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