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 #define SG_ALL SG_CHUNK_SIZE
28
29 #define MODE_UNKNOWN 0x00
30 #define MODE_INITIATOR 0x01
31 #define MODE_TARGET 0x02
32
33 /**
34 * enum scsi_timeout_action - How to handle a command that timed out.
35 * @SCSI_EH_DONE: The command has already been completed.
36 * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion.
37 * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command.
38 */
39 enum scsi_timeout_action {
40 SCSI_EH_DONE,
41 SCSI_EH_RESET_TIMER,
42 SCSI_EH_NOT_HANDLED,
43 };
44
45 struct 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 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
79 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
80
81 /*
82 * The queuecommand function is used to queue up a scsi
83 * command block to the LLDD. When the driver finished
84 * processing the command the done callback is invoked.
85 *
86 * If queuecommand returns 0, then the driver has accepted the
87 * command. It must also push it to the HBA if the scsi_cmnd
88 * flag SCMD_LAST is set, or if the driver does not implement
89 * commit_rqs. The done() function must be called on the command
90 * when the driver has finished with it. (you may call done on the
91 * command before queuecommand returns, but in this case you
92 * *must* return 0 from queuecommand).
93 *
94 * Queuecommand may also reject the command, in which case it may
95 * not touch the command and must not call done() for it.
96 *
97 * There are two possible rejection returns:
98 *
99 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
100 * allow commands to other devices serviced by this host.
101 *
102 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
103 * host temporarily.
104 *
105 * For compatibility, any other non-zero return is treated the
106 * same as SCSI_MLQUEUE_HOST_BUSY.
107 *
108 * NOTE: "temporarily" means either until the next command for#
109 * this device/host completes, or a period of time determined by
110 * I/O pressure in the system if there are no other outstanding
111 * commands.
112 *
113 * STATUS: REQUIRED
114 */
115 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
116
117 /*
118 * The commit_rqs function is used to trigger a hardware
119 * doorbell after some requests have been queued with
120 * queuecommand, when an error is encountered before sending
121 * the request with SCMD_LAST set.
122 *
123 * STATUS: OPTIONAL
124 */
125 void (*commit_rqs)(struct Scsi_Host *, u16);
126
127 /*
128 * This is an error handling strategy routine. You don't need to
129 * define one of these if you don't want to - there is a default
130 * routine that is present that should work in most cases. For those
131 * driver authors that have the inclination and ability to write their
132 * own strategy routine, this is where it is specified. Note - the
133 * strategy routine is *ALWAYS* run in the context of the kernel eh
134 * thread. Thus you are guaranteed to *NOT* be in an interrupt
135 * handler when you execute this, and you are also guaranteed to
136 * *NOT* have any other commands being queued while you are in the
137 * strategy routine. When you return from this function, operations
138 * return to normal.
139 *
140 * See scsi_error.c scsi_unjam_host for additional comments about
141 * what this function should and should not be attempting to do.
142 *
143 * Status: REQUIRED (at least one of them)
144 */
145 int (* eh_abort_handler)(struct scsi_cmnd *);
146 int (* eh_device_reset_handler)(struct scsi_cmnd *);
147 int (* eh_target_reset_handler)(struct scsi_cmnd *);
148 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
149 int (* eh_host_reset_handler)(struct scsi_cmnd *);
150
151 /*
152 * Before the mid layer attempts to scan for a new device where none
153 * currently exists, it will call this entry in your driver. Should
154 * your driver need to allocate any structs or perform any other init
155 * items in order to send commands to a currently unused target/lun
156 * combo, then this is where you can perform those allocations. This
157 * is specifically so that drivers won't have to perform any kind of
158 * "is this a new device" checks in their queuecommand routine,
159 * thereby making the hot path a bit quicker.
160 *
161 * Return values: 0 on success, non-0 on failure
162 *
163 * Deallocation: If we didn't find any devices at this ID, you will
164 * get an immediate call to slave_destroy(). If we find something
165 * here then you will get a call to slave_configure(), then the
166 * device will be used for however long it is kept around, then when
167 * the device is removed from the system (or * possibly at reboot
168 * time), you will then get a call to slave_destroy(). This is
169 * assuming you implement slave_configure and slave_destroy.
170 * However, if you allocate memory and hang it off the device struct,
171 * then you must implement the slave_destroy() routine at a minimum
172 * in order to avoid leaking memory
173 * each time a device is tore down.
174 *
175 * Status: OPTIONAL
176 */
177 int (* slave_alloc)(struct scsi_device *);
178
179 /*
180 * Once the device has responded to an INQUIRY and we know the
181 * device is online, we call into the low level driver with the
182 * struct scsi_device *. If the low level device driver implements
183 * this function, it *must* perform the task of setting the queue
184 * depth on the device. All other tasks are optional and depend
185 * on what the driver supports and various implementation details.
186 *
187 * Things currently recommended to be handled at this time include:
188 *
189 * 1. Setting the device queue depth. Proper setting of this is
190 * described in the comments for scsi_change_queue_depth.
191 * 2. Determining if the device supports the various synchronous
192 * negotiation protocols. The device struct will already have
193 * responded to INQUIRY and the results of the standard items
194 * will have been shoved into the various device flag bits, eg.
195 * device->sdtr will be true if the device supports SDTR messages.
196 * 3. Allocating command structs that the device will need.
197 * 4. Setting the default timeout on this device (if needed).
198 * 5. Anything else the low level driver might want to do on a device
199 * specific setup basis...
200 * 6. Return 0 on success, non-0 on error. The device will be marked
201 * as offline on error so that no access will occur. If you return
202 * non-0, your slave_destroy routine will never get called for this
203 * device, so don't leave any loose memory hanging around, clean
204 * up after yourself before returning non-0
205 *
206 * Status: OPTIONAL
207 */
208 int (* slave_configure)(struct scsi_device *);
209
210 /*
211 * Immediately prior to deallocating the device and after all activity
212 * has ceased the mid layer calls this point so that the low level
213 * driver may completely detach itself from the scsi device and vice
214 * versa. The low level driver is responsible for freeing any memory
215 * it allocated in the slave_alloc or slave_configure calls.
216 *
217 * Status: OPTIONAL
218 */
219 void (* slave_destroy)(struct scsi_device *);
220
221 /*
222 * Before the mid layer attempts to scan for a new device attached
223 * to a target where no target currently exists, it will call this
224 * entry in your driver. Should your driver need to allocate any
225 * structs or perform any other init items in order to send commands
226 * to a currently unused target, then this is where you can perform
227 * those allocations.
228 *
229 * Return values: 0 on success, non-0 on failure
230 *
231 * Status: OPTIONAL
232 */
233 int (* target_alloc)(struct scsi_target *);
234
235 /*
236 * Immediately prior to deallocating the target structure, and
237 * after all activity to attached scsi devices has ceased, the
238 * midlayer calls this point so that the driver may deallocate
239 * and terminate any references to the target.
240 *
241 * Status: OPTIONAL
242 */
243 void (* target_destroy)(struct scsi_target *);
244
245 /*
246 * If a host has the ability to discover targets on its own instead
247 * of scanning the entire bus, it can fill in this function and
248 * call scsi_scan_host(). This function will be called periodically
249 * until it returns 1 with the scsi_host and the elapsed time of
250 * the scan in jiffies.
251 *
252 * Status: OPTIONAL
253 */
254 int (* scan_finished)(struct Scsi_Host *, unsigned long);
255
256 /*
257 * If the host wants to be called before the scan starts, but
258 * after the midlayer has set up ready for the scan, it can fill
259 * in this function.
260 *
261 * Status: OPTIONAL
262 */
263 void (* scan_start)(struct Scsi_Host *);
264
265 /*
266 * Fill in this function to allow the queue depth of this host
267 * to be changeable (on a per device basis). Returns either
268 * the current queue depth setting (may be different from what
269 * was passed in) or an error. An error should only be
270 * returned if the requested depth is legal but the driver was
271 * unable to set it. If the requested depth is illegal, the
272 * driver should set and return the closest legal queue depth.
273 *
274 * Status: OPTIONAL
275 */
276 int (* change_queue_depth)(struct scsi_device *, int);
277
278 /*
279 * This functions lets the driver expose the queue mapping
280 * to the block layer.
281 *
282 * Status: OPTIONAL
283 */
284 int (* map_queues)(struct Scsi_Host *shost);
285
286 /*
287 * SCSI interface of blk_poll - poll for IO completions.
288 * Only applicable if SCSI LLD exposes multiple h/w queues.
289 *
290 * Return value: Number of completed entries found.
291 *
292 * Status: OPTIONAL
293 */
294 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num);
295
296 /*
297 * Check if scatterlists need to be padded for DMA draining.
298 *
299 * Status: OPTIONAL
300 */
301 bool (* dma_need_drain)(struct request *rq);
302
303 /*
304 * This function determines the BIOS parameters for a given
305 * harddisk. These tend to be numbers that are made up by
306 * the host adapter. Parameters:
307 * size, device, list (heads, sectors, cylinders)
308 *
309 * Status: OPTIONAL
310 */
311 int (* bios_param)(struct scsi_device *, struct block_device *,
312 sector_t, int []);
313
314 /*
315 * This function is called when one or more partitions on the
316 * device reach beyond the end of the device.
317 *
318 * Status: OPTIONAL
319 */
320 void (*unlock_native_capacity)(struct scsi_device *);
321
322 /*
323 * Can be used to export driver statistics and other infos to the
324 * world outside the kernel ie. userspace and it also provides an
325 * interface to feed the driver with information.
326 *
327 * Status: OBSOLETE
328 */
329 int (*show_info)(struct seq_file *, struct Scsi_Host *);
330 int (*write_info)(struct Scsi_Host *, char *, int);
331
332 /*
333 * This is an optional routine that allows the transport to become
334 * involved when a scsi io timer fires. The return value tells the
335 * timer routine how to finish the io timeout handling.
336 *
337 * Status: OPTIONAL
338 */
339 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
340
341 /* This is an optional routine that allows transport to initiate
342 * LLD adapter or firmware reset using sysfs attribute.
343 *
344 * Return values: 0 on success, -ve value on failure.
345 *
346 * Status: OPTIONAL
347 */
348
349 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
350 #define SCSI_ADAPTER_RESET 1
351 #define SCSI_FIRMWARE_RESET 2
352
353
354 /*
355 * Name of proc directory
356 */
357 const char *proc_name;
358
359 /*
360 * Used to store the procfs directory if a driver implements the
361 * show_info method.
362 */
363 struct proc_dir_entry *proc_dir;
364
365 /*
366 * This determines if we will use a non-interrupt driven
367 * or an interrupt driven scheme. It is set to the maximum number
368 * of simultaneous commands a single hw queue in HBA will accept. Does
369 * not include @reserved_tags.
370 */
371 int can_queue;
372
373 /*
374 * Number of tags to reserve. A reserved tag can be allocated by passing
375 * the BLK_MQ_REQ_RESERVED flag to blk_mq_alloc_request().
376 */
377 unsigned reserved_tags;
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 /*
433 * present contains counter indicating how many boards of this
434 * type were found when we did the scan.
435 */
436 unsigned char present;
437
438 /* If use block layer to manage tags, this is tag allocation policy */
439 int tag_alloc_policy;
440
441 /*
442 * Track QUEUE_FULL events and reduce queue depth on demand.
443 */
444 unsigned track_queue_depth:1;
445
446 /*
447 * This specifies the mode that a LLD supports.
448 */
449 unsigned supported_mode:2;
450
451 /*
452 * True if this host adapter uses unchecked DMA onto an ISA bus.
453 */
454 unsigned unchecked_isa_dma:1;
455
456 /*
457 * True for emulated SCSI host adapters (e.g. ATAPI).
458 */
459 unsigned emulated:1;
460
461 /*
462 * True if the low-level driver performs its own reset-settle delays.
463 */
464 unsigned skip_settle_delay:1;
465
466 /* True if the controller does not support WRITE SAME */
467 unsigned no_write_same:1;
468
469 /* True if the host uses host-wide tagspace */
470 unsigned host_tagset:1;
471
472 /*
473 * Countdown for host blocking with no commands outstanding.
474 */
475 unsigned int max_host_blocked;
476
477 /*
478 * Default value for the blocking. If the queue is empty,
479 * host_blocked counts down in the request_fn until it restarts
480 * host operations as zero is reached.
481 *
482 * FIXME: This should probably be a value in the template
483 */
484 #define SCSI_DEFAULT_HOST_BLOCKED 7
485
486 /*
487 * Pointer to the sysfs class properties for this host, NULL terminated.
488 */
489 struct device_attribute **shost_attrs;
490
491 /*
492 * Pointer to the SCSI device properties for this host, NULL terminated.
493 */
494 struct device_attribute **sdev_attrs;
495
496 /*
497 * Pointer to the SCSI device attribute groups for this host,
498 * NULL terminated.
499 */
500 const struct attribute_group **sdev_groups;
501
502 /*
503 * Vendor Identifier associated with the host
504 *
505 * Note: When specifying vendor_id, be sure to read the
506 * Vendor Type and ID formatting requirements specified in
507 * scsi_netlink.h
508 */
509 u64 vendor_id;
510
511 /*
512 * Additional per-command data allocated for the driver.
513 */
514 unsigned int cmd_size;
515 struct scsi_host_cmd_pool *cmd_pool;
516
517 /* Delay for runtime autosuspend */
518 int rpm_autosuspend_delay;
519
520 ANDROID_KABI_USE(1, enum scsi_timeout_action (*eh_timed_out2)(struct scsi_cmnd *));
521 ANDROID_KABI_RESERVE(2);
522 ANDROID_KABI_RESERVE(3);
523 ANDROID_KABI_RESERVE(4);
524 };
525
526 /*
527 * Temporary #define for host lock push down. Can be removed when all
528 * drivers have been updated to take advantage of unlocked
529 * queuecommand.
530 *
531 */
532 #define DEF_SCSI_QCMD(func_name) \
533 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
534 { \
535 unsigned long irq_flags; \
536 int rc; \
537 spin_lock_irqsave(shost->host_lock, irq_flags); \
538 rc = func_name##_lck (cmd, cmd->scsi_done); \
539 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
540 return rc; \
541 }
542
543
544 /*
545 * shost state: If you alter this, you also need to alter scsi_sysfs.c
546 * (for the ascii descriptions) and the state model enforcer:
547 * scsi_host_set_state()
548 */
549 enum scsi_host_state {
550 SHOST_CREATED = 1,
551 SHOST_RUNNING,
552 SHOST_CANCEL,
553 SHOST_DEL,
554 SHOST_RECOVERY,
555 SHOST_CANCEL_RECOVERY,
556 SHOST_DEL_RECOVERY,
557 };
558
559 struct Scsi_Host {
560 /*
561 * __devices is protected by the host_lock, but you should
562 * usually use scsi_device_lookup / shost_for_each_device
563 * to access it and don't care about locking yourself.
564 * In the rare case of being in irq context you can use
565 * their __ prefixed variants with the lock held. NEVER
566 * access this list directly from a driver.
567 */
568 struct list_head __devices;
569 struct list_head __targets;
570
571 struct list_head starved_list;
572
573 spinlock_t default_lock;
574 spinlock_t *host_lock;
575
576 struct mutex scan_mutex;/* serialize scanning activity */
577
578 struct list_head eh_cmd_q;
579 struct task_struct * ehandler; /* Error recovery thread. */
580 struct completion * eh_action; /* Wait for specific actions on the
581 host. */
582 wait_queue_head_t host_wait;
583 struct scsi_host_template *hostt;
584 struct scsi_transport_template *transportt;
585
586 /* Area to keep a shared tag map */
587 struct blk_mq_tag_set tag_set;
588
589 atomic_t host_blocked;
590
591 unsigned int host_failed; /* commands that failed.
592 protected by host_lock */
593 unsigned int host_eh_scheduled; /* EH scheduled without command */
594
595 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
596
597 /* next two fields are used to bound the time spent in error handling */
598 int eh_deadline;
599 unsigned long last_reset;
600
601
602 /*
603 * These three parameters can be used to allow for wide scsi,
604 * and for host adapters that support multiple busses
605 * The last two should be set to 1 more than the actual max id
606 * or lun (e.g. 8 for SCSI parallel systems).
607 */
608 unsigned int max_channel;
609 unsigned int max_id;
610 u64 max_lun;
611
612 /*
613 * This is a unique identifier that must be assigned so that we
614 * have some way of identifying each detected host adapter properly
615 * and uniquely. For hosts that do not support more than one card
616 * in the system at one time, this does not need to be set. It is
617 * initialized to 0 in scsi_register.
618 */
619 unsigned int unique_id;
620
621 /*
622 * The maximum length of SCSI commands that this host can accept.
623 * Probably 12 for most host adapters, but could be 16 for others.
624 * or 260 if the driver supports variable length cdbs.
625 * For drivers that don't set this field, a value of 12 is
626 * assumed.
627 */
628 unsigned short max_cmd_len;
629
630 int this_id;
631 int can_queue;
632 short cmd_per_lun;
633 short unsigned int sg_tablesize;
634 short unsigned int sg_prot_tablesize;
635 unsigned int max_sectors;
636 unsigned int max_segment_size;
637 unsigned long dma_boundary;
638 unsigned long virt_boundary_mask;
639 /*
640 * In scsi-mq mode, the number of hardware queues supported by the LLD.
641 *
642 * Note: it is assumed that each hardware queue has a queue depth of
643 * can_queue. In other words, the total queue depth per host
644 * is nr_hw_queues * can_queue. However, for when host_tagset is set,
645 * the total queue depth is can_queue.
646 */
647 unsigned nr_hw_queues;
648 unsigned nr_maps;
649 unsigned active_mode:2;
650 unsigned unchecked_isa_dma:1;
651
652 /*
653 * Host has requested that no further requests come through for the
654 * time being.
655 */
656 unsigned host_self_blocked:1;
657
658 /*
659 * Host uses correct SCSI ordering not PC ordering. The bit is
660 * set for the minority of drivers whose authors actually read
661 * the spec ;).
662 */
663 unsigned reverse_ordering:1;
664
665 /* Task mgmt function in progress */
666 unsigned tmf_in_progress:1;
667
668 /* Asynchronous scan in progress */
669 unsigned async_scan:1;
670
671 /* Don't resume host in EH */
672 unsigned eh_noresume:1;
673
674 /* The controller does not support WRITE SAME */
675 unsigned no_write_same:1;
676
677 /* True if the host uses host-wide tagspace */
678 unsigned host_tagset:1;
679
680 /* Host responded with short (<36 bytes) INQUIRY result */
681 unsigned short_inquiry:1;
682
683 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
684 unsigned no_scsi2_lun_in_cdb:1;
685
686 /*
687 * Optional work queue to be utilized by the transport
688 */
689 char work_q_name[20];
690 struct workqueue_struct *work_q;
691
692 /*
693 * Task management function work queue
694 */
695 struct workqueue_struct *tmf_work_q;
696
697 /*
698 * Value host_blocked counts down from
699 */
700 unsigned int max_host_blocked;
701
702 /* Protection Information */
703 unsigned int prot_capabilities;
704 unsigned char prot_guard_type;
705
706 /* legacy crap */
707 unsigned long base;
708 unsigned long io_port;
709 unsigned char n_io_port;
710 unsigned char dma_channel;
711 unsigned int irq;
712
713
714 enum scsi_host_state shost_state;
715
716 /* ldm bits */
717 struct device shost_gendev, shost_dev;
718
719 /*
720 * Points to the transport data (if any) which is allocated
721 * separately
722 */
723 void *shost_data;
724
725 /*
726 * Points to the physical bus device we'd use to do DMA
727 * Needed just in case we have virtual hosts.
728 */
729 struct device *dma_dev;
730
731 ANDROID_KABI_RESERVE(1);
732
733 /*
734 * We should ensure that this is aligned, both for better performance
735 * and also because some compilers (m68k) don't automatically force
736 * alignment to a long boundary.
737 */
738 unsigned long hostdata[] /* Used for storage of host specific stuff */
739 __attribute__ ((aligned (sizeof(unsigned long))));
740 };
741
742 #define class_to_shost(d) \
743 container_of(d, struct Scsi_Host, shost_dev)
744
745 #define shost_printk(prefix, shost, fmt, a...) \
746 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
747
shost_priv(struct Scsi_Host * shost)748 static inline void *shost_priv(struct Scsi_Host *shost)
749 {
750 return (void *)shost->hostdata;
751 }
752
753 int scsi_is_host_device(const struct device *);
754
dev_to_shost(struct device * dev)755 static inline struct Scsi_Host *dev_to_shost(struct device *dev)
756 {
757 while (!scsi_is_host_device(dev)) {
758 if (!dev->parent)
759 return NULL;
760 dev = dev->parent;
761 }
762 return container_of(dev, struct Scsi_Host, shost_gendev);
763 }
764
scsi_host_in_recovery(struct Scsi_Host * shost)765 static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
766 {
767 return shost->shost_state == SHOST_RECOVERY ||
768 shost->shost_state == SHOST_CANCEL_RECOVERY ||
769 shost->shost_state == SHOST_DEL_RECOVERY ||
770 shost->tmf_in_progress;
771 }
772
773 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
774 extern void scsi_flush_work(struct Scsi_Host *);
775
776 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
777 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
778 struct device *,
779 struct device *);
780 extern void scsi_scan_host(struct Scsi_Host *);
781 extern void scsi_rescan_device(struct device *);
782 extern void scsi_remove_host(struct Scsi_Host *);
783 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
784 extern int scsi_host_busy(struct Scsi_Host *shost);
785 extern void scsi_host_put(struct Scsi_Host *t);
786 extern struct Scsi_Host *scsi_host_lookup(unsigned short);
787 extern const char *scsi_host_state_name(enum scsi_host_state);
788 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,
789 int status);
790
scsi_add_host(struct Scsi_Host * host,struct device * dev)791 static inline int __must_check scsi_add_host(struct Scsi_Host *host,
792 struct device *dev)
793 {
794 return scsi_add_host_with_dma(host, dev, dev);
795 }
796
scsi_get_device(struct Scsi_Host * shost)797 static inline struct device *scsi_get_device(struct Scsi_Host *shost)
798 {
799 return shost->shost_gendev.parent;
800 }
801
802 /**
803 * scsi_host_scan_allowed - Is scanning of this host allowed
804 * @shost: Pointer to Scsi_Host.
805 **/
scsi_host_scan_allowed(struct Scsi_Host * shost)806 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
807 {
808 return shost->shost_state == SHOST_RUNNING ||
809 shost->shost_state == SHOST_RECOVERY;
810 }
811
812 extern void scsi_unblock_requests(struct Scsi_Host *);
813 extern void scsi_block_requests(struct Scsi_Host *);
814 extern int scsi_host_block(struct Scsi_Host *shost);
815 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
816
817 void scsi_host_busy_iter(struct Scsi_Host *,
818 bool (*fn)(struct scsi_cmnd *, void *, bool), void *priv);
819
820 struct class_container;
821
822 /*
823 * These two functions are used to allocate and free a pseudo device
824 * which will connect to the host adapter itself rather than any
825 * physical device. You must deallocate when you are done with the
826 * thing. This physical pseudo-device isn't real and won't be available
827 * from any high-level drivers.
828 */
829 extern void scsi_free_host_dev(struct scsi_device *);
830 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
831
832 /*
833 * DIF defines the exchange of protection information between
834 * initiator and SBC block device.
835 *
836 * DIX defines the exchange of protection information between OS and
837 * initiator.
838 */
839 enum scsi_host_prot_capabilities {
840 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
841 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
842 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
843
844 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
845 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
846 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
847 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
848 };
849
850 /*
851 * SCSI hosts which support the Data Integrity Extensions must
852 * indicate their capabilities by setting the prot_capabilities using
853 * this call.
854 */
scsi_host_set_prot(struct Scsi_Host * shost,unsigned int mask)855 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
856 {
857 shost->prot_capabilities = mask;
858 }
859
scsi_host_get_prot(struct Scsi_Host * shost)860 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
861 {
862 return shost->prot_capabilities;
863 }
864
scsi_host_prot_dma(struct Scsi_Host * shost)865 static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
866 {
867 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
868 }
869
scsi_host_dif_capable(struct Scsi_Host * shost,unsigned int target_type)870 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
871 {
872 static unsigned char cap[] = { 0,
873 SHOST_DIF_TYPE1_PROTECTION,
874 SHOST_DIF_TYPE2_PROTECTION,
875 SHOST_DIF_TYPE3_PROTECTION };
876
877 if (target_type >= ARRAY_SIZE(cap))
878 return 0;
879
880 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
881 }
882
scsi_host_dix_capable(struct Scsi_Host * shost,unsigned int target_type)883 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
884 {
885 #if defined(CONFIG_BLK_DEV_INTEGRITY)
886 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
887 SHOST_DIX_TYPE1_PROTECTION,
888 SHOST_DIX_TYPE2_PROTECTION,
889 SHOST_DIX_TYPE3_PROTECTION };
890
891 if (target_type >= ARRAY_SIZE(cap))
892 return 0;
893
894 return shost->prot_capabilities & cap[target_type];
895 #endif
896 return 0;
897 }
898
899 /*
900 * All DIX-capable initiators must support the T10-mandated CRC
901 * checksum. Controllers can optionally implement the IP checksum
902 * scheme which has much lower impact on system performance. Note
903 * that the main rationale for the checksum is to match integrity
904 * metadata with data. Detecting bit errors are a job for ECC memory
905 * and buses.
906 */
907
908 enum scsi_host_guard_type {
909 SHOST_DIX_GUARD_CRC = 1 << 0,
910 SHOST_DIX_GUARD_IP = 1 << 1,
911 };
912
scsi_host_set_guard(struct Scsi_Host * shost,unsigned char type)913 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
914 {
915 shost->prot_guard_type = type;
916 }
917
scsi_host_get_guard(struct Scsi_Host * shost)918 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
919 {
920 return shost->prot_guard_type;
921 }
922
923 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
924
925 #endif /* _SCSI_SCSI_HOST_H */
926