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Correctly abort level change when reshape_array fails.
[thirdparty/mdadm.git] / bitmap.c
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
21 #include "mdadm.h"
22
23 inline 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);
34 sb->write_behind = __le32_to_cpu(sb->write_behind);
35 }
36
37 inline void sb_cpu_to_le(bitmap_super_t *sb)
38 {
39 sb_le_to_cpu(sb); /* these are really the same thing */
40 }
41
42 mapping_t bitmap_states[] = {
43 { "OK", 0 },
44 { "Out of date", 2 },
45 { NULL, -1 }
46 };
47
48 const char *bitmap_state(int state_num)
49 {
50 char *state = map_num(bitmap_states, state_num);
51 return state ? state : "Unknown";
52 }
53
54 const 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
65 snprintf(buf, sizeof(buf), "%lu %s", bytes, suffixes[i]);
66
67 return buf;
68 }
69
70 typedef 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 */
77 inline 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
96 int count_dirty_bits(char *buf, int num_bits)
97 {
98 int i, num = 0;
99
100 for (i=0; i < num_bits / 8; i++)
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 */
110 unsigned long long bitmap_bits(unsigned long long array_size,
111 unsigned long chunksize)
112 {
113 return (array_size * 512 + chunksize - 1) / chunksize;
114 }
115
116 unsigned 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
124
125 bitmap_info_t *bitmap_fd_read(int fd, int brief)
126 {
127 /* Note: fd might be open O_DIRECT, so we must be
128 * careful to align reads properly
129 */
130 unsigned long long total_bits = 0, read_bits = 0, dirty_bits = 0;
131 bitmap_info_t *info;
132 void *buf;
133 unsigned int n, skip;
134
135 if (posix_memalign(&buf, 512, 8192) != 0) {
136 fprintf(stderr, Name ": failed to allocate 8192 bytes\n");
137 return NULL;
138 }
139 n = read(fd, buf, 8192);
140
141 info = malloc(sizeof(*info));
142 if (info == NULL) {
143 #if __GNUC__ < 3
144 fprintf(stderr, Name ": failed to allocate %d bytes\n",
145 (int)sizeof(*info));
146 #else
147 fprintf(stderr, Name ": failed to allocate %zd bytes\n",
148 sizeof(*info));
149 #endif
150 return NULL;
151 }
152
153 if (n < sizeof(info->sb)) {
154 fprintf(stderr, Name ": failed to read superblock of bitmap "
155 "file: %s\n", strerror(errno));
156 free(info);
157 return NULL;
158 }
159 memcpy(&info->sb, buf, sizeof(info->sb));
160 skip = sizeof(info->sb);
161
162 sb_le_to_cpu(&info->sb); /* convert superblock to CPU byte ordering */
163
164 if (brief || info->sb.sync_size == 0 || info->sb.chunksize == 0)
165 goto out;
166
167 /* read the rest of the file counting total bits and dirty bits --
168 * we stop when either:
169 * 1) we hit EOF, in which case we assume the rest of the bits (if any)
170 * are dirty
171 * 2) we've read the full bitmap, in which case we ignore any trailing
172 * data in the file
173 */
174 total_bits = bitmap_bits(info->sb.sync_size, info->sb.chunksize);
175
176 while(read_bits < total_bits) {
177 unsigned long long remaining = total_bits - read_bits;
178
179 if (n == 0) {
180 n = read(fd, buf, 8192);
181 skip = 0;
182 if (n <= 0)
183 break;
184 }
185 if (remaining > (n-skip) * 8) /* we want the full buffer */
186 remaining = (n-skip) * 8;
187
188 dirty_bits += count_dirty_bits(buf+skip, remaining);
189
190 read_bits += remaining;
191 n = 0;
192 }
193
194 if (read_bits < total_bits) { /* file truncated... */
195 fprintf(stderr, Name ": WARNING: bitmap file is not large "
196 "enough for array size %llu!\n\n",
197 (unsigned long long)info->sb.sync_size);
198 total_bits = read_bits;
199 }
200 out:
201 info->total_bits = total_bits;
202 info->dirty_bits = dirty_bits;
203 return info;
204 }
205
206 bitmap_info_t *bitmap_file_read(char *filename, int brief, struct supertype **stp)
207 {
208 int fd;
209 bitmap_info_t *info;
210 struct stat stb;
211 struct supertype *st = *stp;
212
213 if (stat(filename, &stb) < 0) {
214 fprintf(stderr, Name ": failed to find file %s: %s\n",
215 filename, strerror(errno));
216 return NULL;
217 }
218 if ((S_IFMT & stb.st_mode) == S_IFBLK) {
219 fd = open(filename, O_RDONLY);
220 if (fd < 0) {
221 fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
222 filename, strerror(errno));
223 return NULL;
224 }
225 /* block device, so we are probably after an internal bitmap */
226 if (!st) st = guess_super(fd);
227 if (!st) {
228 /* just look at device... */
229 lseek(fd, 0, 0);
230 } else if (!st->ss->locate_bitmap) {
231 fprintf(stderr, Name ": No bitmap possible with %s metadata\n",
232 st->ss->name);
233 return NULL;
234 } else
235 st->ss->locate_bitmap(st, fd);
236
237 ioctl(fd, BLKFLSBUF, 0); /* make sure we read current data */
238 *stp = st;
239 } else {
240 fd = open(filename, O_RDONLY|O_DIRECT);
241 if (fd < 0) {
242 fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
243 filename, strerror(errno));
244 return NULL;
245 }
246 }
247
248 info = bitmap_fd_read(fd, brief);
249 close(fd);
250 return info;
251 }
252
253 __u32 swapl(__u32 l)
254 {
255 char *c = (char*)&l;
256 char t= c[0];
257 c[0] = c[3];
258 c[3] = t;
259
260 t = c[1];
261 c[1] = c[2];
262 c[2] = t;
263 return l;
264 }
265 int ExamineBitmap(char *filename, int brief, struct supertype *st)
266 {
267 /*
268 * Read the bitmap file and display its contents
269 */
270
271 bitmap_super_t *sb;
272 bitmap_info_t *info;
273 int rv = 1;
274 char buf[64];
275 int swap;
276 __u32 uuid32[4];
277
278 info = bitmap_file_read(filename, brief, &st);
279 if (!info)
280 return rv;
281
282 sb = &info->sb;
283 printf(" Filename : %s\n", filename);
284 printf(" Magic : %08x\n", sb->magic);
285 if (sb->magic != BITMAP_MAGIC) {
286 fprintf(stderr, Name ": invalid bitmap magic 0x%x, the bitmap file appears to be corrupted\n", sb->magic);
287 }
288 printf(" Version : %d\n", sb->version);
289 if (sb->version < BITMAP_MAJOR_LO ||
290 sb->version > BITMAP_MAJOR_HI) {
291 fprintf(stderr, Name ": unknown bitmap version %d, either the bitmap file is corrupted or you need to upgrade your tools\n", sb->version);
292 goto free_info;
293 }
294
295 rv = 0;
296 if (st)
297 swap = st->ss->swapuuid;
298 else
299 #if __BYTE_ORDER == BIG_ENDIAN
300 swap = 0;
301 #else
302 swap = 1;
303 #endif
304 memcpy(uuid32, sb->uuid, 16);
305 if (swap)
306 printf(" UUID : %08x:%08x:%08x:%08x\n",
307 swapl(uuid32[0]),
308 swapl(uuid32[1]),
309 swapl(uuid32[2]),
310 swapl(uuid32[3]));
311 else
312 printf(" UUID : %08x:%08x:%08x:%08x\n",
313 uuid32[0],
314 uuid32[1],
315 uuid32[2],
316 uuid32[3]);
317
318 printf(" Events : %llu\n", (unsigned long long)sb->events);
319 printf(" Events Cleared : %llu\n", (unsigned long long)sb->events_cleared);
320 printf(" State : %s\n", bitmap_state(sb->state));
321 printf(" Chunksize : %s\n", human_chunksize(sb->chunksize));
322 printf(" Daemon : %ds flush period\n", sb->daemon_sleep);
323 if (sb->write_behind)
324 sprintf(buf, "Allow write behind, max %d", sb->write_behind);
325 else
326 sprintf(buf, "Normal");
327 printf(" Write Mode : %s\n", buf);
328 printf(" Sync Size : %llu%s\n", (unsigned long long)sb->sync_size/2,
329 human_size(sb->sync_size * 512));
330 if (brief)
331 goto free_info;
332 printf(" Bitmap : %llu bits (chunks), %llu dirty (%2.1f%%)\n",
333 info->total_bits, info->dirty_bits,
334 100.0 * info->dirty_bits / (info->total_bits + 1));
335 free_info:
336 free(info);
337 return rv;
338 }
339
340 int CreateBitmap(char *filename, int force, char uuid[16],
341 unsigned long chunksize, unsigned long daemon_sleep,
342 unsigned long write_behind,
343 unsigned long long array_size /* sectors */,
344 int major)
345 {
346 /*
347 * Create a bitmap file with a superblock and (optionally) a full bitmap
348 */
349
350 FILE *fp;
351 int rv = 1;
352 char block[512];
353 bitmap_super_t sb;
354 long long bytes, filesize;
355
356 if (!force && access(filename, F_OK) == 0) {
357 fprintf(stderr, Name ": bitmap file %s already exists, use --force to overwrite\n", filename);
358 return rv;
359 }
360
361 fp = fopen(filename, "w");
362 if (fp == NULL) {
363 fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
364 filename, strerror(errno));
365 return rv;
366 }
367
368 if (chunksize == UnSet) {
369 /* We don't want more than 2^21 chunks, as 2^11 fill up one
370 * 4K page (2 bytes per chunk), and 2^10 address of those
371 * fill up a 4K indexing page. 2^20 might be safer, especially
372 * on 64bit hosts, so use that.
373 */
374 chunksize = DEFAULT_BITMAP_CHUNK;
375 /* <<20 for 2^20 chunks, >>9 to convert bytes to sectors */
376 while (array_size > ((unsigned long long)chunksize << (20-9)))
377 chunksize <<= 1;
378 }
379
380 memset(&sb, 0, sizeof(sb));
381 sb.magic = BITMAP_MAGIC;
382 sb.version = major;
383 if (uuid != NULL)
384 memcpy(sb.uuid, uuid, 16);
385 sb.chunksize = chunksize;
386 sb.daemon_sleep = daemon_sleep;
387 sb.write_behind = write_behind;
388 sb.sync_size = array_size;
389
390 sb_cpu_to_le(&sb); /* convert to on-disk byte ordering */
391
392 if (fwrite(&sb, sizeof(sb), 1, fp) != 1) {
393 fprintf(stderr, Name ": failed to write superblock to bitmap file %s: %s\n", filename, strerror(errno));
394 goto out;
395 }
396
397 /* calculate the size of the bitmap and write it to disk */
398 bytes = (bitmap_bits(array_size, chunksize) + 7) / 8;
399 if (!bytes) {
400 rv = 0;
401 goto out;
402 }
403
404 filesize = bytes + sizeof(sb);
405
406 memset(block, 0xff, sizeof(block));
407
408 while (bytes > 0) {
409 if (fwrite(block, sizeof(block), 1, fp) != 1) {
410 fprintf(stderr, Name ": failed to write bitmap file %s: %s\n", filename, strerror(errno));
411 goto out;
412 }
413 bytes -= sizeof(block);
414 }
415
416 rv = 0;
417 fflush(fp);
418 /* make the file be the right size (well, to the nearest byte) */
419 if (ftruncate(fileno(fp), filesize))
420 perror("ftrunace");
421 out:
422 fclose(fp);
423 if (rv)
424 unlink(filename); /* possibly corrupted, better get rid of it */
425 return rv;
426 }
427
428 int bitmap_update_uuid(int fd, int *uuid, int swap)
429 {
430 struct bitmap_super_s bm;
431 if (lseek(fd, 0, 0) != 0)
432 return 1;
433 if (read(fd, &bm, sizeof(bm)) != sizeof(bm))
434 return 1;
435 if (bm.magic != __cpu_to_le32(BITMAP_MAGIC))
436 return 1;
437 copy_uuid(bm.uuid, uuid, swap);
438 if (lseek(fd, 0, 0) != 0)
439 return 2;
440 if (write(fd, &bm, sizeof(bm)) != sizeof(bm)) {
441 lseek(fd, 0, 0);
442 return 2;
443 }
444 lseek(fd, 0, 0);
445 return 0;
446 }