xref: /linux/include/scsi/scsi_device.h (revision 2d6ffcca623a9a16df6cdfbe8250b7a5904a5f5e)
1 #ifndef _SCSI_SCSI_DEVICE_H
2 #define _SCSI_SCSI_DEVICE_H
3 
4 #include <linux/device.h>
5 #include <linux/list.h>
6 #include <linux/spinlock.h>
7 #include <linux/workqueue.h>
8 #include <linux/blkdev.h>
9 #include <asm/atomic.h>
10 
11 struct request_queue;
12 struct scsi_cmnd;
13 struct scsi_lun;
14 struct scsi_sense_hdr;
15 
16 struct scsi_mode_data {
17 	__u32	length;
18 	__u16	block_descriptor_length;
19 	__u8	medium_type;
20 	__u8	device_specific;
21 	__u8	header_length;
22 	__u8	longlba:1;
23 };
24 
25 /*
26  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
27  * (for the ascii descriptions) and the state model enforcer:
28  * scsi_lib:scsi_device_set_state().
29  */
30 enum scsi_device_state {
31 	SDEV_CREATED = 1,	/* device created but not added to sysfs
32 				 * Only internal commands allowed (for inq) */
33 	SDEV_RUNNING,		/* device properly configured
34 				 * All commands allowed */
35 	SDEV_CANCEL,		/* beginning to delete device
36 				 * Only error handler commands allowed */
37 	SDEV_DEL,		/* device deleted
38 				 * no commands allowed */
39 	SDEV_QUIESCE,		/* Device quiescent.  No block commands
40 				 * will be accepted, only specials (which
41 				 * originate in the mid-layer) */
42 	SDEV_OFFLINE,		/* Device offlined (by error handling or
43 				 * user request */
44 	SDEV_BLOCK,		/* Device blocked by scsi lld.  No scsi
45 				 * commands from user or midlayer should be issued
46 				 * to the scsi lld. */
47 };
48 
49 enum scsi_device_event {
50 	SDEV_EVT_MEDIA_CHANGE	= 1,	/* media has changed */
51 
52 	SDEV_EVT_LAST		= SDEV_EVT_MEDIA_CHANGE,
53 	SDEV_EVT_MAXBITS	= SDEV_EVT_LAST + 1
54 };
55 
56 struct scsi_event {
57 	enum scsi_device_event	evt_type;
58 	struct list_head	node;
59 
60 	/* put union of data structures, for non-simple event types,
61 	 * here
62 	 */
63 };
64 
65 struct scsi_device {
66 	struct Scsi_Host *host;
67 	struct request_queue *request_queue;
68 
69 	/* the next two are protected by the host->host_lock */
70 	struct list_head    siblings;   /* list of all devices on this host */
71 	struct list_head    same_target_siblings; /* just the devices sharing same target id */
72 
73 	/* this is now protected by the request_queue->queue_lock */
74 	unsigned int device_busy;	/* commands actually active on
75 					 * low-level. protected by queue_lock. */
76 	spinlock_t list_lock;
77 	struct list_head cmd_list;	/* queue of in use SCSI Command structures */
78 	struct list_head starved_entry;
79 	struct scsi_cmnd *current_cmnd;	/* currently active command */
80 	unsigned short queue_depth;	/* How deep of a queue we want */
81 	unsigned short last_queue_full_depth; /* These two are used by */
82 	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
83 	unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
84 					   jiffie count on our counter, they
85 					   could all be from the same event. */
86 
87 	unsigned int id, lun, channel;
88 
89 	unsigned int manufacturer;	/* Manufacturer of device, for using
90 					 * vendor-specific cmd's */
91 	unsigned sector_size;	/* size in bytes */
92 
93 	void *hostdata;		/* available to low-level driver */
94 	char type;
95 	char scsi_level;
96 	char inq_periph_qual;	/* PQ from INQUIRY data */
97 	unsigned char inquiry_len;	/* valid bytes in 'inquiry' */
98 	unsigned char * inquiry;	/* INQUIRY response data */
99 	const char * vendor;		/* [back_compat] point into 'inquiry' ... */
100 	const char * model;		/* ... after scan; point to static string */
101 	const char * rev;		/* ... "nullnullnullnull" before scan */
102 	unsigned char current_tag;	/* current tag */
103 	struct scsi_target      *sdev_target;   /* used only for single_lun */
104 
105 	unsigned int	sdev_bflags; /* black/white flags as also found in
106 				 * scsi_devinfo.[hc]. For now used only to
107 				 * pass settings from slave_alloc to scsi
108 				 * core. */
109 	unsigned writeable:1;
110 	unsigned removable:1;
111 	unsigned changed:1;	/* Data invalid due to media change */
112 	unsigned busy:1;	/* Used to prevent races */
113 	unsigned lockable:1;	/* Able to prevent media removal */
114 	unsigned locked:1;      /* Media removal disabled */
115 	unsigned borken:1;	/* Tell the Seagate driver to be
116 				 * painfully slow on this device */
117 	unsigned disconnect:1;	/* can disconnect */
118 	unsigned soft_reset:1;	/* Uses soft reset option */
119 	unsigned sdtr:1;	/* Device supports SDTR messages */
120 	unsigned wdtr:1;	/* Device supports WDTR messages */
121 	unsigned ppr:1;		/* Device supports PPR messages */
122 	unsigned tagged_supported:1;	/* Supports SCSI-II tagged queuing */
123 	unsigned simple_tags:1;	/* simple queue tag messages are enabled */
124 	unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
125 	unsigned was_reset:1;	/* There was a bus reset on the bus for
126 				 * this device */
127 	unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
128 				     * because we did a bus reset. */
129 	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
130 	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
131 	unsigned skip_ms_page_8:1;	/* do not use MODE SENSE page 0x08 */
132 	unsigned skip_ms_page_3f:1;	/* do not use MODE SENSE page 0x3f */
133 	unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
134 	unsigned no_start_on_add:1;	/* do not issue start on add */
135 	unsigned allow_restart:1; /* issue START_UNIT in error handler */
136 	unsigned manage_start_stop:1;	/* Let HLD (sd) manage start/stop */
137 	unsigned start_stop_pwr_cond:1;	/* Set power cond. in START_STOP_UNIT */
138 	unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
139 	unsigned select_no_atn:1;
140 	unsigned fix_capacity:1;	/* READ_CAPACITY is too high by 1 */
141 	unsigned guess_capacity:1;	/* READ_CAPACITY might be too high by 1 */
142 	unsigned retry_hwerror:1;	/* Retry HARDWARE_ERROR */
143 	unsigned last_sector_bug:1;	/* Always read last sector in a 1 sector read */
144 
145 	DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
146 	struct list_head event_list;	/* asserted events */
147 	struct work_struct event_work;
148 
149 	unsigned int device_blocked;	/* Device returned QUEUE_FULL. */
150 
151 	unsigned int max_device_blocked; /* what device_blocked counts down from  */
152 #define SCSI_DEFAULT_DEVICE_BLOCKED	3
153 
154 	atomic_t iorequest_cnt;
155 	atomic_t iodone_cnt;
156 	atomic_t ioerr_cnt;
157 
158 	int timeout;
159 
160 	struct device		sdev_gendev,
161 				sdev_dev;
162 
163 	struct execute_work	ew; /* used to get process context on put */
164 
165 	struct scsi_dh_data	*scsi_dh_data;
166 	enum scsi_device_state sdev_state;
167 	unsigned long		sdev_data[0];
168 } __attribute__((aligned(sizeof(unsigned long))));
169 
170 struct scsi_device_handler {
171 	/* Used by the infrastructure */
172 	struct list_head list; /* list of scsi_device_handlers */
173 	struct notifier_block nb;
174 
175 	/* Filled by the hardware handler */
176 	struct module *module;
177 	const char *name;
178 	int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *);
179 	int (*activate)(struct scsi_device *);
180 	int (*prep_fn)(struct scsi_device *, struct request *);
181 };
182 
183 struct scsi_dh_data {
184 	struct scsi_device_handler *scsi_dh;
185 	char buf[0];
186 };
187 
188 #define	to_scsi_device(d)	\
189 	container_of(d, struct scsi_device, sdev_gendev)
190 #define	class_to_sdev(d)	\
191 	container_of(d, struct scsi_device, sdev_dev)
192 #define transport_class_to_sdev(class_dev) \
193 	to_scsi_device(class_dev->parent)
194 
195 #define sdev_printk(prefix, sdev, fmt, a...)	\
196 	dev_printk(prefix, &(sdev)->sdev_gendev, fmt, ##a)
197 
198 #define scmd_printk(prefix, scmd, fmt, a...)				\
199         (scmd)->request->rq_disk ?					\
200 	sdev_printk(prefix, (scmd)->device, "[%s] " fmt,		\
201 		    (scmd)->request->rq_disk->disk_name, ##a) :		\
202 	sdev_printk(prefix, (scmd)->device, fmt, ##a)
203 
204 enum scsi_target_state {
205 	STARGET_CREATED = 1,
206 	STARGET_RUNNING,
207 	STARGET_DEL,
208 };
209 
210 /*
211  * scsi_target: representation of a scsi target, for now, this is only
212  * used for single_lun devices. If no one has active IO to the target,
213  * starget_sdev_user is NULL, else it points to the active sdev.
214  */
215 struct scsi_target {
216 	struct scsi_device	*starget_sdev_user;
217 	struct list_head	siblings;
218 	struct list_head	devices;
219 	struct device		dev;
220 	unsigned int		reap_ref; /* protected by the host lock */
221 	unsigned int		channel;
222 	unsigned int		id; /* target id ... replace
223 				     * scsi_device.id eventually */
224 	unsigned int		create:1; /* signal that it needs to be added */
225 	unsigned int		single_lun:1;	/* Indicates we should only
226 						 * allow I/O to one of the luns
227 						 * for the device at a time. */
228 	unsigned int		pdt_1f_for_no_lun;	/* PDT = 0x1f */
229 						/* means no lun present */
230 
231 	char			scsi_level;
232 	struct execute_work	ew;
233 	enum scsi_target_state	state;
234 	void 			*hostdata; /* available to low-level driver */
235 	unsigned long		starget_data[0]; /* for the transport */
236 	/* starget_data must be the last element!!!! */
237 } __attribute__((aligned(sizeof(unsigned long))));
238 
239 #define to_scsi_target(d)	container_of(d, struct scsi_target, dev)
240 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
241 {
242 	return to_scsi_target(sdev->sdev_gendev.parent);
243 }
244 #define transport_class_to_starget(class_dev) \
245 	to_scsi_target(class_dev->parent)
246 
247 #define starget_printk(prefix, starget, fmt, a...)	\
248 	dev_printk(prefix, &(starget)->dev, fmt, ##a)
249 
250 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
251 		uint, uint, uint, void *hostdata);
252 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
253 			   uint target, uint lun);
254 extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
255 extern void scsi_remove_device(struct scsi_device *);
256 extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
257 
258 extern int scsi_device_get(struct scsi_device *);
259 extern void scsi_device_put(struct scsi_device *);
260 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
261 					      uint, uint, uint);
262 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
263 						uint, uint, uint);
264 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
265 							uint);
266 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
267 							  uint);
268 extern void starget_for_each_device(struct scsi_target *, void *,
269 		     void (*fn)(struct scsi_device *, void *));
270 extern void __starget_for_each_device(struct scsi_target *, void *,
271 				      void (*fn)(struct scsi_device *,
272 						 void *));
273 
274 /* only exposed to implement shost_for_each_device */
275 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
276 						  struct scsi_device *);
277 
278 /**
279  * shost_for_each_device - iterate over all devices of a host
280  * @sdev: the &struct scsi_device to use as a cursor
281  * @shost: the &struct scsi_host to iterate over
282  *
283  * Iterator that returns each device attached to @shost.  This loop
284  * takes a reference on each device and releases it at the end.  If
285  * you break out of the loop, you must call scsi_device_put(sdev).
286  */
287 #define shost_for_each_device(sdev, shost) \
288 	for ((sdev) = __scsi_iterate_devices((shost), NULL); \
289 	     (sdev); \
290 	     (sdev) = __scsi_iterate_devices((shost), (sdev)))
291 
292 /**
293  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
294  * @sdev: the &struct scsi_device to use as a cursor
295  * @shost: the &struct scsi_host to iterate over
296  *
297  * Iterator that returns each device attached to @shost.  It does _not_
298  * take a reference on the scsi_device, so the whole loop must be
299  * protected by shost->host_lock.
300  *
301  * Note: The only reason to use this is because you need to access the
302  * device list in interrupt context.  Otherwise you really want to use
303  * shost_for_each_device instead.
304  */
305 #define __shost_for_each_device(sdev, shost) \
306 	list_for_each_entry((sdev), &((shost)->__devices), siblings)
307 
308 extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
309 extern int scsi_track_queue_full(struct scsi_device *, int);
310 
311 extern int scsi_set_medium_removal(struct scsi_device *, char);
312 
313 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
314 			   unsigned char *buffer, int len, int timeout,
315 			   int retries, struct scsi_mode_data *data,
316 			   struct scsi_sense_hdr *);
317 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
318 			    int modepage, unsigned char *buffer, int len,
319 			    int timeout, int retries,
320 			    struct scsi_mode_data *data,
321 			    struct scsi_sense_hdr *);
322 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
323 				int retries, struct scsi_sense_hdr *sshdr);
324 extern int scsi_device_set_state(struct scsi_device *sdev,
325 				 enum scsi_device_state state);
326 extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
327 					  gfp_t gfpflags);
328 extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
329 extern void sdev_evt_send_simple(struct scsi_device *sdev,
330 			  enum scsi_device_event evt_type, gfp_t gfpflags);
331 extern int scsi_device_quiesce(struct scsi_device *sdev);
332 extern void scsi_device_resume(struct scsi_device *sdev);
333 extern void scsi_target_quiesce(struct scsi_target *);
334 extern void scsi_target_resume(struct scsi_target *);
335 extern void scsi_scan_target(struct device *parent, unsigned int channel,
336 			     unsigned int id, unsigned int lun, int rescan);
337 extern void scsi_target_reap(struct scsi_target *);
338 extern void scsi_target_block(struct device *);
339 extern void scsi_target_unblock(struct device *);
340 extern void scsi_remove_target(struct device *);
341 extern void int_to_scsilun(unsigned int, struct scsi_lun *);
342 extern int scsilun_to_int(struct scsi_lun *);
343 extern const char *scsi_device_state_name(enum scsi_device_state);
344 extern int scsi_is_sdev_device(const struct device *);
345 extern int scsi_is_target_device(const struct device *);
346 extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
347 			int data_direction, void *buffer, unsigned bufflen,
348 			unsigned char *sense, int timeout, int retries,
349 			int flag);
350 extern int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
351 			    int data_direction, void *buffer, unsigned bufflen,
352 			    struct scsi_sense_hdr *, int timeout, int retries);
353 extern int scsi_execute_async(struct scsi_device *sdev,
354 			      const unsigned char *cmd, int cmd_len, int data_direction,
355 			      void *buffer, unsigned bufflen, int use_sg,
356 			      int timeout, int retries, void *privdata,
357 			      void (*done)(void *, char *, int, int),
358 			      gfp_t gfp);
359 
360 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
361 {
362 	return device_reprobe(&sdev->sdev_gendev);
363 }
364 
365 static inline unsigned int sdev_channel(struct scsi_device *sdev)
366 {
367 	return sdev->channel;
368 }
369 
370 static inline unsigned int sdev_id(struct scsi_device *sdev)
371 {
372 	return sdev->id;
373 }
374 
375 #define scmd_id(scmd) sdev_id((scmd)->device)
376 #define scmd_channel(scmd) sdev_channel((scmd)->device)
377 
378 static inline int scsi_device_online(struct scsi_device *sdev)
379 {
380 	return sdev->sdev_state != SDEV_OFFLINE;
381 }
382 
383 /* accessor functions for the SCSI parameters */
384 static inline int scsi_device_sync(struct scsi_device *sdev)
385 {
386 	return sdev->sdtr;
387 }
388 static inline int scsi_device_wide(struct scsi_device *sdev)
389 {
390 	return sdev->wdtr;
391 }
392 static inline int scsi_device_dt(struct scsi_device *sdev)
393 {
394 	return sdev->ppr;
395 }
396 static inline int scsi_device_dt_only(struct scsi_device *sdev)
397 {
398 	if (sdev->inquiry_len < 57)
399 		return 0;
400 	return (sdev->inquiry[56] & 0x0c) == 0x04;
401 }
402 static inline int scsi_device_ius(struct scsi_device *sdev)
403 {
404 	if (sdev->inquiry_len < 57)
405 		return 0;
406 	return sdev->inquiry[56] & 0x01;
407 }
408 static inline int scsi_device_qas(struct scsi_device *sdev)
409 {
410 	if (sdev->inquiry_len < 57)
411 		return 0;
412 	return sdev->inquiry[56] & 0x02;
413 }
414 static inline int scsi_device_enclosure(struct scsi_device *sdev)
415 {
416 	return sdev->inquiry[6] & (1<<6);
417 }
418 
419 #define MODULE_ALIAS_SCSI_DEVICE(type) \
420 	MODULE_ALIAS("scsi:t-" __stringify(type) "*")
421 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
422 
423 #endif /* _SCSI_SCSI_DEVICE_H */
424