mdadm-1.0.1
[thirdparty/mdadm.git] / util.c
CommitLineData
64c4757e 1/*
9a9dab36 2 * mdadm - manage Linux "md" devices aka RAID arrays.
64c4757e 3 *
cd29a5c8 4 * Copyright (C) 2001-2002 Neil Brown <neilb@cse.unsw.edu.au>
64c4757e
NB
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
9a9dab36 30#include "mdadm.h"
64c4757e
NB
31#include "md_p.h"
32#include <sys/utsname.h>
33
34/*
35 * Parse a 128 bit uuid in 4 integers
36 * format is 32 hexx nibbles with options :.<space> separator
37 * If not exactly 32 hex digits are found, return 0
38 * else return 1
39 */
40int parse_uuid(char *str, int uuid[4])
41{
42 int hit = 0; /* number of Hex digIT */
43 int i;
44 char c;
45 for (i=0; i<4; i++) uuid[i]=0;
46
47 while ((c= *str++)) {
48 int n;
49 if (c>='0' && c<='9')
50 n = c-'0';
51 else if (c>='a' && c <= 'f')
52 n = 10 + c - 'a';
53 else if (c>='A' && c <= 'F')
54 n = 10 + c - 'A';
55 else if (strchr(":. -", c))
56 continue;
57 else return 0;
58
82b27616
NB
59 if (hit<32) {
60 uuid[hit/8] <<= 4;
61 uuid[hit/8] += n;
62 }
64c4757e
NB
63 hit++;
64 }
65 if (hit == 32)
66 return 1;
67 return 0;
68
69}
70
71
72/*
73 * Get the md version number.
74 * We use the RAID_VERSION ioctl if it is supported
75 * If not, but we have a block device with major '9', we assume
76 * 0.36.0
77 *
78 * Return version number as 24 but number - assume version parts
79 * always < 255
80 */
81
82int md_get_version(int fd)
83{
84 struct stat stb;
85 mdu_version_t vers;
86
87 if (fstat(fd, &stb)<0)
88 return -1;
89 if ((S_IFMT&stb.st_mode) != S_IFBLK)
90 return -1;
91
92 if (ioctl(fd, RAID_VERSION, &vers) == 0)
682c7051 93 return (vers.major*10000) + (vers.minor*100) + vers.patchlevel;
64c4757e
NB
94
95 if (MAJOR(stb.st_rdev) == MD_MAJOR)
682c7051 96 return (3600);
64c4757e
NB
97 return -1;
98}
99
100
101int get_linux_version()
102{
103 struct utsname name;
104 int a,b,c;
105 if (uname(&name) <0)
106 return -1;
107
108 if (sscanf(name.release, "%d.%d.%d", &a,&b,&c)!= 3)
109 return -1;
682c7051 110 return (a*1000000)+(b*1000)+c;
64c4757e
NB
111}
112
113int enough(int level, int raid_disks, int avail_disks)
114{
115 switch (level) {
e0d19036
NB
116 case -4:
117 return avail_disks>= 1;
64c4757e
NB
118 case -1:
119 case 0:
120 return avail_disks == raid_disks;
121 case 1:
122 return avail_disks >= 1;
123 case 4:
124 case 5:
125 return avail_disks >= raid_disks-1;
126 default:
127 return 0;
128 }
129}
130
131int same_uuid(int a[4], int b[4])
132{
133 if (a[0]==b[0] &&
134 a[1]==b[1] &&
135 a[2]==b[2] &&
136 a[3]==b[3])
137 return 1;
138 return 0;
139}
140
141void uuid_from_super(int uuid[4], mdp_super_t *super)
142{
143 uuid[0] = super->set_uuid0;
144 if (super->minor_version >= 90) {
145 uuid[1] = super->set_uuid1;
146 uuid[2] = super->set_uuid2;
147 uuid[3] = super->set_uuid3;
148 } else {
149 uuid[1] = 0;
150 uuid[2] = 0;
151 uuid[3] = 0;
152 }
153}
154
155int compare_super(mdp_super_t *first, mdp_super_t *second)
156{
157 /*
158 * return:
159 * 0 same, or first was empty, and second was copied
160 * 1 second had wrong number
161 * 2 wrong uuid
162 * 3 wrong other info
163 */
164 int uuid1[4], uuid2[4];
165 if (second->md_magic != MD_SB_MAGIC)
166 return 1;
167 if (first-> md_magic != MD_SB_MAGIC) {
168 memcpy(first, second, sizeof(*first));
169 return 0;
170 }
171
172 uuid_from_super(uuid1, first);
173 uuid_from_super(uuid2, second);
174 if (!same_uuid(uuid1, uuid2))
175 return 2;
176 if (first->major_version != second->major_version ||
177 first->minor_version != second->minor_version ||
178 first->patch_version != second->patch_version ||
179 first->gvalid_words != second->gvalid_words ||
180 first->ctime != second->ctime ||
181 first->level != second->level ||
182 first->size != second->size ||
183 first->raid_disks != second->raid_disks )
184 return 3;
185
186 return 0;
187}
188
189int load_super(int fd, mdp_super_t *super)
190{
191 /* try to read in the superblock
192 *
193 * return
194 * 0 - success
195 * 1 - no block size
196 * 2 - too small
197 * 3 - no seek
198 * 4 - no read
199 * 5 - no magic
200 * 6 - wrong major version
201 */
e0d19036
NB
202 unsigned long size;
203 unsigned long long offset;
64c4757e
NB
204
205 if (ioctl(fd, BLKGETSIZE, &size))
206 return 1;
207
208 if (size < MD_RESERVED_SECTORS*2)
209 return 2;
210
211 offset = MD_NEW_SIZE_SECTORS(size);
212
213 offset *= 512;
214
215 if (lseek64(fd, offset, 0)< 0LL)
216 return 3;
217
682c7051 218 if (read(fd, super, sizeof(*super)) != sizeof(*super))
64c4757e
NB
219 return 4;
220
221 if (super->md_magic != MD_SB_MAGIC)
222 return 5;
223
224 if (super->major_version != 0)
225 return 6;
226 return 0;
227}
228
82b27616
NB
229int store_super(int fd, mdp_super_t *super)
230{
231 long size;
232 long long offset;
233
234 if (ioctl(fd, BLKGETSIZE, &size))
235 return 1;
236
237 if (size < MD_RESERVED_SECTORS*2)
238 return 2;
239
240 offset = MD_NEW_SIZE_SECTORS(size);
241
242 offset *= 512;
243
244 if (lseek64(fd, offset, 0)< 0LL)
245 return 3;
246
247 if (write(fd, super, sizeof(*super)) != sizeof(*super))
248 return 4;
249
250 return 0;
251}
252
253
682c7051
NB
254
255int check_ext2(int fd, char *name)
256{
257 /*
258 * Check for an ext2fs file system.
259 * Superblock is always 1K at 1K offset
260 *
261 * s_magic is le16 at 56 == 0xEF53
262 * report mtime - le32 at 44
263 * blocks - le32 at 4
264 * logblksize - le32 at 24
265 */
266 unsigned char sb[1024];
267 time_t mtime;
268 int size, bsize;
269 if (lseek(fd, 1024,0)!= 1024)
270 return 0;
271 if (read(fd, sb, 1024)!= 1024)
272 return 0;
273 if (sb[56] != 0x53 || sb[57] != 0xef)
274 return 0;
275
276 mtime = sb[44]|(sb[45]|(sb[46]|sb[47]<<8)<<8)<<8;
277 bsize = sb[24]|(sb[25]|(sb[26]|sb[27]<<8)<<8)<<8;
278 size = sb[4]|(sb[5]|(sb[6]|sb[7]<<8)<<8)<<8;
279 fprintf(stderr, Name ": %s appears to contain an ext2fs file system\n",
280 name);
281 fprintf(stderr," size=%dK mtime=%s",
282 size*(1<<bsize), ctime(&mtime));
283 return 1;
284}
285
286int check_reiser(int fd, char *name)
287{
288 /*
289 * superblock is at 64K
290 * size is 1024;
291 * Magic string "ReIsErFs" or "ReIsEr2Fs" at 52
292 *
293 */
294 unsigned char sb[1024];
295 int size;
296 if (lseek(fd, 64*1024, 0) != 64*1024)
297 return 0;
298 if (read(fd, sb, 1024) != 1024)
299 return 0;
300 if (strncmp(sb+52, "ReIsErFs",8)!=0 &&
301 strncmp(sb+52, "ReIsEr2Fs",9)!=0)
302 return 0;
303 fprintf(stderr, Name ": %s appears to contain a reiserfs file system\n",name);
304 size = sb[0]|(sb[1]|(sb[2]|sb[3]<<8)<<8)<<8;
305 fprintf(stderr, " size = %dK\n", size*4);
306
307 return 1;
308}
309
310int check_raid(int fd, char *name)
311{
312 mdp_super_t super;
313 time_t crtime;
314 if (load_super(fd, &super))
315 return 0;
316 /* Looks like a raid array .. */
317 fprintf(stderr, Name ": %s appear to be part of a raid array:\n",
318 name);
319 crtime = super.ctime;
b83d95f3 320 fprintf(stderr, " level=%d devices=%d ctime=%s",
682c7051
NB
321 super.level, super.raid_disks, ctime(&crtime));
322 return 1;
323}
324
325
326int ask(char *mesg)
327{
328 char *add = "";
329 int i;
330 for (i=0; i<5; i++) {
331 char buf[100];
332 fprintf(stderr, "%s%s", mesg, add);
333 fflush(stderr);
334 if (fgets(buf, 100, stdin)==NULL)
335 return 0;
336 if (buf[0]=='y' || buf[0]=='Y')
337 return 1;
338 if (buf[0]=='n' || buf[0]=='N')
339 return 0;
340 add = "(y/n) ";
341 }
342 fprintf(stderr, Name ": assuming 'no'\n");
343 return 0;
344}
345
346char *map_num(mapping_t *map, int num)
347{
348 while (map->name) {
349 if (map->num == num)
350 return map->name;
351 map++;
352 }
353 return NULL;
354}
355
356int map_name(mapping_t *map, char *name)
357{
358 while (map->name) {
359 if (strcmp(map->name, name)==0)
360 return map->num;
361 map++;
362 }
363 return -10;
364}
82b27616
NB
365
366/*
367 * convert a major/minor pair for a block device into a name in /dev, if possible.
368 * On the first call, walk /dev collecting name.
369 * Put them in a simple linked listfor now.
370 */
371struct devmap {
372 int major, minor;
373 char *name;
374 struct devmap *next;
375} *devlist = NULL;
376int devlist_ready = 0;
377
378#define __USE_XOPEN_EXTENDED
379#include <ftw.h>
380
381
382int add_dev(const char *name, const struct stat *stb, int flag, struct FTW *s)
383{
384 if ((stb->st_mode&S_IFMT)== S_IFBLK) {
385 char *n = strdup(name);
386 struct devmap *dm = malloc(sizeof(*dm));
387 if (dm) {
388 dm->major = MAJOR(stb->st_rdev);
389 dm->minor = MINOR(stb->st_rdev);
390 dm->name = n;
391 dm->next = devlist;
392 devlist = dm;
393 }
394 }
395 return 0;
396}
397
398char *map_dev(int major, int minor)
399{
400 struct devmap *p;
401 if (!devlist_ready) {
402 nftw("/dev", add_dev, 10, FTW_PHYS);
403 devlist_ready=1;
404 }
405
406 for (p=devlist; p; p=p->next)
407 if (p->major == major &&
408 p->minor == minor)
409 return p->name;
410 return NULL;
411}
412
413
414int calc_sb_csum(mdp_super_t *super)
415{
416 unsigned int oldcsum = super->sb_csum;
56eb10c0 417 unsigned long long newcsum = 0;
82b27616
NB
418 unsigned long csum;
419 int i;
420 unsigned int *superc = (int*) super;
421 super->sb_csum = 0;
422
423 for(i=0; i<MD_SB_BYTES/4; i++)
424 newcsum+= superc[i];
425 csum = (newcsum& 0xffffffff) + (newcsum>>32);
426 super->sb_csum = oldcsum;
427 return csum;
428}
cd29a5c8 429
56eb10c0 430char *human_size(long long bytes)
cd29a5c8
NB
431{
432 static char buf[30];
56eb10c0 433
cd29a5c8 434
56eb10c0 435 if (bytes < 5000*1024)
cd29a5c8 436 buf[0]=0;
56eb10c0 437 else if (bytes < 2*1024LL*1024LL*1024LL)
e0d19036 438 sprintf(buf, " (%ld.%02ld MiB %ld.%02ld MB)",
56eb10c0 439 (long)(bytes>>20),
bd526cee 440 (long)((bytes&0xfffff)+0x100000/200)/(0x100000/100),
56eb10c0 441 (long)(bytes/1000/1000),
bd526cee 442 (long)(((bytes%1000000)+5000)/10000)
56eb10c0 443 );
cd29a5c8 444 else
e0d19036 445 sprintf(buf, " (%ld.%02ld GiB %ld.%02ld GB)",
56eb10c0 446 (long)(bytes>>30),
bd526cee 447 (long)(((bytes>>10)&0xfffff)+0x100000/200)/(0x100000/100),
56eb10c0 448 (long)(bytes/1000LL/1000LL/1000LL),
bd526cee 449 (long)((((bytes/1000)%1000000)+50000)/10000)
56eb10c0 450 );
cd29a5c8
NB
451 return buf;
452}
e0d19036
NB
453
454char *human_size_brief(long long bytes)
455{
456 static char buf[30];
457
458
459 if (bytes < 5000*1024)
460 sprintf(buf, "%ld.%02ldKiB",
bd526cee 461 (long)(bytes>>10), (long)(((bytes&1023)*100+512)/1024)
e0d19036
NB
462 );
463 else if (bytes < 2*1024LL*1024LL*1024LL)
464 sprintf(buf, "%ld.%02ldMiB",
465 (long)(bytes>>20),
bd526cee 466 (long)((bytes&0xfffff)+0x100000/200)/(0x100000/100)
e0d19036
NB
467 );
468 else
469 sprintf(buf, "%ld.%02ldGiB",
470 (long)(bytes>>30),
bd526cee 471 (long)(((bytes>>10)&0xfffff)+0x100000/200)/(0x100000/100)
e0d19036
NB
472 );
473 return buf;
474}
475
476
477#define MD_MAJOR 9
478char *get_md_name(int dev)
479{
480 /* find /dev/md%d or /dev/md/%d or make a device /dev/.tmp.md%d */
481 static char devname[50];
482 struct stat stb;
483 dev_t rdev = MKDEV(MD_MAJOR, dev);
484
485 sprintf(devname, "/dev/md%d", dev);
486 if (stat(devname, &stb) == 0
487 && (S_IFMT&stb.st_mode) == S_IFBLK
488 && (stb.st_rdev == rdev))
489 return devname;
490
491 sprintf(devname, "/dev/md/%d", dev);
492 if (stat(devname, &stb) == 0
493 && (S_IFMT&stb.st_mode) == S_IFBLK
494 && (stb.st_rdev == rdev))
495 return devname;
496
497 sprintf(devname, "/dev/.tmp.md%d", dev);
498 if (mknod(devname, S_IFBLK | 0600, rdev) == -1)
499 return NULL;
500
501 if (stat(devname, &stb) == 0
502 && (S_IFMT&stb.st_mode) == S_IFBLK
503 && (stb.st_rdev == rdev))
504 return devname;
505 unlink(devname);
506 return NULL;
507}
508
509void put_md_name(char *name)
510{
511 if (strncmp(name, "/dev/.tmp.md", 12)==0)
512 unlink(name);
513}