[mirror_lxc.git] / src / lxc / storage / lvm.c

/*
 * lxc: linux Container library
 *
 * (C) Copyright IBM Corp. 2007, 2008
 *
 * Authors:
 * Daniel Lezcano <daniel.lezcano at free.fr>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#define _GNU_SOURCE
#define __STDC_FORMAT_MACROS
#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/sysmacros.h>
#include <sys/wait.h>

#include "config.h"
#include "log.h"
#include "lvm.h"
#include "rsync.h"
#include "storage.h"
#include "storage_utils.h"
#include "utils.h"

#ifdef MAJOR_IN_MKDEV
#include <sys/mkdev.h>
#endif

lxc_log_define(lvm, lxc);

struct lvcreate_args {
	const char *size;
	const char *vg;
	const char *lv;
	const char *thinpool;

	/* snapshot specific arguments */
	const char *source_lv;
};

static int lvm_destroy_exec_wrapper(void *data)
{
	struct lvcreate_args *args = data;

	(void)setenv("LVM_SUPPRESS_FD_WARNINGS", "1", 1);
	execlp("lvremove", "lvremove", "-f", args->lv, (char *)NULL);

	return -1;
}

static int lvm_create_exec_wrapper(void *data)
{
	struct lvcreate_args *args = data;

	(void)setenv("LVM_SUPPRESS_FD_WARNINGS", "1", 1);
	if (args->thinpool)
		execlp("lvcreate", "lvcreate", "--thinpool", args->thinpool,
		       "-V", args->size, args->vg, "-n", args->lv,
		       (char *)NULL);
	else
		execlp("lvcreate", "lvcreate", "-L", args->size, args->vg, "-n",
		       args->lv, (char *)NULL);

	return -1;
}

static int lvm_snapshot_exec_wrapper(void *data)
{
	struct lvcreate_args *args = data;

	(void)setenv("LVM_SUPPRESS_FD_WARNINGS", "1", 1);
	if (args->thinpool)
		execlp("lvcreate", "lvcreate", "-s", "-n", args->lv,
		       args->source_lv, (char *)NULL);
	else
		execlp("lvcreate", "lvcreate", "-s", "-L", args->size, "-n",
		       args->lv, args->source_lv, (char *)NULL);

	return -1;
}

/* The path must be "/dev/<vg>/<lv>". The volume group <vg> must be an existing
 * volume group, and the logical volume <lv> must not yet exist.
 * This function will attempt to create "/dev/<vg>/<lv> of size <size>. If
 * thinpool is specified, we'll check for it's existence and if it's a valid
 * thin pool, and if so, we'll create the requested logical volume from that
 * thin pool.
 */
static int do_lvm_create(const char *path, uint64_t size, const char *thinpool)
{
	int len, ret;
	char *pathdup, *vg, *lv;
	char cmd_output[MAXPATHLEN];
	char sz[24];
	char *tp = NULL;
	struct lvcreate_args cmd_args = {0};

	ret = snprintf(sz, 24, "%" PRIu64 "b", size);
	if (ret < 0 || ret >= 24) {
		ERROR("Failed to create string: %d", ret);
		return -1;
	}

	pathdup = strdup(path);
	if (!pathdup) {
		ERROR("Failed to duplicate string \"%s\"", path);
		return -1;
	}

	lv = strrchr(pathdup, '/');
	if (!lv) {
		ERROR("Failed to detect \"/\" in string \"%s\"", pathdup);
		free(pathdup);
		return -1;
	}
	*lv = '\0';
	lv++;
	TRACE("Parsed logical volume \"%s\"", lv);

	vg = strrchr(pathdup, '/');
	if (!vg) {
		ERROR("Failed to detect \"/\" in string \"%s\"", pathdup);
		free(pathdup);
		return -1;
	}
	vg++;
	TRACE("Parsed volume group \"%s\"", vg);

	if (thinpool) {
		len = strlen(pathdup) + strlen(thinpool) + 2;
		tp = alloca(len);

		ret = snprintf(tp, len, "%s/%s", pathdup, thinpool);
		if (ret < 0 || ret >= len) {
			ERROR("Failed to create string: %d", ret);
			free(pathdup);
			return -1;
		}

		ret = lvm_is_thin_pool(tp);
		TRACE("got %d for thin pool at path: %s", ret, tp);
		if (ret < 0) {
			ERROR("Failed to detect whether \"%s\" is a thinpool", tp);
			free(pathdup);
			return -1;
		} else if (!ret) {
			TRACE("Detected that \"%s\" is not a thinpool", tp);
			tp = NULL;
		} else {
			TRACE("Detected \"%s\" is a thinpool", tp);
		}
	}

	cmd_args.thinpool = tp;
	cmd_args.vg = vg;
	cmd_args.lv = lv;
	cmd_args.size = sz;
	TRACE("Creating new lvm storage volume \"%s\" on volume group \"%s\" "
	      "of size \"%s\"", lv, vg, sz);
	ret = run_command(cmd_output, sizeof(cmd_output),
			  lvm_create_exec_wrapper, (void *)&cmd_args);
	if (ret < 0) {
		ERROR("Failed to create logical volume \"%s\": %s", lv,
		      cmd_output);
		free(pathdup);
		return -1;
	}
	TRACE("Created new lvm storage volume \"%s\" on volume group \"%s\" "
	      "of size \"%s\"", lv, vg, sz);

	free(pathdup);
	return ret;
}

/* Look at "/sys/dev/block/maj:min/dm/uuid". If it contains the hardcoded LVM
 * prefix "LVM-" then this is an lvm2 LV.
 */
bool lvm_detect(const char *path)
{
	int fd;
	ssize_t ret;
	struct stat statbuf;
	char devp[MAXPATHLEN], buf[4];

	if (!strncmp(path, "lvm:", 4))
		return true;

	ret = stat(path, &statbuf);
	if (ret < 0)
		return false;

	if (!S_ISBLK(statbuf.st_mode))
		return false;

	ret = snprintf(devp, MAXPATHLEN, "/sys/dev/block/%d:%d/dm/uuid",
		       major(statbuf.st_rdev), minor(statbuf.st_rdev));
	if (ret < 0 || ret >= MAXPATHLEN) {
		ERROR("Failed to create string");
		return false;
	}

	fd = open(devp, O_RDONLY);
	if (fd < 0)
		return false;

	ret = read(fd, buf, sizeof(buf));
	close(fd);
	if (ret != sizeof(buf))
		return false;

	if (strncmp(buf, "LVM-", 4))
		return false;

	return true;
}

int lvm_mount(struct lxc_storage *bdev)
{
	char *src;

	if (strcmp(bdev->type, "lvm"))
		return -22;

	if (!bdev->src || !bdev->dest)
		return -22;

	src = lxc_storage_get_path(bdev->src, bdev->type);

	/* If we might pass in data sometime, then we'll have to enrich
	 * mount_unknown_fs().
	 */
	return mount_unknown_fs(src, bdev->dest, bdev->mntopts);
}

int lvm_umount(struct lxc_storage *bdev)
{
	if (strcmp(bdev->type, "lvm"))
		return -22;

	if (!bdev->src || !bdev->dest)
		return -22;

	return umount(bdev->dest);
}

int lvm_compare_lv_attr(const char *path, int pos, const char expected)
{
	struct lxc_popen_FILE *f;
	int ret, status;
	size_t len;
	char *cmd;
	char output[12];
	int start = 0;
	const char *lvscmd = "lvs --unbuffered --noheadings -o lv_attr %s 2>/dev/null";

	len = strlen(lvscmd) + strlen(path) + 1;
	cmd = alloca(len);

	ret = snprintf(cmd, len, lvscmd, path);
	if (ret < 0 || (size_t)ret >= len)
		return -1;

	f = lxc_popen(cmd);
	if (!f) {
		SYSERROR("popen failed");
		return -1;
	}

	ret = 0;
	if (!fgets(output, 12, f->f))
		ret = 1;

	status = lxc_pclose(f);
	/* Assume either vg or lvs do not exist, default comparison to false. */
	if (ret || WEXITSTATUS(status))
		return 0;

	len = strlen(output);
	while (start < len && output[start] == ' ')
		start++;

	if (start + pos < len && output[start + pos] == expected)
		return 1;

	return 0;
}

int lvm_is_thin_volume(const char *path)
{
	return lvm_compare_lv_attr(path, 6, 't');
}

int lvm_is_thin_pool(const char *path)
{
	return lvm_compare_lv_attr(path, 0, 't');
}

int lvm_snapshot(const char *orig, const char *path, uint64_t size)
{
	int ret;
	char *pathdup, *lv;
	char sz[24];
	char cmd_output[MAXPATHLEN];
	struct lvcreate_args cmd_args = {0};

	ret = snprintf(sz, 24, "%" PRIu64 "b", size);
	if (ret < 0 || ret >= 24) {
		ERROR("Failed to create string");
		return -1;
	}

	pathdup = strdup(path);
	if (!pathdup) {
		ERROR("Failed to duplicate string \"%s\"", path);
		return -1;
	}

	lv = strrchr(pathdup, '/');
	if (!lv) {
		ERROR("Failed to detect \"/\" in string \"%s\"", pathdup);
		free(pathdup);
		return -1;
	}
	*lv = '\0';
	lv++;
	TRACE("Parsed logical volume \"%s\"", lv);

	/* Check if the original logical volume is backed by a thinpool, in
	 * which case we cannot specify a size that's different from the
	 * original size.
	 */
	ret = lvm_is_thin_volume(orig);
	if (ret < 0) {
		free(pathdup);
		return -1;
	} else if (ret) {
		cmd_args.thinpool = orig;
	}

	cmd_args.lv = lv;
	cmd_args.source_lv = orig;
	cmd_args.size = sz;
	TRACE("Creating new lvm snapshot \"%s\" of \"%s\" with size \"%s\"", lv,
	      orig, sz);
	ret = run_command(cmd_output, sizeof(cmd_output),
			  lvm_snapshot_exec_wrapper, (void *)&cmd_args);
	if (ret < 0) {
		ERROR("Failed to create logical volume \"%s\": %s", orig,
		      cmd_output);
		free(pathdup);
		return -1;
	}

	free(pathdup);
	return 0;
}

int lvm_clonepaths(struct lxc_storage *orig, struct lxc_storage *new,
		   const char *oldname, const char *cname, const char *oldpath,
		   const char *lxcpath, int snap, uint64_t newsize,
		   struct lxc_conf *conf)
{
	int len, ret;
	const char *vg;

	if (!orig->src || !orig->dest)
		return -1;

	if (strcmp(orig->type, "lvm") && snap) {
		ERROR("LVM snapshot from \"%s\" storage driver is not supported",
		      orig->type);
		return -1;
	}

	if (strcmp(orig->type, "lvm")) {
		vg = lxc_global_config_value("lxc.bdev.lvm.vg");
		new->src = lxc_string_join(
		    "/",
		    (const char *[]){"lvm:", "dev", vg, cname, NULL},
		    false);
	} else {
		char *dup, *slider, *src;

		src = lxc_storage_get_path(orig->src, orig->type);

		dup = strdup(src);
		if (!dup) {
			ERROR("Failed to duplicate string \"%s\"", src);
			return -1;
		}

		slider = strrchr(dup, '/');
		if (!slider) {
			ERROR("Failed to detect \"/\" in string \"%s\"", dup);
			free(dup);
			return -1;
		}
		*slider = '\0';
		slider = dup;

		new->src = lxc_string_join(
		    "/",
		    (const char *[]){"lvm:", *slider == '/' ? ++slider : slider,
				     cname, NULL},
		    false);
		free(dup);
	}
	if (!new->src) {
		ERROR("Failed to create string");
		return -1;
	}

	if (orig->mntopts) {
		new->mntopts = strdup(orig->mntopts);
		if (!new->mntopts) {
			ERROR("Failed to duplicate string \"%s\"", orig->mntopts);
			return -1;
		}
	}

	len = strlen(lxcpath) + strlen(cname) + strlen("rootfs") + 3;
	new->dest = malloc(len);
	if (!new->dest) {
		ERROR("Failed to allocate memory");
		return -1;
	}

	ret = snprintf(new->dest, len, "%s/%s/rootfs", lxcpath, cname);
	if (ret < 0 || ret >= len) {
		ERROR("Failed to create string");
		return -1;
	}

	ret = mkdir_p(new->dest, 0755);
	if (ret < 0) {
		SYSERROR("Failed to create directory \"%s\"", new->dest);
		return -1;
	}

	return 0;
}

bool lvm_create_clone(struct lxc_conf *conf, struct lxc_storage *orig,
		      struct lxc_storage *new, uint64_t newsize)
{
	char *src;
	const char *thinpool;
	int ret;
	struct rsync_data data;
	char *cmd_args[2];
	char cmd_output[MAXPATHLEN] = {0};
	char fstype[100] = "ext4";
	uint64_t size = newsize;

	if (is_blktype(orig)) {
		/* detect size */
		if (!newsize && blk_getsize(orig, &size) < 0) {
			ERROR("Failed to detect size of logical volume \"%s\"",
			      orig->src);
			return -1;
		}

		/* detect filesystem */
		if (detect_fs(orig, fstype, 100) < 0) {
			INFO("Failed to detect filesystem type for \"%s\"", orig->src);
			return -1;
		}
	} else if (!newsize) {
			size = DEFAULT_FS_SIZE;
	}

	src = lxc_storage_get_path(new->src, "lvm");
	thinpool = lxc_global_config_value("lxc.bdev.lvm.thin_pool");

	ret = do_lvm_create(src, size, thinpool);
	if (ret < 0) {
		ERROR("Failed to create lvm storage volume \"%s\"", src);
		return -1;
	}

	cmd_args[0] = fstype;
	cmd_args[1] = src;
	ret = run_command(cmd_output, sizeof(cmd_output),
			do_mkfs_exec_wrapper, (void *)cmd_args);
	if (ret < 0) {
		ERROR("Failed to create new filesystem \"%s\" for lvm storage "
		      "volume \"%s\": %s", fstype, src, cmd_output);
		return -1;
	}

	data.orig = orig;
	data.new = new;
	ret = run_command(cmd_output, sizeof(cmd_output),
			  lxc_storage_rsync_exec_wrapper, (void *)&data);
	if (ret < 0) {
		ERROR("Failed to rsync from \"%s\" to \"%s\"", orig->dest,
		      new->dest);
		return false;
	}

	TRACE("Created lvm storage volume \"%s\"", new->dest);
	return true;
}

bool lvm_create_snapshot(struct lxc_conf *conf, struct lxc_storage *orig,
			 struct lxc_storage *new, uint64_t newsize)
{
	int ret;
	char *newsrc, *origsrc;
	uint64_t size = newsize;

	if (is_blktype(orig)) {
		if (!newsize && blk_getsize(orig, &size) < 0) {
			ERROR("Failed to detect size of logical volume \"%s\"",
			      orig->src);
			return -1;
		}
	} else if (!newsize) {
			size = DEFAULT_FS_SIZE;
	}

	origsrc = lxc_storage_get_path(orig->src, "lvm");
	newsrc = lxc_storage_get_path(new->src, "lvm");

	ret = lvm_snapshot(origsrc, newsrc, size);
	if (ret < 0) {
		ERROR("Failed to create lvm \"%s\" snapshot of \"%s\"",
		      new->src, orig->src);
		return false;
	}

	TRACE("Created lvm snapshot \"%s\" from \"%s\"", new->dest, orig->dest);
	return true;
}

int lvm_destroy(struct lxc_storage *orig)
{
	int ret;
	char cmd_output[MAXPATHLEN];
	struct lvcreate_args cmd_args = {0};

	cmd_args.lv = lxc_storage_get_path(orig->src, "lvm");
	ret = run_command(cmd_output, sizeof(cmd_output),
			  lvm_destroy_exec_wrapper, (void *)&cmd_args);
	if (ret < 0) {
		ERROR("Failed to destroy logical volume \"%s\": %s", orig->src,
		      cmd_output);
		return -1;
	}

	TRACE("Destroyed logical volume \"%s\"", orig->src);
	return 0;
}

int lvm_create(struct lxc_storage *bdev, const char *dest, const char *n,
	       struct bdev_specs *specs)
{
	const char *vg, *thinpool, *fstype, *lv = n;
	uint64_t sz;
	int ret, len;
	const char *cmd_args[2];
	char cmd_output[MAXPATHLEN];

	if (!specs)
		return -1;

	vg = specs->lvm.vg;
	if (!vg)
		vg = lxc_global_config_value("lxc.bdev.lvm.vg");

	thinpool = specs->lvm.thinpool;
	if (!thinpool)
		thinpool = lxc_global_config_value("lxc.bdev.lvm.thin_pool");

	/* /dev/$vg/$lv */
	if (specs->lvm.lv)
		lv = specs->lvm.lv;

	len = strlen(vg) + strlen(lv) + 4 + 7;
	bdev->src = malloc(len);
	if (!bdev->src) {
		ERROR("Failed to allocate memory");
		return -1;
	}

	ret = snprintf(bdev->src, len, "lvm:/dev/%s/%s", vg, lv);
	if (ret < 0 || ret >= len) {
		ERROR("Failed to create string");
		return -1;
	}

	/* size is in bytes */
	sz = specs->fssize;
	if (!sz)
		sz = DEFAULT_FS_SIZE;

	ret = do_lvm_create(bdev->src + 4, sz, thinpool);
	if (ret < 0) {
		ERROR("Error creating new logical volume \"%s\" of size "
		      "\"%" PRIu64 " bytes\"", bdev->src, sz);
		return -1;
	}

	fstype = specs->fstype;
	if (!fstype)
		fstype = DEFAULT_FSTYPE;

	cmd_args[0] = fstype;
	cmd_args[1] = lxc_storage_get_path(bdev->src, bdev->type);
	ret = run_command(cmd_output, sizeof(cmd_output), do_mkfs_exec_wrapper,
			  (void *)cmd_args);
	if (ret < 0) {
		ERROR("Failed to create new logical volume \"%s\": %s",
		      bdev->src, cmd_output);
		return -1;
	}

	bdev->dest = strdup(dest);
	if (!bdev->dest) {
		ERROR("Failed to duplicate string \"%s\"", dest);
		return -1;
	}

	ret = mkdir_p(bdev->dest, 0755);
	if (ret < 0) {
		SYSERROR("Failed to create directory \"%s\"", bdev->dest);
		return -1;
	}

	TRACE("Created new logical volume \"%s\"", bdev->dest);
	return 0;
}
Commit	Line	Data
	1	/*
	2	* lxc: linux Container library
	3	*
	4	* (C) Copyright IBM Corp. 2007, 2008
	5	*
	6	* Authors:
	7	* Daniel Lezcano <daniel.lezcano at free.fr>
	8	*
	9	* This library is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU Lesser General Public
	11	* License as published by the Free Software Foundation; either
	12	* version 2.1 of the License, or (at your option) any later version.
	13	*
	14	* This library is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* Lesser General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU Lesser General Public
	20	* License along with this library; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	22	*/
	23
	24	#define _GNU_SOURCE
	25	#define __STDC_FORMAT_MACROS
	26	#include <inttypes.h>
	27	#include <stdint.h>
	28	#include <stdio.h>
	29	#include <stdlib.h>
	30	#include <string.h>
	31	#include <unistd.h>
	32	#include <sys/sysmacros.h>
	33	#include <sys/wait.h>
	34
	35	#include "config.h"
	36	#include "log.h"
	37	#include "lvm.h"
	38	#include "rsync.h"
	39	#include "storage.h"
	40	#include "storage_utils.h"
	41	#include "utils.h"
	42
	43	#ifdef MAJOR_IN_MKDEV
	44	#include <sys/mkdev.h>
	45	#endif
	46
	47	lxc_log_define(lvm, lxc);
	48
	49	struct lvcreate_args {
	50	const char *size;
	51	const char *vg;
	52	const char *lv;
	53	const char *thinpool;
	54
	55	/* snapshot specific arguments */
	56	const char *source_lv;
	57	};
	58
	59	static int lvm_destroy_exec_wrapper(void *data)
	60	{
	61	struct lvcreate_args *args = data;
	62
	63	(void)setenv("LVM_SUPPRESS_FD_WARNINGS", "1", 1);
	64	execlp("lvremove", "lvremove", "-f", args->lv, (char *)NULL);
	65
	66	return -1;
	67	}
	68
	69	static int lvm_create_exec_wrapper(void *data)
	70	{
	71	struct lvcreate_args *args = data;
	72
	73	(void)setenv("LVM_SUPPRESS_FD_WARNINGS", "1", 1);
	74	if (args->thinpool)
	75	execlp("lvcreate", "lvcreate", "--thinpool", args->thinpool,
	76	"-V", args->size, args->vg, "-n", args->lv,
	77	(char *)NULL);
	78	else
	79	execlp("lvcreate", "lvcreate", "-L", args->size, args->vg, "-n",
	80	args->lv, (char *)NULL);
	81
	82	return -1;
	83	}
	84
	85	static int lvm_snapshot_exec_wrapper(void *data)
	86	{
	87	struct lvcreate_args *args = data;
	88
	89	(void)setenv("LVM_SUPPRESS_FD_WARNINGS", "1", 1);
	90	if (args->thinpool)
	91	execlp("lvcreate", "lvcreate", "-s", "-n", args->lv,
	92	args->source_lv, (char *)NULL);
	93	else
	94	execlp("lvcreate", "lvcreate", "-s", "-L", args->size, "-n",
	95	args->lv, args->source_lv, (char *)NULL);
	96
	97	return -1;
	98	}
	99
	100	/* The path must be "/dev/<vg>/<lv>". The volume group <vg> must be an existing
	101	* volume group, and the logical volume <lv> must not yet exist.
	102	* This function will attempt to create "/dev/<vg>/<lv> of size <size>. If
	103	* thinpool is specified, we'll check for it's existence and if it's a valid
	104	* thin pool, and if so, we'll create the requested logical volume from that
	105	* thin pool.
	106	*/
	107	static int do_lvm_create(const char path, uint64_t size, const char thinpool)
	108	{
	109	int len, ret;
	110	char pathdup, vg, *lv;
	111	char cmd_output[MAXPATHLEN];
	112	char sz[24];
	113	char *tp = NULL;
	114	struct lvcreate_args cmd_args = {0};
	115
	116	ret = snprintf(sz, 24, "%" PRIu64 "b", size);
	117	if (ret < 0 \|\| ret >= 24) {
	118	ERROR("Failed to create string: %d", ret);
	119	return -1;
	120	}
	121
	122	pathdup = strdup(path);
	123	if (!pathdup) {
	124	ERROR("Failed to duplicate string \"%s\"", path);
	125	return -1;
	126	}
	127
	128	lv = strrchr(pathdup, '/');
	129	if (!lv) {
	130	ERROR("Failed to detect \"/\" in string \"%s\"", pathdup);
	131	free(pathdup);
	132	return -1;
	133	}
	134	*lv = '\0';
	135	lv++;
	136	TRACE("Parsed logical volume \"%s\"", lv);
	137
	138	vg = strrchr(pathdup, '/');
	139	if (!vg) {
	140	ERROR("Failed to detect \"/\" in string \"%s\"", pathdup);
	141	free(pathdup);
	142	return -1;
	143	}
	144	vg++;
	145	TRACE("Parsed volume group \"%s\"", vg);
	146
	147	if (thinpool) {
	148	len = strlen(pathdup) + strlen(thinpool) + 2;
	149	tp = alloca(len);
	150
	151	ret = snprintf(tp, len, "%s/%s", pathdup, thinpool);
	152	if (ret < 0 \|\| ret >= len) {
	153	ERROR("Failed to create string: %d", ret);
	154	free(pathdup);
	155	return -1;
	156	}
	157
	158	ret = lvm_is_thin_pool(tp);
	159	TRACE("got %d for thin pool at path: %s", ret, tp);
	160	if (ret < 0) {
	161	ERROR("Failed to detect whether \"%s\" is a thinpool", tp);
	162	free(pathdup);
	163	return -1;
	164	} else if (!ret) {
	165	TRACE("Detected that \"%s\" is not a thinpool", tp);
	166	tp = NULL;
	167	} else {
	168	TRACE("Detected \"%s\" is a thinpool", tp);
	169	}
	170	}
	171
	172	cmd_args.thinpool = tp;
	173	cmd_args.vg = vg;
	174	cmd_args.lv = lv;
	175	cmd_args.size = sz;
	176	TRACE("Creating new lvm storage volume \"%s\" on volume group \"%s\" "
	177	"of size \"%s\"", lv, vg, sz);
	178	ret = run_command(cmd_output, sizeof(cmd_output),
	179	lvm_create_exec_wrapper, (void *)&cmd_args);
	180	if (ret < 0) {
	181	ERROR("Failed to create logical volume \"%s\": %s", lv,
	182	cmd_output);
	183	free(pathdup);
	184	return -1;
	185	}
	186	TRACE("Created new lvm storage volume \"%s\" on volume group \"%s\" "
	187	"of size \"%s\"", lv, vg, sz);
	188
	189	free(pathdup);
	190	return ret;
	191	}
	192
	193	/* Look at "/sys/dev/block/maj:min/dm/uuid". If it contains the hardcoded LVM
	194	* prefix "LVM-" then this is an lvm2 LV.
	195	*/
	196	bool lvm_detect(const char *path)
	197	{
	198	int fd;
	199	ssize_t ret;
	200	struct stat statbuf;
	201	char devp[MAXPATHLEN], buf[4];
	202
	203	if (!strncmp(path, "lvm:", 4))
	204	return true;
	205
	206	ret = stat(path, &statbuf);
	207	if (ret < 0)
	208	return false;
	209
	210	if (!S_ISBLK(statbuf.st_mode))
	211	return false;
	212
	213	ret = snprintf(devp, MAXPATHLEN, "/sys/dev/block/%d:%d/dm/uuid",
	214	major(statbuf.st_rdev), minor(statbuf.st_rdev));
	215	if (ret < 0 \|\| ret >= MAXPATHLEN) {
	216	ERROR("Failed to create string");
	217	return false;
	218	}
	219
	220	fd = open(devp, O_RDONLY);
	221	if (fd < 0)
	222	return false;
	223
	224	ret = read(fd, buf, sizeof(buf));
	225	close(fd);
	226	if (ret != sizeof(buf))
	227	return false;
	228
	229	if (strncmp(buf, "LVM-", 4))
	230	return false;
	231
	232	return true;
	233	}
	234
	235	int lvm_mount(struct lxc_storage *bdev)
	236	{
	237	char *src;
	238
	239	if (strcmp(bdev->type, "lvm"))
	240	return -22;
	241
	242	if (!bdev->src \|\| !bdev->dest)
	243	return -22;
	244
	245	src = lxc_storage_get_path(bdev->src, bdev->type);
	246
	247	/* If we might pass in data sometime, then we'll have to enrich
	248	* mount_unknown_fs().
	249	*/
	250	return mount_unknown_fs(src, bdev->dest, bdev->mntopts);
	251	}
	252
	253	int lvm_umount(struct lxc_storage *bdev)
	254	{
	255	if (strcmp(bdev->type, "lvm"))
	256	return -22;
	257
	258	if (!bdev->src \|\| !bdev->dest)
	259	return -22;
	260
	261	return umount(bdev->dest);
	262	}
	263
	264	int lvm_compare_lv_attr(const char *path, int pos, const char expected)
	265	{
	266	struct lxc_popen_FILE *f;
	267	int ret, status;
	268	size_t len;
	269	char *cmd;
	270	char output[12];
	271	int start = 0;
	272	const char *lvscmd = "lvs --unbuffered --noheadings -o lv_attr %s 2>/dev/null";
	273
	274	len = strlen(lvscmd) + strlen(path) + 1;
	275	cmd = alloca(len);
	276
	277	ret = snprintf(cmd, len, lvscmd, path);
	278	if (ret < 0 \|\| (size_t)ret >= len)
	279	return -1;
	280
	281	f = lxc_popen(cmd);
	282	if (!f) {
	283	SYSERROR("popen failed");
	284	return -1;
	285	}
	286
	287	ret = 0;
	288	if (!fgets(output, 12, f->f))
	289	ret = 1;
	290
	291	status = lxc_pclose(f);
	292	/* Assume either vg or lvs do not exist, default comparison to false. */
	293	if (ret \|\| WEXITSTATUS(status))
	294	return 0;
	295
	296	len = strlen(output);
	297	while (start < len && output[start] == ' ')
	298	start++;
	299
	300	if (start + pos < len && output[start + pos] == expected)
	301	return 1;
	302
	303	return 0;
	304	}
	305
	306	int lvm_is_thin_volume(const char *path)
	307	{
	308	return lvm_compare_lv_attr(path, 6, 't');
	309	}
	310
	311	int lvm_is_thin_pool(const char *path)
	312	{
	313	return lvm_compare_lv_attr(path, 0, 't');
	314	}
	315
	316	int lvm_snapshot(const char orig, const char path, uint64_t size)
	317	{
	318	int ret;
	319	char pathdup, lv;
	320	char sz[24];
	321	char cmd_output[MAXPATHLEN];
	322	struct lvcreate_args cmd_args = {0};
	323
	324	ret = snprintf(sz, 24, "%" PRIu64 "b", size);
	325	if (ret < 0 \|\| ret >= 24) {
	326	ERROR("Failed to create string");
	327	return -1;
	328	}
	329
	330	pathdup = strdup(path);
	331	if (!pathdup) {
	332	ERROR("Failed to duplicate string \"%s\"", path);
	333	return -1;
	334	}
	335
	336	lv = strrchr(pathdup, '/');
	337	if (!lv) {
	338	ERROR("Failed to detect \"/\" in string \"%s\"", pathdup);
	339	free(pathdup);
	340	return -1;
	341	}
	342	*lv = '\0';
	343	lv++;
	344	TRACE("Parsed logical volume \"%s\"", lv);
	345
	346	/* Check if the original logical volume is backed by a thinpool, in
	347	* which case we cannot specify a size that's different from the
	348	* original size.
	349	*/
	350	ret = lvm_is_thin_volume(orig);
	351	if (ret < 0) {
	352	free(pathdup);
	353	return -1;
	354	} else if (ret) {
	355	cmd_args.thinpool = orig;
	356	}
	357
	358	cmd_args.lv = lv;
	359	cmd_args.source_lv = orig;
	360	cmd_args.size = sz;
	361	TRACE("Creating new lvm snapshot \"%s\" of \"%s\" with size \"%s\"", lv,
	362	orig, sz);
	363	ret = run_command(cmd_output, sizeof(cmd_output),
	364	lvm_snapshot_exec_wrapper, (void *)&cmd_args);
	365	if (ret < 0) {
	366	ERROR("Failed to create logical volume \"%s\": %s", orig,
	367	cmd_output);
	368	free(pathdup);
	369	return -1;
	370	}
	371
	372	free(pathdup);
	373	return 0;
	374	}
	375
	376	int lvm_clonepaths(struct lxc_storage orig, struct lxc_storage new,
	377	const char oldname, const char cname, const char *oldpath,
	378	const char *lxcpath, int snap, uint64_t newsize,
	379	struct lxc_conf *conf)
	380	{
	381	int len, ret;
	382	const char *vg;
	383
	384	if (!orig->src \|\| !orig->dest)
	385	return -1;
	386
	387	if (strcmp(orig->type, "lvm") && snap) {
	388	ERROR("LVM snapshot from \"%s\" storage driver is not supported",
	389	orig->type);
	390	return -1;
	391	}
	392
	393	if (strcmp(orig->type, "lvm")) {
	394	vg = lxc_global_config_value("lxc.bdev.lvm.vg");
	395	new->src = lxc_string_join(
	396	"/",
	397	(const char *[]){"lvm:", "dev", vg, cname, NULL},
	398	false);
	399	} else {
	400	char dup, slider, *src;
	401
	402	src = lxc_storage_get_path(orig->src, orig->type);
	403
	404	dup = strdup(src);
	405	if (!dup) {
	406	ERROR("Failed to duplicate string \"%s\"", src);
	407	return -1;
	408	}
	409
	410	slider = strrchr(dup, '/');
	411	if (!slider) {
	412	ERROR("Failed to detect \"/\" in string \"%s\"", dup);
	413	free(dup);
	414	return -1;
	415	}
	416	*slider = '\0';
	417	slider = dup;
	418
	419	new->src = lxc_string_join(
	420	"/",
	421	(const char []){"lvm:", slider == '/' ? ++slider : slider,
	422	cname, NULL},
	423	false);
	424	free(dup);
	425	}
	426	if (!new->src) {
	427	ERROR("Failed to create string");
	428	return -1;
	429	}
	430
	431	if (orig->mntopts) {
	432	new->mntopts = strdup(orig->mntopts);
	433	if (!new->mntopts) {
	434	ERROR("Failed to duplicate string \"%s\"", orig->mntopts);
	435	return -1;
	436	}
	437	}
	438
	439	len = strlen(lxcpath) + strlen(cname) + strlen("rootfs") + 3;
	440	new->dest = malloc(len);
	441	if (!new->dest) {
	442	ERROR("Failed to allocate memory");
	443	return -1;
	444	}
	445
	446	ret = snprintf(new->dest, len, "%s/%s/rootfs", lxcpath, cname);
	447	if (ret < 0 \|\| ret >= len) {
	448	ERROR("Failed to create string");
	449	return -1;
	450	}
	451
	452	ret = mkdir_p(new->dest, 0755);
	453	if (ret < 0) {
	454	SYSERROR("Failed to create directory \"%s\"", new->dest);
	455	return -1;
	456	}
	457
	458	return 0;
	459	}
	460
	461	bool lvm_create_clone(struct lxc_conf conf, struct lxc_storage orig,
	462	struct lxc_storage *new, uint64_t newsize)
	463	{
	464	char *src;
	465	const char *thinpool;
	466	int ret;
	467	struct rsync_data data;
	468	char *cmd_args[2];
	469	char cmd_output[MAXPATHLEN] = {0};
	470	char fstype[100] = "ext4";
	471	uint64_t size = newsize;
	472
	473	if (is_blktype(orig)) {
	474	/* detect size */
	475	if (!newsize && blk_getsize(orig, &size) < 0) {
	476	ERROR("Failed to detect size of logical volume \"%s\"",
	477	orig->src);
	478	return -1;
	479	}
	480
	481	/* detect filesystem */
	482	if (detect_fs(orig, fstype, 100) < 0) {
	483	INFO("Failed to detect filesystem type for \"%s\"", orig->src);
	484	return -1;
	485	}
	486	} else if (!newsize) {
	487	size = DEFAULT_FS_SIZE;
	488	}
	489
	490	src = lxc_storage_get_path(new->src, "lvm");
	491	thinpool = lxc_global_config_value("lxc.bdev.lvm.thin_pool");
	492
	493	ret = do_lvm_create(src, size, thinpool);
	494	if (ret < 0) {
	495	ERROR("Failed to create lvm storage volume \"%s\"", src);
	496	return -1;
	497	}
	498
	499	cmd_args[0] = fstype;
	500	cmd_args[1] = src;
	501	ret = run_command(cmd_output, sizeof(cmd_output),
	502	do_mkfs_exec_wrapper, (void *)cmd_args);
	503	if (ret < 0) {
	504	ERROR("Failed to create new filesystem \"%s\" for lvm storage "
	505	"volume \"%s\": %s", fstype, src, cmd_output);
	506	return -1;
	507	}
	508
	509	data.orig = orig;
	510	data.new = new;
	511	ret = run_command(cmd_output, sizeof(cmd_output),
	512	lxc_storage_rsync_exec_wrapper, (void *)&data);
	513	if (ret < 0) {
	514	ERROR("Failed to rsync from \"%s\" to \"%s\"", orig->dest,
	515	new->dest);
	516	return false;
	517	}
	518
	519	TRACE("Created lvm storage volume \"%s\"", new->dest);
	520	return true;
	521	}
	522
	523	bool lvm_create_snapshot(struct lxc_conf conf, struct lxc_storage orig,
	524	struct lxc_storage *new, uint64_t newsize)
	525	{
	526	int ret;
	527	char newsrc, origsrc;
	528	uint64_t size = newsize;
	529
	530	if (is_blktype(orig)) {
	531	if (!newsize && blk_getsize(orig, &size) < 0) {
	532	ERROR("Failed to detect size of logical volume \"%s\"",
	533	orig->src);
	534	return -1;
	535	}
	536	} else if (!newsize) {
	537	size = DEFAULT_FS_SIZE;
	538	}
	539
	540	origsrc = lxc_storage_get_path(orig->src, "lvm");
	541	newsrc = lxc_storage_get_path(new->src, "lvm");
	542
	543	ret = lvm_snapshot(origsrc, newsrc, size);
	544	if (ret < 0) {
	545	ERROR("Failed to create lvm \"%s\" snapshot of \"%s\"",
	546	new->src, orig->src);
	547	return false;
	548	}
	549
	550	TRACE("Created lvm snapshot \"%s\" from \"%s\"", new->dest, orig->dest);
	551	return true;
	552	}
	553
	554	int lvm_destroy(struct lxc_storage *orig)
	555	{
	556	int ret;
	557	char cmd_output[MAXPATHLEN];
	558	struct lvcreate_args cmd_args = {0};
	559
	560	cmd_args.lv = lxc_storage_get_path(orig->src, "lvm");
	561	ret = run_command(cmd_output, sizeof(cmd_output),
	562	lvm_destroy_exec_wrapper, (void *)&cmd_args);
	563	if (ret < 0) {
	564	ERROR("Failed to destroy logical volume \"%s\": %s", orig->src,
	565	cmd_output);
	566	return -1;
	567	}
	568
	569	TRACE("Destroyed logical volume \"%s\"", orig->src);
	570	return 0;
	571	}
	572
	573	int lvm_create(struct lxc_storage bdev, const char dest, const char *n,
	574	struct bdev_specs *specs)
	575	{
	576	const char vg, thinpool, fstype, lv = n;
	577	uint64_t sz;
	578	int ret, len;
	579	const char *cmd_args[2];
	580	char cmd_output[MAXPATHLEN];
	581
	582	if (!specs)
	583	return -1;
	584
	585	vg = specs->lvm.vg;
	586	if (!vg)
	587	vg = lxc_global_config_value("lxc.bdev.lvm.vg");
	588
	589	thinpool = specs->lvm.thinpool;
	590	if (!thinpool)
	591	thinpool = lxc_global_config_value("lxc.bdev.lvm.thin_pool");
	592
	593	/* /dev/$vg/$lv */
	594	if (specs->lvm.lv)
	595	lv = specs->lvm.lv;
	596
	597	len = strlen(vg) + strlen(lv) + 4 + 7;
	598	bdev->src = malloc(len);
	599	if (!bdev->src) {
	600	ERROR("Failed to allocate memory");
	601	return -1;
	602	}
	603
	604	ret = snprintf(bdev->src, len, "lvm:/dev/%s/%s", vg, lv);
	605	if (ret < 0 \|\| ret >= len) {
	606	ERROR("Failed to create string");
	607	return -1;
	608	}
	609
	610	/* size is in bytes */
	611	sz = specs->fssize;
	612	if (!sz)
	613	sz = DEFAULT_FS_SIZE;
	614
	615	ret = do_lvm_create(bdev->src + 4, sz, thinpool);
	616	if (ret < 0) {
	617	ERROR("Error creating new logical volume \"%s\" of size "
	618	"\"%" PRIu64 " bytes\"", bdev->src, sz);
	619	return -1;
	620	}
	621
	622	fstype = specs->fstype;
	623	if (!fstype)
	624	fstype = DEFAULT_FSTYPE;
	625
	626	cmd_args[0] = fstype;
	627	cmd_args[1] = lxc_storage_get_path(bdev->src, bdev->type);
	628	ret = run_command(cmd_output, sizeof(cmd_output), do_mkfs_exec_wrapper,
	629	(void *)cmd_args);
	630	if (ret < 0) {
	631	ERROR("Failed to create new logical volume \"%s\": %s",
	632	bdev->src, cmd_output);
	633	return -1;
	634	}
	635
	636	bdev->dest = strdup(dest);
	637	if (!bdev->dest) {
	638	ERROR("Failed to duplicate string \"%s\"", dest);
	639	return -1;
	640	}
	641
	642	ret = mkdir_p(bdev->dest, 0755);
	643	if (ret < 0) {
	644	SYSERROR("Failed to create directory \"%s\"", bdev->dest);
	645	return -1;
	646	}
	647
	648	TRACE("Created new logical volume \"%s\"", bdev->dest);
	649	return 0;
	650	}