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 For new-style drivers 60 * just perform all work in your module initialization function. 61 * 62 * Status: OBSOLETE 63 */ 64 int (* detect)(struct scsi_host_template *); 65 66 /* 67 * Used as unload callback for hosts with old-style drivers. 68 * 69 * Status: OBSOLETE 70 */ 71 int (* release)(struct Scsi_Host *); 72 73 /* 74 * The info function will return whatever useful information the 75 * developer sees fit.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