[thirdparty/util-linux.git] / libmount / src / context_loopdev.c

/*
 * Copyright (C) 2011 Karel Zak <kzak@redhat.com>
 *
 * This file may be redistributed under the terms of the
 * GNU Lesser General Public License.
 */

/*
 * DOCS: - "lo@" prefix for fstype is unsupported
 */

#include <blkid.h>

#include "mountP.h"
#include "loopdev.h"
#include "linux_version.h"


int mnt_context_is_loopdev(struct libmnt_context *cxt)
{
	const char *type, *src;

	assert(cxt);

	/* The mount flags have to be merged, otherwise we have to use
	 * expensive mnt_context_get_user_mflags() instead of cxt->user_mountflags. */
	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));

	if (!cxt->fs)
		return 0;
	src = mnt_fs_get_srcpath(cxt->fs);
	if (!src)
		return 0;		/* backing file not set */

	if (cxt->user_mountflags & (MNT_MS_LOOP |
				    MNT_MS_OFFSET |
				    MNT_MS_SIZELIMIT)) {

		DBG(CXT, mnt_debug_h(cxt, "loopdev specific options detected"));
		return 1;
	}

	if (cxt->mountflags & (MS_BIND | MS_MOVE | MS_PROPAGATION))
		return 0;

	/* Automatically create a loop device from a regular file if a
	 * filesystem is not specified or the filesystem is known for libblkid
	 * (these filesystems work with block devices only). The file size
	 * should be at least 1KiB otherwise we will create empty loopdev where
	 * is no mountable filesystem...
	 *
	 * Note that there is not a restriction (on kernel side) that prevents regular
	 * file as a mount(2) source argument. A filesystem that is able to mount
	 * regular files could be implemented.
	 */
	type = mnt_fs_get_fstype(cxt->fs);

	if (mnt_fs_is_regular(cxt->fs) &&
	    (!type || strcmp(type, "auto") == 0 || blkid_known_fstype(type))) {
		struct stat st;

		if (stat(src, &st) == 0 && S_ISREG(st.st_mode) &&
		    st.st_size > 1024)
			return 1;
	}

	return 0;
}


/* Check, if there already exists a mounted loop device on the mountpoint node
 * with the same parameters.
 */
static int is_mounted_same_loopfile(struct libmnt_context *cxt,
				    const char *target,
				    const char *backing_file,
				    uint64_t offset)
{
	struct libmnt_table *tb;
	struct libmnt_iter itr;
	struct libmnt_fs *fs;
	struct libmnt_cache *cache;

	assert(cxt);
	assert(cxt->fs);
	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));

	if (!target || !backing_file || mnt_context_get_mtab(cxt, &tb))
		return 0;

	DBG(CXT, mnt_debug_h(cxt, "checking if %s mounted on %s",
				backing_file, target));

	cache = mnt_context_get_cache(cxt);
	mnt_reset_iter(&itr, MNT_ITER_BACKWARD);

	/* Search for mountpoint node in mtab, procceed if any of these has the
	 * loop option set or the device is a loop device
	 */
	while (mnt_table_next_fs(tb, &itr, &fs) == 0) {
		const char *src = mnt_fs_get_source(fs);
		const char *opts = mnt_fs_get_user_options(fs);
		char *val;
		size_t len;
		int res = 0;

		if (!src || !mnt_fs_match_target(fs, target, cache))
			continue;

		if (strncmp(src, "/dev/loop", 9) == 0) {
			res = loopdev_is_used((char *) src, backing_file,
					offset, LOOPDEV_FL_OFFSET);

		} else if (opts && (cxt->user_mountflags & MNT_MS_LOOP) &&
		    mnt_optstr_get_option(opts, "loop", &val, &len) == 0 && val) {

			val = strndup(val, len);
			res = loopdev_is_used((char *) val, backing_file,
					offset, LOOPDEV_FL_OFFSET);
			free(val);
		}

		if (res) {
			DBG(CXT, mnt_debug_h(cxt, "%s already mounted", backing_file));
			return 1;
		}
	}

	return 0;
}

int mnt_context_setup_loopdev(struct libmnt_context *cxt)
{
	const char *backing_file, *optstr, *loopdev = NULL;
	char *val = NULL;
	size_t len;
	struct loopdev_cxt lc;
	int rc = 0, lo_flags = 0;
	uint64_t offset = 0, sizelimit = 0;

	assert(cxt);
	assert(cxt->fs);
	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));

	backing_file = mnt_fs_get_srcpath(cxt->fs);
	if (!backing_file)
		return -EINVAL;

	DBG(CXT, mnt_debug_h(cxt, "trying to setup loopdev for %s", backing_file));

	if (cxt->mountflags & MS_RDONLY) {
		DBG(CXT, mnt_debug_h(cxt, "enabling READ-ONLY flag"));
		lo_flags |= LO_FLAGS_READ_ONLY;
	}

	rc = loopcxt_init(&lc, 0);
	if (rc)
		return rc;

	ON_DBG(CXT, loopcxt_enable_debug(&lc, 1));

	optstr = mnt_fs_get_user_options(cxt->fs);

	/*
	 * loop=
	 */
	if (rc == 0 && (cxt->user_mountflags & MNT_MS_LOOP) &&
	    mnt_optstr_get_option(optstr, "loop", &val, &len) == 0 && val) {

		val = strndup(val, len);
		rc = val ? loopcxt_set_device(&lc, val) : -ENOMEM;
		free(val);

		if (rc == 0)
			loopdev = loopcxt_get_device(&lc);
	}

	/*
	 * offset=
	 */
	if (rc == 0 && (cxt->user_mountflags & MNT_MS_OFFSET) &&
	    mnt_optstr_get_option(optstr, "offset", &val, &len) == 0) {
		rc = mnt_parse_offset(val, len, &offset);
		if (rc) {
			DBG(CXT, mnt_debug_h(cxt, "failed to parse offset="));
			rc = -MNT_ERR_MOUNTOPT;
		}
	}

	/*
	 * sizelimit=
	 */
	if (rc == 0 && (cxt->user_mountflags & MNT_MS_SIZELIMIT) &&
	    mnt_optstr_get_option(optstr, "sizelimit", &val, &len) == 0) {
		rc = mnt_parse_offset(val, len, &sizelimit);
		if (rc) {
			DBG(CXT, mnt_debug_h(cxt, "failed to parse sizelimit="));
			rc = -MNT_ERR_MOUNTOPT;
		}
	}

	/*
	 * encryption=
	 */
	if (rc == 0 && (cxt->user_mountflags & MNT_MS_ENCRYPTION) &&
	    mnt_optstr_get_option(optstr, "encryption", &val, &len) == 0) {
		DBG(CXT, mnt_debug_h(cxt, "encryption no longer supported"));
		rc = -MNT_ERR_MOUNTOPT;
	}

	if (rc == 0 && is_mounted_same_loopfile(cxt,
				mnt_context_get_target(cxt),
				backing_file, offset))
		rc = -EBUSY;

	if (rc)
		goto done;

	/* since 2.6.37 we don't have to store backing filename to mtab
	 * because kernel provides the name in /sys.
	 */
	if (get_linux_version() >= KERNEL_VERSION(2, 6, 37) ||
	    !cxt->mtab_writable) {
		DBG(CXT, mnt_debug_h(cxt, "enabling AUTOCLEAR flag"));
		lo_flags |= LO_FLAGS_AUTOCLEAR;
	}

	do {
		/* found free device */
		if (!loopdev) {
			rc = loopcxt_find_unused(&lc);
			if (rc)
				goto done;
			DBG(CXT, mnt_debug_h(cxt, "trying to use %s",
						loopcxt_get_device(&lc)));
		}

		/* set device attributes
		 * -- note that loopcxt_find_unused() resets "lc"
		 */
		rc = loopcxt_set_backing_file(&lc, backing_file);

		if (!rc && offset)
			rc = loopcxt_set_offset(&lc, offset);
		if (!rc && sizelimit)
			rc = loopcxt_set_sizelimit(&lc, sizelimit);
		if (!rc)
			loopcxt_set_flags(&lc, lo_flags);
		if (rc) {
			DBG(CXT, mnt_debug_h(cxt, "failed to set loopdev attributes"));
			goto done;
		}

		/* setup the device */
		rc = loopcxt_setup_device(&lc);
		if (!rc)
			break;		/* success */

		if (loopdev || rc != -EBUSY) {
			DBG(CXT, mnt_debug_h(cxt, "failed to setup device"));
			rc = -MNT_ERR_LOOPDEV;
			goto done;
		}
		DBG(CXT, mnt_debug_h(cxt, "loopdev stolen...trying again"));
	} while (1);

	if (!rc)
		rc = mnt_fs_set_source(cxt->fs, loopcxt_get_device(&lc));

	if (!rc) {
		/* success */
		cxt->flags |= MNT_FL_LOOPDEV_READY;

		if ((cxt->user_mountflags & MNT_MS_LOOP) &&
		    loopcxt_is_autoclear(&lc)) {
			/*
			 * autoclear flag accepted by kernel, don't store
			 * the "loop=" option to mtab.
			 */
			cxt->user_mountflags &= ~MNT_MS_LOOP;
			mnt_optstr_remove_option(&cxt->fs->user_optstr, "loop");
		}

		if (!(cxt->mountflags & MS_RDONLY) &&
		    loopcxt_is_readonly(&lc))
			/*
			 * mount planned read-write, but loopdev is read-only,
			 * let's fix mount options...
			 */
			mnt_context_set_mflags(cxt, cxt->mountflags | MS_RDONLY);

		/* we have to keep the device open until mount(1),
		 * otherwise it will auto-cleared by kernel
		 */
		cxt->loopdev_fd = loopcxt_get_fd(&lc);
		loopcxt_set_fd(&lc, -1, 0);
	}
done:
	loopcxt_deinit(&lc);
	return rc;
}

/*
 * Deletes loop device
 */
int mnt_context_delete_loopdev(struct libmnt_context *cxt)
{
	const char *src;
	int rc;

	assert(cxt);
	assert(cxt->fs);

	src = mnt_fs_get_srcpath(cxt->fs);
	if (!src)
		return -EINVAL;

	if (cxt->loopdev_fd > -1)
		close(cxt->loopdev_fd);

	rc = loopdev_delete(src);
	cxt->flags &= ~MNT_FL_LOOPDEV_READY;
	cxt->loopdev_fd = -1;

	DBG(CXT, mnt_debug_h(cxt, "loopdev deleted [rc=%d]", rc));
	return rc;
}

/*
 * Clears loopdev stuff in context, should be called after
 * failed or successful mount(2).
 */
int mnt_context_clear_loopdev(struct libmnt_context *cxt)
{
	assert(cxt);

	if (mnt_context_get_status(cxt) == 0 &&
	    (cxt->flags & MNT_FL_LOOPDEV_READY)) {
		/*
		 * mount(2) failed, delete loopdev
		 */
		mnt_context_delete_loopdev(cxt);

	} else if (cxt->loopdev_fd > -1) {
		/*
		 * mount(2) success, close the device
		 */
		DBG(CXT, mnt_debug_h(cxt, "closing loopdev FD"));
		close(cxt->loopdev_fd);
	}
	cxt->loopdev_fd = -1;
	return 0;
}
Commit	Line	Data
7f8b2bf3 KZ	1	/*
	2	* Copyright (C) 2011 Karel Zak <kzak@redhat.com>
	3	*
	4	* This file may be redistributed under the terms of the
	5	* GNU Lesser General Public License.
	6	*/
	7
	8	/*
	9	* DOCS: - "lo@" prefix for fstype is unsupported
7f8b2bf3 KZ	10	*/
	11
	12	#include <blkid.h>
	13
	14	#include "mountP.h"
	15	#include "loopdev.h"
	16	#include "linux_version.h"
	17
	18
	19	int mnt_context_is_loopdev(struct libmnt_context *cxt)
	20	{
	21	const char type, src;
7f8b2bf3 KZ	22
7f8b2bf3 KZ	23	assert(cxt);
c8512236	24
7f8b2bf3 KZ	25	/* The mount flags have to be merged, otherwise we have to use
	26	* expensive mnt_context_get_user_mflags() instead of cxt->user_mountflags. */
	27	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
	28
	29	if (!cxt->fs)
	30	return 0;
	31	src = mnt_fs_get_srcpath(cxt->fs);
	32	if (!src)
	33	return 0; /* backing file not set */
	34
	35	if (cxt->user_mountflags & (MNT_MS_LOOP \|
	36	MNT_MS_OFFSET \|
5cf05c71	37	MNT_MS_SIZELIMIT)) {
c8512236 KZ	38
c8512236 KZ	39	DBG(CXT, mnt_debug_h(cxt, "loopdev specific options detected"));
7f8b2bf3	40	return 1;
c8512236	41	}
7f8b2bf3 KZ	42
	43	if (cxt->mountflags & (MS_BIND \| MS_MOVE \| MS_PROPAGATION))
	44	return 0;
	45
c8512236 KZ	46	/* Automatically create a loop device from a regular file if a
	47	* filesystem is not specified or the filesystem is known for libblkid
	48	* (these filesystems work with block devices only). The file size
	49	* should be at least 1KiB otherwise we will create empty loopdev where
	50	* is no mountable filesystem...
7f8b2bf3 KZ	51	*
	52	* Note that there is not a restriction (on kernel side) that prevents regular
	53	* file as a mount(2) source argument. A filesystem that is able to mount
	54	* regular files could be implemented.
	55	*/
	56	type = mnt_fs_get_fstype(cxt->fs);
7f8b2bf3	57
c70d9d76	58	if (mnt_fs_is_regular(cxt->fs) &&
7f8b2bf3 KZ	59	(!type \|\| strcmp(type, "auto") == 0 \|\| blkid_known_fstype(type))) {
	60	struct stat st;
	61
c8512236 KZ	62	if (stat(src, &st) == 0 && S_ISREG(st.st_mode) &&
	63	st.st_size > 1024)
	64	return 1;
7f8b2bf3 KZ	65	}
7f8b2bf3 KZ	66
c8512236	67	return 0;
7f8b2bf3 KZ	68	}
7f8b2bf3 KZ	69
8b470b20 KZ	70
	71	/* Check, if there already exists a mounted loop device on the mountpoint node
	72	* with the same parameters.
	73	*/
	74	static int is_mounted_same_loopfile(struct libmnt_context *cxt,
	75	const char *target,
	76	const char *backing_file,
	77	uint64_t offset)
	78	{
	79	struct libmnt_table *tb;
	80	struct libmnt_iter itr;
	81	struct libmnt_fs *fs;
	82	struct libmnt_cache *cache;
	83
	84	assert(cxt);
	85	assert(cxt->fs);
	86	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
	87
	88	if (!target \|\| !backing_file \|\| mnt_context_get_mtab(cxt, &tb))
	89	return 0;
	90
b2ddfb59	91	DBG(CXT, mnt_debug_h(cxt, "checking if %s mounted on %s",
8b470b20 KZ	92	backing_file, target));
	93
	94	cache = mnt_context_get_cache(cxt);
	95	mnt_reset_iter(&itr, MNT_ITER_BACKWARD);
	96
	97	/* Search for mountpoint node in mtab, procceed if any of these has the
	98	* loop option set or the device is a loop device
	99	*/
	100	while (mnt_table_next_fs(tb, &itr, &fs) == 0) {
	101	const char *src = mnt_fs_get_source(fs);
	102	const char *opts = mnt_fs_get_user_options(fs);
	103	char *val;
	104	size_t len;
	105	int res = 0;
	106
	107	if (!src \|\| !mnt_fs_match_target(fs, target, cache))
	108	continue;
	109
	110	if (strncmp(src, "/dev/loop", 9) == 0) {
	111	res = loopdev_is_used((char *) src, backing_file,
	112	offset, LOOPDEV_FL_OFFSET);
	113
	114	} else if (opts && (cxt->user_mountflags & MNT_MS_LOOP) &&
	115	mnt_optstr_get_option(opts, "loop", &val, &len) == 0 && val) {
	116
	117	val = strndup(val, len);
	118	res = loopdev_is_used((char *) val, backing_file,
	119	offset, LOOPDEV_FL_OFFSET);
	120	free(val);
	121	}
	122
	123	if (res) {
	124	DBG(CXT, mnt_debug_h(cxt, "%s already mounted", backing_file));
	125	return 1;
	126	}
	127	}
	128
	129	return 0;
	130	}
	131
7f8b2bf3 KZ	132	int mnt_context_setup_loopdev(struct libmnt_context *cxt)
7f8b2bf3 KZ	133	{
f0d3ff0a	134	const char backing_file, optstr, *loopdev = NULL;
5cf05c71	135	char *val = NULL;
7f8b2bf3 KZ	136	size_t len;
7f8b2bf3 KZ	137	struct loopdev_cxt lc;
b9fd3340 KZ	138	int rc = 0, lo_flags = 0;
b9fd3340 KZ	139	uint64_t offset = 0, sizelimit = 0;
7f8b2bf3 KZ	140
	141	assert(cxt);
	142	assert(cxt->fs);
	143	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
	144
	145	backing_file = mnt_fs_get_srcpath(cxt->fs);
	146	if (!backing_file)
	147	return -EINVAL;
	148
	149	DBG(CXT, mnt_debug_h(cxt, "trying to setup loopdev for %s", backing_file));
	150
	151	if (cxt->mountflags & MS_RDONLY) {
	152	DBG(CXT, mnt_debug_h(cxt, "enabling READ-ONLY flag"));
	153	lo_flags \|= LO_FLAGS_READ_ONLY;
	154	}
365e5a7c	155
defa0710 KZ	156	rc = loopcxt_init(&lc, 0);
	157	if (rc)
	158	return rc;
7f8b2bf3	159
365e5a7c KZ	160	ON_DBG(CXT, loopcxt_enable_debug(&lc, 1));
365e5a7c KZ	161
b9fd3340	162	optstr = mnt_fs_get_user_options(cxt->fs);
7f8b2bf3	163
b9fd3340 KZ	164	/*
	165	* loop=
	166	*/
	167	if (rc == 0 && (cxt->user_mountflags & MNT_MS_LOOP) &&
	168	mnt_optstr_get_option(optstr, "loop", &val, &len) == 0 && val) {
	169
	170	val = strndup(val, len);
	171	rc = val ? loopcxt_set_device(&lc, val) : -ENOMEM;
	172	free(val);
f0d3ff0a KZ	173
	174	if (rc == 0)
	175	loopdev = loopcxt_get_device(&lc);
b9fd3340 KZ	176	}
	177
	178	/*
	179	* offset=
	180	*/
	181	if (rc == 0 && (cxt->user_mountflags & MNT_MS_OFFSET) &&
	182	mnt_optstr_get_option(optstr, "offset", &val, &len) == 0) {
	183	rc = mnt_parse_offset(val, len, &offset);
61f5ff6c	184	if (rc) {
b9fd3340	185	DBG(CXT, mnt_debug_h(cxt, "failed to parse offset="));
61f5ff6c KZ	186	rc = -MNT_ERR_MOUNTOPT;
61f5ff6c KZ	187	}
7f8b2bf3 KZ	188	}
7f8b2bf3 KZ	189
b9fd3340 KZ	190	/*
	191	* sizelimit=
	192	*/
	193	if (rc == 0 && (cxt->user_mountflags & MNT_MS_SIZELIMIT) &&
	194	mnt_optstr_get_option(optstr, "sizelimit", &val, &len) == 0) {
	195	rc = mnt_parse_offset(val, len, &sizelimit);
61f5ff6c	196	if (rc) {
b9fd3340	197	DBG(CXT, mnt_debug_h(cxt, "failed to parse sizelimit="));
61f5ff6c KZ	198	rc = -MNT_ERR_MOUNTOPT;
61f5ff6c KZ	199	}
b9fd3340 KZ	200	}
b9fd3340 KZ	201
1a7a421e KZ	202	/*
	203	* encryption=
	204	*/
	205	if (rc == 0 && (cxt->user_mountflags & MNT_MS_ENCRYPTION) &&
	206	mnt_optstr_get_option(optstr, "encryption", &val, &len) == 0) {
5cf05c71 LN	207	DBG(CXT, mnt_debug_h(cxt, "encryption no longer supported"));
5cf05c71 LN	208	rc = -MNT_ERR_MOUNTOPT;
1a7a421e KZ	209	}
1a7a421e KZ	210
8b470b20 KZ	211	if (rc == 0 && is_mounted_same_loopfile(cxt,
	212	mnt_context_get_target(cxt),
	213	backing_file, offset))
	214	rc = -EBUSY;
	215
b9fd3340 KZ	216	if (rc)
	217	goto done;
	218
7f8b2bf3 KZ	219	/* since 2.6.37 we don't have to store backing filename to mtab
	220	* because kernel provides the name in /sys.
	221	*/
	222	if (get_linux_version() >= KERNEL_VERSION(2, 6, 37) \|\|
	223	!cxt->mtab_writable) {
	224	DBG(CXT, mnt_debug_h(cxt, "enabling AUTOCLEAR flag"));
	225	lo_flags \|= LO_FLAGS_AUTOCLEAR;
	226	}
	227
	228	do {
	229	/* found free device */
	230	if (!loopdev) {
	231	rc = loopcxt_find_unused(&lc);
	232	if (rc)
	233	goto done;
	234	DBG(CXT, mnt_debug_h(cxt, "trying to use %s",
	235	loopcxt_get_device(&lc)));
	236	}
	237
b9fd3340 KZ	238	/* set device attributes
	239	* -- note that loopcxt_find_unused() resets "lc"
	240	*/
7f8b2bf3	241	rc = loopcxt_set_backing_file(&lc, backing_file);
7f8b2bf3	242
b9fd3340 KZ	243	if (!rc && offset)
	244	rc = loopcxt_set_offset(&lc, offset);
	245	if (!rc && sizelimit)
	246	rc = loopcxt_set_sizelimit(&lc, sizelimit);
	247	if (!rc)
	248	loopcxt_set_flags(&lc, lo_flags);
	249	if (rc) {
	250	DBG(CXT, mnt_debug_h(cxt, "failed to set loopdev attributes"));
	251	goto done;
	252	}
7f8b2bf3 KZ	253
	254	/* setup the device */
	255	rc = loopcxt_setup_device(&lc);
	256	if (!rc)
	257	break; /* success */
	258
	259	if (loopdev \|\| rc != -EBUSY) {
	260	DBG(CXT, mnt_debug_h(cxt, "failed to setup device"));
82756a74	261	rc = -MNT_ERR_LOOPDEV;
b9fd3340	262	goto done;
7f8b2bf3 KZ	263	}
	264	DBG(CXT, mnt_debug_h(cxt, "loopdev stolen...trying again"));
	265	} while (1);
	266
	267	if (!rc)
	268	rc = mnt_fs_set_source(cxt->fs, loopcxt_get_device(&lc));
	269
	270	if (!rc) {
	271	/* success */
	272	cxt->flags \|= MNT_FL_LOOPDEV_READY;
	273
	274	if ((cxt->user_mountflags & MNT_MS_LOOP) &&
f0d3ff0a	275	loopcxt_is_autoclear(&lc)) {
7f8b2bf3 KZ	276	/*
	277	* autoclear flag accepted by kernel, don't store
	278	* the "loop=" option to mtab.
	279	*/
	280	cxt->user_mountflags &= ~MNT_MS_LOOP;
f0d3ff0a KZ	281	mnt_optstr_remove_option(&cxt->fs->user_optstr, "loop");
f0d3ff0a KZ	282	}
7f8b2bf3 KZ	283
	284	if (!(cxt->mountflags & MS_RDONLY) &&
	285	loopcxt_is_readonly(&lc))
	286	/*
	287	* mount planned read-write, but loopdev is read-only,
	288	* let's fix mount options...
	289	*/
f9906424	290	mnt_context_set_mflags(cxt, cxt->mountflags \| MS_RDONLY);
7f8b2bf3 KZ	291
	292	/* we have to keep the device open until mount(1),
	293	* otherwise it will auto-cleared by kernel
	294	*/
	295	cxt->loopdev_fd = loopcxt_get_fd(&lc);
	296	loopcxt_set_fd(&lc, -1, 0);
	297	}
	298	done:
	299	loopcxt_deinit(&lc);
	300	return rc;
	301	}
	302
	303	/*
	304	* Deletes loop device
	305	*/
	306	int mnt_context_delete_loopdev(struct libmnt_context *cxt)
	307	{
	308	const char *src;
	309	int rc;
	310
	311	assert(cxt);
	312	assert(cxt->fs);
	313
	314	src = mnt_fs_get_srcpath(cxt->fs);
	315	if (!src)
	316	return -EINVAL;
	317
	318	if (cxt->loopdev_fd > -1)
	319	close(cxt->loopdev_fd);
	320
	321	rc = loopdev_delete(src);
	322	cxt->flags &= ~MNT_FL_LOOPDEV_READY;
	323	cxt->loopdev_fd = -1;
	324
	325	DBG(CXT, mnt_debug_h(cxt, "loopdev deleted [rc=%d]", rc));
	326	return rc;
	327	}
	328
	329	/*
	330	* Clears loopdev stuff in context, should be called after
	331	* failed or successful mount(2).
	332	*/
	333	int mnt_context_clear_loopdev(struct libmnt_context *cxt)
	334	{
	335	assert(cxt);
	336
	337	if (mnt_context_get_status(cxt) == 0 &&
	338	(cxt->flags & MNT_FL_LOOPDEV_READY)) {
	339	/*
	340	* mount(2) failed, delete loopdev
	341	*/
	342	mnt_context_delete_loopdev(cxt);
	343
	344	} else if (cxt->loopdev_fd > -1) {
	345	/*
	346	* mount(2) success, close the device
	347	*/
	348	DBG(CXT, mnt_debug_h(cxt, "closing loopdev FD"));
	349	close(cxt->loopdev_fd);
	350	}
	351	cxt->loopdev_fd = -1;
	352	return 0;
	353	}
	354