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 For new-style drivers 59 * just perform all work in your module initialization function. 60 * 61 * Status: OBSOLETE 62 */ 63 int (* detect)(struct scsi_host_template *); 64 65 /* 66 * Used as unload callback for hosts with old-style drivers. 67 * 68 * Status: OBSOLETE 69 */ 70 int (* release)(struct Scsi_Host *); 71 72 /* 73 * The info function will return whatever useful information the 74 * developer sees fit.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