xref: /openbmc/linux/include/scsi/scsi_device.h (revision 8bd1369b)
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 typedef __u64 __bitwise blist_flags_t;
19 
20 struct scsi_mode_data {
21 	__u32	length;
22 	__u16	block_descriptor_length;
23 	__u8	medium_type;
24 	__u8	device_specific;
25 	__u8	header_length;
26 	__u8	longlba:1;
27 };
28 
29 /*
30  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
31  * (for the ascii descriptions) and the state model enforcer:
32  * scsi_lib:scsi_device_set_state().
33  */
34 enum scsi_device_state {
35 	SDEV_CREATED = 1,	/* device created but not added to sysfs
36 				 * Only internal commands allowed (for inq) */
37 	SDEV_RUNNING,		/* device properly configured
38 				 * All commands allowed */
39 	SDEV_CANCEL,		/* beginning to delete device
40 				 * Only error handler commands allowed */
41 	SDEV_DEL,		/* device deleted
42 				 * no commands allowed */
43 	SDEV_QUIESCE,		/* Device quiescent.  No block commands
44 				 * will be accepted, only specials (which
45 				 * originate in the mid-layer) */
46 	SDEV_OFFLINE,		/* Device offlined (by error handling or
47 				 * user request */
48 	SDEV_TRANSPORT_OFFLINE,	/* Offlined by transport class error handler */
49 	SDEV_BLOCK,		/* Device blocked by scsi lld.  No
50 				 * scsi commands from user or midlayer
51 				 * should be issued to the scsi
52 				 * lld. */
53 	SDEV_CREATED_BLOCK,	/* same as above but for created devices */
54 };
55 
56 enum scsi_scan_mode {
57 	SCSI_SCAN_INITIAL = 0,
58 	SCSI_SCAN_RESCAN,
59 	SCSI_SCAN_MANUAL,
60 };
61 
62 enum scsi_device_event {
63 	SDEV_EVT_MEDIA_CHANGE	= 1,	/* media has changed */
64 	SDEV_EVT_INQUIRY_CHANGE_REPORTED,		/* 3F 03  UA reported */
65 	SDEV_EVT_CAPACITY_CHANGE_REPORTED,		/* 2A 09  UA reported */
66 	SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,	/* 38 07  UA reported */
67 	SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,	/* 2A 01  UA reported */
68 	SDEV_EVT_LUN_CHANGE_REPORTED,			/* 3F 0E  UA reported */
69 	SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,		/* 2A 06  UA reported */
70 	SDEV_EVT_POWER_ON_RESET_OCCURRED,		/* 29 00  UA reported */
71 
72 	SDEV_EVT_FIRST		= SDEV_EVT_MEDIA_CHANGE,
73 	SDEV_EVT_LAST		= SDEV_EVT_POWER_ON_RESET_OCCURRED,
74 
75 	SDEV_EVT_MAXBITS	= SDEV_EVT_LAST + 1
76 };
77 
78 struct scsi_event {
79 	enum scsi_device_event	evt_type;
80 	struct list_head	node;
81 
82 	/* put union of data structures, for non-simple event types,
83 	 * here
84 	 */
85 };
86 
87 /**
88  * struct scsi_vpd - SCSI Vital Product Data
89  * @rcu: For kfree_rcu().
90  * @len: Length in bytes of @data.
91  * @data: VPD data as defined in various T10 SCSI standard documents.
92  */
93 struct scsi_vpd {
94 	struct rcu_head	rcu;
95 	int		len;
96 	unsigned char	data[];
97 };
98 
99 struct scsi_device {
100 	struct Scsi_Host *host;
101 	struct request_queue *request_queue;
102 
103 	/* the next two are protected by the host->host_lock */
104 	struct list_head    siblings;   /* list of all devices on this host */
105 	struct list_head    same_target_siblings; /* just the devices sharing same target id */
106 
107 	atomic_t device_busy;		/* commands actually active on LLDD */
108 	atomic_t device_blocked;	/* Device returned QUEUE_FULL. */
109 
110 	spinlock_t list_lock;
111 	struct list_head cmd_list;	/* queue of in use SCSI Command structures */
112 	struct list_head starved_entry;
113 	unsigned short queue_depth;	/* How deep of a queue we want */
114 	unsigned short max_queue_depth;	/* max queue depth */
115 	unsigned short last_queue_full_depth; /* These two are used by */
116 	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
117 	unsigned long last_queue_full_time;	/* last queue full time */
118 	unsigned long queue_ramp_up_period;	/* ramp up period in jiffies */
119 #define SCSI_DEFAULT_RAMP_UP_PERIOD	(120 * HZ)
120 
121 	unsigned long last_queue_ramp_up;	/* last queue ramp up time */
122 
123 	unsigned int id, channel;
124 	u64 lun;
125 	unsigned int manufacturer;	/* Manufacturer of device, for using
126 					 * vendor-specific cmd's */
127 	unsigned sector_size;	/* size in bytes */
128 
129 	void *hostdata;		/* available to low-level driver */
130 	unsigned char type;
131 	char scsi_level;
132 	char inq_periph_qual;	/* PQ from INQUIRY data */
133 	struct mutex inquiry_mutex;
134 	unsigned char inquiry_len;	/* valid bytes in 'inquiry' */
135 	unsigned char * inquiry;	/* INQUIRY response data */
136 	const char * vendor;		/* [back_compat] point into 'inquiry' ... */
137 	const char * model;		/* ... after scan; point to static string */
138 	const char * rev;		/* ... "nullnullnullnull" before scan */
139 
140 #define SCSI_VPD_PG_LEN                255
141 	struct scsi_vpd __rcu *vpd_pg83;
142 	struct scsi_vpd __rcu *vpd_pg80;
143 	unsigned char current_tag;	/* current tag */
144 	struct scsi_target      *sdev_target;   /* used only for single_lun */
145 
146 	blist_flags_t		sdev_bflags; /* black/white flags as also found in
147 				 * scsi_devinfo.[hc]. For now used only to
148 				 * pass settings from slave_alloc to scsi
149 				 * core. */
150 	unsigned int eh_timeout; /* Error handling timeout */
151 	unsigned removable:1;
152 	unsigned changed:1;	/* Data invalid due to media change */
153 	unsigned busy:1;	/* Used to prevent races */
154 	unsigned lockable:1;	/* Able to prevent media removal */
155 	unsigned locked:1;      /* Media removal disabled */
156 	unsigned borken:1;	/* Tell the Seagate driver to be
157 				 * painfully slow on this device */
158 	unsigned disconnect:1;	/* can disconnect */
159 	unsigned soft_reset:1;	/* Uses soft reset option */
160 	unsigned sdtr:1;	/* Device supports SDTR messages */
161 	unsigned wdtr:1;	/* Device supports WDTR messages */
162 	unsigned ppr:1;		/* Device supports PPR messages */
163 	unsigned tagged_supported:1;	/* Supports SCSI-II tagged queuing */
164 	unsigned simple_tags:1;	/* simple queue tag messages are enabled */
165 	unsigned was_reset:1;	/* There was a bus reset on the bus for
166 				 * this device */
167 	unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
168 				     * because we did a bus reset. */
169 	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
170 	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
171 	unsigned no_report_opcodes:1;	/* no REPORT SUPPORTED OPERATION CODES */
172 	unsigned no_write_same:1;	/* no WRITE SAME command */
173 	unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
174 	unsigned skip_ms_page_8:1;	/* do not use MODE SENSE page 0x08 */
175 	unsigned skip_ms_page_3f:1;	/* do not use MODE SENSE page 0x3f */
176 	unsigned skip_vpd_pages:1;	/* do not read VPD pages */
177 	unsigned try_vpd_pages:1;	/* attempt to read VPD pages */
178 	unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
179 	unsigned no_start_on_add:1;	/* do not issue start on add */
180 	unsigned allow_restart:1; /* issue START_UNIT in error handler */
181 	unsigned manage_start_stop:1;	/* Let HLD (sd) manage start/stop */
182 	unsigned start_stop_pwr_cond:1;	/* Set power cond. in START_STOP_UNIT */
183 	unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
184 	unsigned select_no_atn:1;
185 	unsigned fix_capacity:1;	/* READ_CAPACITY is too high by 1 */
186 	unsigned guess_capacity:1;	/* READ_CAPACITY might be too high by 1 */
187 	unsigned retry_hwerror:1;	/* Retry HARDWARE_ERROR */
188 	unsigned last_sector_bug:1;	/* do not use multisector accesses on
189 					   SD_LAST_BUGGY_SECTORS */
190 	unsigned no_read_disc_info:1;	/* Avoid READ_DISC_INFO cmds */
191 	unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
192 	unsigned try_rc_10_first:1;	/* Try READ_CAPACACITY_10 first */
193 	unsigned security_supported:1;	/* Supports Security Protocols */
194 	unsigned is_visible:1;	/* is the device visible in sysfs */
195 	unsigned wce_default_on:1;	/* Cache is ON by default */
196 	unsigned no_dif:1;	/* T10 PI (DIF) should be disabled */
197 	unsigned broken_fua:1;		/* Don't set FUA bit */
198 	unsigned lun_in_cdb:1;		/* Store LUN bits in CDB[1] */
199 	unsigned unmap_limit_for_ws:1;	/* Use the UNMAP limit for WRITE SAME */
200 
201 	atomic_t disk_events_disable_depth; /* disable depth for disk events */
202 
203 	DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
204 	DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
205 	struct list_head event_list;	/* asserted events */
206 	struct work_struct event_work;
207 
208 	unsigned int max_device_blocked; /* what device_blocked counts down from  */
209 #define SCSI_DEFAULT_DEVICE_BLOCKED	3
210 
211 	atomic_t iorequest_cnt;
212 	atomic_t iodone_cnt;
213 	atomic_t ioerr_cnt;
214 
215 	struct device		sdev_gendev,
216 				sdev_dev;
217 
218 	struct execute_work	ew; /* used to get process context on put */
219 	struct work_struct	requeue_work;
220 
221 	struct scsi_device_handler *handler;
222 	void			*handler_data;
223 
224 	unsigned char		access_state;
225 	struct mutex		state_mutex;
226 	enum scsi_device_state sdev_state;
227 	struct task_struct	*quiesced_by;
228 	unsigned long		sdev_data[0];
229 } __attribute__((aligned(sizeof(unsigned long))));
230 
231 #define	to_scsi_device(d)	\
232 	container_of(d, struct scsi_device, sdev_gendev)
233 #define	class_to_sdev(d)	\
234 	container_of(d, struct scsi_device, sdev_dev)
235 #define transport_class_to_sdev(class_dev) \
236 	to_scsi_device(class_dev->parent)
237 
238 #define sdev_dbg(sdev, fmt, a...) \
239 	dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)
240 
241 /*
242  * like scmd_printk, but the device name is passed in
243  * as a string pointer
244  */
245 __printf(4, 5) void
246 sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
247 		const char *, ...);
248 
249 #define sdev_printk(l, sdev, fmt, a...)				\
250 	sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
251 
252 __printf(3, 4) void
253 scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
254 
255 #define scmd_dbg(scmd, fmt, a...)					   \
256 	do {								   \
257 		if ((scmd)->request->rq_disk)				   \
258 			sdev_dbg((scmd)->device, "[%s] " fmt,		   \
259 				 (scmd)->request->rq_disk->disk_name, ##a);\
260 		else							   \
261 			sdev_dbg((scmd)->device, fmt, ##a);		   \
262 	} while (0)
263 
264 enum scsi_target_state {
265 	STARGET_CREATED = 1,
266 	STARGET_RUNNING,
267 	STARGET_REMOVE,
268 	STARGET_CREATED_REMOVE,
269 	STARGET_DEL,
270 };
271 
272 /*
273  * scsi_target: representation of a scsi target, for now, this is only
274  * used for single_lun devices. If no one has active IO to the target,
275  * starget_sdev_user is NULL, else it points to the active sdev.
276  */
277 struct scsi_target {
278 	struct scsi_device	*starget_sdev_user;
279 	struct list_head	siblings;
280 	struct list_head	devices;
281 	struct device		dev;
282 	struct kref		reap_ref; /* last put renders target invisible */
283 	unsigned int		channel;
284 	unsigned int		id; /* target id ... replace
285 				     * scsi_device.id eventually */
286 	unsigned int		create:1; /* signal that it needs to be added */
287 	unsigned int		single_lun:1;	/* Indicates we should only
288 						 * allow I/O to one of the luns
289 						 * for the device at a time. */
290 	unsigned int		pdt_1f_for_no_lun:1;	/* PDT = 0x1f
291 						 * means no lun present. */
292 	unsigned int		no_report_luns:1;	/* Don't use
293 						 * REPORT LUNS for scanning. */
294 	unsigned int		expecting_lun_change:1;	/* A device has reported
295 						 * a 3F/0E UA, other devices on
296 						 * the same target will also. */
297 	/* commands actually active on LLD. */
298 	atomic_t		target_busy;
299 	atomic_t		target_blocked;
300 
301 	/*
302 	 * LLDs should set this in the slave_alloc host template callout.
303 	 * If set to zero then there is not limit.
304 	 */
305 	unsigned int		can_queue;
306 	unsigned int		max_target_blocked;
307 #define SCSI_DEFAULT_TARGET_BLOCKED	3
308 
309 	char			scsi_level;
310 	enum scsi_target_state	state;
311 	void 			*hostdata; /* available to low-level driver */
312 	unsigned long		starget_data[0]; /* for the transport */
313 	/* starget_data must be the last element!!!! */
314 } __attribute__((aligned(sizeof(unsigned long))));
315 
316 #define to_scsi_target(d)	container_of(d, struct scsi_target, dev)
317 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
318 {
319 	return to_scsi_target(sdev->sdev_gendev.parent);
320 }
321 #define transport_class_to_starget(class_dev) \
322 	to_scsi_target(class_dev->parent)
323 
324 #define starget_printk(prefix, starget, fmt, a...)	\
325 	dev_printk(prefix, &(starget)->dev, fmt, ##a)
326 
327 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
328 		uint, uint, u64, void *hostdata);
329 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
330 			   uint target, u64 lun);
331 extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
332 extern void scsi_remove_device(struct scsi_device *);
333 extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
334 void scsi_attach_vpd(struct scsi_device *sdev);
335 
336 extern struct scsi_device *scsi_device_from_queue(struct request_queue *q);
337 extern int __must_check scsi_device_get(struct scsi_device *);
338 extern void scsi_device_put(struct scsi_device *);
339 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
340 					      uint, uint, u64);
341 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
342 						uint, uint, u64);
343 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
344 							u64);
345 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
346 							  u64);
347 extern void starget_for_each_device(struct scsi_target *, void *,
348 		     void (*fn)(struct scsi_device *, void *));
349 extern void __starget_for_each_device(struct scsi_target *, void *,
350 				      void (*fn)(struct scsi_device *,
351 						 void *));
352 
353 /* only exposed to implement shost_for_each_device */
354 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
355 						  struct scsi_device *);
356 
357 /**
358  * shost_for_each_device - iterate over all devices of a host
359  * @sdev: the &struct scsi_device to use as a cursor
360  * @shost: the &struct scsi_host to iterate over
361  *
362  * Iterator that returns each device attached to @shost.  This loop
363  * takes a reference on each device and releases it at the end.  If
364  * you break out of the loop, you must call scsi_device_put(sdev).
365  */
366 #define shost_for_each_device(sdev, shost) \
367 	for ((sdev) = __scsi_iterate_devices((shost), NULL); \
368 	     (sdev); \
369 	     (sdev) = __scsi_iterate_devices((shost), (sdev)))
370 
371 /**
372  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
373  * @sdev: the &struct scsi_device to use as a cursor
374  * @shost: the &struct scsi_host to iterate over
375  *
376  * Iterator that returns each device attached to @shost.  It does _not_
377  * take a reference on the scsi_device, so the whole loop must be
378  * protected by shost->host_lock.
379  *
380  * Note: The only reason to use this is because you need to access the
381  * device list in interrupt context.  Otherwise you really want to use
382  * shost_for_each_device instead.
383  */
384 #define __shost_for_each_device(sdev, shost) \
385 	list_for_each_entry((sdev), &((shost)->__devices), siblings)
386 
387 extern int scsi_change_queue_depth(struct scsi_device *, int);
388 extern int scsi_track_queue_full(struct scsi_device *, int);
389 
390 extern int scsi_set_medium_removal(struct scsi_device *, char);
391 
392 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
393 			   unsigned char *buffer, int len, int timeout,
394 			   int retries, struct scsi_mode_data *data,
395 			   struct scsi_sense_hdr *);
396 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
397 			    int modepage, unsigned char *buffer, int len,
398 			    int timeout, int retries,
399 			    struct scsi_mode_data *data,
400 			    struct scsi_sense_hdr *);
401 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
402 				int retries, struct scsi_sense_hdr *sshdr);
403 extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
404 			     int buf_len);
405 extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
406 			      unsigned int len, unsigned char opcode);
407 extern int scsi_device_set_state(struct scsi_device *sdev,
408 				 enum scsi_device_state state);
409 extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
410 					  gfp_t gfpflags);
411 extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
412 extern void sdev_evt_send_simple(struct scsi_device *sdev,
413 			  enum scsi_device_event evt_type, gfp_t gfpflags);
414 extern int scsi_device_quiesce(struct scsi_device *sdev);
415 extern void scsi_device_resume(struct scsi_device *sdev);
416 extern void scsi_target_quiesce(struct scsi_target *);
417 extern void scsi_target_resume(struct scsi_target *);
418 extern void scsi_scan_target(struct device *parent, unsigned int channel,
419 			     unsigned int id, u64 lun,
420 			     enum scsi_scan_mode rescan);
421 extern void scsi_target_reap(struct scsi_target *);
422 extern void scsi_target_block(struct device *);
423 extern void scsi_target_unblock(struct device *, enum scsi_device_state);
424 extern void scsi_remove_target(struct device *);
425 extern const char *scsi_device_state_name(enum scsi_device_state);
426 extern int scsi_is_sdev_device(const struct device *);
427 extern int scsi_is_target_device(const struct device *);
428 extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
429 extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
430 			int data_direction, void *buffer, unsigned bufflen,
431 			unsigned char *sense, struct scsi_sense_hdr *sshdr,
432 			int timeout, int retries, u64 flags,
433 			req_flags_t rq_flags, int *resid);
434 static inline int scsi_execute_req(struct scsi_device *sdev,
435 	const unsigned char *cmd, int data_direction, void *buffer,
436 	unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
437 	int retries, int *resid)
438 {
439 	return scsi_execute(sdev, cmd, data_direction, buffer,
440 		bufflen, NULL, sshdr, timeout, retries,  0, 0, resid);
441 }
442 extern void sdev_disable_disk_events(struct scsi_device *sdev);
443 extern void sdev_enable_disk_events(struct scsi_device *sdev);
444 extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
445 extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
446 
447 #ifdef CONFIG_PM
448 extern int scsi_autopm_get_device(struct scsi_device *);
449 extern void scsi_autopm_put_device(struct scsi_device *);
450 #else
451 static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
452 static inline void scsi_autopm_put_device(struct scsi_device *d) {}
453 #endif /* CONFIG_PM */
454 
455 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
456 {
457 	return device_reprobe(&sdev->sdev_gendev);
458 }
459 
460 static inline unsigned int sdev_channel(struct scsi_device *sdev)
461 {
462 	return sdev->channel;
463 }
464 
465 static inline unsigned int sdev_id(struct scsi_device *sdev)
466 {
467 	return sdev->id;
468 }
469 
470 #define scmd_id(scmd) sdev_id((scmd)->device)
471 #define scmd_channel(scmd) sdev_channel((scmd)->device)
472 
473 /*
474  * checks for positions of the SCSI state machine
475  */
476 static inline int scsi_device_online(struct scsi_device *sdev)
477 {
478 	return (sdev->sdev_state != SDEV_OFFLINE &&
479 		sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
480 		sdev->sdev_state != SDEV_DEL);
481 }
482 static inline int scsi_device_blocked(struct scsi_device *sdev)
483 {
484 	return sdev->sdev_state == SDEV_BLOCK ||
485 		sdev->sdev_state == SDEV_CREATED_BLOCK;
486 }
487 static inline int scsi_device_created(struct scsi_device *sdev)
488 {
489 	return sdev->sdev_state == SDEV_CREATED ||
490 		sdev->sdev_state == SDEV_CREATED_BLOCK;
491 }
492 
493 int scsi_internal_device_block_nowait(struct scsi_device *sdev);
494 int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
495 					enum scsi_device_state new_state);
496 
497 /* accessor functions for the SCSI parameters */
498 static inline int scsi_device_sync(struct scsi_device *sdev)
499 {
500 	return sdev->sdtr;
501 }
502 static inline int scsi_device_wide(struct scsi_device *sdev)
503 {
504 	return sdev->wdtr;
505 }
506 static inline int scsi_device_dt(struct scsi_device *sdev)
507 {
508 	return sdev->ppr;
509 }
510 static inline int scsi_device_dt_only(struct scsi_device *sdev)
511 {
512 	if (sdev->inquiry_len < 57)
513 		return 0;
514 	return (sdev->inquiry[56] & 0x0c) == 0x04;
515 }
516 static inline int scsi_device_ius(struct scsi_device *sdev)
517 {
518 	if (sdev->inquiry_len < 57)
519 		return 0;
520 	return sdev->inquiry[56] & 0x01;
521 }
522 static inline int scsi_device_qas(struct scsi_device *sdev)
523 {
524 	if (sdev->inquiry_len < 57)
525 		return 0;
526 	return sdev->inquiry[56] & 0x02;
527 }
528 static inline int scsi_device_enclosure(struct scsi_device *sdev)
529 {
530 	return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
531 }
532 
533 static inline int scsi_device_protection(struct scsi_device *sdev)
534 {
535 	if (sdev->no_dif)
536 		return 0;
537 
538 	return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
539 }
540 
541 static inline int scsi_device_tpgs(struct scsi_device *sdev)
542 {
543 	return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
544 }
545 
546 /**
547  * scsi_device_supports_vpd - test if a device supports VPD pages
548  * @sdev: the &struct scsi_device to test
549  *
550  * If the 'try_vpd_pages' flag is set it takes precedence.
551  * Otherwise we will assume VPD pages are supported if the
552  * SCSI level is at least SPC-3 and 'skip_vpd_pages' is not set.
553  */
554 static inline int scsi_device_supports_vpd(struct scsi_device *sdev)
555 {
556 	/* Attempt VPD inquiry if the device blacklist explicitly calls
557 	 * for it.
558 	 */
559 	if (sdev->try_vpd_pages)
560 		return 1;
561 	/*
562 	 * Although VPD inquiries can go to SCSI-2 type devices,
563 	 * some USB ones crash on receiving them, and the pages
564 	 * we currently ask for are mandatory for SPC-2 and beyond
565 	 */
566 	if (sdev->scsi_level >= SCSI_SPC_2 && !sdev->skip_vpd_pages)
567 		return 1;
568 	return 0;
569 }
570 
571 #define MODULE_ALIAS_SCSI_DEVICE(type) \
572 	MODULE_ALIAS("scsi:t-" __stringify(type) "*")
573 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
574 
575 #endif /* _SCSI_SCSI_DEVICE_H */
576