1 /* $NetBSD: libdm-common.c,v 1.5 2009/12/05 11:42:24 haad Exp $ */
4 * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
5 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
7 * This file is part of the device-mapper userspace tools.
9 * This copyrighted material is made available to anyone wishing to use,
10 * modify, copy, or redistribute it subject to the terms and conditions
11 * of the GNU Lesser General Public License v.2.1.
13 * You should have received a copy of the GNU Lesser General Public License
14 * along with this program; if not, write to the Free Software Foundation,
15 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include "libdm-targets.h"
20 #include "libdm-common.h"
27 #include <sys/param.h>
28 #include <sys/ioctl.h>
32 #ifdef UDEV_SYNC_SUPPORT
33 # include <sys/types.h>
36 #ifdef HAVE_UDEV_QUEUE_GET_UDEV_IS_ACTIVE
37 # define LIBUDEV_I_KNOW_THE_API_IS_SUBJECT_TO_CHANGE
43 # include <linux/fs.h>
47 # include <selinux/selinux.h>
50 #if defined(__NetBSD__) || defined(__DragonFly__)
51 #include "libdm-netbsd.h"
54 #define DEV_DIR "/dev/"
56 static char _dm_dir[PATH_MAX] = DEV_DIR DM_DIR;
58 static int _verbose = 0;
60 #ifdef UDEV_SYNC_SUPPORT
61 static int _udev_running = -1;
62 static int _sync_with_udev = 1;
66 * Library users can provide their own logging
70 static void _default_log_line(int level,
71 const char *file __attribute((unused)),
72 int line __attribute((unused)), int dm_errno,
73 const char *f, va_list ap)
75 int use_stderr = level & _LOG_STDERR;
77 level &= ~_LOG_STDERR;
79 if (level > _LOG_WARN && !_verbose)
82 if (level < _LOG_WARN)
83 vfprintf(stderr, f, ap);
85 vfprintf(use_stderr ? stderr : stdout, f, ap);
87 if (level < _LOG_WARN)
88 fprintf(stderr, "\n");
90 fprintf(use_stderr ? stderr : stdout, "\n");
93 static void _default_log_with_errno(int level,
94 const char *file __attribute((unused)),
95 int line __attribute((unused)), int dm_errno,
101 _default_log_line(level, file, line, dm_errno, f, ap);
105 static void _default_log(int level, const char *file,
106 int line, const char *f, ...)
111 _default_log_line(level, file, line, 0, f, ap);
115 dm_log_fn dm_log = _default_log;
116 dm_log_with_errno_fn dm_log_with_errno = _default_log_with_errno;
118 void dm_log_init(dm_log_fn fn)
123 dm_log = _default_log;
125 dm_log_with_errno = _default_log_with_errno;
128 int dm_log_is_non_default(void)
130 return (dm_log == _default_log) ? 0 : 1;
133 void dm_log_with_errno_init(dm_log_with_errno_fn fn)
136 dm_log_with_errno = fn;
138 dm_log_with_errno = _default_log_with_errno;
140 dm_log = _default_log;
143 void dm_log_init_verbose(int level)
148 static void _build_dev_path(char *buffer, size_t len, const char *dev_name)
150 /* If there's a /, assume caller knows what they're doing */
151 if (strchr(dev_name, '/'))
152 snprintf(buffer, len, "%s", dev_name);
154 snprintf(buffer, len, "%s/%s", _dm_dir, dev_name);
157 int dm_get_library_version(char *version, size_t size)
159 strncpy(version, DM_LIB_VERSION, size);
163 struct dm_task *dm_task_create(int type)
165 struct dm_task *dmt = dm_malloc(sizeof(*dmt));
168 log_error("dm_task_create: malloc(%" PRIsize_t ") failed",
173 if (!dm_check_version()) {
178 memset(dmt, 0, sizeof(*dmt));
183 dmt->allow_default_major_fallback = 1;
184 dmt->uid = DM_DEVICE_UID;
185 dmt->gid = DM_DEVICE_GID;
186 dmt->mode = DM_DEVICE_MODE;
187 dmt->no_open_count = 0;
188 dmt->read_ahead = DM_READ_AHEAD_AUTO;
189 dmt->read_ahead_flags = 0;
192 dmt->query_inactive_table = 0;
198 * Find the name associated with a given device number by scanning _dm_dir.
200 static char *_find_dm_name_of_device(dev_t st_rdev)
204 struct dirent *dirent;
207 char *new_name = NULL;
209 if (!(d = opendir(_dm_dir))) {
210 log_sys_error("opendir", _dm_dir);
214 while ((dirent = readdir(d))) {
215 name = dirent->d_name;
217 if (!strcmp(name, ".") || !strcmp(name, ".."))
220 if (dm_snprintf(path, sizeof(path), "%s/%s", _dm_dir,
222 log_error("Couldn't create path for %s", name);
226 if (stat(path, &buf))
229 if (buf.st_rdev == st_rdev) {
230 if (!(new_name = dm_strdup(name)))
231 log_error("dm_task_set_name: strdup(%s) failed",
238 log_sys_error("closedir", _dm_dir);
243 int dm_task_set_name(struct dm_task *dmt, const char *name)
246 char *new_name = NULL;
248 struct stat st1, st2;
251 dm_free(dmt->dev_name);
252 dmt->dev_name = NULL;
256 * Path supplied for existing device?
258 if ((pos = strrchr(name, '/'))) {
259 if (dmt->type == DM_DEVICE_CREATE) {
260 log_error("Name \"%s\" invalid. It contains \"/\".", name);
264 if (stat(name, &st1)) {
265 log_error("Device %s not found", name);
270 * If supplied path points to same device as last component
271 * under /dev/mapper, use that name directly. Otherwise call
272 * _find_dm_name_of_device() to scan _dm_dir for a match.
274 if (dm_snprintf(path, sizeof(path), "%s/%s", _dm_dir,
276 log_error("Couldn't create path for %s", pos + 1);
280 if (!stat(path, &st2) && (st1.st_rdev == st2.st_rdev))
282 else if ((new_name = _find_dm_name_of_device(st1.st_rdev)))
285 log_error("Device %s not found", name);
290 if (strlen(name) >= DM_NAME_LEN) {
291 log_error("Name \"%s\" too long", name);
298 dmt->dev_name = new_name;
299 else if (!(dmt->dev_name = dm_strdup(name))) {
300 log_error("dm_task_set_name: strdup(%s) failed", name);
307 int dm_task_set_uuid(struct dm_task *dmt, const char *uuid)
314 if (!(dmt->uuid = dm_strdup(uuid))) {
315 log_error("dm_task_set_uuid: strdup(%s) failed", uuid);
322 int dm_task_set_major(struct dm_task *dmt, int major)
325 dmt->allow_default_major_fallback = 0;
330 int dm_task_set_minor(struct dm_task *dmt, int minor)
337 int dm_task_set_major_minor(struct dm_task *dmt, int major, int minor,
338 int allow_default_major_fallback)
342 dmt->allow_default_major_fallback = allow_default_major_fallback;
347 int dm_task_set_uid(struct dm_task *dmt, uid_t uid)
354 int dm_task_set_gid(struct dm_task *dmt, gid_t gid)
361 int dm_task_set_mode(struct dm_task *dmt, mode_t mode)
368 int dm_task_add_target(struct dm_task *dmt, uint64_t start, uint64_t size,
369 const char *ttype, const char *params)
371 struct target *t = create_target(start, size, ttype, params);
377 dmt->head = dmt->tail = t;
386 int dm_set_selinux_context(const char *path, mode_t mode)
389 security_context_t scontext;
391 if (is_selinux_enabled() <= 0)
394 if (matchpathcon(path, mode, &scontext) < 0) {
395 log_error("%s: matchpathcon %07o failed: %s", path, mode,
400 log_debug("Setting SELinux context for %s to %s.", path, scontext);
402 if ((lsetfilecon(path, scontext) < 0) && (errno != ENOTSUP)) {
403 log_sys_error("lsetfilecon", path);
413 static int _add_dev_node(const char *dev_name, uint32_t major, uint32_t minor,
414 uid_t uid, gid_t gid, mode_t mode, int check_udev)
418 dev_t dev = MKDEV(major, minor);
422 char rpath[PATH_MAX];
425 char raw_devname[DM_NAME_LEN+1]; /* r + other device name */
427 nbsd_get_dm_major(&raw_major,DM_CHAR_MAJOR);
428 rdev = MKDEV(raw_major,minor);
430 snprintf(raw_devname,sizeof(raw_devname),"r%s",dev_name);
432 _build_dev_path(rpath, sizeof(rpath), raw_devname);
434 if (stat(rpath, &info) >= 0) {
435 if (!S_ISCHR(info.st_mode)) {
436 log_error("A non-raw device file at '%s' "
437 "is already present", rpath);
441 /* If right inode already exists we don't touch uid etc. */
442 if (info.st_rdev == rdev)
445 if (unlink(rpath) < 0) {
446 log_error("Unable to unlink device node for '%s'",
454 if (mknod(rpath, S_IFCHR | mode, rdev) < 0) {
455 log_error("Unable to make device node for '%s'", raw_devname);
458 #elif defined(__DragonFly__)
459 _build_dev_path(path, sizeof(path), dev_name);
460 log_error("Skipping all sanity checks here");
464 _build_dev_path(path, sizeof(path), dev_name);
466 if (stat(path, &info) >= 0) {
467 if (!S_ISBLK(info.st_mode)) {
468 log_error("A non-block device file at '%s' "
469 "is already present", path);
473 /* If right inode already exists we don't touch uid etc. */
474 if (info.st_rdev == dev)
477 if (unlink(path) < 0) {
478 log_error("Unable to unlink device node for '%s'",
482 } else if (dm_udev_get_sync_support() && check_udev)
483 log_warn("%s not set up by udev: Falling back to direct "
484 "node creation.", path);
487 if (mknod(path, S_IFBLK | mode, dev) < 0) {
489 log_error("Unable to make device node for '%s'", dev_name);
494 if (chown(path, uid, gid) < 0) {
495 log_sys_error("chown", path);
499 log_debug("Created %s", path);
501 if (!dm_set_selinux_context(path, S_IFBLK))
507 static int _rm_dev_node(const char *dev_name, int check_udev)
513 char rpath[PATH_MAX];
514 char raw_devname[DM_NAME_LEN+1]; /* r + other device name */
516 snprintf(raw_devname,sizeof(raw_devname),"r%s",dev_name);
518 _build_dev_path(rpath, sizeof(rpath), raw_devname);
520 if (stat(rpath, &info) < 0)
523 if (unlink(rpath) < 0) {
524 log_error("Unable to unlink device node for '%s'", raw_devname);
528 log_debug("Removed %s", rpath);
531 _build_dev_path(path, sizeof(path), dev_name);
533 if (stat(path, &info) < 0)
535 else if (dm_udev_get_sync_support() && check_udev)
536 log_warn("Node %s was not removed by udev. "
537 "Falling back to direct node removal.", path);
539 if (unlink(path) < 0) {
540 log_error("Unable to unlink device node for '%s'", dev_name);
544 log_debug("Removed %s", path);
549 static int _rename_dev_node(const char *old_name, const char *new_name,
552 char oldpath[PATH_MAX];
553 char newpath[PATH_MAX];
557 char rpath[PATH_MAX];
558 char nrpath[PATH_MAX];
559 char raw_devname[DM_NAME_LEN+1]; /* r + other device name */
560 char nraw_devname[DM_NAME_LEN+1]; /* r + other device name */
562 snprintf(nraw_devname,sizeof(raw_devname),"r%s",new_name);
563 snprintf(raw_devname,sizeof(raw_devname),"r%s",old_name);
565 _build_dev_path(nrpath, sizeof(nrpath), nraw_devname);
566 _build_dev_path(rpath, sizeof(rpath), raw_devname);
568 if (stat(nrpath, &info) == 0) {
569 if (S_ISBLK(info.st_mode)) {
570 log_error("A block device file at '%s' "
571 "is present where raw device should be.", newpath);
575 if (unlink(nrpath) < 0) {
576 log_error("Unable to unlink device node for '%s'",
582 if (rename(rpath, nrpath) < 0) {
583 log_error("Unable to rename device node from '%s' to '%s'",
584 raw_devname, nraw_devname);
588 log_debug("Renamed %s to %s", rpath, nrpath);
592 _build_dev_path(oldpath, sizeof(oldpath), old_name);
593 _build_dev_path(newpath, sizeof(newpath), new_name);
595 if (stat(newpath, &info) == 0) {
596 if (!S_ISBLK(info.st_mode)) {
597 log_error("A non-block device file at '%s' "
598 "is already present", newpath);
601 else if (dm_udev_get_sync_support() && check_udev) {
602 if (stat(oldpath, &info) < 0 &&
604 /* assume udev already deleted this */
607 log_warn("The node %s should have been renamed to %s "
608 "by udev but old node is still present. "
609 "Falling back to direct old node removal.",
611 return _rm_dev_node(old_name, 0);
615 if (unlink(newpath) < 0) {
616 if (errno == EPERM) {
617 /* devfs, entry has already been renamed */
620 log_error("Unable to unlink device node for '%s'",
625 else if (dm_udev_get_sync_support() && check_udev)
626 log_warn("The node %s should have been renamed to %s "
627 "by udev but new node is not present. "
628 "Falling back to direct node rename.",
631 if (rename(oldpath, newpath) < 0) {
632 log_error("Unable to rename device node from '%s' to '%s'",
637 log_debug("Renamed %s to %s", oldpath, newpath);
643 static int _open_dev_node(const char *dev_name)
648 _build_dev_path(path, sizeof(path), dev_name);
650 if ((fd = open(path, O_RDONLY, 0)) < 0)
651 log_sys_error("open", path);
656 int get_dev_node_read_ahead(const char *dev_name, uint32_t *read_ahead)
660 long read_ahead_long;
663 log_error("Empty device name passed to BLKRAGET");
667 if ((fd = _open_dev_node(dev_name)) < 0)
670 if (ioctl(fd, BLKRAGET, &read_ahead_long)) {
671 log_sys_error("BLKRAGET", dev_name);
675 *read_ahead = (uint32_t) read_ahead_long;
676 log_debug("%s: read ahead is %" PRIu32, dev_name, *read_ahead);
685 static int _set_read_ahead(const char *dev_name, uint32_t read_ahead)
689 long read_ahead_long = (long) read_ahead;
692 log_error("Empty device name passed to BLKRAGET");
696 if ((fd = _open_dev_node(dev_name)) < 0)
699 log_debug("%s: Setting read ahead to %" PRIu32, dev_name, read_ahead);
701 if (ioctl(fd, BLKRASET, read_ahead_long)) {
702 log_sys_error("BLKRASET", dev_name);
712 static int _set_dev_node_read_ahead(const char *dev_name, uint32_t read_ahead,
713 uint32_t read_ahead_flags)
715 uint32_t current_read_ahead;
717 if (read_ahead == DM_READ_AHEAD_AUTO)
720 if (read_ahead == DM_READ_AHEAD_NONE)
723 if (read_ahead_flags & DM_READ_AHEAD_MINIMUM_FLAG) {
724 if (!get_dev_node_read_ahead(dev_name, ¤t_read_ahead))
727 if (current_read_ahead > read_ahead) {
728 log_debug("%s: retaining kernel read ahead of %" PRIu32
729 " (requested %" PRIu32 ")",
730 dev_name, current_read_ahead, read_ahead);
735 return _set_read_ahead(dev_name, read_ahead);
740 int get_dev_node_read_ahead(const char *dev_name, uint32_t *read_ahead)
747 static int _set_dev_node_read_ahead(const char *dev_name, uint32_t read_ahead,
748 uint32_t read_ahead_flags)
761 static int _do_node_op(node_op_t type, const char *dev_name, uint32_t major,
762 uint32_t minor, uid_t uid, gid_t gid, mode_t mode,
763 const char *old_name, uint32_t read_ahead,
764 uint32_t read_ahead_flags, int check_udev)
768 return _add_dev_node(dev_name, major, minor, uid, gid,
771 return _rm_dev_node(dev_name, check_udev);
773 return _rename_dev_node(old_name, dev_name, check_udev);
774 case NODE_READ_AHEAD:
775 return _set_dev_node_read_ahead(dev_name, read_ahead,
782 static DM_LIST_INIT(_node_ops);
784 struct node_op_parms {
794 uint32_t read_ahead_flags;
800 static void _store_str(char **pos, char **ptr, const char *str)
804 *pos += strlen(*ptr) + 1;
807 static int _stack_node_op(node_op_t type, const char *dev_name, uint32_t major,
808 uint32_t minor, uid_t uid, gid_t gid, mode_t mode,
809 const char *old_name, uint32_t read_ahead,
810 uint32_t read_ahead_flags, int check_udev)
812 struct node_op_parms *nop;
813 struct dm_list *noph, *nopht;
814 size_t len = strlen(dev_name) + strlen(old_name) + 2;
818 * Ignore any outstanding operations on the node if deleting it
820 if (type == NODE_DEL) {
821 dm_list_iterate_safe(noph, nopht, &_node_ops) {
822 nop = dm_list_item(noph, struct node_op_parms);
823 if (!strcmp(dev_name, nop->dev_name)) {
824 dm_list_del(&nop->list);
830 if (!(nop = dm_malloc(sizeof(*nop) + len))) {
831 log_error("Insufficient memory to stack mknod operation");
842 nop->read_ahead = read_ahead;
843 nop->read_ahead_flags = read_ahead_flags;
844 nop->check_udev = check_udev;
846 _store_str(&pos, &nop->dev_name, dev_name);
847 _store_str(&pos, &nop->old_name, old_name);
849 dm_list_add(&_node_ops, &nop->list);
854 static void _pop_node_ops(void)
856 struct dm_list *noph, *nopht;
857 struct node_op_parms *nop;
859 dm_list_iterate_safe(noph, nopht, &_node_ops) {
860 nop = dm_list_item(noph, struct node_op_parms);
861 _do_node_op(nop->type, nop->dev_name, nop->major, nop->minor,
862 nop->uid, nop->gid, nop->mode, nop->old_name,
863 nop->read_ahead, nop->read_ahead_flags,
865 dm_list_del(&nop->list);
870 int add_dev_node(const char *dev_name, uint32_t major, uint32_t minor,
871 uid_t uid, gid_t gid, mode_t mode, int check_udev)
873 log_debug("%s: Stacking NODE_ADD (%" PRIu32 ",%" PRIu32 ") %u:%u 0%o",
874 dev_name, major, minor, uid, gid, mode);
876 return _stack_node_op(NODE_ADD, dev_name, major, minor, uid,
877 gid, mode, "", 0, 0, check_udev);
880 int rename_dev_node(const char *old_name, const char *new_name, int check_udev)
882 log_debug("%s: Stacking NODE_RENAME to %s", old_name, new_name);
884 return _stack_node_op(NODE_RENAME, new_name, 0, 0, 0,
885 0, 0, old_name, 0, 0, check_udev);
888 int rm_dev_node(const char *dev_name, int check_udev)
890 log_debug("%s: Stacking NODE_DEL (replaces other stacked ops)", dev_name);
892 return _stack_node_op(NODE_DEL, dev_name, 0, 0, 0,
893 0, 0, "", 0, 0, check_udev);
896 int set_dev_node_read_ahead(const char *dev_name, uint32_t read_ahead,
897 uint32_t read_ahead_flags)
899 if (read_ahead == DM_READ_AHEAD_AUTO)
902 log_debug("%s: Stacking NODE_READ_AHEAD %" PRIu32 " (flags=%" PRIu32
903 ")", dev_name, read_ahead, read_ahead_flags);
905 return _stack_node_op(NODE_READ_AHEAD, dev_name, 0, 0, 0, 0,
906 0, "", read_ahead, read_ahead_flags, 0);
909 void update_devs(void)
914 int dm_set_dev_dir(const char *dev_dir)
918 if (*dev_dir != '/') {
919 log_debug("Invalid dev_dir value, %s: "
920 "not an absolute name.", dev_dir);
924 len = strlen(dev_dir);
925 slash = dev_dir[len-1] == '/' ? "" : "/";
927 if (snprintf(_dm_dir, sizeof _dm_dir, "%s%s%s", dev_dir, slash, DM_DIR)
929 log_debug("Invalid dev_dir value, %s: name too long.", dev_dir);
936 const char *dm_dir(void)
941 int dm_mknodes(const char *name)
946 if (!(dmt = dm_task_create(DM_DEVICE_MKNODES)))
949 if (name && !dm_task_set_name(dmt, name))
952 if (!dm_task_no_open_count(dmt))
955 r = dm_task_run(dmt);
958 dm_task_destroy(dmt);
962 int dm_driver_version(char *version, size_t size)
967 if (!(dmt = dm_task_create(DM_DEVICE_VERSION)))
970 if (!dm_task_run(dmt))
971 log_error("Failed to get driver version");
973 if (!dm_task_get_driver_version(dmt, version, size))
979 dm_task_destroy(dmt);
983 #ifndef UDEV_SYNC_SUPPORT
984 void dm_udev_set_sync_support(int sync_with_udev)
988 int dm_udev_get_sync_support(void)
993 int dm_task_set_cookie(struct dm_task *dmt, uint32_t *cookie, uint16_t flags)
995 if (dm_cookie_supported())
996 dmt->event_nr = flags << DM_UDEV_FLAGS_SHIFT;
1002 int dm_udev_complete(uint32_t cookie)
1007 int dm_udev_wait(uint32_t cookie)
1012 #else /* UDEV_SYNC_SUPPORT */
1015 static int _check_udev_is_running(void)
1018 # ifndef HAVE_UDEV_QUEUE_GET_UDEV_IS_ACTIVE
1020 log_debug("Could not get udev state because libudev library "
1021 "was not found and it was not compiled in. "
1022 "Assuming udev is not running.");
1025 # else /* HAVE_UDEV_QUEUE_GET_UDEV_IS_ACTIVE */
1028 struct udev_queue *udev_queue;
1031 if (!(udev = udev_new()))
1034 if (!(udev_queue = udev_queue_new(udev))) {
1039 if (!(r = udev_queue_get_udev_is_active(udev_queue)))
1040 log_debug("Udev is not running. "
1041 "Not using udev synchronisation code.");
1043 udev_queue_unref(udev_queue);
1049 log_error("Could not get udev state. Assuming udev is not running.");
1052 # endif /* HAVE_UDEV_QUEUE_GET_UDEV_IS_ACTIVE */
1056 void dm_udev_set_sync_support(int sync_with_udev)
1058 if (_udev_running < 0)
1059 _udev_running = _check_udev_is_running();
1061 _sync_with_udev = sync_with_udev;
1064 int dm_udev_get_sync_support(void)
1066 if (_udev_running < 0)
1067 _udev_running = _check_udev_is_running();
1069 return dm_cookie_supported() && _udev_running && _sync_with_udev;
1072 static int _get_cookie_sem(uint32_t cookie, int *semid)
1074 if (cookie >> 16 != DM_COOKIE_MAGIC) {
1075 log_error("Could not continue to access notification "
1076 "semaphore identified by cookie value %"
1077 PRIu32 " (0x%x). Incorrect cookie prefix.",
1082 if ((*semid = semget((key_t) cookie, 1, 0)) >= 0)
1087 log_error("Could not find notification "
1088 "semaphore identified by cookie "
1089 "value %" PRIu32 " (0x%x)",
1093 log_error("No permission to access "
1094 "notificaton semaphore identified "
1095 "by cookie value %" PRIu32 " (0x%x)",
1099 log_error("Failed to access notification "
1100 "semaphore identified by cookie "
1101 "value %" PRIu32 " (0x%x): %s",
1102 cookie, cookie, strerror(errno));
1109 static int _udev_notify_sem_inc(uint32_t cookie, int semid)
1111 struct sembuf sb = {0, 1, 0};
1113 if (semop(semid, &sb, 1) < 0) {
1114 log_error("semid %d: semop failed for cookie 0x%" PRIx32 ": %s",
1115 semid, cookie, strerror(errno));
1119 log_debug("Udev cookie 0x%" PRIx32 " (semid %d) incremented",
1125 static int _udev_notify_sem_dec(uint32_t cookie, int semid)
1127 struct sembuf sb = {0, -1, IPC_NOWAIT};
1129 if (semop(semid, &sb, 1) < 0) {
1132 log_error("semid %d: semop failed for cookie "
1134 "incorrect semaphore state",
1138 log_error("semid %d: semop failed for cookie "
1139 "0x%" PRIx32 ": %s",
1140 semid, cookie, strerror(errno));
1146 log_debug("Udev cookie 0x%" PRIx32 " (semid %d) decremented",
1152 static int _udev_notify_sem_destroy(uint32_t cookie, int semid)
1154 if (semctl(semid, 0, IPC_RMID, 0) < 0) {
1155 log_error("Could not cleanup notification semaphore "
1156 "identified by cookie value %" PRIu32 " (0x%x): %s",
1157 cookie, cookie, strerror(errno));
1161 log_debug("Udev cookie 0x%" PRIx32 " (semid %d) destroyed", cookie,
1167 static int _udev_notify_sem_create(uint32_t *cookie, int *semid)
1171 uint16_t base_cookie;
1172 uint32_t gen_cookie;
1174 if ((fd = open("/dev/urandom", O_RDONLY)) < 0) {
1175 log_error("Failed to open /dev/urandom "
1176 "to create random cookie value");
1181 /* Generate random cookie value. Be sure it is unique and non-zero. */
1183 /* FIXME Handle non-error returns from read(). Move _io() into libdm? */
1184 if (read(fd, &base_cookie, sizeof(base_cookie)) != sizeof(base_cookie)) {
1185 log_error("Failed to initialize notification cookie");
1189 gen_cookie = DM_COOKIE_MAGIC << 16 | base_cookie;
1191 if (base_cookie && (gen_semid = semget((key_t) gen_cookie,
1192 1, 0600 | IPC_CREAT | IPC_EXCL)) < 0) {
1195 /* if the semaphore key exists, we
1196 * simply generate another random one */
1200 log_error("Not enough memory to create "
1201 "notification semaphore");
1204 log_error("Limit for the maximum number "
1205 "of semaphores reached. You can "
1206 "check and set the limits in "
1207 "/proc/sys/kernel/sem.");
1210 log_error("Failed to create notification "
1211 "semaphore: %s", strerror(errno));
1215 } while (!base_cookie);
1217 log_debug("Udev cookie 0x%" PRIx32 " (semid %d) created",
1218 gen_cookie, gen_semid);
1220 if (semctl(gen_semid, 0, SETVAL, 1) < 0) {
1221 log_error("semid %d: semctl failed: %s", gen_semid, strerror(errno));
1222 /* We have to destroy just created semaphore
1223 * so it won't stay in the system. */
1224 (void) _udev_notify_sem_destroy(gen_cookie, gen_semid);
1228 log_debug("Udev cookie 0x%" PRIx32 " (semid %d) incremented",
1229 gen_cookie, gen_semid);
1235 *cookie = gen_cookie;
1248 int dm_task_set_cookie(struct dm_task *dmt, uint32_t *cookie, uint16_t flags)
1252 if (dm_cookie_supported())
1253 dmt->event_nr = flags << DM_UDEV_FLAGS_SHIFT;
1255 if (!dm_udev_get_sync_support()) {
1261 if (!_get_cookie_sem(*cookie, &semid))
1263 } else if (!_udev_notify_sem_create(cookie, &semid))
1266 if (!_udev_notify_sem_inc(*cookie, semid)) {
1267 log_error("Could not set notification semaphore "
1268 "identified by cookie value %" PRIu32 " (0x%x)",
1273 dmt->event_nr |= ~DM_UDEV_FLAGS_MASK & *cookie;
1274 dmt->cookie_set = 1;
1276 log_debug("Udev cookie 0x%" PRIx32 " (semid %d) assigned to dm_task "
1277 "with flags 0x%" PRIx16, *cookie, semid, flags);
1286 int dm_udev_complete(uint32_t cookie)
1290 if (!cookie || !dm_udev_get_sync_support())
1293 if (!_get_cookie_sem(cookie, &semid))
1296 if (!_udev_notify_sem_dec(cookie, semid)) {
1297 log_error("Could not signal waiting process using notification "
1298 "semaphore identified by cookie value %" PRIu32 " (0x%x)",
1306 int dm_udev_wait(uint32_t cookie)
1309 struct sembuf sb = {0, 0, 0};
1311 if (!cookie || !dm_udev_get_sync_support())
1314 if (!_get_cookie_sem(cookie, &semid))
1317 if (!_udev_notify_sem_dec(cookie, semid)) {
1318 log_error("Failed to set a proper state for notification "
1319 "semaphore identified by cookie value %" PRIu32 " (0x%x) "
1320 "to initialize waiting for incoming notifications.",
1322 (void) _udev_notify_sem_destroy(cookie, semid);
1326 log_debug("Udev cookie 0x%" PRIx32 " (semid %d): Waiting for zero",
1330 if (semop(semid, &sb, 1) < 0) {
1333 else if (errno == EIDRM)
1336 log_error("Could not set wait state for notification semaphore "
1337 "identified by cookie value %" PRIu32 " (0x%x): %s",
1338 cookie, cookie, strerror(errno));
1339 (void) _udev_notify_sem_destroy(cookie, semid);
1343 return _udev_notify_sem_destroy(cookie, semid);
1346 #endif /* UDEV_SYNC_SUPPORT */