sbin/hammer/cmd_softprune.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sbin/hammer/cmd_softprune.c,v 1.7 2008/08/21 23:28:43 thomas Exp $
  35  */
  36
  37 #include "hammer.h"
  38
  39 struct softprune {
  40         struct softprune *next;
  41         struct statfs fs;
  42         char *filesystem;
  43         struct hammer_ioc_prune prune;
  44         int maxelms;
  45         int prune_min;
  46 };
  47
  48 static void hammer_softprune_scandir(struct softprune **basep,
  49                         struct hammer_ioc_prune *template,
  50                         const char *dirname);
  51 static int hammer_softprune_scanmeta(int fd, struct softprune *scan,
  52                         int delete_all);
  53 static void hammer_meta_flushdelete(int fd, struct hammer_ioc_snapshot *dsnap);
  54 static struct softprune *hammer_softprune_addentry(struct softprune **basep,
  55                         struct hammer_ioc_prune *template,
  56                         const char *dirpath, const char *denname,
  57                         struct stat *st,
  58                         const char *linkbuf, const char *tidptr);
  59 static void hammer_softprune_addelm(struct softprune *scan, hammer_tid_t tid,
  60                         time_t ct, time_t mt);
  61 static void hammer_softprune_finalize(struct softprune *scan);
  62 static void softprune_usage(int code);
  63
  64 /*
  65  * prune <softlink-dir>
  66  * prune-everything <filesystem>
  67  */
  68 void
  69 hammer_cmd_softprune(char **av, int ac, int everything_opt)
  70 {
  71         struct hammer_ioc_prune template;
  72         struct hammer_ioc_pseudofs_rw pfs;
  73         struct softprune *base, *scan;
  74         int fd;
  75         int rcode;
  76
  77         base = NULL;
  78         rcode = 0;
  79         if (TimeoutOpt > 0)
  80                 alarm(TimeoutOpt);
  81
  82         clrpfs(&pfs, NULL, -1);
  83
  84         /*
  85          * NOTE: To restrict to a single file XXX we have to set
  86          * the localization the same (not yet implemented).  Typically
  87          * two passes would be needed, one using HAMMER_LOCALIZE_MISC
  88          * and one using HAMMER_LOCALIZE_INODE.
  89          */
  90
  91         bzero(&template, sizeof(template));
  92         template.key_beg.localization = HAMMER_MIN_LOCALIZATION;
  93         template.key_beg.obj_id = HAMMER_MIN_OBJID;
  94         template.key_end.localization = HAMMER_MAX_LOCALIZATION;
  95         template.key_end.obj_id = HAMMER_MAX_OBJID;
  96         hammer_get_cycle(&template.key_end, NULL);
  97         template.stat_oldest_tid = HAMMER_MAX_TID;
  98
  99         /*
 100          * For now just allow one directory
 101          */
 102         if (ac == 0 || ac > 1)
 103                 softprune_usage(1);
 104
 105         /*
 106          * Scan the softlink directory.
 107          */
 108         if (everything_opt) {
 109                 const char *dummylink = "";
 110                 scan = hammer_softprune_addentry(&base, &template,
 111                                                  *av, NULL, NULL,
 112                                                  dummylink, dummylink);
 113                 if (scan == NULL)
 114                         softprune_usage(1);
 115                 scan->prune.nelms = 0;
 116                 scan->prune.head.flags |= HAMMER_IOC_PRUNE_ALL;
 117         } else {
 118                 hammer_softprune_scandir(&base, &template, *av);
 119                 if (base == NULL) {
 120                         const char *dummylink = "";
 121                         scan = hammer_softprune_addentry(&base, &template,
 122                                                          *av, NULL, NULL,
 123                                                          dummylink, dummylink);
 124                         if (scan == NULL)
 125                                 softprune_usage(1);
 126                         scan->prune.nelms = 0;
 127                 }
 128                 ++av;
 129                 --ac;
 130         }
 131
 132         /*
 133          * XXX future (need to store separate cycles for each filesystem)
 134          */
 135         if (base->next)
 136                 errx(1, "Currently only one HAMMER filesystem may "
 137                         "be specified in the softlink scan");
 138
 139         /*
 140          * Issue the prunes
 141          */
 142         for (scan = base; scan; scan = scan->next) {
 143                 /*
 144                  * Open the filesystem for ioctl calls and extract the
 145                  * PFS.
 146                  */
 147                 fd = open(scan->filesystem, O_RDONLY);
 148                 if (fd < 0) {
 149                         warn("Unable to open %s", scan->filesystem);
 150                         rcode = 1;
 151                         continue;
 152                 }
 153
 154                 if (ioctl(fd, HAMMERIOC_GET_PSEUDOFS, &pfs) < 0) {
 155                         warn("Filesystem %s is not HAMMER", scan->filesystem);
 156                         rcode = 1;
 157                         close(fd);
 158                         continue;
 159                 }
 160                 scan->prune_min = pfs.ondisk->prune_min;
 161
 162                 /*
 163                  * Incorporate meta-data snapshots into the pruning regimen.
 164                  * If pruning everything we delete the meta-data snapshots.
 165                  */
 166                 if (hammer_softprune_scanmeta(fd, scan, everything_opt) < 0) {
 167                         warn("Filesystem %s could not scan meta-data snaps",
 168                              scan->filesystem);
 169                         rcode = 1;
 170                         close(fd);
 171                         continue;
 172                 }
 173
 174                 /*
 175                  * Finalize operations
 176                  */
 177                 hammer_softprune_finalize(scan);
 178                 if (everything_opt) {
 179                         printf("Prune %s: EVERYTHING\n",
 180                                scan->filesystem);
 181                 } else {
 182                         printf("Prune %s: %d snapshots\n",
 183                                scan->filesystem, scan->prune.nelms);
 184                 }
 185                 if (scan->prune.nelms == 0 &&
 186                     (scan->prune.head.flags & HAMMER_IOC_PRUNE_ALL) == 0) {
 187                         fprintf(stderr, "No snapshots found\n");
 188                         continue;
 189                 }
 190
 191                 printf("Prune %s: objspace %016jx:%04x %016jx:%04x "
 192                        "pfs_id %d\n",
 193                        scan->filesystem,
 194                        (uintmax_t)scan->prune.key_beg.obj_id,
 195                        scan->prune.key_beg.localization,
 196                        (uintmax_t)scan->prune.key_end.obj_id,
 197                        scan->prune.key_end.localization,
 198                        pfs.pfs_id);
 199                 printf("Prune %s: prune_min is %dd/%02d:%02d:%02d\n",
 200                        scan->filesystem,
 201                         pfs.ondisk->prune_min / (24 * 60 * 60),
 202                         pfs.ondisk->prune_min / 60 / 60 % 24,
 203                         pfs.ondisk->prune_min / 60 % 60,
 204                         pfs.ondisk->prune_min % 60);
 205
 206                 RunningIoctl = 1;
 207                 if (ioctl(fd, HAMMERIOC_PRUNE, &scan->prune) < 0) {
 208                         printf("Prune %s failed: %s\n",
 209                                scan->filesystem, strerror(errno));
 210                         rcode = 2;
 211                 } else if (scan->prune.head.flags & HAMMER_IOC_HEAD_INTR) {
 212                         printf("Prune %s interrupted by timer at "
 213                                "%016jx %04x\n",
 214                                scan->filesystem,
 215                                (uintmax_t)scan->prune.key_cur.obj_id,
 216                                scan->prune.key_cur.localization);
 217                         if (CyclePath)
 218                                 hammer_set_cycle(&scan->prune.key_cur, 0);
 219                         rcode = 0;
 220                 } else {
 221                         if (CyclePath)
 222                                 hammer_reset_cycle();
 223                         printf("Prune %s succeeded\n", scan->filesystem);
 224                 }
 225                 printf("Pruned %jd/%jd records (%jd directory entries) "
 226                        "and %jd bytes\n",
 227                         (uintmax_t)scan->prune.stat_rawrecords,
 228                         (uintmax_t)scan->prune.stat_scanrecords,
 229                         (uintmax_t)scan->prune.stat_dirrecords,
 230                         (uintmax_t)scan->prune.stat_bytes
 231                 );
 232                 RunningIoctl = 0;
 233                 close(fd);
 234         }
 235         if (rcode)
 236                 exit(rcode);
 237 }
 238
 239 /*
 240  * Scan a directory for softlinks representing snapshots and build
 241  * associated softprune structures.
 242  *
 243  * NOTE: Once a filesystem is completely converted to the meta-data
 244  *       snapshot mechanic we don't have to scan softlinks any more
 245  *       and can just use the meta-data.  But for now we do both.
 246  */
 247 static void
 248 hammer_softprune_scandir(struct softprune **basep,
 249                          struct hammer_ioc_prune *template,
 250                          const char *dirname)
 251 {
 252         struct stat st;
 253         struct dirent *den;
 254         DIR *dir;
 255         char *path;
 256         int len;
 257         char *linkbuf;
 258         char *ptr;
 259
 260         path = NULL;
 261         linkbuf = malloc(MAXPATHLEN);
 262
 263         if ((dir = opendir(dirname)) == NULL)
 264                 err(1, "Cannot open directory %s", dirname);
 265         while ((den = readdir(dir)) != NULL) {
 266                 if (strcmp(den->d_name, ".") == 0)
 267                         continue;
 268                 if (strcmp(den->d_name, "..") == 0)
 269                         continue;
 270                 if (path)
 271                         free(path);
 272                 asprintf(&path, "%s/%s", dirname, den->d_name);
 273                 if (lstat(path, &st) < 0)
 274                         continue;
 275                 if (!S_ISLNK(st.st_mode))
 276                         continue;
 277                 if ((len = readlink(path, linkbuf, MAXPATHLEN - 1)) < 0)
 278                         continue;
 279                 linkbuf[len] = 0;
 280                 if ((ptr = strrchr(linkbuf, '@')) &&
 281                     ptr > linkbuf && ptr[-1] == '@') {
 282                         hammer_softprune_addentry(basep, template,
 283                                                   dirname, den->d_name, &st,
 284                                                   linkbuf, ptr - 1);
 285                 }
 286         }
 287         free(linkbuf);
 288         if (path)
 289                 free(path);
 290 }
 291
 292 /*
 293  * Scan a directory for softlinks representing snapshots.
 294  * Return 1 if the directory contains snapshots, otherwise 0.
 295  */
 296 int
 297 hammer_softprune_testdir(const char *dirname)
 298 {
 299         struct softprune *base = NULL;
 300         struct hammer_ioc_prune dummy_template;
 301
 302         bzero(&dummy_template, sizeof(dummy_template));
 303         hammer_softprune_scandir(&base, &dummy_template, dirname);
 304
 305         if (base)
 306                 return(1);
 307         return(0);
 308 }
 309
 310 /*
 311  * Scan the metadata snapshots for the filesystem and either delete them
 312  * or add them to the pruning list.
 313  */
 314 static
 315 int
 316 hammer_softprune_scanmeta(int fd, struct softprune *scan, int delete_all)
 317 {
 318         struct hammer_ioc_version       version;
 319         struct hammer_ioc_snapshot      snapshot;
 320         struct hammer_ioc_snapshot      dsnapshot;
 321         hammer_snapshot_data_t          snap;
 322         time_t ct;
 323
 324         /*
 325          * Stop if we can't get the version.  Meta-data snapshots only
 326          * exist for HAMMER version 3 or greater.
 327          */
 328         bzero(&version, sizeof(version));
 329         if (ioctl(fd, HAMMERIOC_GET_VERSION, &version) < 0)
 330                 return(-1);
 331         HammerVersion = version.cur_version;
 332         if (version.cur_version < 3)
 333                 return(0);
 334
 335         bzero(&snapshot, sizeof(snapshot));
 336         bzero(&dsnapshot, sizeof(dsnapshot));
 337
 338         /*
 339          * Scan meta-data snapshots, either add them to the prune list or
 340          * delete them.  When deleting, just skip any entries which cannot
 341          * be deleted.
 342          */
 343         for (;;) {
 344                 if (ioctl(fd, HAMMERIOC_GET_SNAPSHOT, &snapshot) < 0) {
 345                         printf("hammer prune: Unable to access "
 346                                "meta-data snaps: %s\n", strerror(errno));
 347                         return(-1);
 348                 }
 349                 while (snapshot.index < snapshot.count) {
 350                         snap = &snapshot.snaps[snapshot.index];
 351                         if (delete_all) {
 352                                 dsnapshot.snaps[dsnapshot.count++] = *snap;
 353                                 if (dsnapshot.count == HAMMER_SNAPS_PER_IOCTL)
 354                                         hammer_meta_flushdelete(fd, &dsnapshot);
 355                         } else {
 356                                 ct = snap->ts / 1000000ULL;
 357                                 hammer_softprune_addelm(scan, snap->tid,
 358                                                         ct, ct);
 359                         }
 360                         ++snapshot.index;
 361                 }
 362                 if (snapshot.head.flags & HAMMER_IOC_SNAPSHOT_EOF)
 363                         break;
 364                 snapshot.index = 0;
 365         }
 366         if (delete_all)
 367                 hammer_meta_flushdelete(fd, &dsnapshot);
 368         return(0);
 369 }
 370
 371 /*
 372  * Flush any entries built up in the deletion snapshot ioctl structure.
 373  * Used during a prune-everything.
 374  */
 375 static void
 376 hammer_meta_flushdelete(int fd, struct hammer_ioc_snapshot *dsnap)
 377 {
 378         while (dsnap->index < dsnap->count) {
 379                 if (ioctl(fd, HAMMERIOC_DEL_SNAPSHOT, dsnap) < 0)
 380                         break;
 381                 if (dsnap->head.error == 0)
 382                         break;
 383                 ++dsnap->index;
 384         }
 385         dsnap->index = 0;
 386         dsnap->count = 0;
 387 }
 388
 389 /*
 390  * Add the softlink to the appropriate softprune structure, creating a new
 391  * one if necessary.
 392  */
 393 static
 394 struct softprune *
 395 hammer_softprune_addentry(struct softprune **basep,
 396                          struct hammer_ioc_prune *template,
 397                          const char *dirpath, const char *denname __unused,
 398                          struct stat *st,
 399                          const char *linkbuf, const char *tidptr)
 400 {
 401         struct softprune *scan;
 402         struct statfs fs;
 403         char *fspath;
 404
 405         /*
 406          * Calculate filesystem path.
 407          */
 408         if (linkbuf[0] == '/') {
 409                 asprintf(&fspath, "%*.*s",
 410                          (int)(tidptr - linkbuf), (int)(tidptr - linkbuf),
 411                          linkbuf);
 412         } else {
 413                 asprintf(&fspath, "%s/%*.*s", dirpath,
 414                          (int)(tidptr - linkbuf), (int)(tidptr - linkbuf),
 415                          linkbuf);
 416         }
 417         if (statfs(fspath, &fs) < 0) {
 418                 free(fspath);
 419                 return(NULL);
 420         }
 421
 422         /*
 423          * Locate the filesystem in an existing softprune structure
 424          */
 425         for (scan = *basep; scan; scan = scan->next) {
 426                 if (bcmp(&fs.f_fsid, &scan->fs.f_fsid, sizeof(fs.f_fsid)) != 0)
 427                         continue;
 428                 if (strcmp(fs.f_mntonname, scan->fs.f_mntonname) != 0)
 429                         continue;
 430                 break;
 431         }
 432
 433         /*
 434          * Create a new softprune structure if necessasry
 435          */
 436         if (scan == NULL) {
 437                 scan = malloc(sizeof(*scan));
 438                 bzero(scan, sizeof(*scan));
 439
 440                 scan->fs = fs;
 441                 scan->filesystem = fspath;
 442                 scan->prune = *template;
 443                 scan->maxelms = 32;
 444                 scan->prune.elms = malloc(sizeof(struct hammer_ioc_prune_elm) *
 445                                           scan->maxelms);
 446                 scan->next = *basep;
 447                 *basep = scan;
 448         } else {
 449                 free(fspath);
 450         }
 451         hammer_softprune_addelm(scan,
 452                                 (hammer_tid_t)strtoull(tidptr + 2, NULL, 0),
 453                                 (st ? st->st_ctime : 0),
 454                                 (st ? st->st_mtime : 0));
 455         return(scan);
 456 }
 457
 458 /*
 459  * Add the entry (unsorted).  Just set the beg_tid, we will sort
 460  * and set the remaining entries later.
 461  *
 462  * Always leave one entry free for our terminator.
 463  */
 464 static void
 465 hammer_softprune_addelm(struct softprune *scan, hammer_tid_t tid,
 466                         time_t ct, time_t mt)
 467 {
 468         struct hammer_ioc_prune_elm *elm;
 469
 470         if (scan->prune.nelms >= scan->maxelms - 1) {
 471                 scan->maxelms = (scan->maxelms * 3 / 2);
 472                 scan->prune.elms = realloc(scan->prune.elms,
 473                                            sizeof(*elm) * scan->maxelms);
 474         }
 475
 476         /*
 477          * NOTE: Temporarily store the snapshot timestamp in mod_tid.
 478          *       This will be cleaned up in the finalization phase.
 479          */
 480         elm = &scan->prune.elms[scan->prune.nelms];
 481         elm->beg_tid = tid;
 482         elm->end_tid = 0;
 483         elm->mod_tid = 0;
 484         if (ct < mt)
 485                 elm->mod_tid = ct;
 486         else
 487                 elm->mod_tid = mt;
 488         ++scan->prune.nelms;
 489 }
 490
 491 /*
 492  * Finalize a softprune structure after scanning in its softlinks.
 493  * Sort the elements, remove duplicates, and then fill in end_tid and
 494  * mod_tid.
 495  *
 496  * The array must end up in descending order.
 497  */
 498 static int
 499 hammer_softprune_qsort_cmp(const void *arg1, const void *arg2)
 500 {
 501         const struct hammer_ioc_prune_elm *elm1 = arg1;
 502         const struct hammer_ioc_prune_elm *elm2 = arg2;
 503
 504         if (elm1->beg_tid < elm2->beg_tid)
 505                 return(1);
 506         if (elm1->beg_tid > elm2->beg_tid)
 507                 return(-1);
 508         return(0);
 509 }
 510
 511 static void
 512 hammer_softprune_finalize(struct softprune *scan)
 513 {
 514         struct hammer_ioc_prune_elm *elm;
 515         time_t t;
 516         long delta;
 517         int i;
 518
 519         /*
 520          * Don't do anything if there are no elements.
 521          */
 522         if (scan->prune.nelms == 0)
 523                 return;
 524
 525         /*
 526          * Sort the elements in descending order, remove duplicates, and
 527          * fill in any missing bits.
 528          */
 529         qsort(scan->prune.elms, scan->prune.nelms, sizeof(*elm),
 530               hammer_softprune_qsort_cmp);
 531
 532         for (i = 0; i < scan->prune.nelms; ++i) {
 533                 elm = &scan->prune.elms[i];
 534                 if (i == 0) {
 535                         /*
 536                          * First (highest TID) (also last if only one element)
 537                          */
 538                         elm->end_tid = HAMMER_MAX_TID;
 539                 } else if (elm[0].beg_tid == elm[-1].beg_tid) {
 540                         /*
 541                          * Remove duplicate
 542                          */
 543                         --scan->prune.nelms;
 544                         if (i != scan->prune.nelms) {
 545                                 bcopy(elm + 1, elm,
 546                                       (scan->prune.nelms - i) * sizeof(*elm));
 547                         }
 548                         --i;
 549                         continue;
 550                 } else {
 551                         /*
 552                          * Middle or last.
 553                          */
 554                         elm->end_tid = elm[-1].beg_tid;
 555                 }
 556         }
 557
 558         /*
 559          * If a minimum retention time (in seconds) is configured for the
 560          * PFS, remove any snapshots from the pruning list that are within
 561          * the period.
 562          */
 563         if (scan->prune_min) {
 564                 t = time(NULL);
 565                 for (i = scan->prune.nelms - 1; i >= 0; --i) {
 566                         elm = &scan->prune.elms[i];
 567                         if (elm->mod_tid == 0)
 568                                 continue;
 569                         delta = (long)(t - (time_t)elm->mod_tid);
 570                         if (delta < scan->prune_min)
 571                                 break;
 572                 }
 573                 ++i;
 574                 if (i) {
 575                         printf("Prune %s: prune_min: Will not clean between "
 576                                "the teeth of the first %d snapshots\n",
 577                                scan->filesystem, i);
 578                         bcopy(&scan->prune.elms[i], &scan->prune.elms[0],
 579                               (scan->prune.nelms - i) * sizeof(scan->prune.elms[0]));
 580                         scan->prune.elms[0].end_tid = HAMMER_MAX_TID;
 581                         scan->prune.nelms -= i;
 582                 }
 583         }
 584
 585         /*
 586          * Remove the first entry.  This entry represents the prune from
 587          * the most recent snapshot to current.  We wish to retain the
 588          * fine-grained history for this region.
 589          */
 590         if (scan->prune.nelms) {
 591                 bcopy(&scan->prune.elms[1], &scan->prune.elms[0],
 592                       (scan->prune.nelms - 1) * sizeof(scan->prune.elms[0]));
 593                 --scan->prune.nelms;
 594         }
 595
 596         /*
 597          * Add a final element to prune everything from transaction id
 598          * 0 to the lowest transaction id (aka last so far).
 599          */
 600         if (scan->prune.nelms) {
 601                 assert(scan->prune.nelms < scan->maxelms);
 602                 elm = &scan->prune.elms[scan->prune.nelms];
 603                 elm->beg_tid = 1;
 604                 elm->end_tid = elm[-1].beg_tid;
 605                 ++scan->prune.nelms;
 606         }
 607
 608         /*
 609          * Adjust mod_tid to what the ioctl() expects.
 610          */
 611         for (i = 0; i < scan->prune.nelms; ++i) {
 612                 elm = &scan->prune.elms[i];
 613                 elm->mod_tid = elm->end_tid - elm->beg_tid;
 614                 printf("TID %016jx - %016jx\n",
 615                        (uintmax_t)elm->beg_tid, (uintmax_t)elm->end_tid);
 616         }
 617 }
 618
 619 static
 620 void
 621 softprune_usage(int code)
 622 {
 623         fprintf(stderr, "Badly formed prune command, use:\n");
 624         fprintf(stderr, "hammer prune <softlink-dir>\n");
 625         fprintf(stderr, "hammer prune-everything <filesystem>\n");
 626         exit(code);
 627 }
 628