mdadm-0.7.1
[thirdparty/mdadm.git] / Create.c
1 /*
2 * mdadm - manage Linux "md" devices aka RAID arrays.
3 *
4 * Copyright (C) 2001-2002 Neil Brown <neilb@cse.unsw.edu.au>
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 * Author: Neil Brown
22 * Email: <neilb@cse.unsw.edu.au>
23 * Paper: Neil Brown
24 * School of Computer Science and Engineering
25 * The University of New South Wales
26 * Sydney, 2052
27 * Australia
28 */
29
30 #include "mdadm.h"
31 #include "md_u.h"
32 #include "md_p.h"
33
34 int Create(char *mddev, int mdfd,
35 int chunk, int level, int layout, int size, int raiddisks, int sparedisks,
36 int subdevs, mddev_dev_t devlist,
37 int runstop, int verbose, int force)
38 {
39 /*
40 * Create a new raid array.
41 *
42 * First check that necessary details are available
43 * (i.e. level, raid-disks)
44 *
45 * Then check each disk to see what might be on it
46 * and report anything interesting.
47 *
48 * If anything looks odd, and runstop not set,
49 * abort.
50 *
51 * SET_ARRAY_INFO and ADD_NEW_DISK, and
52 * if runstop==run, or raiddisks diskswere used,
53 * RUN_ARRAY
54 */
55 int minsize, maxsize;
56 char *mindisc = NULL;
57 char *maxdisc = NULL;
58 int i;
59 mddev_dev_t dv;
60 int fail=0, warn=0;
61 struct stat stb;
62 int first_missing = MD_SB_DISKS*2;
63 int missing_disks = 0;
64 int insert_point = MD_SB_DISKS*2; /* where to insert a missing drive */
65
66 mdu_array_info_t array;
67
68
69 if (md_get_version(mdfd) < 9000) {
70 fprintf(stderr, Name ": Create requires md driver verison 0.90.0 or later\n");
71 return 1;
72 }
73 if (level == -10) {
74 fprintf(stderr,
75 Name ": a RAID level is needed to create an array.\n");
76 return 1;
77 }
78 if (raiddisks < 1) {
79 fprintf(stderr,
80 Name ": a number of --raid-disks must be given to create an array\n");
81 return 1;
82 }
83 if (raiddisks < 2 && level >= 4) {
84 fprintf(stderr,
85 Name ": atleast 2 raid-disks needed for level 4 or 5\n");
86 return 1;
87 }
88 if (raiddisks+sparedisks > MD_SB_DISKS) {
89 fprintf(stderr,
90 Name ": too many discs requested: %d+%d > %d\n",
91 raiddisks, sparedisks, MD_SB_DISKS);
92 return 1;
93 }
94 if (subdevs > raiddisks+sparedisks) {
95 fprintf(stderr, Name ": You have listed more disks (%d) than are in the array(%d)!\n", subdevs, raiddisks+sparedisks);
96 return 1;
97 }
98 if (subdevs < raiddisks+sparedisks) {
99 fprintf(stderr, Name ": You haven't given enough devices (real or missing) to create this array\n");
100 return 1;
101 }
102
103 /* now set some defaults */
104 if (layout == -1)
105 switch(level) {
106 default: /* no layout */
107 layout = 0;
108 break;
109 case 5:
110 layout = map_name(r5layout, "default");
111 if (verbose)
112 fprintf(stderr,
113 Name ": layout defaults to %s\n", map_num(r5layout, layout));
114 break;
115 }
116
117 if (chunk == 0) {
118 chunk = 64;
119 if (verbose)
120 fprintf(stderr, Name ": chunk size defaults to 64K\n");
121 }
122
123 /* now look at the subdevs */
124 array.active_disks = 0;
125 array.working_disks = 0;
126 for (dv=devlist; dv; dv=dv->next) {
127 char *dname = dv->devname;
128 int dsize, freesize;
129 int fd;
130 if (strcasecmp(dname, "missing")==0) {
131 if (first_missing > i)
132 first_missing = i;
133 missing_disks ++;
134 continue;
135 }
136 array.working_disks++;
137 if (i < raiddisks)
138 array.active_disks++;
139 fd = open(dname, O_RDONLY, 0);
140 if (fd <0 ) {
141 fprintf(stderr, Name ": Cannot open %s: %s\n",
142 dname, strerror(errno));
143 fail=1;
144 continue;
145 }
146 if (ioctl(fd, BLKGETSIZE, &dsize)) {
147 fprintf(stderr, Name ": Cannot get size of %s: %s\n",
148 dname, strerror(errno));
149 fail = 1;
150 close(fd);
151 continue;
152 }
153 if (dsize < MD_RESERVED_SECTORS*2) {
154 fprintf(stderr, Name ": %s is too small: %dK\n",
155 dname, dsize/2);
156 fail = 1;
157 close(fd);
158 continue;
159 }
160 freesize = MD_NEW_SIZE_SECTORS(dsize);
161 freesize /= 2;
162
163 if (size && freesize < size) {
164 fprintf(stderr, Name ": %s is smaller that given size."
165 " %dK < %dK + superblock\n", dname, freesize, size);
166 fail = 1;
167 close(fd);
168 continue;
169 }
170 if (maxdisc == NULL || (maxdisc && freesize > maxsize)) {
171 maxdisc = dname;
172 maxsize = freesize;
173 }
174 if (mindisc ==NULL || (mindisc && freesize < minsize)) {
175 mindisc = dname;
176 minsize = freesize;
177 }
178 warn |= check_ext2(fd, dname);
179 warn |= check_reiser(fd, dname);
180 warn |= check_raid(fd, dname);
181 close(fd);
182 }
183 if (fail) {
184 fprintf(stderr, Name ": create aborted\n");
185 return 1;
186 }
187 if (size == 0) {
188 if (mindisc == NULL) {
189 fprintf(stderr, Name ": no size and no drives given - aborting create.\n");
190 return 1;
191 }
192 size = minsize;
193 if (verbose && level>0)
194 fprintf(stderr, Name ": size set to %dK\n", size);
195 }
196 if (level >= 1 && ((maxsize-size)*100 > maxsize)) {
197 fprintf(stderr, Name ": largest drive (%s) exceed size (%dK) by more than 1%\n",
198 maxdisc, size);
199 warn = 1;
200 }
201
202 if (warn) {
203 if (runstop!= 1) {
204 if (!ask("Continue creating array? ")) {
205 fprintf(stderr, Name ": create aborted.\n");
206 return 1;
207 }
208 } else {
209 if (verbose)
210 fprintf(stderr, Name ": creation continuing despite oddities due to --run\n");
211 }
212 }
213
214 /* If this is raid5, we want to configure the last active slot
215 * as missing, so that a reconstruct happens (faster than re-parity)
216 */
217 if (force == 0 && level == 5 && first_missing >= raiddisks) {
218 insert_point = raiddisks-1;
219 sparedisks++;
220 array.active_disks--;
221 missing_disks++;
222 }
223
224 /* Ok, lets try some ioctls */
225
226 array.level = level;
227 array.size = size;
228 array.raid_disks = raiddisks;
229 /* The kernel should *know* what md_minor we are dealing
230 * with, but it chooses to trust me instead. Sigh
231 */
232 array.md_minor = 0;
233 if (fstat(mdfd, &stb)==0)
234 array.md_minor = MINOR(stb.st_rdev);
235 array.not_persistent = 0;
236 if (level == 5 && (insert_point < raiddisks || first_missing < raiddisks))
237 array.state = 1; /* clean, but one drive will be missing */
238 else
239 array.state = 0; /* not clean, but no errors */
240
241 /* There is lots of redundancy in these disk counts,
242 * raid_disks is the most meaningful value
243 * it describes the geometry of the array
244 * it is constant
245 * nr_disks is total number of used slots.
246 * it should be raid_disks+spare_disks
247 * spare_disks is the number of extra disks present
248 * see above
249 * active_disks is the number of working disks in
250 * active slots. (With raid_disks)
251 * working_disks is the total number of working disks,
252 * including spares
253 * failed_disks is the number of disks marked failed
254 *
255 * Ideally, the kernel would keep these (except raid_disks)
256 * up-to-date as we ADD_NEW_DISK, but it doesn't (yet).
257 * So for now, we assume that all raid and spare
258 * devices will be given.
259 */
260 array.spare_disks=sparedisks;
261 array.failed_disks=missing_disks;
262 array.nr_disks = array.working_disks + array.failed_disks;
263 array.layout = layout;
264 array.chunk_size = chunk*1024;
265
266 if (ioctl(mdfd, SET_ARRAY_INFO, &array)) {
267 fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
268 mddev, strerror(errno));
269 return 1;
270 }
271
272 for (i=0, dv = devlist ; dv ; dv=dv->next, i++) {
273 int fd;
274 struct stat stb;
275 mdu_disk_info_t disk;
276
277 disk.number = i;
278 if (i >= insert_point)
279 disk.number++;
280 disk.raid_disk = disk.number;
281 if (disk.raid_disk < raiddisks)
282 disk.state = 6; /* active and in sync */
283 else
284 disk.state = 0;
285 if (strcasecmp(dv->devname, "missing")==0) {
286 disk.major = 0;
287 disk.minor = 0;
288 disk.state = 1; /* faulty */
289 } else {
290 fd = open(dv->devname, O_RDONLY, 0);
291 if (fd < 0) {
292 fprintf(stderr, Name ": failed to open %s after earlier success - aborting\n",
293 dv->devname);
294 return 1;
295 }
296 fstat(fd, &stb);
297 disk.major = MAJOR(stb.st_rdev);
298 disk.minor = MINOR(stb.st_rdev);
299 close(fd);
300 }
301 if (ioctl(mdfd, ADD_NEW_DISK, &disk)) {
302 fprintf(stderr, Name ": ADD_NEW_DISK for %s failed: %s\n",
303 dv->devname, strerror(errno));
304 return 1;
305 }
306 }
307
308 if (insert_point < MD_SB_DISKS) {
309 mdu_disk_info_t disk;
310 disk.number = insert_point;
311 disk.raid_disk = disk.number;
312 disk.state = 1; /* faulty */
313 disk.major = disk.minor = 0;
314 ioctl(mdfd,ADD_NEW_DISK, &disk);
315 }
316
317 /* param is not actually used */
318 if (runstop == 1 || subdevs >= raiddisks) {
319 mdu_param_t param;
320 if (ioctl(mdfd, RUN_ARRAY, &param)) {
321 fprintf(stderr, Name ": RUN_ARRAY failed: %s\n",
322 strerror(errno));
323 return 1;
324 }
325 fprintf(stderr, Name ": array %s started.\n", mddev);
326 } else {
327 fprintf(stderr, Name ": not starting array - not enough discs.\n");
328 }
329 return 0;
330 }