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_transport_template;
24
25
26 #define SG_ALL SG_CHUNK_SIZE
27
28 #define MODE_UNKNOWN 0x00
29 #define MODE_INITIATOR 0x01
30 #define MODE_TARGET 0x02
31
32 /**
33 * enum scsi_timeout_action - How to handle a command that timed out.
34 * @SCSI_EH_DONE: The command has already been completed.
35 * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion.
36 * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command.
37 */
38 enum scsi_timeout_action {
39 SCSI_EH_DONE,
40 SCSI_EH_RESET_TIMER,
41 SCSI_EH_NOT_HANDLED,
42 };
43
44 struct scsi_host_template {
45 /*
46 * Put fields referenced in IO submission path together in
47 * same cacheline
48 */
49
50 /*
51 * Additional per-command data allocated for the driver.
52 */
53 unsigned int cmd_size;
54
55 /*
56 * The queuecommand function is used to queue up a scsi
57 * command block to the LLDD. When the driver finished
58 * processing the command the done callback is invoked.
59 *
60 * If queuecommand returns 0, then the driver has accepted the
61 * command. It must also push it to the HBA if the scsi_cmnd
62 * flag SCMD_LAST is set, or if the driver does not implement
63 * commit_rqs. The done() function must be called on the command
64 * when the driver has finished with it. (you may call done on the
65 * command before queuecommand returns, but in this case you
66 * *must* return 0 from queuecommand).
67 *
68 * Queuecommand may also reject the command, in which case it may
69 * not touch the command and must not call done() for it.
70 *
71 * There are two possible rejection returns:
72 *
73 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
74 * allow commands to other devices serviced by this host.
75 *
76 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
77 * host temporarily.
78 *
79 * For compatibility, any other non-zero return is treated the
80 * same as SCSI_MLQUEUE_HOST_BUSY.
81 *
82 * NOTE: "temporarily" means either until the next command for#
83 * this device/host completes, or a period of time determined by
84 * I/O pressure in the system if there are no other outstanding
85 * commands.
86 *
87 * STATUS: REQUIRED
88 */
89 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
90
91 /*
92 * The commit_rqs function is used to trigger a hardware
93 * doorbell after some requests have been queued with
94 * queuecommand, when an error is encountered before sending
95 * the request with SCMD_LAST set.
96 *
97 * STATUS: OPTIONAL
98 */
99 void (*commit_rqs)(struct Scsi_Host *, u16);
100
101 struct module *module;
102 const char *name;
103
104 /*
105 * The info function will return whatever useful information the
106 * developer sees fit. If not provided, then the name field will
107 * be used instead.
108 *
109 * Status: OPTIONAL
110 */
111 const char *(*info)(struct Scsi_Host *);
112
113 /*
114 * Ioctl interface
115 *
116 * Status: OPTIONAL
117 */
118 int (*ioctl)(struct scsi_device *dev, unsigned int cmd,
119 void __user *arg);
120
121
122 #ifdef CONFIG_COMPAT
123 /*
124 * Compat handler. Handle 32bit ABI.
125 * When unknown ioctl is passed return -ENOIOCTLCMD.
126 *
127 * Status: OPTIONAL
128 */
129 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,
130 void __user *arg);
131 #endif
132
133 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
134 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
135
136 /*
137 * This is an error handling strategy routine. You don't need to
138 * define one of these if you don't want to - there is a default
139 * routine that is present that should work in most cases. For those
140 * driver authors that have the inclination and ability to write their
141 * own strategy routine, this is where it is specified. Note - the
142 * strategy routine is *ALWAYS* run in the context of the kernel eh
143 * thread. Thus you are guaranteed to *NOT* be in an interrupt
144 * handler when you execute this, and you are also guaranteed to
145 * *NOT* have any other commands being queued while you are in the
146 * strategy routine. When you return from this function, operations
147 * return to normal.
148 *
149 * See scsi_error.c scsi_unjam_host for additional comments about
150 * what this function should and should not be attempting to do.
151 *
152 * Status: REQUIRED (at least one of them)
153 */
154 int (* eh_abort_handler)(struct scsi_cmnd *);
155 int (* eh_device_reset_handler)(struct scsi_cmnd *);
156 int (* eh_target_reset_handler)(struct scsi_cmnd *);
157 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
158 int (* eh_host_reset_handler)(struct scsi_cmnd *);
159
160 /*
161 * Before the mid layer attempts to scan for a new device where none
162 * currently exists, it will call this entry in your driver. Should
163 * your driver need to allocate any structs or perform any other init
164 * items in order to send commands to a currently unused target/lun
165 * combo, then this is where you can perform those allocations. This
166 * is specifically so that drivers won't have to perform any kind of
167 * "is this a new device" checks in their queuecommand routine,
168 * thereby making the hot path a bit quicker.
169 *
170 * Return values: 0 on success, non-0 on failure
171 *
172 * Deallocation: If we didn't find any devices at this ID, you will
173 * get an immediate call to slave_destroy(). If we find something
174 * here then you will get a call to slave_configure(), then the
175 * device will be used for however long it is kept around, then when
176 * the device is removed from the system (or * possibly at reboot
177 * time), you will then get a call to slave_destroy(). This is
178 * assuming you implement slave_configure and slave_destroy.
179 * However, if you allocate memory and hang it off the device struct,
180 * then you must implement the slave_destroy() routine at a minimum
181 * in order to avoid leaking memory
182 * each time a device is tore down.
183 *
184 * Status: OPTIONAL
185 */
186 int (* slave_alloc)(struct scsi_device *);
187
188 /*
189 * Once the device has responded to an INQUIRY and we know the
190 * device is online, we call into the low level driver with the
191 * struct scsi_device *. If the low level device driver implements
192 * this function, it *must* perform the task of setting the queue
193 * depth on the device. All other tasks are optional and depend
194 * on what the driver supports and various implementation details.
195 *
196 * Things currently recommended to be handled at this time include:
197 *
198 * 1. Setting the device queue depth. Proper setting of this is
199 * described in the comments for scsi_change_queue_depth.
200 * 2. Determining if the device supports the various synchronous
201 * negotiation protocols. The device struct will already have
202 * responded to INQUIRY and the results of the standard items
203 * will have been shoved into the various device flag bits, eg.
204 * device->sdtr will be true if the device supports SDTR messages.
205 * 3. Allocating command structs that the device will need.
206 * 4. Setting the default timeout on this device (if needed).
207 * 5. Anything else the low level driver might want to do on a device
208 * specific setup basis...
209 * 6. Return 0 on success, non-0 on error. The device will be marked
210 * as offline on error so that no access will occur. If you return
211 * non-0, your slave_destroy routine will never get called for this
212 * device, so don't leave any loose memory hanging around, clean
213 * up after yourself before returning non-0
214 *
215 * Status: OPTIONAL
216 */
217 int (* slave_configure)(struct scsi_device *);
218
219 /*
220 * Immediately prior to deallocating the device and after all activity
221 * has ceased the mid layer calls this point so that the low level
222 * driver may completely detach itself from the scsi device and vice
223 * versa. The low level driver is responsible for freeing any memory
224 * it allocated in the slave_alloc or slave_configure calls.
225 *
226 * Status: OPTIONAL
227 */
228 void (* slave_destroy)(struct scsi_device *);
229
230 /*
231 * Before the mid layer attempts to scan for a new device attached
232 * to a target where no target currently exists, it will call this
233 * entry in your driver. Should your driver need to allocate any
234 * structs or perform any other init items in order to send commands
235 * to a currently unused target, then this is where you can perform
236 * those allocations.
237 *
238 * Return values: 0 on success, non-0 on failure
239 *
240 * Status: OPTIONAL
241 */
242 int (* target_alloc)(struct scsi_target *);
243
244 /*
245 * Immediately prior to deallocating the target structure, and
246 * after all activity to attached scsi devices has ceased, the
247 * midlayer calls this point so that the driver may deallocate
248 * and terminate any references to the target.
249 *
250 * Status: OPTIONAL
251 */
252 void (* target_destroy)(struct scsi_target *);
253
254 /*
255 * If a host has the ability to discover targets on its own instead
256 * of scanning the entire bus, it can fill in this function and
257 * call scsi_scan_host(). This function will be called periodically
258 * until it returns 1 with the scsi_host and the elapsed time of
259 * the scan in jiffies.
260 *
261 * Status: OPTIONAL
262 */
263 int (* scan_finished)(struct Scsi_Host *, unsigned long);
264
265 /*
266 * If the host wants to be called before the scan starts, but
267 * after the midlayer has set up ready for the scan, it can fill
268 * in this function.
269 *
270 * Status: OPTIONAL
271 */
272 void (* scan_start)(struct Scsi_Host *);
273
274 /*
275 * Fill in this function to allow the queue depth of this host
276 * to be changeable (on a per device basis). Returns either
277 * the current queue depth setting (may be different from what
278 * was passed in) or an error. An error should only be
279 * returned if the requested depth is legal but the driver was
280 * unable to set it. If the requested depth is illegal, the
281 * driver should set and return the closest legal queue depth.
282 *
283 * Status: OPTIONAL
284 */
285 int (* change_queue_depth)(struct scsi_device *, int);
286
287 /*
288 * This functions lets the driver expose the queue mapping
289 * to the block layer.
290 *
291 * Status: OPTIONAL
292 */
293 int (* map_queues)(struct Scsi_Host *shost);
294
295 /*
296 * SCSI interface of blk_poll - poll for IO completions.
297 * Only applicable if SCSI LLD exposes multiple h/w queues.
298 *
299 * Return value: Number of completed entries found.
300 *
301 * Status: OPTIONAL
302 */
303 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num);
304
305 /*
306 * Check if scatterlists need to be padded for DMA draining.
307 *
308 * Status: OPTIONAL
309 */
310 bool (* dma_need_drain)(struct request *rq);
311
312 /*
313 * This function determines the BIOS parameters for a given
314 * harddisk. These tend to be numbers that are made up by
315 * the host adapter. Parameters:
316 * size, device, list (heads, sectors, cylinders)
317 *
318 * Status: OPTIONAL
319 */
320 int (* bios_param)(struct scsi_device *, struct block_device *,
321 sector_t, int []);
322
323 /*
324 * This function is called when one or more partitions on the
325 * device reach beyond the end of the device.
326 *
327 * Status: OPTIONAL
328 */
329 void (*unlock_native_capacity)(struct scsi_device *);
330
331 /*
332 * Can be used to export driver statistics and other infos to the
333 * world outside the kernel ie. userspace and it also provides an
334 * interface to feed the driver with information.
335 *
336 * Status: OBSOLETE
337 */
338 int (*show_info)(struct seq_file *, struct Scsi_Host *);
339 int (*write_info)(struct Scsi_Host *, char *, int);
340
341 /*
342 * This is an optional routine that allows the transport to become
343 * involved when a scsi io timer fires. The return value tells the
344 * timer routine how to finish the io timeout handling.
345 *
346 * Status: OPTIONAL
347 */
348 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *);
349 /*
350 * Optional routine that allows the transport to decide if a cmd
351 * is retryable. Return true if the transport is in a state the
352 * cmd should be retried on.
353 */
354 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd);
355
356 /* This is an optional routine that allows transport to initiate
357 * LLD adapter or firmware reset using sysfs attribute.
358 *
359 * Return values: 0 on success, -ve value on failure.
360 *
361 * Status: OPTIONAL
362 */
363
364 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
365 #define SCSI_ADAPTER_RESET 1
366 #define SCSI_FIRMWARE_RESET 2
367
368
369 /*
370 * Name of proc directory
371 */
372 const char *proc_name;
373
374 /*
375 * Used to store the procfs directory if a driver implements the
376 * show_info method.
377 */
378 struct proc_dir_entry *proc_dir;
379
380 /*
381 * This determines if we will use a non-interrupt driven
382 * or an interrupt driven scheme. It is set to the maximum number
383 * of simultaneous commands a single hw queue in HBA will accept.
384 */
385 int can_queue;
386
387 /*
388 * In many instances, especially where disconnect / reconnect are
389 * supported, our host also has an ID on the SCSI bus. If this is
390 * the case, then it must be reserved. Please set this_id to -1 if
391 * your setup is in single initiator mode, and the host lacks an
392 * ID.
393 */
394 int this_id;
395
396 /*
397 * This determines the degree to which the host adapter is capable
398 * of scatter-gather.
399 */
400 unsigned short sg_tablesize;
401 unsigned short sg_prot_tablesize;
402
403 /*
404 * Set this if the host adapter has limitations beside segment count.
405 */
406 unsigned int max_sectors;
407
408 /*
409 * Maximum size in bytes of a single segment.
410 */
411 unsigned int max_segment_size;
412
413 /*
414 * DMA scatter gather segment boundary limit. A segment crossing this
415 * boundary will be split in two.
416 */
417 unsigned long dma_boundary;
418
419 unsigned long virt_boundary_mask;
420
421 /*
422 * This specifies "machine infinity" for host templates which don't
423 * limit the transfer size. Note this limit represents an absolute
424 * maximum, and may be over the transfer limits allowed for
425 * individual devices (e.g. 256 for SCSI-1).
426 */
427 #define SCSI_DEFAULT_MAX_SECTORS 1024
428
429 /*
430 * True if this host adapter can make good use of linked commands.
431 * This will allow more than one command to be queued to a given
432 * unit on a given host. Set this to the maximum number of command
433 * blocks to be provided for each device. Set this to 1 for one
434 * command block per lun, 2 for two, etc. Do not set this to 0.
435 * You should make sure that the host adapter will do the right thing
436 * before you try setting this above 1.
437 */
438 short cmd_per_lun;
439
440 /*
441 * present contains counter indicating how many boards of this
442 * type were found when we did the scan.
443 */
444 unsigned char present;
445
446 /* If use block layer to manage tags, this is tag allocation policy */
447 int tag_alloc_policy;
448
449 /*
450 * Track QUEUE_FULL events and reduce queue depth on demand.
451 */
452 unsigned track_queue_depth:1;
453
454 /*
455 * This specifies the mode that a LLD supports.
456 */
457 unsigned supported_mode:2;
458
459 /*
460 * True for emulated SCSI host adapters (e.g. ATAPI).
461 */
462 unsigned emulated:1;
463
464 /*
465 * True if the low-level driver performs its own reset-settle delays.
466 */
467 unsigned skip_settle_delay:1;
468
469 /* True if the controller does not support WRITE SAME */
470 unsigned no_write_same:1;
471
472 /* True if the host uses host-wide tagspace */
473 unsigned host_tagset:1;
474
475 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
476 unsigned queuecommand_may_block:1;
477
478 /*
479 * Countdown for host blocking with no commands outstanding.
480 */
481 unsigned int max_host_blocked;
482
483 /*
484 * Default value for the blocking. If the queue is empty,
485 * host_blocked counts down in the request_fn until it restarts
486 * host operations as zero is reached.
487 *
488 * FIXME: This should probably be a value in the template
489 */
490 #define SCSI_DEFAULT_HOST_BLOCKED 7
491
492 /*
493 * Pointer to the sysfs class properties for this host, NULL terminated.
494 */
495 struct device_attribute **shost_attrs;
496
497 /*
498 * Pointer to the SCSI device properties for this host, NULL terminated.
499 */
500 struct device_attribute **sdev_attrs;
501
502 /*
503 * Pointer to the SCSI device attribute groups for this host,
504 * NULL terminated.
505 */
506 const struct attribute_group **sdev_groups;
507
508 /*
509 * Vendor Identifier associated with the host
510 *
511 * Note: When specifying vendor_id, be sure to read the
512 * Vendor Type and ID formatting requirements specified in
513 * scsi_netlink.h
514 */
515 u64 vendor_id;
516
517 struct scsi_host_cmd_pool *cmd_pool;
518
519 /* Delay for runtime autosuspend */
520 int rpm_autosuspend_delay;
521
522 ANDROID_KABI_RESERVE(1);
523 ANDROID_KABI_RESERVE(2);
524 ANDROID_KABI_RESERVE(3);
525 ANDROID_KABI_RESERVE(4);
526 };
527
528 /*
529 * Temporary #define for host lock push down. Can be removed when all
530 * drivers have been updated to take advantage of unlocked
531 * queuecommand.
532 *
533 */
534 #define DEF_SCSI_QCMD(func_name) \
535 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
536 { \
537 unsigned long irq_flags; \
538 int rc; \
539 spin_lock_irqsave(shost->host_lock, irq_flags); \
540 rc = func_name##_lck (cmd, cmd->scsi_done); \
541 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
542 return rc; \
543 }
544
545
546 /*
547 * shost state: If you alter this, you also need to alter scsi_sysfs.c
548 * (for the ascii descriptions) and the state model enforcer:
549 * scsi_host_set_state()
550 */
551 enum scsi_host_state {
552 SHOST_CREATED = 1,
553 SHOST_RUNNING,
554 SHOST_CANCEL,
555 SHOST_DEL,
556 SHOST_RECOVERY,
557 SHOST_CANCEL_RECOVERY,
558 SHOST_DEL_RECOVERY,
559 };
560
561 struct Scsi_Host {
562 /*
563 * __devices is protected by the host_lock, but you should
564 * usually use scsi_device_lookup / shost_for_each_device
565 * to access it and don't care about locking yourself.
566 * In the rare case of being in irq context you can use
567 * their __ prefixed variants with the lock held. NEVER
568 * access this list directly from a driver.
569 */
570 struct list_head __devices;
571 struct list_head __targets;
572
573 struct list_head starved_list;
574
575 spinlock_t default_lock;
576 spinlock_t *host_lock;
577
578 struct mutex scan_mutex;/* serialize scanning activity */
579
580 struct list_head eh_abort_list;
581 struct list_head eh_cmd_q;
582 struct task_struct * ehandler; /* Error recovery thread. */
583 struct completion * eh_action; /* Wait for specific actions on the
584 host. */
585 wait_queue_head_t host_wait;
586 struct scsi_host_template *hostt;
587 struct scsi_transport_template *transportt;
588
589 /* Area to keep a shared tag map */
590 struct blk_mq_tag_set tag_set;
591
592 atomic_t host_blocked;
593
594 unsigned int host_failed; /* commands that failed.
595 protected by host_lock */
596 unsigned int host_eh_scheduled; /* EH scheduled without command */
597
598 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
599
600 /* next two fields are used to bound the time spent in error handling */
601 int eh_deadline;
602 unsigned long last_reset;
603
604
605 /*
606 * These three parameters can be used to allow for wide scsi,
607 * and for host adapters that support multiple busses
608 * The last two should be set to 1 more than the actual max id
609 * or lun (e.g. 8 for SCSI parallel systems).
610 */
611 unsigned int max_channel;
612 unsigned int max_id;
613 u64 max_lun;
614
615 /*
616 * This is a unique identifier that must be assigned so that we
617 * have some way of identifying each detected host adapter properly
618 * and uniquely. For hosts that do not support more than one card
619 * in the system at one time, this does not need to be set. It is
620 * initialized to 0 in scsi_register.
621 */
622 unsigned int unique_id;
623
624 /*
625 * The maximum length of SCSI commands that this host can accept.
626 * Probably 12 for most host adapters, but could be 16 for others.
627 * or 260 if the driver supports variable length cdbs.
628 * For drivers that don't set this field, a value of 12 is
629 * assumed.
630 */
631 unsigned short max_cmd_len;
632
633 int this_id;
634 int can_queue;
635 short cmd_per_lun;
636 short unsigned int sg_tablesize;
637 short unsigned int sg_prot_tablesize;
638 unsigned int max_sectors;
639 unsigned int max_segment_size;
640 unsigned long dma_boundary;
641 unsigned long virt_boundary_mask;
642 /*
643 * In scsi-mq mode, the number of hardware queues supported by the LLD.
644 *
645 * Note: it is assumed that each hardware queue has a queue depth of
646 * can_queue. In other words, the total queue depth per host
647 * is nr_hw_queues * can_queue. However, for when host_tagset is set,
648 * the total queue depth is can_queue.
649 */
650 unsigned nr_hw_queues;
651 unsigned nr_maps;
652 unsigned active_mode:2;
653
654 /*
655 * Host has requested that no further requests come through for the
656 * time being.
657 */
658 unsigned host_self_blocked:1;
659
660 /*
661 * Host uses correct SCSI ordering not PC ordering. The bit is
662 * set for the minority of drivers whose authors actually read
663 * the spec ;).
664 */
665 unsigned reverse_ordering:1;
666
667 /* Task mgmt function in progress */
668 unsigned tmf_in_progress:1;
669
670 /* Asynchronous scan in progress */
671 unsigned async_scan:1;
672
673 /* Don't resume host in EH */
674 unsigned eh_noresume:1;
675
676 /* The controller does not support WRITE SAME */
677 unsigned no_write_same:1;
678
679 /* True if the host uses host-wide tagspace */
680 unsigned host_tagset:1;
681
682 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
683 unsigned queuecommand_may_block:1;
684
685 /* Host responded with short (<36 bytes) INQUIRY result */
686 unsigned short_inquiry:1;
687
688 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
689 unsigned no_scsi2_lun_in_cdb:1;
690
691 /*
692 * Optional work queue to be utilized by the transport
693 */
694 char work_q_name[20];
695 struct workqueue_struct *work_q;
696
697 /*
698 * Task management function work queue
699 */
700 struct workqueue_struct *tmf_work_q;
701
702 /*
703 * Value host_blocked counts down from
704 */
705 unsigned int max_host_blocked;
706
707 /* Protection Information */
708 unsigned int prot_capabilities;
709 unsigned char prot_guard_type;
710
711 /* legacy crap */
712 unsigned long base;
713 unsigned long io_port;
714 unsigned char n_io_port;
715 unsigned char dma_channel;
716 unsigned int irq;
717
718
719 enum scsi_host_state shost_state;
720
721 /* ldm bits */
722 struct device shost_gendev, shost_dev;
723
724 /*
725 * Points to the transport data (if any) which is allocated
726 * separately
727 */
728 void *shost_data;
729
730 /*
731 * Points to the physical bus device we'd use to do DMA
732 * Needed just in case we have virtual hosts.
733 */
734 struct device *dma_dev;
735
736 ANDROID_KABI_RESERVE(1);
737
738 /*
739 * We should ensure that this is aligned, both for better performance
740 * and also because some compilers (m68k) don't automatically force
741 * alignment to a long boundary.
742 */
743 unsigned long hostdata[] /* Used for storage of host specific stuff */
744 __attribute__ ((aligned (sizeof(unsigned long))));
745 };
746
747 #define class_to_shost(d) \
748 container_of(d, struct Scsi_Host, shost_dev)
749
750 #define shost_printk(prefix, shost, fmt, a...) \
751 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
752
shost_priv(struct Scsi_Host * shost)753 static inline void *shost_priv(struct Scsi_Host *shost)
754 {
755 return (void *)shost->hostdata;
756 }
757
758 int scsi_is_host_device(const struct device *);
759
dev_to_shost(struct device * dev)760 static inline struct Scsi_Host *dev_to_shost(struct device *dev)
761 {
762 while (!scsi_is_host_device(dev)) {
763 if (!dev->parent)
764 return NULL;
765 dev = dev->parent;
766 }
767 return container_of(dev, struct Scsi_Host, shost_gendev);
768 }
769
scsi_host_in_recovery(struct Scsi_Host * shost)770 static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
771 {
772 return shost->shost_state == SHOST_RECOVERY ||
773 shost->shost_state == SHOST_CANCEL_RECOVERY ||
774 shost->shost_state == SHOST_DEL_RECOVERY ||
775 shost->tmf_in_progress;
776 }
777
778 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
779 extern void scsi_flush_work(struct Scsi_Host *);
780
781 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
782 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
783 struct device *,
784 struct device *);
785 extern void scsi_scan_host(struct Scsi_Host *);
786 extern void scsi_rescan_device(struct device *);
787 extern void scsi_remove_host(struct Scsi_Host *);
788 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
789 extern int scsi_host_busy(struct Scsi_Host *shost);
790 extern void scsi_host_put(struct Scsi_Host *t);
791 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum);
792 extern const char *scsi_host_state_name(enum scsi_host_state);
793 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,
794 enum scsi_host_status status);
795
scsi_add_host(struct Scsi_Host * host,struct device * dev)796 static inline int __must_check scsi_add_host(struct Scsi_Host *host,
797 struct device *dev)
798 {
799 return scsi_add_host_with_dma(host, dev, dev);
800 }
801
scsi_get_device(struct Scsi_Host * shost)802 static inline struct device *scsi_get_device(struct Scsi_Host *shost)
803 {
804 return shost->shost_gendev.parent;
805 }
806
807 /**
808 * scsi_host_scan_allowed - Is scanning of this host allowed
809 * @shost: Pointer to Scsi_Host.
810 **/
scsi_host_scan_allowed(struct Scsi_Host * shost)811 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
812 {
813 return shost->shost_state == SHOST_RUNNING ||
814 shost->shost_state == SHOST_RECOVERY;
815 }
816
817 extern void scsi_unblock_requests(struct Scsi_Host *);
818 extern void scsi_block_requests(struct Scsi_Host *);
819 extern int scsi_host_block(struct Scsi_Host *shost);
820 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
821
822 void scsi_host_busy_iter(struct Scsi_Host *,
823 bool (*fn)(struct scsi_cmnd *, void *, bool), void *priv);
824
825 struct class_container;
826
827 /*
828 * These two functions are used to allocate and free a pseudo device
829 * which will connect to the host adapter itself rather than any
830 * physical device. You must deallocate when you are done with the
831 * thing. This physical pseudo-device isn't real and won't be available
832 * from any high-level drivers.
833 */
834 extern void scsi_free_host_dev(struct scsi_device *);
835 extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
836
837 /*
838 * DIF defines the exchange of protection information between
839 * initiator and SBC block device.
840 *
841 * DIX defines the exchange of protection information between OS and
842 * initiator.
843 */
844 enum scsi_host_prot_capabilities {
845 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
846 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
847 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
848
849 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
850 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
851 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
852 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
853 };
854
855 /*
856 * SCSI hosts which support the Data Integrity Extensions must
857 * indicate their capabilities by setting the prot_capabilities using
858 * this call.
859 */
scsi_host_set_prot(struct Scsi_Host * shost,unsigned int mask)860 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
861 {
862 shost->prot_capabilities = mask;
863 }
864
scsi_host_get_prot(struct Scsi_Host * shost)865 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
866 {
867 return shost->prot_capabilities;
868 }
869
scsi_host_prot_dma(struct Scsi_Host * shost)870 static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
871 {
872 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
873 }
874
scsi_host_dif_capable(struct Scsi_Host * shost,unsigned int target_type)875 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
876 {
877 static unsigned char cap[] = { 0,
878 SHOST_DIF_TYPE1_PROTECTION,
879 SHOST_DIF_TYPE2_PROTECTION,
880 SHOST_DIF_TYPE3_PROTECTION };
881
882 if (target_type >= ARRAY_SIZE(cap))
883 return 0;
884
885 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
886 }
887
scsi_host_dix_capable(struct Scsi_Host * shost,unsigned int target_type)888 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
889 {
890 #if defined(CONFIG_BLK_DEV_INTEGRITY)
891 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
892 SHOST_DIX_TYPE1_PROTECTION,
893 SHOST_DIX_TYPE2_PROTECTION,
894 SHOST_DIX_TYPE3_PROTECTION };
895
896 if (target_type >= ARRAY_SIZE(cap))
897 return 0;
898
899 return shost->prot_capabilities & cap[target_type];
900 #endif
901 return 0;
902 }
903
904 /*
905 * All DIX-capable initiators must support the T10-mandated CRC
906 * checksum. Controllers can optionally implement the IP checksum
907 * scheme which has much lower impact on system performance. Note
908 * that the main rationale for the checksum is to match integrity
909 * metadata with data. Detecting bit errors are a job for ECC memory
910 * and buses.
911 */
912
913 enum scsi_host_guard_type {
914 SHOST_DIX_GUARD_CRC = 1 << 0,
915 SHOST_DIX_GUARD_IP = 1 << 1,
916 };
917
scsi_host_set_guard(struct Scsi_Host * shost,unsigned char type)918 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
919 {
920 shost->prot_guard_type = type;
921 }
922
scsi_host_get_guard(struct Scsi_Host * shost)923 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
924 {
925 return shost->prot_guard_type;
926 }
927
928 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
929
930 #endif /* _SCSI_SCSI_HOST_H */
931