432 unsigned long dma_boundary; 433 434 unsigned long virt_boundary_mask; 435 436 /* 437 * This specifies "machine infinity" for host templates which don't 438 * limit the transfer size. Note this limit represents an absolute 439 * maximum, and may be over the transfer limits allowed for 440 * individual devices (e.g. 256 for SCSI-1). 441 */ 442 #define SCSI_DEFAULT_MAX_SECTORS 1024 443 444 /* 445 * True if this host adapter can make good use of linked commands. 446 * This will allow more than one command to be queued to a given 447 * unit on a given host. Set this to the maximum number of command 448 * blocks to be provided for each device. Set this to 1 for one 449 * command block per lun, 2 for two, etc. Do not set this to 0. 450 * You should make sure that the host adapter will do the right thing 451 * before you try setting this above 1. 452 */ 453 short cmd_per_lun; 454 455 /* 456 * Allocate tags starting from last allocated tag. 457 */ 458 bool tag_alloc_policy_rr : 1; 459 460 /* 461 * Track QUEUE_FULL events and reduce queue depth on demand. 462 */ 463 unsigned track_queue_depth:1; 464 465 /* 466 * This specifies the mode that a LLD supports. 467 */ 468 unsigned supported_mode:2; 469 470 /* 471 * True for emulated SCSI host adapters (e.g. ATAPI). 472 */ 473 unsigned emulated:1; 474 475 /* 476 * True if the low-level driver performs its own reset-settle delays. 477 */ 478 unsigned skip_settle_delay:1; 479 480 /* True if the controller does not support WRITE SAME */ 481 unsigned no_write_same:1; 482 483 /* True if the host uses host-wide tagspace */ 484 unsigned host_tagset:1; 485 486 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 487 unsigned queuecommand_may_block:1; 488 489 /* 490 * Countdown for host blocking with no commands outstanding. 491 */ 492 unsigned int max_host_blocked; 493 494 /* 495 * Default value for the blocking. If the queue is empty, 496 * host_blocked counts down in the request_fn until it restarts 497 * host operations as zero is reached. 498 * 499 * FIXME: This should probably be a value in the template 500 */ 501 #define SCSI_DEFAULT_HOST_BLOCKED 7 502 503 /* 504 * Pointer to the SCSI host sysfs attribute groups, NULL terminated. 505 */ 506 const struct attribute_group **shost_groups; 507 508 /* 509 * Pointer to the SCSI device attribute groups for this host, 510 * NULL terminated. 511 */ 512 const struct attribute_group **sdev_groups; 513 514 /* 515 * Vendor Identifier associated with the host 516 * 517 * Note: When specifying vendor_id, be sure to read the 518 * Vendor Type and ID formatting requirements specified in 519 * scsi_netlink.h 520 */ 521 u64 vendor_id; 522 }; 523 524 /* 525 * Temporary #define for host lock push down. Can be removed when all 526 * drivers have been updated to take advantage of unlocked 527 * queuecommand. 528 * 529 */ 530 #define DEF_SCSI_QCMD(func_name) \ 531 enum scsi_qc_status func_name(struct Scsi_Host *shost, \ 532 struct scsi_cmnd *cmd) \ 533 { \ 534 unsigned long irq_flags; \ 535 enum scsi_qc_status rc; \ 536 \ 537 spin_lock_irqsave(&shost->host_lock, irq_flags); \ 538 rc = func_name##_lck(cmd); \ 539 spin_unlock_irqrestore(&shost->host_lock, irq_flags); \ 540 return rc; \ 541 } 542 543 544 /* 545 * shost state: If you alter this, you also need to alter scsi_sysfs.c 546 * (for the ascii descriptions) and the state model enforcer: 547 * scsi_host_set_state() 548 */ 549 enum scsi_host_state { 550 SHOST_CREATED = 1, 551 SHOST_RUNNING, 552 SHOST_CANCEL, 553 SHOST_DEL, 554 SHOST_RECOVERY, 555 SHOST_CANCEL_RECOVERY, 556 SHOST_DEL_RECOVERY, 557 }; 558 559 struct Scsi_Host { 560 /* 561 * __devices is protected by the host_lock, but you should 562 * usually use scsi_device_lookup / shost_for_each_device 563 * to access it and don't care about locking yourself. 564 * In the rare case of being in irq context you can use 565 * their __ prefixed variants with the lock held. NEVER 566 * access this list directly from a driver. 567 */ 568 struct list_head __devices; 569 struct list_head __targets; 570 571 struct list_head starved_list; 572 573 spinlock_t host_lock; 574 575 struct mutex scan_mutex;/* serialize scanning activity */ 576 577 struct list_head eh_abort_list; 578 struct list_head eh_cmd_q; 579 struct task_struct * ehandler; /* Error recovery thread. */ 580 struct completion * eh_action; /* Wait for specific actions on the 581 host. */ 582 wait_queue_head_t host_wait; 583 const struct scsi_host_template *hostt; 584 struct scsi_transport_template *transportt; 585 586 struct kref tagset_refcnt; 587 struct completion tagset_freed; 588 /* Area to keep a shared tag map */ 589 struct blk_mq_tag_set tag_set; 590 591 atomic_t host_blocked; 592 593 unsigned int host_failed; /* commands that failed. 594 protected by host_lock */ 595 unsigned int host_eh_scheduled; /* EH scheduled without command */ 596 597 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 598 599 /* next two fields are used to bound the time spent in error handling */ 600 int eh_deadline; 601 unsigned long last_reset; 602 603 604 /* 605 * These three parameters can be used to allow for wide scsi, 606 * and for host adapters that support multiple busses 607 * The last two should be set to 1 more than the actual max id 608 * or lun (e.g. 8 for SCSI parallel systems). 609 */ 610 unsigned int max_channel; 611 unsigned int max_id; 612 u64 max_lun; 613 614 /* 615 * This is a unique identifier that must be assigned so that we 616 * have some way of identifying each detected host adapter properly 617 * and uniquely. For hosts that do not support more than one card 618 * in the system at one time, this does not need to be set. It is 619 * initialized to 0 in scsi_host_alloc. 620 */ 621 unsigned int unique_id; 622 623 /* 624 * The maximum length of SCSI commands that this host can accept. 625 * Probably 12 for most host adapters, but could be 16 for others. 626 * or 260 if the driver supports variable length cdbs. 627 * For drivers that don't set this field, a value of 12 is 628 * assumed. 629 */ 630 unsigned short max_cmd_len; 631 632 int this_id; 633 634 /* 635 * Number of commands this host can handle at the same time. 636 * This excludes reserved commands as specified by nr_reserved_cmds. 637 */ 638 int can_queue; 639 /* 640 * Number of reserved commands to allocate, if any. 641 */ 642 unsigned int nr_reserved_cmds; 643 644 short cmd_per_lun; 645 short unsigned int sg_tablesize; 646 short unsigned int sg_prot_tablesize; 647 unsigned int max_sectors; 648 unsigned int opt_sectors; 649 unsigned int max_segment_size; 650 unsigned int dma_alignment; 651 unsigned long dma_boundary; 652 unsigned long virt_boundary_mask; 653 /* 654 * In scsi-mq mode, the number of hardware queues supported by the LLD. 655 * 656 * Note: it is assumed that each hardware queue has a queue depth of 657 * can_queue. In other words, the total queue depth per host 658 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 659 * the total queue depth is can_queue. 660 */ 661 unsigned nr_hw_queues; 662 unsigned nr_maps; 663 664 /* Asynchronous scan in progress */ 665 bool async_scan __guarded_by(&scan_mutex); 666 667 /* Don't resume host in EH */ 668 bool eh_noresume; 669 670 unsigned active_mode:2; 671 672 /* 673 * Host has requested that no further requests come through for the 674 * time being. 675 */ 676 unsigned host_self_blocked:1; 677 678 /* 679 * Host uses correct SCSI ordering not PC ordering. The bit is 680 * set for the minority of drivers whose authors actually read 681 * the spec ;). 682 */ 683 unsigned reverse_ordering:1; 684 685 /* Task mgmt function in progress */ 686 unsigned tmf_in_progress:1; 687 688 /* The controller does not support WRITE SAME */ 689 unsigned no_write_same:1; 690 691 /* True if the host uses host-wide tagspace */ 692 unsigned host_tagset:1; 693 694 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 695 unsigned queuecommand_may_block:1; 696 697 /* Host responded with short (<36 bytes) INQUIRY result */ 698 unsigned short_inquiry:1; 699 700 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 701 unsigned no_scsi2_lun_in_cdb:1; 702 703 /* 704 * Optional work queue to be utilized by the transport 705 */ 706 struct workqueue_struct *work_q; 707 708 /* 709 * Task management function work queue 710 */ 711 struct workqueue_struct *tmf_work_q; 712 713 /* 714 * Value host_blocked counts down from 715 */ 716 unsigned int max_host_blocked; 717 718 /* Protection Information */ 719 unsigned int prot_capabilities; 720 unsigned char prot_guard_type; 721 722 /* legacy crap */ 723 unsigned long base; 724 unsigned long io_port; 725 unsigned char n_io_port; 726 unsigned char dma_channel; 727 unsigned int irq; 728 729 730 enum scsi_host_state shost_state __guarded_by(host_lock); 731 732 /* ldm bits */ 733 struct device shost_gendev, shost_dev; 734 735 /* 736 * A SCSI device structure used for sending internal commands to the 737 * HBA. There is no corresponding logical unit inside the SCSI device. 738 */ 739 struct scsi_device *pseudo_sdev; 740 741 /* 742 * Points to the transport data (if any) which is allocated 743 * separately 744 */ 745 void *shost_data; 746 747 /* 748 * Points to the physical bus device we'd use to do DMA 749 * Needed just in case we have virtual hosts. 750 */ 751 struct device *dma_dev; 752 753 /* Used for an rcu-synchronizing eh wakeup */ 754 struct work_struct eh_work; 755 756 /* Delay for runtime autosuspend */ 757 int rpm_autosuspend_delay; 758 759 /* 760 * We should ensure that this is aligned, both for better performance 761 * and also because some compilers (m68k) don't automatically force 762 * alignment to a long boundary. 763 */ 764 unsigned long hostdata[] /* Used for storage of host specific stuff */ 765 __attribute__ ((aligned (sizeof(unsigned long)))); 766 }; 767 768 #define class_to_shost(d) \ 769 container_of(d, struct Scsi_Host, shost_dev) 770 771 #define shost_printk(prefix, shost, fmt, a...) \ 772 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 773 774 static inline void *shost_priv(struct Scsi_Host *shost) 775 { 776 return (void *)shost->hostdata; 777 } 778 779 int scsi_is_host_device(const struct device *); 780 781 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 782 { 783 while (!scsi_is_host_device(dev)) { 784 if (!dev->parent) 785 return NULL; 786 dev = dev->parent; 787 } 788 return container_of(dev, struct Scsi_Host, shost_gendev); 789 } 790 791 static inline enum scsi_host_state scsi_get_host_state(struct Scsi_Host *shost) 792 { 793 return context_unsafe(READ_ONCE(shost->shost_state)); 794 } 795 796 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 797 { 798 enum scsi_host_state state = scsi_get_host_state(shost); 799 800 return state == SHOST_RECOVERY || 801 state == SHOST_CANCEL_RECOVERY || 802 state == SHOST_DEL_RECOVERY || 803 shost->tmf_in_progress; 804 } 805 806 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 807 extern void scsi_flush_work(struct Scsi_Host *); 808 809 extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int); 810 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 811 struct device *, 812 struct device *); 813 #if defined(CONFIG_SCSI_PROC_FS) 814 struct proc_dir_entry * 815 scsi_template_proc_dir(const struct scsi_host_template *sht); 816 #else 817 #define scsi_template_proc_dir(sht) NULL 818 #endif 819 extern void scsi_scan_host(struct Scsi_Host *); 820 extern int scsi_resume_device(struct scsi_device *sdev); 821 extern int scsi_rescan_device(struct scsi_device *sdev); 822 extern void scsi_remove_host(struct Scsi_Host *); 823 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 824 extern int scsi_host_busy(struct Scsi_Host *shost); 825 extern void scsi_host_put(struct Scsi_Host *t); 826 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum); 827 extern const char *scsi_host_state_name(enum scsi_host_state); 828 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 829 enum scsi_host_status status); 830 831 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 832 struct device *dev) 833 { 834 return scsi_add_host_with_dma(host, dev, dev); 835 } 836 837 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 838 { 839 return shost->shost_gendev.parent; 840 } 841 842 /** 843 * scsi_host_scan_allowed - Is scanning of this host allowed 844 * @shost: Pointer to Scsi_Host. 845 **/ 846 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 847 { 848 enum scsi_host_state state = scsi_get_host_state(shost); 849 850 return state == SHOST_RUNNING || state == SHOST_RECOVERY; 851 } 852 853 extern void scsi_unblock_requests(struct Scsi_Host *); 854 extern void scsi_block_requests(struct Scsi_Host *); 855 extern int scsi_host_block(struct Scsi_Host *shost); 856 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 857 858 void scsi_host_busy_iter(struct Scsi_Host *, 859 bool (*fn)(struct scsi_cmnd *, void *), void *priv); 860 861 struct class_container; 862 863 /* 864 * DIF defines the exchange of protection information between 865 * initiator and SBC block device. 866 * 867 * DIX defines the exchange of protection information between OS and 868 * initiator. 869 */ 870 enum scsi_host_prot_capabilities { 871 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 872 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 873 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 874 875 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 876 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 877 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 878 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 879 }; 880 881 /* 882 * SCSI hosts which support the Data Integrity Extensions must 883 * indicate their capabilities by setting the prot_capabilities using 884 * this call. 885 */ 886 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 887 { 888 shost->prot_capabilities = mask; 889 } 890 891 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 892 { 893 return shost->prot_capabilities; 894 } 895 896 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 897 { 898 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 899 } 900 901 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 902 { 903 static unsigned char cap[] = { 0, 904 SHOST_DIF_TYPE1_PROTECTION, 905 SHOST_DIF_TYPE2_PROTECTION, 906 SHOST_DIF_TYPE3_PROTECTION }; 907 908 if (target_type >= ARRAY_SIZE(cap)) 909 return 0; 910 911 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 912 } 913 914 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 915 { 916 #if defined(CONFIG_BLK_DEV_INTEGRITY) 917 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 918 SHOST_DIX_TYPE1_PROTECTION, 919 SHOST_DIX_TYPE2_PROTECTION, 920 SHOST_DIX_TYPE3_PROTECTION }; 921 922 if (target_type >= ARRAY_SIZE(cap)) 923 return 0; 924 925 return shost->prot_capabilities & cap[target_type]; 926 #endif 927 return 0; 928 } 929 930 /* 931 * All DIX-capable initiators must support the T10-mandated CRC 932 * checksum. Controllers can optionally implement the IP checksum 933 * scheme which has much lower impact on system performance. Note 934 * that the main rationale for the checksum is to match integrity 935 * metadata with data. Detecting bit errors are a job for ECC memory 936 * and buses. 937 */ 938 939 enum scsi_host_guard_type { 940 SHOST_DIX_GUARD_CRC = 1 << 0, 941 SHOST_DIX_GUARD_IP = 1 << 1, 942 }; 943 944 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 945 { 946 shost->prot_guard_type = type; 947 } 948 949 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 950 { 951 return shost->prot_guard_type; 952 } 953 954 int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state) 955 __must_hold(&shost->host_lock); 956 957 #endif /* _SCSI_SCSI_HOST_H */ 958