2 * mdadm - manage Linux "md" devices aka RAID arrays.
4 * Copyright (C) 2004 Paul Clements, SteelEye Technology, Inc.
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.
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.
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
23 static inline void sb_le_to_cpu(bitmap_super_t *sb)
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 sb->nodes = __le32_to_cpu(sb->nodes);
36 sb->sectors_reserved = __le32_to_cpu(sb->sectors_reserved);
39 static inline void sb_cpu_to_le(bitmap_super_t *sb)
41 sb_le_to_cpu(sb); /* these are really the same thing */
44 mapping_t bitmap_states[] = {
50 const char *bitmap_state(int state_num)
52 char *state = map_num(bitmap_states, state_num);
53 return state ? state : "Unknown";
56 const char *human_chunksize(unsigned long bytes)
59 char *suffixes[] = { "B", "KB", "MB", "GB", "TB", NULL };
67 snprintf(buf, sizeof(buf), "%lu %s", bytes, suffixes[i]);
72 typedef struct bitmap_info_s {
74 unsigned long long total_bits;
75 unsigned long long dirty_bits;
78 /* count the dirty bits in the first num_bits of byte */
79 static inline int count_dirty_bits_byte(char byte, int num_bits)
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++;
98 int count_dirty_bits(char *buf, int num_bits)
102 for (i = 0; i < num_bits / 8; i++)
103 num += count_dirty_bits_byte(buf[i], 8);
105 if (num_bits % 8) /* not an even byte boundary */
106 num += count_dirty_bits_byte(buf[i], num_bits % 8);
111 /* calculate the size of the bitmap given the array size and bitmap chunksize */
112 unsigned long long bitmap_bits(unsigned long long array_size,
113 unsigned long chunksize)
115 return (array_size * 512 + chunksize - 1) / chunksize;
118 unsigned long bitmap_sectors(struct bitmap_super_s *bsb)
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;
126 bitmap_info_t *bitmap_fd_read(int fd, int brief)
128 /* Note: fd might be open O_DIRECT, so we must be
129 * careful to align reads properly
131 unsigned long long total_bits = 0, read_bits = 0, dirty_bits = 0;
134 unsigned int n, skip;
136 if (posix_memalign(&buf, 4096, 8192) != 0) {
137 pr_err("failed to allocate 8192 bytes\n");
140 n = read(fd, buf, 8192);
142 info = xmalloc(sizeof(*info));
144 if (n < sizeof(info->sb)) {
145 pr_err("failed to read superblock of bitmap file: %s\n", strerror(errno));
150 memcpy(&info->sb, buf, sizeof(info->sb));
151 skip = sizeof(info->sb);
153 sb_le_to_cpu(&info->sb); /* convert superblock to CPU byte ordering */
155 if (brief || info->sb.sync_size == 0 || info->sb.chunksize == 0)
158 /* read the rest of the file counting total bits and dirty bits --
159 * we stop when either:
160 * 1) we hit EOF, in which case we assume the rest of the bits (if any)
162 * 2) we've read the full bitmap, in which case we ignore any trailing
165 total_bits = bitmap_bits(info->sb.sync_size, info->sb.chunksize);
167 while(read_bits < total_bits) {
168 unsigned long long remaining = total_bits - read_bits;
171 n = read(fd, buf, 8192);
176 if (remaining > (n-skip) * 8) /* we want the full buffer */
177 remaining = (n-skip) * 8;
179 dirty_bits += count_dirty_bits(buf+skip, remaining);
181 read_bits += remaining;
185 if (read_bits < total_bits) { /* file truncated... */
186 pr_err("WARNING: bitmap file is not large enough for array size %llu!\n\n",
187 (unsigned long long)info->sb.sync_size);
188 total_bits = read_bits;
192 info->total_bits = total_bits;
193 info->dirty_bits = dirty_bits;
197 int bitmap_file_open(char *filename, struct supertype **stp)
201 struct supertype *st = *stp;
203 if (stat(filename, &stb) < 0) {
204 pr_err("failed to find file %s: %s\n",
205 filename, strerror(errno));
208 if ((S_IFMT & stb.st_mode) == S_IFBLK) {
209 fd = open(filename, O_RDONLY|O_DIRECT);
211 pr_err("failed to open bitmap file %s: %s\n",
212 filename, strerror(errno));
215 /* block device, so we are probably after an internal bitmap */
216 if (!st) st = guess_super(fd);
218 /* just look at device... */
220 } else if (!st->ss->locate_bitmap) {
221 pr_err("No bitmap possible with %s metadata\n",
225 if (st->ss->locate_bitmap(st, fd)) {
226 pr_err("%s doesn't have bitmap\n", filename);
233 fd = open(filename, O_RDONLY|O_DIRECT);
235 pr_err("failed to open bitmap file %s: %s\n",
236 filename, strerror(errno));
256 int ExamineBitmap(char *filename, int brief, struct supertype *st)
259 * Read the bitmap file and display its contents
270 fd = bitmap_file_open(filename, &st);
274 info = bitmap_fd_read(fd, brief);
278 if (sb->magic != BITMAP_MAGIC && md_get_version(fd) > 0) {
279 pr_err("This is an md array. To view a bitmap you need to examine\n");
280 pr_err("a member device, not the array.\n");
281 pr_err("Reporting bitmap that would be used if this array were used\n");
282 pr_err("as a member of some other array\n");
285 printf(" Filename : %s\n", filename);
286 printf(" Magic : %08x\n", sb->magic);
287 if (sb->magic != BITMAP_MAGIC) {
288 pr_err("invalid bitmap magic 0x%x, the bitmap file appears\n",
290 pr_err("to be corrupted or missing.\n");
292 printf(" Version : %d\n", sb->version);
293 if (sb->version < BITMAP_MAJOR_LO ||
294 sb->version > BITMAP_MAJOR_CLUSTERED) {
295 pr_err("unknown bitmap version %d, either the bitmap file\n",
297 pr_err("is corrupted or you need to upgrade your tools\n");
303 swap = st->ss->swapuuid;
305 #if __BYTE_ORDER == BIG_ENDIAN
310 memcpy(uuid32, sb->uuid, 16);
312 printf(" UUID : %08x:%08x:%08x:%08x\n",
318 printf(" UUID : %08x:%08x:%08x:%08x\n",
324 if (sb->nodes == 0) {
325 printf(" Events : %llu\n", (unsigned long long)sb->events);
326 printf(" Events Cleared : %llu\n", (unsigned long long)sb->events_cleared);
327 printf(" State : %s\n", bitmap_state(sb->state));
331 printf(" Chunksize : %s\n", human_chunksize(sb->chunksize));
332 printf(" Daemon : %ds flush period\n", sb->daemon_sleep);
333 if (sb->write_behind)
334 sprintf(buf, "Allow write behind, max %d", sb->write_behind);
336 sprintf(buf, "Normal");
337 printf(" Write Mode : %s\n", buf);
338 printf(" Sync Size : %llu%s\n", (unsigned long long)sb->sync_size/2,
339 human_size(sb->sync_size * 512));
341 if (sb->nodes == 0) {
344 printf(" Bitmap : %llu bits (chunks), %llu dirty (%2.1f%%)\n",
345 info->total_bits, info->dirty_bits,
346 100.0 * info->dirty_bits / (info->total_bits?:1));
348 printf(" Cluster nodes : %d\n", sb->nodes);
349 printf(" Cluster name : %-64s\n", sb->cluster_name);
350 for (i = 0; i < (int)sb->nodes; i++) {
353 info = bitmap_fd_read(fd, brief);
356 if (sb->magic != BITMAP_MAGIC)
357 pr_err("invalid bitmap magic 0x%x, the bitmap file appears to be corrupted\n", sb->magic);
359 printf(" Node Slot : %d\n", i);
360 printf(" Events : %llu\n",
361 (unsigned long long)sb->events);
362 printf(" Events Cleared : %llu\n",
363 (unsigned long long)sb->events_cleared);
364 printf(" State : %s\n", bitmap_state(sb->state));
367 printf(" Bitmap : %llu bits (chunks), %llu dirty (%2.1f%%)\n",
368 info->total_bits, info->dirty_bits,
369 100.0 * info->dirty_bits / (info->total_bits?:1));
379 int CreateBitmap(char *filename, int force, char uuid[16],
380 unsigned long chunksize, unsigned long daemon_sleep,
381 unsigned long write_behind,
382 unsigned long long array_size /* sectors */,
386 * Create a bitmap file with a superblock and (optionally) a full bitmap
393 long long bytes, filesize;
395 if (!force && access(filename, F_OK) == 0) {
396 pr_err("bitmap file %s already exists, use --force to overwrite\n", filename);
400 fp = fopen(filename, "w");
402 pr_err("failed to open bitmap file %s: %s\n",
403 filename, strerror(errno));
407 if (chunksize == UnSet) {
408 /* We don't want more than 2^21 chunks, as 2^11 fill up one
409 * 4K page (2 bytes per chunk), and 2^10 address of those
410 * fill up a 4K indexing page. 2^20 might be safer, especially
411 * on 64bit hosts, so use that.
413 chunksize = DEFAULT_BITMAP_CHUNK;
414 /* <<20 for 2^20 chunks, >>9 to convert bytes to sectors */
415 while (array_size > ((unsigned long long)chunksize << (20-9)))
419 memset(&sb, 0, sizeof(sb));
420 sb.magic = BITMAP_MAGIC;
423 memcpy(sb.uuid, uuid, 16);
424 sb.chunksize = chunksize;
425 sb.daemon_sleep = daemon_sleep;
426 sb.write_behind = write_behind;
427 sb.sync_size = array_size;
429 sb_cpu_to_le(&sb); /* convert to on-disk byte ordering */
431 if (fwrite(&sb, sizeof(sb), 1, fp) != 1) {
432 pr_err("failed to write superblock to bitmap file %s: %s\n", filename, strerror(errno));
436 /* calculate the size of the bitmap and write it to disk */
437 bytes = (bitmap_bits(array_size, chunksize) + 7) / 8;
443 filesize = bytes + sizeof(sb);
445 memset(block, 0xff, sizeof(block));
448 if (fwrite(block, sizeof(block), 1, fp) != 1) {
449 pr_err("failed to write bitmap file %s: %s\n", filename, strerror(errno));
452 bytes -= sizeof(block);
457 /* make the file be the right size (well, to the nearest byte) */
458 if (ftruncate(fileno(fp), filesize))
463 unlink(filename); /* possibly corrupted, better get rid of it */
467 int bitmap_update_uuid(int fd, int *uuid, int swap)
469 struct bitmap_super_s bm;
470 if (lseek(fd, 0, 0) != 0)
472 if (read(fd, &bm, sizeof(bm)) != sizeof(bm))
474 if (bm.magic != __cpu_to_le32(BITMAP_MAGIC))
476 copy_uuid(bm.uuid, uuid, swap);
477 if (lseek(fd, 0, 0) != 0)
479 if (write(fd, &bm, sizeof(bm)) != sizeof(bm)) {