* Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.

/* $NetBSD: libdm-iface.c,v 1.3 2010/12/26 14:48:34 christos Exp $ */

/*
* Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
*
* This file is part of the device-mapper userspace tools.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser 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 "dmlib.h"
#include "libdm-targets.h"
#include "libdm-common.h"

#ifdef DM_COMPAT
# include "libdm-compat.h"
#endif

#include <fcntl.h>
#include <dirent.h>
#include <sys/ioctl.h>
#include <sys/utsname.h>
#include <limits.h>

#ifdef linux
# include "kdev_t.h"
# include <linux/limits.h>
#else
# define MAJOR(x) major((x))
# define MINOR(x) minor((x))
# define MKDEV(x,y) makedev((x),(y))
#endif

#include "dm-ioctl.h"

/*
* Ensure build compatibility.
* The hard-coded versions here are the highest present
* in the _cmd_data arrays.
*/

#if !((DM_VERSION_MAJOR == 1 && DM_VERSION_MINOR >= 0) || \
(DM_VERSION_MAJOR == 4 && DM_VERSION_MINOR >= 0))
#error The version of dm-ioctl.h included is incompatible.
#endif

/* FIXME This should be exported in device-mapper.h */
#define DM_NAME "device-mapper"

#define PROC_MISC "/proc/misc"
#define PROC_DEVICES "/proc/devices"
#define MISC_NAME "misc"

#define NUMBER_OF_MAJORS 4096

/* dm major version no for running kernel */
static unsigned _dm_version = DM_VERSION_MAJOR;
static unsigned _dm_version_minor = 0;
static unsigned _dm_version_patchlevel = 0;
static int _log_suppress = 0;

/*
* If the kernel dm driver only supports one major number
* we store it in _dm_device_major. Otherwise we indicate
* which major numbers have been claimed by device-mapper
* in _dm_bitset.
*/
static unsigned _dm_multiple_major_support = 1;
static dm_bitset_t _dm_bitset = NULL;
static uint32_t _dm_device_major = 0;

static int _control_fd = -1;
static int _version_checked = 0;
static int _version_ok = 1;
static unsigned _ioctl_buffer_double_factor = 0;

/*
* Support both old and new major numbers to ease the transition.
* Clumsy, but only temporary.
*/
#if DM_VERSION_MAJOR == 4 && defined(DM_COMPAT)
const int _dm_compat = 1;
#else
const int _dm_compat = 0;
#endif

/* *INDENT-OFF* */
static struct cmd_data _cmd_data_v4[] = {
{"create", DM_DEV_CREATE, {4, 0, 0}},
{"reload", DM_TABLE_LOAD, {4, 0, 0}},
{"remove", DM_DEV_REMOVE, {4, 0, 0}},
{"remove_all", DM_REMOVE_ALL, {4, 0, 0}},
{"suspend", DM_DEV_SUSPEND, {4, 0, 0}},
{"resume", DM_DEV_SUSPEND, {4, 0, 0}},
{"info", DM_DEV_STATUS, {4, 0, 0}},
{"deps", DM_TABLE_DEPS, {4, 0, 0}},
{"rename", DM_DEV_RENAME, {4, 0, 0}},
{"version", DM_VERSION, {4, 0, 0}},
{"status", DM_TABLE_STATUS, {4, 0, 0}},
{"table", DM_TABLE_STATUS, {4, 0, 0}},
{"waitevent", DM_DEV_WAIT, {4, 0, 0}},
{"names", DM_LIST_DEVICES, {4, 0, 0}},
{"clear", DM_TABLE_CLEAR, {4, 0, 0}},
{"mknodes", DM_DEV_STATUS, {4, 0, 0}},
#ifdef DM_LIST_VERSIONS
{"versions", DM_LIST_VERSIONS, {4, 1, 0}},
#endif
#ifdef DM_TARGET_MSG
{"message", DM_TARGET_MSG, {4, 2, 0}},
#endif
#ifdef DM_DEV_SET_GEOMETRY
{"setgeometry", DM_DEV_SET_GEOMETRY, {4, 6, 0}},
#endif
};
/* *INDENT-ON* */

#define ALIGNMENT_V1 sizeof(int)
#define ALIGNMENT 8

/* FIXME Rejig library to record & use errno instead */
#ifndef DM_EXISTS_FLAG
# define DM_EXISTS_FLAG 0x00000004
#endif

static void *_align(void *ptr, unsigned int a)
{
register unsigned long agn = --a;

return (void *) (((unsigned long) ptr + agn) & ~agn);
}

#ifdef DM_IOCTLS
/*
* Set number to NULL to populate _dm_bitset - otherwise first
* match is returned.
*/
static int _get_proc_number(const char *file, const char *name,
uint32_t *number)
{
FILE *fl;
char nm[256];
int c;
uint32_t num;

if (!(fl = fopen(file, "r"))) {
log_sys_error("fopen", file);
return 0;
}

while (!feof(fl)) {
if (fscanf(fl, "%d %255s\n", &num, &nm[0]) == 2) {
if (!strcmp(name, nm)) {
if (number) {
*number = num;
if (fclose(fl))
log_sys_error("fclose", file);
return 1;
}
dm_bit_set(_dm_bitset, num);
}
} else do {
c = fgetc(fl);
} while (c != EOF && c != '\n');
}
if (fclose(fl))
log_sys_error("fclose", file);

if (number) {
log_error("%s: No entry for %s found", file, name);
return 0;
}

return 1;
}

static int _control_device_number(uint32_t *major, uint32_t *minor)
{
if (!_get_proc_number(PROC_DEVICES, MISC_NAME, major) ||
!_get_proc_number(PROC_MISC, DM_NAME, minor)) {
*major = 0;
return 0;
}

return 1;
}

/*
* Returns 1 if exists; 0 if it doesn't; -1 if it's wrong
*/
static int _control_exists(const char *control, uint32_t major, uint32_t minor)
{
struct stat buf;

if (stat(control, &buf) < 0) {
if (errno != ENOENT)
log_sys_error("stat", control);
return 0;
}

if (!S_ISCHR(buf.st_mode)) {
log_verbose("%s: Wrong inode type", control);
if (!unlink(control))
return 0;
log_sys_error("unlink", control);
return -1;
}

if (major && buf.st_rdev != MKDEV(major, minor)) {
log_verbose("%s: Wrong device number: (%u, %u) instead of "
"(%u, %u)", control,
MAJOR(buf.st_mode), MINOR(buf.st_mode),
major, minor);
if (!unlink(control))
return 0;
log_sys_error("unlink", control);
return -1;
}

return 1;
}

static int _create_control(const char *control, uint32_t major, uint32_t minor)
{
int ret;
mode_t old_umask;

if (!major)
return 0;

old_umask = umask(DM_DEV_DIR_UMASK);
ret = dm_create_dir(dm_dir());
umask(old_umask);

if (!ret)
return 0;

log_verbose("Creating device %s (%u, %u)", control, major, minor);

old_umask = umask(0);
if (mknod(control, S_IFCHR | DM_DEVICE_MODE,
MKDEV(major, minor)) < 0) {
umask(old_umask);
log_sys_error("mknod", control);
return 0;
}
umask(old_umask);
if (chown(control, DM_DEVICE_UID, DM_DEVICE_GID) == -1) {
log_sys_error("cbown", control);
return 0;
}

#ifdef HAVE_SELINUX
if (!dm_set_selinux_context(control, S_IFCHR)) {
stack;
return 0;
}
#endif

return 1;
}
#endif

/*
* FIXME Update bitset in long-running process if dm claims new major numbers.
*/
static int _create_dm_bitset(void)
{
#ifdef DM_IOCTLS
struct utsname uts;

if (_dm_bitset || _dm_device_major)
return 1;

if (uname(&uts))
return 0;

/*
* 2.6 kernels are limited to one major number.
* Assume 2.4 kernels are patched not to.
* FIXME Check _dm_version and _dm_version_minor if 2.6 changes this.
*/
if (!strncmp(uts.release, "2.6.", 4))
_dm_multiple_major_support = 0;

if (!_dm_multiple_major_support) {
if (!_get_proc_number(PROC_DEVICES, DM_NAME, &_dm_device_major))
return 0;
return 1;
}

/* Multiple major numbers supported */
if (!(_dm_bitset = dm_bitset_create(NULL, NUMBER_OF_MAJORS)))
return 0;

if (!_get_proc_number(PROC_DEVICES, DM_NAME, NULL)) {
dm_bitset_destroy(_dm_bitset);
_dm_bitset = NULL;
return 0;
}

return 1;
#else
return 0;
#endif
}

int dm_is_dm_major(uint32_t major)
{
if (!_create_dm_bitset())
return 0;

if (_dm_multiple_major_support)
return dm_bit(_dm_bitset, major) ? 1 : 0;
else
return (major == _dm_device_major) ? 1 : 0;
}

static int _open_control(void)
{
#ifdef DM_IOCTLS
char control[PATH_MAX];
uint32_t major = 0, minor;

if (_control_fd != -1)
return 1;

snprintf(control, sizeof(control), "%s/control", dm_dir());

if (!_control_device_number(&major, &minor))
log_error("Is device-mapper driver missing from kernel?");

if (!_control_exists(control, major, minor) &&
!_create_control(control, major, minor))
goto error;

if ((_control_fd = open(control, O_RDWR)) < 0) {
log_sys_error("open", control);
goto error;
}

if (!_create_dm_bitset()) {
log_error("Failed to set up list of device-mapper major numbers");
return 0;
}

return 1;

error:
log_error("Failure to communicate with kernel device-mapper driver.");
return 0;
#else
return 1;
#endif
}

void dm_task_destroy(struct dm_task *dmt)
{
struct target *t, *n;

for (t = dmt->head; t; t = n) {
n = t->next;
dm_free(t->params);
dm_free(t->type);
dm_free(t);
}

if (dmt->dev_name)
dm_free(dmt->dev_name);

if (dmt->newname)
dm_free(dmt->newname);

if (dmt->message)
dm_free(dmt->message);

if (dmt->dmi.v4)
dm_free(dmt->dmi.v4);

if (dmt->uuid)
dm_free(dmt->uuid);

dm_free(dmt);
}

/*
* Protocol Version 1 compatibility functions.
*/

#ifdef DM_COMPAT

static int _dm_task_get_driver_version_v1(struct dm_task *dmt, char *version,
size_t size)
{
unsigned int *v;

if (!dmt->dmi.v1) {
version[0] = '\0';
return 0;
}

v = dmt->dmi.v1->version;
snprintf(version, size, "%u.%u.%u", v[0], v[1], v[2]);
return 1;
}

/* Unmarshall the target info returned from a status call */
static int _unmarshal_status_v1(struct dm_task *dmt, struct dm_ioctl_v1 *dmi)
{
char *outbuf = (char *) dmi + dmi->data_start;
char *outptr = outbuf;
int32_t i;
struct dm_target_spec_v1 *spec;

for (i = 0; i < dmi->target_count; i++) {
spec = (struct dm_target_spec_v1 *) outptr;

if (!dm_task_add_target(dmt, spec->sector_start,
(uint64_t) spec->length,
spec->target_type,
outptr + sizeof(*spec))) {
return 0;
}

outptr = outbuf + spec->next;
}

return 1;
}

static int _dm_format_dev_v1(char *buf, int bufsize, uint32_t dev_major,
uint32_t dev_minor)
{
int r;

if (bufsize < 8)
return 0;

r = snprintf(buf, bufsize, "%03x:%03x", dev_major, dev_minor);
if (r < 0 || r > bufsize - 1)
return 0;

return 1;
}

static int _dm_task_get_info_v1(struct dm_task *dmt, struct dm_info *info)
{
if (!dmt->dmi.v1)
return 0;

memset(info, 0, sizeof(*info));

info->exists = dmt->dmi.v1->flags & DM_EXISTS_FLAG ? 1 : 0;
if (!info->exists)
return 1;

info->suspended = dmt->dmi.v1->flags & DM_SUSPEND_FLAG ? 1 : 0;
info->read_only = dmt->dmi.v1->flags & DM_READONLY_FLAG ? 1 : 0;
info->target_count = dmt->dmi.v1->target_count;
info->open_count = dmt->dmi.v1->open_count;
info->event_nr = 0;
info->major = MAJOR(dmt->dmi.v1->dev);
info->minor = MINOR(dmt->dmi.v1->dev);
info->live_table = 1;
info->inactive_table = 0;

return 1;
}

static const char *_dm_task_get_name_v1(const struct dm_task *dmt)
{
return (dmt->dmi.v1->name);
}

static const char *_dm_task_get_uuid_v1(const struct dm_task *dmt)
{
return (dmt->dmi.v1->uuid);
}

static struct dm_deps *_dm_task_get_deps_v1(struct dm_task *dmt)
{
log_error("deps version 1 no longer supported by libdevmapper");
return NULL;
}

static struct dm_names *_dm_task_get_names_v1(struct dm_task *dmt)
{
return (struct dm_names *) (((void *) dmt->dmi.v1) +
dmt->dmi.v1->data_start);
}

static void *_add_target_v1(struct target *t, void *out, void *end)
{
void *out_sp = out;
struct dm_target_spec_v1 sp;
size_t sp_size = sizeof(struct dm_target_spec_v1);
int len;
const char no_space[] = "Ran out of memory building ioctl parameter";

out += sp_size;
if (out >= end) {
log_error(no_space);
return NULL;
}

sp.status = 0;
sp.sector_start = t->start;
sp.length = t->length;
strncpy(sp.target_type, t->type, sizeof(sp.target_type));

len = strlen(t->params);

if ((out + len + 1) >= end) {
log_error(no_space);

log_error("t->params= '%s'", t->params);
return NULL;
}
strcpy((char *) out, t->params);
out += len + 1;

/* align next block */
out = _align(out, ALIGNMENT_V1);

sp.next = out - out_sp;

memcpy(out_sp, &sp, sp_size);

return out;
}

static struct dm_ioctl_v1 *_flatten_v1(struct dm_task *dmt)
{
const size_t min_size = 16 * 1024;
const int (*version)[3];

struct dm_ioctl_v1 *dmi;
struct target *t;
size_t len = sizeof(struct dm_ioctl_v1);
void *b, *e;
int count = 0;

for (t = dmt->head; t; t = t->next) {
len += sizeof(struct dm_target_spec_v1);
len += strlen(t->params) + 1 + ALIGNMENT_V1;
count++;
}

if (count && dmt->newname) {
log_error("targets and newname are incompatible");
return NULL;
}

if (dmt->newname)
len += strlen(dmt->newname) + 1;

/*
* Give len a minimum size so that we have space to store
* dependencies or status information.
*/
if (len < min_size)
len = min_size;

if (!(dmi = dm_malloc(len)))
return NULL;

memset(dmi, 0, len);

version = &_cmd_data_v1[dmt->type].version;

dmi->version[0] = (*version)[0];
dmi->version[1] = (*version)[1];
dmi->version[2] = (*version)[2];

dmi->data_size = len;
dmi->data_start = sizeof(struct dm_ioctl_v1);

if (dmt->dev_name)
strncpy(dmi->name, dmt->dev_name, sizeof(dmi->name));

if (dmt->type == DM_DEVICE_SUSPEND)
dmi->flags |= DM_SUSPEND_FLAG;
if (dmt->read_only)
dmi->flags |= DM_READONLY_FLAG;

if (dmt->minor >= 0) {
if (dmt->major <= 0) {
log_error("Missing major number for persistent device");
return NULL;
}
dmi->flags |= DM_PERSISTENT_DEV_FLAG;
dmi->dev = MKDEV(dmt->major, dmt->minor);
}

if (dmt->uuid)
strncpy(dmi->uuid, dmt->uuid, sizeof(dmi->uuid));

dmi->target_count = count;

b = (void *) (dmi + 1);
e = (void *) ((char *) dmi + len);

for (t = dmt->head; t; t = t->next)
if (!(b = _add_target_v1(t, b, e)))
goto bad;

if (dmt->newname)
strcpy(b, dmt->newname);

return dmi;

bad:
dm_free(dmi);
return NULL;
}

static int _dm_names_v1(struct dm_ioctl_v1 *dmi)
{
const char *dev_dir = dm_dir();
int r = 1, len;
const char *name;
struct dirent *dirent;
DIR *d;
struct dm_names *names, *old_names = NULL;
void *end = (void *) dmi + dmi->data_size;
struct stat buf;
char path[PATH_MAX];

log_warn("WARNING: Device list may be incomplete with interface "
"version 1.");
log_warn("Please upgrade your kernel device-mapper driver.");

if (!(d = opendir(dev_dir))) {
log_sys_error("opendir", dev_dir);
return 0;
}

names = (struct dm_names *) ((void *) dmi + dmi->data_start);

names->dev = 0; /* Flags no data */

while ((dirent = readdir(d))) {
name = dirent->d_name;

if (name[0] == '.' || !strcmp(name, "control"))
continue;

if (old_names)
old_names->next = (uint32_t) ((void *) names -
(void *) old_names);
snprintf(path, sizeof(path), "%s/%s", dev_dir, name);
if (stat(path, &buf)) {
log_sys_error("stat", path);
continue;
}
if (!S_ISBLK(buf.st_mode))
continue;
names->dev = (uint64_t) buf.st_rdev;
names->next = 0;
len = strlen(name);
if (((void *) (names + 1) + len + 1) >= end) {
log_error("Insufficient buffer space for device list");
r = 0;
break;
}

strcpy(names->name, name);

old_names = names;
names = _align((void *) ++names + len + 1, ALIGNMENT);
}

if (closedir(d))
log_sys_error("closedir", dev_dir);

return r;
}

static int _dm_task_run_v1(struct dm_task *dmt)
{
struct dm_ioctl_v1 *dmi;
unsigned int command;

dmi = _flatten_v1(dmt);
if (!dmi) {
log_error("Couldn't create ioctl argument.");
return 0;
}

if (!_open_control())
return 0;

if ((unsigned) dmt->type >=
(sizeof(_cmd_data_v1) / sizeof(*_cmd_data_v1))) {
log_error("Internal error: unknown device-mapper task %d",
dmt->type);
goto bad;
}

command = _cmd_data_v1[dmt->type].cmd;

if (dmt->type == DM_DEVICE_TABLE)
dmi->flags |= DM_STATUS_TABLE_FLAG;

log_debug("dm %s %s %s%s%s [%u]", _cmd_data_v1[dmt->type].name,
dmi->name, dmi->uuid, dmt->newname ? " " : "",
dmt->newname ? dmt->newname : "",
dmi->data_size);
if (dmt->type == DM_DEVICE_LIST) {
if (!_dm_names_v1(dmi))
goto bad;
}
#ifdef DM_IOCTLS
else if (ioctl(_control_fd, command, dmi) < 0) {
if (_log_suppress)
log_verbose("device-mapper: %s ioctl failed: %s",
_cmd_data_v1[dmt->type].name,
strerror(errno));
else
log_error("device-mapper: %s ioctl failed: %s",
_cmd_data_v1[dmt->type].name,
strerror(errno));
goto bad;
}
#else /* Userspace alternative for testing */
#endif

if (dmi->flags & DM_BUFFER_FULL_FLAG)
/* FIXME Increase buffer size and retry operation (if query) */
log_error("WARNING: libdevmapper buffer too small for data");

switch (dmt->type) {
case DM_DEVICE_CREATE:
add_dev_node(dmt->dev_name, MAJOR(dmi->dev), MINOR(dmi->dev),
dmt->uid, dmt->gid, dmt->mode, 0);
break;

case DM_DEVICE_REMOVE:
rm_dev_node(dmt->dev_name, 0);
break;

case DM_DEVICE_RENAME:
rename_dev_node(dmt->dev_name, dmt->newname, 0);
break;

case DM_DEVICE_MKNODES:
if (dmi->flags & DM_EXISTS_FLAG)
add_dev_node(dmt->dev_name, MAJOR(dmi->dev),
MINOR(dmi->dev), dmt->uid,
dmt->gid, dmt->mode, 0);
else
rm_dev_node(dmt->dev_name, 0);
break;

case DM_DEVICE_STATUS:
case DM_DEVICE_TABLE:
if (!_unmarshal_status_v1(dmt, dmi))
goto bad;
break;

case DM_DEVICE_SUSPEND:
case DM_DEVICE_RESUME:
dmt->type = DM_DEVICE_INFO;
if (!dm_task_run(dmt))
goto bad;
dm_free(dmi); /* We'll use what info returned */
return 1;
}

dmt->dmi.v1 = dmi;
return 1;

bad:
dm_free(dmi);
return 0;
}

#endif

/*
* Protocol Version 4 functions.
*/

int dm_task_get_driver_version(struct dm_task *dmt, char *version, size_t size)
{
unsigned *v;

#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_task_get_driver_version_v1(dmt, version, size);
#endif

if (!dmt->dmi.v4) {
version[0] = '\0';
return 0;
}

v = dmt->dmi.v4->version;
snprintf(version, size, "%u.%u.%u", v[0], v[1], v[2]);
_dm_version_minor = v[1];
_dm_version_patchlevel = v[2];

return 1;
}

static int _check_version(char *version, size_t size, int log_suppress)
{
struct dm_task *task;
int r;

if (!(task = dm_task_create(DM_DEVICE_VERSION))) {
log_error("Failed to get device-mapper version");
version[0] = '\0';
return 0;
}

if (log_suppress)
_log_suppress = 1;

r = dm_task_run(task);
dm_task_get_driver_version(task, version, size);
dm_task_destroy(task);
_log_suppress = 0;

return r;
}

/*
* Find out device-mapper's major version number the first time
* this is called and whether or not we support it.
*/
int dm_check_version(void)
{
char libversion[64], dmversion[64];
const char *compat = "";

if (_version_checked)
return _version_ok;

_version_checked = 1;

if (_check_version(dmversion, sizeof(dmversion), _dm_compat))
return 1;

if (!_dm_compat)
goto bad;

log_verbose("device-mapper ioctl protocol version %u failed. "
"Trying protocol version 1.", _dm_version);
_dm_version = 1;
if (_check_version(dmversion, sizeof(dmversion), 0)) {
log_verbose("Using device-mapper ioctl protocol version 1");
return 1;
}

compat = "(compat)";

dm_get_library_version(libversion, sizeof(libversion));

log_error("Incompatible libdevmapper %s%s and kernel driver %s",
libversion, compat, dmversion);

bad:
_version_ok = 0;
return 0;
}

int dm_cookie_supported(void)
{
return (dm_check_version() &&
_dm_version >= 4 &&
_dm_version_minor >= 15);
}

void *dm_get_next_target(struct dm_task *dmt, void *next,
uint64_t *start, uint64_t *length,
char **target_type, char **params)
{
struct target *t = (struct target *) next;

if (!t)
t = dmt->head;

if (!t)
return NULL;

*start = t->start;
*length = t->length;
*target_type = t->type;
*params = t->params;

return t->next;
}

/* Unmarshall the target info returned from a status call */
static int _unmarshal_status(struct dm_task *dmt, struct dm_ioctl *dmi)
{
char *outbuf = (char *) dmi + dmi->data_start;
char *outptr = outbuf;
uint32_t i;
struct dm_target_spec *spec;

for (i = 0; i < dmi->target_count; i++) {
spec = (struct dm_target_spec *) outptr;
if (!dm_task_add_target(dmt, spec->sector_start,
spec->length,
spec->target_type,
outptr + sizeof(*spec))) {
return 0;
}

outptr = outbuf + spec->next;
}

return 1;
}

int dm_format_dev(char *buf, int bufsize, uint32_t dev_major,
uint32_t dev_minor)
{
int r;

#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_format_dev_v1(buf, bufsize, dev_major, dev_minor);
#endif

if (bufsize < 8)
return 0;

r = snprintf(buf, (size_t) bufsize, "%u:%u", dev_major, dev_minor);
if (r < 0 || r > bufsize - 1)
return 0;

return 1;
}

int dm_task_get_info(struct dm_task *dmt, struct dm_info *info)
{
#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_task_get_info_v1(dmt, info);
#endif

if (!dmt->dmi.v4)
return 0;

memset(info, 0, sizeof(*info));

info->exists = dmt->dmi.v4->flags & DM_EXISTS_FLAG ? 1 : 0;
if (!info->exists)
return 1;

info->suspended = dmt->dmi.v4->flags & DM_SUSPEND_FLAG ? 1 : 0;
info->read_only = dmt->dmi.v4->flags & DM_READONLY_FLAG ? 1 : 0;
info->live_table = dmt->dmi.v4->flags & DM_ACTIVE_PRESENT_FLAG ? 1 : 0;
info->inactive_table = dmt->dmi.v4->flags & DM_INACTIVE_PRESENT_FLAG ?
1 : 0;
info->target_count = dmt->dmi.v4->target_count;
info->open_count = dmt->dmi.v4->open_count;
info->event_nr = dmt->dmi.v4->event_nr;
info->major = MAJOR(dmt->dmi.v4->dev);
info->minor = MINOR(dmt->dmi.v4->dev);

return 1;
}

uint32_t dm_task_get_read_ahead(const struct dm_task *dmt, uint32_t *read_ahead)
{
const char *dev_name;

*read_ahead = 0;

#ifdef DM_COMPAT
/* Not supporting this */
if (_dm_version == 1)
return 1;
#endif

if (!dmt->dmi.v4 || !(dmt->dmi.v4->flags & DM_EXISTS_FLAG))
return 0;

if (*dmt->dmi.v4->name)
dev_name = dmt->dmi.v4->name;
else if (dmt->dev_name)
dev_name = dmt->dev_name;
else {
log_error("Get read ahead request failed: device name unrecorded.");
return 0;
}

return get_dev_node_read_ahead(dev_name, read_ahead);
}

const char *dm_task_get_name(const struct dm_task *dmt)
{
#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_task_get_name_v1(dmt);
#endif

return (dmt->dmi.v4->name);
}

const char *dm_task_get_uuid(const struct dm_task *dmt)
{
#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_task_get_uuid_v1(dmt);
#endif

return (dmt->dmi.v4->uuid);
}

struct dm_deps *dm_task_get_deps(struct dm_task *dmt)
{
#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_task_get_deps_v1(dmt);
#endif

return (struct dm_deps *) (((void *) dmt->dmi.v4) +
dmt->dmi.v4->data_start);
}

struct dm_names *dm_task_get_names(struct dm_task *dmt)
{
#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_task_get_names_v1(dmt);
#endif

return (struct dm_names *) (((void *) dmt->dmi.v4) +
dmt->dmi.v4->data_start);
}

struct dm_versions *dm_task_get_versions(struct dm_task *dmt)
{
return (struct dm_versions *) (((void *) dmt->dmi.v4) +
dmt->dmi.v4->data_start);
}

int dm_task_set_ro(struct dm_task *dmt)
{
dmt->read_only = 1;
return 1;
}

int dm_task_set_read_ahead(struct dm_task *dmt, uint32_t read_ahead,
uint32_t read_ahead_flags)
{
dmt->read_ahead = read_ahead;
dmt->read_ahead_flags = read_ahead_flags;

return 1;
}

int dm_task_suppress_identical_reload(struct dm_task *dmt)
{
dmt->suppress_identical_reload = 1;
return 1;
}

int dm_task_set_newname(struct dm_task *dmt, const char *newname)
{
if (strchr(newname, '/')) {
log_error("Name \"%s\" invalid. It contains \"/\".", newname);
return 0;
}

if (strlen(newname) >= DM_NAME_LEN) {
log_error("Name \"%s\" too long", newname);
return 0;
}

if (!(dmt->newname = dm_strdup(newname))) {
log_error("dm_task_set_newname: strdup(%s) failed", newname);
return 0;
}

return 1;
}

int dm_task_set_message(struct dm_task *dmt, const char *message)
{
if (!(dmt->message = dm_strdup(message))) {
log_error("dm_task_set_message: strdup(%s) failed", message);
return 0;
}

return 1;
}

int dm_task_set_sector(struct dm_task *dmt, uint64_t sector)
{
dmt->sector = sector;

return 1;
}

int dm_task_set_geometry(struct dm_task *dmt, const char *cylinders, const char *heads, const char *sectors, const char *start)
{
size_t len = strlen(cylinders) + 1 + strlen(heads) + 1 + strlen(sectors) + 1 + strlen(start) + 1;

if (!(dmt->geometry = dm_malloc(len))) {
log_error("dm_task_set_geometry: dm_malloc failed");
return 0;
}

if (sprintf(dmt->geometry, "%s %s %s %s", cylinders, heads, sectors, start) < 0) {
log_error("dm_task_set_geometry: sprintf failed");
return 0;
}

return 1;
}

int dm_task_no_flush(struct dm_task *dmt)
{
dmt->no_flush = 1;

return 1;
}

int dm_task_no_open_count(struct dm_task *dmt)
{
dmt->no_open_count = 1;

return 1;
}

int dm_task_skip_lockfs(struct dm_task *dmt)
{
dmt->skip_lockfs = 1;

return 1;
}

int dm_task_query_inactive_table(struct dm_task *dmt)
{
dmt->query_inactive_table = 1;

return 1;
}

int dm_task_set_event_nr(struct dm_task *dmt, uint32_t event_nr)
{
dmt->event_nr = event_nr;

return 1;
}

struct target *create_target(uint64_t start, uint64_t len, const char *type,
const char *params)
{
struct target *t = dm_malloc(sizeof(*t));

if (!t) {
log_error("create_target: malloc(%" PRIsize_t ") failed",
sizeof(*t));
return NULL;
}

memset(t, 0, sizeof(*t));

if (!(t->params = dm_strdup(params))) {
log_error("create_target: strdup(params) failed");
goto bad;
}

if (!(t->type = dm_strdup(type))) {
log_error("create_target: strdup(type) failed");
goto bad;
}

t->start = start;
t->length = len;
return t;

bad:
dm_free(t->params);
dm_free(t->type);
dm_free(t);
return NULL;
}

static void *_add_target(struct target *t, void *out, void *end)
{
void *out_sp = out;
struct dm_target_spec sp;
size_t sp_size = sizeof(struct dm_target_spec);
int len;
const char no_space[] = "Ran out of memory building ioctl parameter";

out += sp_size;
if (out >= end) {
log_error(no_space);
return NULL;
}

sp.status = 0;
sp.sector_start = t->start;
sp.length = t->length;
strncpy(sp.target_type, t->type, sizeof(sp.target_type));

len = strlen(t->params);

if ((out + len + 1) >= end) {
log_error(no_space);

log_error("t->params= '%s'", t->params);
return NULL;
}
strcpy((char *) out, t->params);
out += len + 1;

/* align next block */
out = _align(out, ALIGNMENT);

sp.next = out - out_sp;
memcpy(out_sp, &sp, sp_size);

return out;
}

static int _lookup_dev_name(uint64_t dev, char *buf, size_t len)
{
struct dm_names *names;
unsigned next = 0;
struct dm_task *dmt;
int r = 0;

if (!(dmt = dm_task_create(DM_DEVICE_LIST)))
return 0;

if (!dm_task_run(dmt))
goto out;

if (!(names = dm_task_get_names(dmt)))
goto out;

if (!names->dev)
goto out;

do {
names = (void *) names + next;
if (names->dev == dev) {
strncpy(buf, names->name, len);
r = 1;
break;
}
next = names->next;
} while (next);

out:
dm_task_destroy(dmt);
return r;
}

static struct dm_ioctl *_flatten(struct dm_task *dmt, unsigned repeat_count)
{
const size_t min_size = 16 * 1024;
const int (*version)[3];

struct dm_ioctl *dmi;
struct target *t;
struct dm_target_msg *tmsg;
size_t len = sizeof(struct dm_ioctl);
void *b, *e;
int count = 0;

for (t = dmt->head; t; t = t->next) {
len += sizeof(struct dm_target_spec);
len += strlen(t->params) + 1 + ALIGNMENT;
count++;
}

if (count && (dmt->sector || dmt->message)) {
log_error("targets and message are incompatible");
return NULL;
}

if (count && dmt->newname) {
log_error("targets and newname are incompatible");
return NULL;
}

if (count && dmt->geometry) {
log_error("targets and geometry are incompatible");
return NULL;
}

if (dmt->newname && (dmt->sector || dmt->message)) {
log_error("message and newname are incompatible");
return NULL;
}

if (dmt->newname && dmt->geometry) {
log_error("geometry and newname are incompatible");
return NULL;
}

if (dmt->geometry && (dmt->sector || dmt->message)) {
log_error("geometry and message are incompatible");
return NULL;
}

if (dmt->sector && !dmt->message) {
log_error("message is required with sector");
return NULL;
}

if (dmt->newname)
len += strlen(dmt->newname) + 1;

if (dmt->message)
len += sizeof(struct dm_target_msg) + strlen(dmt->message) + 1;

if (dmt->geometry)
len += strlen(dmt->geometry) + 1;

/*
* Give len a minimum size so that we have space to store
* dependencies or status information.
*/
if (len < min_size)
len = min_size;

/* Increase buffer size if repeating because buffer was too small */
while (repeat_count--)
len *= 2;

if (!(dmi = dm_malloc(len)))
return NULL;

memset(dmi, 0, len);

version = &_cmd_data_v4[dmt->type].version;

dmi->version[0] = (*version)[0];
dmi->version[1] = (*version)[1];
dmi->version[2] = (*version)[2];

dmi->data_size = len;
dmi->data_start = sizeof(struct dm_ioctl);

if (dmt->minor >= 0) {
if (dmt->major <= 0) {
log_error("Missing major number for persistent device.");
goto bad;
}

if (!_dm_multiple_major_support && dmt->allow_default_major_fallback &&
dmt->major != _dm_device_major) {
log_verbose("Overriding major number of %" PRIu32
" with %" PRIu32 " for persistent device.",
dmt->major, _dm_device_major);
dmt->major = _dm_device_major;
}

dmi->flags |= DM_PERSISTENT_DEV_FLAG;
dmi->dev = MKDEV(dmt->major, dmt->minor);
}

/* Does driver support device number referencing? */
if (_dm_version_minor < 3 && !dmt->dev_name && !dmt->uuid && dmi->dev) {
if (!_lookup_dev_name(dmi->dev, dmi->name, sizeof(dmi->name))) {
log_error("Unable to find name for device (%" PRIu32
":%" PRIu32 ")", dmt->major, dmt->minor);
goto bad;
}
log_verbose("device (%" PRIu32 ":%" PRIu32 ") is %s "
"for compatibility with old kernel",
dmt->major, dmt->minor, dmi->name);
}

/* FIXME Until resume ioctl supplies name, use dev_name for readahead */
if (dmt->dev_name && (dmt->type != DM_DEVICE_RESUME || dmt->minor < 0 ||
dmt->major < 0))
strncpy(dmi->name, dmt->dev_name, sizeof(dmi->name));

if (dmt->uuid)
strncpy(dmi->uuid, dmt->uuid, sizeof(dmi->uuid));

if (dmt->type == DM_DEVICE_SUSPEND)
dmi->flags |= DM_SUSPEND_FLAG;
if (dmt->no_flush)
dmi->flags |= DM_NOFLUSH_FLAG;
if (dmt->read_only)
dmi->flags |= DM_READONLY_FLAG;
if (dmt->skip_lockfs)
dmi->flags |= DM_SKIP_LOCKFS_FLAG;
if (dmt->query_inactive_table) {
if (_dm_version_minor < 16)
log_warn("WARNING: Inactive table query unsupported "
"by kernel. It will use live table.");
dmi->flags |= DM_QUERY_INACTIVE_TABLE_FLAG;
}

dmi->target_count = count;
dmi->event_nr = dmt->event_nr;

b = (void *) (dmi + 1);
e = (void *) ((char *) dmi + len);

for (t = dmt->head; t; t = t->next)
if (!(b = _add_target(t, b, e)))
goto bad;

if (dmt->newname)
strcpy(b, dmt->newname);

if (dmt->message) {
tmsg = (struct dm_target_msg *) b;
tmsg->sector = dmt->sector;
strcpy(tmsg->message, dmt->message);
}

if (dmt->geometry)
strcpy(b, dmt->geometry);

return dmi;

bad:
dm_free(dmi);
return NULL;
}

static int _process_mapper_dir(struct dm_task *dmt)
{
struct dirent *dirent;
DIR *d;
const char *dir;
int r = 1;

dir = dm_dir();
if (!(d = opendir(dir))) {
log_sys_error("opendir", dir);
return 0;
}

while ((dirent = readdir(d))) {
if (!strcmp(dirent->d_name, ".") ||
!strcmp(dirent->d_name, "..") ||
!strcmp(dirent->d_name, "control"))
continue;
dm_task_set_name(dmt, dirent->d_name);
dm_task_run(dmt);
}

if (closedir(d))
log_sys_error("closedir", dir);

return r;
}

static int _process_all_v4(struct dm_task *dmt)
{
struct dm_task *task;
struct dm_names *names;
unsigned next = 0;
int r = 1;

if (!(task = dm_task_create(DM_DEVICE_LIST)))
return 0;

if (!dm_task_run(task)) {
r = 0;
goto out;
}

if (!(names = dm_task_get_names(task))) {
r = 0;
goto out;
}

if (!names->dev)
goto out;

do {
names = (void *) names + next;
if (!dm_task_set_name(dmt, names->name)) {
r = 0;
goto out;
}
if (!dm_task_run(dmt))
r = 0;
next = names->next;
} while (next);

out:
dm_task_destroy(task);
return r;
}

static int _mknodes_v4(struct dm_task *dmt)
{
(void) _process_mapper_dir(dmt);

return _process_all_v4(dmt);
}

/*
* If an operation that uses a cookie fails, decrement the
* semaphore instead of udev.
*/
static int _udev_complete(struct dm_task *dmt)
{
uint32_t cookie;

if (dmt->cookie_set) {
/* strip flags from the cookie and use cookie magic instead */
cookie = (dmt->event_nr & ~DM_UDEV_FLAGS_MASK) |
(DM_COOKIE_MAGIC << DM_UDEV_FLAGS_SHIFT);
return dm_udev_complete(cookie);
}

return 1;
}

static int _create_and_load_v4(struct dm_task *dmt)
{
struct dm_task *task;
int r;

/* Use new task struct to create the device */
if (!(task = dm_task_create(DM_DEVICE_CREATE))) {
log_error("Failed to create device-mapper task struct");
_udev_complete(dmt);
return 0;
}

/* Copy across relevant fields */
if (dmt->dev_name && !dm_task_set_name(task, dmt->dev_name)) {
dm_task_destroy(task);
_udev_complete(dmt);
return 0;
}

if (dmt->uuid && !dm_task_set_uuid(task, dmt->uuid)) {
dm_task_destroy(task);
_udev_complete(dmt);
return 0;
}

task->major = dmt->major;
task->minor = dmt->minor;
task->uid = dmt->uid;
task->gid = dmt->gid;
task->mode = dmt->mode;
/* FIXME: Just for udev_check in dm_task_run. Can we avoid this? */
task->event_nr = dmt->event_nr & DM_UDEV_FLAGS_MASK;
task->cookie_set = dmt->cookie_set;

r = dm_task_run(task);
dm_task_destroy(task);
if (!r) {
_udev_complete(dmt);
return 0;
}

/* Next load the table */
if (!(task = dm_task_create(DM_DEVICE_RELOAD))) {
log_error("Failed to create device-mapper task struct");
_udev_complete(dmt);
return 0;
}

/* Copy across relevant fields */
if (dmt->dev_name && !dm_task_set_name(task, dmt->dev_name)) {
dm_task_destroy(task);
_udev_complete(dmt);
return 0;
}

task->read_only = dmt->read_only;
task->head = dmt->head;
task->tail = dmt->tail;

r = dm_task_run(task);

task->head = NULL;
task->tail = NULL;
dm_task_destroy(task);
if (!r) {
_udev_complete(dmt);
goto revert;
}

/* Use the original structure last so the info will be correct */
dmt->type = DM_DEVICE_RESUME;
dm_free(dmt->uuid);
dmt->uuid = NULL;

r = dm_task_run(dmt);

if (r)
return r;

revert:
dmt->type = DM_DEVICE_REMOVE;
dm_free(dmt->uuid);
dmt->uuid = NULL;
dmt->cookie_set = 0;

if (!dm_task_run(dmt))
log_error("Failed to revert device creation.");

return r;
}

uint64_t dm_task_get_existing_table_size(struct dm_task *dmt)
{
return dmt->existing_table_size;
}

static int _reload_with_suppression_v4(struct dm_task *dmt)
{
struct dm_task *task;
struct target *t1, *t2;
int r;

/* New task to get existing table information */
if (!(task = dm_task_create(DM_DEVICE_TABLE))) {
log_error("Failed to create device-mapper task struct");
return 0;
}

/* Copy across relevant fields */
if (dmt->dev_name && !dm_task_set_name(task, dmt->dev_name)) {
dm_task_destroy(task);
return 0;
}

if (dmt->uuid && !dm_task_set_uuid(task, dmt->uuid)) {
dm_task_destroy(task);
return 0;
}

task->major = dmt->major;
task->minor = dmt->minor;

r = dm_task_run(task);

if (!r) {
dm_task_destroy(task);
return r;
}

/* Store existing table size */
t2 = task->head;
while (t2 && t2->next)
t2 = t2->next;
dmt->existing_table_size = t2 ? t2->start + t2->length : 0;

if ((task->dmi.v4->flags & DM_READONLY_FLAG) ? 1 : 0 != dmt->read_only)
goto no_match;

t1 = dmt->head;
t2 = task->head;

while (t1 && t2) {
while (t2->params[strlen(t2->params) - 1] == ' ')
t2->params[strlen(t2->params) - 1] = '\0';
if ((t1->start != t2->start) ||
(t1->length != t2->length) ||
(strcmp(t1->type, t2->type)) ||
(strcmp(t1->params, t2->params)))
goto no_match;
t1 = t1->next;
t2 = t2->next;
}

if (!t1 && !t2) {
dmt->dmi.v4 = task->dmi.v4;
task->dmi.v4 = NULL;
dm_task_destroy(task);
return 1;
}

no_match:
dm_task_destroy(task);

/* Now do the original reload */
dmt->suppress_identical_reload = 0;
r = dm_task_run(dmt);

return r;
}

static struct dm_ioctl *_do_dm_ioctl(struct dm_task *dmt, unsigned command,
unsigned repeat_count)
{
struct dm_ioctl *dmi;

dmi = _flatten(dmt, repeat_count);
if (!dmi) {
log_error("Couldn't create ioctl argument.");
return NULL;
}

if (dmt->type == DM_DEVICE_TABLE)
dmi->flags |= DM_STATUS_TABLE_FLAG;

dmi->flags |= DM_EXISTS_FLAG; /* FIXME */

if (dmt->no_open_count)
dmi->flags |= DM_SKIP_BDGET_FLAG;

/*
* Prevent udev vs. libdevmapper race when processing nodes and
* symlinks. This can happen when the udev rules are installed and
* udev synchronisation code is enabled in libdevmapper but the
* software using libdevmapper does not make use of it (by not calling
* dm_task_set_cookie before). We need to instruct the udev rules not
* to be applied at all in this situation so we can gracefully fallback
* to libdevmapper's node and symlink creation code.
*/
if (dm_udev_get_sync_support() && !dmt->cookie_set &&
(dmt->type == DM_DEVICE_RESUME ||
dmt->type == DM_DEVICE_REMOVE ||
dmt->type == DM_DEVICE_RENAME)) {
log_debug("Cookie value is not set while trying to call "
"DM_DEVICE_RESUME, DM_DEVICE_REMOVE or DM_DEVICE_RENAME "
"ioctl. Please, consider using libdevmapper's udev "
"synchronisation interface or disable it explicitly "
"by calling dm_udev_set_sync_support(0).");
log_debug("Switching off device-mapper and all subsystem related "
"udev rules. Falling back to libdevmapper node creation.");
/*
* Disable general dm and subsystem rules but keep dm disk rules
* if not flagged out explicitly before. We need /dev/disk content
* for the software that expects it.
*/
dmi->event_nr |= (DM_UDEV_DISABLE_DM_RULES_FLAG |
DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG) <<
DM_UDEV_FLAGS_SHIFT;
}

log_debug("dm %s %s %s%s%s %s%.0d%s%.0d%s"
"%s%c%c%s%s %.0" PRIu64 " %s [%u]",
_cmd_data_v4[dmt->type].name,
dmi->name, dmi->uuid, dmt->newname ? " " : "",
dmt->newname ? dmt->newname : "",
dmt->major > 0 ? "(" : "",
dmt->major > 0 ? dmt->major : 0,
dmt->major > 0 ? ":" : "",
dmt->minor > 0 ? dmt->minor : 0,
dmt->major > 0 && dmt->minor == 0 ? "0" : "",
dmt->major > 0 ? ") " : "",
dmt->no_open_count ? 'N' : 'O',
dmt->no_flush ? 'N' : 'F',
dmt->skip_lockfs ? "S " : "",
dmt->query_inactive_table ? "I " : "",
dmt->sector, dmt->message ? dmt->message : "",
dmi->data_size);
#ifdef DM_IOCTLS
if (ioctl(_control_fd, command, dmi) < 0) {
if (errno == ENXIO && ((dmt->type == DM_DEVICE_INFO) ||
(dmt->type == DM_DEVICE_MKNODES) ||
(dmt->type == DM_DEVICE_STATUS)))
dmi->flags &= ~DM_EXISTS_FLAG; /* FIXME */
else {
if (_log_suppress)
log_verbose("device-mapper: %s ioctl "
"failed: %s",
_cmd_data_v4[dmt->type].name,
strerror(errno));
else
log_error("device-mapper: %s ioctl "
"failed: %s",
_cmd_data_v4[dmt->type].name,
strerror(errno));
dm_free(dmi);
return NULL;
}
}
#else /* Userspace alternative for testing */
#endif
return dmi;
}

void dm_task_update_nodes(void)
{
update_devs();
}

int dm_task_run(struct dm_task *dmt)
{
struct dm_ioctl *dmi;
unsigned command;
int check_udev;

#ifdef DM_COMPAT
if (_dm_version == 1)
return _dm_task_run_v1(dmt);
#endif

if ((unsigned) dmt->type >=
(sizeof(_cmd_data_v4) / sizeof(*_cmd_data_v4))) {
log_error("Internal error: unknown device-mapper task %d",
dmt->type);
return 0;
}

command = _cmd_data_v4[dmt->type].cmd;

/* Old-style creation had a table supplied */
if (dmt->type == DM_DEVICE_CREATE && dmt->head)
return _create_and_load_v4(dmt);

if (dmt->type == DM_DEVICE_MKNODES && !dmt->dev_name &&
!dmt->uuid && dmt->major <= 0)
return _mknodes_v4(dmt);

if ((dmt->type == DM_DEVICE_RELOAD) && dmt->suppress_identical_reload)
return _reload_with_suppression_v4(dmt);

if (!_open_control()) {
_udev_complete(dmt);
return 0;
}

/* FIXME Detect and warn if cookie set but should not be. */
repeat_ioctl:
if (!(dmi = _do_dm_ioctl(dmt, command, _ioctl_buffer_double_factor))) {
_udev_complete(dmt);
return 0;
}

if (dmi->flags & DM_BUFFER_FULL_FLAG) {
switch (dmt->type) {
case DM_DEVICE_LIST_VERSIONS:
case DM_DEVICE_LIST:
case DM_DEVICE_DEPS:
case DM_DEVICE_STATUS:
case DM_DEVICE_TABLE:
case DM_DEVICE_WAITEVENT:
_ioctl_buffer_double_factor++;
dm_free(dmi);
goto repeat_ioctl;
default:
log_error("WARNING: libdevmapper buffer too small for data");
}
}

check_udev = dmt->cookie_set &&
!(dmt->event_nr >> DM_UDEV_FLAGS_SHIFT &
DM_UDEV_DISABLE_DM_RULES_FLAG);

switch (dmt->type) {
case DM_DEVICE_CREATE:
if (dmt->dev_name && *dmt->dev_name)
add_dev_node(dmt->dev_name, MAJOR(dmi->dev),
MINOR(dmi->dev), dmt->uid, dmt->gid,
dmt->mode, check_udev);
break;
case DM_DEVICE_REMOVE:
/* FIXME Kernel needs to fill in dmi->name */
if (dmt->dev_name)
rm_dev_node(dmt->dev_name, check_udev);
break;

case DM_DEVICE_RENAME:
/* FIXME Kernel needs to fill in dmi->name */
if (dmt->dev_name)
rename_dev_node(dmt->dev_name, dmt->newname,
check_udev);
break;

case DM_DEVICE_RESUME:
/* FIXME Kernel needs to fill in dmi->name */
set_dev_node_read_ahead(dmt->dev_name, dmt->read_ahead,
dmt->read_ahead_flags);
break;

case DM_DEVICE_MKNODES:
if (dmi->flags & DM_EXISTS_FLAG)
add_dev_node(dmi->name, MAJOR(dmi->dev),
MINOR(dmi->dev), dmt->uid,
dmt->gid, dmt->mode, 0);
else if (dmt->dev_name)
rm_dev_node(dmt->dev_name, 0);
break;

case DM_DEVICE_STATUS:
case DM_DEVICE_TABLE:
case DM_DEVICE_WAITEVENT:
if (!_unmarshal_status(dmt, dmi))
goto bad;
break;
}

/* Was structure reused? */
if (dmt->dmi.v4)
dm_free(dmt->dmi.v4);
dmt->dmi.v4 = dmi;
return 1;

bad:
dm_free(dmi);
return 0;
}

void dm_lib_release(void)
{
if (_control_fd != -1) {
close(_control_fd);
_control_fd = -1;
}
update_devs();
}

void dm_pools_check_leaks(void);

void dm_lib_exit(void)
{
dm_lib_release();
if (_dm_bitset)
dm_bitset_destroy(_dm_bitset);
_dm_bitset = NULL;
dm_pools_check_leaks();
dm_dump_memory();
_version_ok = 1;
_version_checked = 0;
}