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                 if (scan->prune.nelms == 0 &&
 185                     (scan->prune.head.flags & HAMMER_IOC_PRUNE_ALL) == 0) {
 186                         fprintf(stderr, "No snapshots found\n");
 187                         continue;
 188                 }
 189
 190                 printf("Prune %s: objspace %016jx:%04x %016jx:%04x "
 191                        "pfs_id %d\n",
 192                        scan->filesystem,
 193                        (uintmax_t)scan->prune.key_beg.obj_id,
 194                        scan->prune.key_beg.localization,
 195                        (uintmax_t)scan->prune.key_end.obj_id,
 196                        scan->prune.key_end.localization,
 197                        pfs.pfs_id);
 198                 printf("Prune %s: prune_min is %dd/%02d:%02d:%02d\n",
 199                        scan->filesystem,
 200                         pfs.ondisk->prune_min / (24 * 60 * 60),
 201                         pfs.ondisk->prune_min / 60 / 60 % 24,
 202                         pfs.ondisk->prune_min / 60 % 60,
 203                         pfs.ondisk->prune_min % 60);
 204
 205                 RunningIoctl = 1;
 206                 if (ioctl(fd, HAMMERIOC_PRUNE, &scan->prune) < 0) {
 207                         printf("Prune %s failed: %s\n",
 208                                scan->filesystem, strerror(errno));
 209                         rcode = 2;
 210                 } else if (scan->prune.head.flags & HAMMER_IOC_HEAD_INTR) {
 211                         printf("Prune %s interrupted by timer at "
 212                                "%016jx %04x\n",
 213                                scan->filesystem,
 214                                (uintmax_t)scan->prune.key_cur.obj_id,
 215                                scan->prune.key_cur.localization);
 216                         if (CyclePath)
 217                                 hammer_set_cycle(&scan->prune.key_cur, 0);
 218                         rcode = 0;
 219                 } else {
 220                         if (CyclePath)
 221                                 hammer_reset_cycle();
 222                         printf("Prune %s succeeded\n", scan->filesystem);
 223                 }
 224                 printf("Pruned %jd/%jd records (%jd directory entries) "
 225                        "and %jd bytes\n",
 226                         (uintmax_t)scan->prune.stat_rawrecords,
 227                         (uintmax_t)scan->prune.stat_scanrecords,
 228                         (uintmax_t)scan->prune.stat_dirrecords,
 229                         (uintmax_t)scan->prune.stat_bytes
 230                 );
 231                 RunningIoctl = 0;
 232                 close(fd);
 233         }
 234         if (rcode)
 235                 exit(rcode);
 236 }
 237
 238 /*
 239  * Scan a directory for softlinks representing snapshots and build
 240  * associated softprune structures.
 241  *
 242  * NOTE: Once a filesystem is completely converted to the meta-data
 243  *       snapshot mechanic we don't have to scan softlinks any more
 244  *       and can just use the meta-data.  But for now we do both.
 245  */
 246 static void
 247 hammer_softprune_scandir(struct softprune **basep,
 248                          struct hammer_ioc_prune *template,
 249                          const char *dirname)
 250 {
 251         struct stat st;
 252         struct dirent *den;
 253         DIR *dir;
 254         char *path;
 255         int len;
 256         char *linkbuf;
 257         char *ptr;
 258
 259         path = NULL;
 260         linkbuf = malloc(MAXPATHLEN);
 261
 262         if ((dir = opendir(dirname)) == NULL)
 263                 err(1, "Cannot open directory %s", dirname);
 264         while ((den = readdir(dir)) != NULL) {
 265                 if (strcmp(den->d_name, ".") == 0)
 266                         continue;
 267                 if (strcmp(den->d_name, "..") == 0)
 268                         continue;
 269                 if (path)
 270                         free(path);
 271                 asprintf(&path, "%s/%s", dirname, den->d_name);
 272                 if (lstat(path, &st) < 0)
 273                         continue;
 274                 if (!S_ISLNK(st.st_mode))
 275                         continue;
 276                 if ((len = readlink(path, linkbuf, MAXPATHLEN - 1)) < 0)
 277                         continue;
 278                 linkbuf[len] = 0;
 279                 if ((ptr = strrchr(linkbuf, '@')) &&
 280                     ptr > linkbuf && ptr[-1] == '@')
 281                         hammer_softprune_addentry(basep, template,
 282                                                   dirname, den->d_name, &st,
 283                                                   linkbuf, ptr - 1);
 284         }
 285         free(linkbuf);
 286         if (path)
 287                 free(path);
 288 }
 289
 290 /*
 291  * Scan a directory for softlinks representing snapshots.
 292  * Return 1 if the directory contains snapshots, otherwise 0.
 293  */
 294 int
 295 hammer_softprune_testdir(const char *dirname)
 296 {
 297         struct softprune *base = NULL;
 298         struct hammer_ioc_prune dummy_template;
 299
 300         bzero(&dummy_template, sizeof(dummy_template));
 301         hammer_softprune_scandir(&base, &dummy_template, dirname);
 302
 303         if (base)
 304                 return(1);
 305         return(0);
 306 }
 307
 308 /*
 309  * Scan the metadata snapshots for the filesystem and either delete them
 310  * or add them to the pruning list.
 311  */
 312 static
 313 int
 314 hammer_softprune_scanmeta(int fd, struct softprune *scan, int delete_all)
 315 {
 316         struct hammer_ioc_version       version;
 317         struct hammer_ioc_snapshot      snapshot;
 318         struct hammer_ioc_snapshot      dsnapshot;
 319         hammer_snapshot_data_t          snap;
 320         time_t ct;
 321
 322         /*
 323          * Stop if we can't get the version.  Meta-data snapshots only
 324          * exist for HAMMER version 3 or greater.
 325          */
 326         bzero(&version, sizeof(version));
 327         if (ioctl(fd, HAMMERIOC_GET_VERSION, &version) < 0)
 328                 return(-1);
 329         HammerVersion = version.cur_version;
 330         if (version.cur_version < 3)
 331                 return(0);
 332
 333         bzero(&snapshot, sizeof(snapshot));
 334         bzero(&dsnapshot, sizeof(dsnapshot));
 335
 336         /*
 337          * Scan meta-data snapshots, either add them to the prune list or
 338          * delete them.  When deleting, just skip any entries which cannot
 339          * be deleted.
 340          */
 341         for (;;) {
 342                 if (ioctl(fd, HAMMERIOC_GET_SNAPSHOT, &snapshot) < 0) {
 343                         printf("hammer prune: Unable to access "
 344                                "meta-data snaps: %s\n", strerror(errno));
 345                         return(-1);
 346                 }
 347                 while (snapshot.index < snapshot.count) {
 348                         snap = &snapshot.snaps[snapshot.index];
 349                         if (delete_all) {
 350                                 dsnapshot.snaps[dsnapshot.count++] = *snap;
 351                                 if (dsnapshot.count == HAMMER_SNAPS_PER_IOCTL)
 352                                         hammer_meta_flushdelete(fd, &dsnapshot);
 353                         } else {
 354                                 ct = snap->ts / 1000000ULL;
 355                                 hammer_softprune_addelm(scan, snap->tid,
 356                                                         ct, ct);
 357                         }
 358                         ++snapshot.index;
 359                 }
 360                 if (snapshot.head.flags & HAMMER_IOC_SNAPSHOT_EOF)
 361                         break;
 362                 snapshot.index = 0;
 363         }
 364         if (delete_all)
 365                 hammer_meta_flushdelete(fd, &dsnapshot);
 366         return(0);
 367 }
 368
 369 /*
 370  * Flush any entries built up in the deletion snapshot ioctl structure.
 371  * Used during a prune-everything.
 372  */
 373 static void
 374 hammer_meta_flushdelete(int fd, struct hammer_ioc_snapshot *dsnap)
 375 {
 376         while (dsnap->index < dsnap->count) {
 377                 if (ioctl(fd, HAMMERIOC_DEL_SNAPSHOT, dsnap) < 0)
 378                         break;
 379                 if (dsnap->head.error == 0)
 380                         break;
 381                 ++dsnap->index;
 382         }
 383         dsnap->index = 0;
 384         dsnap->count = 0;
 385 }
 386
 387 /*
 388  * Add the softlink to the appropriate softprune structure, creating a new
 389  * one if necessary.
 390  */
 391 static
 392 struct softprune *
 393 hammer_softprune_addentry(struct softprune **basep,
 394                          struct hammer_ioc_prune *template,
 395                          const char *dirpath, const char *denname __unused,
 396                          struct stat *st,
 397                          const char *linkbuf, const char *tidptr)
 398 {
 399         struct softprune *scan;
 400         struct statfs fs;
 401         char *fspath;
 402
 403         /*
 404          * Calculate filesystem path.
 405          */
 406         if (linkbuf[0] == '/')
 407                 asprintf(&fspath, "%*.*s",
 408                          (int)(tidptr - linkbuf), (int)(tidptr - linkbuf),
 409                          linkbuf);
 410         else
 411                 asprintf(&fspath, "%s/%*.*s", dirpath,
 412                          (int)(tidptr - linkbuf), (int)(tidptr - linkbuf),
 413                          linkbuf);
 414         if (statfs(fspath, &fs) < 0) {
 415                 free(fspath);
 416                 return(NULL);
 417         }
 418
 419         /*
 420          * Locate the filesystem in an existing softprune structure
 421          */
 422         for (scan = *basep; scan; scan = scan->next) {
 423                 if (bcmp(&fs.f_fsid, &scan->fs.f_fsid, sizeof(fs.f_fsid)) != 0)
 424                         continue;
 425                 if (strcmp(fs.f_mntonname, scan->fs.f_mntonname) != 0)
 426                         continue;
 427                 break;
 428         }
 429
 430         /*
 431          * Create a new softprune structure if necessasry
 432          */
 433         if (scan == NULL) {
 434                 scan = malloc(sizeof(*scan));
 435                 bzero(scan, sizeof(*scan));
 436
 437                 scan->fs = fs;
 438                 scan->filesystem = fspath;
 439                 scan->prune = *template;
 440                 scan->maxelms = 32;
 441                 scan->prune.elms = malloc(sizeof(struct hammer_ioc_prune_elm) *
 442                                           scan->maxelms);
 443                 scan->next = *basep;
 444                 *basep = scan;
 445         } else {
 446                 free(fspath);
 447         }
 448         hammer_softprune_addelm(scan,
 449                                 (hammer_tid_t)strtoull(tidptr + 2, NULL, 0),
 450                                 (st ? st->st_ctime : 0),
 451                                 (st ? st->st_mtime : 0));
 452         return(scan);
 453 }
 454
 455 /*
 456  * Add the entry (unsorted).  Just set the beg_tid, we will sort
 457  * and set the remaining entries later.
 458  *
 459  * Always leave one entry free for our terminator.
 460  */
 461 static void
 462 hammer_softprune_addelm(struct softprune *scan, hammer_tid_t tid,
 463                         time_t ct, time_t mt)
 464 {
 465         struct hammer_ioc_prune_elm *elm;
 466
 467         if (scan->prune.nelms >= scan->maxelms - 1) {
 468                 scan->maxelms = (scan->maxelms * 3 / 2);
 469                 scan->prune.elms = realloc(scan->prune.elms,
 470                                            sizeof(*elm) * scan->maxelms);
 471         }
 472
 473         /*
 474          * NOTE: Temporarily store the snapshot timestamp in mod_tid.
 475          *       This will be cleaned up in the finalization phase.
 476          */
 477         elm = &scan->prune.elms[scan->prune.nelms];
 478         elm->beg_tid = tid;
 479         elm->end_tid = 0;
 480         elm->mod_tid = 0;
 481         if (ct < mt)
 482                 elm->mod_tid = ct;
 483         else
 484                 elm->mod_tid = mt;
 485         ++scan->prune.nelms;
 486 }
 487
 488 /*
 489  * Finalize a softprune structure after scanning in its softlinks.
 490  * Sort the elements, remove duplicates, and then fill in end_tid and
 491  * mod_tid.
 492  *
 493  * The array must end up in descending order.
 494  */
 495 static int
 496 hammer_softprune_qsort_cmp(const void *arg1, const void *arg2)
 497 {
 498         const struct hammer_ioc_prune_elm *elm1 = arg1;
 499         const struct hammer_ioc_prune_elm *elm2 = arg2;
 500
 501         if (elm1->beg_tid < elm2->beg_tid)
 502                 return(1);
 503         if (elm1->beg_tid > elm2->beg_tid)
 504                 return(-1);
 505         return(0);
 506 }
 507
 508 static void
 509 hammer_softprune_finalize(struct softprune *scan)
 510 {
 511         struct hammer_ioc_prune_elm *elm;
 512         time_t t;
 513         long delta;
 514         int i;
 515
 516         /*
 517          * Don't do anything if there are no elements.
 518          */
 519         if (scan->prune.nelms == 0)
 520                 return;
 521
 522         /*
 523          * Sort the elements in descending order, remove duplicates, and
 524          * fill in any missing bits.
 525          */
 526         qsort(scan->prune.elms, scan->prune.nelms, sizeof(*elm),
 527               hammer_softprune_qsort_cmp);
 528
 529         for (i = 0; i < scan->prune.nelms; ++i) {
 530                 elm = &scan->prune.elms[i];
 531                 if (i == 0) {
 532                         /*
 533                          * First (highest TID) (also last if only one element)
 534                          */
 535                         elm->end_tid = HAMMER_MAX_TID;
 536                 } else if (elm[0].beg_tid == elm[-1].beg_tid) {
 537                         /*
 538                          * Remove duplicate
 539                          */
 540                         --scan->prune.nelms;
 541                         if (i != scan->prune.nelms)
 542                                 bcopy(elm + 1, elm,
 543                                       (scan->prune.nelms - i) * sizeof(*elm));
 544                         --i;
 545                         continue;
 546                 } else {
 547                         /*
 548                          * Middle or last.
 549                          */
 550                         elm->end_tid = elm[-1].beg_tid;
 551                 }
 552         }
 553
 554         /*
 555          * If a minimum retention time (in seconds) is configured for the
 556          * PFS, remove any snapshots from the pruning list that are within
 557          * the period.
 558          */
 559         if (scan->prune_min) {
 560                 t = time(NULL);
 561                 for (i = scan->prune.nelms - 1; i >= 0; --i) {
 562                         elm = &scan->prune.elms[i];
 563                         if (elm->mod_tid == 0)
 564                                 continue;
 565                         delta = (long)(t - (time_t)elm->mod_tid);
 566                         if (delta < scan->prune_min)
 567                                 break;
 568                 }
 569                 ++i;
 570                 if (i) {
 571                         printf("Prune %s: prune_min: Will not clean between "
 572                                "the teeth of the first %d snapshots\n",
 573                                scan->filesystem, i);
 574                         bcopy(&scan->prune.elms[i], &scan->prune.elms[0],
 575                               (scan->prune.nelms - i) * sizeof(scan->prune.elms[0]));
 576                         scan->prune.elms[0].end_tid = HAMMER_MAX_TID;
 577                         scan->prune.nelms -= i;
 578                 }
 579         }
 580
 581         /*
 582          * Remove the first entry.  This entry represents the prune from
 583          * the most recent snapshot to current.  We wish to retain the
 584          * fine-grained history for this region.
 585          */
 586         if (scan->prune.nelms) {
 587                 bcopy(&scan->prune.elms[1], &scan->prune.elms[0],
 588                       (scan->prune.nelms - 1) * sizeof(scan->prune.elms[0]));
 589                 --scan->prune.nelms;
 590         }
 591
 592         /*
 593          * Add a final element to prune everything from transaction id
 594          * 0 to the lowest transaction id (aka last so far).
 595          */
 596         if (scan->prune.nelms) {
 597                 assert(scan->prune.nelms < scan->maxelms);
 598                 elm = &scan->prune.elms[scan->prune.nelms];
 599                 elm->beg_tid = 1;
 600                 elm->end_tid = elm[-1].beg_tid;
 601                 ++scan->prune.nelms;
 602         }
 603
 604         /*
 605          * Adjust mod_tid to what the ioctl() expects.
 606          */
 607         for (i = 0; i < scan->prune.nelms; ++i) {
 608                 elm = &scan->prune.elms[i];
 609                 elm->mod_tid = elm->end_tid - elm->beg_tid;
 610                 printf("TID %016jx - %016jx\n",
 611                        (uintmax_t)elm->beg_tid, (uintmax_t)elm->end_tid);
 612         }
 613 }
 614
 615 static
 616 void
 617 softprune_usage(int code)
 618 {
 619         fprintf(stderr, "Badly formed prune command, use:\n");
 620         fprintf(stderr, "hammer prune <softlink-dir>\n");
 621         fprintf(stderr, "hammer prune-everything <filesystem>\n");
 622         exit(code);
 623 }
 624