Loading...
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 <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
46enum {
47 SCSI_QDEPTH_DEFAULT, /* default requested change, e.g. from sysfs */
48 SCSI_QDEPTH_QFULL, /* scsi-ml requested due to queue full */
49 SCSI_QDEPTH_RAMP_UP, /* scsi-ml requested due to threshold event */
50};
51
52struct scsi_host_template {
53 struct module *module;
54 const char *name;
55
56 /*
57 * Used to initialize old-style drivers. For new-style drivers
58 * just perform all work in your module initialization function.
59 *
60 * Status: OBSOLETE
61 */
62 int (* detect)(struct scsi_host_template *);
63
64 /*
65 * Used as unload callback for hosts with old-style drivers.
66 *
67 * Status: OBSOLETE
68 */
69 int (* release)(struct Scsi_Host *);
70
71 /*
72 * The info function will return whatever useful information the
73 * developer sees fit. If not provided, then the name field will
74 * be used instead.
75 *
76 * Status: OPTIONAL
77 */
78 const char *(* info)(struct Scsi_Host *);
79
80 /*
81 * Ioctl interface
82 *
83 * Status: OPTIONAL
84 */
85 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
86
87
88#ifdef CONFIG_COMPAT
89 /*
90 * Compat handler. Handle 32bit ABI.
91 * When unknown ioctl is passed return -ENOIOCTLCMD.
92 *
93 * Status: OPTIONAL
94 */
95 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
96#endif
97
98 /*
99 * The queuecommand function is used to queue up a scsi
100 * command block to the LLDD. When the driver finished
101 * processing the command the done callback is invoked.
102 *
103 * If queuecommand returns 0, then the HBA has accepted the
104 * command. The done() function must be called on the command
105 * when the driver has finished with it. (you may call done on the
106 * command before queuecommand returns, but in this case you
107 * *must* return 0 from queuecommand).
108 *
109 * Queuecommand may also reject the command, in which case it may
110 * not touch the command and must not call done() for it.
111 *
112 * There are two possible rejection returns:
113 *
114 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
115 * allow commands to other devices serviced by this host.
116 *
117 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
118 * host temporarily.
119 *
120 * For compatibility, any other non-zero return is treated the
121 * same as SCSI_MLQUEUE_HOST_BUSY.
122 *
123 * NOTE: "temporarily" means either until the next command for#
124 * this device/host completes, or a period of time determined by
125 * I/O pressure in the system if there are no other outstanding
126 * commands.
127 *
128 * STATUS: REQUIRED
129 */
130 int (* queuecommand)(struct Scsi_Host *, 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, 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 * This function is called when one or more partitions on the
330 * device reach beyond the end of the device.
331 *
332 * Status: OPTIONAL
333 */
334 void (*unlock_native_capacity)(struct scsi_device *);
335
336 /*
337 * Can be used to export driver statistics and other infos to the
338 * world outside the kernel ie. userspace and it also provides an
339 * interface to feed the driver with information.
340 *
341 * Status: OBSOLETE
342 */
343 int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int);
344
345 /*
346 * This is an optional routine that allows the transport to become
347 * involved when a scsi io timer fires. The return value tells the
348 * timer routine how to finish the io timeout handling:
349 * EH_HANDLED: I fixed the error, please complete the command
350 * EH_RESET_TIMER: I need more time, reset the timer and
351 * begin counting again
352 * EH_NOT_HANDLED Begin normal error recovery
353 *
354 * Status: OPTIONAL
355 */
356 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
357
358 /*
359 * Name of proc directory
360 */
361 const char *proc_name;
362
363 /*
364 * Used to store the procfs directory if a driver implements the
365 * proc_info method.
366 */
367 struct proc_dir_entry *proc_dir;
368
369 /*
370 * This determines if we will use a non-interrupt driven
371 * or an interrupt driven scheme. It is set to the maximum number
372 * of simultaneous commands a given host adapter will accept.
373 */
374 int can_queue;
375
376 /*
377 * In many instances, especially where disconnect / reconnect are
378 * supported, our host also has an ID on the SCSI bus. If this is
379 * the case, then it must be reserved. Please set this_id to -1 if
380 * your setup is in single initiator mode, and the host lacks an
381 * ID.
382 */
383 int this_id;
384
385 /*
386 * This determines the degree to which the host adapter is capable
387 * of scatter-gather.
388 */
389 unsigned short sg_tablesize;
390 unsigned short sg_prot_tablesize;
391
392 /*
393 * Set this if the host adapter has limitations beside segment count.
394 */
395 unsigned short max_sectors;
396
397 /*
398 * DMA scatter gather segment boundary limit. A segment crossing this
399 * boundary will be split in two.
400 */
401 unsigned long dma_boundary;
402
403 /*
404 * This specifies "machine infinity" for host templates which don't
405 * limit the transfer size. Note this limit represents an absolute
406 * maximum, and may be over the transfer limits allowed for
407 * individual devices (e.g. 256 for SCSI-1).
408 */
409#define SCSI_DEFAULT_MAX_SECTORS 1024
410
411 /*
412 * True if this host adapter can make good use of linked commands.
413 * This will allow more than one command to be queued to a given
414 * unit on a given host. Set this to the maximum number of command
415 * blocks to be provided for each device. Set this to 1 for one
416 * command block per lun, 2 for two, etc. Do not set this to 0.
417 * You should make sure that the host adapter will do the right thing
418 * before you try setting this above 1.
419 */
420 short cmd_per_lun;
421
422 /*
423 * present contains counter indicating how many boards of this
424 * type were found when we did the scan.
425 */
426 unsigned char present;
427
428 /*
429 * This specifies the mode that a LLD supports.
430 */
431 unsigned supported_mode:2;
432
433 /*
434 * True if this host adapter uses unchecked DMA onto an ISA bus.
435 */
436 unsigned unchecked_isa_dma:1;
437
438 /*
439 * True if this host adapter can make good use of clustering.
440 * I originally thought that if the tablesize was large that it
441 * was a waste of CPU cycles to prepare a cluster list, but
442 * it works out that the Buslogic is faster if you use a smaller
443 * number of segments (i.e. use clustering). I guess it is
444 * inefficient.
445 */
446 unsigned use_clustering:1;
447
448 /*
449 * True for emulated SCSI host adapters (e.g. ATAPI).
450 */
451 unsigned emulated:1;
452
453 /*
454 * True if the low-level driver performs its own reset-settle delays.
455 */
456 unsigned skip_settle_delay:1;
457
458 /*
459 * True if we are using ordered write support.
460 */
461 unsigned ordered_tag:1;
462
463 /*
464 * Countdown for host blocking with no commands outstanding.
465 */
466 unsigned int max_host_blocked;
467
468 /*
469 * Default value for the blocking. If the queue is empty,
470 * host_blocked counts down in the request_fn until it restarts
471 * host operations as zero is reached.
472 *
473 * FIXME: This should probably be a value in the template
474 */
475#define SCSI_DEFAULT_HOST_BLOCKED 7
476
477 /*
478 * Pointer to the sysfs class properties for this host, NULL terminated.
479 */
480 struct device_attribute **shost_attrs;
481
482 /*
483 * Pointer to the SCSI device properties for this host, NULL terminated.
484 */
485 struct device_attribute **sdev_attrs;
486
487 /*
488 * List of hosts per template.
489 *
490 * This is only for use by scsi_module.c for legacy templates.
491 * For these access to it is synchronized implicitly by
492 * module_init/module_exit.
493 */
494 struct list_head legacy_hosts;
495
496 /*
497 * Vendor Identifier associated with the host
498 *
499 * Note: When specifying vendor_id, be sure to read the
500 * Vendor Type and ID formatting requirements specified in
501 * scsi_netlink.h
502 */
503 u64 vendor_id;
504};
505
506/*
507 * Temporary #define for host lock push down. Can be removed when all
508 * drivers have been updated to take advantage of unlocked
509 * queuecommand.
510 *
511 */
512#define DEF_SCSI_QCMD(func_name) \
513 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
514 { \
515 unsigned long irq_flags; \
516 int rc; \
517 spin_lock_irqsave(shost->host_lock, irq_flags); \
518 scsi_cmd_get_serial(shost, cmd); \
519 rc = func_name##_lck (cmd, cmd->scsi_done); \
520 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
521 return rc; \
522 }
523
524
525/*
526 * shost state: If you alter this, you also need to alter scsi_sysfs.c
527 * (for the ascii descriptions) and the state model enforcer:
528 * scsi_host_set_state()
529 */
530enum scsi_host_state {
531 SHOST_CREATED = 1,
532 SHOST_RUNNING,
533 SHOST_CANCEL,
534 SHOST_DEL,
535 SHOST_RECOVERY,
536 SHOST_CANCEL_RECOVERY,
537 SHOST_DEL_RECOVERY,
538};
539
540struct Scsi_Host {
541 /*
542 * __devices is protected by the host_lock, but you should
543 * usually use scsi_device_lookup / shost_for_each_device
544 * to access it and don't care about locking yourself.
545 * In the rare case of beeing in irq context you can use
546 * their __ prefixed variants with the lock held. NEVER
547 * access this list directly from a driver.
548 */
549 struct list_head __devices;
550 struct list_head __targets;
551
552 struct scsi_host_cmd_pool *cmd_pool;
553 spinlock_t free_list_lock;
554 struct list_head free_list; /* backup store of cmd structs */
555 struct list_head starved_list;
556
557 spinlock_t default_lock;
558 spinlock_t *host_lock;
559
560 struct mutex scan_mutex;/* serialize scanning activity */
561
562 struct list_head eh_cmd_q;
563 struct task_struct * ehandler; /* Error recovery thread. */
564 struct completion * eh_action; /* Wait for specific actions on the
565 host. */
566 wait_queue_head_t host_wait;
567 struct scsi_host_template *hostt;
568 struct scsi_transport_template *transportt;
569
570 /*
571 * Area to keep a shared tag map (if needed, will be
572 * NULL if not).
573 */
574 struct blk_queue_tag *bqt;
575
576 /*
577 * The following two fields are protected with host_lock;
578 * however, eh routines can safely access during eh processing
579 * without acquiring the lock.
580 */
581 unsigned int host_busy; /* commands actually active on low-level */
582 unsigned int host_failed; /* commands that failed. */
583 unsigned int host_eh_scheduled; /* EH scheduled without command */
584
585 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
586 int resetting; /* if set, it means that last_reset is a valid value */
587 unsigned long last_reset;
588
589 /*
590 * These three parameters can be used to allow for wide scsi,
591 * and for host adapters that support multiple busses
592 * The first two should be set to 1 more than the actual max id
593 * or lun (i.e. 8 for normal systems).
594 */
595 unsigned int max_id;
596 unsigned int max_lun;
597 unsigned int max_channel;
598
599 /*
600 * This is a unique identifier that must be assigned so that we
601 * have some way of identifying each detected host adapter properly
602 * and uniquely. For hosts that do not support more than one card
603 * in the system at one time, this does not need to be set. It is
604 * initialized to 0 in scsi_register.
605 */
606 unsigned int unique_id;
607
608 /*
609 * The maximum length of SCSI commands that this host can accept.
610 * Probably 12 for most host adapters, but could be 16 for others.
611 * or 260 if the driver supports variable length cdbs.
612 * For drivers that don't set this field, a value of 12 is
613 * assumed.
614 */
615 unsigned short max_cmd_len;
616
617 int this_id;
618 int can_queue;
619 short cmd_per_lun;
620 short unsigned int sg_tablesize;
621 short unsigned int sg_prot_tablesize;
622 short unsigned int max_sectors;
623 unsigned long dma_boundary;
624 /*
625 * Used to assign serial numbers to the cmds.
626 * Protected by the host lock.
627 */
628 unsigned long cmd_serial_number;
629
630 unsigned active_mode:2;
631 unsigned unchecked_isa_dma:1;
632 unsigned use_clustering:1;
633 unsigned use_blk_tcq:1;
634
635 /*
636 * Host has requested that no further requests come through for the
637 * time being.
638 */
639 unsigned host_self_blocked:1;
640
641 /*
642 * Host uses correct SCSI ordering not PC ordering. The bit is
643 * set for the minority of drivers whose authors actually read
644 * the spec ;).
645 */
646 unsigned reverse_ordering:1;
647
648 /*
649 * Ordered write support
650 */
651 unsigned ordered_tag:1;
652
653 /* Task mgmt function in progress */
654 unsigned tmf_in_progress:1;
655
656 /* Asynchronous scan in progress */
657 unsigned async_scan:1;
658
659 /*
660 * Optional work queue to be utilized by the transport
661 */
662 char work_q_name[20];
663 struct workqueue_struct *work_q;
664
665 /*
666 * Host has rejected a command because it was busy.
667 */
668 unsigned int host_blocked;
669
670 /*
671 * Value host_blocked counts down from
672 */
673 unsigned int max_host_blocked;
674
675 /* Protection Information */
676 unsigned int prot_capabilities;
677 unsigned char prot_guard_type;
678
679 /*
680 * q used for scsi_tgt msgs, async events or any other requests that
681 * need to be processed in userspace
682 */
683 struct request_queue *uspace_req_q;
684
685 /* legacy crap */
686 unsigned long base;
687 unsigned long io_port;
688 unsigned char n_io_port;
689 unsigned char dma_channel;
690 unsigned int irq;
691
692
693 enum scsi_host_state shost_state;
694
695 /* ldm bits */
696 struct device shost_gendev, shost_dev;
697
698 /*
699 * List of hosts per template.
700 *
701 * This is only for use by scsi_module.c for legacy templates.
702 * For these access to it is synchronized implicitly by
703 * module_init/module_exit.
704 */
705 struct list_head sht_legacy_list;
706
707 /*
708 * Points to the transport data (if any) which is allocated
709 * separately
710 */
711 void *shost_data;
712
713 /*
714 * Points to the physical bus device we'd use to do DMA
715 * Needed just in case we have virtual hosts.
716 */
717 struct device *dma_dev;
718
719 /*
720 * We should ensure that this is aligned, both for better performance
721 * and also because some compilers (m68k) don't automatically force
722 * alignment to a long boundary.
723 */
724 unsigned long hostdata[0] /* Used for storage of host specific stuff */
725 __attribute__ ((aligned (sizeof(unsigned long))));
726};
727
728#define class_to_shost(d) \
729 container_of(d, struct Scsi_Host, shost_dev)
730
731#define shost_printk(prefix, shost, fmt, a...) \
732 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
733
734static inline void *shost_priv(struct Scsi_Host *shost)
735{
736 return (void *)shost->hostdata;
737}
738
739int scsi_is_host_device(const struct device *);
740
741static inline struct Scsi_Host *dev_to_shost(struct device *dev)
742{
743 while (!scsi_is_host_device(dev)) {
744 if (!dev->parent)
745 return NULL;
746 dev = dev->parent;
747 }
748 return container_of(dev, struct Scsi_Host, shost_gendev);
749}
750
751static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
752{
753 return shost->shost_state == SHOST_RECOVERY ||
754 shost->shost_state == SHOST_CANCEL_RECOVERY ||
755 shost->shost_state == SHOST_DEL_RECOVERY ||
756 shost->tmf_in_progress;
757}
758
759extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
760extern void scsi_flush_work(struct Scsi_Host *);
761
762extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
763extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
764 struct device *,
765 struct device *);
766extern void scsi_scan_host(struct Scsi_Host *);
767extern void scsi_rescan_device(struct device *);
768extern void scsi_remove_host(struct Scsi_Host *);
769extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
770extern void scsi_host_put(struct Scsi_Host *t);
771extern struct Scsi_Host *scsi_host_lookup(unsigned short);
772extern const char *scsi_host_state_name(enum scsi_host_state);
773extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *);
774
775extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
776
777static inline int __must_check scsi_add_host(struct Scsi_Host *host,
778 struct device *dev)
779{
780 return scsi_add_host_with_dma(host, dev, dev);
781}
782
783static inline struct device *scsi_get_device(struct Scsi_Host *shost)
784{
785 return shost->shost_gendev.parent;
786}
787
788/**
789 * scsi_host_scan_allowed - Is scanning of this host allowed
790 * @shost: Pointer to Scsi_Host.
791 **/
792static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
793{
794 return shost->shost_state == SHOST_RUNNING;
795}
796
797extern void scsi_unblock_requests(struct Scsi_Host *);
798extern void scsi_block_requests(struct Scsi_Host *);
799
800struct class_container;
801
802extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
803 void (*) (struct request_queue *));
804/*
805 * These two functions are used to allocate and free a pseudo device
806 * which will connect to the host adapter itself rather than any
807 * physical device. You must deallocate when you are done with the
808 * thing. This physical pseudo-device isn't real and won't be available
809 * from any high-level drivers.
810 */
811extern void scsi_free_host_dev(struct scsi_device *);
812extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
813
814/*
815 * DIF defines the exchange of protection information between
816 * initiator and SBC block device.
817 *
818 * DIX defines the exchange of protection information between OS and
819 * initiator.
820 */
821enum scsi_host_prot_capabilities {
822 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
823 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
824 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
825
826 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
827 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
828 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
829 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
830};
831
832/*
833 * SCSI hosts which support the Data Integrity Extensions must
834 * indicate their capabilities by setting the prot_capabilities using
835 * this call.
836 */
837static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
838{
839 shost->prot_capabilities = mask;
840}
841
842static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
843{
844 return shost->prot_capabilities;
845}
846
847static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
848{
849 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
850}
851
852static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
853{
854 static unsigned char cap[] = { 0,
855 SHOST_DIF_TYPE1_PROTECTION,
856 SHOST_DIF_TYPE2_PROTECTION,
857 SHOST_DIF_TYPE3_PROTECTION };
858
859 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
860}
861
862static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
863{
864#if defined(CONFIG_BLK_DEV_INTEGRITY)
865 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
866 SHOST_DIX_TYPE1_PROTECTION,
867 SHOST_DIX_TYPE2_PROTECTION,
868 SHOST_DIX_TYPE3_PROTECTION };
869
870 return shost->prot_capabilities & cap[target_type];
871#endif
872 return 0;
873}
874
875/*
876 * All DIX-capable initiators must support the T10-mandated CRC
877 * checksum. Controllers can optionally implement the IP checksum
878 * scheme which has much lower impact on system performance. Note
879 * that the main rationale for the checksum is to match integrity
880 * metadata with data. Detecting bit errors are a job for ECC memory
881 * and buses.
882 */
883
884enum scsi_host_guard_type {
885 SHOST_DIX_GUARD_CRC = 1 << 0,
886 SHOST_DIX_GUARD_IP = 1 << 1,
887};
888
889static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
890{
891 shost->prot_guard_type = type;
892}
893
894static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
895{
896 return shost->prot_guard_type;
897}
898
899/* legacy interfaces */
900extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
901extern void scsi_unregister(struct Scsi_Host *);
902extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
903
904#endif /* _SCSI_SCSI_HOST_H */
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _SCSI_SCSI_HOST_H
3#define _SCSI_SCSI_HOST_H
4
5#include <linux/device.h>
6#include <linux/list.h>
7#include <linux/types.h>
8#include <linux/workqueue.h>
9#include <linux/mutex.h>
10#include <linux/seq_file.h>
11#include <linux/blk-mq.h>
12#include <scsi/scsi.h>
13
14struct block_device;
15struct completion;
16struct module;
17struct scsi_cmnd;
18struct scsi_device;
19struct scsi_host_cmd_pool;
20struct scsi_target;
21struct Scsi_Host;
22struct scsi_host_cmd_pool;
23struct scsi_transport_template;
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 SG_CHUNK_SIZE
40
41#define MODE_UNKNOWN 0x00
42#define MODE_INITIATOR 0x01
43#define MODE_TARGET 0x02
44
45struct scsi_host_template {
46 struct module *module;
47 const char *name;
48
49 /*
50 * The info function will return whatever useful information the
51 * developer sees fit. If not provided, then the name field will
52 * be used instead.
53 *
54 * Status: OPTIONAL
55 */
56 const char *(* info)(struct Scsi_Host *);
57
58 /*
59 * Ioctl interface
60 *
61 * Status: OPTIONAL
62 */
63 int (*ioctl)(struct scsi_device *dev, unsigned int cmd,
64 void __user *arg);
65
66
67#ifdef CONFIG_COMPAT
68 /*
69 * Compat handler. Handle 32bit ABI.
70 * When unknown ioctl is passed return -ENOIOCTLCMD.
71 *
72 * Status: OPTIONAL
73 */
74 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,
75 void __user *arg);
76#endif
77
78 /*
79 * The queuecommand function is used to queue up a scsi
80 * command block to the LLDD. When the driver finished
81 * processing the command the done callback is invoked.
82 *
83 * If queuecommand returns 0, then the driver has accepted the
84 * command. It must also push it to the HBA if the scsi_cmnd
85 * flag SCMD_LAST is set, or if the driver does not implement
86 * commit_rqs. The done() function must be called on the command
87 * when the driver has finished with it. (you may call done on the
88 * command before queuecommand returns, but in this case you
89 * *must* return 0 from queuecommand).
90 *
91 * Queuecommand may also reject the command, in which case it may
92 * not touch the command and must not call done() for it.
93 *
94 * There are two possible rejection returns:
95 *
96 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
97 * allow commands to other devices serviced by this host.
98 *
99 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
100 * host temporarily.
101 *
102 * For compatibility, any other non-zero return is treated the
103 * same as SCSI_MLQUEUE_HOST_BUSY.
104 *
105 * NOTE: "temporarily" means either until the next command for#
106 * this device/host completes, or a period of time determined by
107 * I/O pressure in the system if there are no other outstanding
108 * commands.
109 *
110 * STATUS: REQUIRED
111 */
112 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
113
114 /*
115 * The commit_rqs function is used to trigger a hardware
116 * doorbell after some requests have been queued with
117 * queuecommand, when an error is encountered before sending
118 * the request with SCMD_LAST set.
119 *
120 * STATUS: OPTIONAL
121 */
122 void (*commit_rqs)(struct Scsi_Host *, u16);
123
124 /*
125 * This is an error handling strategy routine. You don't need to
126 * define one of these if you don't want to - there is a default
127 * routine that is present that should work in most cases. For those
128 * driver authors that have the inclination and ability to write their
129 * own strategy routine, this is where it is specified. Note - the
130 * strategy routine is *ALWAYS* run in the context of the kernel eh
131 * thread. Thus you are guaranteed to *NOT* be in an interrupt
132 * handler when you execute this, and you are also guaranteed to
133 * *NOT* have any other commands being queued while you are in the
134 * strategy routine. When you return from this function, operations
135 * return to normal.
136 *
137 * See scsi_error.c scsi_unjam_host for additional comments about
138 * what this function should and should not be attempting to do.
139 *
140 * Status: REQUIRED (at least one of them)
141 */
142 int (* eh_abort_handler)(struct scsi_cmnd *);
143 int (* eh_device_reset_handler)(struct scsi_cmnd *);
144 int (* eh_target_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 /*
149 * 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_change_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 /*
219 * 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 /*
243 * If a host has the ability to discover targets on its own instead
244 * of scanning the entire bus, it can fill in this function and
245 * call scsi_scan_host(). This function will be called periodically
246 * until it returns 1 with the scsi_host and the elapsed time of
247 * the scan in jiffies.
248 *
249 * Status: OPTIONAL
250 */
251 int (* scan_finished)(struct Scsi_Host *, unsigned long);
252
253 /*
254 * If the host wants to be called before the scan starts, but
255 * after the midlayer has set up ready for the scan, it can fill
256 * in this function.
257 *
258 * Status: OPTIONAL
259 */
260 void (* scan_start)(struct Scsi_Host *);
261
262 /*
263 * Fill in this function to allow the queue depth of this host
264 * to be changeable (on a per device basis). Returns either
265 * the current queue depth setting (may be different from what
266 * was passed in) or an error. An error should only be
267 * returned if the requested depth is legal but the driver was
268 * unable to set it. If the requested depth is illegal, the
269 * driver should set and return the closest legal queue depth.
270 *
271 * Status: OPTIONAL
272 */
273 int (* change_queue_depth)(struct scsi_device *, int);
274
275 /*
276 * This functions lets the driver expose the queue mapping
277 * to the block layer.
278 *
279 * Status: OPTIONAL
280 */
281 int (* map_queues)(struct Scsi_Host *shost);
282
283 /*
284 * This function determines the BIOS parameters for a given
285 * harddisk. These tend to be numbers that are made up by
286 * the host adapter. Parameters:
287 * size, device, list (heads, sectors, cylinders)
288 *
289 * Status: OPTIONAL
290 */
291 int (* bios_param)(struct scsi_device *, struct block_device *,
292 sector_t, int []);
293
294 /*
295 * This function is called when one or more partitions on the
296 * device reach beyond the end of the device.
297 *
298 * Status: OPTIONAL
299 */
300 void (*unlock_native_capacity)(struct scsi_device *);
301
302 /*
303 * Can be used to export driver statistics and other infos to the
304 * world outside the kernel ie. userspace and it also provides an
305 * interface to feed the driver with information.
306 *
307 * Status: OBSOLETE
308 */
309 int (*show_info)(struct seq_file *, struct Scsi_Host *);
310 int (*write_info)(struct Scsi_Host *, char *, int);
311
312 /*
313 * This is an optional routine that allows the transport to become
314 * involved when a scsi io timer fires. The return value tells the
315 * timer routine how to finish the io timeout handling.
316 *
317 * Status: OPTIONAL
318 */
319 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
320
321 /* This is an optional routine that allows transport to initiate
322 * LLD adapter or firmware reset using sysfs attribute.
323 *
324 * Return values: 0 on success, -ve value on failure.
325 *
326 * Status: OPTIONAL
327 */
328
329 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
330#define SCSI_ADAPTER_RESET 1
331#define SCSI_FIRMWARE_RESET 2
332
333
334 /*
335 * Name of proc directory
336 */
337 const char *proc_name;
338
339 /*
340 * Used to store the procfs directory if a driver implements the
341 * show_info method.
342 */
343 struct proc_dir_entry *proc_dir;
344
345 /*
346 * This determines if we will use a non-interrupt driven
347 * or an interrupt driven scheme. It is set to the maximum number
348 * of simultaneous commands a given host adapter will accept.
349 */
350 int can_queue;
351
352 /*
353 * In many instances, especially where disconnect / reconnect are
354 * supported, our host also has an ID on the SCSI bus. If this is
355 * the case, then it must be reserved. Please set this_id to -1 if
356 * your setup is in single initiator mode, and the host lacks an
357 * ID.
358 */
359 int this_id;
360
361 /*
362 * This determines the degree to which the host adapter is capable
363 * of scatter-gather.
364 */
365 unsigned short sg_tablesize;
366 unsigned short sg_prot_tablesize;
367
368 /*
369 * Set this if the host adapter has limitations beside segment count.
370 */
371 unsigned int max_sectors;
372
373 /*
374 * Maximum size in bytes of a single segment.
375 */
376 unsigned int max_segment_size;
377
378 /*
379 * DMA scatter gather segment boundary limit. A segment crossing this
380 * boundary will be split in two.
381 */
382 unsigned long dma_boundary;
383
384 unsigned long virt_boundary_mask;
385
386 /*
387 * This specifies "machine infinity" for host templates which don't
388 * limit the transfer size. Note this limit represents an absolute
389 * maximum, and may be over the transfer limits allowed for
390 * individual devices (e.g. 256 for SCSI-1).
391 */
392#define SCSI_DEFAULT_MAX_SECTORS 1024
393
394 /*
395 * True if this host adapter can make good use of linked commands.
396 * This will allow more than one command to be queued to a given
397 * unit on a given host. Set this to the maximum number of command
398 * blocks to be provided for each device. Set this to 1 for one
399 * command block per lun, 2 for two, etc. Do not set this to 0.
400 * You should make sure that the host adapter will do the right thing
401 * before you try setting this above 1.
402 */
403 short cmd_per_lun;
404
405 /*
406 * present contains counter indicating how many boards of this
407 * type were found when we did the scan.
408 */
409 unsigned char present;
410
411 /* If use block layer to manage tags, this is tag allocation policy */
412 int tag_alloc_policy;
413
414 /*
415 * Track QUEUE_FULL events and reduce queue depth on demand.
416 */
417 unsigned track_queue_depth:1;
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 for emulated SCSI host adapters (e.g. ATAPI).
431 */
432 unsigned emulated:1;
433
434 /*
435 * True if the low-level driver performs its own reset-settle delays.
436 */
437 unsigned skip_settle_delay:1;
438
439 /* True if the controller does not support WRITE SAME */
440 unsigned no_write_same:1;
441
442 /* True if the low-level driver supports blk-mq only */
443 unsigned force_blk_mq:1;
444
445 /*
446 * Countdown for host blocking with no commands outstanding.
447 */
448 unsigned int max_host_blocked;
449
450 /*
451 * Default value for the blocking. If the queue is empty,
452 * host_blocked counts down in the request_fn until it restarts
453 * host operations as zero is reached.
454 *
455 * FIXME: This should probably be a value in the template
456 */
457#define SCSI_DEFAULT_HOST_BLOCKED 7
458
459 /*
460 * Pointer to the sysfs class properties for this host, NULL terminated.
461 */
462 struct device_attribute **shost_attrs;
463
464 /*
465 * Pointer to the SCSI device properties for this host, NULL terminated.
466 */
467 struct device_attribute **sdev_attrs;
468
469 /*
470 * Pointer to the SCSI device attribute groups for this host,
471 * NULL terminated.
472 */
473 const struct attribute_group **sdev_groups;
474
475 /*
476 * Vendor Identifier associated with the host
477 *
478 * Note: When specifying vendor_id, be sure to read the
479 * Vendor Type and ID formatting requirements specified in
480 * scsi_netlink.h
481 */
482 u64 vendor_id;
483
484 /*
485 * Additional per-command data allocated for the driver.
486 */
487 unsigned int cmd_size;
488 struct scsi_host_cmd_pool *cmd_pool;
489};
490
491/*
492 * Temporary #define for host lock push down. Can be removed when all
493 * drivers have been updated to take advantage of unlocked
494 * queuecommand.
495 *
496 */
497#define DEF_SCSI_QCMD(func_name) \
498 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
499 { \
500 unsigned long irq_flags; \
501 int rc; \
502 spin_lock_irqsave(shost->host_lock, irq_flags); \
503 rc = func_name##_lck (cmd, cmd->scsi_done); \
504 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
505 return rc; \
506 }
507
508
509/*
510 * shost state: If you alter this, you also need to alter scsi_sysfs.c
511 * (for the ascii descriptions) and the state model enforcer:
512 * scsi_host_set_state()
513 */
514enum scsi_host_state {
515 SHOST_CREATED = 1,
516 SHOST_RUNNING,
517 SHOST_CANCEL,
518 SHOST_DEL,
519 SHOST_RECOVERY,
520 SHOST_CANCEL_RECOVERY,
521 SHOST_DEL_RECOVERY,
522};
523
524struct Scsi_Host {
525 /*
526 * __devices is protected by the host_lock, but you should
527 * usually use scsi_device_lookup / shost_for_each_device
528 * to access it and don't care about locking yourself.
529 * In the rare case of being in irq context you can use
530 * their __ prefixed variants with the lock held. NEVER
531 * access this list directly from a driver.
532 */
533 struct list_head __devices;
534 struct list_head __targets;
535
536 struct list_head starved_list;
537
538 spinlock_t default_lock;
539 spinlock_t *host_lock;
540
541 struct mutex scan_mutex;/* serialize scanning activity */
542
543 struct list_head eh_cmd_q;
544 struct task_struct * ehandler; /* Error recovery thread. */
545 struct completion * eh_action; /* Wait for specific actions on the
546 host. */
547 wait_queue_head_t host_wait;
548 struct scsi_host_template *hostt;
549 struct scsi_transport_template *transportt;
550
551 /* Area to keep a shared tag map */
552 struct blk_mq_tag_set tag_set;
553
554 atomic_t host_busy; /* commands actually active on low-level */
555 atomic_t host_blocked;
556
557 unsigned int host_failed; /* commands that failed.
558 protected by host_lock */
559 unsigned int host_eh_scheduled; /* EH scheduled without command */
560
561 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
562
563 /* next two fields are used to bound the time spent in error handling */
564 int eh_deadline;
565 unsigned long last_reset;
566
567
568 /*
569 * These three parameters can be used to allow for wide scsi,
570 * and for host adapters that support multiple busses
571 * The last two should be set to 1 more than the actual max id
572 * or lun (e.g. 8 for SCSI parallel systems).
573 */
574 unsigned int max_channel;
575 unsigned int max_id;
576 u64 max_lun;
577
578 /*
579 * This is a unique identifier that must be assigned so that we
580 * have some way of identifying each detected host adapter properly
581 * and uniquely. For hosts that do not support more than one card
582 * in the system at one time, this does not need to be set. It is
583 * initialized to 0 in scsi_register.
584 */
585 unsigned int unique_id;
586
587 /*
588 * The maximum length of SCSI commands that this host can accept.
589 * Probably 12 for most host adapters, but could be 16 for others.
590 * or 260 if the driver supports variable length cdbs.
591 * For drivers that don't set this field, a value of 12 is
592 * assumed.
593 */
594 unsigned short max_cmd_len;
595
596 int this_id;
597 int can_queue;
598 short cmd_per_lun;
599 short unsigned int sg_tablesize;
600 short unsigned int sg_prot_tablesize;
601 unsigned int max_sectors;
602 unsigned int max_segment_size;
603 unsigned long dma_boundary;
604 unsigned long virt_boundary_mask;
605 /*
606 * In scsi-mq mode, the number of hardware queues supported by the LLD.
607 *
608 * Note: it is assumed that each hardware queue has a queue depth of
609 * can_queue. In other words, the total queue depth per host
610 * is nr_hw_queues * can_queue.
611 */
612 unsigned nr_hw_queues;
613 unsigned active_mode:2;
614 unsigned unchecked_isa_dma:1;
615
616 /*
617 * Host has requested that no further requests come through for the
618 * time being.
619 */
620 unsigned host_self_blocked:1;
621
622 /*
623 * Host uses correct SCSI ordering not PC ordering. The bit is
624 * set for the minority of drivers whose authors actually read
625 * the spec ;).
626 */
627 unsigned reverse_ordering:1;
628
629 /* Task mgmt function in progress */
630 unsigned tmf_in_progress:1;
631
632 /* Asynchronous scan in progress */
633 unsigned async_scan:1;
634
635 /* Don't resume host in EH */
636 unsigned eh_noresume:1;
637
638 /* The controller does not support WRITE SAME */
639 unsigned no_write_same:1;
640
641 unsigned use_cmd_list:1;
642
643 /* Host responded with short (<36 bytes) INQUIRY result */
644 unsigned short_inquiry:1;
645
646 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
647 unsigned no_scsi2_lun_in_cdb:1;
648
649 /*
650 * Optional work queue to be utilized by the transport
651 */
652 char work_q_name[20];
653 struct workqueue_struct *work_q;
654
655 /*
656 * Task management function work queue
657 */
658 struct workqueue_struct *tmf_work_q;
659
660 /*
661 * Value host_blocked counts down from
662 */
663 unsigned int max_host_blocked;
664
665 /* Protection Information */
666 unsigned int prot_capabilities;
667 unsigned char prot_guard_type;
668
669 /* legacy crap */
670 unsigned long base;
671 unsigned long io_port;
672 unsigned char n_io_port;
673 unsigned char dma_channel;
674 unsigned int irq;
675
676
677 enum scsi_host_state shost_state;
678
679 /* ldm bits */
680 struct device shost_gendev, shost_dev;
681
682 /*
683 * Points to the transport data (if any) which is allocated
684 * separately
685 */
686 void *shost_data;
687
688 /*
689 * Points to the physical bus device we'd use to do DMA
690 * Needed just in case we have virtual hosts.
691 */
692 struct device *dma_dev;
693
694 /*
695 * We should ensure that this is aligned, both for better performance
696 * and also because some compilers (m68k) don't automatically force
697 * alignment to a long boundary.
698 */
699 unsigned long hostdata[0] /* Used for storage of host specific stuff */
700 __attribute__ ((aligned (sizeof(unsigned long))));
701};
702
703#define class_to_shost(d) \
704 container_of(d, struct Scsi_Host, shost_dev)
705
706#define shost_printk(prefix, shost, fmt, a...) \
707 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
708
709static inline void *shost_priv(struct Scsi_Host *shost)
710{
711 return (void *)shost->hostdata;
712}
713
714int scsi_is_host_device(const struct device *);
715
716static inline struct Scsi_Host *dev_to_shost(struct device *dev)
717{
718 while (!scsi_is_host_device(dev)) {
719 if (!dev->parent)
720 return NULL;
721 dev = dev->parent;
722 }
723 return container_of(dev, struct Scsi_Host, shost_gendev);
724}
725
726static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
727{
728 return shost->shost_state == SHOST_RECOVERY ||
729 shost->shost_state == SHOST_CANCEL_RECOVERY ||
730 shost->shost_state == SHOST_DEL_RECOVERY ||
731 shost->tmf_in_progress;
732}
733
734extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
735extern void scsi_flush_work(struct Scsi_Host *);
736
737extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
738extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
739 struct device *,
740 struct device *);
741extern void scsi_scan_host(struct Scsi_Host *);
742extern void scsi_rescan_device(struct device *);
743extern void scsi_remove_host(struct Scsi_Host *);
744extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
745extern int scsi_host_busy(struct Scsi_Host *shost);
746extern void scsi_host_put(struct Scsi_Host *t);
747extern struct Scsi_Host *scsi_host_lookup(unsigned short);
748extern const char *scsi_host_state_name(enum scsi_host_state);
749
750static inline int __must_check scsi_add_host(struct Scsi_Host *host,
751 struct device *dev)
752{
753 return scsi_add_host_with_dma(host, dev, dev);
754}
755
756static inline struct device *scsi_get_device(struct Scsi_Host *shost)
757{
758 return shost->shost_gendev.parent;
759}
760
761/**
762 * scsi_host_scan_allowed - Is scanning of this host allowed
763 * @shost: Pointer to Scsi_Host.
764 **/
765static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
766{
767 return shost->shost_state == SHOST_RUNNING ||
768 shost->shost_state == SHOST_RECOVERY;
769}
770
771extern void scsi_unblock_requests(struct Scsi_Host *);
772extern void scsi_block_requests(struct Scsi_Host *);
773
774struct class_container;
775
776/*
777 * These two functions are used to allocate and free a pseudo device
778 * which will connect to the host adapter itself rather than any
779 * physical device. You must deallocate when you are done with the
780 * thing. This physical pseudo-device isn't real and won't be available
781 * from any high-level drivers.
782 */
783extern void scsi_free_host_dev(struct scsi_device *);
784extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
785
786/*
787 * DIF defines the exchange of protection information between
788 * initiator and SBC block device.
789 *
790 * DIX defines the exchange of protection information between OS and
791 * initiator.
792 */
793enum scsi_host_prot_capabilities {
794 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
795 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
796 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
797
798 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
799 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
800 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
801 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
802};
803
804/*
805 * SCSI hosts which support the Data Integrity Extensions must
806 * indicate their capabilities by setting the prot_capabilities using
807 * this call.
808 */
809static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
810{
811 shost->prot_capabilities = mask;
812}
813
814static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
815{
816 return shost->prot_capabilities;
817}
818
819static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
820{
821 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
822}
823
824static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
825{
826 static unsigned char cap[] = { 0,
827 SHOST_DIF_TYPE1_PROTECTION,
828 SHOST_DIF_TYPE2_PROTECTION,
829 SHOST_DIF_TYPE3_PROTECTION };
830
831 if (target_type >= ARRAY_SIZE(cap))
832 return 0;
833
834 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
835}
836
837static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
838{
839#if defined(CONFIG_BLK_DEV_INTEGRITY)
840 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
841 SHOST_DIX_TYPE1_PROTECTION,
842 SHOST_DIX_TYPE2_PROTECTION,
843 SHOST_DIX_TYPE3_PROTECTION };
844
845 if (target_type >= ARRAY_SIZE(cap))
846 return 0;
847
848 return shost->prot_capabilities & cap[target_type];
849#endif
850 return 0;
851}
852
853/*
854 * All DIX-capable initiators must support the T10-mandated CRC
855 * checksum. Controllers can optionally implement the IP checksum
856 * scheme which has much lower impact on system performance. Note
857 * that the main rationale for the checksum is to match integrity
858 * metadata with data. Detecting bit errors are a job for ECC memory
859 * and buses.
860 */
861
862enum scsi_host_guard_type {
863 SHOST_DIX_GUARD_CRC = 1 << 0,
864 SHOST_DIX_GUARD_IP = 1 << 1,
865};
866
867static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
868{
869 shost->prot_guard_type = type;
870}
871
872static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
873{
874 return shost->prot_guard_type;
875}
876
877extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
878
879#endif /* _SCSI_SCSI_HOST_H */