]> git.ipfire.org Git - thirdparty/mdadm.git/blame - bitmap.c
DDF: compare_super_ddf: merge local info of other superblock
[thirdparty/mdadm.git] / bitmap.c
CommitLineData
c82f047c
NB
1/*
2 * mdadm - manage Linux "md" devices aka RAID arrays.
3 *
4 * Copyright (C) 2004 Paul Clements, SteelEye Technology, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
c82f047c 21#include "mdadm.h"
c82f047c 22
c82f047c
NB
23inline void sb_le_to_cpu(bitmap_super_t *sb)
24{
25 sb->magic = __le32_to_cpu(sb->magic);
26 sb->version = __le32_to_cpu(sb->version);
27 /* uuid gets no translation */
28 sb->events = __le64_to_cpu(sb->events);
29 sb->events_cleared = __le64_to_cpu(sb->events_cleared);
30 sb->state = __le32_to_cpu(sb->state);
31 sb->chunksize = __le32_to_cpu(sb->chunksize);
32 sb->daemon_sleep = __le32_to_cpu(sb->daemon_sleep);
33 sb->sync_size = __le64_to_cpu(sb->sync_size);
10ae45c1 34 sb->write_behind = __le32_to_cpu(sb->write_behind);
c82f047c
NB
35}
36
37inline void sb_cpu_to_le(bitmap_super_t *sb)
38{
39 sb_le_to_cpu(sb); /* these are really the same thing */
40}
41
42mapping_t bitmap_states[] = {
43 { "OK", 0 },
44 { "Out of date", 2 },
45 { NULL, -1 }
46};
47
48const char *bitmap_state(int state_num)
49{
50 char *state = map_num(bitmap_states, state_num);
51 return state ? state : "Unknown";
52}
53
54const char *human_chunksize(unsigned long bytes)
55{
56 static char buf[16];
57 char *suffixes[] = { "B", "KB", "MB", "GB", "TB", NULL };
58 int i = 0;
59
60 while (bytes >> 10) {
61 bytes >>= 10;
62 i++;
63 }
64
8f23b0b3 65 snprintf(buf, sizeof(buf), "%lu %s", bytes, suffixes[i]);
c82f047c
NB
66
67 return buf;
68}
69
70typedef struct bitmap_info_s {
71 bitmap_super_t sb;
72 unsigned long long total_bits;
73 unsigned long long dirty_bits;
74} bitmap_info_t;
75
76/* count the dirty bits in the first num_bits of byte */
77inline int count_dirty_bits_byte(char byte, int num_bits)
78{
79 int num = 0;
80
81 switch (num_bits) { /* fall through... */
82 case 8: if (byte & 128) num++;
83 case 7: if (byte & 64) num++;
84 case 6: if (byte & 32) num++;
85 case 5: if (byte & 16) num++;
86 case 4: if (byte & 8) num++;
87 case 3: if (byte & 4) num++;
88 case 2: if (byte & 2) num++;
89 case 1: if (byte & 1) num++;
90 default: break;
91 }
92
93 return num;
94}
95
96int count_dirty_bits(char *buf, int num_bits)
97{
98 int i, num = 0;
99
ca3b6696 100 for (i = 0; i < num_bits / 8; i++)
c82f047c
NB
101 num += count_dirty_bits_byte(buf[i], 8);
102
103 if (num_bits % 8) /* not an even byte boundary */
104 num += count_dirty_bits_byte(buf[i], num_bits % 8);
105
106 return num;
107}
108
109/* calculate the size of the bitmap given the array size and bitmap chunksize */
110unsigned long long bitmap_bits(unsigned long long array_size,
111 unsigned long chunksize)
112{
113 return (array_size * 512 + chunksize - 1) / chunksize;
114}
115
2a528478
N
116unsigned long bitmap_sectors(struct bitmap_super_s *bsb)
117{
118 unsigned long long bits = bitmap_bits(__le64_to_cpu(bsb->sync_size),
119 __le32_to_cpu(bsb->chunksize));
120 int bits_per_sector = 8*512;
121 return (bits + bits_per_sector - 1) / bits_per_sector;
122}
123
c82f047c
NB
124bitmap_info_t *bitmap_fd_read(int fd, int brief)
125{
4ccdb956
NB
126 /* Note: fd might be open O_DIRECT, so we must be
127 * careful to align reads properly
128 */
c82f047c
NB
129 unsigned long long total_bits = 0, read_bits = 0, dirty_bits = 0;
130 bitmap_info_t *info;
6416d527 131 void *buf;
f21e18ca 132 unsigned int n, skip;
4ccdb956 133
a7322ae1 134 if (posix_memalign(&buf, 4096, 8192) != 0) {
e7b84f9d 135 pr_err("failed to allocate 8192 bytes\n");
3d2c4fc7
DW
136 return NULL;
137 }
4ccdb956 138 n = read(fd, buf, 8192);
c82f047c 139
503975b9 140 info = xmalloc(sizeof(*info));
c82f047c 141
4ccdb956 142 if (n < sizeof(info->sb)) {
e7b84f9d
N
143 pr_err("failed to read superblock of bitmap "
144 "file: %s\n", strerror(errno));
c82f047c 145 free(info);
39c74d5e 146 free(buf);
c82f047c
NB
147 return NULL;
148 }
4ccdb956
NB
149 memcpy(&info->sb, buf, sizeof(info->sb));
150 skip = sizeof(info->sb);
c82f047c
NB
151
152 sb_le_to_cpu(&info->sb); /* convert superblock to CPU byte ordering */
aba69144 153
b47dff66 154 if (brief || info->sb.sync_size == 0 || info->sb.chunksize == 0)
c82f047c
NB
155 goto out;
156
157 /* read the rest of the file counting total bits and dirty bits --
158 * we stop when either:
159 * 1) we hit EOF, in which case we assume the rest of the bits (if any)
160 * are dirty
161 * 2) we've read the full bitmap, in which case we ignore any trailing
162 * data in the file
163 */
164 total_bits = bitmap_bits(info->sb.sync_size, info->sb.chunksize);
165
4ccdb956 166 while(read_bits < total_bits) {
c82f047c
NB
167 unsigned long long remaining = total_bits - read_bits;
168
4ccdb956
NB
169 if (n == 0) {
170 n = read(fd, buf, 8192);
171 skip = 0;
172 if (n <= 0)
173 break;
174 }
175 if (remaining > (n-skip) * 8) /* we want the full buffer */
176 remaining = (n-skip) * 8;
177
178 dirty_bits += count_dirty_bits(buf+skip, remaining);
c82f047c
NB
179
180 read_bits += remaining;
4ccdb956 181 n = 0;
c82f047c
NB
182 }
183
184 if (read_bits < total_bits) { /* file truncated... */
e7b84f9d 185 pr_err("WARNING: bitmap file is not large "
f9c25f1d
NB
186 "enough for array size %llu!\n\n",
187 (unsigned long long)info->sb.sync_size);
c82f047c
NB
188 total_bits = read_bits;
189 }
190out:
39c74d5e 191 free(buf);
c82f047c
NB
192 info->total_bits = total_bits;
193 info->dirty_bits = dirty_bits;
194 return info;
195}
196
34163fc7 197bitmap_info_t *bitmap_file_read(char *filename, int brief, struct supertype **stp)
c82f047c
NB
198{
199 int fd;
200 bitmap_info_t *info;
55935d51 201 struct stat stb;
34163fc7 202 struct supertype *st = *stp;
c82f047c 203
4ccdb956 204 if (stat(filename, &stb) < 0) {
e7b84f9d 205 pr_err("failed to find file %s: %s\n",
4ccdb956 206 filename, strerror(errno));
c82f047c
NB
207 return NULL;
208 }
55935d51 209 if ((S_IFMT & stb.st_mode) == S_IFBLK) {
9698df15 210 fd = open(filename, O_RDONLY|O_DIRECT);
4ccdb956 211 if (fd < 0) {
e7b84f9d 212 pr_err("failed to open bitmap file %s: %s\n",
4ccdb956
NB
213 filename, strerror(errno));
214 return NULL;
215 }
55935d51
NB
216 /* block device, so we are probably after an internal bitmap */
217 if (!st) st = guess_super(fd);
218 if (!st) {
219 /* just look at device... */
220 lseek(fd, 0, 0);
ebeb3663 221 } else if (!st->ss->locate_bitmap) {
e7b84f9d 222 pr_err("No bitmap possible with %s metadata\n",
ebeb3663
N
223 st->ss->name);
224 return NULL;
225 } else
3da92f27 226 st->ss->locate_bitmap(st, fd);
ebeb3663 227
34163fc7 228 *stp = st;
4ccdb956
NB
229 } else {
230 fd = open(filename, O_RDONLY|O_DIRECT);
231 if (fd < 0) {
e7b84f9d 232 pr_err("failed to open bitmap file %s: %s\n",
4ccdb956
NB
233 filename, strerror(errno));
234 return NULL;
235 }
55935d51 236 }
c82f047c
NB
237
238 info = bitmap_fd_read(fd, brief);
239 close(fd);
240 return info;
241}
242
34163fc7
NB
243__u32 swapl(__u32 l)
244{
245 char *c = (char*)&l;
246 char t= c[0];
247 c[0] = c[3];
248 c[3] = t;
249
250 t = c[1];
251 c[1] = c[2];
252 c[2] = t;
253 return l;
254}
55935d51 255int ExamineBitmap(char *filename, int brief, struct supertype *st)
c82f047c
NB
256{
257 /*
258 * Read the bitmap file and display its contents
259 */
260
261 bitmap_super_t *sb;
262 bitmap_info_t *info;
263 int rv = 1;
dfd4d8ee 264 char buf[64];
bf4fb153 265 int swap;
caa0f6c6 266 __u32 uuid32[4];
c82f047c 267
34163fc7 268 info = bitmap_file_read(filename, brief, &st);
c82f047c
NB
269 if (!info)
270 return rv;
271
272 sb = &info->sb;
273 printf(" Filename : %s\n", filename);
274 printf(" Magic : %08x\n", sb->magic);
275 if (sb->magic != BITMAP_MAGIC) {
e7b84f9d 276 pr_err("invalid bitmap magic 0x%x, the bitmap file appears to be corrupted\n", sb->magic);
c82f047c
NB
277 }
278 printf(" Version : %d\n", sb->version);
dcec9ee5
NB
279 if (sb->version < BITMAP_MAJOR_LO ||
280 sb->version > BITMAP_MAJOR_HI) {
e7b84f9d 281 pr_err("unknown bitmap version %d, either the bitmap file is corrupted or you need to upgrade your tools\n", sb->version);
c82f047c
NB
282 goto free_info;
283 }
284
285 rv = 0;
bf4fb153
NB
286 if (st)
287 swap = st->ss->swapuuid;
288 else
289#if __BYTE_ORDER == BIG_ENDIAN
290 swap = 0;
291#else
292 swap = 1;
293#endif
caa0f6c6
N
294 memcpy(uuid32, sb->uuid, 16);
295 if (swap)
296 printf(" UUID : %08x:%08x:%08x:%08x\n",
297 swapl(uuid32[0]),
298 swapl(uuid32[1]),
299 swapl(uuid32[2]),
300 swapl(uuid32[3]));
301 else
302 printf(" UUID : %08x:%08x:%08x:%08x\n",
303 uuid32[0],
304 uuid32[1],
305 uuid32[2],
306 uuid32[3]);
307
f9c25f1d
NB
308 printf(" Events : %llu\n", (unsigned long long)sb->events);
309 printf(" Events Cleared : %llu\n", (unsigned long long)sb->events_cleared);
c82f047c
NB
310 printf(" State : %s\n", bitmap_state(sb->state));
311 printf(" Chunksize : %s\n", human_chunksize(sb->chunksize));
312 printf(" Daemon : %ds flush period\n", sb->daemon_sleep);
dfd4d8ee
NB
313 if (sb->write_behind)
314 sprintf(buf, "Allow write behind, max %d", sb->write_behind);
315 else
316 sprintf(buf, "Normal");
317 printf(" Write Mode : %s\n", buf);
f9c25f1d 318 printf(" Sync Size : %llu%s\n", (unsigned long long)sb->sync_size/2,
f277ce36 319 human_size(sb->sync_size * 512));
c82f047c
NB
320 if (brief)
321 goto free_info;
322 printf(" Bitmap : %llu bits (chunks), %llu dirty (%2.1f%%)\n",
323 info->total_bits, info->dirty_bits,
6c9a5fa1 324 100.0 * info->dirty_bits / (info->total_bits?:1));
c82f047c
NB
325free_info:
326 free(info);
327 return rv;
328}
329
330int CreateBitmap(char *filename, int force, char uuid[16],
1bf4e2d9
NB
331 unsigned long chunksize, unsigned long daemon_sleep,
332 unsigned long write_behind,
dcec9ee5
NB
333 unsigned long long array_size /* sectors */,
334 int major)
c82f047c
NB
335{
336 /*
337 * Create a bitmap file with a superblock and (optionally) a full bitmap
338 */
339
340 FILE *fp;
341 int rv = 1;
342 char block[512];
343 bitmap_super_t sb;
344 long long bytes, filesize;
345
346 if (!force && access(filename, F_OK) == 0) {
e7b84f9d 347 pr_err("bitmap file %s already exists, use --force to overwrite\n", filename);
c82f047c
NB
348 return rv;
349 }
350
351 fp = fopen(filename, "w");
352 if (fp == NULL) {
e7b84f9d 353 pr_err("failed to open bitmap file %s: %s\n",
c82f047c
NB
354 filename, strerror(errno));
355 return rv;
356 }
357
1bfdbe01
NB
358 if (chunksize == UnSet) {
359 /* We don't want more than 2^21 chunks, as 2^11 fill up one
360 * 4K page (2 bytes per chunk), and 2^10 address of those
b39827de
NB
361 * fill up a 4K indexing page. 2^20 might be safer, especially
362 * on 64bit hosts, so use that.
1bfdbe01
NB
363 */
364 chunksize = DEFAULT_BITMAP_CHUNK;
b39827de 365 /* <<20 for 2^20 chunks, >>9 to convert bytes to sectors */
3e416561 366 while (array_size > ((unsigned long long)chunksize << (20-9)))
1bfdbe01
NB
367 chunksize <<= 1;
368 }
369
c82f047c
NB
370 memset(&sb, 0, sizeof(sb));
371 sb.magic = BITMAP_MAGIC;
dcec9ee5 372 sb.version = major;
c82f047c
NB
373 if (uuid != NULL)
374 memcpy(sb.uuid, uuid, 16);
375 sb.chunksize = chunksize;
376 sb.daemon_sleep = daemon_sleep;
dfd4d8ee 377 sb.write_behind = write_behind;
c82f047c
NB
378 sb.sync_size = array_size;
379
380 sb_cpu_to_le(&sb); /* convert to on-disk byte ordering */
381
382 if (fwrite(&sb, sizeof(sb), 1, fp) != 1) {
e7b84f9d 383 pr_err("failed to write superblock to bitmap file %s: %s\n", filename, strerror(errno));
c82f047c
NB
384 goto out;
385 }
386
387 /* calculate the size of the bitmap and write it to disk */
388 bytes = (bitmap_bits(array_size, chunksize) + 7) / 8;
389 if (!bytes) {
390 rv = 0;
391 goto out;
392 }
393
394 filesize = bytes + sizeof(sb);
395
396 memset(block, 0xff, sizeof(block));
397
398 while (bytes > 0) {
399 if (fwrite(block, sizeof(block), 1, fp) != 1) {
e7b84f9d 400 pr_err("failed to write bitmap file %s: %s\n", filename, strerror(errno));
c82f047c
NB
401 goto out;
402 }
403 bytes -= sizeof(block);
404 }
aba69144 405
c82f047c 406 rv = 0;
97a6748c 407 fflush(fp);
c82f047c 408 /* make the file be the right size (well, to the nearest byte) */
1e0d770c
NB
409 if (ftruncate(fileno(fp), filesize))
410 perror("ftrunace");
c82f047c
NB
411out:
412 fclose(fp);
413 if (rv)
414 unlink(filename); /* possibly corrupted, better get rid of it */
415 return rv;
416}
8131b493 417
bf4fb153 418int bitmap_update_uuid(int fd, int *uuid, int swap)
8131b493
NB
419{
420 struct bitmap_super_s bm;
9fca7d62
NB
421 if (lseek(fd, 0, 0) != 0)
422 return 1;
8131b493 423 if (read(fd, &bm, sizeof(bm)) != sizeof(bm))
9fca7d62 424 return 1;
8131b493 425 if (bm.magic != __cpu_to_le32(BITMAP_MAGIC))
9fca7d62 426 return 1;
350f29f9 427 copy_uuid(bm.uuid, uuid, swap);
9fca7d62
NB
428 if (lseek(fd, 0, 0) != 0)
429 return 2;
430 if (write(fd, &bm, sizeof(bm)) != sizeof(bm)) {
431 lseek(fd, 0, 0);
432 return 2;
433 }
8131b493 434 lseek(fd, 0, 0);
9fca7d62 435 return 0;
8131b493 436}