xref: /linux/include/scsi/scsi_device.h (revision ae22a94997b8a03dcb3c922857c203246711f9d4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _SCSI_SCSI_DEVICE_H
3 #define _SCSI_SCSI_DEVICE_H
4 
5 #include <linux/list.h>
6 #include <linux/spinlock.h>
7 #include <linux/workqueue.h>
8 #include <linux/blk-mq.h>
9 #include <scsi/scsi.h>
10 #include <linux/atomic.h>
11 #include <linux/sbitmap.h>
12 
13 struct bsg_device;
14 struct device;
15 struct request_queue;
16 struct scsi_cmnd;
17 struct scsi_lun;
18 struct scsi_sense_hdr;
19 
20 typedef __u64 __bitwise blist_flags_t;
21 
22 #define SCSI_SENSE_BUFFERSIZE	96
23 
24 struct scsi_mode_data {
25 	__u32	length;
26 	__u16	block_descriptor_length;
27 	__u8	medium_type;
28 	__u8	device_specific;
29 	__u8	header_length;
30 	__u8	longlba:1;
31 };
32 
33 /*
34  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
35  * (for the ascii descriptions) and the state model enforcer:
36  * scsi_lib:scsi_device_set_state().
37  */
38 enum scsi_device_state {
39 	SDEV_CREATED = 1,	/* device created but not added to sysfs
40 				 * Only internal commands allowed (for inq) */
41 	SDEV_RUNNING,		/* device properly configured
42 				 * All commands allowed */
43 	SDEV_CANCEL,		/* beginning to delete device
44 				 * Only error handler commands allowed */
45 	SDEV_DEL,		/* device deleted
46 				 * no commands allowed */
47 	SDEV_QUIESCE,		/* Device quiescent.  No block commands
48 				 * will be accepted, only specials (which
49 				 * originate in the mid-layer) */
50 	SDEV_OFFLINE,		/* Device offlined (by error handling or
51 				 * user request */
52 	SDEV_TRANSPORT_OFFLINE,	/* Offlined by transport class error handler */
53 	SDEV_BLOCK,		/* Device blocked by scsi lld.  No
54 				 * scsi commands from user or midlayer
55 				 * should be issued to the scsi
56 				 * lld. */
57 	SDEV_CREATED_BLOCK,	/* same as above but for created devices */
58 };
59 
60 enum scsi_scan_mode {
61 	SCSI_SCAN_INITIAL = 0,
62 	SCSI_SCAN_RESCAN,
63 	SCSI_SCAN_MANUAL,
64 };
65 
66 enum scsi_device_event {
67 	SDEV_EVT_MEDIA_CHANGE	= 1,	/* media has changed */
68 	SDEV_EVT_INQUIRY_CHANGE_REPORTED,		/* 3F 03  UA reported */
69 	SDEV_EVT_CAPACITY_CHANGE_REPORTED,		/* 2A 09  UA reported */
70 	SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,	/* 38 07  UA reported */
71 	SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,	/* 2A 01  UA reported */
72 	SDEV_EVT_LUN_CHANGE_REPORTED,			/* 3F 0E  UA reported */
73 	SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,		/* 2A 06  UA reported */
74 	SDEV_EVT_POWER_ON_RESET_OCCURRED,		/* 29 00  UA reported */
75 
76 	SDEV_EVT_FIRST		= SDEV_EVT_MEDIA_CHANGE,
77 	SDEV_EVT_LAST		= SDEV_EVT_POWER_ON_RESET_OCCURRED,
78 
79 	SDEV_EVT_MAXBITS	= SDEV_EVT_LAST + 1
80 };
81 
82 struct scsi_event {
83 	enum scsi_device_event	evt_type;
84 	struct list_head	node;
85 
86 	/* put union of data structures, for non-simple event types,
87 	 * here
88 	 */
89 };
90 
91 /**
92  * struct scsi_vpd - SCSI Vital Product Data
93  * @rcu: For kfree_rcu().
94  * @len: Length in bytes of @data.
95  * @data: VPD data as defined in various T10 SCSI standard documents.
96  */
97 struct scsi_vpd {
98 	struct rcu_head	rcu;
99 	int		len;
100 	unsigned char	data[];
101 };
102 
103 struct scsi_device {
104 	struct Scsi_Host *host;
105 	struct request_queue *request_queue;
106 
107 	/* the next two are protected by the host->host_lock */
108 	struct list_head    siblings;   /* list of all devices on this host */
109 	struct list_head    same_target_siblings; /* just the devices sharing same target id */
110 
111 	struct sbitmap budget_map;
112 	atomic_t device_blocked;	/* Device returned QUEUE_FULL. */
113 
114 	atomic_t restarts;
115 	spinlock_t list_lock;
116 	struct list_head starved_entry;
117 	unsigned short queue_depth;	/* How deep of a queue we want */
118 	unsigned short max_queue_depth;	/* max queue depth */
119 	unsigned short last_queue_full_depth; /* These two are used by */
120 	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
121 	unsigned long last_queue_full_time;	/* last queue full time */
122 	unsigned long queue_ramp_up_period;	/* ramp up period in jiffies */
123 #define SCSI_DEFAULT_RAMP_UP_PERIOD	(120 * HZ)
124 
125 	unsigned long last_queue_ramp_up;	/* last queue ramp up time */
126 
127 	unsigned int id, channel;
128 	u64 lun;
129 	unsigned int manufacturer;	/* Manufacturer of device, for using
130 					 * vendor-specific cmd's */
131 	unsigned sector_size;	/* size in bytes */
132 
133 	void *hostdata;		/* available to low-level driver */
134 	unsigned char type;
135 	char scsi_level;
136 	char inq_periph_qual;	/* PQ from INQUIRY data */
137 	struct mutex inquiry_mutex;
138 	unsigned char inquiry_len;	/* valid bytes in 'inquiry' */
139 	unsigned char * inquiry;	/* INQUIRY response data */
140 	const char * vendor;		/* [back_compat] point into 'inquiry' ... */
141 	const char * model;		/* ... after scan; point to static string */
142 	const char * rev;		/* ... "nullnullnullnull" before scan */
143 
144 #define SCSI_DEFAULT_VPD_LEN	255	/* default SCSI VPD page size (max) */
145 	struct scsi_vpd __rcu *vpd_pg0;
146 	struct scsi_vpd __rcu *vpd_pg83;
147 	struct scsi_vpd __rcu *vpd_pg80;
148 	struct scsi_vpd __rcu *vpd_pg89;
149 	struct scsi_vpd __rcu *vpd_pgb0;
150 	struct scsi_vpd __rcu *vpd_pgb1;
151 	struct scsi_vpd __rcu *vpd_pgb2;
152 	struct scsi_vpd __rcu *vpd_pgb7;
153 
154 	struct scsi_target      *sdev_target;
155 
156 	blist_flags_t		sdev_bflags; /* black/white flags as also found in
157 				 * scsi_devinfo.[hc]. For now used only to
158 				 * pass settings from slave_alloc to scsi
159 				 * core. */
160 	unsigned int eh_timeout; /* Error handling timeout */
161 
162 	/*
163 	 * If true, let the high-level device driver (sd) manage the device
164 	 * power state for system suspend/resume (suspend to RAM and
165 	 * hibernation) operations.
166 	 */
167 	unsigned manage_system_start_stop:1;
168 
169 	/*
170 	 * If true, let the high-level device driver (sd) manage the device
171 	 * power state for runtime device suspand and resume operations.
172 	 */
173 	unsigned manage_runtime_start_stop:1;
174 
175 	/*
176 	 * If true, let the high-level device driver (sd) manage the device
177 	 * power state for system shutdown (power off) operations.
178 	 */
179 	unsigned manage_shutdown:1;
180 
181 	/*
182 	 * If set and if the device is runtime suspended, ask the high-level
183 	 * device driver (sd) to force a runtime resume of the device.
184 	 */
185 	unsigned force_runtime_start_on_system_start:1;
186 
187 	unsigned removable:1;
188 	unsigned changed:1;	/* Data invalid due to media change */
189 	unsigned busy:1;	/* Used to prevent races */
190 	unsigned lockable:1;	/* Able to prevent media removal */
191 	unsigned locked:1;      /* Media removal disabled */
192 	unsigned borken:1;	/* Tell the Seagate driver to be
193 				 * painfully slow on this device */
194 	unsigned disconnect:1;	/* can disconnect */
195 	unsigned soft_reset:1;	/* Uses soft reset option */
196 	unsigned sdtr:1;	/* Device supports SDTR messages */
197 	unsigned wdtr:1;	/* Device supports WDTR messages */
198 	unsigned ppr:1;		/* Device supports PPR messages */
199 	unsigned tagged_supported:1;	/* Supports SCSI-II tagged queuing */
200 	unsigned simple_tags:1;	/* simple queue tag messages are enabled */
201 	unsigned was_reset:1;	/* There was a bus reset on the bus for
202 				 * this device */
203 	unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
204 				     * because we did a bus reset. */
205 	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
206 	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
207 	unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */
208 	unsigned read_before_ms:1;	/* perform a READ before MODE SENSE */
209 	unsigned no_report_opcodes:1;	/* no REPORT SUPPORTED OPERATION CODES */
210 	unsigned no_write_same:1;	/* no WRITE SAME command */
211 	unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
212 	unsigned use_16_for_sync:1;	/* Use sync (16) over sync (10) */
213 	unsigned skip_ms_page_8:1;	/* do not use MODE SENSE page 0x08 */
214 	unsigned skip_ms_page_3f:1;	/* do not use MODE SENSE page 0x3f */
215 	unsigned skip_vpd_pages:1;	/* do not read VPD pages */
216 	unsigned try_vpd_pages:1;	/* attempt to read VPD pages */
217 	unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
218 	unsigned no_start_on_add:1;	/* do not issue start on add */
219 	unsigned allow_restart:1; /* issue START_UNIT in error handler */
220 	unsigned start_stop_pwr_cond:1;	/* Set power cond. in START_STOP_UNIT */
221 	unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
222 	unsigned select_no_atn:1;
223 	unsigned fix_capacity:1;	/* READ_CAPACITY is too high by 1 */
224 	unsigned guess_capacity:1;	/* READ_CAPACITY might be too high by 1 */
225 	unsigned retry_hwerror:1;	/* Retry HARDWARE_ERROR */
226 	unsigned last_sector_bug:1;	/* do not use multisector accesses on
227 					   SD_LAST_BUGGY_SECTORS */
228 	unsigned no_read_disc_info:1;	/* Avoid READ_DISC_INFO cmds */
229 	unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
230 	unsigned try_rc_10_first:1;	/* Try READ_CAPACACITY_10 first */
231 	unsigned security_supported:1;	/* Supports Security Protocols */
232 	unsigned is_visible:1;	/* is the device visible in sysfs */
233 	unsigned wce_default_on:1;	/* Cache is ON by default */
234 	unsigned no_dif:1;	/* T10 PI (DIF) should be disabled */
235 	unsigned broken_fua:1;		/* Don't set FUA bit */
236 	unsigned lun_in_cdb:1;		/* Store LUN bits in CDB[1] */
237 	unsigned unmap_limit_for_ws:1;	/* Use the UNMAP limit for WRITE SAME */
238 	unsigned rpm_autosuspend:1;	/* Enable runtime autosuspend at device
239 					 * creation time */
240 	unsigned ignore_media_change:1; /* Ignore MEDIA CHANGE on resume */
241 	unsigned silence_suspend:1;	/* Do not print runtime PM related messages */
242 	unsigned no_vpd_size:1;		/* No VPD size reported in header */
243 
244 	unsigned cdl_supported:1;	/* Command duration limits supported */
245 	unsigned cdl_enable:1;		/* Enable/disable Command duration limits */
246 
247 	unsigned int queue_stopped;	/* request queue is quiesced */
248 	bool offline_already;		/* Device offline message logged */
249 
250 	atomic_t disk_events_disable_depth; /* disable depth for disk events */
251 
252 	DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
253 	DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
254 	struct list_head event_list;	/* asserted events */
255 	struct work_struct event_work;
256 
257 	unsigned int max_device_blocked; /* what device_blocked counts down from  */
258 #define SCSI_DEFAULT_DEVICE_BLOCKED	3
259 
260 	atomic_t iorequest_cnt;
261 	atomic_t iodone_cnt;
262 	atomic_t ioerr_cnt;
263 	atomic_t iotmo_cnt;
264 
265 	struct device		sdev_gendev,
266 				sdev_dev;
267 
268 	struct work_struct	requeue_work;
269 
270 	struct scsi_device_handler *handler;
271 	void			*handler_data;
272 
273 	size_t			dma_drain_len;
274 	void			*dma_drain_buf;
275 
276 	unsigned int		sg_timeout;
277 	unsigned int		sg_reserved_size;
278 
279 	struct bsg_device	*bsg_dev;
280 	unsigned char		access_state;
281 	struct mutex		state_mutex;
282 	enum scsi_device_state sdev_state;
283 	struct task_struct	*quiesced_by;
284 	unsigned long		sdev_data[];
285 } __attribute__((aligned(sizeof(unsigned long))));
286 
287 #define	to_scsi_device(d)	\
288 	container_of(d, struct scsi_device, sdev_gendev)
289 #define	class_to_sdev(d)	\
290 	container_of(d, struct scsi_device, sdev_dev)
291 #define transport_class_to_sdev(class_dev) \
292 	to_scsi_device(class_dev->parent)
293 
294 #define sdev_dbg(sdev, fmt, a...) \
295 	dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)
296 
297 /*
298  * like scmd_printk, but the device name is passed in
299  * as a string pointer
300  */
301 __printf(4, 5) void
302 sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
303 		const char *, ...);
304 
305 #define sdev_printk(l, sdev, fmt, a...)				\
306 	sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
307 
308 __printf(3, 4) void
309 scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
310 
311 #define scmd_dbg(scmd, fmt, a...)					\
312 	do {								\
313 		struct request *__rq = scsi_cmd_to_rq((scmd));		\
314 									\
315 		if (__rq->q->disk)					\
316 			sdev_dbg((scmd)->device, "[%s] " fmt,		\
317 				 __rq->q->disk->disk_name, ##a);	\
318 		else							\
319 			sdev_dbg((scmd)->device, fmt, ##a);		\
320 	} while (0)
321 
322 enum scsi_target_state {
323 	STARGET_CREATED = 1,
324 	STARGET_RUNNING,
325 	STARGET_REMOVE,
326 	STARGET_CREATED_REMOVE,
327 	STARGET_DEL,
328 };
329 
330 /*
331  * scsi_target: representation of a scsi target, for now, this is only
332  * used for single_lun devices. If no one has active IO to the target,
333  * starget_sdev_user is NULL, else it points to the active sdev.
334  */
335 struct scsi_target {
336 	struct scsi_device	*starget_sdev_user;
337 	struct list_head	siblings;
338 	struct list_head	devices;
339 	struct device		dev;
340 	struct kref		reap_ref; /* last put renders target invisible */
341 	unsigned int		channel;
342 	unsigned int		id; /* target id ... replace
343 				     * scsi_device.id eventually */
344 	unsigned int		create:1; /* signal that it needs to be added */
345 	unsigned int		single_lun:1;	/* Indicates we should only
346 						 * allow I/O to one of the luns
347 						 * for the device at a time. */
348 	unsigned int		pdt_1f_for_no_lun:1;	/* PDT = 0x1f
349 						 * means no lun present. */
350 	unsigned int		no_report_luns:1;	/* Don't use
351 						 * REPORT LUNS for scanning. */
352 	unsigned int		expecting_lun_change:1;	/* A device has reported
353 						 * a 3F/0E UA, other devices on
354 						 * the same target will also. */
355 	/* commands actually active on LLD. */
356 	atomic_t		target_busy;
357 	atomic_t		target_blocked;
358 
359 	/*
360 	 * LLDs should set this in the slave_alloc host template callout.
361 	 * If set to zero then there is not limit.
362 	 */
363 	unsigned int		can_queue;
364 	unsigned int		max_target_blocked;
365 #define SCSI_DEFAULT_TARGET_BLOCKED	3
366 
367 	char			scsi_level;
368 	enum scsi_target_state	state;
369 	void 			*hostdata; /* available to low-level driver */
370 	unsigned long		starget_data[]; /* for the transport */
371 	/* starget_data must be the last element!!!! */
372 } __attribute__((aligned(sizeof(unsigned long))));
373 
374 #define to_scsi_target(d)	container_of(d, struct scsi_target, dev)
375 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
376 {
377 	return to_scsi_target(sdev->sdev_gendev.parent);
378 }
379 #define transport_class_to_starget(class_dev) \
380 	to_scsi_target(class_dev->parent)
381 
382 #define starget_printk(prefix, starget, fmt, a...)	\
383 	dev_printk(prefix, &(starget)->dev, fmt, ##a)
384 
385 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
386 		uint, uint, u64, void *hostdata);
387 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
388 			   uint target, u64 lun);
389 extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
390 extern void scsi_remove_device(struct scsi_device *);
391 extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
392 void scsi_attach_vpd(struct scsi_device *sdev);
393 void scsi_cdl_check(struct scsi_device *sdev);
394 int scsi_cdl_enable(struct scsi_device *sdev, bool enable);
395 
396 extern struct scsi_device *scsi_device_from_queue(struct request_queue *q);
397 extern int __must_check scsi_device_get(struct scsi_device *);
398 extern void scsi_device_put(struct scsi_device *);
399 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
400 					      uint, uint, u64);
401 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
402 						uint, uint, u64);
403 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
404 							u64);
405 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
406 							  u64);
407 extern void starget_for_each_device(struct scsi_target *, void *,
408 		     void (*fn)(struct scsi_device *, void *));
409 extern void __starget_for_each_device(struct scsi_target *, void *,
410 				      void (*fn)(struct scsi_device *,
411 						 void *));
412 
413 /* only exposed to implement shost_for_each_device */
414 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
415 						  struct scsi_device *);
416 
417 /**
418  * shost_for_each_device - iterate over all devices of a host
419  * @sdev: the &struct scsi_device to use as a cursor
420  * @shost: the &struct scsi_host to iterate over
421  *
422  * Iterator that returns each device attached to @shost.  This loop
423  * takes a reference on each device and releases it at the end.  If
424  * you break out of the loop, you must call scsi_device_put(sdev).
425  */
426 #define shost_for_each_device(sdev, shost) \
427 	for ((sdev) = __scsi_iterate_devices((shost), NULL); \
428 	     (sdev); \
429 	     (sdev) = __scsi_iterate_devices((shost), (sdev)))
430 
431 /**
432  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
433  * @sdev: the &struct scsi_device to use as a cursor
434  * @shost: the &struct scsi_host to iterate over
435  *
436  * Iterator that returns each device attached to @shost.  It does _not_
437  * take a reference on the scsi_device, so the whole loop must be
438  * protected by shost->host_lock.
439  *
440  * Note: The only reason to use this is because you need to access the
441  * device list in interrupt context.  Otherwise you really want to use
442  * shost_for_each_device instead.
443  */
444 #define __shost_for_each_device(sdev, shost) \
445 	list_for_each_entry((sdev), &((shost)->__devices), siblings)
446 
447 extern int scsi_change_queue_depth(struct scsi_device *, int);
448 extern int scsi_track_queue_full(struct scsi_device *, int);
449 
450 extern int scsi_set_medium_removal(struct scsi_device *, char);
451 
452 int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
453 		    int subpage, unsigned char *buffer, int len, int timeout,
454 		    int retries, struct scsi_mode_data *data,
455 		    struct scsi_sense_hdr *);
456 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
457 			    unsigned char *buffer, int len, int timeout,
458 			    int retries, struct scsi_mode_data *data,
459 			    struct scsi_sense_hdr *);
460 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
461 				int retries, struct scsi_sense_hdr *sshdr);
462 extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
463 			     int buf_len);
464 int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
465 		       unsigned int len, unsigned char opcode,
466 		       unsigned short sa);
467 extern int scsi_device_set_state(struct scsi_device *sdev,
468 				 enum scsi_device_state state);
469 extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
470 					  gfp_t gfpflags);
471 extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
472 extern void sdev_evt_send_simple(struct scsi_device *sdev,
473 			  enum scsi_device_event evt_type, gfp_t gfpflags);
474 extern int scsi_device_quiesce(struct scsi_device *sdev);
475 extern void scsi_device_resume(struct scsi_device *sdev);
476 extern void scsi_target_quiesce(struct scsi_target *);
477 extern void scsi_target_resume(struct scsi_target *);
478 extern void scsi_scan_target(struct device *parent, unsigned int channel,
479 			     unsigned int id, u64 lun,
480 			     enum scsi_scan_mode rescan);
481 extern void scsi_target_reap(struct scsi_target *);
482 void scsi_block_targets(struct Scsi_Host *shost, struct device *dev);
483 extern void scsi_target_unblock(struct device *, enum scsi_device_state);
484 extern void scsi_remove_target(struct device *);
485 extern const char *scsi_device_state_name(enum scsi_device_state);
486 extern int scsi_is_sdev_device(const struct device *);
487 extern int scsi_is_target_device(const struct device *);
488 extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
489 
490 /*
491  * scsi_execute_cmd users can set scsi_failure.result to have
492  * scsi_check_passthrough fail/retry a command. scsi_failure.result can be a
493  * specific host byte or message code, or SCMD_FAILURE_RESULT_ANY can be used
494  * to match any host or message code.
495  */
496 #define SCMD_FAILURE_RESULT_ANY	0x7fffffff
497 /*
498  * Set scsi_failure.result to SCMD_FAILURE_STAT_ANY to fail/retry any failure
499  * scsi_status_is_good returns false for.
500  */
501 #define SCMD_FAILURE_STAT_ANY	0xff
502 /*
503  * The following can be set to the scsi_failure sense, asc and ascq fields to
504  * match on any sense, ASC, or ASCQ value.
505  */
506 #define SCMD_FAILURE_SENSE_ANY	0xff
507 #define SCMD_FAILURE_ASC_ANY	0xff
508 #define SCMD_FAILURE_ASCQ_ANY	0xff
509 /* Always retry a matching failure. */
510 #define SCMD_FAILURE_NO_LIMIT	-1
511 
512 struct scsi_failure {
513 	int result;
514 	u8 sense;
515 	u8 asc;
516 	u8 ascq;
517 	/*
518 	 * Number of times scsi_execute_cmd will retry the failure. It does
519 	 * not count for the total_allowed.
520 	 */
521 	s8 allowed;
522 	/* Number of times the failure has been retried. */
523 	s8 retries;
524 };
525 
526 struct scsi_failures {
527 	/*
528 	 * If a scsi_failure does not have a retry limit setup this limit will
529 	 * be used.
530 	 */
531 	int total_allowed;
532 	int total_retries;
533 	struct scsi_failure *failure_definitions;
534 };
535 
536 /* Optional arguments to scsi_execute_cmd */
537 struct scsi_exec_args {
538 	unsigned char *sense;		/* sense buffer */
539 	unsigned int sense_len;		/* sense buffer len */
540 	struct scsi_sense_hdr *sshdr;	/* decoded sense header */
541 	blk_mq_req_flags_t req_flags;	/* BLK_MQ_REQ flags */
542 	int scmd_flags;			/* SCMD flags */
543 	int *resid;			/* residual length */
544 	struct scsi_failures *failures;	/* failures to retry */
545 };
546 
547 int scsi_execute_cmd(struct scsi_device *sdev, const unsigned char *cmd,
548 		     blk_opf_t opf, void *buffer, unsigned int bufflen,
549 		     int timeout, int retries,
550 		     const struct scsi_exec_args *args);
551 void scsi_failures_reset_retries(struct scsi_failures *failures);
552 
553 extern void sdev_disable_disk_events(struct scsi_device *sdev);
554 extern void sdev_enable_disk_events(struct scsi_device *sdev);
555 extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
556 extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
557 
558 #ifdef CONFIG_PM
559 extern int scsi_autopm_get_device(struct scsi_device *);
560 extern void scsi_autopm_put_device(struct scsi_device *);
561 #else
562 static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
563 static inline void scsi_autopm_put_device(struct scsi_device *d) {}
564 #endif /* CONFIG_PM */
565 
566 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
567 {
568 	return device_reprobe(&sdev->sdev_gendev);
569 }
570 
571 static inline unsigned int sdev_channel(struct scsi_device *sdev)
572 {
573 	return sdev->channel;
574 }
575 
576 static inline unsigned int sdev_id(struct scsi_device *sdev)
577 {
578 	return sdev->id;
579 }
580 
581 #define scmd_id(scmd) sdev_id((scmd)->device)
582 #define scmd_channel(scmd) sdev_channel((scmd)->device)
583 
584 /*
585  * checks for positions of the SCSI state machine
586  */
587 static inline int scsi_device_online(struct scsi_device *sdev)
588 {
589 	return (sdev->sdev_state != SDEV_OFFLINE &&
590 		sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
591 		sdev->sdev_state != SDEV_DEL);
592 }
593 static inline int scsi_device_blocked(struct scsi_device *sdev)
594 {
595 	return sdev->sdev_state == SDEV_BLOCK ||
596 		sdev->sdev_state == SDEV_CREATED_BLOCK;
597 }
598 static inline int scsi_device_created(struct scsi_device *sdev)
599 {
600 	return sdev->sdev_state == SDEV_CREATED ||
601 		sdev->sdev_state == SDEV_CREATED_BLOCK;
602 }
603 
604 int scsi_internal_device_block_nowait(struct scsi_device *sdev);
605 int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
606 					enum scsi_device_state new_state);
607 
608 /* accessor functions for the SCSI parameters */
609 static inline int scsi_device_sync(struct scsi_device *sdev)
610 {
611 	return sdev->sdtr;
612 }
613 static inline int scsi_device_wide(struct scsi_device *sdev)
614 {
615 	return sdev->wdtr;
616 }
617 static inline int scsi_device_dt(struct scsi_device *sdev)
618 {
619 	return sdev->ppr;
620 }
621 static inline int scsi_device_dt_only(struct scsi_device *sdev)
622 {
623 	if (sdev->inquiry_len < 57)
624 		return 0;
625 	return (sdev->inquiry[56] & 0x0c) == 0x04;
626 }
627 static inline int scsi_device_ius(struct scsi_device *sdev)
628 {
629 	if (sdev->inquiry_len < 57)
630 		return 0;
631 	return sdev->inquiry[56] & 0x01;
632 }
633 static inline int scsi_device_qas(struct scsi_device *sdev)
634 {
635 	if (sdev->inquiry_len < 57)
636 		return 0;
637 	return sdev->inquiry[56] & 0x02;
638 }
639 static inline int scsi_device_enclosure(struct scsi_device *sdev)
640 {
641 	return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
642 }
643 
644 static inline int scsi_device_protection(struct scsi_device *sdev)
645 {
646 	if (sdev->no_dif)
647 		return 0;
648 
649 	return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
650 }
651 
652 static inline int scsi_device_tpgs(struct scsi_device *sdev)
653 {
654 	return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
655 }
656 
657 /**
658  * scsi_device_supports_vpd - test if a device supports VPD pages
659  * @sdev: the &struct scsi_device to test
660  *
661  * If the 'try_vpd_pages' flag is set it takes precedence.
662  * Otherwise we will assume VPD pages are supported if the
663  * SCSI level is at least SPC-3 and 'skip_vpd_pages' is not set.
664  */
665 static inline int scsi_device_supports_vpd(struct scsi_device *sdev)
666 {
667 	/* Attempt VPD inquiry if the device blacklist explicitly calls
668 	 * for it.
669 	 */
670 	if (sdev->try_vpd_pages)
671 		return 1;
672 	/*
673 	 * Although VPD inquiries can go to SCSI-2 type devices,
674 	 * some USB ones crash on receiving them, and the pages
675 	 * we currently ask for are mandatory for SPC-2 and beyond
676 	 */
677 	if (sdev->scsi_level >= SCSI_SPC_2 && !sdev->skip_vpd_pages)
678 		return 1;
679 	return 0;
680 }
681 
682 static inline int scsi_device_busy(struct scsi_device *sdev)
683 {
684 	return sbitmap_weight(&sdev->budget_map);
685 }
686 
687 #define MODULE_ALIAS_SCSI_DEVICE(type) \
688 	MODULE_ALIAS("scsi:t-" __stringify(type) "*")
689 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
690 
691 #endif /* _SCSI_SCSI_DEVICE_H */
692