NetBSD-5.0.2/external/gpl2/libdevmapper/dist/lib/libdm-common.c
/*
* 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 "lib.h"
#include "libdm-targets.h"
#include "libdm-common.h"
#include "list.h"
#include "kdev_t.h"
#include <stdarg.h>
#include <sys/param.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <linux/dm-ioctl.h>
#ifdef linux
# include <linux/fs.h>
#endif
#ifdef HAVE_SELINUX
# include <selinux/selinux.h>
#endif
#define DEV_DIR "/dev/"
static char _dm_dir[PATH_MAX] = DEV_DIR DM_DIR;
static int _verbose = 0;
/*
* Library users can provide their own logging
* function.
*/
static void _default_log(int level, const char *file __attribute((unused)),
int line __attribute((unused)), const char *f, ...)
{
va_list ap;
int use_stderr = level & _LOG_STDERR;
level &= ~_LOG_STDERR;
if (level > _LOG_WARN && !_verbose)
return;
va_start(ap, f);
if (level < _LOG_WARN)
vfprintf(stderr, f, ap);
else
vfprintf(use_stderr ? stderr : stdout, f, ap);
va_end(ap);
if (level < _LOG_WARN)
fprintf(stderr, "\n");
else
fprintf(use_stderr ? stderr : stdout, "\n");
}
dm_log_fn dm_log = _default_log;
void dm_log_init(dm_log_fn fn)
{
if (fn)
dm_log = fn;
else
dm_log = _default_log;
}
void dm_log_init_verbose(int level)
{
_verbose = level;
}
static void _build_dev_path(char *buffer, size_t len, const char *dev_name)
{
/* If there's a /, assume caller knows what they're doing */
if (strchr(dev_name, '/'))
snprintf(buffer, len, "%s", dev_name);
else
snprintf(buffer, len, "%s/%s", _dm_dir, dev_name);
}
int dm_get_library_version(char *version, size_t size)
{
strncpy(version, DM_LIB_VERSION, size);
return 1;
}
struct dm_task *dm_task_create(int type)
{
struct dm_task *dmt = dm_malloc(sizeof(*dmt));
if (!dmt) {
log_error("dm_task_create: malloc(%" PRIsize_t ") failed",
sizeof(*dmt));
return NULL;
}
if (!dm_check_version()) {
dm_free(dmt);
return NULL;
}
memset(dmt, 0, sizeof(*dmt));
dmt->type = type;
dmt->minor = -1;
dmt->major = -1;
dmt->uid = DM_DEVICE_UID;
dmt->gid = DM_DEVICE_GID;
dmt->mode = DM_DEVICE_MODE;
dmt->no_open_count = 0;
dmt->read_ahead = DM_READ_AHEAD_AUTO;
dmt->read_ahead_flags = 0;
return dmt;
}
int dm_task_set_name(struct dm_task *dmt, const char *name)
{
char *pos;
char path[PATH_MAX];
struct stat st1, st2;
if (dmt->dev_name) {
dm_free(dmt->dev_name);
dmt->dev_name = NULL;
}
/* If path was supplied, remove it if it points to the same device
* as its last component.
*/
if ((pos = strrchr(name, '/'))) {
snprintf(path, sizeof(path), "%s/%s", _dm_dir, pos + 1);
if (stat(name, &st1) || stat(path, &st2) ||
!(st1.st_dev == st2.st_dev)) {
log_error("dm_task_set_name: Device %s not found",
name);
return 0;
}
name = pos + 1;
}
if (!(dmt->dev_name = dm_strdup(name))) {
log_error("dm_task_set_name: strdup(%s) failed", name);
return 0;
}
return 1;
}
int dm_task_set_uuid(struct dm_task *dmt, const char *uuid)
{
if (dmt->uuid) {
dm_free(dmt->uuid);
dmt->uuid = NULL;
}
if (!(dmt->uuid = dm_strdup(uuid))) {
log_error("dm_task_set_uuid: strdup(%s) failed", uuid);
return 0;
}
return 1;
}
int dm_task_set_major(struct dm_task *dmt, int major)
{
dmt->major = major;
return 1;
}
int dm_task_set_minor(struct dm_task *dmt, int minor)
{
dmt->minor = minor;
return 1;
}
int dm_task_set_uid(struct dm_task *dmt, uid_t uid)
{
dmt->uid = uid;
return 1;
}
int dm_task_set_gid(struct dm_task *dmt, gid_t gid)
{
dmt->gid = gid;
return 1;
}
int dm_task_set_mode(struct dm_task *dmt, mode_t mode)
{
dmt->mode = mode;
return 1;
}
int dm_task_add_target(struct dm_task *dmt, uint64_t start, uint64_t size,
const char *ttype, const char *params)
{
struct target *t = create_target(start, size, ttype, params);
if (!t)
return 0;
if (!dmt->head)
dmt->head = dmt->tail = t;
else {
dmt->tail->next = t;
dmt->tail = t;
}
return 1;
}
#ifdef HAVE_SELINUX
int dm_set_selinux_context(const char *path, mode_t mode)
{
security_context_t scontext;
if (is_selinux_enabled() <= 0)
return 1;
if (matchpathcon(path, mode, &scontext) < 0) {
log_error("%s: matchpathcon %07o failed: %s", path, mode,
strerror(errno));
return 0;
}
log_debug("Setting SELinux context for %s to %s.", path, scontext);
if ((lsetfilecon(path, scontext) < 0) && (errno != ENOTSUP)) {
log_sys_error("lsetfilecon", path);
freecon(scontext);
return 0;
}
freecon(scontext);
return 1;
}
#endif
static int _add_dev_node(const char *dev_name, uint32_t major, uint32_t minor,
uid_t uid, gid_t gid, mode_t mode)
{
char path[PATH_MAX];
struct stat info;
dev_t dev = MKDEV(major, minor);
mode_t old_mask;
_build_dev_path(path, sizeof(path), dev_name);
if (stat(path, &info) >= 0) {
if (!S_ISBLK(info.st_mode)) {
log_error("A non-block device file at '%s' "
"is already present", path);
return 0;
}
/* If right inode already exists we don't touch uid etc. */
if (info.st_rdev == dev)
return 1;
if (unlink(path) < 0) {
log_error("Unable to unlink device node for '%s'",
dev_name);
return 0;
}
}
old_mask = umask(0);
if (mknod(path, S_IFBLK | mode, dev) < 0) {
log_error("Unable to make device node for '%s'", dev_name);
return 0;
}
umask(old_mask);
if (chown(path, uid, gid) < 0) {
log_sys_error("chown", path);
return 0;
}
log_debug("Created %s", path);
#ifdef HAVE_SELINUX
if (!dm_set_selinux_context(path, S_IFBLK))
return 0;
#endif
return 1;
}
static int _rename_dev_node(const char *old_name, const char *new_name)
{
char oldpath[PATH_MAX];
char newpath[PATH_MAX];
struct stat info;
_build_dev_path(oldpath, sizeof(oldpath), old_name);
_build_dev_path(newpath, sizeof(newpath), new_name);
if (stat(newpath, &info) == 0) {
if (!S_ISBLK(info.st_mode)) {
log_error("A non-block device file at '%s' "
"is already present", newpath);
return 0;
}
if (unlink(newpath) < 0) {
if (errno == EPERM) {
/* devfs, entry has already been renamed */
return 1;
}
log_error("Unable to unlink device node for '%s'",
new_name);
return 0;
}
}
if (rename(oldpath, newpath) < 0) {
log_error("Unable to rename device node from '%s' to '%s'",
old_name, new_name);
return 0;
}
log_debug("Renamed %s to %s", oldpath, newpath);
return 1;
}
static int _rm_dev_node(const char *dev_name)
{
char path[PATH_MAX];
struct stat info;
_build_dev_path(path, sizeof(path), dev_name);
if (stat(path, &info) < 0)
return 1;
if (unlink(path) < 0) {
log_error("Unable to unlink device node for '%s'", dev_name);
return 0;
}
log_debug("Removed %s", path);
return 1;
}
#ifdef linux
static int _open_dev_node(const char *dev_name)
{
int fd = -1;
char path[PATH_MAX];
_build_dev_path(path, sizeof(path), dev_name);
if ((fd = open(path, O_RDONLY, 0)) < 0)
log_sys_error("open", path);
return fd;
}
int get_dev_node_read_ahead(const char *dev_name, uint32_t *read_ahead)
{
int r = 1;
int fd;
long read_ahead_long;
if (!*dev_name) {
log_error("Empty device name passed to BLKRAGET");
return 0;
}
if ((fd = _open_dev_node(dev_name)) < 0)
return_0;
if (ioctl(fd, BLKRAGET, &read_ahead_long)) {
log_sys_error("BLKRAGET", dev_name);
*read_ahead = 0;
r = 0;
} else {
*read_ahead = (uint32_t) read_ahead_long;
log_debug("%s: read ahead is %" PRIu32, dev_name, *read_ahead);
}
if (close(fd))
stack;
return r;
}
static int _set_read_ahead(const char *dev_name, uint32_t read_ahead)
{
int r = 1;
int fd;
long read_ahead_long = (long) read_ahead;
if (!*dev_name) {
log_error("Empty device name passed to BLKRAGET");
return 0;
}
if ((fd = _open_dev_node(dev_name)) < 0)
return_0;
log_debug("%s: Setting read ahead to %" PRIu32, dev_name, read_ahead);
if (ioctl(fd, BLKRASET, read_ahead_long)) {
log_sys_error("BLKRASET", dev_name);
r = 0;
}
if (close(fd))
stack;
return r;
}
static int _set_dev_node_read_ahead(const char *dev_name, uint32_t read_ahead,
uint32_t read_ahead_flags)
{
uint32_t current_read_ahead;
if (read_ahead == DM_READ_AHEAD_AUTO)
return 1;
if (read_ahead == DM_READ_AHEAD_NONE)
read_ahead = 0;
if (read_ahead_flags & DM_READ_AHEAD_MINIMUM_FLAG) {
if (!get_dev_node_read_ahead(dev_name, ¤t_read_ahead))
return_0;
if (current_read_ahead > read_ahead) {
log_debug("%s: retaining kernel read ahead of %" PRIu32
" (requested %" PRIu32 ")",
dev_name, current_read_ahead, read_ahead);
return 1;
}
}
return _set_read_ahead(dev_name, read_ahead);
}
#else
int get_dev_node_read_ahead(const char *dev_name, uint32_t *read_ahead)
{
*read_ahead = 0;
return 1;
}
static int _set_dev_node_read_ahead(const char *dev_name, uint32_t read_ahead,
uint32_t read_ahead_flags)
{
return 1;
}
#endif
typedef enum {
NODE_ADD,
NODE_DEL,
NODE_RENAME,
NODE_READ_AHEAD
} node_op_t;
static int _do_node_op(node_op_t type, const char *dev_name, uint32_t major,
uint32_t minor, uid_t uid, gid_t gid, mode_t mode,
const char *old_name, uint32_t read_ahead,
uint32_t read_ahead_flags)
{
switch (type) {
case NODE_ADD:
return _add_dev_node(dev_name, major, minor, uid, gid, mode);
case NODE_DEL:
return _rm_dev_node(dev_name);
case NODE_RENAME:
return _rename_dev_node(old_name, dev_name);
case NODE_READ_AHEAD:
return _set_dev_node_read_ahead(dev_name, read_ahead,
read_ahead_flags);
}
return 1;
}
static LIST_INIT(_node_ops);
struct node_op_parms {
struct list list;
node_op_t type;
char *dev_name;
uint32_t major;
uint32_t minor;
uid_t uid;
gid_t gid;
mode_t mode;
uint32_t read_ahead;
uint32_t read_ahead_flags;
char *old_name;
char names[0];
};
static void _store_str(char **pos, char **ptr, const char *str)
{
strcpy(*pos, str);
*ptr = *pos;
*pos += strlen(*ptr) + 1;
}
static int _stack_node_op(node_op_t type, const char *dev_name, uint32_t major,
uint32_t minor, uid_t uid, gid_t gid, mode_t mode,
const char *old_name, uint32_t read_ahead,
uint32_t read_ahead_flags)
{
struct node_op_parms *nop;
struct list *noph, *nopht;
size_t len = strlen(dev_name) + strlen(old_name) + 2;
char *pos;
/*
* Ignore any outstanding operations on the node if deleting it
*/
if (type == NODE_DEL) {
list_iterate_safe(noph, nopht, &_node_ops) {
nop = list_item(noph, struct node_op_parms);
if (!strcmp(dev_name, nop->dev_name)) {
list_del(&nop->list);
dm_free(nop);
}
}
}
if (!(nop = dm_malloc(sizeof(*nop) + len))) {
log_error("Insufficient memory to stack mknod operation");
return 0;
}
pos = nop->names;
nop->type = type;
nop->major = major;
nop->minor = minor;
nop->uid = uid;
nop->gid = gid;
nop->mode = mode;
nop->read_ahead = read_ahead;
nop->read_ahead_flags = read_ahead_flags;
_store_str(&pos, &nop->dev_name, dev_name);
_store_str(&pos, &nop->old_name, old_name);
list_add(&_node_ops, &nop->list);
return 1;
}
static void _pop_node_ops(void)
{
struct list *noph, *nopht;
struct node_op_parms *nop;
list_iterate_safe(noph, nopht, &_node_ops) {
nop = list_item(noph, struct node_op_parms);
_do_node_op(nop->type, nop->dev_name, nop->major, nop->minor,
nop->uid, nop->gid, nop->mode, nop->old_name,
nop->read_ahead, nop->read_ahead_flags);
list_del(&nop->list);
dm_free(nop);
}
}
int add_dev_node(const char *dev_name, uint32_t major, uint32_t minor,
uid_t uid, gid_t gid, mode_t mode)
{
log_debug("%s: Stacking NODE_ADD (%" PRIu32 ",%" PRIu32 ") %u:%u 0%o",
dev_name, major, minor, uid, gid, mode);
return _stack_node_op(NODE_ADD, dev_name, major, minor, uid, gid, mode,
"", 0, 0);
}
int rename_dev_node(const char *old_name, const char *new_name)
{
log_debug("%s: Stacking NODE_RENAME to %s", old_name, new_name);
return _stack_node_op(NODE_RENAME, new_name, 0, 0, 0, 0, 0, old_name,
0, 0);
}
int rm_dev_node(const char *dev_name)
{
log_debug("%s: Stacking NODE_DEL (replaces other stacked ops)", dev_name);
return _stack_node_op(NODE_DEL, dev_name, 0, 0, 0, 0, 0, "", 0, 0);
}
int set_dev_node_read_ahead(const char *dev_name, uint32_t read_ahead,
uint32_t read_ahead_flags)
{
if (read_ahead == DM_READ_AHEAD_AUTO)
return 1;
log_debug("%s: Stacking NODE_READ_AHEAD %" PRIu32 " (flags=%" PRIu32
")", dev_name, read_ahead, read_ahead_flags);
return _stack_node_op(NODE_READ_AHEAD, dev_name, 0, 0, 0, 0, 0, "",
read_ahead, read_ahead_flags);
}
void update_devs(void)
{
_pop_node_ops();
}
int dm_set_dev_dir(const char *dev_dir)
{
size_t len;
const char *slash;
if (*dev_dir != '/') {
log_debug("Invalid dev_dir value, %s: "
"not an absolute name.", dev_dir);
return 0;
}
len = strlen(dev_dir);
slash = dev_dir[len-1] == '/' ? "" : "/";
if (snprintf(_dm_dir, sizeof _dm_dir, "%s%s%s", dev_dir, slash, DM_DIR)
>= sizeof _dm_dir) {
log_debug("Invalid dev_dir value, %s: name too long.", dev_dir);
return 0;
}
return 1;
}
const char *dm_dir(void)
{
return _dm_dir;
}
int dm_mknodes(const char *name)
{
struct dm_task *dmt;
int r = 0;
if (!(dmt = dm_task_create(DM_DEVICE_MKNODES)))
return 0;
if (name && !dm_task_set_name(dmt, name))
goto out;
if (!dm_task_no_open_count(dmt))
goto out;
r = dm_task_run(dmt);
out:
dm_task_destroy(dmt);
return r;
}
int dm_driver_version(char *version, size_t size)
{
struct dm_task *dmt;
int r = 0;
if (!(dmt = dm_task_create(DM_DEVICE_VERSION)))
return 0;
if (!dm_task_run(dmt))
log_error("Failed to get driver version");
if (!dm_task_get_driver_version(dmt, version, size))
goto out;
r = 1;
out:
dm_task_destroy(dmt);
return r;
}