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_target;
20struct Scsi_Host;
21struct 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 */
36enum scsi_timeout_action {
37 SCSI_EH_DONE,
38 SCSI_EH_RESET_TIMER,
39 SCSI_EH_NOT_HANDLED,
40};
41
42struct 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 sdev_destroy(). If we find something
172 * here then you will get a call to sdev_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 sdev_destroy(). This is
176 * assuming you implement sdev_configure and sdev_destroy.
177 * However, if you allocate memory and hang it off the device struct,
178 * then you must implement the sdev_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 (* sdev_init)(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 sdev_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 (* sdev_configure)(struct scsi_device *, struct queue_limits *lim);
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 sdev_init or sdev_configure calls.
223 *
224 * Status: OPTIONAL
225 */
226 void (* sdev_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 * Note: This callback is called with the host lock held and hence
249 * must not sleep.
250 *
251 * Status: OPTIONAL
252 */
253 void (* target_destroy)(struct scsi_target *);
254
255 /*
256 * If a host has the ability to discover targets on its own instead
257 * of scanning the entire bus, it can fill in this function and
258 * call scsi_scan_host(). This function will be called periodically
259 * until it returns 1 with the scsi_host and the elapsed time of
260 * the scan in jiffies.
261 *
262 * Status: OPTIONAL
263 */
264 int (* scan_finished)(struct Scsi_Host *, unsigned long);
265
266 /*
267 * If the host wants to be called before the scan starts, but
268 * after the midlayer has set up ready for the scan, it can fill
269 * in this function.
270 *
271 * Status: OPTIONAL
272 */
273 void (* scan_start)(struct Scsi_Host *);
274
275 /*
276 * Fill in this function to allow the queue depth of this host
277 * to be changeable (on a per device basis). Returns either
278 * the current queue depth setting (may be different from what
279 * was passed in) or an error. An error should only be
280 * returned if the requested depth is legal but the driver was
281 * unable to set it. If the requested depth is illegal, the
282 * driver should set and return the closest legal queue depth.
283 *
284 * Status: OPTIONAL
285 */
286 int (* change_queue_depth)(struct scsi_device *, int);
287
288 /*
289 * This functions lets the driver expose the queue mapping
290 * to the block layer.
291 *
292 * Status: OPTIONAL
293 */
294 void (* map_queues)(struct Scsi_Host *shost);
295
296 /*
297 * SCSI interface of blk_poll - poll for IO completions.
298 * Only applicable if SCSI LLD exposes multiple h/w queues.
299 *
300 * Return value: Number of completed entries found.
301 *
302 * Status: OPTIONAL
303 */
304 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num);
305
306 /*
307 * Check if scatterlists need to be padded for DMA draining.
308 *
309 * Status: OPTIONAL
310 */
311 bool (* dma_need_drain)(struct request *rq);
312
313 /*
314 * This function determines the BIOS parameters for a given
315 * harddisk. These tend to be numbers that are made up by
316 * the host adapter. Parameters:
317 * size, device, list (heads, sectors, cylinders)
318 *
319 * Status: OPTIONAL
320 */
321 int (* bios_param)(struct scsi_device *, struct gendisk *,
322 sector_t, int []);
323
324 /*
325 * This function is called when one or more partitions on the
326 * device reach beyond the end of the device.
327 *
328 * Status: OPTIONAL
329 */
330 void (*unlock_native_capacity)(struct scsi_device *);
331
332 /*
333 * Can be used to export driver statistics and other infos to the
334 * world outside the kernel ie. userspace and it also provides an
335 * interface to feed the driver with information.
336 *
337 * Status: OBSOLETE
338 */
339 int (*show_info)(struct seq_file *, struct Scsi_Host *);
340 int (*write_info)(struct Scsi_Host *, char *, int);
341
342 /*
343 * This is an optional routine that allows the transport to become
344 * involved when a scsi io timer fires. The return value tells the
345 * timer routine how to finish the io timeout handling.
346 *
347 * Status: OPTIONAL
348 */
349 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *);
350 /*
351 * Optional routine that allows the transport to decide if a cmd
352 * is retryable. Return true if the transport is in a state the
353 * cmd should be retried on.
354 */
355 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd);
356
357 /* This is an optional routine that allows transport to initiate
358 * LLD adapter or firmware reset using sysfs attribute.
359 *
360 * Return values: 0 on success, -ve value on failure.
361 *
362 * Status: OPTIONAL
363 */
364
365 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
366#define SCSI_ADAPTER_RESET 1
367#define SCSI_FIRMWARE_RESET 2
368
369
370 /*
371 * Name of proc directory
372 */
373 const char *proc_name;
374
375 /*
376 * This determines if we will use a non-interrupt driven
377 * or an interrupt driven scheme. It is set to the maximum number
378 * of simultaneous commands a single hw queue in HBA will accept.
379 */
380 int can_queue;
381
382 /*
383 * In many instances, especially where disconnect / reconnect are
384 * supported, our host also has an ID on the SCSI bus. If this is
385 * the case, then it must be reserved. Please set this_id to -1 if
386 * your setup is in single initiator mode, and the host lacks an
387 * ID.
388 */
389 int this_id;
390
391 /*
392 * This determines the degree to which the host adapter is capable
393 * of scatter-gather.
394 */
395 unsigned short sg_tablesize;
396 unsigned short sg_prot_tablesize;
397
398 /*
399 * Set this if the host adapter has limitations beside segment count.
400 */
401 unsigned int max_sectors;
402
403 /*
404 * Maximum size in bytes of a single segment.
405 */
406 unsigned int max_segment_size;
407
408 unsigned int dma_alignment;
409
410 /*
411 * DMA scatter gather segment boundary limit. A segment crossing this
412 * boundary will be split in two.
413 */
414 unsigned long dma_boundary;
415
416 unsigned long virt_boundary_mask;
417
418 /*
419 * This specifies "machine infinity" for host templates which don't
420 * limit the transfer size. Note this limit represents an absolute
421 * maximum, and may be over the transfer limits allowed for
422 * individual devices (e.g. 256 for SCSI-1).
423 */
424#define SCSI_DEFAULT_MAX_SECTORS 1024
425
426 /*
427 * True if this host adapter can make good use of linked commands.
428 * This will allow more than one command to be queued to a given
429 * unit on a given host. Set this to the maximum number of command
430 * blocks to be provided for each device. Set this to 1 for one
431 * command block per lun, 2 for two, etc. Do not set this to 0.
432 * You should make sure that the host adapter will do the right thing
433 * before you try setting this above 1.
434 */
435 short cmd_per_lun;
436
437 /*
438 * Allocate tags starting from last allocated tag.
439 */
440 bool tag_alloc_policy_rr : 1;
441
442 /*
443 * Track QUEUE_FULL events and reduce queue depth on demand.
444 */
445 unsigned track_queue_depth:1;
446
447 /*
448 * This specifies the mode that a LLD supports.
449 */
450 unsigned supported_mode:2;
451
452 /*
453 * True for emulated SCSI host adapters (e.g. ATAPI).
454 */
455 unsigned emulated:1;
456
457 /*
458 * True if the low-level driver performs its own reset-settle delays.
459 */
460 unsigned skip_settle_delay:1;
461
462 /* True if the controller does not support WRITE SAME */
463 unsigned no_write_same:1;
464
465 /* True if the host uses host-wide tagspace */
466 unsigned host_tagset:1;
467
468 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
469 unsigned queuecommand_may_block:1;
470
471 /*
472 * Countdown for host blocking with no commands outstanding.
473 */
474 unsigned int max_host_blocked;
475
476 /*
477 * Default value for the blocking. If the queue is empty,
478 * host_blocked counts down in the request_fn until it restarts
479 * host operations as zero is reached.
480 *
481 * FIXME: This should probably be a value in the template
482 */
483#define SCSI_DEFAULT_HOST_BLOCKED 7
484
485 /*
486 * Pointer to the SCSI host sysfs attribute groups, NULL terminated.
487 */
488 const struct attribute_group **shost_groups;
489
490 /*
491 * Pointer to the SCSI device attribute groups for this host,
492 * NULL terminated.
493 */
494 const struct attribute_group **sdev_groups;
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 rc = func_name##_lck(cmd); \
519 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
520 return rc; \
521 }
522
523
524/*
525 * shost state: If you alter this, you also need to alter scsi_sysfs.c
526 * (for the ascii descriptions) and the state model enforcer:
527 * scsi_host_set_state()
528 */
529enum scsi_host_state {
530 SHOST_CREATED = 1,
531 SHOST_RUNNING,
532 SHOST_CANCEL,
533 SHOST_DEL,
534 SHOST_RECOVERY,
535 SHOST_CANCEL_RECOVERY,
536 SHOST_DEL_RECOVERY,
537};
538
539struct Scsi_Host {
540 /*
541 * __devices is protected by the host_lock, but you should
542 * usually use scsi_device_lookup / shost_for_each_device
543 * to access it and don't care about locking yourself.
544 * In the rare case of being in irq context you can use
545 * their __ prefixed variants with the lock held. NEVER
546 * access this list directly from a driver.
547 */
548 struct list_head __devices;
549 struct list_head __targets;
550
551 struct list_head starved_list;
552
553 spinlock_t default_lock;
554 spinlock_t *host_lock;
555
556 struct mutex scan_mutex;/* serialize scanning activity */
557
558 struct list_head eh_abort_list;
559 struct list_head eh_cmd_q;
560 struct task_struct * ehandler; /* Error recovery thread. */
561 struct completion * eh_action; /* Wait for specific actions on the
562 host. */
563 wait_queue_head_t host_wait;
564 const struct scsi_host_template *hostt;
565 struct scsi_transport_template *transportt;
566
567 struct kref tagset_refcnt;
568 struct completion tagset_freed;
569 /* Area to keep a shared tag map */
570 struct blk_mq_tag_set tag_set;
571
572 atomic_t host_blocked;
573
574 unsigned int host_failed; /* commands that failed.
575 protected by host_lock */
576 unsigned int host_eh_scheduled; /* EH scheduled without command */
577
578 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
579
580 /* next two fields are used to bound the time spent in error handling */
581 int eh_deadline;
582 unsigned long last_reset;
583
584
585 /*
586 * These three parameters can be used to allow for wide scsi,
587 * and for host adapters that support multiple busses
588 * The last two should be set to 1 more than the actual max id
589 * or lun (e.g. 8 for SCSI parallel systems).
590 */
591 unsigned int max_channel;
592 unsigned int max_id;
593 u64 max_lun;
594
595 /*
596 * This is a unique identifier that must be assigned so that we
597 * have some way of identifying each detected host adapter properly
598 * and uniquely. For hosts that do not support more than one card
599 * in the system at one time, this does not need to be set. It is
600 * initialized to 0 in scsi_host_alloc.
601 */
602 unsigned int unique_id;
603
604 /*
605 * The maximum length of SCSI commands that this host can accept.
606 * Probably 12 for most host adapters, but could be 16 for others.
607 * or 260 if the driver supports variable length cdbs.
608 * For drivers that don't set this field, a value of 12 is
609 * assumed.
610 */
611 unsigned short max_cmd_len;
612
613 int this_id;
614 int can_queue;
615 short cmd_per_lun;
616 short unsigned int sg_tablesize;
617 short unsigned int sg_prot_tablesize;
618 unsigned int max_sectors;
619 unsigned int opt_sectors;
620 unsigned int max_segment_size;
621 unsigned int dma_alignment;
622 unsigned long dma_boundary;
623 unsigned long virt_boundary_mask;
624 /*
625 * In scsi-mq mode, the number of hardware queues supported by the LLD.
626 *
627 * Note: it is assumed that each hardware queue has a queue depth of
628 * can_queue. In other words, the total queue depth per host
629 * is nr_hw_queues * can_queue. However, for when host_tagset is set,
630 * the total queue depth is can_queue.
631 */
632 unsigned nr_hw_queues;
633 unsigned nr_maps;
634 unsigned active_mode:2;
635
636 /*
637 * Host has requested that no further requests come through for the
638 * time being.
639 */
640 unsigned host_self_blocked:1;
641
642 /*
643 * Host uses correct SCSI ordering not PC ordering. The bit is
644 * set for the minority of drivers whose authors actually read
645 * the spec ;).
646 */
647 unsigned reverse_ordering:1;
648
649 /* Task mgmt function in progress */
650 unsigned tmf_in_progress:1;
651
652 /* Asynchronous scan in progress */
653 unsigned async_scan:1;
654
655 /* Don't resume host in EH */
656 unsigned eh_noresume:1;
657
658 /* The controller does not support WRITE SAME */
659 unsigned no_write_same:1;
660
661 /* True if the host uses host-wide tagspace */
662 unsigned host_tagset:1;
663
664 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
665 unsigned queuecommand_may_block:1;
666
667 /* Host responded with short (<36 bytes) INQUIRY result */
668 unsigned short_inquiry:1;
669
670 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
671 unsigned no_scsi2_lun_in_cdb:1;
672
673 /*
674 * Optional work queue to be utilized by the transport
675 */
676 struct workqueue_struct *work_q;
677
678 /*
679 * Task management function work queue
680 */
681 struct workqueue_struct *tmf_work_q;
682
683 /*
684 * Value host_blocked counts down from
685 */
686 unsigned int max_host_blocked;
687
688 /* Protection Information */
689 unsigned int prot_capabilities;
690 unsigned char prot_guard_type;
691
692 /* legacy crap */
693 unsigned long base;
694 unsigned long io_port;
695 unsigned char n_io_port;
696 unsigned char dma_channel;
697 unsigned int irq;
698
699
700 enum scsi_host_state shost_state;
701
702 /* ldm bits */
703 struct device shost_gendev, shost_dev;
704
705 /*
706 * Points to the transport data (if any) which is allocated
707 * separately
708 */
709 void *shost_data;
710
711 /*
712 * Points to the physical bus device we'd use to do DMA
713 * Needed just in case we have virtual hosts.
714 */
715 struct device *dma_dev;
716
717 /* Delay for runtime autosuspend */
718 int rpm_autosuspend_delay;
719
720 /*
721 * We should ensure that this is aligned, both for better performance
722 * and also because some compilers (m68k) don't automatically force
723 * alignment to a long boundary.
724 */
725 unsigned long hostdata[] /* Used for storage of host specific stuff */
726 __attribute__ ((aligned (sizeof(unsigned long))));
727};
728
729#define class_to_shost(d) \
730 container_of(d, struct Scsi_Host, shost_dev)
731
732#define shost_printk(prefix, shost, fmt, a...) \
733 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
734
735static inline void *shost_priv(struct Scsi_Host *shost)
736{
737 return (void *)shost->hostdata;
738}
739
740int scsi_is_host_device(const struct device *);
741
742static inline struct Scsi_Host *dev_to_shost(struct device *dev)
743{
744 while (!scsi_is_host_device(dev)) {
745 if (!dev->parent)
746 return NULL;
747 dev = dev->parent;
748 }
749 return container_of(dev, struct Scsi_Host, shost_gendev);
750}
751
752static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
753{
754 return shost->shost_state == SHOST_RECOVERY ||
755 shost->shost_state == SHOST_CANCEL_RECOVERY ||
756 shost->shost_state == SHOST_DEL_RECOVERY ||
757 shost->tmf_in_progress;
758}
759
760extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
761extern void scsi_flush_work(struct Scsi_Host *);
762
763extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int);
764extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
765 struct device *,
766 struct device *);
767#if defined(CONFIG_SCSI_PROC_FS)
768struct proc_dir_entry *
769scsi_template_proc_dir(const struct scsi_host_template *sht);
770#else
771#define scsi_template_proc_dir(sht) NULL
772#endif
773extern void scsi_scan_host(struct Scsi_Host *);
774extern int scsi_resume_device(struct scsi_device *sdev);
775extern int scsi_rescan_device(struct scsi_device *sdev);
776extern void scsi_remove_host(struct Scsi_Host *);
777extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
778extern int scsi_host_busy(struct Scsi_Host *shost);
779extern void scsi_host_put(struct Scsi_Host *t);
780extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum);
781extern const char *scsi_host_state_name(enum scsi_host_state);
782extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,
783 enum scsi_host_status status);
784
785static inline int __must_check scsi_add_host(struct Scsi_Host *host,
786 struct device *dev)
787{
788 return scsi_add_host_with_dma(host, dev, dev);
789}
790
791static inline struct device *scsi_get_device(struct Scsi_Host *shost)
792{
793 return shost->shost_gendev.parent;
794}
795
796/**
797 * scsi_host_scan_allowed - Is scanning of this host allowed
798 * @shost: Pointer to Scsi_Host.
799 **/
800static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
801{
802 return shost->shost_state == SHOST_RUNNING ||
803 shost->shost_state == SHOST_RECOVERY;
804}
805
806extern void scsi_unblock_requests(struct Scsi_Host *);
807extern void scsi_block_requests(struct Scsi_Host *);
808extern int scsi_host_block(struct Scsi_Host *shost);
809extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
810
811void scsi_host_busy_iter(struct Scsi_Host *,
812 bool (*fn)(struct scsi_cmnd *, void *), void *priv);
813
814struct class_container;
815
816/*
817 * DIF defines the exchange of protection information between
818 * initiator and SBC block device.
819 *
820 * DIX defines the exchange of protection information between OS and
821 * initiator.
822 */
823enum scsi_host_prot_capabilities {
824 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
825 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
826 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
827
828 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
829 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
830 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
831 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
832};
833
834/*
835 * SCSI hosts which support the Data Integrity Extensions must
836 * indicate their capabilities by setting the prot_capabilities using
837 * this call.
838 */
839static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
840{
841 shost->prot_capabilities = mask;
842}
843
844static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
845{
846 return shost->prot_capabilities;
847}
848
849static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
850{
851 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
852}
853
854static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
855{
856 static unsigned char cap[] = { 0,
857 SHOST_DIF_TYPE1_PROTECTION,
858 SHOST_DIF_TYPE2_PROTECTION,
859 SHOST_DIF_TYPE3_PROTECTION };
860
861 if (target_type >= ARRAY_SIZE(cap))
862 return 0;
863
864 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
865}
866
867static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
868{
869#if defined(CONFIG_BLK_DEV_INTEGRITY)
870 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
871 SHOST_DIX_TYPE1_PROTECTION,
872 SHOST_DIX_TYPE2_PROTECTION,
873 SHOST_DIX_TYPE3_PROTECTION };
874
875 if (target_type >= ARRAY_SIZE(cap))
876 return 0;
877
878 return shost->prot_capabilities & cap[target_type];
879#endif
880 return 0;
881}
882
883/*
884 * All DIX-capable initiators must support the T10-mandated CRC
885 * checksum. Controllers can optionally implement the IP checksum
886 * scheme which has much lower impact on system performance. Note
887 * that the main rationale for the checksum is to match integrity
888 * metadata with data. Detecting bit errors are a job for ECC memory
889 * and buses.
890 */
891
892enum scsi_host_guard_type {
893 SHOST_DIX_GUARD_CRC = 1 << 0,
894 SHOST_DIX_GUARD_IP = 1 << 1,
895};
896
897static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
898{
899 shost->prot_guard_type = type;
900}
901
902static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
903{
904 return shost->prot_guard_type;
905}
906
907extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
908
909#endif /* _SCSI_SCSI_HOST_H */
910