xref: /dragonfly/sys/dev/raid/vinum/request.h (revision 2c3b1d1b)
1 /*-
2  * Copyright (c) 1997, 1998
3  *	Nan Yang Computer Services Limited.  All rights reserved.
4  *
5  *  This software is distributed under the so-called ``Berkeley
6  *  License'':
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Nan Yang Computer
19  *      Services Limited.
20  * 4. Neither the name of the Company nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * This software is provided ``as is'', and any express or implied
25  * warranties, including, but not limited to, the implied warranties of
26  * merchantability and fitness for a particular purpose are disclaimed.
27  * In no event shall the company or contributors be liable for any
28  * direct, indirect, incidental, special, exemplary, or consequential
29  * damages (including, but not limited to, procurement of substitute
30  * goods or services; loss of use, data, or profits; or business
31  * interruption) however caused and on any theory of liability, whether
32  * in contract, strict liability, or tort (including negligence or
33  * otherwise) arising in any way out of the use of this software, even if
34  * advised of the possibility of such damage.
35  */
36 
37 /* Information needed to set up a transfer */
38 
39 enum xferinfo {
40 	XFR_NORMAL_READ = 1,
41 	XFR_NORMAL_WRITE = 2,		/* write request in normal mode */
42 	XFR_RECOVERY_READ = 4,
43 	XFR_DEGRADED_WRITE = 8,
44 	XFR_PARITYLESS_WRITE = 0x10,
45 	XFR_NO_PARITY_STRIPE = 0x20,	/* parity stripe is not available */
46 	XFR_DATA_BLOCK = 0x40,		/* data block in request */
47 	XFR_PARITY_BLOCK = 0x80,	/* parity block in request */
48 	XFR_BAD_SUBDISK = 0x100,	/* this subdisk is dead */
49 	XFR_MALLOCED = 0x200,		/* this buffer is malloced */
50 #ifdef VINUMDEBUG
51 	XFR_PHASE2 = 0x800,		/* debug only: 2nd phase write */
52 #endif
53 	XFR_REVIVECONFLICT = 0x1000,	/* possible conflict with a revive */
54 	XFR_BUFLOCKED = 0x2000,		/* BUF_LOCK performed on this buffer */
55 
56 	/*
57 	 * operations that need a parity block
58 	 */
59 	XFR_PARITYOP = (XFR_NORMAL_WRITE | XFR_RECOVERY_READ |
60 			XFR_DEGRADED_WRITE),
61 
62 	/*
63 	 * operations that use the group parameters
64 	 */
65 	XFR_GROUPOP = (XFR_DEGRADED_WRITE | XFR_RECOVERY_READ),
66 
67 	/*
68 	 * operations that that use the data parameters
69 	 */
70 	XFR_DATAOP = (XFR_NORMAL_READ | XFR_NORMAL_WRITE |
71 		      XFR_PARITYLESS_WRITE),
72 
73 	/*
74 	 * operations requiring read before write
75 	 */
76 	XFR_RBW = (XFR_NORMAL_WRITE | XFR_DEGRADED_WRITE),
77 
78 	/*
79 	 * operations that need a malloced buffer
80 	 */
81 	XFR_NEEDS_MALLOC = (XFR_NORMAL_WRITE | XFR_RECOVERY_READ |
82 			    XFR_DEGRADED_WRITE)
83 };
84 
85 /*
86  * Describe one low-level request, part of a
87  * high-level request.  This is an extended
88  * struct buf buffer, and the first element
89  * *must* be a struct buf.  We pass this
90  * structure to the I/O routines instead of a
91  * struct buf in order to be able to locate the
92  * high-level request when it completes.
93  *
94  * All offsets and lengths are in sectors.
95  */
96 struct rqelement {
97 	struct buf b;			/* buf structure */
98 	struct rqgroup *rqg;		/* pointer to our group */
99 
100 	vinum_off_t sdoffset;		/* offset in subdisk */
101 	int useroffset;			/* offset of data in user buffer */
102 
103 	/*
104 	 * dataoffset and datalen refer to "individual" data
105 	 * transfers which involve only this drive (normal read,
106 	 * parityless write) and also degraded write.
107 	 *
108 	 * groupoffset and grouplen refer to the other "group"
109 	 * operations (normal write, recovery read) which involve
110 	 * more than one drive.  Both the offsets are relative to
111 	 * the start of the local buffer.
112 	 */
113 	int dataoffset;			/* offset of the normal data */
114 	int groupoffset;		/* offset of group data */
115 	short datalen;			/* length of normal data (sectors) */
116 	short grouplen;			/* length of group data (sectors) */
117 	short buflen;			/* total buffer length to allocate */
118 	short flags;			/* really enum xferinfo (see above) */
119 
120 	/*
121 	 * Ways to find other components
122 	 */
123 	short sdno;			/* subdisk number */
124 	short driveno;			/* drive number */
125 };
126 
127 /*
128  * A group of requests built to satisfy an I/O
129  * transfer on a single plex.
130  */
131 struct rqgroup {
132 	struct rqgroup *next;		/* pointer to next group */
133 	struct request *rq;		/* pointer to the request */
134 	short count;			/* number of requests in this group */
135 	short active;			/* and number active */
136 	short plexno;			/* index of plex */
137 	int badsdno;			/* index of bad subdisk or -1 */
138 	enum xferinfo flags;		/* description of transfer */
139 	struct rangelock *lock;		/* lock for this transfer */
140 	vinum_off_t lockbase;		/* and lock address */
141 	struct rqelement rqe[0];	/* and the elements of this request */
142 };
143 
144 /*
145  * Describe one high-level request and the
146  * work we have to do to satisfy it.
147  */
148 struct request {
149 	struct bio *bio;		/* pointer to the high-level request */
150 	enum xferinfo flags;
151 	union {
152 	    int volno;			/* volume index */
153 	    int plexno;			/* or plex index */
154 	} volplex;
155 	int error;			/* current error indication */
156 	int sdno;			/* reviving subdisk	*/
157 					/* (XFR_REVIVECONFLICT) */
158 	short isplex;			/* set if this is a plex request */
159 	short active;			/* number of subrequests still active */
160 	struct rqgroup *rqg;		/* ptr to the first group of requests */
161 	struct rqgroup *lrqg;		/* and to the last group of requests */
162 	struct request *next;		/* link of waiting requests */
163 };
164 
165 /*
166  * Extended buffer header for subdisk I/O.  Includes
167  * a pointer to the user I/O request.
168  */
169 struct sdbuf {
170 	struct buf b;			/* our buffer */
171 	struct bio *bio;		/* and pointer to parent */
172 	short driveno;			/* drive index */
173 	short sdno;			/* and subdisk index */
174 };
175 
176 /*
177  * Values returned by rqe and friends.  Be careful
178  * with these: they are in order of increasing
179  * seriousness.  Some routines check for
180  * > REQUEST_RECOVERED to indicate a failed request. XXX
181  */
182 enum requeststatus {
183 	REQUEST_OK,		/* request built OK */
184 	REQUEST_RECOVERED,	/* request OK, but involves RAID5 recovery */
185 	REQUEST_DEGRADED,	/* parts of request failed */
186 	REQUEST_EOF,		/* parts of request failed: outside plex */
187 	REQUEST_DOWN,		/* all of request failed: subdisk(s) down */
188 	REQUEST_ENOMEM		/* all of request failed: ran out of memory */
189 };
190 
191 #ifdef VINUMDEBUG
192 
193 /*
194  * Trace entry for request info (DEBUG_LASTREQS)
195  */
196 enum rqinfo_type {
197 	loginfo_unused,		/* never been used */
198 	loginfo_user_bp,	/* this is the bp when strategy is called */
199 	loginfo_user_bpl,	/* and this is the bp at launch time */
200 	loginfo_rqe,		/* user RQE */
201 	loginfo_iodone,		/* iodone */
202 	loginfo_raid5_data,	/* write RAID-5 data block */
203 	loginfo_raid5_parity,	/* write RAID-5 parity block */
204 	loginfo_sdio,		/* subdisk I/O */
205 	loginfo_sdiol,		/* subdisk I/O launch */
206 	loginfo_sdiodone,	/* subdisk iodone */
207 	loginfo_lockwait,	/* wait for range lock */
208 	loginfo_lock,		/* lock range */
209 	loginfo_unlock,		/* unlock range */
210 };
211 
212 /*
213  * Info to pass to logrq
214  */
215 union rqinfou {
216 	struct bio *bio;
217 	struct rqelement *rqe;		/* addr of request, for correlation */
218 	struct rangelock *lockinfo;
219 };
220 
221 struct rqinfo {
222 	enum rqinfo_type type;		/* kind of event */
223 	struct timeval timestamp;	/* time it happened */
224 	struct bio *bio;		/* point to user buffer */
225 	int devmajor;			/* major and minor device info */
226 	int devminor;
227 	union {
228 		struct buf b;		/* yup, the *whole* buffer header */
229 		struct bio bio;
230 		struct rqelement rqe;	/* and the whole rqe */
231 		struct rangelock lockinfo;
232 	} info;
233 };
234 
235 #define RQINFO_SIZE 128		/* number of info slots in buffer */
236 
237 void logrq(enum rqinfo_type type, union rqinfou info, struct bio *ubio);
238 
239 #endif
240 
241 /* Structures for the daemon */
242 
243 /*
244  * Types of request to the daemon
245  */
246 enum daemonrq {
247 	daemonrq_none,		/* dummy to catch bugs */
248 	daemonrq_ioerror,	/* error occurred on I/O */
249 	daemonrq_saveconfig,	/* save configuration */
250 	daemonrq_return,	/* return to userland */
251 	daemonrq_ping,		/* show sign of life */
252 	daemonrq_init,		/* initialize a plex */
253 	daemonrq_revive,	/* revive a subdisk */
254 	daemonrq_closedrive,	/* close a drive */
255 };
256 
257 /*
258  * Info field for daemon requests and the request information
259  */
260 union daemoninfo {
261 	struct request *rq;	/* for daemonrq_ioerror */
262 	struct sd *sd;		/* for daemonrq_revive */
263 	struct plex *plex;	/* for daemonrq_init */
264 	struct drive *drive;	/* for daemonrq_closedrive */
265 	int nothing;		/* for passing NULL */
266 };
267 
268 struct daemonq {
269 	struct daemonq *next;	/* pointer to next element in queue */
270 	enum daemonrq type;	/* type of request */
271 	int privateinuse;	/* private element, being used */
272 	union daemoninfo info;	/* and the request information */
273 };
274 
275 void queue_daemon_request(enum daemonrq type, union daemoninfo info);
276 
277 extern int daemon_options;
278 
279 enum daemon_option {
280 	daemon_verbose = 1,	/* talk about what we're doing */
281 	daemon_stopped = 2,
282 	daemon_noupdate = 4,	/* don't update the disk config, for recovery */
283 };
284 
285 void freerq(struct request *rq);
286 void unlockrange(int plexno, struct rangelock *);
287