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                 /* not reached */
 105         }
 106
 107         /*
 108          * Scan the softlink directory.
 109          */
 110         if (everything_opt) {
 111                 const char *dummylink = "";
 112                 scan = hammer_softprune_addentry(&base, &template,
 113                                                  *av, NULL, NULL,
 114                                                  dummylink, dummylink);
 115                 if (scan == NULL) {
 116                         softprune_usage(1);
 117                         /* not reached */
 118                 }
 119                 scan->prune.nelms = 0;
 120                 scan->prune.head.flags |= HAMMER_IOC_PRUNE_ALL;
 121         } else {
 122                 hammer_softprune_scandir(&base, &template, *av);
 123                 if (base == NULL) {
 124                         const char *dummylink = "";
 125                         scan = hammer_softprune_addentry(&base, &template,
 126                                                          *av, NULL, NULL,
 127                                                          dummylink, dummylink);
 128                         if (scan == NULL) {
 129                                 softprune_usage(1);
 130                                 /* not reached */
 131                         }
 132                         scan->prune.nelms = 0;
 133                 }
 134                 ++av;
 135                 --ac;
 136         }
 137
 138         /*
 139          * XXX future (need to store separate cycles for each filesystem)
 140          */
 141         if (base->next) {
 142                 errx(1, "Currently only one HAMMER filesystem may "
 143                         "be specified in the softlink scan");
 144                 /* not reached */
 145         }
 146
 147         /*
 148          * Issue the prunes
 149          */
 150         for (scan = base; scan; scan = scan->next) {
 151                 /*
 152                  * Open the filesystem for ioctl calls and extract the
 153                  * PFS.
 154                  */
 155                 fd = open(scan->filesystem, O_RDONLY);
 156                 if (fd < 0) {
 157                         warn("Unable to open %s", scan->filesystem);
 158                         rcode = 1;
 159                         continue;
 160                 }
 161
 162                 if (ioctl(fd, HAMMERIOC_GET_PSEUDOFS, &pfs) < 0) {
 163                         warn("Filesystem %s is not HAMMER", scan->filesystem);
 164                         rcode = 1;
 165                         close(fd);
 166                         continue;
 167                 }
 168                 scan->prune_min = pfs.ondisk->prune_min;
 169
 170                 /*
 171                  * Incorporate meta-data snapshots into the pruning regimen.
 172                  * If pruning everything we delete the meta-data snapshots.
 173                  */
 174                 if (hammer_softprune_scanmeta(fd, scan, everything_opt) < 0) {
 175                         warn("Filesystem %s could not scan meta-data snaps",
 176                              scan->filesystem);
 177                         rcode = 1;
 178                         close(fd);
 179                         continue;
 180                 }
 181
 182                 /*
 183                  * Finalize operations
 184                  */
 185                 hammer_softprune_finalize(scan);
 186                 if (everything_opt) {
 187                         printf("Prune %s: EVERYTHING\n",
 188                                scan->filesystem);
 189                 } else {
 190                         printf("Prune %s: %d snapshots\n",
 191                                scan->filesystem, scan->prune.nelms);
 192                 }
 193                 if (scan->prune.nelms == 0 &&
 194                     (scan->prune.head.flags & HAMMER_IOC_PRUNE_ALL) == 0) {
 195                         fprintf(stderr, "No snapshots found\n");
 196                         continue;
 197                 }
 198
 199                 printf("Prune %s: objspace %016jx:%04x %016jx:%04x "
 200                        "pfs_id %d\n",
 201                        scan->filesystem,
 202                        (uintmax_t)scan->prune.key_beg.obj_id,
 203                        scan->prune.key_beg.localization,
 204                        (uintmax_t)scan->prune.key_end.obj_id,
 205                        scan->prune.key_end.localization,
 206                        pfs.pfs_id);
 207                 printf("Prune %s: prune_min is %dd/%02d:%02d:%02d\n",
 208                        scan->filesystem,
 209                         pfs.ondisk->prune_min / (24 * 60 * 60),
 210                         pfs.ondisk->prune_min / 60 / 60 % 24,
 211                         pfs.ondisk->prune_min / 60 % 60,
 212                         pfs.ondisk->prune_min % 60);
 213
 214                 RunningIoctl = 1;
 215                 if (ioctl(fd, HAMMERIOC_PRUNE, &scan->prune) < 0) {
 216                         printf("Prune %s failed: %s\n",
 217                                scan->filesystem, strerror(errno));
 218                         rcode = 2;
 219                 } else if (scan->prune.head.flags & HAMMER_IOC_HEAD_INTR) {
 220                         printf("Prune %s interrupted by timer at "
 221                                "%016jx %04x\n",
 222                                scan->filesystem,
 223                                (uintmax_t)scan->prune.key_cur.obj_id,
 224                                scan->prune.key_cur.localization);
 225                         if (CyclePath)
 226                                 hammer_set_cycle(&scan->prune.key_cur, 0);
 227                         rcode = 0;
 228                 } else {
 229                         if (CyclePath)
 230                                 hammer_reset_cycle();
 231                         printf("Prune %s succeeded\n", scan->filesystem);
 232                 }
 233                 printf("Pruned %jd/%jd records (%jd directory entries) "
 234                        "and %jd bytes\n",
 235                         (uintmax_t)scan->prune.stat_rawrecords,
 236                         (uintmax_t)scan->prune.stat_scanrecords,
 237                         (uintmax_t)scan->prune.stat_dirrecords,
 238                         (uintmax_t)scan->prune.stat_bytes
 239                 );
 240                 RunningIoctl = 0;
 241                 close(fd);
 242         }
 243         if (rcode)
 244                 exit(rcode);
 245 }
 246
 247 /*
 248  * Scan a directory for softlinks representing snapshots and build
 249  * associated softprune structures.
 250  *
 251  * NOTE: Once a filesystem is completely converted to the meta-data
 252  *       snapshot mechanic we don't have to scan softlinks any more
 253  *       and can just use the meta-data.  But for now we do both.
 254  */
 255 static
 256 void
 257 hammer_softprune_scandir(struct softprune **basep,
 258                          struct hammer_ioc_prune *template,
 259                          const char *dirname)
 260 {
 261         struct stat st;
 262         struct dirent *den;
 263         DIR *dir;
 264         char *path;
 265         int len;
 266         char *linkbuf;
 267         char *ptr;
 268
 269         path = NULL;
 270         linkbuf = malloc(MAXPATHLEN);
 271
 272         if ((dir = opendir(dirname)) == NULL) {
 273                 err(1, "Cannot open directory %s", dirname);
 274                 /* not reached */
 275         }
 276         while ((den = readdir(dir)) != NULL) {
 277                 if (strcmp(den->d_name, ".") == 0)
 278                         continue;
 279                 if (strcmp(den->d_name, "..") == 0)
 280                         continue;
 281                 if (path)
 282                         free(path);
 283                 asprintf(&path, "%s/%s", dirname, den->d_name);
 284                 if (lstat(path, &st) < 0)
 285                         continue;
 286                 if (!S_ISLNK(st.st_mode))
 287                         continue;
 288                 if ((len = readlink(path, linkbuf, MAXPATHLEN - 1)) < 0)
 289                         continue;
 290                 linkbuf[len] = 0;
 291                 if ((ptr = strrchr(linkbuf, '@')) &&
 292                     ptr > linkbuf && ptr[-1] == '@') {
 293                         hammer_softprune_addentry(basep, template,
 294                                                   dirname, den->d_name, &st,
 295                                                   linkbuf, ptr - 1);
 296                 }
 297         }
 298         free(linkbuf);
 299         if (path)
 300                 free(path);
 301 }
 302
 303 /*
 304  * Scan a directory for softlinks representing snapshots.
 305  * Return 1 if the directory contains snapshots, otherwise 0.
 306  */
 307 int
 308 hammer_softprune_testdir(const char *dirname)
 309 {
 310         struct softprune *base = NULL;
 311         struct hammer_ioc_prune dummy_template;
 312
 313         bzero(&dummy_template, sizeof(dummy_template));
 314         hammer_softprune_scandir(&base, &dummy_template, dirname);
 315
 316         if (base)
 317                 return(1);
 318         return(0);
 319 }
 320
 321 /*
 322  * Scan the metadata snapshots for the filesystem and either delete them
 323  * or add them to the pruning list.
 324  */
 325 static
 326 int
 327 hammer_softprune_scanmeta(int fd, struct softprune *scan, int delete_all)
 328 {
 329         struct hammer_ioc_version       version;
 330         struct hammer_ioc_snapshot      snapshot;
 331         struct hammer_ioc_snapshot      dsnapshot;
 332         hammer_snapshot_data_t          snap;
 333         time_t ct;
 334
 335         /*
 336          * Stop if we can't get the version.  Meta-data snapshots only
 337          * exist for HAMMER version 3 or greater.
 338          */
 339         bzero(&version, sizeof(version));
 340         if (ioctl(fd, HAMMERIOC_GET_VERSION, &version) < 0)
 341                 return(-1);
 342         HammerVersion = version.cur_version;
 343         if (version.cur_version < 3)
 344                 return(0);
 345
 346         bzero(&snapshot, sizeof(snapshot));
 347         bzero(&dsnapshot, sizeof(dsnapshot));
 348
 349         /*
 350          * Scan meta-data snapshots, either add them to the prune list or
 351          * delete them.  When deleting, just skip any entries which cannot
 352          * be deleted.
 353          */
 354         for (;;) {
 355                 if (ioctl(fd, HAMMERIOC_GET_SNAPSHOT, &snapshot) < 0) {
 356                         printf("hammer prune: Unable to access "
 357                                "meta-data snaps: %s\n", strerror(errno));
 358                         return(-1);
 359                 }
 360                 while (snapshot.index < snapshot.count) {
 361                         snap = &snapshot.snaps[snapshot.index];
 362                         if (delete_all) {
 363                                 dsnapshot.snaps[dsnapshot.count++] = *snap;
 364                                 if (dsnapshot.count == HAMMER_SNAPS_PER_IOCTL)
 365                                         hammer_meta_flushdelete(fd, &dsnapshot);
 366                         } else {
 367                                 ct = snap->ts / 1000000ULL;
 368                                 hammer_softprune_addelm(scan, snap->tid,
 369                                                         ct, ct);
 370                         }
 371                         ++snapshot.index;
 372                 }
 373                 if (snapshot.head.flags & HAMMER_IOC_SNAPSHOT_EOF)
 374                         break;
 375                 snapshot.index = 0;
 376         }
 377         if (delete_all)
 378                 hammer_meta_flushdelete(fd, &dsnapshot);
 379         return(0);
 380 }
 381
 382 /*
 383  * Flush any entries built up in the deletion snapshot ioctl structure.
 384  * Used during a prune-everything.
 385  */
 386 static
 387 void
 388 hammer_meta_flushdelete(int fd, struct hammer_ioc_snapshot *dsnap)
 389 {
 390         while (dsnap->index < dsnap->count) {
 391                 if (ioctl(fd, HAMMERIOC_DEL_SNAPSHOT, dsnap) < 0)
 392                         break;
 393                 if (dsnap->head.error == 0)
 394                         break;
 395                 ++dsnap->index;
 396         }
 397         dsnap->index = 0;
 398         dsnap->count = 0;
 399 }
 400
 401 /*
 402  * Add the softlink to the appropriate softprune structure, creating a new
 403  * one if necessary.
 404  */
 405 static
 406 struct softprune *
 407 hammer_softprune_addentry(struct softprune **basep,
 408                          struct hammer_ioc_prune *template,
 409                          const char *dirpath, const char *denname __unused,
 410                          struct stat *st,
 411                          const char *linkbuf, const char *tidptr)
 412 {
 413         struct softprune *scan;
 414         struct statfs fs;
 415         char *fspath;
 416
 417         /*
 418          * Calculate filesystem path.
 419          */
 420         if (linkbuf[0] == '/') {
 421                 asprintf(&fspath, "%*.*s",
 422                          (int)(tidptr - linkbuf), (int)(tidptr - linkbuf),
 423                          linkbuf);
 424         } else {
 425                 asprintf(&fspath, "%s/%*.*s", dirpath,
 426                          (int)(tidptr - linkbuf), (int)(tidptr - linkbuf),
 427                          linkbuf);
 428         }
 429         if (statfs(fspath, &fs) < 0) {
 430                 free(fspath);
 431                 return(NULL);
 432         }
 433
 434         /*
 435          * Locate the filesystem in an existing softprune structure
 436          */
 437         for (scan = *basep; scan; scan = scan->next) {
 438                 if (bcmp(&fs.f_fsid, &scan->fs.f_fsid, sizeof(fs.f_fsid)) != 0)
 439                         continue;
 440                 if (strcmp(fs.f_mntonname, scan->fs.f_mntonname) != 0)
 441                         continue;
 442                 break;
 443         }
 444
 445         /*
 446          * Create a new softprune structure if necessasry
 447          */
 448         if (scan == NULL) {
 449                 scan = malloc(sizeof(*scan));
 450                 bzero(scan, sizeof(*scan));
 451
 452                 scan->fs = fs;
 453                 scan->filesystem = fspath;
 454                 scan->prune = *template;
 455                 scan->maxelms = 32;
 456                 scan->prune.elms = malloc(sizeof(struct hammer_ioc_prune_elm) *
 457                                           scan->maxelms);
 458                 scan->next = *basep;
 459                 *basep = scan;
 460         } else {
 461                 free(fspath);
 462         }
 463         hammer_softprune_addelm(scan,
 464                                 (hammer_tid_t)strtoull(tidptr + 2, NULL, 0),
 465                                 (st ? st->st_ctime : 0),
 466                                 (st ? st->st_mtime : 0));
 467         return(scan);
 468 }
 469
 470 /*
 471  * Add the entry (unsorted).  Just set the beg_tid, we will sort
 472  * and set the remaining entries later.
 473  *
 474  * Always leave one entry free for our terminator.
 475  */
 476 static
 477 void
 478 hammer_softprune_addelm(struct softprune *scan, hammer_tid_t tid,
 479                         time_t ct, time_t mt)
 480 {
 481         struct hammer_ioc_prune_elm *elm;
 482
 483         if (scan->prune.nelms >= scan->maxelms - 1) {
 484                 scan->maxelms = (scan->maxelms * 3 / 2);
 485                 scan->prune.elms = realloc(scan->prune.elms,
 486                                            sizeof(*elm) * scan->maxelms);
 487         }
 488
 489         /*
 490          * NOTE: Temporarily store the snapshot timestamp in mod_tid.
 491          *       This will be cleaned up in the finalization phase.
 492          */
 493         elm = &scan->prune.elms[scan->prune.nelms];
 494         elm->beg_tid = tid;
 495         elm->end_tid = 0;
 496         elm->mod_tid = 0;
 497         if (ct < mt)
 498                 elm->mod_tid = ct;
 499         else
 500                 elm->mod_tid = mt;
 501         ++scan->prune.nelms;
 502 }
 503
 504 /*
 505  * Finalize a softprune structure after scanning in its softlinks.
 506  * Sort the elements, remove duplicates, and then fill in end_tid and
 507  * mod_tid.
 508  *
 509  * The array must end up in descending order.
 510  */
 511 static
 512 int
 513 hammer_softprune_qsort_cmp(const void *arg1, const void *arg2)
 514 {
 515         const struct hammer_ioc_prune_elm *elm1 = arg1;
 516         const struct hammer_ioc_prune_elm *elm2 = arg2;
 517
 518         if (elm1->beg_tid < elm2->beg_tid)
 519                 return(1);
 520         if (elm1->beg_tid > elm2->beg_tid)
 521                 return(-1);
 522         return(0);
 523 }
 524
 525 static
 526 void
 527 hammer_softprune_finalize(struct softprune *scan)
 528 {
 529         struct hammer_ioc_prune_elm *elm;
 530         time_t t;
 531         long delta;
 532         int i;
 533
 534         /*
 535          * Don't do anything if there are no elements.
 536          */
 537         if (scan->prune.nelms == 0)
 538                 return;
 539
 540         /*
 541          * Sort the elements in descending order, remove duplicates, and
 542          * fill in any missing bits.
 543          */
 544         qsort(scan->prune.elms, scan->prune.nelms, sizeof(*elm),
 545               hammer_softprune_qsort_cmp);
 546
 547         for (i = 0; i < scan->prune.nelms; ++i) {
 548                 elm = &scan->prune.elms[i];
 549                 if (i == 0) {
 550                         /*
 551                          * First (highest TID) (also last if only one element)
 552                          */
 553                         elm->end_tid = HAMMER_MAX_TID;
 554                 } else if (elm[0].beg_tid == elm[-1].beg_tid) {
 555                         /*
 556                          * Remove duplicate
 557                          */
 558                         --scan->prune.nelms;
 559                         if (i != scan->prune.nelms) {
 560                                 bcopy(elm + 1, elm,
 561                                       (scan->prune.nelms - i) * sizeof(*elm));
 562                         }
 563                         --i;
 564                         continue;
 565                 } else {
 566                         /*
 567                          * Middle or last.
 568                          */
 569                         elm->end_tid = elm[-1].beg_tid;
 570                 }
 571         }
 572
 573         /*
 574          * If a minimum retention time (in seconds) is configured for the
 575          * PFS, remove any snapshots from the pruning list that are within
 576          * the period.
 577          */
 578         if (scan->prune_min) {
 579                 t = time(NULL);
 580                 for (i = scan->prune.nelms - 1; i >= 0; --i) {
 581                         elm = &scan->prune.elms[i];
 582                         if (elm->mod_tid == 0)
 583                                 continue;
 584                         delta = (long)(t - (time_t)elm->mod_tid);
 585                         if (delta < scan->prune_min)
 586                                 break;
 587                 }
 588                 ++i;
 589                 if (i) {
 590                         printf("Prune %s: prune_min: Will not clean between "
 591                                "the teeth of the first %d snapshots\n",
 592                                scan->filesystem, i);
 593                         bcopy(&scan->prune.elms[i], &scan->prune.elms[0],
 594                               (scan->prune.nelms - i) * sizeof(scan->prune.elms[0]));
 595                         scan->prune.elms[0].end_tid = HAMMER_MAX_TID;
 596                         scan->prune.nelms -= i;
 597                 }
 598         }
 599
 600         /*
 601          * Remove the first entry.  This entry represents the prune from
 602          * the most recent snapshot to current.  We wish to retain the
 603          * fine-grained history for this region.
 604          */
 605         if (scan->prune.nelms) {
 606                 bcopy(&scan->prune.elms[1], &scan->prune.elms[0],
 607                       (scan->prune.nelms - 1) * sizeof(scan->prune.elms[0]));
 608                 --scan->prune.nelms;
 609         }
 610
 611         /*
 612          * Add a final element to prune everything from transaction id
 613          * 0 to the lowest transaction id (aka last so far).
 614          */
 615         if (scan->prune.nelms) {
 616                 assert(scan->prune.nelms < scan->maxelms);
 617                 elm = &scan->prune.elms[scan->prune.nelms];
 618                 elm->beg_tid = 1;
 619                 elm->end_tid = elm[-1].beg_tid;
 620                 ++scan->prune.nelms;
 621         }
 622
 623         /*
 624          * Adjust mod_tid to what the ioctl() expects.
 625          */
 626         for (i = 0; i < scan->prune.nelms; ++i) {
 627                 elm = &scan->prune.elms[i];
 628                 elm->mod_tid = elm->end_tid - elm->beg_tid;
 629                 printf("TID %016jx - %016jx\n",
 630                        (uintmax_t)elm->beg_tid, (uintmax_t)elm->end_tid);
 631         }
 632 }
 633
 634 static
 635 void
 636 softprune_usage(int code)
 637 {
 638         fprintf(stderr, "Badly formed prune command, use:\n");
 639         fprintf(stderr, "hammer prune <softlink-dir>\n");
 640         fprintf(stderr, "hammer prune-everything <filesystem>\n");
 641         exit(code);
 642 }
 643