xref: /freebsd/sys/cam/ctl/ctl_backend.h (revision a831d7d1c538b93ffec095657d9a6e6e778db195)
1 /*-
2  * Copyright (c) 2003 Silicon Graphics International Corp.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions, and the following disclaimer,
10  *    without modification.
11  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12  *    substantially similar to the "NO WARRANTY" disclaimer below
13  *    ("Disclaimer") and any redistribution must be conditioned upon
14  *    including a substantially similar Disclaimer requirement for further
15  *    binary redistribution.
16  *
17  * NO WARRANTY
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGES.
29  *
30  * $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend.h#2 $
31  * $FreeBSD$
32  */
33 /*
34  * CTL backend driver definitions
35  *
36  * Author: Ken Merry <ken@FreeBSD.org>
37  */
38 
39 #ifndef	_CTL_BACKEND_H_
40 #define	_CTL_BACKEND_H_
41 
42 /*
43  * XXX KDM move this to another header file?
44  */
45 #define	CTL_BE_NAME_LEN		32
46 
47 /*
48  * The ID_REQ flag is used to say that the caller has requested a
49  * particular LUN ID in the req_lun_id field.  If we cannot allocate that
50  * LUN ID, the ctl_add_lun() call will fail.
51  *
52  * The POWERED_OFF flag tells us that the LUN should default to the powered
53  * off state.  It will return 0x04,0x02 until it is powered up.  ("Logical
54  * unit not ready, initializing command required.")
55  *
56  * The INOPERABLE flag tells us that this LUN is not operable for whatever
57  * reason.  This means that user data may have been (or has been?) lost.
58  * We will return 0x31,0x00 ("Medium format corrupted") until the host
59  * issues a FORMAT UNIT command to clear the error.
60  *
61  * The PRIMARY flag tells us that this LUN is registered as a Primary LUN
62  * which is accessible via the Master shelf controller in an HA. This flag
63  * being set indicates a Primary LUN. This flag being reset represents a
64  * Secondary LUN controlled by the Secondary controller in an HA
65  * configuration. Flag is applicable at this time to T_DIRECT types.
66  *
67  * The SERIAL_NUM flag tells us that the serial_num field is filled in and
68  * valid for use in SCSI INQUIRY VPD page 0x80.
69  *
70  * The DEVID flag tells us that the device_id field is filled in and
71  * valid for use in SCSI INQUIRY VPD page 0x83.
72  *
73  * The DEV_TYPE flag tells us that the device_type field is filled in.
74  *
75  * The UNMAP flag tells us that this LUN supports UNMAP.
76  *
77  * The OFFLINE flag tells us that this LUN can not access backing store.
78  */
79 typedef enum {
80 	CTL_LUN_FLAG_ID_REQ		= 0x01,
81 	CTL_LUN_FLAG_POWERED_OFF	= 0x02,
82 	CTL_LUN_FLAG_INOPERABLE		= 0x04,
83 	CTL_LUN_FLAG_PRIMARY		= 0x08,
84 	CTL_LUN_FLAG_SERIAL_NUM		= 0x10,
85 	CTL_LUN_FLAG_DEVID		= 0x20,
86 	CTL_LUN_FLAG_DEV_TYPE		= 0x40,
87 	CTL_LUN_FLAG_UNMAP		= 0x80,
88 	CTL_LUN_FLAG_OFFLINE		= 0x100,
89 	CTL_LUN_FLAG_SERSEQ_READ	= 0x200
90 } ctl_backend_lun_flags;
91 
92 #ifdef _KERNEL
93 
94 #define CTL_BACKEND_DECLARE(name, driver) \
95 	static int name ## _modevent(module_t mod, int type, void *data) \
96 	{ \
97 		switch (type) { \
98 		case MOD_LOAD: \
99 			ctl_backend_register( \
100 				(struct ctl_backend_driver *)data); \
101 			break; \
102 		case MOD_UNLOAD: \
103 			printf(#name " module unload - not possible for this module type\n"); \
104 			return EINVAL; \
105 		default: \
106 			return EOPNOTSUPP; \
107 		} \
108 		return 0; \
109 	} \
110 	static moduledata_t name ## _mod = { \
111 		#name, \
112 		name ## _modevent, \
113 		(void *)&driver \
114 	}; \
115 	DECLARE_MODULE(name, name ## _mod, SI_SUB_CONFIGURE, SI_ORDER_FOURTH); \
116 	MODULE_DEPEND(name, ctl, 1, 1, 1); \
117 	MODULE_DEPEND(name, cam, 1, 1, 1)
118 
119 
120 typedef enum {
121 	CTL_LUN_CONFIG_OK,
122 	CTL_LUN_CONFIG_FAILURE
123 } ctl_lun_config_status;
124 
125 typedef void (*be_callback_t)(void *be_lun);
126 typedef void (*be_lun_config_t)(void *be_lun,
127 				ctl_lun_config_status status);
128 
129 /*
130  * The lun_type field is the SCSI device type of this particular LUN.  In
131  * general, this should be T_DIRECT, although backends will want to create
132  * a processor LUN, typically at LUN 0.  See scsi_all.h for the defines for
133  * the various SCSI device types.
134  *
135  * The flags are described above.
136  *
137  * The be_lun field is the backend driver's own context that will get
138  * passsed back so that it can tell which LUN CTL is referencing.
139  *
140  * maxlba is the maximum accessible LBA on the LUN.  Note that this is
141  * different from the capacity of the array.  capacity = maxlba + 1
142  *
143  * blocksize is the size, in bytes, of each LBA on the LUN.  In general
144  * this should be 512.  In theory CTL should be able to handle other block
145  * sizes.  Host application software may not deal with it very well, though.
146  *
147  * pblockexp is the log2() of number of LBAs on the LUN per physical sector.
148  *
149  * pblockoff is the lowest LBA on the LUN aligned to physical sector.
150  *
151  * ublockexp is the log2() of number of LBAs on the LUN per UNMAP block.
152  *
153  * ublockoff is the lowest LBA on the LUN aligned to UNMAP block.
154  *
155  * atomicblock is the number of blocks that can be written atomically.
156  *
157  * opttxferlen is the number of blocks that can be written in one operation.
158  *
159  * req_lun_id is the requested LUN ID.  CTL only pays attention to this
160  * field if the CTL_LUN_FLAG_ID_REQ flag is set.  If the requested LUN ID is
161  * not available, the LUN addition will fail.  If a particular LUN ID isn't
162  * requested, the first available LUN ID will be allocated.
163  *
164  * serial_num is the device serial number returned in the SCSI INQUIRY VPD
165  * page 0x80.  This should be a unique, per-shelf value.  The data inside
166  * this field should be ASCII only, left aligned, and any unused space
167  * should be padded out with ASCII spaces.  This field should NOT be NULL
168  * terminated.
169  *
170  * device_id is the T10 device identifier returned in the SCSI INQUIRY VPD
171  * page 0x83.  This should be a unique, per-LUN value.  The data inside
172  * this field should be ASCII only, left aligned, and any unused space
173  * should be padded with ASCII spaces.  This field should NOT be NULL
174  * terminated.
175  *
176  * The lun_shutdown() method is the callback for the ctl_invalidate_lun()
177  * call.  It is called when all outstanding I/O for that LUN has been
178  * completed and CTL has deleted the resources for that LUN.  When the CTL
179  * backend gets this call, it can safely free its per-LUN resources.
180  *
181  * The lun_config_status() method is the callback for the ctl_add_lun()
182  * call.  It is called when the LUN is successfully added, or when LUN
183  * addition fails.  If the LUN is successfully added, the backend may call
184  * the ctl_enable_lun() method to enable the LUN.
185  *
186  * The be field is a pointer to the ctl_backend_driver structure, which
187  * contains the backend methods to be called by CTL.
188  *
189  * The ctl_lun field is for CTL internal use only, and should not be used
190  * by the backend.
191  *
192  * The links field is for CTL internal use only, and should not be used by
193  * the backend.
194  */
195 struct ctl_be_lun {
196 	uint8_t			lun_type;	/* passed to CTL */
197 	ctl_backend_lun_flags	flags;		/* passed to CTL */
198 	void			*be_lun;	/* passed to CTL */
199 	uint64_t		maxlba;		/* passed to CTL */
200 	uint32_t		blocksize;	/* passed to CTL */
201 	uint16_t		pblockexp;	/* passed to CTL */
202 	uint16_t		pblockoff;	/* passed to CTL */
203 	uint16_t		ublockexp;	/* passed to CTL */
204 	uint16_t		ublockoff;	/* passed to CTL */
205 	uint32_t		atomicblock;	/* passed to CTL */
206 	uint32_t		opttxferlen;	/* passed to CTL */
207 	uint32_t		req_lun_id;	/* passed to CTL */
208 	uint32_t		lun_id;		/* returned from CTL */
209 	uint8_t			serial_num[CTL_SN_LEN];	 /* passed to CTL */
210 	uint8_t			device_id[CTL_DEVID_LEN];/* passed to CTL */
211 	be_callback_t		lun_shutdown;	/* passed to CTL */
212 	be_lun_config_t		lun_config_status; /* passed to CTL */
213 	struct ctl_backend_driver *be;		/* passed to CTL */
214 	void			*ctl_lun;	/* used by CTL */
215 	ctl_options_t		options;	/* passed to CTL */
216 	STAILQ_ENTRY(ctl_be_lun) links;		/* used by CTL */
217 };
218 
219 typedef enum {
220 	CTL_BE_FLAG_NONE	= 0x00,	/* no flags */
221 	CTL_BE_FLAG_HAS_CONFIG	= 0x01,	/* can do config reads, writes */
222 	CTL_BE_FLAG_INTERNAL	= 0x02	/* don't inc mod refcount */
223 } ctl_backend_flags;
224 
225 typedef int (*be_init_t)(void);
226 typedef int (*be_func_t)(union ctl_io *io);
227 typedef void (*be_vfunc_t)(union ctl_io *io);
228 typedef int (*be_ioctl_t)(struct cdev *dev, u_long cmd, caddr_t addr, int flag,
229 			  struct thread *td);
230 typedef int (*be_luninfo_t)(void *be_lun, struct sbuf *sb);
231 typedef uint64_t (*be_lunattr_t)(void *be_lun, const char *attrname);
232 
233 struct ctl_backend_driver {
234 	char		  name[CTL_BE_NAME_LEN]; /* passed to CTL */
235 	ctl_backend_flags flags;	         /* passed to CTL */
236 	be_init_t	  init;			 /* passed to CTL */
237 	be_func_t	  data_submit;		 /* passed to CTL */
238 	be_func_t	  data_move_done;	 /* passed to CTL */
239 	be_func_t	  config_read;		 /* passed to CTL */
240 	be_func_t	  config_write;		 /* passed to CTL */
241 	be_ioctl_t	  ioctl;		 /* passed to CTL */
242 	be_luninfo_t	  lun_info;		 /* passed to CTL */
243 	be_lunattr_t	  lun_attr;		 /* passed to CTL */
244 #ifdef CS_BE_CONFIG_MOVE_DONE_IS_NOT_USED
245 	be_func_t	  config_move_done;	 /* passed to backend */
246 #endif
247 #if 0
248 	be_vfunc_t	  config_write_done;	 /* passed to backend */
249 #endif
250 	u_int		  num_luns;		 /* used by CTL */
251 	STAILQ_ENTRY(ctl_backend_driver) links;	 /* used by CTL */
252 };
253 
254 int ctl_backend_register(struct ctl_backend_driver *be);
255 int ctl_backend_deregister(struct ctl_backend_driver *be);
256 struct ctl_backend_driver *ctl_backend_find(char *backend_name);
257 
258 /*
259  * To add a LUN, first call ctl_add_lun().  You will get the lun_config_status()
260  * callback when the LUN addition has either succeeded or failed.
261  *
262  * Once you get that callback, you can then call ctl_enable_lun() to enable
263  * the LUN.
264  */
265 int ctl_add_lun(struct ctl_be_lun *be_lun);
266 int ctl_enable_lun(struct ctl_be_lun *be_lun);
267 
268 /*
269  * To delete a LUN, first call ctl_disable_lun(), then
270  * ctl_invalidate_lun().  You will get the lun_shutdown() callback when all
271  * I/O to the LUN has completed and the LUN has been deleted.
272  */
273 int ctl_disable_lun(struct ctl_be_lun *be_lun);
274 int ctl_invalidate_lun(struct ctl_be_lun *be_lun);
275 
276 /*
277  * To start a LUN (transition from powered off to powered on state) call
278  * ctl_start_lun().  To stop a LUN (transition from powered on to powered
279  * off state) call ctl_stop_lun().
280  */
281 int ctl_start_lun(struct ctl_be_lun *be_lun);
282 int ctl_stop_lun(struct ctl_be_lun *be_lun);
283 
284 /*
285  * If a LUN is inoperable, call ctl_lun_inoperable().  Generally the LUN
286  * will become operable once again when the user issues the SCSI FORMAT UNIT
287  * command.  (CTL will automatically clear the inoperable flag.)  If we
288  * need to re-enable the LUN, we can call ctl_lun_operable() to enable it
289  * without a SCSI command.
290  */
291 int ctl_lun_inoperable(struct ctl_be_lun *be_lun);
292 int ctl_lun_operable(struct ctl_be_lun *be_lun);
293 
294 /*
295  * To take a LUN offline, call ctl_lun_offline().  Generally the LUN will
296  * be online again once the user sends a SCSI START STOP UNIT command with
297  * the start and on/offline bits set.  The backend can bring the LUN back
298  * online via the ctl_lun_online() function, if necessary.
299  */
300 int ctl_lun_offline(struct ctl_be_lun *be_lun);
301 int ctl_lun_online(struct ctl_be_lun *be_lun);
302 
303 /*
304  * Let the backend notify the initiator about changed capacity.
305  */
306 void ctl_lun_capacity_changed(struct ctl_be_lun *be_lun);
307 
308 #endif /* _KERNEL */
309 #endif /* _CTL_BACKEND_H_ */
310 
311 /*
312  * vim: ts=8
313  */
314