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Merge branch 'master' into devel-3.0
[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
NB
22
23#define min(a,b) (((a) < (b)) ? (a) : (b))
24
25inline void sb_le_to_cpu(bitmap_super_t *sb)
26{
27 sb->magic = __le32_to_cpu(sb->magic);
28 sb->version = __le32_to_cpu(sb->version);
29 /* uuid gets no translation */
30 sb->events = __le64_to_cpu(sb->events);
31 sb->events_cleared = __le64_to_cpu(sb->events_cleared);
32 sb->state = __le32_to_cpu(sb->state);
33 sb->chunksize = __le32_to_cpu(sb->chunksize);
34 sb->daemon_sleep = __le32_to_cpu(sb->daemon_sleep);
35 sb->sync_size = __le64_to_cpu(sb->sync_size);
10ae45c1 36 sb->write_behind = __le32_to_cpu(sb->write_behind);
c82f047c
NB
37}
38
39inline void sb_cpu_to_le(bitmap_super_t *sb)
40{
41 sb_le_to_cpu(sb); /* these are really the same thing */
42}
43
44mapping_t bitmap_states[] = {
45 { "OK", 0 },
46 { "Out of date", 2 },
47 { NULL, -1 }
48};
49
50const char *bitmap_state(int state_num)
51{
52 char *state = map_num(bitmap_states, state_num);
53 return state ? state : "Unknown";
54}
55
56const char *human_chunksize(unsigned long bytes)
57{
58 static char buf[16];
59 char *suffixes[] = { "B", "KB", "MB", "GB", "TB", NULL };
60 int i = 0;
61
62 while (bytes >> 10) {
63 bytes >>= 10;
64 i++;
65 }
66
8f23b0b3 67 snprintf(buf, sizeof(buf), "%lu %s", bytes, suffixes[i]);
c82f047c
NB
68
69 return buf;
70}
71
72typedef struct bitmap_info_s {
73 bitmap_super_t sb;
74 unsigned long long total_bits;
75 unsigned long long dirty_bits;
76} bitmap_info_t;
77
78/* count the dirty bits in the first num_bits of byte */
79inline int count_dirty_bits_byte(char byte, int num_bits)
80{
81 int num = 0;
82
83 switch (num_bits) { /* fall through... */
84 case 8: if (byte & 128) num++;
85 case 7: if (byte & 64) num++;
86 case 6: if (byte & 32) num++;
87 case 5: if (byte & 16) num++;
88 case 4: if (byte & 8) num++;
89 case 3: if (byte & 4) num++;
90 case 2: if (byte & 2) num++;
91 case 1: if (byte & 1) num++;
92 default: break;
93 }
94
95 return num;
96}
97
98int count_dirty_bits(char *buf, int num_bits)
99{
100 int i, num = 0;
101
102 for (i=0; i < num_bits / 8; i++)
103 num += count_dirty_bits_byte(buf[i], 8);
104
105 if (num_bits % 8) /* not an even byte boundary */
106 num += count_dirty_bits_byte(buf[i], num_bits % 8);
107
108 return num;
109}
110
111/* calculate the size of the bitmap given the array size and bitmap chunksize */
112unsigned long long bitmap_bits(unsigned long long array_size,
113 unsigned long chunksize)
114{
115 return (array_size * 512 + chunksize - 1) / chunksize;
116}
117
2a528478
N
118unsigned long bitmap_sectors(struct bitmap_super_s *bsb)
119{
120 unsigned long long bits = bitmap_bits(__le64_to_cpu(bsb->sync_size),
121 __le32_to_cpu(bsb->chunksize));
122 int bits_per_sector = 8*512;
123 return (bits + bits_per_sector - 1) / bits_per_sector;
124}
125
126
c82f047c
NB
127bitmap_info_t *bitmap_fd_read(int fd, int brief)
128{
4ccdb956
NB
129 /* Note: fd might be open O_DIRECT, so we must be
130 * careful to align reads properly
131 */
c82f047c
NB
132 unsigned long long total_bits = 0, read_bits = 0, dirty_bits = 0;
133 bitmap_info_t *info;
6416d527 134 void *buf;
4ccdb956
NB
135 int n, skip;
136
3d2c4fc7
DW
137 if (posix_memalign(&buf, 512, 8192) != 0) {
138 fprintf(stderr, Name ": failed to allocate 8192 bytes\n");
139 return NULL;
140 }
4ccdb956 141 n = read(fd, buf, 8192);
c82f047c
NB
142
143 info = malloc(sizeof(*info));
144 if (info == NULL) {
838acbc2
NB
145#if __GNUC__ < 3
146 fprintf(stderr, Name ": failed to allocate %d bytes\n",
147 (int)sizeof(*info));
148#else
f9c25f1d 149 fprintf(stderr, Name ": failed to allocate %zd bytes\n",
c82f047c 150 sizeof(*info));
838acbc2 151#endif
c82f047c
NB
152 return NULL;
153 }
154
4ccdb956 155 if (n < sizeof(info->sb)) {
c82f047c
NB
156 fprintf(stderr, Name ": failed to read superblock of bitmap "
157 "file: %s\n", strerror(errno));
158 free(info);
159 return NULL;
160 }
4ccdb956
NB
161 memcpy(&info->sb, buf, sizeof(info->sb));
162 skip = sizeof(info->sb);
c82f047c
NB
163
164 sb_le_to_cpu(&info->sb); /* convert superblock to CPU byte ordering */
aba69144 165
c82f047c
NB
166 if (brief || info->sb.sync_size == 0)
167 goto out;
168
169 /* read the rest of the file counting total bits and dirty bits --
170 * we stop when either:
171 * 1) we hit EOF, in which case we assume the rest of the bits (if any)
172 * are dirty
173 * 2) we've read the full bitmap, in which case we ignore any trailing
174 * data in the file
175 */
176 total_bits = bitmap_bits(info->sb.sync_size, info->sb.chunksize);
177
4ccdb956 178 while(read_bits < total_bits) {
c82f047c
NB
179 unsigned long long remaining = total_bits - read_bits;
180
4ccdb956
NB
181 if (n == 0) {
182 n = read(fd, buf, 8192);
183 skip = 0;
184 if (n <= 0)
185 break;
186 }
187 if (remaining > (n-skip) * 8) /* we want the full buffer */
188 remaining = (n-skip) * 8;
189
190 dirty_bits += count_dirty_bits(buf+skip, remaining);
c82f047c
NB
191
192 read_bits += remaining;
4ccdb956 193 n = 0;
c82f047c
NB
194 }
195
196 if (read_bits < total_bits) { /* file truncated... */
197 fprintf(stderr, Name ": WARNING: bitmap file is not large "
f9c25f1d
NB
198 "enough for array size %llu!\n\n",
199 (unsigned long long)info->sb.sync_size);
c82f047c
NB
200 total_bits = read_bits;
201 }
202out:
203 info->total_bits = total_bits;
204 info->dirty_bits = dirty_bits;
205 return info;
206}
207
34163fc7 208bitmap_info_t *bitmap_file_read(char *filename, int brief, struct supertype **stp)
c82f047c
NB
209{
210 int fd;
211 bitmap_info_t *info;
55935d51 212 struct stat stb;
34163fc7 213 struct supertype *st = *stp;
c82f047c 214
4ccdb956
NB
215 if (stat(filename, &stb) < 0) {
216 fprintf(stderr, Name ": failed to find file %s: %s\n",
217 filename, strerror(errno));
c82f047c
NB
218 return NULL;
219 }
55935d51 220 if ((S_IFMT & stb.st_mode) == S_IFBLK) {
4ccdb956
NB
221 fd = open(filename, O_RDONLY);
222 if (fd < 0) {
223 fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
224 filename, strerror(errno));
225 return NULL;
226 }
55935d51
NB
227 /* block device, so we are probably after an internal bitmap */
228 if (!st) st = guess_super(fd);
229 if (!st) {
230 /* just look at device... */
231 lseek(fd, 0, 0);
aba69144 232 } else {
3da92f27 233 st->ss->locate_bitmap(st, fd);
55935d51 234 }
34163fc7
NB
235 ioctl(fd, BLKFLSBUF, 0); /* make sure we read current data */
236 *stp = st;
4ccdb956
NB
237 } else {
238 fd = open(filename, O_RDONLY|O_DIRECT);
239 if (fd < 0) {
240 fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
241 filename, strerror(errno));
242 return NULL;
243 }
55935d51 244 }
c82f047c
NB
245
246 info = bitmap_fd_read(fd, brief);
247 close(fd);
248 return info;
249}
250
34163fc7
NB
251__u32 swapl(__u32 l)
252{
253 char *c = (char*)&l;
254 char t= c[0];
255 c[0] = c[3];
256 c[3] = t;
257
258 t = c[1];
259 c[1] = c[2];
260 c[2] = t;
261 return l;
262}
55935d51 263int ExamineBitmap(char *filename, int brief, struct supertype *st)
c82f047c
NB
264{
265 /*
266 * Read the bitmap file and display its contents
267 */
268
269 bitmap_super_t *sb;
270 bitmap_info_t *info;
271 int rv = 1;
dfd4d8ee 272 char buf[64];
bf4fb153 273 int swap;
c82f047c 274
34163fc7 275 info = bitmap_file_read(filename, brief, &st);
c82f047c
NB
276 if (!info)
277 return rv;
278
279 sb = &info->sb;
280 printf(" Filename : %s\n", filename);
281 printf(" Magic : %08x\n", sb->magic);
282 if (sb->magic != BITMAP_MAGIC) {
283 fprintf(stderr, Name ": invalid bitmap magic 0x%x, the bitmap file appears to be corrupted\n", sb->magic);
284 }
285 printf(" Version : %d\n", sb->version);
dcec9ee5
NB
286 if (sb->version < BITMAP_MAJOR_LO ||
287 sb->version > BITMAP_MAJOR_HI) {
c82f047c
NB
288 fprintf(stderr, Name ": unknown bitmap version %d, either the bitmap file is corrupted or you need to upgrade your tools\n", sb->version);
289 goto free_info;
290 }
291
292 rv = 0;
bf4fb153
NB
293 if (st)
294 swap = st->ss->swapuuid;
295 else
296#if __BYTE_ORDER == BIG_ENDIAN
297 swap = 0;
298#else
299 swap = 1;
300#endif
301 if (swap) {
302 printf(" UUID : %08x:%08x:%08x:%08x\n",
34163fc7
NB
303 swapl(*(__u32 *)(sb->uuid+0)),
304 swapl(*(__u32 *)(sb->uuid+4)),
305 swapl(*(__u32 *)(sb->uuid+8)),
306 swapl(*(__u32 *)(sb->uuid+12)));
307 } else {
bf4fb153 308 printf(" UUID : %08x:%08x:%08x:%08x\n",
c82f047c
NB
309 *(__u32 *)(sb->uuid+0),
310 *(__u32 *)(sb->uuid+4),
311 *(__u32 *)(sb->uuid+8),
312 *(__u32 *)(sb->uuid+12));
34163fc7 313 }
f9c25f1d
NB
314 printf(" Events : %llu\n", (unsigned long long)sb->events);
315 printf(" Events Cleared : %llu\n", (unsigned long long)sb->events_cleared);
c82f047c
NB
316 printf(" State : %s\n", bitmap_state(sb->state));
317 printf(" Chunksize : %s\n", human_chunksize(sb->chunksize));
318 printf(" Daemon : %ds flush period\n", sb->daemon_sleep);
dfd4d8ee
NB
319 if (sb->write_behind)
320 sprintf(buf, "Allow write behind, max %d", sb->write_behind);
321 else
322 sprintf(buf, "Normal");
323 printf(" Write Mode : %s\n", buf);
f9c25f1d 324 printf(" Sync Size : %llu%s\n", (unsigned long long)sb->sync_size/2,
f277ce36 325 human_size(sb->sync_size * 512));
c82f047c
NB
326 if (brief)
327 goto free_info;
328 printf(" Bitmap : %llu bits (chunks), %llu dirty (%2.1f%%)\n",
329 info->total_bits, info->dirty_bits,
330 100.0 * info->dirty_bits / (info->total_bits + 1));
331free_info:
332 free(info);
333 return rv;
334}
335
336int CreateBitmap(char *filename, int force, char uuid[16],
1bf4e2d9
NB
337 unsigned long chunksize, unsigned long daemon_sleep,
338 unsigned long write_behind,
dcec9ee5
NB
339 unsigned long long array_size /* sectors */,
340 int major)
c82f047c
NB
341{
342 /*
343 * Create a bitmap file with a superblock and (optionally) a full bitmap
344 */
345
346 FILE *fp;
347 int rv = 1;
348 char block[512];
349 bitmap_super_t sb;
350 long long bytes, filesize;
351
352 if (!force && access(filename, F_OK) == 0) {
353 fprintf(stderr, Name ": bitmap file %s already exists, use --force to overwrite\n", filename);
354 return rv;
355 }
356
357 fp = fopen(filename, "w");
358 if (fp == NULL) {
359 fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
360 filename, strerror(errno));
361 return rv;
362 }
363
1bfdbe01
NB
364 if (chunksize == UnSet) {
365 /* We don't want more than 2^21 chunks, as 2^11 fill up one
366 * 4K page (2 bytes per chunk), and 2^10 address of those
b39827de
NB
367 * fill up a 4K indexing page. 2^20 might be safer, especially
368 * on 64bit hosts, so use that.
1bfdbe01
NB
369 */
370 chunksize = DEFAULT_BITMAP_CHUNK;
b39827de
NB
371 /* <<20 for 2^20 chunks, >>9 to convert bytes to sectors */
372 while (array_size > (chunksize << (20-9)))
1bfdbe01
NB
373 chunksize <<= 1;
374 }
375
c82f047c
NB
376 memset(&sb, 0, sizeof(sb));
377 sb.magic = BITMAP_MAGIC;
dcec9ee5 378 sb.version = major;
c82f047c
NB
379 if (uuid != NULL)
380 memcpy(sb.uuid, uuid, 16);
381 sb.chunksize = chunksize;
382 sb.daemon_sleep = daemon_sleep;
dfd4d8ee 383 sb.write_behind = write_behind;
c82f047c
NB
384 sb.sync_size = array_size;
385
386 sb_cpu_to_le(&sb); /* convert to on-disk byte ordering */
387
388 if (fwrite(&sb, sizeof(sb), 1, fp) != 1) {
389 fprintf(stderr, Name ": failed to write superblock to bitmap file %s: %s\n", filename, strerror(errno));
390 goto out;
391 }
392
393 /* calculate the size of the bitmap and write it to disk */
394 bytes = (bitmap_bits(array_size, chunksize) + 7) / 8;
395 if (!bytes) {
396 rv = 0;
397 goto out;
398 }
399
400 filesize = bytes + sizeof(sb);
401
402 memset(block, 0xff, sizeof(block));
403
404 while (bytes > 0) {
405 if (fwrite(block, sizeof(block), 1, fp) != 1) {
406 fprintf(stderr, Name ": failed to write bitmap file %s: %s\n", filename, strerror(errno));
407 goto out;
408 }
409 bytes -= sizeof(block);
410 }
aba69144 411
c82f047c 412 rv = 0;
97a6748c 413 fflush(fp);
c82f047c 414 /* make the file be the right size (well, to the nearest byte) */
1e0d770c
NB
415 if (ftruncate(fileno(fp), filesize))
416 perror("ftrunace");
c82f047c
NB
417out:
418 fclose(fp);
419 if (rv)
420 unlink(filename); /* possibly corrupted, better get rid of it */
421 return rv;
422}
8131b493 423
bf4fb153 424int bitmap_update_uuid(int fd, int *uuid, int swap)
8131b493
NB
425{
426 struct bitmap_super_s bm;
9fca7d62
NB
427 if (lseek(fd, 0, 0) != 0)
428 return 1;
8131b493 429 if (read(fd, &bm, sizeof(bm)) != sizeof(bm))
9fca7d62 430 return 1;
8131b493 431 if (bm.magic != __cpu_to_le32(BITMAP_MAGIC))
9fca7d62 432 return 1;
350f29f9 433 copy_uuid(bm.uuid, uuid, swap);
9fca7d62
NB
434 if (lseek(fd, 0, 0) != 0)
435 return 2;
436 if (write(fd, &bm, sizeof(bm)) != sizeof(bm)) {
437 lseek(fd, 0, 0);
438 return 2;
439 }
8131b493 440 lseek(fd, 0, 0);
9fca7d62 441 return 0;
8131b493 442}