xref: /freebsd/sys/cam/ctl/ctl_backend.h (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 2003 Silicon Graphics International Corp.
3  * Copyright (c) 2014-2017 Alexander Motin <mav@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions, and the following disclaimer,
11  *    without modification.
12  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
13  *    substantially similar to the "NO WARRANTY" disclaimer below
14  *    ("Disclaimer") and any redistribution must be conditioned upon
15  *    including a substantially similar Disclaimer requirement for further
16  *    binary redistribution.
17  *
18  * NO WARRANTY
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
27  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
28  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGES.
30  *
31  * $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend.h#2 $
32  * $FreeBSD$
33  */
34 /*
35  * CTL backend driver definitions
36  *
37  * Author: Ken Merry <ken@FreeBSD.org>
38  */
39 
40 #ifndef	_CTL_BACKEND_H_
41 #define	_CTL_BACKEND_H_
42 
43 #include <cam/ctl/ctl_ioctl.h>
44 
45 typedef enum {
46 	CTL_LUN_SERSEQ_OFF,
47 	CTL_LUN_SERSEQ_READ,
48 	CTL_LUN_SERSEQ_ON
49 } ctl_lun_serseq;
50 
51 #ifdef _KERNEL
52 
53 #define CTL_BACKEND_DECLARE(name, driver) \
54 	static int name ## _modevent(module_t mod, int type, void *data) \
55 	{ \
56 		switch (type) { \
57 		case MOD_LOAD: \
58 			return (ctl_backend_register( \
59 				(struct ctl_backend_driver *)data)); \
60 			break; \
61 		case MOD_UNLOAD: \
62 			return (ctl_backend_deregister( \
63 				(struct ctl_backend_driver *)data)); \
64 			break; \
65 		default: \
66 			return EOPNOTSUPP; \
67 		} \
68 		return 0; \
69 	} \
70 	static moduledata_t name ## _mod = { \
71 		#name, \
72 		name ## _modevent, \
73 		(void *)&driver \
74 	}; \
75 	DECLARE_MODULE(name, name ## _mod, SI_SUB_CONFIGURE, SI_ORDER_FOURTH); \
76 	MODULE_DEPEND(name, ctl, 1, 1, 1); \
77 	MODULE_DEPEND(name, cam, 1, 1, 1)
78 
79 
80 typedef enum {
81 	CTL_LUN_CONFIG_OK,
82 	CTL_LUN_CONFIG_FAILURE
83 } ctl_lun_config_status;
84 
85 typedef void (*be_callback_t)(void *be_lun);
86 typedef void (*be_lun_config_t)(void *be_lun,
87 				ctl_lun_config_status status);
88 
89 /*
90  * The lun_type field is the SCSI device type of this particular LUN.  In
91  * general, this should be T_DIRECT, although backends will want to create
92  * a processor LUN, typically at LUN 0.  See scsi_all.h for the defines for
93  * the various SCSI device types.
94  *
95  * The flags are described above.
96  *
97  * The be_lun field is the backend driver's own context that will get
98  * passsed back so that it can tell which LUN CTL is referencing.
99  *
100  * maxlba is the maximum accessible LBA on the LUN.  Note that this is
101  * different from the capacity of the array.  capacity = maxlba + 1
102  *
103  * blocksize is the size, in bytes, of each LBA on the LUN.  In general
104  * this should be 512.  In theory CTL should be able to handle other block
105  * sizes.  Host application software may not deal with it very well, though.
106  *
107  * pblockexp is the log2() of number of LBAs on the LUN per physical sector.
108  *
109  * pblockoff is the lowest LBA on the LUN aligned to physical sector.
110  *
111  * ublockexp is the log2() of number of LBAs on the LUN per UNMAP block.
112  *
113  * ublockoff is the lowest LBA on the LUN aligned to UNMAP block.
114  *
115  * atomicblock is the number of blocks that can be written atomically.
116  *
117  * opttxferlen is the number of blocks that can be written in one operation.
118  *
119  * req_lun_id is the requested LUN ID.  CTL only pays attention to this
120  * field if the CTL_LUN_FLAG_ID_REQ flag is set.  If the requested LUN ID is
121  * not available, the LUN addition will fail.  If a particular LUN ID isn't
122  * requested, the first available LUN ID will be allocated.
123  *
124  * serial_num is the device serial number returned in the SCSI INQUIRY VPD
125  * page 0x80.  This should be a unique, per-shelf value.  The data inside
126  * this field should be ASCII only, left aligned, and any unused space
127  * should be padded out with ASCII spaces.  This field should NOT be NULL
128  * terminated.
129  *
130  * device_id is the T10 device identifier returned in the SCSI INQUIRY VPD
131  * page 0x83.  This should be a unique, per-LUN value.  The data inside
132  * this field should be ASCII only, left aligned, and any unused space
133  * should be padded with ASCII spaces.  This field should NOT be NULL
134  * terminated.
135  *
136  * The lun_shutdown() method is the callback for the ctl_invalidate_lun()
137  * call.  It is called when all outstanding I/O for that LUN has been
138  * completed and CTL has deleted the resources for that LUN.  When the CTL
139  * backend gets this call, it can safely free its per-LUN resources.
140  *
141  * The lun_config_status() method is the callback for the ctl_add_lun()
142  * call.  It is called when the LUN is successfully added, or when LUN
143  * addition fails.  If the LUN is successfully added, the backend may call
144  * the ctl_enable_lun() method to enable the LUN.
145  *
146  * The be field is a pointer to the ctl_backend_driver structure, which
147  * contains the backend methods to be called by CTL.
148  *
149  * The ctl_lun field is for CTL internal use only, and should not be used
150  * by the backend.
151  *
152  * The links field is for CTL internal use only, and should not be used by
153  * the backend.
154  */
155 struct ctl_be_lun {
156 	uint8_t			lun_type;	/* passed to CTL */
157 	ctl_backend_lun_flags	flags;		/* passed to CTL */
158 	ctl_lun_serseq		serseq;		/* passed to CTL */
159 	void			*be_lun;	/* passed to CTL */
160 	uint64_t		maxlba;		/* passed to CTL */
161 	uint32_t		blocksize;	/* passed to CTL */
162 	uint16_t		pblockexp;	/* passed to CTL */
163 	uint16_t		pblockoff;	/* passed to CTL */
164 	uint16_t		ublockexp;	/* passed to CTL */
165 	uint16_t		ublockoff;	/* passed to CTL */
166 	uint32_t		atomicblock;	/* passed to CTL */
167 	uint32_t		opttxferlen;	/* passed to CTL */
168 	uint32_t		req_lun_id;	/* passed to CTL */
169 	uint32_t		lun_id;		/* returned from CTL */
170 	uint8_t			serial_num[CTL_SN_LEN];	 /* passed to CTL */
171 	uint8_t			device_id[CTL_DEVID_LEN];/* passed to CTL */
172 	be_callback_t		lun_shutdown;	/* passed to CTL */
173 	be_lun_config_t		lun_config_status; /* passed to CTL */
174 	struct ctl_backend_driver *be;		/* passed to CTL */
175 	void			*ctl_lun;	/* used by CTL */
176 	ctl_options_t		options;	/* passed to CTL */
177 	STAILQ_ENTRY(ctl_be_lun) links;		/* used by CTL */
178 };
179 
180 typedef enum {
181 	CTL_BE_FLAG_NONE	= 0x00,	/* no flags */
182 	CTL_BE_FLAG_HAS_CONFIG	= 0x01,	/* can do config reads, writes */
183 } ctl_backend_flags;
184 
185 typedef int (*be_init_t)(void);
186 typedef int (*be_shutdown_t)(void);
187 typedef int (*be_func_t)(union ctl_io *io);
188 typedef void (*be_vfunc_t)(union ctl_io *io);
189 typedef int (*be_ioctl_t)(struct cdev *dev, u_long cmd, caddr_t addr, int flag,
190 			  struct thread *td);
191 typedef int (*be_luninfo_t)(void *be_lun, struct sbuf *sb);
192 typedef uint64_t (*be_lunattr_t)(void *be_lun, const char *attrname);
193 
194 struct ctl_backend_driver {
195 	char		  name[CTL_BE_NAME_LEN]; /* passed to CTL */
196 	ctl_backend_flags flags;	         /* passed to CTL */
197 	be_init_t	  init;			 /* passed to CTL */
198 	be_shutdown_t	  shutdown;		 /* passed to CTL */
199 	be_func_t	  data_submit;		 /* passed to CTL */
200 	be_func_t	  data_move_done;	 /* passed to CTL */
201 	be_func_t	  config_read;		 /* passed to CTL */
202 	be_func_t	  config_write;		 /* passed to CTL */
203 	be_ioctl_t	  ioctl;		 /* passed to CTL */
204 	be_luninfo_t	  lun_info;		 /* passed to CTL */
205 	be_lunattr_t	  lun_attr;		 /* passed to CTL */
206 #ifdef CS_BE_CONFIG_MOVE_DONE_IS_NOT_USED
207 	be_func_t	  config_move_done;	 /* passed to backend */
208 #endif
209 #if 0
210 	be_vfunc_t	  config_write_done;	 /* passed to backend */
211 #endif
212 	u_int		  num_luns;		 /* used by CTL */
213 	STAILQ_ENTRY(ctl_backend_driver) links;	 /* used by CTL */
214 };
215 
216 int ctl_backend_register(struct ctl_backend_driver *be);
217 int ctl_backend_deregister(struct ctl_backend_driver *be);
218 struct ctl_backend_driver *ctl_backend_find(char *backend_name);
219 
220 /*
221  * To add a LUN, first call ctl_add_lun().  You will get the lun_config_status()
222  * callback when the LUN addition has either succeeded or failed.
223  *
224  * Once you get that callback, you can then call ctl_enable_lun() to enable
225  * the LUN.
226  */
227 int ctl_add_lun(struct ctl_be_lun *be_lun);
228 int ctl_enable_lun(struct ctl_be_lun *be_lun);
229 
230 /*
231  * To delete a LUN, first call ctl_disable_lun(), then
232  * ctl_invalidate_lun().  You will get the lun_shutdown() callback when all
233  * I/O to the LUN has completed and the LUN has been deleted.
234  */
235 int ctl_disable_lun(struct ctl_be_lun *be_lun);
236 int ctl_invalidate_lun(struct ctl_be_lun *be_lun);
237 
238 /*
239  * To start a LUN (transition from powered off to powered on state) call
240  * ctl_start_lun().  To stop a LUN (transition from powered on to powered
241  * off state) call ctl_stop_lun().
242  */
243 int ctl_start_lun(struct ctl_be_lun *be_lun);
244 int ctl_stop_lun(struct ctl_be_lun *be_lun);
245 
246 /*
247  * Methods to notify about media and tray status changes.
248  */
249 int ctl_lun_no_media(struct ctl_be_lun *be_lun);
250 int ctl_lun_has_media(struct ctl_be_lun *be_lun);
251 int ctl_lun_ejected(struct ctl_be_lun *be_lun);
252 
253 /*
254  * Called on LUN HA role change.
255  */
256 int ctl_lun_primary(struct ctl_be_lun *be_lun);
257 int ctl_lun_secondary(struct ctl_be_lun *be_lun);
258 
259 /*
260  * Let the backend notify the initiators about changes.
261  */
262 void ctl_lun_capacity_changed(struct ctl_be_lun *be_lun);
263 
264 #endif /* _KERNEL */
265 #endif /* _CTL_BACKEND_H_ */
266 
267 /*
268  * vim: ts=8
269  */
270