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
14 struct block_device;
15 struct completion;
16 struct module;
17 struct scsi_cmnd;
18 struct scsi_device;
19 struct scsi_target;
20 struct Scsi_Host;
21 struct scsi_transport_template;
22
23
24 #define SG_ALL SG_CHUNK_SIZE
25
26 #define MODE_UNKNOWN 0x00
27 #define MODE_INITIATOR 0x01
28 #define MODE_TARGET 0x02
29
30 /**
31 * enum scsi_timeout_action - How to handle a command that timed out.
32 * @SCSI_EH_DONE: The command has already been completed.
33 * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion.
34 * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command.
35 */
36 enum scsi_timeout_action {
37 SCSI_EH_DONE,
38 SCSI_EH_RESET_TIMER,
39 SCSI_EH_NOT_HANDLED,
40 };
41
42 struct scsi_host_template {
43 /*
44 * Put fields referenced in IO submission path together in
45 * same cacheline
46 */
47
48 /*
49 * Additional per-command data allocated for the driver.
50 */
51 unsigned int cmd_size;
52
53 /*
54 * The queuecommand function is used to queue up a scsi
55 * command block to the LLDD. When the driver finished
56 * processing the command the done callback is invoked.
57 *
58 * If queuecommand returns 0, then the driver has accepted the
59 * command. It must also push it to the HBA if the scsi_cmnd
60 * flag SCMD_LAST is set, or if the driver does not implement
61 * commit_rqs. The done() function must be called on the command
62 * when the driver has finished with it. (you may call done on the
63 * command before queuecommand returns, but in this case you
64 * *must* return 0 from queuecommand).
65 *
66 * Queuecommand may also reject the command, in which case it may
67 * not touch the command and must not call done() for it.
68 *
69 * There are two possible rejection returns:
70 *
71 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
72 * allow commands to other devices serviced by this host.
73 *
74 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
75 * host temporarily.
76 *
77 * For compatibility, any other non-zero return is treated the
78 * same as SCSI_MLQUEUE_HOST_BUSY.
79 *
80 * NOTE: "temporarily" means either until the next command for#
81 * this device/host completes, or a period of time determined by
82 * I/O pressure in the system if there are no other outstanding
83 * commands.
84 *
85 * STATUS: REQUIRED
86 */
87 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
88
89 /*
90 * The commit_rqs function is used to trigger a hardware
91 * doorbell after some requests have been queued with
92 * queuecommand, when an error is encountered before sending
93 * the request with SCMD_LAST set.
94 *
95 * STATUS: OPTIONAL
96 */
97 void (*commit_rqs)(struct Scsi_Host *, u16);
98
99 struct module *module;
100 const char *name;
101
102 /*
103 * The info function will return whatever useful information the
104 * developer sees fit. If not provided, then the name field will
105 * be used instead.
106 *
107 * Status: OPTIONAL
108 */
109 const char *(*info)(struct Scsi_Host *);
110
111 /*
112 * Ioctl interface
113 *
114 * Status: OPTIONAL
115 */
116 int (*ioctl)(struct scsi_device *dev, unsigned int cmd,
117 void __user *arg);
118
119
120 #ifdef CONFIG_COMPAT
121 /*
122 * Compat handler. Handle 32bit ABI.
123 * When unknown ioctl is passed return -ENOIOCTLCMD.
124 *
125 * Status: OPTIONAL
126 */
127 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,
128 void __user *arg);
129 #endif
130
131 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
132 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
133
134 /*
135 * This is an error handling strategy routine. You don't need to
136 * define one of these if you don't want to - there is a default
137 * routine that is present that should work in most cases. For those
138 * driver authors that have the inclination and ability to write their
139 * own strategy routine, this is where it is specified. Note - the
140 * strategy routine is *ALWAYS* run in the context of the kernel eh
141 * thread. Thus you are guaranteed to *NOT* be in an interrupt
142 * handler when you execute this, and you are also guaranteed to
143 * *NOT* have any other commands being queued while you are in the
144 * strategy routine. When you return from this function, operations
145 * return to normal.
146 *
147 * See scsi_error.c scsi_unjam_host for additional comments about
148 * what this function should and should not be attempting to do.
149 *
150 * Status: REQUIRED (at least one of them)
151 */
152 int (* eh_abort_handler)(struct scsi_cmnd *);
153 int (* eh_device_reset_handler)(struct scsi_cmnd *);
154 int (* eh_target_reset_handler)(struct scsi_cmnd *);
155 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
156 int (* eh_host_reset_handler)(struct scsi_cmnd *);
157
158 /*
159 * Before the mid layer attempts to scan for a new device where none
160 * currently exists, it will call this entry in your driver. Should
161 * your driver need to allocate any structs or perform any other init
162 * items in order to send commands to a currently unused target/lun
163 * combo, then this is where you can perform those allocations. This
164 * is specifically so that drivers won't have to perform any kind of
165 * "is this a new device" checks in their queuecommand routine,
166 * thereby making the hot path a bit quicker.
167 *
168 * Return values: 0 on success, non-0 on failure
169 *
170 * Deallocation: If we didn't find any devices at this ID, you will
171 * get an immediate call to slave_destroy(). If we find something
172 * here then you will get a call to slave_configure(), then the
173 * device will be used for however long it is kept around, then when
174 * the device is removed from the system (or * possibly at reboot
175 * time), you will then get a call to slave_destroy(). This is
176 * assuming you implement slave_configure and slave_destroy.
177 * However, if you allocate memory and hang it off the device struct,
178 * then you must implement the slave_destroy() routine at a minimum
179 * in order to avoid leaking memory
180 * each time a device is tore down.
181 *
182 * Status: OPTIONAL
183 */
184 int (* slave_alloc)(struct scsi_device *);
185
186 /*
187 * Once the device has responded to an INQUIRY and we know the
188 * device is online, we call into the low level driver with the
189 * struct scsi_device *. If the low level device driver implements
190 * this function, it *must* perform the task of setting the queue
191 * depth on the device. All other tasks are optional and depend
192 * on what the driver supports and various implementation details.
193 *
194 * Things currently recommended to be handled at this time include:
195 *
196 * 1. Setting the device queue depth. Proper setting of this is
197 * described in the comments for scsi_change_queue_depth.
198 * 2. Determining if the device supports the various synchronous
199 * negotiation protocols. The device struct will already have
200 * responded to INQUIRY and the results of the standard items
201 * will have been shoved into the various device flag bits, eg.
202 * device->sdtr will be true if the device supports SDTR messages.
203 * 3. Allocating command structs that the device will need.
204 * 4. Setting the default timeout on this device (if needed).
205 * 5. Anything else the low level driver might want to do on a device
206 * specific setup basis...
207 * 6. Return 0 on success, non-0 on error. The device will be marked
208 * as offline on error so that no access will occur. If you return
209 * non-0, your slave_destroy routine will never get called for this
210 * device, so don't leave any loose memory hanging around, clean
211 * up after yourself before returning non-0
212 *
213 * Status: OPTIONAL
214 */
215 int (* slave_configure)(struct scsi_device *);
216
217 /*
218 * Immediately prior to deallocating the device and after all activity
219 * has ceased the mid layer calls this point so that the low level
220 * driver may completely detach itself from the scsi device and vice
221 * versa. The low level driver is responsible for freeing any memory
222 * it allocated in the slave_alloc or slave_configure calls.
223 *
224 * Status: OPTIONAL
225 */
226 void (* slave_destroy)(struct scsi_device *);
227
228 /*
229 * Before the mid layer attempts to scan for a new device attached
230 * to a target where no target currently exists, it will call this
231 * entry in your driver. Should your driver need to allocate any
232 * structs or perform any other init items in order to send commands
233 * to a currently unused target, then this is where you can perform
234 * those allocations.
235 *
236 * Return values: 0 on success, non-0 on failure
237 *
238 * Status: OPTIONAL
239 */
240 int (* target_alloc)(struct scsi_target *);
241
242 /*
243 * Immediately prior to deallocating the target structure, and
244 * after all activity to attached scsi devices has ceased, the
245 * midlayer calls this point so that the driver may deallocate
246 * and terminate any references to the target.
247 *
248 * Status: OPTIONAL
249 */
250 void (* target_destroy)(struct scsi_target *);
251
252 /*
253 * If a host has the ability to discover targets on its own instead
254 * of scanning the entire bus, it can fill in this function and
255 * call scsi_scan_host(). This function will be called periodically
256 * until it returns 1 with the scsi_host and the elapsed time of
257 * the scan in jiffies.
258 *
259 * Status: OPTIONAL
260 */
261 int (* scan_finished)(struct Scsi_Host *, unsigned long);
262
263 /*
264 * If the host wants to be called before the scan starts, but
265 * after the midlayer has set up ready for the scan, it can fill
266 * in this function.
267 *
268 * Status: OPTIONAL
269 */
270 void (* scan_start)(struct Scsi_Host *);
271
272 /*
273 * Fill in this function to allow the queue depth of this host
274 * to be changeable (on a per device basis). Returns either
275 * the current queue depth setting (may be different from what
276 * was passed in) or an error. An error should only be
277 * returned if the requested depth is legal but the driver was
278 * unable to set it. If the requested depth is illegal, the
279 * driver should set and return the closest legal queue depth.
280 *
281 * Status: OPTIONAL
282 */
283 int (* change_queue_depth)(struct scsi_device *, int);
284
285 /*
286 * This functions lets the driver expose the queue mapping
287 * to the block layer.
288 *
289 * Status: OPTIONAL
290 */
291 void (* map_queues)(struct Scsi_Host *shost);
292
293 /*
294 * SCSI interface of blk_poll - poll for IO completions.
295 * Only applicable if SCSI LLD exposes multiple h/w queues.
296 *
297 * Return value: Number of completed entries found.
298 *
299 * Status: OPTIONAL
300 */
301 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num);
302
303 /*
304 * Check if scatterlists need to be padded for DMA draining.
305 *
306 * Status: OPTIONAL
307 */
308 bool (* dma_need_drain)(struct request *rq);
309
310 /*
311 * This function determines the BIOS parameters for a given
312 * harddisk. These tend to be numbers that are made up by
313 * the host adapter. Parameters:
314 * size, device, list (heads, sectors, cylinders)
315 *
316 * Status: OPTIONAL
317 */
318 int (* bios_param)(struct scsi_device *, struct block_device *,
319 sector_t, int []);
320
321 /*
322 * This function is called when one or more partitions on the
323 * device reach beyond the end of the device.
324 *
325 * Status: OPTIONAL
326 */
327 void (*unlock_native_capacity)(struct scsi_device *);
328
329 /*
330 * Can be used to export driver statistics and other infos to the
331 * world outside the kernel ie. userspace and it also provides an
332 * interface to feed the driver with information.
333 *
334 * Status: OBSOLETE
335 */
336 int (*show_info)(struct seq_file *, struct Scsi_Host *);
337 int (*write_info)(struct Scsi_Host *, char *, int);
338
339 /*
340 * This is an optional routine that allows the transport to become
341 * involved when a scsi io timer fires. The return value tells the
342 * timer routine how to finish the io timeout handling.
343 *
344 * Status: OPTIONAL
345 */
346 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *);
347 /*
348 * Optional routine that allows the transport to decide if a cmd
349 * is retryable. Return true if the transport is in a state the
350 * cmd should be retried on.
351 */
352 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd);
353
354 /* This is an optional routine that allows transport to initiate
355 * LLD adapter or firmware reset using sysfs attribute.
356 *
357 * Return values: 0 on success, -ve value on failure.
358 *
359 * Status: OPTIONAL
360 */
361
362 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
363 #define SCSI_ADAPTER_RESET 1
364 #define SCSI_FIRMWARE_RESET 2
365
366
367 /*
368 * Name of proc directory
369 */
370 const char *proc_name;
371
372 /*
373 * This determines if we will use a non-interrupt driven
374 * or an interrupt driven scheme. It is set to the maximum number
375 * of simultaneous commands a single hw queue in HBA will accept.
376 */
377 int can_queue;
378
379 /*
380 * In many instances, especially where disconnect / reconnect are
381 * supported, our host also has an ID on the SCSI bus. If this is
382 * the case, then it must be reserved. Please set this_id to -1 if
383 * your setup is in single initiator mode, and the host lacks an
384 * ID.
385 */
386 int this_id;
387
388 /*
389 * This determines the degree to which the host adapter is capable
390 * of scatter-gather.
391 */
392 unsigned short sg_tablesize;
393 unsigned short sg_prot_tablesize;
394
395 /*
396 * Set this if the host adapter has limitations beside segment count.
397 */
398 unsigned int max_sectors;
399
400 /*
401 * Maximum size in bytes of a single segment.
402 */
403 unsigned int max_segment_size;
404
405 /*
406 * DMA scatter gather segment boundary limit. A segment crossing this
407 * boundary will be split in two.
408 */
409 unsigned long dma_boundary;
410
411 unsigned long virt_boundary_mask;
412
413 /*
414 * This specifies "machine infinity" for host templates which don't
415 * limit the transfer size. Note this limit represents an absolute
416 * maximum, and may be over the transfer limits allowed for
417 * individual devices (e.g. 256 for SCSI-1).
418 */
419 #define SCSI_DEFAULT_MAX_SECTORS 1024
420
421 /*
422 * True if this host adapter can make good use of linked commands.
423 * This will allow more than one command to be queued to a given
424 * unit on a given host. Set this to the maximum number of command
425 * blocks to be provided for each device. Set this to 1 for one
426 * command block per lun, 2 for two, etc. Do not set this to 0.
427 * You should make sure that the host adapter will do the right thing
428 * before you try setting this above 1.
429 */
430 short cmd_per_lun;
431
432 /* If use block layer to manage tags, this is tag allocation policy */
433 int tag_alloc_policy;
434
435 /*
436 * Track QUEUE_FULL events and reduce queue depth on demand.
437 */
438 unsigned track_queue_depth:1;
439
440 /*
441 * This specifies the mode that a LLD supports.
442 */
443 unsigned supported_mode:2;
444
445 /*
446 * True for emulated SCSI host adapters (e.g. ATAPI).
447 */
448 unsigned emulated:1;
449
450 /*
451 * True if the low-level driver performs its own reset-settle delays.
452 */
453 unsigned skip_settle_delay:1;
454
455 /* True if the controller does not support WRITE SAME */
456 unsigned no_write_same:1;
457
458 /* True if the host uses host-wide tagspace */
459 unsigned host_tagset:1;
460
461 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
462 unsigned queuecommand_may_block:1;
463
464 /*
465 * Countdown for host blocking with no commands outstanding.
466 */
467 unsigned int max_host_blocked;
468
469 /*
470 * Default value for the blocking. If the queue is empty,
471 * host_blocked counts down in the request_fn until it restarts
472 * host operations as zero is reached.
473 *
474 * FIXME: This should probably be a value in the template
475 */
476 #define SCSI_DEFAULT_HOST_BLOCKED 7
477
478 /*
479 * Pointer to the SCSI host sysfs attribute groups, NULL terminated.
480 */
481 const struct attribute_group **shost_groups;
482
483 /*
484 * Pointer to the SCSI device attribute groups for this host,
485 * NULL terminated.
486 */
487 const struct attribute_group **sdev_groups;
488
489 /*
490 * Vendor Identifier associated with the host
491 *
492 * Note: When specifying vendor_id, be sure to read the
493 * Vendor Type and ID formatting requirements specified in
494 * scsi_netlink.h
495 */
496 u64 vendor_id;
497
498 /* Delay for runtime autosuspend */
499 int rpm_autosuspend_delay;
500 };
501
502 /*
503 * Temporary #define for host lock push down. Can be removed when all
504 * drivers have been updated to take advantage of unlocked
505 * queuecommand.
506 *
507 */
508 #define DEF_SCSI_QCMD(func_name) \
509 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
510 { \
511 unsigned long irq_flags; \
512 int rc; \
513 spin_lock_irqsave(shost->host_lock, irq_flags); \
514 rc = func_name##_lck(cmd); \
515 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
516 return rc; \
517 }
518
519
520 /*
521 * shost state: If you alter this, you also need to alter scsi_sysfs.c
522 * (for the ascii descriptions) and the state model enforcer:
523 * scsi_host_set_state()
524 */
525 enum scsi_host_state {
526 SHOST_CREATED = 1,
527 SHOST_RUNNING,
528 SHOST_CANCEL,
529 SHOST_DEL,
530 SHOST_RECOVERY,
531 SHOST_CANCEL_RECOVERY,
532 SHOST_DEL_RECOVERY,
533 };
534
535 struct Scsi_Host {
536 /*
537 * __devices is protected by the host_lock, but you should
538 * usually use scsi_device_lookup / shost_for_each_device
539 * to access it and don't care about locking yourself.
540 * In the rare case of being in irq context you can use
541 * their __ prefixed variants with the lock held. NEVER
542 * access this list directly from a driver.
543 */
544 struct list_head __devices;
545 struct list_head __targets;
546
547 struct list_head starved_list;
548
549 spinlock_t default_lock;
550 spinlock_t *host_lock;
551
552 struct mutex scan_mutex;/* serialize scanning activity */
553
554 struct list_head eh_abort_list;
555 struct list_head eh_cmd_q;
556 struct task_struct * ehandler; /* Error recovery thread. */
557 struct completion * eh_action; /* Wait for specific actions on the
558 host. */
559 wait_queue_head_t host_wait;
560 const struct scsi_host_template *hostt;
561 struct scsi_transport_template *transportt;
562
563 struct kref tagset_refcnt;
564 struct completion tagset_freed;
565 /* Area to keep a shared tag map */
566 struct blk_mq_tag_set tag_set;
567
568 atomic_t host_blocked;
569
570 unsigned int host_failed; /* commands that failed.
571 protected by host_lock */
572 unsigned int host_eh_scheduled; /* EH scheduled without command */
573
574 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
575
576 /* next two fields are used to bound the time spent in error handling */
577 int eh_deadline;
578 unsigned long last_reset;
579
580
581 /*
582 * These three parameters can be used to allow for wide scsi,
583 * and for host adapters that support multiple busses
584 * The last two should be set to 1 more than the actual max id
585 * or lun (e.g. 8 for SCSI parallel systems).
586 */
587 unsigned int max_channel;
588 unsigned int max_id;
589 u64 max_lun;
590
591 /*
592 * This is a unique identifier that must be assigned so that we
593 * have some way of identifying each detected host adapter properly
594 * and uniquely. For hosts that do not support more than one card
595 * in the system at one time, this does not need to be set. It is
596 * initialized to 0 in scsi_register.
597 */
598 unsigned int unique_id;
599
600 /*
601 * The maximum length of SCSI commands that this host can accept.
602 * Probably 12 for most host adapters, but could be 16 for others.
603 * or 260 if the driver supports variable length cdbs.
604 * For drivers that don't set this field, a value of 12 is
605 * assumed.
606 */
607 unsigned short max_cmd_len;
608
609 int this_id;
610 int can_queue;
611 short cmd_per_lun;
612 short unsigned int sg_tablesize;
613 short unsigned int sg_prot_tablesize;
614 unsigned int max_sectors;
615 unsigned int opt_sectors;
616 unsigned int max_segment_size;
617 unsigned long dma_boundary;
618 unsigned long virt_boundary_mask;
619 /*
620 * In scsi-mq mode, the number of hardware queues supported by the LLD.
621 *
622 * Note: it is assumed that each hardware queue has a queue depth of
623 * can_queue. In other words, the total queue depth per host
624 * is nr_hw_queues * can_queue. However, for when host_tagset is set,
625 * the total queue depth is can_queue.
626 */
627 unsigned nr_hw_queues;
628 unsigned nr_maps;
629 unsigned active_mode:2;
630
631 /*
632 * Host has requested that no further requests come through for the
633 * time being.
634 */
635 unsigned host_self_blocked:1;
636
637 /*
638 * Host uses correct SCSI ordering not PC ordering. The bit is
639 * set for the minority of drivers whose authors actually read
640 * the spec ;).
641 */
642 unsigned reverse_ordering:1;
643
644 /* Task mgmt function in progress */
645 unsigned tmf_in_progress:1;
646
647 /* Asynchronous scan in progress */
648 unsigned async_scan:1;
649
650 /* Don't resume host in EH */
651 unsigned eh_noresume:1;
652
653 /* The controller does not support WRITE SAME */
654 unsigned no_write_same:1;
655
656 /* True if the host uses host-wide tagspace */
657 unsigned host_tagset:1;
658
659 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
660 unsigned queuecommand_may_block:1;
661
662 /* Host responded with short (<36 bytes) INQUIRY result */
663 unsigned short_inquiry:1;
664
665 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
666 unsigned no_scsi2_lun_in_cdb:1;
667
668 /*
669 * Optional work queue to be utilized by the transport
670 */
671 char work_q_name[20];
672 struct workqueue_struct *work_q;
673
674 /*
675 * Task management function work queue
676 */
677 struct workqueue_struct *tmf_work_q;
678
679 /*
680 * Value host_blocked counts down from
681 */
682 unsigned int max_host_blocked;
683
684 /* Protection Information */
685 unsigned int prot_capabilities;
686 unsigned char prot_guard_type;
687
688 /* legacy crap */
689 unsigned long base;
690 unsigned long io_port;
691 unsigned char n_io_port;
692 unsigned char dma_channel;
693 unsigned int irq;
694
695
696 enum scsi_host_state shost_state;
697
698 /* ldm bits */
699 struct device shost_gendev, shost_dev;
700
701 /*
702 * Points to the transport data (if any) which is allocated
703 * separately
704 */
705 void *shost_data;
706
707 /*
708 * Points to the physical bus device we'd use to do DMA
709 * Needed just in case we have virtual hosts.
710 */
711 struct device *dma_dev;
712
713 /*
714 * We should ensure that this is aligned, both for better performance
715 * and also because some compilers (m68k) don't automatically force
716 * alignment to a long boundary.
717 */
718 unsigned long hostdata[] /* Used for storage of host specific stuff */
719 __attribute__ ((aligned (sizeof(unsigned long))));
720 };
721
722 #define class_to_shost(d) \
723 container_of(d, struct Scsi_Host, shost_dev)
724
725 #define shost_printk(prefix, shost, fmt, a...) \
726 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
727
shost_priv(struct Scsi_Host * shost)728 static inline void *shost_priv(struct Scsi_Host *shost)
729 {
730 return (void *)shost->hostdata;
731 }
732
733 int scsi_is_host_device(const struct device *);
734
dev_to_shost(struct device * dev)735 static inline struct Scsi_Host *dev_to_shost(struct device *dev)
736 {
737 while (!scsi_is_host_device(dev)) {
738 if (!dev->parent)
739 return NULL;
740 dev = dev->parent;
741 }
742 return container_of(dev, struct Scsi_Host, shost_gendev);
743 }
744
scsi_host_in_recovery(struct Scsi_Host * shost)745 static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
746 {
747 return shost->shost_state == SHOST_RECOVERY ||
748 shost->shost_state == SHOST_CANCEL_RECOVERY ||
749 shost->shost_state == SHOST_DEL_RECOVERY ||
750 shost->tmf_in_progress;
751 }
752
753 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
754 extern void scsi_flush_work(struct Scsi_Host *);
755
756 extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int);
757 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
758 struct device *,
759 struct device *);
760 #if defined(CONFIG_SCSI_PROC_FS)
761 struct proc_dir_entry *
762 scsi_template_proc_dir(const struct scsi_host_template *sht);
763 #else
764 #define scsi_template_proc_dir(sht) NULL
765 #endif
766 extern void scsi_scan_host(struct Scsi_Host *);
767 extern int scsi_resume_device(struct scsi_device *sdev);
768 extern int scsi_rescan_device(struct scsi_device *sdev);
769 extern void scsi_remove_host(struct Scsi_Host *);
770 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
771 extern int scsi_host_busy(struct Scsi_Host *shost);
772 extern void scsi_host_put(struct Scsi_Host *t);
773 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum);
774 extern const char *scsi_host_state_name(enum scsi_host_state);
775 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,
776 enum scsi_host_status status);
777
scsi_add_host(struct Scsi_Host * host,struct device * dev)778 static inline int __must_check scsi_add_host(struct Scsi_Host *host,
779 struct device *dev)
780 {
781 return scsi_add_host_with_dma(host, dev, dev);
782 }
783
scsi_get_device(struct Scsi_Host * shost)784 static inline struct device *scsi_get_device(struct Scsi_Host *shost)
785 {
786 return shost->shost_gendev.parent;
787 }
788
789 /**
790 * scsi_host_scan_allowed - Is scanning of this host allowed
791 * @shost: Pointer to Scsi_Host.
792 **/
scsi_host_scan_allowed(struct Scsi_Host * shost)793 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
794 {
795 return shost->shost_state == SHOST_RUNNING ||
796 shost->shost_state == SHOST_RECOVERY;
797 }
798
799 extern void scsi_unblock_requests(struct Scsi_Host *);
800 extern void scsi_block_requests(struct Scsi_Host *);
801 extern int scsi_host_block(struct Scsi_Host *shost);
802 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
803
804 void scsi_host_busy_iter(struct Scsi_Host *,
805 bool (*fn)(struct scsi_cmnd *, void *), void *priv);
806
807 struct class_container;
808
809 /*
810 * DIF defines the exchange of protection information between
811 * initiator and SBC block device.
812 *
813 * DIX defines the exchange of protection information between OS and
814 * initiator.
815 */
816 enum scsi_host_prot_capabilities {
817 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
818 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
819 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
820
821 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
822 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
823 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
824 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
825 };
826
827 /*
828 * SCSI hosts which support the Data Integrity Extensions must
829 * indicate their capabilities by setting the prot_capabilities using
830 * this call.
831 */
scsi_host_set_prot(struct Scsi_Host * shost,unsigned int mask)832 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
833 {
834 shost->prot_capabilities = mask;
835 }
836
scsi_host_get_prot(struct Scsi_Host * shost)837 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
838 {
839 return shost->prot_capabilities;
840 }
841
scsi_host_prot_dma(struct Scsi_Host * shost)842 static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
843 {
844 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
845 }
846
scsi_host_dif_capable(struct Scsi_Host * shost,unsigned int target_type)847 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
848 {
849 static unsigned char cap[] = { 0,
850 SHOST_DIF_TYPE1_PROTECTION,
851 SHOST_DIF_TYPE2_PROTECTION,
852 SHOST_DIF_TYPE3_PROTECTION };
853
854 if (target_type >= ARRAY_SIZE(cap))
855 return 0;
856
857 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
858 }
859
scsi_host_dix_capable(struct Scsi_Host * shost,unsigned int target_type)860 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
861 {
862 #if defined(CONFIG_BLK_DEV_INTEGRITY)
863 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
864 SHOST_DIX_TYPE1_PROTECTION,
865 SHOST_DIX_TYPE2_PROTECTION,
866 SHOST_DIX_TYPE3_PROTECTION };
867
868 if (target_type >= ARRAY_SIZE(cap))
869 return 0;
870
871 return shost->prot_capabilities & cap[target_type];
872 #endif
873 return 0;
874 }
875
876 /*
877 * All DIX-capable initiators must support the T10-mandated CRC
878 * checksum. Controllers can optionally implement the IP checksum
879 * scheme which has much lower impact on system performance. Note
880 * that the main rationale for the checksum is to match integrity
881 * metadata with data. Detecting bit errors are a job for ECC memory
882 * and buses.
883 */
884
885 enum scsi_host_guard_type {
886 SHOST_DIX_GUARD_CRC = 1 << 0,
887 SHOST_DIX_GUARD_IP = 1 << 1,
888 };
889
scsi_host_set_guard(struct Scsi_Host * shost,unsigned char type)890 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
891 {
892 shost->prot_guard_type = type;
893 }
894
scsi_host_get_guard(struct Scsi_Host * shost)895 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
896 {
897 return shost->prot_guard_type;
898 }
899
900 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
901
902 #endif /* _SCSI_SCSI_HOST_H */
903