[thirdparty/mdadm.git] / sysfs.c

/*
 * sysfs - extract md related information from sysfs.  Part of:
 * mdadm - manage Linux "md" devices aka RAID arrays.
 *
 * Copyright (C) 2006 Neil Brown <neilb@suse.de>
 *
 *
 *    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
 *
 *    Author: Neil Brown
 *    Email: <neilb@suse.de>
 */

#include	"mdadm.h"
#include	<dirent.h>

int load_sys(char *path, char *buf)
{
	int fd = open(path, O_RDONLY);
	int n;
	if (fd < 0)
		return -1;
	n = read(fd, buf, 1024);
	close(fd);
	if (n <=0 || n >= 1024)
		return -1;
	buf[n] = 0;
	if (buf[n-1] == '\n')
		buf[n-1] = 0;
	return 0;
}

void sysfs_free(struct sysarray *sra)
{
	if (!sra)
		return;
	while (sra->devs) {
		struct sysdev *d = sra->devs;
		sra->devs = d->next;
		free(d);
	}
	free(sra);
}

struct sysarray *sysfs_read(int fd, int devnum, unsigned long options)
{
	/* Longest possible name in sysfs, mounted at /sys, is
	 *  /sys/block/md_dXXX/md/dev-XXXXX/block/dev
	 *  /sys/block/md_dXXX/md/metadata_version
	 * which is about 41 characters.  50 should do for now
	 */
	char fname[50];
	char buf[1024];
	char *base;
	char *dbase;
	struct sysarray *sra;
	struct sysdev *dev;
	DIR *dir;
	struct dirent *de;

	sra = malloc(sizeof(*sra));
	if (sra == NULL)
		return sra;

	if (fd >= 0) {
		struct stat stb;
		if (fstat(fd, &stb)) return NULL;
		if (major(stb.st_rdev)==9)
			sprintf(sra->name, "md%d", minor(stb.st_rdev));
		else
			sprintf(sra->name, "md_d%d",
				minor(stb.st_rdev)>>MdpMinorShift);
	} else {
		if (devnum >= 0)
			sprintf(sra->name, "md%d", devnum);
		else
			sprintf(sra->name, "md_d%d",
				-1-devnum);
	}
	sprintf(fname, "/sys/block/%s/md/", sra->name);
	base = fname + strlen(fname);

	sra->devs = NULL;
	if (options & GET_VERSION) {
		strcpy(base, "metadata_version");
		if (load_sys(fname, buf))
			goto abort;
		if (strncmp(buf, "none", 4) == 0)
			sra->major_version = sra->minor_version = -1;
		else
			sscanf(buf, "%d.%d",
			       &sra->major_version, &sra->minor_version);
	}
	if (options & GET_LEVEL) {
		strcpy(base, "level");
		if (load_sys(fname, buf))
			goto abort;
		sra->level = map_name(pers, buf);
	}
	if (options & GET_LAYOUT) {
		strcpy(base, "layout");
		if (load_sys(fname, buf))
			goto abort;
		sra->layout = strtoul(buf, NULL, 0);
	}
	if (options & GET_COMPONENT) {
		strcpy(base, "component_size");
		if (load_sys(fname, buf))
			goto abort;
		sra->component_size = strtoull(buf, NULL, 0);
		/* sysfs reports "K", but we want sectors */
		sra->component_size *= 2;
	}
	if (options & GET_CHUNK) {
		strcpy(base, "chunk_size");
		if (load_sys(fname, buf))
			goto abort;
		sra->chunk = strtoul(buf, NULL, 0);
	}
	if (options & GET_CACHE) {
		strcpy(base, "stripe_cache_size");
		if (load_sys(fname, buf))
			goto abort;
		sra->cache_size = strtoul(buf, NULL, 0);
	}
	if (options & GET_MISMATCH) {
		strcpy(base, "mismatch_cnt");
		if (load_sys(fname, buf))
			goto abort;
		sra->mismatch_cnt = strtoul(buf, NULL, 0);
	}

	if (! (options & GET_DEVS))
		return sra;

	/* Get all the devices as well */
	*base = 0;
	dir = opendir(fname);
	if (!dir)
		goto abort;
	sra->spares = 0;

	while ((de = readdir(dir)) != NULL) {
		char *ep;
		if (de->d_ino == 0 ||
		    strncmp(de->d_name, "dev-", 4) != 0)
			continue;
		strcpy(base, de->d_name);
		dbase = base + strlen(base);
		*dbase++ = '/';

		dev = malloc(sizeof(*dev));
		if (!dev)
			goto abort;
		dev->next = sra->devs;
		sra->devs = dev;
		strcpy(dev->name, de->d_name);

		/* Always get slot, major, minor */
		strcpy(dbase, "slot");
		if (load_sys(fname, buf))
			goto abort;
		dev->role = strtoul(buf, &ep, 10);
		if (*ep) dev->role = -1;

		strcpy(dbase, "block/dev");
		if (load_sys(fname, buf))
			goto abort;
		sscanf(buf, "%d:%d", &dev->major, &dev->minor);

		if (options & GET_OFFSET) {
			strcpy(dbase, "offset");
			if (load_sys(fname, buf))
				goto abort;
			dev->offset = strtoull(buf, NULL, 0);
		}
		if (options & GET_SIZE) {
			strcpy(dbase, "size");
			if (load_sys(fname, buf))
				goto abort;
			dev->size = strtoull(buf, NULL, 0);
		}
		if (options & GET_STATE) {
			dev->state = 0;
			strcpy(dbase, "state");
			if (load_sys(fname, buf))
				goto abort;
			if (strstr(buf, "in_sync"))
				dev->state |= (1<<MD_DISK_SYNC);
			if (strstr(buf, "faulty"))
				dev->state |= (1<<MD_DISK_FAULTY);
			if (dev->state == 0)
				sra->spares++;
		}
		if (options & GET_ERROR) {
			strcpy(buf, "errors");
			if (load_sys(fname, buf))
				goto abort;
			dev->errors = strtoul(buf, NULL, 0);
		}
	}
	return sra;

 abort:
	sysfs_free(sra);
	return NULL;
}

unsigned long long get_component_size(int fd)
{
	/* Find out the component size of the array.
	 * We cannot trust GET_ARRAY_INFO ioctl as it's
	 * size field is only 32bits.
	 * So look in /sys/block/mdXXX/md/component_size
	 *
	 * This returns in units of sectors.
	 */
	struct stat stb;
	char fname[50];
	int n;
	if (fstat(fd, &stb)) return 0;
	if (major(stb.st_rdev) == 9)
		sprintf(fname, "/sys/block/md%d/md/component_size",
			minor(stb.st_rdev));
	else
		sprintf(fname, "/sys/block/md_d%d/md/component_size",
			minor(stb.st_rdev)>>MdpMinorShift);
	fd = open(fname, O_RDONLY);
	if (fd < 0)
		return 0;
	n = read(fd, fname, sizeof(fname));
	close(fd);
	if (n == sizeof(fname))
		return 0;
	fname[n] = 0;
	return strtoull(fname, NULL, 10) * 2;
}

int sysfs_set_str(struct sysarray *sra, struct sysdev *dev,
		  char *name, char *val)
{
	char fname[50];
	int n;
	int fd;
	sprintf(fname, "/sys/block/%s/md/%s/%s",
		sra->name, dev?dev->name:"", name);
	fd = open(fname, O_WRONLY);
	if (fd < 0)
		return -1;
	n = write(fd, val, strlen(val));
	close(fd);
	if (n != strlen(val))
		return -1;
	return 0;
}

int sysfs_set_num(struct sysarray *sra, struct sysdev *dev,
		  char *name, unsigned long long val)
{
	char valstr[50];
	sprintf(valstr, "%llu", val);
	return sysfs_set_str(sra, dev, name, valstr);
}

int sysfs_get_ll(struct sysarray *sra, struct sysdev *dev,
		       char *name, unsigned long long *val)
{
	char fname[50];
	char buf[50];
	int n;
	int fd;
	char *ep;
	sprintf(fname, "/sys/block/%s/md/%s/%s",
		sra->name, dev?dev->name:"", name);
	fd = open(fname, O_RDONLY);
	if (fd < 0)
		return -1;
	n = read(fd, buf, sizeof(buf));
	close(fd);
	if (n <= 0)
		return -1;
	buf[n] = 0;
	*val = strtoull(buf, &ep, 0);
	if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
		return -1;
	return 0;
}
Commit	Line	Data
e86c9dd6 NB	1	/*
	2	* sysfs - extract md related information from sysfs. Part of:
	3	* mdadm - manage Linux "md" devices aka RAID arrays.
	4	*
	5	* Copyright (C) 2006 Neil Brown <neilb@suse.de>
	6	*
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	21	*
	22	* Author: Neil Brown
	23	* Email: <neilb@suse.de>
	24	*/
	25
	26	#include "mdadm.h"
	27	#include <dirent.h>
	28
	29	int load_sys(char path, char buf)
	30	{
	31	int fd = open(path, O_RDONLY);
	32	int n;
	33	if (fd < 0)
	34	return -1;
	35	n = read(fd, buf, 1024);
	36	close(fd);
	37	if (n <=0 \|\| n >= 1024)
	38	return -1;
	39	buf[n] = 0;
	40	if (buf[n-1] == '\n')
	41	buf[n-1] = 0;
	42	return 0;
	43	}
	44
8382f19b NB	45	void sysfs_free(struct sysarray *sra)
	46	{
	47	if (!sra)
	48	return;
	49	while (sra->devs) {
	50	struct sysdev *d = sra->devs;
	51	sra->devs = d->next;
	52	free(d);
	53	}
	54	free(sra);
	55	}
	56
e86c9dd6 NB	57	struct sysarray *sysfs_read(int fd, int devnum, unsigned long options)
	58	{
	59	/* Longest possible name in sysfs, mounted at /sys, is
	60	* /sys/block/md_dXXX/md/dev-XXXXX/block/dev
	61	* /sys/block/md_dXXX/md/metadata_version
	62	* which is about 41 characters. 50 should do for now
	63	*/
	64	char fname[50];
	65	char buf[1024];
	66	char *base;
	67	char *dbase;
	68	struct sysarray *sra;
	69	struct sysdev *dev;
	70	DIR *dir;
	71	struct dirent *de;
	72
	73	sra = malloc(sizeof(*sra));
	74	if (sra == NULL)
	75	return sra;
	76
	77	if (fd >= 0) {
	78	struct stat stb;
	79	if (fstat(fd, &stb)) return NULL;
	80	if (major(stb.st_rdev)==9)
	81	sprintf(sra->name, "md%d", minor(stb.st_rdev));
	82	else
	83	sprintf(sra->name, "md_d%d",
7fa42a0b	84	minor(stb.st_rdev)>>MdpMinorShift);
e86c9dd6 NB	85	} else {
	86	if (devnum >= 0)
	87	sprintf(sra->name, "md%d", devnum);
	88	else
	89	sprintf(sra->name, "md_d%d",
	90	-1-devnum);
	91	}
	92	sprintf(fname, "/sys/block/%s/md/", sra->name);
	93	base = fname + strlen(fname);
	94
	95	sra->devs = NULL;
8382f19b NB	96	if (options & GET_VERSION) {
	97	strcpy(base, "metadata_version");
	98	if (load_sys(fname, buf))
	99	goto abort;
	100	if (strncmp(buf, "none", 4) == 0)
	101	sra->major_version = sra->minor_version = -1;
	102	else
	103	sscanf(buf, "%d.%d",
	104	&sra->major_version, &sra->minor_version);
	105	}
e86c9dd6 NB	106	if (options & GET_LEVEL) {
	107	strcpy(base, "level");
	108	if (load_sys(fname, buf))
	109	goto abort;
	110	sra->level = map_name(pers, buf);
	111	}
	112	if (options & GET_LAYOUT) {
	113	strcpy(base, "layout");
	114	if (load_sys(fname, buf))
	115	goto abort;
	116	sra->layout = strtoul(buf, NULL, 0);
	117	}
	118	if (options & GET_COMPONENT) {
	119	strcpy(base, "component_size");
	120	if (load_sys(fname, buf))
	121	goto abort;
	122	sra->component_size = strtoull(buf, NULL, 0);
353632d9 NB	123	/* sysfs reports "K", but we want sectors */
353632d9 NB	124	sra->component_size *= 2;
e86c9dd6 NB	125	}
	126	if (options & GET_CHUNK) {
	127	strcpy(base, "chunk_size");
	128	if (load_sys(fname, buf))
	129	goto abort;
	130	sra->chunk = strtoul(buf, NULL, 0);
	131	}
758d3a8e NB	132	if (options & GET_CACHE) {
	133	strcpy(base, "stripe_cache_size");
	134	if (load_sys(fname, buf))
	135	goto abort;
	136	sra->cache_size = strtoul(buf, NULL, 0);
	137	}
37dfc3d6 NB	138	if (options & GET_MISMATCH) {
	139	strcpy(base, "mismatch_cnt");
	140	if (load_sys(fname, buf))
	141	goto abort;
	142	sra->mismatch_cnt = strtoul(buf, NULL, 0);
	143	}
e86c9dd6 NB	144
	145	if (! (options & GET_DEVS))
	146	return sra;
	147
	148	/* Get all the devices as well */
	149	*base = 0;
	150	dir = opendir(fname);
	151	if (!dir)
	152	goto abort;
	153	sra->spares = 0;
	154
	155	while ((de = readdir(dir)) != NULL) {
	156	char *ep;
	157	if (de->d_ino == 0 \|\|
	158	strncmp(de->d_name, "dev-", 4) != 0)
	159	continue;
	160	strcpy(base, de->d_name);
	161	dbase = base + strlen(base);
	162	*dbase++ = '/';
	163
	164	dev = malloc(sizeof(*dev));
	165	if (!dev)
	166	goto abort;
	167	dev->next = sra->devs;
	168	sra->devs = dev;
8382f19b	169	strcpy(dev->name, de->d_name);
e86c9dd6 NB	170
	171	/* Always get slot, major, minor */
	172	strcpy(dbase, "slot");
	173	if (load_sys(fname, buf))
	174	goto abort;
	175	dev->role = strtoul(buf, &ep, 10);
	176	if (*ep) dev->role = -1;
	177
	178	strcpy(dbase, "block/dev");
	179	if (load_sys(fname, buf))
	180	goto abort;
	181	sscanf(buf, "%d:%d", &dev->major, &dev->minor);
	182
	183	if (options & GET_OFFSET) {
	184	strcpy(dbase, "offset");
	185	if (load_sys(fname, buf))
	186	goto abort;
	187	dev->offset = strtoull(buf, NULL, 0);
	188	}
	189	if (options & GET_SIZE) {
	190	strcpy(dbase, "size");
	191	if (load_sys(fname, buf))
	192	goto abort;
	193	dev->size = strtoull(buf, NULL, 0);
	194	}
	195	if (options & GET_STATE) {
	196	dev->state = 0;
	197	strcpy(dbase, "state");
	198	if (load_sys(fname, buf))
	199	goto abort;
	200	if (strstr(buf, "in_sync"))
	201	dev->state \|= (1<<MD_DISK_SYNC);
	202	if (strstr(buf, "faulty"))
	203	dev->state \|= (1<<MD_DISK_FAULTY);
	204	if (dev->state == 0)
	205	sra->spares++;
	206	}
	207	if (options & GET_ERROR) {
	208	strcpy(buf, "errors");
	209	if (load_sys(fname, buf))
	210	goto abort;
	211	dev->errors = strtoul(buf, NULL, 0);
	212	}
	213	}
	214	return sra;
	215
	216	abort:
8382f19b	217	sysfs_free(sra);
e86c9dd6 NB	218	return NULL;
	219	}
	220
	221	unsigned long long get_component_size(int fd)
	222	{
	223	/* Find out the component size of the array.
	224	* We cannot trust GET_ARRAY_INFO ioctl as it's
	225	* size field is only 32bits.
	226	* So look in /sys/block/mdXXX/md/component_size
353632d9	227	*
8686f3ed	228	* This returns in units of sectors.
e86c9dd6 NB	229	*/
	230	struct stat stb;
	231	char fname[50];
	232	int n;
	233	if (fstat(fd, &stb)) return 0;
	234	if (major(stb.st_rdev) == 9)
	235	sprintf(fname, "/sys/block/md%d/md/component_size",
	236	minor(stb.st_rdev));
	237	else
	238	sprintf(fname, "/sys/block/md_d%d/md/component_size",
7fa42a0b	239	minor(stb.st_rdev)>>MdpMinorShift);
e86c9dd6 NB	240	fd = open(fname, O_RDONLY);
	241	if (fd < 0)
	242	return 0;
	243	n = read(fd, fname, sizeof(fname));
	244	close(fd);
	245	if (n == sizeof(fname))
	246	return 0;
	247	fname[n] = 0;
8686f3ed	248	return strtoull(fname, NULL, 10) * 2;
e86c9dd6 NB	249	}
	250
	251	int sysfs_set_str(struct sysarray sra, struct sysdev dev,
	252	char name, char val)
	253	{
	254	char fname[50];
	255	int n;
	256	int fd;
	257	sprintf(fname, "/sys/block/%s/md/%s/%s",
	258	sra->name, dev?dev->name:"", name);
	259	fd = open(fname, O_WRONLY);
	260	if (fd < 0)
	261	return -1;
	262	n = write(fd, val, strlen(val));
	263	close(fd);
	264	if (n != strlen(val))
	265	return -1;
	266	return 0;
	267	}
	268
	269	int sysfs_set_num(struct sysarray sra, struct sysdev dev,
	270	char *name, unsigned long long val)
	271	{
	272	char valstr[50];
	273	sprintf(valstr, "%llu", val);
	274	return sysfs_set_str(sra, dev, name, valstr);
	275	}
	276
	277	int sysfs_get_ll(struct sysarray sra, struct sysdev dev,
	278	char name, unsigned long long val)
	279	{
	280	char fname[50];
	281	char buf[50];
	282	int n;
	283	int fd;
	284	char *ep;
	285	sprintf(fname, "/sys/block/%s/md/%s/%s",
	286	sra->name, dev?dev->name:"", name);
	287	fd = open(fname, O_RDONLY);
	288	if (fd < 0)
	289	return -1;
	290	n = read(fd, buf, sizeof(buf));
	291	close(fd);
	292	if (n <= 0)
	293	return -1;
	294	buf[n] = 0;
	295	*val = strtoull(buf, &ep, 0);
	296	if (ep == buf \|\| (ep != 0 && ep != '\n' && *ep != ' '))
	297	return -1;
	298	return 0;
	299	}