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Ke Dongeb337a32012-09-26 19:17:39 -07001#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 <scsi/scsi.h>
10
11struct request_queue;
12struct block_device;
13struct completion;
14struct module;
15struct scsi_cmnd;
16struct scsi_device;
17struct scsi_target;
18struct Scsi_Host;
19struct scsi_host_cmd_pool;
20struct scsi_transport_template;
21struct blk_queue_tags;
22
23
24/*
25 * The various choices mean:
26 * NONE: Self evident. Host adapter is not capable of scatter-gather.
27 * ALL: Means that the host adapter module can do scatter-gather,
28 * and that there is no limit to the size of the table to which
29 * we scatter/gather data. The value we set here is the maximum
30 * single element sglist. To use chained sglists, the adapter
31 * has to set a value beyond ALL (and correctly use the chain
32 * handling API.
33 * Anything else: Indicates the maximum number of chains that can be
34 * used in one scatter-gather request.
35 */
36#define SG_NONE 0
37#define SG_ALL SCSI_MAX_SG_SEGMENTS
38
39#define MODE_UNKNOWN 0x00
40#define MODE_INITIATOR 0x01
41#define MODE_TARGET 0x02
42
43#define DISABLE_CLUSTERING 0
44#define ENABLE_CLUSTERING 1
45
46struct scsi_host_template {
47 struct module *module;
48 const char *name;
49
50 /*
Ke Dongd0456642012-09-26 19:22:56 -070051 * support to scattered spinup in various drivers
52 */
53 unsigned char support_scattered_spinup;
54
55 /*
Ke Dongeb337a32012-09-26 19:17:39 -070056 * Used to initialize old-style drivers. For new-style drivers
57 * just perform all work in your module initialization function.
58 *
59 * Status: OBSOLETE
60 */
61 int (* detect)(struct scsi_host_template *);
62
63 /*
64 * Used as unload callback for hosts with old-style drivers.
65 *
66 * Status: OBSOLETE
67 */
68 int (* release)(struct Scsi_Host *);
69
70 /*
71 * The info function will return whatever useful information the
72 * developer sees fit. If not provided, then the name field will
73 * be used instead.
74 *
75 * Status: OPTIONAL
76 */
77 const char *(* info)(struct Scsi_Host *);
78
79 /*
80 * Ioctl interface
81 *
82 * Status: OPTIONAL
83 */
84 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
85
86
87#ifdef CONFIG_COMPAT
88 /*
89 * Compat handler. Handle 32bit ABI.
90 * When unknown ioctl is passed return -ENOIOCTLCMD.
91 *
92 * Status: OPTIONAL
93 */
94 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
95#endif
96
97 /*
98 * The queuecommand function is used to queue up a scsi
99 * command block to the LLDD. When the driver finished
100 * processing the command the done callback is invoked.
101 *
102 * If queuecommand returns 0, then the HBA has accepted the
103 * command. The done() function must be called on the command
104 * when the driver has finished with it. (you may call done on the
105 * command before queuecommand returns, but in this case you
106 * *must* return 0 from queuecommand).
107 *
108 * Queuecommand may also reject the command, in which case it may
109 * not touch the command and must not call done() for it.
110 *
111 * There are two possible rejection returns:
112 *
113 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
114 * allow commands to other devices serviced by this host.
115 *
116 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
117 * host temporarily.
118 *
119 * For compatibility, any other non-zero return is treated the
120 * same as SCSI_MLQUEUE_HOST_BUSY.
121 *
122 * NOTE: "temporarily" means either until the next command for#
123 * this device/host completes, or a period of time determined by
124 * I/O pressure in the system if there are no other outstanding
125 * commands.
126 *
127 * STATUS: REQUIRED
128 */
129 int (* queuecommand)(struct scsi_cmnd *,
130 void (*done)(struct scsi_cmnd *));
131
132 /*
133 * The transfer functions are used to queue a scsi command to
134 * the LLD. When the driver is finished processing the command
135 * the done callback is invoked.
136 *
137 * This is called to inform the LLD to transfer
138 * scsi_bufflen(cmd) bytes. scsi_sg_count(cmd) speciefies the
139 * number of scatterlist entried in the command and
140 * scsi_sglist(cmd) returns the scatterlist.
141 *
142 * return values: see queuecommand
143 *
144 * If the LLD accepts the cmd, it should set the result to an
145 * appropriate value when completed before calling the done function.
146 *
147 * STATUS: REQUIRED FOR TARGET DRIVERS
148 */
149 /* TODO: rename */
150 int (* transfer_response)(struct scsi_cmnd *,
151 void (*done)(struct scsi_cmnd *));
152
153 /*
154 * This is an error handling strategy routine. You don't need to
155 * define one of these if you don't want to - there is a default
156 * routine that is present that should work in most cases. For those
157 * driver authors that have the inclination and ability to write their
158 * own strategy routine, this is where it is specified. Note - the
159 * strategy routine is *ALWAYS* run in the context of the kernel eh
160 * thread. Thus you are guaranteed to *NOT* be in an interrupt
161 * handler when you execute this, and you are also guaranteed to
162 * *NOT* have any other commands being queued while you are in the
163 * strategy routine. When you return from this function, operations
164 * return to normal.
165 *
166 * See scsi_error.c scsi_unjam_host for additional comments about
167 * what this function should and should not be attempting to do.
168 *
169 * Status: REQUIRED (at least one of them)
170 */
171 int (* eh_abort_handler)(struct scsi_cmnd *);
172 int (* eh_device_reset_handler)(struct scsi_cmnd *);
173 int (* eh_target_reset_handler)(struct scsi_cmnd *);
174 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
175 int (* eh_host_reset_handler)(struct scsi_cmnd *);
176
177 /*
178 * Before the mid layer attempts to scan for a new device where none
179 * currently exists, it will call this entry in your driver. Should
180 * your driver need to allocate any structs or perform any other init
181 * items in order to send commands to a currently unused target/lun
182 * combo, then this is where you can perform those allocations. This
183 * is specifically so that drivers won't have to perform any kind of
184 * "is this a new device" checks in their queuecommand routine,
185 * thereby making the hot path a bit quicker.
186 *
187 * Return values: 0 on success, non-0 on failure
188 *
189 * Deallocation: If we didn't find any devices at this ID, you will
190 * get an immediate call to slave_destroy(). If we find something
191 * here then you will get a call to slave_configure(), then the
192 * device will be used for however long it is kept around, then when
193 * the device is removed from the system (or * possibly at reboot
194 * time), you will then get a call to slave_destroy(). This is
195 * assuming you implement slave_configure and slave_destroy.
196 * However, if you allocate memory and hang it off the device struct,
197 * then you must implement the slave_destroy() routine at a minimum
198 * in order to avoid leaking memory
199 * each time a device is tore down.
200 *
201 * Status: OPTIONAL
202 */
203 int (* slave_alloc)(struct scsi_device *);
204
205 /*
206 * Once the device has responded to an INQUIRY and we know the
207 * device is online, we call into the low level driver with the
208 * struct scsi_device *. If the low level device driver implements
209 * this function, it *must* perform the task of setting the queue
210 * depth on the device. All other tasks are optional and depend
211 * on what the driver supports and various implementation details.
212 *
213 * Things currently recommended to be handled at this time include:
214 *
215 * 1. Setting the device queue depth. Proper setting of this is
216 * described in the comments for scsi_adjust_queue_depth.
217 * 2. Determining if the device supports the various synchronous
218 * negotiation protocols. The device struct will already have
219 * responded to INQUIRY and the results of the standard items
220 * will have been shoved into the various device flag bits, eg.
221 * device->sdtr will be true if the device supports SDTR messages.
222 * 3. Allocating command structs that the device will need.
223 * 4. Setting the default timeout on this device (if needed).
224 * 5. Anything else the low level driver might want to do on a device
225 * specific setup basis...
226 * 6. Return 0 on success, non-0 on error. The device will be marked
227 * as offline on error so that no access will occur. If you return
228 * non-0, your slave_destroy routine will never get called for this
229 * device, so don't leave any loose memory hanging around, clean
230 * up after yourself before returning non-0
231 *
232 * Status: OPTIONAL
233 */
234 int (* slave_configure)(struct scsi_device *);
235
236 /*
237 * Immediately prior to deallocating the device and after all activity
238 * has ceased the mid layer calls this point so that the low level
239 * driver may completely detach itself from the scsi device and vice
240 * versa. The low level driver is responsible for freeing any memory
241 * it allocated in the slave_alloc or slave_configure calls.
242 *
243 * Status: OPTIONAL
244 */
245 void (* slave_destroy)(struct scsi_device *);
246
247 /*
248 * Before the mid layer attempts to scan for a new device attached
249 * to a target where no target currently exists, it will call this
250 * entry in your driver. Should your driver need to allocate any
251 * structs or perform any other init items in order to send commands
252 * to a currently unused target, then this is where you can perform
253 * those allocations.
254 *
255 * Return values: 0 on success, non-0 on failure
256 *
257 * Status: OPTIONAL
258 */
259 int (* target_alloc)(struct scsi_target *);
260
261 /*
262 * Immediately prior to deallocating the target structure, and
263 * after all activity to attached scsi devices has ceased, the
264 * midlayer calls this point so that the driver may deallocate
265 * and terminate any references to the target.
266 *
267 * Status: OPTIONAL
268 */
269 void (* target_destroy)(struct scsi_target *);
270
271 /*
272 * If a host has the ability to discover targets on its own instead
273 * of scanning the entire bus, it can fill in this function and
274 * call scsi_scan_host(). This function will be called periodically
275 * until it returns 1 with the scsi_host and the elapsed time of
276 * the scan in jiffies.
277 *
278 * Status: OPTIONAL
279 */
280 int (* scan_finished)(struct Scsi_Host *, unsigned long);
281
282 /*
283 * If the host wants to be called before the scan starts, but
284 * after the midlayer has set up ready for the scan, it can fill
285 * in this function.
286 *
287 * Status: OPTIONAL
288 */
289 void (* scan_start)(struct Scsi_Host *);
290
291 /*
292 * Fill in this function to allow the queue depth of this host
293 * to be changeable (on a per device basis). Returns either
294 * the current queue depth setting (may be different from what
295 * was passed in) or an error. An error should only be
296 * returned if the requested depth is legal but the driver was
297 * unable to set it. If the requested depth is illegal, the
298 * driver should set and return the closest legal queue depth.
299 *
300 * Status: OPTIONAL
301 */
302 int (* change_queue_depth)(struct scsi_device *, int);
303
304 /*
305 * Fill in this function to allow the changing of tag types
306 * (this also allows the enabling/disabling of tag command
307 * queueing). An error should only be returned if something
308 * went wrong in the driver while trying to set the tag type.
309 * If the driver doesn't support the requested tag type, then
310 * it should set the closest type it does support without
311 * returning an error. Returns the actual tag type set.
312 *
313 * Status: OPTIONAL
314 */
315 int (* change_queue_type)(struct scsi_device *, int);
316
317 /*
318 * This function determines the BIOS parameters for a given
319 * harddisk. These tend to be numbers that are made up by
320 * the host adapter. Parameters:
321 * size, device, list (heads, sectors, cylinders)
322 *
323 * Status: OPTIONAL
324 */
325 int (* bios_param)(struct scsi_device *, struct block_device *,
326 sector_t, int []);
327
328 /*
329 * Can be used to export driver statistics and other infos to the
330 * world outside the kernel ie. userspace and it also provides an
331 * interface to feed the driver with information.
332 *
333 * Status: OBSOLETE
334 */
335 int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int);
336
337 /*
338 * This is an optional routine that allows the transport to become
339 * involved when a scsi io timer fires. The return value tells the
340 * timer routine how to finish the io timeout handling:
341 * EH_HANDLED: I fixed the error, please complete the command
342 * EH_RESET_TIMER: I need more time, reset the timer and
343 * begin counting again
344 * EH_NOT_HANDLED Begin normal error recovery
345 *
346 * Status: OPTIONAL
347 */
348 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
349
350 /*
351 * Name of proc directory
352 */
353 const char *proc_name;
354
355 /*
356 * Used to store the procfs directory if a driver implements the
357 * proc_info method.
358 */
359 struct proc_dir_entry *proc_dir;
360
361 /*
362 * This determines if we will use a non-interrupt driven
363 * or an interrupt driven scheme. It is set to the maximum number
364 * of simultaneous commands a given host adapter will accept.
365 */
366 int can_queue;
367
368 /*
369 * In many instances, especially where disconnect / reconnect are
370 * supported, our host also has an ID on the SCSI bus. If this is
371 * the case, then it must be reserved. Please set this_id to -1 if
372 * your setup is in single initiator mode, and the host lacks an
373 * ID.
374 */
375 int this_id;
376
377 /*
378 * This determines the degree to which the host adapter is capable
379 * of scatter-gather.
380 */
381 unsigned short sg_tablesize;
382
383 /*
384 * Set this if the host adapter has limitations beside segment count.
385 */
386 unsigned short max_sectors;
387
388 /*
389 * DMA scatter gather segment boundary limit. A segment crossing this
390 * boundary will be split in two.
391 */
392 unsigned long dma_boundary;
393
394 /*
395 * This specifies "machine infinity" for host templates which don't
396 * limit the transfer size. Note this limit represents an absolute
397 * maximum, and may be over the transfer limits allowed for
398 * individual devices (e.g. 256 for SCSI-1).
399 */
400#define SCSI_DEFAULT_MAX_SECTORS 1024
401
402 /*
403 * True if this host adapter can make good use of linked commands.
404 * This will allow more than one command to be queued to a given
405 * unit on a given host. Set this to the maximum number of command
406 * blocks to be provided for each device. Set this to 1 for one
407 * command block per lun, 2 for two, etc. Do not set this to 0.
408 * You should make sure that the host adapter will do the right thing
409 * before you try setting this above 1.
410 */
411 short cmd_per_lun;
412
413 /*
414 * present contains counter indicating how many boards of this
415 * type were found when we did the scan.
416 */
417 unsigned char present;
418
419 /*
420 * This specifies the mode that a LLD supports.
421 */
422 unsigned supported_mode:2;
423
424 /*
425 * True if this host adapter uses unchecked DMA onto an ISA bus.
426 */
427 unsigned unchecked_isa_dma:1;
428
429 /*
430 * True if this host adapter can make good use of clustering.
431 * I originally thought that if the tablesize was large that it
432 * was a waste of CPU cycles to prepare a cluster list, but
433 * it works out that the Buslogic is faster if you use a smaller
434 * number of segments (i.e. use clustering). I guess it is
435 * inefficient.
436 */
437 unsigned use_clustering:1;
438
439 /*
440 * True for emulated SCSI host adapters (e.g. ATAPI).
441 */
442 unsigned emulated:1;
443
444 /*
445 * True if the low-level driver performs its own reset-settle delays.
446 */
447 unsigned skip_settle_delay:1;
448
449 /*
450 * True if we are using ordered write support.
451 */
452 unsigned ordered_tag:1;
453
454 /*
455 * Countdown for host blocking with no commands outstanding.
456 */
457 unsigned int max_host_blocked;
458
459 /*
460 * Default value for the blocking. If the queue is empty,
461 * host_blocked counts down in the request_fn until it restarts
462 * host operations as zero is reached.
463 *
464 * FIXME: This should probably be a value in the template
465 */
466#define SCSI_DEFAULT_HOST_BLOCKED 7
467
468 /*
469 * Pointer to the sysfs class properties for this host, NULL terminated.
470 */
471 struct device_attribute **shost_attrs;
472
473 /*
474 * Pointer to the SCSI device properties for this host, NULL terminated.
475 */
476 struct device_attribute **sdev_attrs;
477
478 /*
479 * List of hosts per template.
480 *
481 * This is only for use by scsi_module.c for legacy templates.
482 * For these access to it is synchronized implicitly by
483 * module_init/module_exit.
484 */
485 struct list_head legacy_hosts;
486
487 /*
488 * Vendor Identifier associated with the host
489 *
490 * Note: When specifying vendor_id, be sure to read the
491 * Vendor Type and ID formatting requirements specified in
492 * scsi_netlink.h
493 */
494 u64 vendor_id;
495};
496
497/*
498 * shost state: If you alter this, you also need to alter scsi_sysfs.c
499 * (for the ascii descriptions) and the state model enforcer:
500 * scsi_host_set_state()
501 */
502enum scsi_host_state {
503 SHOST_CREATED = 1,
504 SHOST_RUNNING,
505 SHOST_CANCEL,
506 SHOST_DEL,
507 SHOST_RECOVERY,
508 SHOST_CANCEL_RECOVERY,
509 SHOST_DEL_RECOVERY,
510};
511
512struct Scsi_Host {
513 /*
514 * __devices is protected by the host_lock, but you should
515 * usually use scsi_device_lookup / shost_for_each_device
516 * to access it and don't care about locking yourself.
517 * In the rare case of beeing in irq context you can use
518 * their __ prefixed variants with the lock held. NEVER
519 * access this list directly from a driver.
520 */
521 struct list_head __devices;
522 struct list_head __targets;
523
524 struct scsi_host_cmd_pool *cmd_pool;
525 spinlock_t free_list_lock;
526 struct list_head free_list; /* backup store of cmd structs */
527 struct list_head starved_list;
528
529 spinlock_t default_lock;
530 spinlock_t *host_lock;
531
532 struct mutex scan_mutex;/* serialize scanning activity */
533
534 struct list_head eh_cmd_q;
535 struct task_struct * ehandler; /* Error recovery thread. */
536 struct completion * eh_action; /* Wait for specific actions on the
537 host. */
538 wait_queue_head_t host_wait;
539 struct scsi_host_template *hostt;
540 struct scsi_transport_template *transportt;
541
542 /*
543 * Area to keep a shared tag map (if needed, will be
544 * NULL if not).
545 */
546 struct blk_queue_tag *bqt;
547
548 /*
549 * The following two fields are protected with host_lock;
550 * however, eh routines can safely access during eh processing
551 * without acquiring the lock.
552 */
553 unsigned int host_busy; /* commands actually active on low-level */
554 unsigned int host_failed; /* commands that failed. */
555 unsigned int host_eh_scheduled; /* EH scheduled without command */
556
557 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
558 int resetting; /* if set, it means that last_reset is a valid value */
559 unsigned long last_reset;
560
561 /*
562 * These three parameters can be used to allow for wide scsi,
563 * and for host adapters that support multiple busses
564 * The first two should be set to 1 more than the actual max id
565 * or lun (i.e. 8 for normal systems).
566 */
567 unsigned int max_id;
568 unsigned int max_lun;
569 unsigned int max_channel;
570
571 /*
572 * This is a unique identifier that must be assigned so that we
573 * have some way of identifying each detected host adapter properly
574 * and uniquely. For hosts that do not support more than one card
575 * in the system at one time, this does not need to be set. It is
576 * initialized to 0 in scsi_register.
577 */
578 unsigned int unique_id;
579
580 /*
581 * The maximum length of SCSI commands that this host can accept.
582 * Probably 12 for most host adapters, but could be 16 for others.
583 * or 260 if the driver supports variable length cdbs.
584 * For drivers that don't set this field, a value of 12 is
585 * assumed.
586 */
587 unsigned short max_cmd_len;
588
589 int this_id;
590 int can_queue;
591 short cmd_per_lun;
592 short unsigned int sg_tablesize;
593 short unsigned int max_sectors;
594 unsigned long dma_boundary;
595 /*
596 * Used to assign serial numbers to the cmds.
597 * Protected by the host lock.
598 */
599 unsigned long cmd_serial_number;
600
601 unsigned active_mode:2;
602 unsigned unchecked_isa_dma:1;
603 unsigned use_clustering:1;
604 unsigned use_blk_tcq:1;
605
606 /*
607 * Host has requested that no further requests come through for the
608 * time being.
609 */
610 unsigned host_self_blocked:1;
611
612 /*
613 * Host uses correct SCSI ordering not PC ordering. The bit is
614 * set for the minority of drivers whose authors actually read
615 * the spec ;).
616 */
617 unsigned reverse_ordering:1;
618
619 /*
620 * Ordered write support
621 */
622 unsigned ordered_tag:1;
623
624 /* Task mgmt function in progress */
625 unsigned tmf_in_progress:1;
626
627 /* Asynchronous scan in progress */
628 unsigned async_scan:1;
629
630 /*
631 * Optional work queue to be utilized by the transport
632 */
633 char work_q_name[20];
634 struct workqueue_struct *work_q;
635
636 /*
637 * Host has rejected a command because it was busy.
638 */
639 unsigned int host_blocked;
640
641 /*
642 * Value host_blocked counts down from
643 */
644 unsigned int max_host_blocked;
645
646 /* Protection Information */
647 unsigned int prot_capabilities;
648 unsigned char prot_guard_type;
649
650 /*
651 * q used for scsi_tgt msgs, async events or any other requests that
652 * need to be processed in userspace
653 */
654 struct request_queue *uspace_req_q;
655
656 /* legacy crap */
657 unsigned long base;
658 unsigned long io_port;
659 unsigned char n_io_port;
660 unsigned char dma_channel;
661 unsigned int irq;
662
663
664 enum scsi_host_state shost_state;
665
666 /* ldm bits */
667 struct device shost_gendev, shost_dev;
668
669 /*
670 * List of hosts per template.
671 *
672 * This is only for use by scsi_module.c for legacy templates.
673 * For these access to it is synchronized implicitly by
674 * module_init/module_exit.
675 */
676 struct list_head sht_legacy_list;
677
678 /*
679 * Points to the transport data (if any) which is allocated
680 * separately
681 */
682 void *shost_data;
683
684 /*
685 * Points to the physical bus device we'd use to do DMA
686 * Needed just in case we have virtual hosts.
687 */
688 struct device *dma_dev;
689
690 /*
691 * We should ensure that this is aligned, both for better performance
692 * and also because some compilers (m68k) don't automatically force
693 * alignment to a long boundary.
694 */
695 unsigned long hostdata[0] /* Used for storage of host specific stuff */
696 __attribute__ ((aligned (sizeof(unsigned long))));
697};
698
699#define class_to_shost(d) \
700 container_of(d, struct Scsi_Host, shost_dev)
701
702#define shost_printk(prefix, shost, fmt, a...) \
703 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
704
705static inline void *shost_priv(struct Scsi_Host *shost)
706{
707 return (void *)shost->hostdata;
708}
709
710int scsi_is_host_device(const struct device *);
711
712static inline struct Scsi_Host *dev_to_shost(struct device *dev)
713{
714 while (!scsi_is_host_device(dev)) {
715 if (!dev->parent)
716 return NULL;
717 dev = dev->parent;
718 }
719 return container_of(dev, struct Scsi_Host, shost_gendev);
720}
721
722static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
723{
724 return shost->shost_state == SHOST_RECOVERY ||
725 shost->shost_state == SHOST_CANCEL_RECOVERY ||
726 shost->shost_state == SHOST_DEL_RECOVERY ||
727 shost->tmf_in_progress;
728}
729
730extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
731extern void scsi_flush_work(struct Scsi_Host *);
732
733extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
734extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
735 struct device *,
736 struct device *);
737extern void scsi_scan_host(struct Scsi_Host *);
738extern void scsi_rescan_device(struct device *);
739extern void scsi_remove_host(struct Scsi_Host *);
740extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
741extern void scsi_host_put(struct Scsi_Host *t);
742extern struct Scsi_Host *scsi_host_lookup(unsigned short);
743extern const char *scsi_host_state_name(enum scsi_host_state);
744
745extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
746
747static inline int __must_check scsi_add_host(struct Scsi_Host *host,
748 struct device *dev)
749{
750 return scsi_add_host_with_dma(host, dev, dev);
751}
752
753static inline struct device *scsi_get_device(struct Scsi_Host *shost)
754{
755 return shost->shost_gendev.parent;
756}
757
758/**
759 * scsi_host_scan_allowed - Is scanning of this host allowed
760 * @shost: Pointer to Scsi_Host.
761 **/
762static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
763{
764 return shost->shost_state == SHOST_RUNNING;
765}
766
767extern void scsi_unblock_requests(struct Scsi_Host *);
768extern void scsi_block_requests(struct Scsi_Host *);
769
770struct class_container;
771
772extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
773 void (*) (struct request_queue *));
774/*
775 * These two functions are used to allocate and free a pseudo device
776 * which will connect to the host adapter itself rather than any
777 * physical device. You must deallocate when you are done with the
778 * thing. This physical pseudo-device isn't real and won't be available
779 * from any high-level drivers.
780 */
781extern void scsi_free_host_dev(struct scsi_device *);
782extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
783
784/*
785 * DIF defines the exchange of protection information between
786 * initiator and SBC block device.
787 *
788 * DIX defines the exchange of protection information between OS and
789 * initiator.
790 */
791enum scsi_host_prot_capabilities {
792 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
793 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
794 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
795
796 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
797 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
798 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
799 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
800};
801
802/*
803 * SCSI hosts which support the Data Integrity Extensions must
804 * indicate their capabilities by setting the prot_capabilities using
805 * this call.
806 */
807static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
808{
809 shost->prot_capabilities = mask;
810}
811
812static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
813{
814 return shost->prot_capabilities;
815}
816
817static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
818{
819 static unsigned char cap[] = { 0,
820 SHOST_DIF_TYPE1_PROTECTION,
821 SHOST_DIF_TYPE2_PROTECTION,
822 SHOST_DIF_TYPE3_PROTECTION };
823
824 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
825}
826
827static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
828{
829#if defined(CONFIG_BLK_DEV_INTEGRITY)
830 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
831 SHOST_DIX_TYPE1_PROTECTION,
832 SHOST_DIX_TYPE2_PROTECTION,
833 SHOST_DIX_TYPE3_PROTECTION };
834
835 return shost->prot_capabilities & cap[target_type];
836#endif
837 return 0;
838}
839
840/*
841 * All DIX-capable initiators must support the T10-mandated CRC
842 * checksum. Controllers can optionally implement the IP checksum
843 * scheme which has much lower impact on system performance. Note
844 * that the main rationale for the checksum is to match integrity
845 * metadata with data. Detecting bit errors are a job for ECC memory
846 * and buses.
847 */
848
849enum scsi_host_guard_type {
850 SHOST_DIX_GUARD_CRC = 1 << 0,
851 SHOST_DIX_GUARD_IP = 1 << 1,
852};
853
854static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
855{
856 shost->prot_guard_type = type;
857}
858
859static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
860{
861 return shost->prot_guard_type;
862}
863
864/* legacy interfaces */
865extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
866extern void scsi_unregister(struct Scsi_Host *);
867extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
868
869#endif /* _SCSI_SCSI_HOST_H */