xref: /linux/include/scsi/scsi_device.h (revision b2d0f5d5dc53532e6f07bc546a476a55ebdfe0f3)
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/blkdev.h>
9 #include <scsi/scsi.h>
10 #include <linux/atomic.h>
11 
12 struct device;
13 struct request_queue;
14 struct scsi_cmnd;
15 struct scsi_lun;
16 struct scsi_sense_hdr;
17 
18 struct scsi_mode_data {
19 	__u32	length;
20 	__u16	block_descriptor_length;
21 	__u8	medium_type;
22 	__u8	device_specific;
23 	__u8	header_length;
24 	__u8	longlba:1;
25 };
26 
27 /*
28  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
29  * (for the ascii descriptions) and the state model enforcer:
30  * scsi_lib:scsi_device_set_state().
31  */
32 enum scsi_device_state {
33 	SDEV_CREATED = 1,	/* device created but not added to sysfs
34 				 * Only internal commands allowed (for inq) */
35 	SDEV_RUNNING,		/* device properly configured
36 				 * All commands allowed */
37 	SDEV_CANCEL,		/* beginning to delete device
38 				 * Only error handler commands allowed */
39 	SDEV_DEL,		/* device deleted
40 				 * no commands allowed */
41 	SDEV_QUIESCE,		/* Device quiescent.  No block commands
42 				 * will be accepted, only specials (which
43 				 * originate in the mid-layer) */
44 	SDEV_OFFLINE,		/* Device offlined (by error handling or
45 				 * user request */
46 	SDEV_TRANSPORT_OFFLINE,	/* Offlined by transport class error handler */
47 	SDEV_BLOCK,		/* Device blocked by scsi lld.  No
48 				 * scsi commands from user or midlayer
49 				 * should be issued to the scsi
50 				 * lld. */
51 	SDEV_CREATED_BLOCK,	/* same as above but for created devices */
52 };
53 
54 enum scsi_scan_mode {
55 	SCSI_SCAN_INITIAL = 0,
56 	SCSI_SCAN_RESCAN,
57 	SCSI_SCAN_MANUAL,
58 };
59 
60 enum scsi_device_event {
61 	SDEV_EVT_MEDIA_CHANGE	= 1,	/* media has changed */
62 	SDEV_EVT_INQUIRY_CHANGE_REPORTED,		/* 3F 03  UA reported */
63 	SDEV_EVT_CAPACITY_CHANGE_REPORTED,		/* 2A 09  UA reported */
64 	SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,	/* 38 07  UA reported */
65 	SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,	/* 2A 01  UA reported */
66 	SDEV_EVT_LUN_CHANGE_REPORTED,			/* 3F 0E  UA reported */
67 	SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,		/* 2A 06  UA reported */
68 
69 	SDEV_EVT_FIRST		= SDEV_EVT_MEDIA_CHANGE,
70 	SDEV_EVT_LAST		= SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,
71 
72 	SDEV_EVT_MAXBITS	= SDEV_EVT_LAST + 1
73 };
74 
75 struct scsi_event {
76 	enum scsi_device_event	evt_type;
77 	struct list_head	node;
78 
79 	/* put union of data structures, for non-simple event types,
80 	 * here
81 	 */
82 };
83 
84 /**
85  * struct scsi_vpd - SCSI Vital Product Data
86  * @rcu: For kfree_rcu().
87  * @len: Length in bytes of @data.
88  * @data: VPD data as defined in various T10 SCSI standard documents.
89  */
90 struct scsi_vpd {
91 	struct rcu_head	rcu;
92 	int		len;
93 	unsigned char	data[];
94 };
95 
96 struct scsi_device {
97 	struct Scsi_Host *host;
98 	struct request_queue *request_queue;
99 
100 	/* the next two are protected by the host->host_lock */
101 	struct list_head    siblings;   /* list of all devices on this host */
102 	struct list_head    same_target_siblings; /* just the devices sharing same target id */
103 
104 	atomic_t device_busy;		/* commands actually active on LLDD */
105 	atomic_t device_blocked;	/* Device returned QUEUE_FULL. */
106 
107 	spinlock_t list_lock;
108 	struct list_head cmd_list;	/* queue of in use SCSI Command structures */
109 	struct list_head starved_entry;
110 	unsigned short queue_depth;	/* How deep of a queue we want */
111 	unsigned short max_queue_depth;	/* max queue depth */
112 	unsigned short last_queue_full_depth; /* These two are used by */
113 	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
114 	unsigned long last_queue_full_time;	/* last queue full time */
115 	unsigned long queue_ramp_up_period;	/* ramp up period in jiffies */
116 #define SCSI_DEFAULT_RAMP_UP_PERIOD	(120 * HZ)
117 
118 	unsigned long last_queue_ramp_up;	/* last queue ramp up time */
119 
120 	unsigned int id, channel;
121 	u64 lun;
122 	unsigned int manufacturer;	/* Manufacturer of device, for using
123 					 * vendor-specific cmd's */
124 	unsigned sector_size;	/* size in bytes */
125 
126 	void *hostdata;		/* available to low-level driver */
127 	unsigned char type;
128 	char scsi_level;
129 	char inq_periph_qual;	/* PQ from INQUIRY data */
130 	struct mutex inquiry_mutex;
131 	unsigned char inquiry_len;	/* valid bytes in 'inquiry' */
132 	unsigned char * inquiry;	/* INQUIRY response data */
133 	const char * vendor;		/* [back_compat] point into 'inquiry' ... */
134 	const char * model;		/* ... after scan; point to static string */
135 	const char * rev;		/* ... "nullnullnullnull" before scan */
136 
137 #define SCSI_VPD_PG_LEN                255
138 	struct scsi_vpd __rcu *vpd_pg83;
139 	struct scsi_vpd __rcu *vpd_pg80;
140 	unsigned char current_tag;	/* current tag */
141 	struct scsi_target      *sdev_target;   /* used only for single_lun */
142 
143 	unsigned int	sdev_bflags; /* black/white flags as also found in
144 				 * scsi_devinfo.[hc]. For now used only to
145 				 * pass settings from slave_alloc to scsi
146 				 * core. */
147 	unsigned int eh_timeout; /* Error handling timeout */
148 	unsigned removable:1;
149 	unsigned changed:1;	/* Data invalid due to media change */
150 	unsigned busy:1;	/* Used to prevent races */
151 	unsigned lockable:1;	/* Able to prevent media removal */
152 	unsigned locked:1;      /* Media removal disabled */
153 	unsigned borken:1;	/* Tell the Seagate driver to be
154 				 * painfully slow on this device */
155 	unsigned disconnect:1;	/* can disconnect */
156 	unsigned soft_reset:1;	/* Uses soft reset option */
157 	unsigned sdtr:1;	/* Device supports SDTR messages */
158 	unsigned wdtr:1;	/* Device supports WDTR messages */
159 	unsigned ppr:1;		/* Device supports PPR messages */
160 	unsigned tagged_supported:1;	/* Supports SCSI-II tagged queuing */
161 	unsigned simple_tags:1;	/* simple queue tag messages are enabled */
162 	unsigned was_reset:1;	/* There was a bus reset on the bus for
163 				 * this device */
164 	unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
165 				     * because we did a bus reset. */
166 	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
167 	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
168 	unsigned no_report_opcodes:1;	/* no REPORT SUPPORTED OPERATION CODES */
169 	unsigned no_write_same:1;	/* no WRITE SAME command */
170 	unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
171 	unsigned skip_ms_page_8:1;	/* do not use MODE SENSE page 0x08 */
172 	unsigned skip_ms_page_3f:1;	/* do not use MODE SENSE page 0x3f */
173 	unsigned skip_vpd_pages:1;	/* do not read VPD pages */
174 	unsigned try_vpd_pages:1;	/* attempt to read VPD pages */
175 	unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
176 	unsigned no_start_on_add:1;	/* do not issue start on add */
177 	unsigned allow_restart:1; /* issue START_UNIT in error handler */
178 	unsigned manage_start_stop:1;	/* Let HLD (sd) manage start/stop */
179 	unsigned start_stop_pwr_cond:1;	/* Set power cond. in START_STOP_UNIT */
180 	unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
181 	unsigned select_no_atn:1;
182 	unsigned fix_capacity:1;	/* READ_CAPACITY is too high by 1 */
183 	unsigned guess_capacity:1;	/* READ_CAPACITY might be too high by 1 */
184 	unsigned retry_hwerror:1;	/* Retry HARDWARE_ERROR */
185 	unsigned last_sector_bug:1;	/* do not use multisector accesses on
186 					   SD_LAST_BUGGY_SECTORS */
187 	unsigned no_read_disc_info:1;	/* Avoid READ_DISC_INFO cmds */
188 	unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
189 	unsigned try_rc_10_first:1;	/* Try READ_CAPACACITY_10 first */
190 	unsigned security_supported:1;	/* Supports Security Protocols */
191 	unsigned is_visible:1;	/* is the device visible in sysfs */
192 	unsigned wce_default_on:1;	/* Cache is ON by default */
193 	unsigned no_dif:1;	/* T10 PI (DIF) should be disabled */
194 	unsigned broken_fua:1;		/* Don't set FUA bit */
195 	unsigned lun_in_cdb:1;		/* Store LUN bits in CDB[1] */
196 	unsigned unmap_limit_for_ws:1;	/* Use the UNMAP limit for WRITE SAME */
197 
198 	atomic_t disk_events_disable_depth; /* disable depth for disk events */
199 
200 	DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
201 	DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
202 	struct list_head event_list;	/* asserted events */
203 	struct work_struct event_work;
204 
205 	unsigned int max_device_blocked; /* what device_blocked counts down from  */
206 #define SCSI_DEFAULT_DEVICE_BLOCKED	3
207 
208 	atomic_t iorequest_cnt;
209 	atomic_t iodone_cnt;
210 	atomic_t ioerr_cnt;
211 
212 	struct device		sdev_gendev,
213 				sdev_dev;
214 
215 	struct execute_work	ew; /* used to get process context on put */
216 	struct work_struct	requeue_work;
217 
218 	struct scsi_device_handler *handler;
219 	void			*handler_data;
220 
221 	unsigned char		access_state;
222 	struct mutex		state_mutex;
223 	enum scsi_device_state sdev_state;
224 	unsigned long		sdev_data[0];
225 } __attribute__((aligned(sizeof(unsigned long))));
226 
227 #define	to_scsi_device(d)	\
228 	container_of(d, struct scsi_device, sdev_gendev)
229 #define	class_to_sdev(d)	\
230 	container_of(d, struct scsi_device, sdev_dev)
231 #define transport_class_to_sdev(class_dev) \
232 	to_scsi_device(class_dev->parent)
233 
234 #define sdev_dbg(sdev, fmt, a...) \
235 	dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)
236 
237 /*
238  * like scmd_printk, but the device name is passed in
239  * as a string pointer
240  */
241 __printf(4, 5) void
242 sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
243 		const char *, ...);
244 
245 #define sdev_printk(l, sdev, fmt, a...)				\
246 	sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
247 
248 __printf(3, 4) void
249 scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
250 
251 #define scmd_dbg(scmd, fmt, a...)					   \
252 	do {								   \
253 		if ((scmd)->request->rq_disk)				   \
254 			sdev_dbg((scmd)->device, "[%s] " fmt,		   \
255 				 (scmd)->request->rq_disk->disk_name, ##a);\
256 		else							   \
257 			sdev_dbg((scmd)->device, fmt, ##a);		   \
258 	} while (0)
259 
260 enum scsi_target_state {
261 	STARGET_CREATED = 1,
262 	STARGET_RUNNING,
263 	STARGET_REMOVE,
264 	STARGET_CREATED_REMOVE,
265 	STARGET_DEL,
266 };
267 
268 /*
269  * scsi_target: representation of a scsi target, for now, this is only
270  * used for single_lun devices. If no one has active IO to the target,
271  * starget_sdev_user is NULL, else it points to the active sdev.
272  */
273 struct scsi_target {
274 	struct scsi_device	*starget_sdev_user;
275 	struct list_head	siblings;
276 	struct list_head	devices;
277 	struct device		dev;
278 	struct kref		reap_ref; /* last put renders target invisible */
279 	unsigned int		channel;
280 	unsigned int		id; /* target id ... replace
281 				     * scsi_device.id eventually */
282 	unsigned int		create:1; /* signal that it needs to be added */
283 	unsigned int		single_lun:1;	/* Indicates we should only
284 						 * allow I/O to one of the luns
285 						 * for the device at a time. */
286 	unsigned int		pdt_1f_for_no_lun:1;	/* PDT = 0x1f
287 						 * means no lun present. */
288 	unsigned int		no_report_luns:1;	/* Don't use
289 						 * REPORT LUNS for scanning. */
290 	unsigned int		expecting_lun_change:1;	/* A device has reported
291 						 * a 3F/0E UA, other devices on
292 						 * the same target will also. */
293 	/* commands actually active on LLD. */
294 	atomic_t		target_busy;
295 	atomic_t		target_blocked;
296 
297 	/*
298 	 * LLDs should set this in the slave_alloc host template callout.
299 	 * If set to zero then there is not limit.
300 	 */
301 	unsigned int		can_queue;
302 	unsigned int		max_target_blocked;
303 #define SCSI_DEFAULT_TARGET_BLOCKED	3
304 
305 	char			scsi_level;
306 	enum scsi_target_state	state;
307 	void 			*hostdata; /* available to low-level driver */
308 	unsigned long		starget_data[0]; /* for the transport */
309 	/* starget_data must be the last element!!!! */
310 } __attribute__((aligned(sizeof(unsigned long))));
311 
312 #define to_scsi_target(d)	container_of(d, struct scsi_target, dev)
313 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
314 {
315 	return to_scsi_target(sdev->sdev_gendev.parent);
316 }
317 #define transport_class_to_starget(class_dev) \
318 	to_scsi_target(class_dev->parent)
319 
320 #define starget_printk(prefix, starget, fmt, a...)	\
321 	dev_printk(prefix, &(starget)->dev, fmt, ##a)
322 
323 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
324 		uint, uint, u64, void *hostdata);
325 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
326 			   uint target, u64 lun);
327 extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
328 extern void scsi_remove_device(struct scsi_device *);
329 extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
330 void scsi_attach_vpd(struct scsi_device *sdev);
331 
332 extern struct scsi_device *scsi_device_from_queue(struct request_queue *q);
333 extern int __must_check scsi_device_get(struct scsi_device *);
334 extern void scsi_device_put(struct scsi_device *);
335 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
336 					      uint, uint, u64);
337 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
338 						uint, uint, u64);
339 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
340 							u64);
341 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
342 							  u64);
343 extern void starget_for_each_device(struct scsi_target *, void *,
344 		     void (*fn)(struct scsi_device *, void *));
345 extern void __starget_for_each_device(struct scsi_target *, void *,
346 				      void (*fn)(struct scsi_device *,
347 						 void *));
348 
349 /* only exposed to implement shost_for_each_device */
350 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
351 						  struct scsi_device *);
352 
353 /**
354  * shost_for_each_device - iterate over all devices of a host
355  * @sdev: the &struct scsi_device to use as a cursor
356  * @shost: the &struct scsi_host to iterate over
357  *
358  * Iterator that returns each device attached to @shost.  This loop
359  * takes a reference on each device and releases it at the end.  If
360  * you break out of the loop, you must call scsi_device_put(sdev).
361  */
362 #define shost_for_each_device(sdev, shost) \
363 	for ((sdev) = __scsi_iterate_devices((shost), NULL); \
364 	     (sdev); \
365 	     (sdev) = __scsi_iterate_devices((shost), (sdev)))
366 
367 /**
368  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
369  * @sdev: the &struct scsi_device to use as a cursor
370  * @shost: the &struct scsi_host to iterate over
371  *
372  * Iterator that returns each device attached to @shost.  It does _not_
373  * take a reference on the scsi_device, so the whole loop must be
374  * protected by shost->host_lock.
375  *
376  * Note: The only reason to use this is because you need to access the
377  * device list in interrupt context.  Otherwise you really want to use
378  * shost_for_each_device instead.
379  */
380 #define __shost_for_each_device(sdev, shost) \
381 	list_for_each_entry((sdev), &((shost)->__devices), siblings)
382 
383 extern int scsi_change_queue_depth(struct scsi_device *, int);
384 extern int scsi_track_queue_full(struct scsi_device *, int);
385 
386 extern int scsi_set_medium_removal(struct scsi_device *, char);
387 
388 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
389 			   unsigned char *buffer, int len, int timeout,
390 			   int retries, struct scsi_mode_data *data,
391 			   struct scsi_sense_hdr *);
392 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
393 			    int modepage, unsigned char *buffer, int len,
394 			    int timeout, int retries,
395 			    struct scsi_mode_data *data,
396 			    struct scsi_sense_hdr *);
397 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
398 				int retries, struct scsi_sense_hdr *sshdr);
399 extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
400 			     int buf_len);
401 extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
402 			      unsigned int len, unsigned char opcode);
403 extern int scsi_device_set_state(struct scsi_device *sdev,
404 				 enum scsi_device_state state);
405 extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
406 					  gfp_t gfpflags);
407 extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
408 extern void sdev_evt_send_simple(struct scsi_device *sdev,
409 			  enum scsi_device_event evt_type, gfp_t gfpflags);
410 extern int scsi_device_quiesce(struct scsi_device *sdev);
411 extern void scsi_device_resume(struct scsi_device *sdev);
412 extern void scsi_target_quiesce(struct scsi_target *);
413 extern void scsi_target_resume(struct scsi_target *);
414 extern void scsi_scan_target(struct device *parent, unsigned int channel,
415 			     unsigned int id, u64 lun,
416 			     enum scsi_scan_mode rescan);
417 extern void scsi_target_reap(struct scsi_target *);
418 extern void scsi_target_block(struct device *);
419 extern void scsi_target_unblock(struct device *, enum scsi_device_state);
420 extern void scsi_remove_target(struct device *);
421 extern const char *scsi_device_state_name(enum scsi_device_state);
422 extern int scsi_is_sdev_device(const struct device *);
423 extern int scsi_is_target_device(const struct device *);
424 extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
425 extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
426 			int data_direction, void *buffer, unsigned bufflen,
427 			unsigned char *sense, struct scsi_sense_hdr *sshdr,
428 			int timeout, int retries, u64 flags,
429 			req_flags_t rq_flags, int *resid);
430 static inline int scsi_execute_req(struct scsi_device *sdev,
431 	const unsigned char *cmd, int data_direction, void *buffer,
432 	unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
433 	int retries, int *resid)
434 {
435 	return scsi_execute(sdev, cmd, data_direction, buffer,
436 		bufflen, NULL, sshdr, timeout, retries,  0, 0, resid);
437 }
438 extern void sdev_disable_disk_events(struct scsi_device *sdev);
439 extern void sdev_enable_disk_events(struct scsi_device *sdev);
440 extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
441 extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
442 
443 #ifdef CONFIG_PM
444 extern int scsi_autopm_get_device(struct scsi_device *);
445 extern void scsi_autopm_put_device(struct scsi_device *);
446 #else
447 static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
448 static inline void scsi_autopm_put_device(struct scsi_device *d) {}
449 #endif /* CONFIG_PM */
450 
451 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
452 {
453 	return device_reprobe(&sdev->sdev_gendev);
454 }
455 
456 static inline unsigned int sdev_channel(struct scsi_device *sdev)
457 {
458 	return sdev->channel;
459 }
460 
461 static inline unsigned int sdev_id(struct scsi_device *sdev)
462 {
463 	return sdev->id;
464 }
465 
466 #define scmd_id(scmd) sdev_id((scmd)->device)
467 #define scmd_channel(scmd) sdev_channel((scmd)->device)
468 
469 /*
470  * checks for positions of the SCSI state machine
471  */
472 static inline int scsi_device_online(struct scsi_device *sdev)
473 {
474 	return (sdev->sdev_state != SDEV_OFFLINE &&
475 		sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
476 		sdev->sdev_state != SDEV_DEL);
477 }
478 static inline int scsi_device_blocked(struct scsi_device *sdev)
479 {
480 	return sdev->sdev_state == SDEV_BLOCK ||
481 		sdev->sdev_state == SDEV_CREATED_BLOCK;
482 }
483 static inline int scsi_device_created(struct scsi_device *sdev)
484 {
485 	return sdev->sdev_state == SDEV_CREATED ||
486 		sdev->sdev_state == SDEV_CREATED_BLOCK;
487 }
488 
489 int scsi_internal_device_block_nowait(struct scsi_device *sdev);
490 int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
491 					enum scsi_device_state new_state);
492 
493 /* accessor functions for the SCSI parameters */
494 static inline int scsi_device_sync(struct scsi_device *sdev)
495 {
496 	return sdev->sdtr;
497 }
498 static inline int scsi_device_wide(struct scsi_device *sdev)
499 {
500 	return sdev->wdtr;
501 }
502 static inline int scsi_device_dt(struct scsi_device *sdev)
503 {
504 	return sdev->ppr;
505 }
506 static inline int scsi_device_dt_only(struct scsi_device *sdev)
507 {
508 	if (sdev->inquiry_len < 57)
509 		return 0;
510 	return (sdev->inquiry[56] & 0x0c) == 0x04;
511 }
512 static inline int scsi_device_ius(struct scsi_device *sdev)
513 {
514 	if (sdev->inquiry_len < 57)
515 		return 0;
516 	return sdev->inquiry[56] & 0x01;
517 }
518 static inline int scsi_device_qas(struct scsi_device *sdev)
519 {
520 	if (sdev->inquiry_len < 57)
521 		return 0;
522 	return sdev->inquiry[56] & 0x02;
523 }
524 static inline int scsi_device_enclosure(struct scsi_device *sdev)
525 {
526 	return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
527 }
528 
529 static inline int scsi_device_protection(struct scsi_device *sdev)
530 {
531 	if (sdev->no_dif)
532 		return 0;
533 
534 	return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
535 }
536 
537 static inline int scsi_device_tpgs(struct scsi_device *sdev)
538 {
539 	return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
540 }
541 
542 /**
543  * scsi_device_supports_vpd - test if a device supports VPD pages
544  * @sdev: the &struct scsi_device to test
545  *
546  * If the 'try_vpd_pages' flag is set it takes precedence.
547  * Otherwise we will assume VPD pages are supported if the
548  * SCSI level is at least SPC-3 and 'skip_vpd_pages' is not set.
549  */
550 static inline int scsi_device_supports_vpd(struct scsi_device *sdev)
551 {
552 	/* Attempt VPD inquiry if the device blacklist explicitly calls
553 	 * for it.
554 	 */
555 	if (sdev->try_vpd_pages)
556 		return 1;
557 	/*
558 	 * Although VPD inquiries can go to SCSI-2 type devices,
559 	 * some USB ones crash on receiving them, and the pages
560 	 * we currently ask for are mandatory for SPC-2 and beyond
561 	 */
562 	if (sdev->scsi_level >= SCSI_SPC_2 && !sdev->skip_vpd_pages)
563 		return 1;
564 	return 0;
565 }
566 
567 #define MODULE_ALIAS_SCSI_DEVICE(type) \
568 	MODULE_ALIAS("scsi:t-" __stringify(type) "*")
569 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
570 
571 #endif /* _SCSI_SCSI_DEVICE_H */
572