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