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Linus Torvalds1da177e2005-04-16 15:20:36 -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>
Arjan van de Ven0b950672006-01-11 13:16:10 +01008#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07009
10struct block_device;
Christoph Hellwig7dfdc9a2005-10-31 18:49:52 +010011struct completion;
Linus Torvalds1da177e2005-04-16 15:20:36 -070012struct module;
13struct scsi_cmnd;
14struct scsi_device;
James Bottomleya283bd32005-05-24 12:06:38 -050015struct scsi_target;
Linus Torvalds1da177e2005-04-16 15:20:36 -070016struct Scsi_Host;
17struct scsi_host_cmd_pool;
18struct scsi_transport_template;
19
20
21/*
22 * The various choices mean:
23 * NONE: Self evident. Host adapter is not capable of scatter-gather.
24 * ALL: Means that the host adapter module can do scatter-gather,
25 * and that there is no limit to the size of the table to which
26 * we scatter/gather data.
27 * Anything else: Indicates the maximum number of chains that can be
28 * used in one scatter-gather request.
29 */
30#define SG_NONE 0
31#define SG_ALL 0xff
32
33
34#define DISABLE_CLUSTERING 0
35#define ENABLE_CLUSTERING 1
36
37enum scsi_eh_timer_return {
38 EH_NOT_HANDLED,
39 EH_HANDLED,
40 EH_RESET_TIMER,
41};
42
43
44struct scsi_host_template {
45 struct module *module;
46 const char *name;
47
48 /*
49 * Used to initialize old-style drivers. For new-style drivers
50 * just perform all work in your module initialization function.
51 *
52 * Status: OBSOLETE
53 */
54 int (* detect)(struct scsi_host_template *);
55
56 /*
57 * Used as unload callback for hosts with old-style drivers.
58 *
59 * Status: OBSOLETE
60 */
61 int (* release)(struct Scsi_Host *);
62
63 /*
64 * The info function will return whatever useful information the
65 * developer sees fit. If not provided, then the name field will
66 * be used instead.
67 *
68 * Status: OPTIONAL
69 */
70 const char *(* info)(struct Scsi_Host *);
71
72 /*
73 * Ioctl interface
74 *
75 * Status: OPTIONAL
76 */
77 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
78
79
80#ifdef CONFIG_COMPAT
81 /*
82 * Compat handler. Handle 32bit ABI.
83 * When unknown ioctl is passed return -ENOIOCTLCMD.
84 *
85 * Status: OPTIONAL
86 */
87 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
88#endif
89
90 /*
91 * The queuecommand function is used to queue up a scsi
92 * command block to the LLDD. When the driver finished
93 * processing the command the done callback is invoked.
94 *
95 * If queuecommand returns 0, then the HBA has accepted the
96 * command. The done() function must be called on the command
97 * when the driver has finished with it. (you may call done on the
98 * command before queuecommand returns, but in this case you
99 * *must* return 0 from queuecommand).
100 *
101 * Queuecommand may also reject the command, in which case it may
102 * not touch the command and must not call done() for it.
103 *
104 * There are two possible rejection returns:
105 *
106 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
107 * allow commands to other devices serviced by this host.
108 *
109 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
110 * host temporarily.
111 *
112 * For compatibility, any other non-zero return is treated the
113 * same as SCSI_MLQUEUE_HOST_BUSY.
114 *
115 * NOTE: "temporarily" means either until the next command for#
116 * this device/host completes, or a period of time determined by
117 * I/O pressure in the system if there are no other outstanding
118 * commands.
119 *
120 * STATUS: REQUIRED
121 */
122 int (* queuecommand)(struct scsi_cmnd *,
123 void (*done)(struct scsi_cmnd *));
124
125 /*
126 * This is an error handling strategy routine. You don't need to
127 * define one of these if you don't want to - there is a default
128 * routine that is present that should work in most cases. For those
129 * driver authors that have the inclination and ability to write their
130 * own strategy routine, this is where it is specified. Note - the
131 * strategy routine is *ALWAYS* run in the context of the kernel eh
132 * thread. Thus you are guaranteed to *NOT* be in an interrupt
133 * handler when you execute this, and you are also guaranteed to
134 * *NOT* have any other commands being queued while you are in the
135 * strategy routine. When you return from this function, operations
136 * return to normal.
137 *
138 * See scsi_error.c scsi_unjam_host for additional comments about
139 * what this function should and should not be attempting to do.
140 *
141 * Status: REQUIRED (at least one of them)
142 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 int (* eh_abort_handler)(struct scsi_cmnd *);
144 int (* eh_device_reset_handler)(struct scsi_cmnd *);
145 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
146 int (* eh_host_reset_handler)(struct scsi_cmnd *);
147
148 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 * Before the mid layer attempts to scan for a new device where none
150 * currently exists, it will call this entry in your driver. Should
151 * your driver need to allocate any structs or perform any other init
152 * items in order to send commands to a currently unused target/lun
153 * combo, then this is where you can perform those allocations. This
154 * is specifically so that drivers won't have to perform any kind of
155 * "is this a new device" checks in their queuecommand routine,
156 * thereby making the hot path a bit quicker.
157 *
158 * Return values: 0 on success, non-0 on failure
159 *
160 * Deallocation: If we didn't find any devices at this ID, you will
161 * get an immediate call to slave_destroy(). If we find something
162 * here then you will get a call to slave_configure(), then the
163 * device will be used for however long it is kept around, then when
164 * the device is removed from the system (or * possibly at reboot
165 * time), you will then get a call to slave_destroy(). This is
166 * assuming you implement slave_configure and slave_destroy.
167 * However, if you allocate memory and hang it off the device struct,
168 * then you must implement the slave_destroy() routine at a minimum
169 * in order to avoid leaking memory
170 * each time a device is tore down.
171 *
172 * Status: OPTIONAL
173 */
174 int (* slave_alloc)(struct scsi_device *);
175
176 /*
177 * Once the device has responded to an INQUIRY and we know the
178 * device is online, we call into the low level driver with the
179 * struct scsi_device *. If the low level device driver implements
180 * this function, it *must* perform the task of setting the queue
181 * depth on the device. All other tasks are optional and depend
182 * on what the driver supports and various implementation details.
183 *
184 * Things currently recommended to be handled at this time include:
185 *
186 * 1. Setting the device queue depth. Proper setting of this is
187 * described in the comments for scsi_adjust_queue_depth.
188 * 2. Determining if the device supports the various synchronous
189 * negotiation protocols. The device struct will already have
190 * responded to INQUIRY and the results of the standard items
191 * will have been shoved into the various device flag bits, eg.
192 * device->sdtr will be true if the device supports SDTR messages.
193 * 3. Allocating command structs that the device will need.
194 * 4. Setting the default timeout on this device (if needed).
195 * 5. Anything else the low level driver might want to do on a device
196 * specific setup basis...
197 * 6. Return 0 on success, non-0 on error. The device will be marked
198 * as offline on error so that no access will occur. If you return
199 * non-0, your slave_destroy routine will never get called for this
200 * device, so don't leave any loose memory hanging around, clean
201 * up after yourself before returning non-0
202 *
203 * Status: OPTIONAL
204 */
205 int (* slave_configure)(struct scsi_device *);
206
207 /*
208 * Immediately prior to deallocating the device and after all activity
209 * has ceased the mid layer calls this point so that the low level
210 * driver may completely detach itself from the scsi device and vice
211 * versa. The low level driver is responsible for freeing any memory
212 * it allocated in the slave_alloc or slave_configure calls.
213 *
214 * Status: OPTIONAL
215 */
216 void (* slave_destroy)(struct scsi_device *);
217
218 /*
James Bottomleya283bd32005-05-24 12:06:38 -0500219 * Before the mid layer attempts to scan for a new device attached
220 * to a target where no target currently exists, it will call this
221 * entry in your driver. Should your driver need to allocate any
222 * structs or perform any other init items in order to send commands
223 * to a currently unused target, then this is where you can perform
224 * those allocations.
225 *
226 * Return values: 0 on success, non-0 on failure
227 *
228 * Status: OPTIONAL
229 */
230 int (* target_alloc)(struct scsi_target *);
231
232 /*
233 * Immediately prior to deallocating the target structure, and
234 * after all activity to attached scsi devices has ceased, the
235 * midlayer calls this point so that the driver may deallocate
236 * and terminate any references to the target.
237 *
238 * Status: OPTIONAL
239 */
240 void (* target_destroy)(struct scsi_target *);
241
242 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 * fill in this function to allow the queue depth of this host
244 * to be changeable (on a per device basis). returns either
245 * the current queue depth setting (may be different from what
246 * was passed in) or an error. An error should only be
247 * returned if the requested depth is legal but the driver was
248 * unable to set it. If the requested depth is illegal, the
249 * driver should set and return the closest legal queue depth.
250 *
251 */
252 int (* change_queue_depth)(struct scsi_device *, int);
253
254 /*
255 * fill in this function to allow the changing of tag types
256 * (this also allows the enabling/disabling of tag command
257 * queueing). An error should only be returned if something
258 * went wrong in the driver while trying to set the tag type.
259 * If the driver doesn't support the requested tag type, then
260 * it should set the closest type it does support without
261 * returning an error. Returns the actual tag type set.
262 */
263 int (* change_queue_type)(struct scsi_device *, int);
264
265 /*
266 * This function determines the bios parameters for a given
267 * harddisk. These tend to be numbers that are made up by
268 * the host adapter. Parameters:
269 * size, device, list (heads, sectors, cylinders)
270 *
271 * Status: OPTIONAL */
272 int (* bios_param)(struct scsi_device *, struct block_device *,
273 sector_t, int []);
274
275 /*
276 * Can be used to export driver statistics and other infos to the
277 * world outside the kernel ie. userspace and it also provides an
278 * interface to feed the driver with information.
279 *
280 * Status: OBSOLETE
281 */
282 int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int);
283
284 /*
Jens Axboe9b847542006-01-06 09:28:07 +0100285 * suspend support
286 */
287 int (*resume)(struct scsi_device *);
Nigel Cunningham082776e2006-03-23 23:22:16 +1000288 int (*suspend)(struct scsi_device *, pm_message_t state);
Jens Axboe9b847542006-01-06 09:28:07 +0100289
290 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 * Name of proc directory
292 */
293 char *proc_name;
294
295 /*
296 * Used to store the procfs directory if a driver implements the
297 * proc_info method.
298 */
299 struct proc_dir_entry *proc_dir;
300
301 /*
302 * This determines if we will use a non-interrupt driven
303 * or an interrupt driven scheme, It is set to the maximum number
304 * of simultaneous commands a given host adapter will accept.
305 */
306 int can_queue;
307
308 /*
309 * In many instances, especially where disconnect / reconnect are
310 * supported, our host also has an ID on the SCSI bus. If this is
311 * the case, then it must be reserved. Please set this_id to -1 if
312 * your setup is in single initiator mode, and the host lacks an
313 * ID.
314 */
315 int this_id;
316
317 /*
318 * This determines the degree to which the host adapter is capable
319 * of scatter-gather.
320 */
321 unsigned short sg_tablesize;
322
323 /*
324 * If the host adapter has limitations beside segment count
325 */
326 unsigned short max_sectors;
327
328 /*
329 * dma scatter gather segment boundary limit. a segment crossing this
330 * boundary will be split in two.
331 */
332 unsigned long dma_boundary;
333
334 /*
335 * This specifies "machine infinity" for host templates which don't
336 * limit the transfer size. Note this limit represents an absolute
337 * maximum, and may be over the transfer limits allowed for
338 * individual devices (e.g. 256 for SCSI-1)
339 */
340#define SCSI_DEFAULT_MAX_SECTORS 1024
341
342 /*
343 * True if this host adapter can make good use of linked commands.
344 * This will allow more than one command to be queued to a given
345 * unit on a given host. Set this to the maximum number of command
346 * blocks to be provided for each device. Set this to 1 for one
347 * command block per lun, 2 for two, etc. Do not set this to 0.
348 * You should make sure that the host adapter will do the right thing
349 * before you try setting this above 1.
350 */
351 short cmd_per_lun;
352
353 /*
354 * present contains counter indicating how many boards of this
355 * type were found when we did the scan.
356 */
357 unsigned char present;
358
359 /*
360 * true if this host adapter uses unchecked DMA onto an ISA bus.
361 */
362 unsigned unchecked_isa_dma:1;
363
364 /*
365 * true if this host adapter can make good use of clustering.
366 * I originally thought that if the tablesize was large that it
367 * was a waste of CPU cycles to prepare a cluster list, but
368 * it works out that the Buslogic is faster if you use a smaller
369 * number of segments (i.e. use clustering). I guess it is
370 * inefficient.
371 */
372 unsigned use_clustering:1;
373
374 /*
375 * True for emulated SCSI host adapters (e.g. ATAPI)
376 */
377 unsigned emulated:1;
378
379 /*
380 * True if the low-level driver performs its own reset-settle delays.
381 */
382 unsigned skip_settle_delay:1;
383
384 /*
385 * ordered write support
386 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 unsigned ordered_tag:1;
388
389 /*
390 * Countdown for host blocking with no commands outstanding
391 */
392 unsigned int max_host_blocked;
393
394 /*
395 * Default value for the blocking. If the queue is empty,
396 * host_blocked counts down in the request_fn until it restarts
397 * host operations as zero is reached.
398 *
399 * FIXME: This should probably be a value in the template
400 */
401#define SCSI_DEFAULT_HOST_BLOCKED 7
402
403 /*
404 * Pointer to the sysfs class properties for this host, NULL terminated.
405 */
406 struct class_device_attribute **shost_attrs;
407
408 /*
409 * Pointer to the SCSI device properties for this host, NULL terminated.
410 */
411 struct device_attribute **sdev_attrs;
412
413 /*
414 * List of hosts per template.
415 *
416 * This is only for use by scsi_module.c for legacy templates.
417 * For these access to it is synchronized implicitly by
418 * module_init/module_exit.
419 */
420 struct list_head legacy_hosts;
421};
422
423/*
Mike Andersond3301872005-06-16 11:12:38 -0700424 * shost state: If you alter this, you also need to alter scsi_sysfs.c
425 * (for the ascii descriptions) and the state model enforcer:
426 * scsi_host_set_state()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 */
Mike Andersond3301872005-06-16 11:12:38 -0700428enum scsi_host_state {
429 SHOST_CREATED = 1,
430 SHOST_RUNNING,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 SHOST_CANCEL,
Mike Andersond3301872005-06-16 11:12:38 -0700432 SHOST_DEL,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 SHOST_RECOVERY,
James Bottomley939647e2005-09-18 15:05:20 -0500434 SHOST_CANCEL_RECOVERY,
435 SHOST_DEL_RECOVERY,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436};
437
438struct Scsi_Host {
439 /*
440 * __devices is protected by the host_lock, but you should
441 * usually use scsi_device_lookup / shost_for_each_device
442 * to access it and don't care about locking yourself.
443 * In the rare case of beeing in irq context you can use
444 * their __ prefixed variants with the lock held. NEVER
445 * access this list directly from a driver.
446 */
447 struct list_head __devices;
448 struct list_head __targets;
449
450 struct scsi_host_cmd_pool *cmd_pool;
451 spinlock_t free_list_lock;
452 struct list_head free_list; /* backup store of cmd structs */
453 struct list_head starved_list;
454
455 spinlock_t default_lock;
456 spinlock_t *host_lock;
457
Arjan van de Ven0b950672006-01-11 13:16:10 +0100458 struct mutex scan_mutex;/* serialize scanning activity */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459
460 struct list_head eh_cmd_q;
461 struct task_struct * ehandler; /* Error recovery thread. */
Christoph Hellwig7dfdc9a2005-10-31 18:49:52 +0100462 struct completion * eh_action; /* Wait for specific actions on the
463 host. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 wait_queue_head_t host_wait;
465 struct scsi_host_template *hostt;
466 struct scsi_transport_template *transportt;
06f81ea2005-04-17 14:57:29 -0500467
468 /*
469 * The following two fields are protected with host_lock;
470 * however, eh routines can safely access during eh processing
471 * without acquiring the lock.
472 */
473 unsigned int host_busy; /* commands actually active on low-level */
474 unsigned int host_failed; /* commands that failed. */
Tejun Heoee7863b2006-05-15 20:57:20 +0900475 unsigned int host_eh_scheduled; /* EH scheduled without command */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476
477 unsigned short host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
478 int resetting; /* if set, it means that last_reset is a valid value */
479 unsigned long last_reset;
480
481 /*
482 * These three parameters can be used to allow for wide scsi,
483 * and for host adapters that support multiple busses
484 * The first two should be set to 1 more than the actual max id
485 * or lun (i.e. 8 for normal systems).
486 */
487 unsigned int max_id;
488 unsigned int max_lun;
489 unsigned int max_channel;
490
491 /*
492 * This is a unique identifier that must be assigned so that we
493 * have some way of identifying each detected host adapter properly
494 * and uniquely. For hosts that do not support more than one card
495 * in the system at one time, this does not need to be set. It is
496 * initialized to 0 in scsi_register.
497 */
498 unsigned int unique_id;
499
500 /*
501 * The maximum length of SCSI commands that this host can accept.
502 * Probably 12 for most host adapters, but could be 16 for others.
503 * For drivers that don't set this field, a value of 12 is
504 * assumed. I am leaving this as a number rather than a bit
505 * because you never know what subsequent SCSI standards might do
506 * (i.e. could there be a 20 byte or a 24-byte command a few years
507 * down the road?).
508 */
509 unsigned char max_cmd_len;
510
511 int this_id;
512 int can_queue;
513 short cmd_per_lun;
514 short unsigned int sg_tablesize;
515 short unsigned int max_sectors;
516 unsigned long dma_boundary;
517 /*
518 * Used to assign serial numbers to the cmds.
519 * Protected by the host lock.
520 */
521 unsigned long cmd_serial_number, cmd_pid;
522
523 unsigned unchecked_isa_dma:1;
524 unsigned use_clustering:1;
525 unsigned use_blk_tcq:1;
526
527 /*
528 * Host has requested that no further requests come through for the
529 * time being.
530 */
531 unsigned host_self_blocked:1;
532
533 /*
534 * Host uses correct SCSI ordering not PC ordering. The bit is
535 * set for the minority of drivers whose authors actually read
536 * the spec ;)
537 */
538 unsigned reverse_ordering:1;
539
540 /*
541 * ordered write support
542 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 unsigned ordered_tag:1;
544
James Smartd7a1bb02006-03-08 14:50:12 -0500545 /* task mgmt function in progress */
546 unsigned tmf_in_progress:1;
547
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 /*
549 * Optional work queue to be utilized by the transport
550 */
551 char work_q_name[KOBJ_NAME_LEN];
552 struct workqueue_struct *work_q;
553
554 /*
555 * Host has rejected a command because it was busy.
556 */
557 unsigned int host_blocked;
558
559 /*
560 * Value host_blocked counts down from
561 */
562 unsigned int max_host_blocked;
563
564 /* legacy crap */
565 unsigned long base;
566 unsigned long io_port;
567 unsigned char n_io_port;
568 unsigned char dma_channel;
569 unsigned int irq;
570
571
Mike Andersond3301872005-06-16 11:12:38 -0700572 enum scsi_host_state shost_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573
574 /* ldm bits */
575 struct device shost_gendev;
576 struct class_device shost_classdev;
577
578 /*
579 * List of hosts per template.
580 *
581 * This is only for use by scsi_module.c for legacy templates.
582 * For these access to it is synchronized implicitly by
583 * module_init/module_exit.
584 */
585 struct list_head sht_legacy_list;
586
587 /*
588 * Points to the transport data (if any) which is allocated
589 * separately
590 */
591 void *shost_data;
592
593 /*
594 * We should ensure that this is aligned, both for better performance
595 * and also because some compilers (m68k) don't automatically force
596 * alignment to a long boundary.
597 */
598 unsigned long hostdata[0] /* Used for storage of host specific stuff */
599 __attribute__ ((aligned (sizeof(unsigned long))));
600};
601
602#define class_to_shost(d) \
603 container_of(d, struct Scsi_Host, shost_classdev)
604
James Bottomley9ccfc752005-10-02 11:45:08 -0500605#define shost_printk(prefix, shost, fmt, a...) \
606 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
607
608
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609int scsi_is_host_device(const struct device *);
610
611static inline struct Scsi_Host *dev_to_shost(struct device *dev)
612{
613 while (!scsi_is_host_device(dev)) {
614 if (!dev->parent)
615 return NULL;
616 dev = dev->parent;
617 }
618 return container_of(dev, struct Scsi_Host, shost_gendev);
619}
620
James Bottomley939647e2005-09-18 15:05:20 -0500621static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
622{
623 return shost->shost_state == SHOST_RECOVERY ||
624 shost->shost_state == SHOST_CANCEL_RECOVERY ||
James Smartd7a1bb02006-03-08 14:50:12 -0500625 shost->shost_state == SHOST_DEL_RECOVERY ||
626 shost->tmf_in_progress;
James Bottomley939647e2005-09-18 15:05:20 -0500627}
628
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
630extern void scsi_flush_work(struct Scsi_Host *);
631
632extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
633extern int __must_check scsi_add_host(struct Scsi_Host *, struct device *);
634extern void scsi_scan_host(struct Scsi_Host *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635extern void scsi_rescan_device(struct device *);
636extern void scsi_remove_host(struct Scsi_Host *);
637extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
638extern void scsi_host_put(struct Scsi_Host *t);
639extern struct Scsi_Host *scsi_host_lookup(unsigned short);
Mike Andersond3301872005-06-16 11:12:38 -0700640extern const char *scsi_host_state_name(enum scsi_host_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641
642extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
643
644static inline void scsi_assign_lock(struct Scsi_Host *shost, spinlock_t *lock)
645{
646 shost->host_lock = lock;
647}
648
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649static inline struct device *scsi_get_device(struct Scsi_Host *shost)
650{
651 return shost->shost_gendev.parent;
652}
653
Mike Anderson82f29462005-06-16 11:14:33 -0700654/**
655 * scsi_host_scan_allowed - Is scanning of this host allowed
656 * @shost: Pointer to Scsi_Host.
657 **/
658static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
659{
660 return shost->shost_state == SHOST_RUNNING;
661}
662
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663extern void scsi_unblock_requests(struct Scsi_Host *);
664extern void scsi_block_requests(struct Scsi_Host *);
665
666struct class_container;
667/*
668 * These two functions are used to allocate and free a pseudo device
669 * which will connect to the host adapter itself rather than any
670 * physical device. You must deallocate when you are done with the
671 * thing. This physical pseudo-device isn't real and won't be available
672 * from any high-level drivers.
673 */
674extern void scsi_free_host_dev(struct scsi_device *);
675extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
676
677/* legacy interfaces */
678extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
679extern void scsi_unregister(struct Scsi_Host *);
James Bottomley47ba39e2005-07-30 11:39:53 -0500680extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681
682#endif /* _SCSI_SCSI_HOST_H */