4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
23 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
33 #include <sys/types.h>
43 #include <sys/zfs_ioctl.h>
45 #include "libzfs_impl.h"
47 #define ZDIFF_SNAPDIR "/.zfs/snapshot/"
48 #define ZDIFF_SHARESDIR "/.zfs/shares/"
49 #define ZDIFF_PREFIX "zfs-diff-%d"
51 #define ZDIFF_ADDED '+'
52 #define ZDIFF_MODIFIED 'M'
53 #define ZDIFF_REMOVED '-'
54 #define ZDIFF_RENAMED 'R'
57 do_name_cmp(const char *fpath, const char *tpath)
60 fname = strrchr(fpath, '/') + 1;
61 tname = strrchr(tpath, '/') + 1;
62 return (strcmp(fname, tname) == 0);
65 typedef struct differ_info {
78 boolean_t timestamped;
87 * Given a {dsname, object id}, get the object path
90 get_stats_for_obj(differ_info_t *di, const char *dsname, uint64_t obj,
91 char *pn, int maxlen, zfs_stat_t *sb)
96 (void) strlcpy(zc.zc_name, dsname, sizeof (zc.zc_name));
100 error = ioctl(di->zhp->zfs_hdl->libzfs_fd, ZFS_IOC_OBJ_TO_STATS, &zc);
103 /* we can get stats even if we failed to get a path */
104 (void) memcpy(sb, &zc.zc_stat, sizeof (zfs_stat_t));
106 ASSERT(di->zerr == 0);
107 (void) strlcpy(pn, zc.zc_value, maxlen);
111 if (di->zerr == EPERM) {
112 (void) snprintf(di->errbuf, sizeof (di->errbuf),
113 dgettext(TEXT_DOMAIN,
114 "The sys_config privilege or diff delegated permission "
115 "is needed\nto discover path names"));
118 (void) snprintf(di->errbuf, sizeof (di->errbuf),
119 dgettext(TEXT_DOMAIN,
120 "Unable to determine path or stats for "
121 "object %lld in %s"), (longlong_t)obj, dsname);
129 * Prints a file name out a character at a time. If the character is
130 * not in the range of what we consider "printable" ASCII, display it
131 * as an escaped 3-digit octal value. ASCII values less than a space
132 * are all control characters and we declare the upper end as the
133 * DELete character. This also is the last 7-bit ASCII character.
134 * We choose to treat all 8-bit ASCII as not printable for this
138 stream_bytes(FILE *fp, const char *string)
141 if (*string > ' ' && *string != '\\' && *string < '\177')
142 (void) fprintf(fp, "%c", *string++);
144 (void) fprintf(fp, "\\%03o", *string++);
149 print_what(FILE *fp, mode_t what)
153 switch (what & S_IFMT) {
185 (void) fprintf(fp, "%c", symbol);
189 print_cmn(FILE *fp, differ_info_t *di, const char *file)
191 stream_bytes(fp, di->dsmnt);
192 stream_bytes(fp, file);
196 print_rename(FILE *fp, differ_info_t *di, const char *old, const char *new,
200 (void) fprintf(fp, "%10lld.%09lld\t",
201 (longlong_t)isb->zs_ctime[0],
202 (longlong_t)isb->zs_ctime[1]);
203 (void) fprintf(fp, "%c\t", ZDIFF_RENAMED);
205 print_what(fp, isb->zs_mode);
206 (void) fprintf(fp, "\t");
208 print_cmn(fp, di, old);
210 (void) fprintf(fp, "\t");
212 (void) fprintf(fp, " -> ");
213 print_cmn(fp, di, new);
214 (void) fprintf(fp, "\n");
218 print_link_change(FILE *fp, differ_info_t *di, int delta, const char *file,
222 (void) fprintf(fp, "%10lld.%09lld\t",
223 (longlong_t)isb->zs_ctime[0],
224 (longlong_t)isb->zs_ctime[1]);
225 (void) fprintf(fp, "%c\t", ZDIFF_MODIFIED);
227 print_what(fp, isb->zs_mode);
228 (void) fprintf(fp, "\t");
230 print_cmn(fp, di, file);
231 (void) fprintf(fp, "\t(%+d)", delta);
232 (void) fprintf(fp, "\n");
236 print_file(FILE *fp, differ_info_t *di, char type, const char *file,
240 (void) fprintf(fp, "%10lld.%09lld\t",
241 (longlong_t)isb->zs_ctime[0],
242 (longlong_t)isb->zs_ctime[1]);
243 (void) fprintf(fp, "%c\t", type);
245 print_what(fp, isb->zs_mode);
246 (void) fprintf(fp, "\t");
248 print_cmn(fp, di, file);
249 (void) fprintf(fp, "\n");
253 write_inuse_diffs_one(FILE *fp, differ_info_t *di, uint64_t dobj)
255 struct zfs_stat fsb, tsb;
258 char fobjname[MAXPATHLEN], tobjname[MAXPATHLEN];
259 int fobjerr, tobjerr;
262 if (dobj == di->shares)
266 * Check the from and to snapshots for info on the object. If
267 * we get ENOENT, then the object just didn't exist in that
268 * snapshot. If we get ENOTSUP, then we tried to get
269 * info on a non-ZPL object, which we don't care about anyway.
271 fobjerr = get_stats_for_obj(di, di->fromsnap, dobj, fobjname,
273 if (fobjerr && di->zerr != ENOENT && di->zerr != ENOTSUP)
276 tobjerr = get_stats_for_obj(di, di->tosnap, dobj, tobjname,
278 if (tobjerr && di->zerr != ENOENT && di->zerr != ENOTSUP)
282 * Unallocated object sharing the same meta dnode block
284 if (fobjerr && tobjerr) {
285 ASSERT(di->zerr == ENOENT || di->zerr == ENOTSUP);
290 di->zerr = 0; /* negate get_stats_for_obj() from side that failed */
291 fmode = fsb.zs_mode & S_IFMT;
292 tmode = tsb.zs_mode & S_IFMT;
293 if (fmode == S_IFDIR || tmode == S_IFDIR || fsb.zs_links == 0 ||
297 change = tsb.zs_links - fsb.zs_links;
301 print_link_change(fp, di, change, tobjname, &tsb);
304 print_file(fp, di, ZDIFF_ADDED, tobjname, &tsb);
306 } else if (tobjerr) {
308 print_link_change(fp, di, change, fobjname, &fsb);
311 print_file(fp, di, ZDIFF_REMOVED, fobjname, &fsb);
315 if (fmode != tmode && fsb.zs_gen == tsb.zs_gen)
316 tsb.zs_gen++; /* Force a generational difference */
317 same_name = do_name_cmp(fobjname, tobjname);
319 /* Simple modification or no change */
320 if (fsb.zs_gen == tsb.zs_gen) {
321 /* No apparent changes. Could we assert !this? */
322 if (fsb.zs_ctime[0] == tsb.zs_ctime[0] &&
323 fsb.zs_ctime[1] == tsb.zs_ctime[1])
326 print_link_change(fp, di, change,
327 change > 0 ? fobjname : tobjname, &tsb);
328 } else if (same_name) {
329 print_file(fp, di, ZDIFF_MODIFIED, fobjname, &tsb);
331 print_rename(fp, di, fobjname, tobjname, &tsb);
335 /* file re-created or object re-used */
336 print_file(fp, di, ZDIFF_REMOVED, fobjname, &fsb);
337 print_file(fp, di, ZDIFF_ADDED, tobjname, &tsb);
343 write_inuse_diffs(FILE *fp, differ_info_t *di, dmu_diff_record_t *dr)
348 for (o = dr->ddr_first; o <= dr->ddr_last; o++) {
349 if (err = write_inuse_diffs_one(fp, di, o))
356 describe_free(FILE *fp, differ_info_t *di, uint64_t object, char *namebuf,
361 if (get_stats_for_obj(di, di->fromsnap, object, namebuf,
363 /* Let it slide, if in the delete queue on from side */
364 if (di->zerr == ENOENT && sb.zs_links == 0) {
371 print_file(fp, di, ZDIFF_REMOVED, namebuf, &sb);
376 write_free_diffs(FILE *fp, differ_info_t *di, dmu_diff_record_t *dr)
378 zfs_cmd_t zc = { 0 };
379 libzfs_handle_t *lhdl = di->zhp->zfs_hdl;
380 char fobjname[MAXPATHLEN];
382 (void) strlcpy(zc.zc_name, di->fromsnap, sizeof (zc.zc_name));
383 zc.zc_obj = dr->ddr_first - 1;
385 ASSERT(di->zerr == 0);
387 while (zc.zc_obj < dr->ddr_last) {
390 err = ioctl(lhdl->libzfs_fd, ZFS_IOC_NEXT_OBJ, &zc);
392 if (zc.zc_obj == di->shares) {
396 if (zc.zc_obj > dr->ddr_last) {
399 err = describe_free(fp, di, zc.zc_obj, fobjname,
403 } else if (errno == ESRCH) {
406 (void) snprintf(di->errbuf, sizeof (di->errbuf),
407 dgettext(TEXT_DOMAIN,
408 "next allocated object (> %lld) find failure"),
409 (longlong_t)zc.zc_obj);
422 differ_info_t *di = arg;
423 dmu_diff_record_t dr;
427 if ((ofp = fdopen(di->outputfd, "w")) == NULL) {
429 (void) strerror_r(errno, di->errbuf, sizeof (di->errbuf));
430 (void) close(di->datafd);
435 char *cp = (char *)&dr;
436 int len = sizeof (dr);
440 rv = read(di->datafd, cp, len);
443 } while (len > 0 && rv > 0);
445 if (rv < 0 || (rv == 0 && len != sizeof (dr))) {
448 } else if (rv == 0) {
449 /* end of file at a natural breaking point */
453 switch (dr.ddr_type) {
455 err = write_free_diffs(ofp, di, &dr);
458 err = write_inuse_diffs(ofp, di, &dr);
470 (void) close(di->datafd);
474 ASSERT(di->zerr == EINVAL);
475 (void) snprintf(di->errbuf, sizeof (di->errbuf),
476 dgettext(TEXT_DOMAIN,
477 "Internal error: bad data from diff IOCTL"));
484 find_shares_object(differ_info_t *di)
486 char fullpath[MAXPATHLEN];
487 struct stat64 sb = { 0 };
489 (void) strlcpy(fullpath, di->dsmnt, MAXPATHLEN);
490 (void) strlcat(fullpath, ZDIFF_SHARESDIR, MAXPATHLEN);
492 if (stat64(fullpath, &sb) != 0) {
493 (void) snprintf(di->errbuf, sizeof (di->errbuf),
494 dgettext(TEXT_DOMAIN, "Cannot stat %s"), fullpath);
495 return (zfs_error(di->zhp->zfs_hdl, EZFS_DIFF, di->errbuf));
498 di->shares = (uint64_t)sb.st_ino;
503 make_temp_snapshot(differ_info_t *di)
505 libzfs_handle_t *hdl = di->zhp->zfs_hdl;
506 zfs_cmd_t zc = { 0 };
508 (void) snprintf(zc.zc_value, sizeof (zc.zc_value),
509 ZDIFF_PREFIX, getpid());
510 (void) strlcpy(zc.zc_name, di->ds, sizeof (zc.zc_name));
511 zc.zc_cleanup_fd = di->cleanupfd;
513 if (ioctl(hdl->libzfs_fd, ZFS_IOC_TMP_SNAPSHOT, &zc) != 0) {
516 (void) snprintf(di->errbuf, sizeof (di->errbuf),
517 dgettext(TEXT_DOMAIN, "The diff delegated "
518 "permission is needed in order\nto create a "
519 "just-in-time snapshot for diffing\n"));
520 return (zfs_error(hdl, EZFS_DIFF, di->errbuf));
522 (void) snprintf(di->errbuf, sizeof (di->errbuf),
523 dgettext(TEXT_DOMAIN, "Cannot create just-in-time "
524 "snapshot of '%s'"), zc.zc_name);
525 return (zfs_standard_error(hdl, err, di->errbuf));
529 di->tmpsnap = zfs_strdup(hdl, zc.zc_value);
530 di->tosnap = zfs_asprintf(hdl, "%s@%s", di->ds, di->tmpsnap);
535 teardown_differ_info(differ_info_t *di)
544 (void) close(di->cleanupfd);
548 get_snapshot_names(differ_info_t *di, const char *fromsnap,
551 libzfs_handle_t *hdl = di->zhp->zfs_hdl;
560 * dataset@snap1 dataset@snap2
561 * dataset@snap1 @snap2
562 * dataset@snap1 dataset
563 * @snap1 dataset@snap2
565 if (tosnap == NULL) {
566 /* only a from snapshot given, must be valid */
567 (void) snprintf(di->errbuf, sizeof (di->errbuf),
568 dgettext(TEXT_DOMAIN,
569 "Badly formed snapshot name %s"), fromsnap);
571 if (!zfs_validate_name(hdl, fromsnap, ZFS_TYPE_SNAPSHOT,
573 return (zfs_error(hdl, EZFS_INVALIDNAME,
577 atptrf = strchr(fromsnap, '@');
578 ASSERT(atptrf != NULL);
579 fdslen = atptrf - fromsnap;
581 di->fromsnap = zfs_strdup(hdl, fromsnap);
582 di->ds = zfs_strdup(hdl, fromsnap);
583 di->ds[fdslen] = '\0';
585 /* the to snap will be a just-in-time snap of the head */
586 return (make_temp_snapshot(di));
589 (void) snprintf(di->errbuf, sizeof (di->errbuf),
590 dgettext(TEXT_DOMAIN,
591 "Unable to determine which snapshots to compare"));
593 atptrf = strchr(fromsnap, '@');
594 atptrt = strchr(tosnap, '@');
595 fdslen = atptrf ? atptrf - fromsnap : strlen(fromsnap);
596 tdslen = atptrt ? atptrt - tosnap : strlen(tosnap);
597 fsnlen = strlen(fromsnap) - fdslen; /* includes @ sign */
598 tsnlen = strlen(tosnap) - tdslen; /* includes @ sign */
600 if (fsnlen <= 1 || tsnlen == 1 || (fdslen == 0 && tdslen == 0) ||
601 (fsnlen == 0 && tsnlen == 0)) {
602 return (zfs_error(hdl, EZFS_INVALIDNAME, di->errbuf));
603 } else if ((fdslen > 0 && tdslen > 0) &&
604 ((tdslen != fdslen || strncmp(fromsnap, tosnap, fdslen) != 0))) {
606 * not the same dataset name, might be okay if
607 * tosnap is a clone of a fromsnap descendant.
609 char origin[ZFS_MAXNAMELEN];
613 di->ds = zfs_alloc(di->zhp->zfs_hdl, tdslen + 1);
614 (void) strncpy(di->ds, tosnap, tdslen);
615 di->ds[tdslen] = '\0';
617 zhp = zfs_open(hdl, di->ds, ZFS_TYPE_FILESYSTEM);
618 while (zhp != NULL) {
619 (void) zfs_prop_get(zhp, ZFS_PROP_ORIGIN,
620 origin, sizeof (origin), &src, NULL, 0, B_FALSE);
622 if (strncmp(origin, fromsnap, fsnlen) == 0)
625 (void) zfs_close(zhp);
626 zhp = zfs_open(hdl, origin, ZFS_TYPE_FILESYSTEM);
630 (void) snprintf(di->errbuf, sizeof (di->errbuf),
631 dgettext(TEXT_DOMAIN,
632 "Not an earlier snapshot from the same fs"));
633 return (zfs_error(hdl, EZFS_INVALIDNAME, di->errbuf));
635 (void) zfs_close(zhp);
638 di->isclone = B_TRUE;
639 di->fromsnap = zfs_strdup(hdl, fromsnap);
641 di->tosnap = zfs_strdup(hdl, tosnap);
643 return (make_temp_snapshot(di));
646 int dslen = fdslen ? fdslen : tdslen;
648 di->ds = zfs_alloc(hdl, dslen + 1);
649 (void) strncpy(di->ds, fdslen ? fromsnap : tosnap, dslen);
650 di->ds[dslen] = '\0';
652 di->fromsnap = zfs_asprintf(hdl, "%s%s", di->ds, atptrf);
654 di->tosnap = zfs_asprintf(hdl, "%s%s", di->ds, atptrt);
656 return (make_temp_snapshot(di));
663 get_mountpoint(differ_info_t *di, char *dsnm, char **mntpt)
667 mounted = is_mounted(di->zhp->zfs_hdl, dsnm, mntpt);
668 if (mounted == B_FALSE) {
669 (void) snprintf(di->errbuf, sizeof (di->errbuf),
670 dgettext(TEXT_DOMAIN,
671 "Cannot diff an unmounted snapshot"));
672 return (zfs_error(di->zhp->zfs_hdl, EZFS_BADTYPE, di->errbuf));
675 /* Avoid a double slash at the beginning of root-mounted datasets */
676 if (**mntpt == '/' && *(*mntpt + 1) == '\0')
682 get_mountpoints(differ_info_t *di)
688 * first get the mountpoint for the parent dataset
690 if (get_mountpoint(di, di->ds, &di->dsmnt) != 0)
693 strptr = strchr(di->tosnap, '@');
694 ASSERT3P(strptr, !=, NULL);
695 di->tomnt = zfs_asprintf(di->zhp->zfs_hdl, "%s%s%s", di->dsmnt,
696 ZDIFF_SNAPDIR, ++strptr);
698 strptr = strchr(di->fromsnap, '@');
699 ASSERT3P(strptr, !=, NULL);
701 frommntpt = di->dsmnt;
707 err = get_mountpoint(di, di->fromsnap, &mntpt);
714 di->frommnt = zfs_asprintf(di->zhp->zfs_hdl, "%s%s%s", frommntpt,
715 ZDIFF_SNAPDIR, ++strptr);
724 setup_differ_info(zfs_handle_t *zhp, const char *fromsnap,
725 const char *tosnap, differ_info_t *di)
729 di->cleanupfd = open(ZFS_DEV, O_RDWR|O_EXCL);
730 VERIFY(di->cleanupfd >= 0);
732 if (get_snapshot_names(di, fromsnap, tosnap) != 0)
735 if (get_mountpoints(di) != 0)
738 if (find_shares_object(di) != 0)
745 zfs_show_diffs(zfs_handle_t *zhp, int outfd, const char *fromsnap,
746 const char *tosnap, int flags)
748 zfs_cmd_t zc = { 0 };
750 differ_info_t di = { 0 };
755 (void) snprintf(errbuf, sizeof (errbuf),
756 dgettext(TEXT_DOMAIN, "zfs diff failed"));
758 if (setup_differ_info(zhp, fromsnap, tosnap, &di)) {
759 teardown_differ_info(&di);
764 zfs_error_aux(zhp->zfs_hdl, strerror(errno));
765 teardown_differ_info(&di);
766 return (zfs_error(zhp->zfs_hdl, EZFS_PIPEFAILED, errbuf));
769 di.scripted = (flags & ZFS_DIFF_PARSEABLE);
770 di.classify = (flags & ZFS_DIFF_CLASSIFY);
771 di.timestamped = (flags & ZFS_DIFF_TIMESTAMP);
774 di.datafd = pipefd[0];
776 if (pthread_create(&tid, NULL, differ, &di)) {
777 zfs_error_aux(zhp->zfs_hdl, strerror(errno));
778 (void) close(pipefd[0]);
779 (void) close(pipefd[1]);
780 teardown_differ_info(&di);
781 return (zfs_error(zhp->zfs_hdl,
782 EZFS_THREADCREATEFAILED, errbuf));
786 (void) strlcpy(zc.zc_value, di.fromsnap, strlen(di.fromsnap) + 1);
787 (void) strlcpy(zc.zc_name, di.tosnap, strlen(di.tosnap) + 1);
788 zc.zc_cookie = pipefd[1];
790 iocerr = ioctl(zhp->zfs_hdl->libzfs_fd, ZFS_IOC_DIFF, &zc);
792 (void) snprintf(errbuf, sizeof (errbuf),
793 dgettext(TEXT_DOMAIN, "Unable to obtain diffs"));
794 if (errno == EPERM) {
795 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
796 "\n The sys_mount privilege or diff delegated "
797 "permission is needed\n to execute the "
799 } else if (errno == EXDEV) {
800 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
801 "\n Not an earlier snapshot from the same fs"));
802 } else if (errno != EPIPE || di.zerr == 0) {
803 zfs_error_aux(zhp->zfs_hdl, strerror(errno));
805 (void) close(pipefd[1]);
806 (void) pthread_cancel(tid);
807 (void) pthread_join(tid, NULL);
808 teardown_differ_info(&di);
809 if (di.zerr != 0 && di.zerr != EPIPE) {
810 zfs_error_aux(zhp->zfs_hdl, strerror(di.zerr));
811 return (zfs_error(zhp->zfs_hdl, EZFS_DIFF, di.errbuf));
813 return (zfs_error(zhp->zfs_hdl, EZFS_DIFFDATA, errbuf));
817 (void) close(pipefd[1]);
818 (void) pthread_join(tid, NULL);
821 zfs_error_aux(zhp->zfs_hdl, strerror(di.zerr));
822 return (zfs_error(zhp->zfs_hdl, EZFS_DIFF, di.errbuf));
824 teardown_differ_info(&di);