xref: /linux/include/scsi/scsi_device.h (revision 776cfebb430c7b22c208b1b17add97f354d97cab)
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_mode_data;
12 
13 
14 /*
15  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
16  * (for the ascii descriptions) and the state model enforcer:
17  * scsi_lib:scsi_device_set_state().
18  */
19 enum scsi_device_state {
20 	SDEV_CREATED = 1,	/* device created but not added to sysfs
21 				 * Only internal commands allowed (for inq) */
22 	SDEV_RUNNING,		/* device properly configured
23 				 * All commands allowed */
24 	SDEV_CANCEL,		/* beginning to delete device
25 				 * Only error handler commands allowed */
26 	SDEV_DEL,		/* device deleted
27 				 * no commands allowed */
28 	SDEV_QUIESCE,		/* Device quiescent.  No block commands
29 				 * will be accepted, only specials (which
30 				 * originate in the mid-layer) */
31 	SDEV_OFFLINE,		/* Device offlined (by error handling or
32 				 * user request */
33 	SDEV_BLOCK,		/* Device blocked by scsi lld.  No scsi
34 				 * commands from user or midlayer should be issued
35 				 * to the scsi lld. */
36 };
37 
38 struct scsi_device {
39 	struct Scsi_Host *host;
40 	struct request_queue *request_queue;
41 
42 	/* the next two are protected by the host->host_lock */
43 	struct list_head    siblings;   /* list of all devices on this host */
44 	struct list_head    same_target_siblings; /* just the devices sharing same target id */
45 
46 	/* this is now protected by the request_queue->queue_lock */
47 	unsigned int device_busy;	/* commands actually active on
48 					 * low-level. protected by queue_lock. */
49 	spinlock_t list_lock;
50 	struct list_head cmd_list;	/* queue of in use SCSI Command structures */
51 	struct list_head starved_entry;
52 	struct scsi_cmnd *current_cmnd;	/* currently active command */
53 	unsigned short queue_depth;	/* How deep of a queue we want */
54 	unsigned short last_queue_full_depth; /* These two are used by */
55 	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
56 	unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
57 					   jiffie count on our counter, they
58 					   could all be from the same event. */
59 
60 	unsigned int id, lun, channel;
61 
62 	unsigned int manufacturer;	/* Manufacturer of device, for using
63 					 * vendor-specific cmd's */
64 	unsigned sector_size;	/* size in bytes */
65 
66 	void *hostdata;		/* available to low-level driver */
67 	char devfs_name[256];	/* devfs junk */
68 	char type;
69 	char scsi_level;
70 	char inq_periph_qual;	/* PQ from INQUIRY data */
71 	unsigned char inquiry_len;	/* valid bytes in 'inquiry' */
72 	unsigned char * inquiry;	/* INQUIRY response data */
73 	char * vendor;		/* [back_compat] point into 'inquiry' ... */
74 	char * model;		/* ... after scan; point to static string */
75 	char * rev;		/* ... "nullnullnullnull" before scan */
76 	unsigned char current_tag;	/* current tag */
77 	struct scsi_target      *sdev_target;   /* used only for single_lun */
78 
79 	unsigned int	sdev_bflags; /* black/white flags as also found in
80 				 * scsi_devinfo.[hc]. For now used only to
81 				 * pass settings from slave_alloc to scsi
82 				 * core. */
83 	unsigned writeable:1;
84 	unsigned removable:1;
85 	unsigned changed:1;	/* Data invalid due to media change */
86 	unsigned busy:1;	/* Used to prevent races */
87 	unsigned lockable:1;	/* Able to prevent media removal */
88 	unsigned locked:1;      /* Media removal disabled */
89 	unsigned borken:1;	/* Tell the Seagate driver to be
90 				 * painfully slow on this device */
91 	unsigned disconnect:1;	/* can disconnect */
92 	unsigned soft_reset:1;	/* Uses soft reset option */
93 	unsigned sdtr:1;	/* Device supports SDTR messages */
94 	unsigned wdtr:1;	/* Device supports WDTR messages */
95 	unsigned ppr:1;		/* Device supports PPR messages */
96 	unsigned tagged_supported:1;	/* Supports SCSI-II tagged queuing */
97 	unsigned simple_tags:1;	/* simple queue tag messages are enabled */
98 	unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
99 	unsigned single_lun:1;	/* Indicates we should only allow I/O to
100 				 * one of the luns for the device at a
101 				 * time. */
102 	unsigned was_reset:1;	/* There was a bus reset on the bus for
103 				 * this device */
104 	unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
105 				     * because we did a bus reset. */
106 	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
107 	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
108 	unsigned skip_ms_page_8:1;	/* do not use MODE SENSE page 0x08 */
109 	unsigned skip_ms_page_3f:1;	/* do not use MODE SENSE page 0x3f */
110 	unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
111 	unsigned no_start_on_add:1;	/* do not issue start on add */
112 	unsigned allow_restart:1; /* issue START_UNIT in error handler */
113 	unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
114 	unsigned select_no_atn:1;
115 	unsigned fix_capacity:1;	/* READ_CAPACITY is too high by 1 */
116 	unsigned retry_hwerror:1;	/* Retry HARDWARE_ERROR */
117 
118 	unsigned int device_blocked;	/* Device returned QUEUE_FULL. */
119 
120 	unsigned int max_device_blocked; /* what device_blocked counts down from  */
121 #define SCSI_DEFAULT_DEVICE_BLOCKED	3
122 
123 	atomic_t iorequest_cnt;
124 	atomic_t iodone_cnt;
125 	atomic_t ioerr_cnt;
126 
127 	int timeout;
128 
129 	struct device		sdev_gendev;
130 	struct class_device	sdev_classdev;
131 
132 	enum scsi_device_state sdev_state;
133 	unsigned long		sdev_data[0];
134 } __attribute__((aligned(sizeof(unsigned long))));
135 #define	to_scsi_device(d)	\
136 	container_of(d, struct scsi_device, sdev_gendev)
137 #define	class_to_sdev(d)	\
138 	container_of(d, struct scsi_device, sdev_classdev)
139 #define transport_class_to_sdev(class_dev) \
140 	to_scsi_device(class_dev->dev)
141 
142 /*
143  * scsi_target: representation of a scsi target, for now, this is only
144  * used for single_lun devices. If no one has active IO to the target,
145  * starget_sdev_user is NULL, else it points to the active sdev.
146  */
147 struct scsi_target {
148 	struct scsi_device	*starget_sdev_user;
149 	struct list_head	siblings;
150 	struct list_head	devices;
151 	struct device		dev;
152 	unsigned int		reap_ref; /* protected by the host lock */
153 	unsigned int		channel;
154 	unsigned int		id; /* target id ... replace
155 				     * scsi_device.id eventually */
156 	unsigned long		create:1; /* signal that it needs to be added */
157 	unsigned long		starget_data[0];
158 } __attribute__((aligned(sizeof(unsigned long))));
159 
160 #define to_scsi_target(d)	container_of(d, struct scsi_target, dev)
161 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
162 {
163 	return to_scsi_target(sdev->sdev_gendev.parent);
164 }
165 #define transport_class_to_starget(class_dev) \
166 	to_scsi_target(class_dev->dev)
167 
168 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
169 		uint, uint, uint, void *hostdata);
170 #define scsi_add_device(host, channel, target, lun) \
171 	__scsi_add_device(host, channel, target, lun, NULL)
172 extern void scsi_remove_device(struct scsi_device *);
173 extern int scsi_device_cancel(struct scsi_device *, int);
174 
175 extern int scsi_device_get(struct scsi_device *);
176 extern void scsi_device_put(struct scsi_device *);
177 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
178 					      uint, uint, uint);
179 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
180 						uint, uint, uint);
181 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
182 							uint);
183 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
184 							  uint);
185 extern void starget_for_each_device(struct scsi_target *, void *,
186 		     void (*fn)(struct scsi_device *, void *));
187 
188 /* only exposed to implement shost_for_each_device */
189 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
190 						  struct scsi_device *);
191 
192 /**
193  * shost_for_each_device  -  iterate over all devices of a host
194  * @sdev:	iterator
195  * @host:	host whiches devices we want to iterate over
196  *
197  * This traverses over each devices of @shost.  The devices have
198  * a reference that must be released by scsi_host_put when breaking
199  * out of the loop.
200  */
201 #define shost_for_each_device(sdev, shost) \
202 	for ((sdev) = __scsi_iterate_devices((shost), NULL); \
203 	     (sdev); \
204 	     (sdev) = __scsi_iterate_devices((shost), (sdev)))
205 
206 /**
207  * __shost_for_each_device  -  iterate over all devices of a host (UNLOCKED)
208  * @sdev:	iterator
209  * @host:	host whiches devices we want to iterate over
210  *
211  * This traverses over each devices of @shost.  It does _not_ take a
212  * reference on the scsi_device, thus it the whole loop must be protected
213  * by shost->host_lock.
214  *
215  * Note:  The only reason why drivers would want to use this is because
216  * they're need to access the device list in irq context.  Otherwise you
217  * really want to use shost_for_each_device instead.
218  */
219 #define __shost_for_each_device(sdev, shost) \
220 	list_for_each_entry((sdev), &((shost)->__devices), siblings)
221 
222 extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
223 extern int scsi_track_queue_full(struct scsi_device *, int);
224 
225 extern int scsi_set_medium_removal(struct scsi_device *, char);
226 
227 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
228 			   unsigned char *buffer, int len, int timeout,
229 			   int retries, struct scsi_mode_data *data);
230 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
231 				int retries);
232 extern int scsi_device_set_state(struct scsi_device *sdev,
233 				 enum scsi_device_state state);
234 extern int scsi_device_quiesce(struct scsi_device *sdev);
235 extern void scsi_device_resume(struct scsi_device *sdev);
236 extern void scsi_target_quiesce(struct scsi_target *);
237 extern void scsi_target_resume(struct scsi_target *);
238 extern void scsi_scan_target(struct device *parent, unsigned int channel,
239 			     unsigned int id, unsigned int lun, int rescan);
240 extern void scsi_target_reap(struct scsi_target *);
241 extern void scsi_target_block(struct device *);
242 extern void scsi_target_unblock(struct device *);
243 extern void scsi_remove_target(struct device *);
244 extern const char *scsi_device_state_name(enum scsi_device_state);
245 extern int scsi_is_sdev_device(const struct device *);
246 extern int scsi_is_target_device(const struct device *);
247 static inline int scsi_device_online(struct scsi_device *sdev)
248 {
249 	return sdev->sdev_state != SDEV_OFFLINE;
250 }
251 
252 /* accessor functions for the SCSI parameters */
253 static inline int scsi_device_sync(struct scsi_device *sdev)
254 {
255 	return sdev->sdtr;
256 }
257 static inline int scsi_device_wide(struct scsi_device *sdev)
258 {
259 	return sdev->wdtr;
260 }
261 static inline int scsi_device_dt(struct scsi_device *sdev)
262 {
263 	return sdev->ppr;
264 }
265 static inline int scsi_device_dt_only(struct scsi_device *sdev)
266 {
267 	if (sdev->inquiry_len < 57)
268 		return 0;
269 	return (sdev->inquiry[56] & 0x0c) == 0x04;
270 }
271 static inline int scsi_device_ius(struct scsi_device *sdev)
272 {
273 	if (sdev->inquiry_len < 57)
274 		return 0;
275 	return sdev->inquiry[56] & 0x01;
276 }
277 static inline int scsi_device_qas(struct scsi_device *sdev)
278 {
279 	if (sdev->inquiry_len < 57)
280 		return 0;
281 	return sdev->inquiry[56] & 0x02;
282 }
283 #endif /* _SCSI_SCSI_DEVICE_H */
284