translate.c revision fa94a07fd0519b8abfd871ad8fe60e6bebe1e2bb
1/*
2 * CDDL HEADER START
3 *
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.
7 *
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.
12 *
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]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#pragma ident	"%Z%%M%	%I%	%E% SMI"
27
28#include <libzfs.h>
29
30#undef verify	/* both libzfs.h and zfs_context.h want to define this */
31
32#include <sys/zfs_context.h>
33
34#include <errno.h>
35#include <fcntl.h>
36#include <stdarg.h>
37#include <stddef.h>
38#include <stdio.h>
39#include <stdlib.h>
40#include <strings.h>
41#include <sys/file.h>
42#include <sys/mntent.h>
43#include <sys/mnttab.h>
44#include <sys/param.h>
45#include <sys/stat.h>
46
47#include <sys/dmu.h>
48#include <sys/dmu_objset.h>
49#include <sys/dnode.h>
50
51#include <sys/mkdev.h>
52
53#include "zinject.h"
54
55extern void kernel_init(int);
56extern void kernel_fini(void);
57
58static int debug;
59
60static void
61ziprintf(const char *fmt, ...)
62{
63	va_list ap;
64
65	if (!debug)
66		return;
67
68	va_start(ap, fmt);
69	(void) vprintf(fmt, ap);
70	va_end(ap);
71}
72
73/*
74 * Given a full path to a file, translate into a dataset name and a relative
75 * path within the dataset.  'dataset' must be at least MAXNAMELEN characters,
76 * and 'relpath' must be at least MAXPATHLEN characters.  We also pass a stat64
77 * buffer, which we need later to get the object ID.
78 */
79static int
80parse_pathname(const char *fullpath, char *dataset, char *relpath,
81    struct stat64 *statbuf)
82{
83	struct extmnttab mp;
84	FILE *fp;
85	int match;
86	const char *rel;
87
88	if (fullpath[0] != '/') {
89		(void) fprintf(stderr, "invalid object '%s': must be full "
90		    "path\n", fullpath);
91		usage();
92		return (-1);
93	}
94
95	if (strlen(fullpath) >= MAXPATHLEN) {
96		(void) fprintf(stderr, "invalid object; pathname too long\n");
97		return (-1);
98	}
99
100	if (stat64(fullpath, statbuf) != 0) {
101		(void) fprintf(stderr, "cannot open '%s': %s\n",
102		    fullpath, strerror(errno));
103		return (-1);
104	}
105
106	if ((fp = fopen(MNTTAB, "r")) == NULL) {
107		(void) fprintf(stderr, "cannot open /etc/mnttab\n");
108		return (-1);
109	}
110
111	match = 0;
112	while (getextmntent(fp, &mp, sizeof (mp)) == 0) {
113		if (makedev(mp.mnt_major, mp.mnt_minor) == statbuf->st_dev) {
114			match = 1;
115			break;
116		}
117	}
118
119	if (!match) {
120		(void) fprintf(stderr, "cannot find mountpoint for '%s'\n",
121		    fullpath);
122		return (-1);
123	}
124
125	if (strcmp(mp.mnt_fstype, MNTTYPE_ZFS) != 0) {
126		(void) fprintf(stderr, "invalid path '%s': not a ZFS "
127		    "filesystem\n", fullpath);
128		return (-1);
129	}
130
131	if (strncmp(fullpath, mp.mnt_mountp, strlen(mp.mnt_mountp)) != 0) {
132		(void) fprintf(stderr, "invalid path '%s': mountpoint "
133		    "doesn't match path\n", fullpath);
134		return (-1);
135	}
136
137	(void) strcpy(dataset, mp.mnt_special);
138
139	rel = fullpath + strlen(mp.mnt_mountp);
140	if (rel[0] == '/')
141		rel++;
142	(void) strcpy(relpath, rel);
143
144	return (0);
145}
146
147/*
148 * Convert from a (dataset, path) pair into a (objset, object) pair.  Note that
149 * we grab the object number from the inode number, since looking this up via
150 * libzpool is a real pain.
151 */
152/* ARGSUSED */
153static int
154object_from_path(const char *dataset, const char *path, struct stat64 *statbuf,
155    zinject_record_t *record)
156{
157	objset_t *os;
158	int err;
159
160	/*
161	 * Before doing any libzpool operations, call sync() to ensure that the
162	 * on-disk state is consistent with the in-core state.
163	 */
164	sync();
165
166	if ((err = dmu_objset_open(dataset, DMU_OST_ZFS,
167	    DS_MODE_STANDARD | DS_MODE_READONLY, &os)) != 0) {
168		(void) fprintf(stderr, "cannot open dataset '%s': %s\n",
169		    dataset, strerror(err));
170		return (-1);
171	}
172
173	record->zi_objset = dmu_objset_id(os);
174	record->zi_object = statbuf->st_ino;
175
176	dmu_objset_close(os);
177
178	return (0);
179}
180
181/*
182 * Calculate the real range based on the type, level, and range given.
183 */
184static int
185calculate_range(const char *dataset, err_type_t type, int level, char *range,
186    zinject_record_t *record)
187{
188	objset_t *os = NULL;
189	dnode_t *dn = NULL;
190	int err;
191	int ret = -1;
192
193	/*
194	 * Determine the numeric range from the string.
195	 */
196	if (range == NULL) {
197		/*
198		 * If range is unspecified, set the range to [0,-1], which
199		 * indicates that the whole object should be treated as an
200		 * error.
201		 */
202		record->zi_start = 0;
203		record->zi_end = -1ULL;
204	} else {
205		char *end;
206
207		/* XXX add support for suffixes */
208		record->zi_start = strtoull(range, &end, 10);
209
210
211		if (*end == '\0')
212			record->zi_end = record->zi_start + 1;
213		else if (*end == ',')
214			record->zi_end = strtoull(end + 1, &end, 10);
215
216		if (*end != '\0') {
217			(void) fprintf(stderr, "invalid range '%s': must be "
218			    "a numeric range of the form 'start[,end]'\n",
219			    range);
220			goto out;
221		}
222	}
223
224	switch (type) {
225	case TYPE_DATA:
226		break;
227
228	case TYPE_DNODE:
229		/*
230		 * If this is a request to inject faults into the dnode, then we
231		 * must translate the current (objset,object) pair into an
232		 * offset within the metadnode for the objset.  Specifying any
233		 * kind of range with type 'dnode' is illegal.
234		 */
235		if (range != NULL) {
236			(void) fprintf(stderr, "range cannot be specified when "
237			    "type is 'dnode'\n");
238			goto out;
239		}
240
241		record->zi_start = record->zi_object * sizeof (dnode_phys_t);
242		record->zi_end = record->zi_start + sizeof (dnode_phys_t);
243		record->zi_object = 0;
244		break;
245	}
246
247	/*
248	 * Get the dnode associated with object, so we can calculate the block
249	 * size.
250	 */
251	if ((err = dmu_objset_open(dataset, DMU_OST_ANY,
252	    DS_MODE_STANDARD | DS_MODE_READONLY, &os)) != 0) {
253		(void) fprintf(stderr, "cannot open dataset '%s': %s\n",
254		    dataset, strerror(err));
255		goto out;
256	}
257
258	if (record->zi_object == 0) {
259		dn = os->os->os_meta_dnode;
260	} else {
261		err = dnode_hold(os->os, record->zi_object, FTAG, &dn);
262		if (err != 0) {
263			(void) fprintf(stderr, "failed to hold dnode "
264			    "for object %llu\n",
265			    (u_longlong_t)record->zi_object);
266			goto out;
267		}
268	}
269
270
271	ziprintf("data shift: %d\n", (int)dn->dn_datablkshift);
272	ziprintf(" ind shift: %d\n", (int)dn->dn_indblkshift);
273
274	/*
275	 * Translate range into block IDs.
276	 */
277	if (record->zi_start != 0 || record->zi_end != -1ULL) {
278		record->zi_start >>= dn->dn_datablkshift;
279		record->zi_end >>= dn->dn_datablkshift;
280	}
281
282	/*
283	 * Check level, and then translate level 0 blkids into ranges
284	 * appropriate for level of indirection.
285	 */
286	record->zi_level = level;
287	if (level > 0) {
288		ziprintf("level 0 blkid range: [%llu, %llu]\n",
289		    record->zi_start, record->zi_end);
290
291		if (level >= dn->dn_nlevels) {
292			(void) fprintf(stderr, "level %d exceeds max level "
293			    "of object (%d)\n", level, dn->dn_nlevels - 1);
294			goto out;
295		}
296
297		if (record->zi_start != 0 || record->zi_end != 0) {
298			int shift = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
299
300			for (; level > 0; level--) {
301				record->zi_start >>= shift;
302				record->zi_end >>= shift;
303			}
304		}
305	}
306
307	ret = 0;
308out:
309	if (dn) {
310		if (dn != os->os->os_meta_dnode)
311			dnode_rele(dn, FTAG);
312	}
313	if (os)
314		dmu_objset_close(os);
315
316	return (ret);
317}
318
319int
320translate_record(err_type_t type, const char *object, const char *range,
321    int level, zinject_record_t *record, char *poolname, char *dataset)
322{
323	char path[MAXPATHLEN];
324	char *slash;
325	struct stat64 statbuf;
326	int ret = -1;
327
328	kernel_init(FREAD);
329
330	debug = (getenv("ZINJECT_DEBUG") != NULL);
331
332	ziprintf("translating: %s\n", object);
333
334	if (MOS_TYPE(type)) {
335		/*
336		 * MOS objects are treated specially.
337		 */
338		switch (type) {
339		case TYPE_MOS:
340			record->zi_type = 0;
341			break;
342		case TYPE_MOSDIR:
343			record->zi_type = DMU_OT_OBJECT_DIRECTORY;
344			break;
345		case TYPE_METASLAB:
346			record->zi_type = DMU_OT_OBJECT_ARRAY;
347			break;
348		case TYPE_CONFIG:
349			record->zi_type = DMU_OT_PACKED_NVLIST;
350			break;
351		case TYPE_BPLIST:
352			record->zi_type = DMU_OT_BPLIST;
353			break;
354		case TYPE_SPACEMAP:
355			record->zi_type = DMU_OT_SPACE_MAP;
356			break;
357		case TYPE_ERRLOG:
358			record->zi_type = DMU_OT_ERROR_LOG;
359			break;
360		}
361
362		dataset[0] = '\0';
363		(void) strcpy(poolname, object);
364		return (0);
365	}
366
367	/*
368	 * Convert a full path into a (dataset, file) pair.
369	 */
370	if (parse_pathname(object, dataset, path, &statbuf) != 0)
371		goto err;
372
373	ziprintf("   dataset: %s\n", dataset);
374	ziprintf("      path: %s\n", path);
375
376	/*
377	 * Convert (dataset, file) into (objset, object)
378	 */
379	if (object_from_path(dataset, path, &statbuf, record) != 0)
380		goto err;
381
382	ziprintf("raw objset: %llu\n", record->zi_objset);
383	ziprintf("raw object: %llu\n", record->zi_object);
384
385	/*
386	 * For the given object, calculate the real (type, level, range)
387	 */
388	if (calculate_range(dataset, type, level, (char *)range, record) != 0)
389		goto err;
390
391	ziprintf("    objset: %llu\n", record->zi_objset);
392	ziprintf("    object: %llu\n", record->zi_object);
393	if (record->zi_start == 0 &&
394	    record->zi_end == -1ULL)
395		ziprintf("     range: all\n");
396	else
397		ziprintf("     range: [%llu, %llu]\n", record->zi_start,
398		    record->zi_end);
399
400	/*
401	 * Copy the pool name
402	 */
403	(void) strcpy(poolname, dataset);
404	if ((slash = strchr(poolname, '/')) != NULL)
405		*slash = '\0';
406
407	ret = 0;
408
409err:
410	kernel_fini();
411	return (ret);
412}
413
414int
415translate_raw(const char *str, zinject_record_t *record)
416{
417	/*
418	 * A raw bookmark of the form objset:object:level:blkid, where each
419	 * number is a hexidecimal value.
420	 */
421	if (sscanf(str, "%llx:%llx:%x:%llx", (u_longlong_t *)&record->zi_objset,
422	    (u_longlong_t *)&record->zi_object, &record->zi_level,
423	    (u_longlong_t *)&record->zi_start) != 4) {
424		(void) fprintf(stderr, "bad raw spec '%s': must be of the form "
425		    "'objset:object:level:blkid'\n", str);
426		return (-1);
427	}
428
429	record->zi_end = record->zi_start;
430
431	return (0);
432}
433
434int
435translate_device(const char *pool, const char *device, zinject_record_t *record)
436{
437	char *end;
438	zpool_handle_t *zhp;
439	nvlist_t *tgt;
440	boolean_t isspare, iscache;
441
442	/*
443	 * Given a device name or GUID, create an appropriate injection record
444	 * with zi_guid set.
445	 */
446	if ((zhp = zpool_open(g_zfs, pool)) == NULL)
447		return (-1);
448
449	record->zi_guid = strtoull(device, &end, 16);
450	if (record->zi_guid == 0 || *end != '\0') {
451		tgt = zpool_find_vdev(zhp, device, &isspare, &iscache);
452
453		if (tgt == NULL) {
454			(void) fprintf(stderr, "cannot find device '%s' in "
455			    "pool '%s'\n", device, pool);
456			return (-1);
457		}
458
459		verify(nvlist_lookup_uint64(tgt, ZPOOL_CONFIG_GUID,
460		    &record->zi_guid) == 0);
461	}
462
463	return (0);
464}
465