xref: /linux/include/scsi/scsi_device.h (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
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 <asm/atomic.h>
8 
9 struct request_queue;
10 struct scsi_cmnd;
11 struct scsi_lun;
12 struct scsi_sense_hdr;
13 
14 struct scsi_mode_data {
15 	__u32	length;
16 	__u16	block_descriptor_length;
17 	__u8	medium_type;
18 	__u8	device_specific;
19 	__u8	header_length;
20 	__u8	longlba:1;
21 };
22 
23 /*
24  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
25  * (for the ascii descriptions) and the state model enforcer:
26  * scsi_lib:scsi_device_set_state().
27  */
28 enum scsi_device_state {
29 	SDEV_CREATED = 1,	/* device created but not added to sysfs
30 				 * Only internal commands allowed (for inq) */
31 	SDEV_RUNNING,		/* device properly configured
32 				 * All commands allowed */
33 	SDEV_CANCEL,		/* beginning to delete device
34 				 * Only error handler commands allowed */
35 	SDEV_DEL,		/* device deleted
36 				 * no commands allowed */
37 	SDEV_QUIESCE,		/* Device quiescent.  No block commands
38 				 * will be accepted, only specials (which
39 				 * originate in the mid-layer) */
40 	SDEV_OFFLINE,		/* Device offlined (by error handling or
41 				 * user request */
42 	SDEV_BLOCK,		/* Device blocked by scsi lld.  No scsi
43 				 * commands from user or midlayer should be issued
44 				 * to the scsi lld. */
45 };
46 
47 struct scsi_device {
48 	struct Scsi_Host *host;
49 	struct request_queue *request_queue;
50 
51 	/* the next two are protected by the host->host_lock */
52 	struct list_head    siblings;   /* list of all devices on this host */
53 	struct list_head    same_target_siblings; /* just the devices sharing same target id */
54 
55 	/* this is now protected by the request_queue->queue_lock */
56 	unsigned int device_busy;	/* commands actually active on
57 					 * low-level. protected by queue_lock. */
58 	spinlock_t list_lock;
59 	struct list_head cmd_list;	/* queue of in use SCSI Command structures */
60 	struct list_head starved_entry;
61 	struct scsi_cmnd *current_cmnd;	/* currently active command */
62 	unsigned short queue_depth;	/* How deep of a queue we want */
63 	unsigned short last_queue_full_depth; /* These two are used by */
64 	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
65 	unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
66 					   jiffie count on our counter, they
67 					   could all be from the same event. */
68 
69 	unsigned int id, lun, channel;
70 
71 	unsigned int manufacturer;	/* Manufacturer of device, for using
72 					 * vendor-specific cmd's */
73 	unsigned sector_size;	/* size in bytes */
74 
75 	void *hostdata;		/* available to low-level driver */
76 	char devfs_name[256];	/* devfs junk */
77 	char type;
78 	char scsi_level;
79 	char inq_periph_qual;	/* PQ from INQUIRY data */
80 	unsigned char inquiry_len;	/* valid bytes in 'inquiry' */
81 	unsigned char * inquiry;	/* INQUIRY response data */
82 	char * vendor;		/* [back_compat] point into 'inquiry' ... */
83 	char * model;		/* ... after scan; point to static string */
84 	char * rev;		/* ... "nullnullnullnull" before scan */
85 	unsigned char current_tag;	/* current tag */
86 	struct scsi_target      *sdev_target;   /* used only for single_lun */
87 
88 	unsigned int	sdev_bflags; /* black/white flags as also found in
89 				 * scsi_devinfo.[hc]. For now used only to
90 				 * pass settings from slave_alloc to scsi
91 				 * core. */
92 	unsigned writeable:1;
93 	unsigned removable:1;
94 	unsigned changed:1;	/* Data invalid due to media change */
95 	unsigned busy:1;	/* Used to prevent races */
96 	unsigned lockable:1;	/* Able to prevent media removal */
97 	unsigned locked:1;      /* Media removal disabled */
98 	unsigned borken:1;	/* Tell the Seagate driver to be
99 				 * painfully slow on this device */
100 	unsigned disconnect:1;	/* can disconnect */
101 	unsigned soft_reset:1;	/* Uses soft reset option */
102 	unsigned sdtr:1;	/* Device supports SDTR messages */
103 	unsigned wdtr:1;	/* Device supports WDTR messages */
104 	unsigned ppr:1;		/* Device supports PPR messages */
105 	unsigned tagged_supported:1;	/* Supports SCSI-II tagged queuing */
106 	unsigned simple_tags:1;	/* simple queue tag messages are enabled */
107 	unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
108 	unsigned single_lun:1;	/* Indicates we should only allow I/O to
109 				 * one of the luns for the device at a
110 				 * time. */
111 	unsigned was_reset:1;	/* There was a bus reset on the bus for
112 				 * this device */
113 	unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
114 				     * because we did a bus reset. */
115 	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
116 	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
117 	unsigned skip_ms_page_8:1;	/* do not use MODE SENSE page 0x08 */
118 	unsigned skip_ms_page_3f:1;	/* do not use MODE SENSE page 0x3f */
119 	unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
120 	unsigned no_start_on_add:1;	/* do not issue start on add */
121 	unsigned allow_restart:1; /* issue START_UNIT in error handler */
122 	unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
123 	unsigned select_no_atn:1;
124 	unsigned fix_capacity:1;	/* READ_CAPACITY is too high by 1 */
125 	unsigned retry_hwerror:1;	/* Retry HARDWARE_ERROR */
126 
127 	unsigned int device_blocked;	/* Device returned QUEUE_FULL. */
128 
129 	unsigned int max_device_blocked; /* what device_blocked counts down from  */
130 #define SCSI_DEFAULT_DEVICE_BLOCKED	3
131 
132 	atomic_t iorequest_cnt;
133 	atomic_t iodone_cnt;
134 	atomic_t ioerr_cnt;
135 
136 	int timeout;
137 
138 	struct device		sdev_gendev;
139 	struct class_device	sdev_classdev;
140 
141 	enum scsi_device_state sdev_state;
142 	unsigned long		sdev_data[0];
143 } __attribute__((aligned(sizeof(unsigned long))));
144 #define	to_scsi_device(d)	\
145 	container_of(d, struct scsi_device, sdev_gendev)
146 #define	class_to_sdev(d)	\
147 	container_of(d, struct scsi_device, sdev_classdev)
148 #define transport_class_to_sdev(class_dev) \
149 	to_scsi_device(class_dev->dev)
150 
151 /*
152  * scsi_target: representation of a scsi target, for now, this is only
153  * used for single_lun devices. If no one has active IO to the target,
154  * starget_sdev_user is NULL, else it points to the active sdev.
155  */
156 struct scsi_target {
157 	struct scsi_device	*starget_sdev_user;
158 	struct list_head	siblings;
159 	struct list_head	devices;
160 	struct device		dev;
161 	unsigned int		reap_ref; /* protected by the host lock */
162 	unsigned int		channel;
163 	unsigned int		id; /* target id ... replace
164 				     * scsi_device.id eventually */
165 	unsigned long		create:1; /* signal that it needs to be added */
166 	char			scsi_level;
167 	void 			*hostdata; /* available to low-level driver */
168 	unsigned long		starget_data[0]; /* for the transport */
169 	/* starget_data must be the last element!!!! */
170 } __attribute__((aligned(sizeof(unsigned long))));
171 
172 #define to_scsi_target(d)	container_of(d, struct scsi_target, dev)
173 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
174 {
175 	return to_scsi_target(sdev->sdev_gendev.parent);
176 }
177 #define transport_class_to_starget(class_dev) \
178 	to_scsi_target(class_dev->dev)
179 
180 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
181 		uint, uint, uint, void *hostdata);
182 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
183 			   uint target, uint lun);
184 extern void scsi_remove_device(struct scsi_device *);
185 extern int scsi_device_cancel(struct scsi_device *, int);
186 
187 extern int scsi_device_get(struct scsi_device *);
188 extern void scsi_device_put(struct scsi_device *);
189 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
190 					      uint, uint, uint);
191 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
192 						uint, uint, uint);
193 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
194 							uint);
195 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
196 							  uint);
197 extern void starget_for_each_device(struct scsi_target *, void *,
198 		     void (*fn)(struct scsi_device *, void *));
199 
200 /* only exposed to implement shost_for_each_device */
201 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
202 						  struct scsi_device *);
203 
204 /**
205  * shost_for_each_device  -  iterate over all devices of a host
206  * @sdev:	iterator
207  * @host:	host whiches devices we want to iterate over
208  *
209  * This traverses over each devices of @shost.  The devices have
210  * a reference that must be released by scsi_host_put when breaking
211  * out of the loop.
212  */
213 #define shost_for_each_device(sdev, shost) \
214 	for ((sdev) = __scsi_iterate_devices((shost), NULL); \
215 	     (sdev); \
216 	     (sdev) = __scsi_iterate_devices((shost), (sdev)))
217 
218 /**
219  * __shost_for_each_device  -  iterate over all devices of a host (UNLOCKED)
220  * @sdev:	iterator
221  * @host:	host whiches devices we want to iterate over
222  *
223  * This traverses over each devices of @shost.  It does _not_ take a
224  * reference on the scsi_device, thus it the whole loop must be protected
225  * by shost->host_lock.
226  *
227  * Note:  The only reason why drivers would want to use this is because
228  * they're need to access the device list in irq context.  Otherwise you
229  * really want to use shost_for_each_device instead.
230  */
231 #define __shost_for_each_device(sdev, shost) \
232 	list_for_each_entry((sdev), &((shost)->__devices), siblings)
233 
234 extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
235 extern int scsi_track_queue_full(struct scsi_device *, int);
236 
237 extern int scsi_set_medium_removal(struct scsi_device *, char);
238 
239 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
240 			   unsigned char *buffer, int len, int timeout,
241 			   int retries, struct scsi_mode_data *data,
242 			   struct scsi_sense_hdr *);
243 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
244 				int retries);
245 extern int scsi_device_set_state(struct scsi_device *sdev,
246 				 enum scsi_device_state state);
247 extern int scsi_device_quiesce(struct scsi_device *sdev);
248 extern void scsi_device_resume(struct scsi_device *sdev);
249 extern void scsi_target_quiesce(struct scsi_target *);
250 extern void scsi_target_resume(struct scsi_target *);
251 extern void scsi_scan_target(struct device *parent, unsigned int channel,
252 			     unsigned int id, unsigned int lun, int rescan);
253 extern void scsi_target_reap(struct scsi_target *);
254 extern void scsi_target_block(struct device *);
255 extern void scsi_target_unblock(struct device *);
256 extern void scsi_remove_target(struct device *);
257 extern void int_to_scsilun(unsigned int, struct scsi_lun *);
258 extern const char *scsi_device_state_name(enum scsi_device_state);
259 extern int scsi_is_sdev_device(const struct device *);
260 extern int scsi_is_target_device(const struct device *);
261 extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
262 			int data_direction, void *buffer, unsigned bufflen,
263 			unsigned char *sense, int timeout, int retries,
264 			int flag);
265 extern int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
266 			    int data_direction, void *buffer, unsigned bufflen,
267 			    struct scsi_sense_hdr *, int timeout, int retries);
268 
269 static inline int scsi_device_online(struct scsi_device *sdev)
270 {
271 	return sdev->sdev_state != SDEV_OFFLINE;
272 }
273 
274 /* accessor functions for the SCSI parameters */
275 static inline int scsi_device_sync(struct scsi_device *sdev)
276 {
277 	return sdev->sdtr;
278 }
279 static inline int scsi_device_wide(struct scsi_device *sdev)
280 {
281 	return sdev->wdtr;
282 }
283 static inline int scsi_device_dt(struct scsi_device *sdev)
284 {
285 	return sdev->ppr;
286 }
287 static inline int scsi_device_dt_only(struct scsi_device *sdev)
288 {
289 	if (sdev->inquiry_len < 57)
290 		return 0;
291 	return (sdev->inquiry[56] & 0x0c) == 0x04;
292 }
293 static inline int scsi_device_ius(struct scsi_device *sdev)
294 {
295 	if (sdev->inquiry_len < 57)
296 		return 0;
297 	return sdev->inquiry[56] & 0x01;
298 }
299 static inline int scsi_device_qas(struct scsi_device *sdev)
300 {
301 	if (sdev->inquiry_len < 57)
302 		return 0;
303 	return sdev->inquiry[56] & 0x02;
304 }
305 #endif /* _SCSI_SCSI_DEVICE_H */
306