[thirdparty/mdadm.git] / bitmap.c

/*
 * mdadm - manage Linux "md" devices aka RAID arrays.
 *
 * Copyright (C) 2004 Paul Clements, SteelEye Technology, Inc.
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <sys/types.h>
#include <sys/stat.h>
#include "mdadm.h"
#include <asm/byteorder.h>

#define min(a,b) (((a) < (b)) ? (a) : (b))

inline void sb_le_to_cpu(bitmap_super_t *sb)
{
	sb->magic = __le32_to_cpu(sb->magic);
	sb->version = __le32_to_cpu(sb->version);
	/* uuid gets no translation */
	sb->events = __le64_to_cpu(sb->events);
	sb->events_cleared = __le64_to_cpu(sb->events_cleared);
	sb->state = __le32_to_cpu(sb->state);
	sb->chunksize = __le32_to_cpu(sb->chunksize);
	sb->daemon_sleep = __le32_to_cpu(sb->daemon_sleep);
	sb->sync_size = __le64_to_cpu(sb->sync_size);
}

inline void sb_cpu_to_le(bitmap_super_t *sb)
{
	sb_le_to_cpu(sb); /* these are really the same thing */
}

mapping_t bitmap_states[] = {
	{ "OK", 0 },
	{ "Out of date", 2 },
	{ NULL, -1 }
};

const char *bitmap_state(int state_num)
{
	char *state = map_num(bitmap_states, state_num);
	return state ? state : "Unknown";
}

const char *human_chunksize(unsigned long bytes)
{
	static char buf[16];
	char *suffixes[] = { "B", "KB", "MB", "GB", "TB", NULL };
	int i = 0;

	while (bytes >> 10) {
		bytes >>= 10;
		i++;
	}

	sprintf(buf, "%lu %s", bytes, suffixes[i]);

	return buf;
}

typedef struct bitmap_info_s {
	bitmap_super_t sb;
	unsigned long long total_bits;
	unsigned long long dirty_bits;
} bitmap_info_t;

/* count the dirty bits in the first num_bits of byte */
inline int count_dirty_bits_byte(char byte, int num_bits)
{
	int num = 0;

	switch (num_bits) { /* fall through... */
		case 8:	if (byte & 128) num++;
		case 7:	if (byte &  64) num++;
		case 6:	if (byte &  32) num++;
		case 5:	if (byte &  16) num++;
		case 4:	if (byte &   8) num++;
		case 3: if (byte &   4) num++;
		case 2:	if (byte &   2) num++;
		case 1:	if (byte &   1) num++;
		default: break;
	}

	return num;
}

int count_dirty_bits(char *buf, int num_bits)
{
	int i, num = 0;

	for (i=0; i < num_bits / 8; i++)
		num += count_dirty_bits_byte(buf[i], 8);

	if (num_bits % 8) /* not an even byte boundary */
		num += count_dirty_bits_byte(buf[i], num_bits % 8);

	return num;
}

/* calculate the size of the bitmap given the array size and bitmap chunksize */
unsigned long long bitmap_bits(unsigned long long array_size,
				unsigned long chunksize)
{
	return (array_size * 512 + chunksize - 1) / chunksize;
}

bitmap_info_t *bitmap_fd_read(int fd, int brief)
{
	unsigned long long total_bits = 0, read_bits = 0, dirty_bits = 0;
	bitmap_info_t *info;
	char buf[512];
	int n;

	info = malloc(sizeof(*info));
	if (info == NULL) {
		fprintf(stderr, Name ": failed to allocate %d bytes\n",
				sizeof(*info));
		return NULL;
	}

	if (read(fd, &info->sb, sizeof(info->sb)) != sizeof(info->sb)) {
		fprintf(stderr, Name ": failed to read superblock of bitmap "
			"file: %s\n", strerror(errno));
		free(info);
		return NULL;
	}

	sb_le_to_cpu(&info->sb); /* convert superblock to CPU byte ordering */
	
	if (brief || info->sb.sync_size == 0)
		goto out;

	/* read the rest of the file counting total bits and dirty bits --
	 * we stop when either:
	 * 1) we hit EOF, in which case we assume the rest of the bits (if any)
	 *    are dirty
	 * 2) we've read the full bitmap, in which case we ignore any trailing
	 *    data in the file
	 */
	total_bits = bitmap_bits(info->sb.sync_size, info->sb.chunksize);

	while ((n = read(fd, buf, sizeof(*buf))) > 0) {
		unsigned long long remaining = total_bits - read_bits;

		if (remaining > sizeof(*buf) * 8) /* we want the full buffer */
			remaining = sizeof(*buf) * 8;
		if (remaining > n * 8) /* the file is truncated */
			remaining = n * 8;
		dirty_bits += count_dirty_bits(buf, remaining);

		read_bits += remaining;
		if (read_bits >= total_bits) /* we've got what we want */
			break;
	}

	if (read_bits < total_bits) { /* file truncated... */
		fprintf(stderr, Name ": WARNING: bitmap file is not large "
			"enough for array size %llu!\n\n", info->sb.sync_size);
		total_bits = read_bits;
	}
out:
	info->total_bits = total_bits;
	info->dirty_bits = dirty_bits;
	return info;
}

bitmap_info_t *bitmap_file_read(char *filename, int brief, struct supertype *st)
{
	int fd;
	bitmap_info_t *info;
	struct stat stb;

	fd = open(filename, O_RDONLY);
	if (fd < 0) {
		fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
				filename, strerror(errno));
		return NULL;
	}
	fstat(fd, &stb);
	if ((S_IFMT & stb.st_mode) == S_IFBLK) {
		/* block device, so we are probably after an internal bitmap */
		if (!st) st = guess_super(fd);
		if (!st) {
			/* just look at device... */
			lseek(fd, 0, 0);
		} else {	
			st->ss->locate_bitmap(st, fd);
		}
	}

	info = bitmap_fd_read(fd, brief);
	close(fd);
	return info;
}

int ExamineBitmap(char *filename, int brief, struct supertype *st)
{
	/*
	 * Read the bitmap file and display its contents
	 */

	bitmap_super_t *sb;
	bitmap_info_t *info;
	int rv = 1;

	info = bitmap_file_read(filename, brief, st);
	if (!info)
		return rv;

	sb = &info->sb;
	printf("        Filename : %s\n", filename);
	printf("           Magic : %08x\n", sb->magic);
	if (sb->magic != BITMAP_MAGIC) {
		fprintf(stderr, Name ": invalid bitmap magic 0x%x, the bitmap file appears to be corrupted\n", sb->magic);
	}
	printf("         Version : %d\n", sb->version);
	if (sb->version != BITMAP_MAJOR) {
		fprintf(stderr, Name ": unknown bitmap version %d, either the bitmap file is corrupted or you need to upgrade your tools\n", sb->version);
		goto free_info;
	}

	rv = 0;
	printf("            UUID : %08x.%08x.%08x.%08x\n",
					*(__u32 *)(sb->uuid+0),
					*(__u32 *)(sb->uuid+4),
					*(__u32 *)(sb->uuid+8),
					*(__u32 *)(sb->uuid+12));
	printf("          Events : %llu\n", sb->events);
	printf("  Events Cleared : %llu\n", sb->events_cleared);
	printf("           State : %s\n", bitmap_state(sb->state));
	printf("       Chunksize : %s\n", human_chunksize(sb->chunksize));
	printf("          Daemon : %ds flush period\n", sb->daemon_sleep);
	printf("       Sync Size : %llu%s\n", sb->sync_size,
					human_size(sb->sync_size * 1024));
	if (brief)
		goto free_info;
	printf("          Bitmap : %llu bits (chunks), %llu dirty (%2.1f%%)\n",
			info->total_bits, info->dirty_bits,
			100.0 * info->dirty_bits / (info->total_bits + 1));
free_info:
	free(info);
	return rv;
}

int CreateBitmap(char *filename, int force, char uuid[16],
		unsigned long chunksize, unsigned long daemon_sleep,
		unsigned long long array_size)
{
	/*
	 * Create a bitmap file with a superblock and (optionally) a full bitmap
	 */

	FILE *fp;
	int rv = 1;
	char block[512];
	bitmap_super_t sb;
	long long bytes, filesize;

	if (!force && access(filename, F_OK) == 0) {
		fprintf(stderr, Name ": bitmap file %s already exists, use --force to overwrite\n", filename);
		return rv;
	}

	fp = fopen(filename, "w");
	if (fp == NULL) {
		fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
			filename, strerror(errno));
		return rv;
	}

	memset(&sb, 0, sizeof(sb));
	sb.magic = BITMAP_MAGIC;
	sb.version = BITMAP_MAJOR;
	if (uuid != NULL)
		memcpy(sb.uuid, uuid, 16);
	sb.chunksize = chunksize;
	sb.daemon_sleep = daemon_sleep;
	sb.sync_size = array_size;

	sb_cpu_to_le(&sb); /* convert to on-disk byte ordering */

	if (fwrite(&sb, sizeof(sb), 1, fp) != 1) {
		fprintf(stderr, Name ": failed to write superblock to bitmap file %s: %s\n", filename, strerror(errno));
		goto out;
	}

	/* calculate the size of the bitmap and write it to disk */
	bytes = (bitmap_bits(array_size, chunksize) + 7) / 8;
	if (!bytes) {
		rv = 0;
		goto out;
	}

	filesize = bytes + sizeof(sb);

	memset(block, 0xff, sizeof(block));

	while (bytes > 0) {
		if (fwrite(block, sizeof(block), 1, fp) != 1) {
			fprintf(stderr, Name ": failed to write bitmap file %s: %s\n", filename, strerror(errno));
			goto out;
		}
		bytes -= sizeof(block);
	}
	
	rv = 0;
	/* make the file be the right size (well, to the nearest byte) */
	ftruncate(fileno(fp), filesize);
out:
	fclose(fp);
	if (rv)
		unlink(filename); /* possibly corrupted, better get rid of it */
	return rv;
}
Commit	Line	Data
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
	21	#include <sys/types.h>
	22	#include <sys/stat.h>
	23	#include "mdadm.h"
	24	#include <asm/byteorder.h>
	25
	26	#define min(a,b) (((a) < (b)) ? (a) : (b))
	27
	28	inline void sb_le_to_cpu(bitmap_super_t *sb)
	29	{
	30	sb->magic = __le32_to_cpu(sb->magic);
	31	sb->version = __le32_to_cpu(sb->version);
	32	/* uuid gets no translation */
	33	sb->events = __le64_to_cpu(sb->events);
	34	sb->events_cleared = __le64_to_cpu(sb->events_cleared);
	35	sb->state = __le32_to_cpu(sb->state);
	36	sb->chunksize = __le32_to_cpu(sb->chunksize);
	37	sb->daemon_sleep = __le32_to_cpu(sb->daemon_sleep);
	38	sb->sync_size = __le64_to_cpu(sb->sync_size);
	39	}
	40
	41	inline void sb_cpu_to_le(bitmap_super_t *sb)
	42	{
	43	sb_le_to_cpu(sb); /* these are really the same thing */
	44	}
	45
	46	mapping_t bitmap_states[] = {
	47	{ "OK", 0 },
	48	{ "Out of date", 2 },
	49	{ NULL, -1 }
	50	};
	51
	52	const char *bitmap_state(int state_num)
	53	{
	54	char *state = map_num(bitmap_states, state_num);
	55	return state ? state : "Unknown";
	56	}
	57
	58	const char *human_chunksize(unsigned long bytes)
	59	{
	60	static char buf[16];
	61	char *suffixes[] = { "B", "KB", "MB", "GB", "TB", NULL };
	62	int i = 0;
	63
	64	while (bytes >> 10) {
65	bytes >>= 10;
66	i++;
67	}
68
69	sprintf(buf, "%lu %s", bytes, suffixes[i]);
70
71	return buf;
72	}
73
74	typedef struct bitmap_info_s {
75	bitmap_super_t sb;
76	unsigned long long total_bits;
77	unsigned long long dirty_bits;
78	} bitmap_info_t;
79
80	/* count the dirty bits in the first num_bits of byte */
81	inline int count_dirty_bits_byte(char byte, int num_bits)
82	{
83	int num = 0;
84
85	switch (num_bits) { /* fall through... */
86	case 8: if (byte & 128) num++;
87	case 7: if (byte & 64) num++;
88	case 6: if (byte & 32) num++;
89	case 5: if (byte & 16) num++;
90	case 4: if (byte & 8) num++;
91	case 3: if (byte & 4) num++;
92	case 2: if (byte & 2) num++;
93	case 1: if (byte & 1) num++;
94	default: break;
95	}
96
97	return num;
98	}
99
100	int count_dirty_bits(char *buf, int num_bits)
101	{
102	int i, num = 0;
103
104	for (i=0; i < num_bits / 8; i++)
105	num += count_dirty_bits_byte(buf[i], 8);
106
107	if (num_bits % 8) /* not an even byte boundary */
108	num += count_dirty_bits_byte(buf[i], num_bits % 8);
109
110	return num;
111	}
112
113	/* calculate the size of the bitmap given the array size and bitmap chunksize */
114	unsigned long long bitmap_bits(unsigned long long array_size,
115	unsigned long chunksize)
116	{
117	return (array_size * 512 + chunksize - 1) / chunksize;
118	}
119
120	bitmap_info_t *bitmap_fd_read(int fd, int brief)
121	{
122	unsigned long long total_bits = 0, read_bits = 0, dirty_bits = 0;
123	bitmap_info_t *info;
124	char buf[512];
125	int n;
126
127	info = malloc(sizeof(*info));
128	if (info == NULL) {
129	fprintf(stderr, Name ": failed to allocate %d bytes\n",
130	sizeof(*info));
131	return NULL;
132	}
133
134	if (read(fd, &info->sb, sizeof(info->sb)) != sizeof(info->sb)) {
135	fprintf(stderr, Name ": failed to read superblock of bitmap "
136	"file: %s\n", strerror(errno));
137	free(info);
138	return NULL;
139	}
140
141	sb_le_to_cpu(&info->sb); /* convert superblock to CPU byte ordering */
142
143	if (brief \|\| info->sb.sync_size == 0)
144	goto out;
145
146	/* read the rest of the file counting total bits and dirty bits --
147	* we stop when either:
148	* 1) we hit EOF, in which case we assume the rest of the bits (if any)
149	* are dirty
150	* 2) we've read the full bitmap, in which case we ignore any trailing
151	* data in the file
152	*/
153	total_bits = bitmap_bits(info->sb.sync_size, info->sb.chunksize);
154
155	while ((n = read(fd, buf, sizeof(*buf))) > 0) {
156	unsigned long long remaining = total_bits - read_bits;
157
158	if (remaining > sizeof(buf) 8) /* we want the full buffer */
159	remaining = sizeof(buf) 8;
160	if (remaining > n * 8) /* the file is truncated */
161	remaining = n * 8;
162	dirty_bits += count_dirty_bits(buf, remaining);
163
164	read_bits += remaining;
165	if (read_bits >= total_bits) /* we've got what we want */
166	break;
167	}
168
169	if (read_bits < total_bits) { /* file truncated... */
170	fprintf(stderr, Name ": WARNING: bitmap file is not large "
171	"enough for array size %llu!\n\n", info->sb.sync_size);
172	total_bits = read_bits;
173	}
174	out:
175	info->total_bits = total_bits;
176	info->dirty_bits = dirty_bits;
177	return info;
178	}
179
55935d51	180	bitmap_info_t bitmap_file_read(char filename, int brief, struct supertype *st)
c82f047c NB	181	{
	182	int fd;
	183	bitmap_info_t *info;
55935d51	184	struct stat stb;
c82f047c NB	185
	186	fd = open(filename, O_RDONLY);
	187	if (fd < 0) {
	188	fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
	189	filename, strerror(errno));
	190	return NULL;
	191	}
55935d51 NB	192	fstat(fd, &stb);
	193	if ((S_IFMT & stb.st_mode) == S_IFBLK) {
	194	/* block device, so we are probably after an internal bitmap */
	195	if (!st) st = guess_super(fd);
	196	if (!st) {
	197	/* just look at device... */
	198	lseek(fd, 0, 0);
	199	} else {
	200	st->ss->locate_bitmap(st, fd);
	201	}
	202	}
c82f047c NB	203
	204	info = bitmap_fd_read(fd, brief);
	205	close(fd);
	206	return info;
	207	}
	208
55935d51	209	int ExamineBitmap(char filename, int brief, struct supertype st)
c82f047c NB	210	{
	211	/*
	212	* Read the bitmap file and display its contents
	213	*/
	214
	215	bitmap_super_t *sb;
	216	bitmap_info_t *info;
	217	int rv = 1;
	218
55935d51	219	info = bitmap_file_read(filename, brief, st);
c82f047c NB	220	if (!info)
	221	return rv;
	222
	223	sb = &info->sb;
	224	printf(" Filename : %s\n", filename);
	225	printf(" Magic : %08x\n", sb->magic);
	226	if (sb->magic != BITMAP_MAGIC) {
	227	fprintf(stderr, Name ": invalid bitmap magic 0x%x, the bitmap file appears to be corrupted\n", sb->magic);
	228	}
	229	printf(" Version : %d\n", sb->version);
	230	if (sb->version != BITMAP_MAJOR) {
	231	fprintf(stderr, Name ": unknown bitmap version %d, either the bitmap file is corrupted or you need to upgrade your tools\n", sb->version);
	232	goto free_info;
	233	}
	234
	235	rv = 0;
	236	printf(" UUID : %08x.%08x.%08x.%08x\n",
	237	(__u32 )(sb->uuid+0),
	238	(__u32 )(sb->uuid+4),
	239	(__u32 )(sb->uuid+8),
	240	(__u32 )(sb->uuid+12));
	241	printf(" Events : %llu\n", sb->events);
	242	printf(" Events Cleared : %llu\n", sb->events_cleared);
	243	printf(" State : %s\n", bitmap_state(sb->state));
	244	printf(" Chunksize : %s\n", human_chunksize(sb->chunksize));
	245	printf(" Daemon : %ds flush period\n", sb->daemon_sleep);
	246	printf(" Sync Size : %llu%s\n", sb->sync_size,
	247	human_size(sb->sync_size * 1024));
	248	if (brief)
	249	goto free_info;
	250	printf(" Bitmap : %llu bits (chunks), %llu dirty (%2.1f%%)\n",
	251	info->total_bits, info->dirty_bits,
	252	100.0 * info->dirty_bits / (info->total_bits + 1));
	253	free_info:
	254	free(info);
	255	return rv;
	256	}
	257
	258	int CreateBitmap(char *filename, int force, char uuid[16],
	259	unsigned long chunksize, unsigned long daemon_sleep,
	260	unsigned long long array_size)
	261	{
	262	/*
	263	* Create a bitmap file with a superblock and (optionally) a full bitmap
	264	*/
	265
	266	FILE *fp;
	267	int rv = 1;
	268	char block[512];
	269	bitmap_super_t sb;
	270	long long bytes, filesize;
	271
	272	if (!force && access(filename, F_OK) == 0) {
	273	fprintf(stderr, Name ": bitmap file %s already exists, use --force to overwrite\n", filename);
	274	return rv;
	275	}
	276
	277	fp = fopen(filename, "w");
	278	if (fp == NULL) {
	279	fprintf(stderr, Name ": failed to open bitmap file %s: %s\n",
	280	filename, strerror(errno));
	281	return rv;
	282	}
	283
284	memset(&sb, 0, sizeof(sb));
285	sb.magic = BITMAP_MAGIC;
286	sb.version = BITMAP_MAJOR;
287	if (uuid != NULL)
288	memcpy(sb.uuid, uuid, 16);
289	sb.chunksize = chunksize;
290	sb.daemon_sleep = daemon_sleep;
291	sb.sync_size = array_size;
292
293	sb_cpu_to_le(&sb); /* convert to on-disk byte ordering */
294
295	if (fwrite(&sb, sizeof(sb), 1, fp) != 1) {
296	fprintf(stderr, Name ": failed to write superblock to bitmap file %s: %s\n", filename, strerror(errno));
297	goto out;
298	}
299
300	/* calculate the size of the bitmap and write it to disk */
301	bytes = (bitmap_bits(array_size, chunksize) + 7) / 8;
302	if (!bytes) {
303	rv = 0;
304	goto out;
305	}
306
307	filesize = bytes + sizeof(sb);
308
309	memset(block, 0xff, sizeof(block));
310
311	while (bytes > 0) {
312	if (fwrite(block, sizeof(block), 1, fp) != 1) {
313	fprintf(stderr, Name ": failed to write bitmap file %s: %s\n", filename, strerror(errno));
314	goto out;
315	}
316	bytes -= sizeof(block);
317	}
318
319	rv = 0;
320	/* make the file be the right size (well, to the nearest byte) */
321	ftruncate(fileno(fp), filesize);
322	out:
323	fclose(fp);
324	if (rv)
325	unlink(filename); /* possibly corrupted, better get rid of it */
326	return rv;
327	}