contrib/lvm2/dist/lib/activate/fs.c

   1 /*      $NetBSD: fs.c,v 1.4 2009/12/02 00:58:03 haad Exp $      */
   2
   3 /*
   4  * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
   5  * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
   6  *
   7  * This file is part of LVM2.
   8  *
   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.
  12  *
  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
  16  */
  17
  18 #include "lib.h"
  19 #include "fs.h"
  20 #include "toolcontext.h"
  21 #include "lvm-string.h"
  22 #include "lvm-file.h"
  23 #include "memlock.h"
  24
  25 #include <sys/stat.h>
  26 #include <fcntl.h>
  27 #include <unistd.h>
  28 #include <limits.h>
  29 #include <dirent.h>
  30
  31 static int _mk_dir(const char *dev_dir, const char *vg_name)
  32 {
  33         char vg_path[PATH_MAX];
  34         mode_t old_umask;
  35
  36         if (dm_snprintf(vg_path, sizeof(vg_path), "%s%s",
  37                          dev_dir, vg_name) == -1) {
  38                 log_error("Couldn't construct name of volume "
  39                           "group directory.");
  40                 return 0;
  41         }
  42
  43         if (dir_exists(vg_path))
  44                 return 1;
  45
  46         log_very_verbose("Creating directory %s", vg_path);
  47
  48         old_umask = umask(DM_DEV_DIR_UMASK);
  49         if (mkdir(vg_path, 0777)) {
  50                 log_sys_error("mkdir", vg_path);
  51                 umask(old_umask);
  52                 return 0;
  53         }
  54         umask(old_umask);
  55
  56         return 1;
  57 }
  58
  59 static int _rm_dir(const char *dev_dir, const char *vg_name)
  60 {
  61         char vg_path[PATH_MAX];
  62
  63         if (dm_snprintf(vg_path, sizeof(vg_path), "%s%s",
  64                          dev_dir, vg_name) == -1) {
  65                 log_error("Couldn't construct name of volume "
  66                           "group directory.");
  67                 return 0;
  68         }
  69
  70         if (dir_exists(vg_path) && is_empty_dir(vg_path)) {
  71                 log_very_verbose("Removing directory %s", vg_path);
  72                 rmdir(vg_path);
  73         }
  74
  75         return 1;
  76 }
  77
  78 static void _rm_blks(const char *dir)
  79 {
  80         const char *name;
  81         char path[PATH_MAX];
  82         struct dirent *dirent;
  83         struct stat buf;
  84         DIR *d;
  85
  86         if (!(d = opendir(dir))) {
  87                 log_sys_error("opendir", dir);
  88                 return;
  89         }
  90
  91         while ((dirent = readdir(d))) {
  92                 name = dirent->d_name;
  93
  94                 if (!strcmp(name, ".") || !strcmp(name, ".."))
  95                         continue;
  96
  97                 if (dm_snprintf(path, sizeof(path), "%s/%s", dir, name) == -1) {
  98                         log_error("Couldn't create path for %s", name);
  99                         continue;
 100                 }
 101
 102                 if (!lstat(path, &buf)) {
 103                         if (!S_ISBLK(buf.st_mode))
 104                                 continue;
 105                         log_very_verbose("Removing %s", path);
 106                         if (unlink(path) < 0)
 107                                 log_sys_error("unlink", path);
 108                 }
 109 #ifdef __NetBSD__
 110                 if (dm_snprintf(path, sizeof(path), "%s/r%s", dir, name) == -1) {
 111                         log_error("Couldn't create path for r%s", name);
 112                         continue;
 113                 }
 114
 115                 if (!lstat(path, &buf)) {
 116                         if (!S_ISCHR(buf.st_mode))
 117                                 continue;
 118                         log_very_verbose("Removing %s", path);
 119                         if (unlink(path) < 0)
 120                                 log_sys_error("unlink", path);
 121                 }
 122 #endif
 123         }
 124 }
 125
 126 static int _mk_link(const char *dev_dir, const char *vg_name,
 127                     const char *lv_name, const char *dev)
 128 {
 129         char lv_path[PATH_MAX], link_path[PATH_MAX], lvm1_group_path[PATH_MAX];
 130         char vg_path[PATH_MAX];
 131         struct stat buf, buf_lp;
 132
 133 #ifdef __NetBSD__
 134         /* Add support for creating links to BSD raw devices */
 135         char raw_lv_path[PATH_MAX], raw_link_path[PATH_MAX];
 136 #endif
 137
 138         if (dm_snprintf(vg_path, sizeof(vg_path), "%s%s",
 139                          dev_dir, vg_name) == -1) {
 140                 log_error("Couldn't create path for volume group dir %s",
 141                           vg_name);
 142                 return 0;
 143         }
 144
 145 #ifdef __NetBSD__
 146         if (dm_snprintf(raw_lv_path, sizeof(raw_lv_path), "%s/r%s", vg_path,
 147                 lv_name) == -1) {
 148                 log_error("Couldn't create source pathname for "
 149                     "logical volume link r%s", lv_name);
 150                 return 0;
 151         }
 152
 153         if (dm_snprintf(raw_link_path, sizeof(raw_link_path), "%s/r%s",
 154                 dm_dir(), dev) == -1) {
 155                 log_error("Couldn't create destination pathname for "
 156                     "logical volume link for %s", lv_name);
 157                 return 0;
 158         }
 159
 160         if (!lstat(raw_lv_path, &buf)) {
 161                 if (!S_ISLNK(buf.st_mode) && !S_ISCHR(buf.st_mode)) {
 162                         log_error("Symbolic link %s not created: file exists",
 163                                   raw_link_path);
 164                         return 0;
 165                 }
 166
 167                 log_very_verbose("Removing %s", raw_lv_path);
 168                 if (unlink(raw_lv_path) < 0) {
 169                         log_sys_error("unlink", raw_lv_path);
 170                         return 0;
 171                 }
 172         }
 173
 174         log_very_verbose("Linking %s -> %s", raw_lv_path, raw_link_path);
 175         if (symlink(raw_link_path, raw_lv_path) < 0) {
 176                 log_sys_error("symlink", raw_lv_path);
 177                 return 0;
 178         }
 179
 180 #endif
 181         if (dm_snprintf(lv_path, sizeof(lv_path), "%s/%s", vg_path,
 182                          lv_name) == -1) {
 183                 log_error("Couldn't create source pathname for "
 184                           "logical volume link %s", lv_name);
 185                 return 0;
 186         }
 187
 188         if (dm_snprintf(link_path, sizeof(link_path), "%s/%s",
 189                          dm_dir(), dev) == -1) {
 190                 log_error("Couldn't create destination pathname for "
 191                           "logical volume link for %s", lv_name);
 192                 return 0;
 193         }
 194
 195         if (dm_snprintf(lvm1_group_path, sizeof(lvm1_group_path), "%s/group",
 196                          vg_path) == -1) {
 197                 log_error("Couldn't create pathname for LVM1 group file for %s",
 198                           vg_name);
 199                 return 0;
 200         }
 201
 202         /* To reach this point, the VG must have been locked.
 203          * As locking fails if the VG is active under LVM1, it's
 204          * now safe to remove any LVM1 devices we find here
 205          * (as well as any existing LVM2 symlink). */
 206         if (!lstat(lvm1_group_path, &buf)) {
 207                 if (!S_ISCHR(buf.st_mode)) {
 208                         log_error("Non-LVM1 character device found at %s",
 209                                   lvm1_group_path);
 210                 } else {
 211                         _rm_blks(vg_path);
 212
 213                         log_very_verbose("Removing %s", lvm1_group_path);
 214                         if (unlink(lvm1_group_path) < 0)
 215                                 log_sys_error("unlink", lvm1_group_path);
 216                 }
 217         }
 218
 219         if (!lstat(lv_path, &buf)) {
 220                 if (!S_ISLNK(buf.st_mode) && !S_ISBLK(buf.st_mode)) {
 221                         log_error("Symbolic link %s not created: file exists",
 222                                   link_path);
 223                         return 0;
 224                 }
 225
 226                 if (dm_udev_get_sync_support()) {
 227                         /* Check udev created the correct link. */
 228                         if (!stat(link_path, &buf_lp) &&
 229                             !stat(lv_path, &buf)) {
 230                                 if (buf_lp.st_rdev == buf.st_rdev)
 231                                         return 1;
 232                                 else
 233                                         log_warn("Symlink %s that should have been "
 234                                                  "created by udev does not have "
 235                                                  "correct target. Falling back to "
 236                                                  "direct link creation", lv_path);
 237                         } else
 238                                 log_warn("Symlink %s that should have been "
 239                                          "created by udev could not be checked "
 240                                          "for its correctness. Falling back to "
 241                                          "direct link creation.", lv_path);
 242
 243                 }
 244
 245                 log_very_verbose("Removing %s", lv_path);
 246                 if (unlink(lv_path) < 0) {
 247                         log_sys_error("unlink", lv_path);
 248                         return 0;
 249                 }
 250         } else if (dm_udev_get_sync_support())
 251                 log_warn("The link %s should had been created by udev "
 252                           "but it was not found. Falling back to "
 253                           "direct link creation.", lv_path);
 254
 255         log_very_verbose("Linking %s -> %s", lv_path, link_path);
 256         if (symlink(link_path, lv_path) < 0) {
 257                 log_sys_error("symlink", lv_path);
 258                 return 0;
 259         }
 260
 261         if (!dm_set_selinux_context(lv_path, S_IFLNK))
 262                 return_0;
 263
 264         return 1;
 265 }
 266
 267 static int _rm_link(const char *dev_dir, const char *vg_name,
 268                     const char *lv_name)
 269 {
 270         struct stat buf;
 271         char lv_path[PATH_MAX];
 272
 273 #ifdef __NetBSD__
 274         /* Add support for removing links to BSD raw devices */
 275         char raw_lv_path[PATH_MAX];
 276
 277         if (dm_snprintf(raw_lv_path, sizeof(raw_lv_path), "%s%s/r%s",
 278                          dev_dir, vg_name, lv_name) == -1) {
 279                 log_error("Couldn't determine link pathname.");
 280                 return 0;
 281         }
 282
 283         if (lstat(raw_lv_path, &buf) || !S_ISLNK(buf.st_mode)) {
 284                 if (errno == ENOENT)
 285                         return 1;
 286                 log_error("%s not symbolic link - not removing", raw_lv_path);
 287                 return 0;
 288         }
 289
 290         log_very_verbose("Removing link %s", raw_lv_path);
 291         if (unlink(raw_lv_path) < 0) {
 292                 log_sys_error("unlink", raw_lv_path);
 293                 return 0;
 294         }
 295 #endif
 296         if (dm_snprintf(lv_path, sizeof(lv_path), "%s%s/%s",
 297                          dev_dir, vg_name, lv_name) == -1) {
 298                 log_error("Couldn't determine link pathname.");
 299                 return 0;
 300         }
 301
 302         if (lstat(lv_path, &buf) && errno == ENOENT)
 303                 return 1;
 304         else if (dm_udev_get_sync_support())
 305                 log_warn("The link %s should have been removed by udev "
 306                          "but it is still present. Falling back to "
 307                          "direct link removal.", lv_path);
 308
 309         if (!S_ISLNK(buf.st_mode)) {
 310                 log_error("%s not symbolic link - not removing", lv_path);
 311                 return 0;
 312         }
 313
 314         log_very_verbose("Removing link %s", lv_path);
 315         if (unlink(lv_path) < 0) {
 316                 log_sys_error("unlink", lv_path);
 317                 return 0;
 318         }
 319
 320         return 1;
 321 }
 322
 323 typedef enum {
 324         FS_ADD,
 325         FS_DEL,
 326         FS_RENAME
 327 } fs_op_t;
 328
 329 static int _do_fs_op(fs_op_t type, const char *dev_dir, const char *vg_name,
 330                      const char *lv_name, const char *dev,
 331                      const char *old_lv_name)
 332 {
 333         switch (type) {
 334         case FS_ADD:
 335                 if (!_mk_dir(dev_dir, vg_name) ||
 336                     !_mk_link(dev_dir, vg_name, lv_name, dev))
 337                         return_0;
 338                 break;
 339         case FS_DEL:
 340                 if (!_rm_link(dev_dir, vg_name, lv_name) ||
 341                     !_rm_dir(dev_dir, vg_name))
 342                         return_0;
 343                 break;
 344                 /* FIXME Use rename() */
 345         case FS_RENAME:
 346                 if (old_lv_name && !_rm_link(dev_dir, vg_name, old_lv_name))
 347                         stack;
 348
 349                 if (!_mk_link(dev_dir, vg_name, lv_name, dev))
 350                         stack;
 351         }
 352
 353         return 1;
 354 }
 355
 356 static DM_LIST_INIT(_fs_ops);
 357
 358 struct fs_op_parms {
 359         struct dm_list list;
 360         fs_op_t type;
 361         char *dev_dir;
 362         char *vg_name;
 363         char *lv_name;
 364         char *dev;
 365         char *old_lv_name;
 366         char names[0];
 367 };
 368
 369 static void _store_str(char **pos, char **ptr, const char *str)
 370 {
 371         strcpy(*pos, str);
 372         *ptr = *pos;
 373         *pos += strlen(*ptr) + 1;
 374 }
 375
 376 static int _stack_fs_op(fs_op_t type, const char *dev_dir, const char *vg_name,
 377                         const char *lv_name, const char *dev,
 378                         const char *old_lv_name)
 379 {
 380         struct fs_op_parms *fsp;
 381         size_t len = strlen(dev_dir) + strlen(vg_name) + strlen(lv_name) +
 382             strlen(dev) + strlen(old_lv_name) + 5;
 383         char *pos;
 384
 385         if (!(fsp = dm_malloc(sizeof(*fsp) + len))) {
 386                 log_error("No space to stack fs operation");
 387                 return 0;
 388         }
 389
 390         pos = fsp->names;
 391         fsp->type = type;
 392
 393         _store_str(&pos, &fsp->dev_dir, dev_dir);
 394         _store_str(&pos, &fsp->vg_name, vg_name);
 395         _store_str(&pos, &fsp->lv_name, lv_name);
 396         _store_str(&pos, &fsp->dev, dev);
 397         _store_str(&pos, &fsp->old_lv_name, old_lv_name);
 398
 399         dm_list_add(&_fs_ops, &fsp->list);
 400
 401         return 1;
 402 }
 403
 404 static void _pop_fs_ops(void)
 405 {
 406         struct dm_list *fsph, *fspht;
 407         struct fs_op_parms *fsp;
 408
 409         dm_list_iterate_safe(fsph, fspht, &_fs_ops) {
 410                 fsp = dm_list_item(fsph, struct fs_op_parms);
 411                 _do_fs_op(fsp->type, fsp->dev_dir, fsp->vg_name, fsp->lv_name,
 412                           fsp->dev, fsp->old_lv_name);
 413                 dm_list_del(&fsp->list);
 414                 dm_free(fsp);
 415         }
 416 }
 417
 418 static int _fs_op(fs_op_t type, const char *dev_dir, const char *vg_name,
 419                   const char *lv_name, const char *dev, const char *old_lv_name)
 420 {
 421         if (memlock()) {
 422                 if (!_stack_fs_op(type, dev_dir, vg_name, lv_name, dev,
 423                                   old_lv_name))
 424                         return_0;
 425                 return 1;
 426         }
 427
 428         return _do_fs_op(type, dev_dir, vg_name, lv_name, dev, old_lv_name);
 429 }
 430
 431 int fs_add_lv(const struct logical_volume *lv, const char *dev)
 432 {
 433         return _fs_op(FS_ADD, lv->vg->cmd->dev_dir, lv->vg->name, lv->name,
 434                       dev, "");
 435 }
 436
 437 int fs_del_lv(const struct logical_volume *lv)
 438 {
 439         return _fs_op(FS_DEL, lv->vg->cmd->dev_dir, lv->vg->name, lv->name,
 440                       "", "");
 441 }
 442
 443 int fs_del_lv_byname(const char *dev_dir, const char *vg_name, const char *lv_name)
 444 {
 445         return _fs_op(FS_DEL, dev_dir, vg_name, lv_name, "", "");
 446 }
 447
 448 int fs_rename_lv(struct logical_volume *lv, const char *dev,
 449                 const char *old_vgname, const char *old_lvname)
 450 {
 451         if (strcmp(old_vgname, lv->vg->name)) {
 452                 return
 453                         (_fs_op(FS_DEL, lv->vg->cmd->dev_dir, old_vgname, old_lvname, "", "") &&
 454                          _fs_op(FS_ADD, lv->vg->cmd->dev_dir, lv->vg->name, lv->name, dev, ""));
 455         }
 456         else
 457                 return _fs_op(FS_RENAME, lv->vg->cmd->dev_dir, lv->vg->name, lv->name,
 458                               dev, old_lvname);
 459 }
 460
 461 void fs_unlock(void)
 462 {
 463         if (!memlock()) {
 464                 dm_lib_release();
 465                 _pop_fs_ops();
 466         }
 467 }