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 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <dlfcn.h>
28 #include <errno.h>
29 #include <libintl.h>
30 #include <link.h>
31 #include <pthread.h>
32 #include <strings.h>
33 #include <unistd.h>
34 
35 #include <libzfs.h>
36 
37 #include <fm/libtopo.h>
38 #include <sys/fm/protocol.h>
39 #include <sys/systeminfo.h>
40 
41 #include "libzfs_impl.h"
42 
43 /*
44  * This file is responsible for determining the relationship between I/O
45  * devices paths and physical locations.  In the world of MPxIO and external
46  * enclosures, the device path is not synonymous with the physical location.
47  * If you remove a drive and insert it into a different slot, it will end up
48  * with the same path under MPxIO.  If you recable storage enclosures, the
49  * device paths may change.  All of this makes it difficult to implement the
50  * 'autoreplace' property, which is supposed to automatically manage disk
51  * replacement based on physical slot.
52  *
53  * In order to work around these limitations, we have a per-vdev FRU property
54  * that is the libtopo path (minus disk-specific authority information) to the
55  * physical location of the device on the system.  This is an optional
56  * property, and is only needed when using the 'autoreplace' property or when
57  * generating FMA faults against vdevs.
58  */
59 
60 /*
61  * Because the FMA packages depend on ZFS, we have to dlopen() libtopo in case
62  * it is not present.  We only need this once per library instance, so it is
63  * not part of the libzfs handle.
64  */
65 static void *_topo_dlhandle;
66 static topo_hdl_t *(*_topo_open)(int, const char *, int *);
67 static void (*_topo_close)(topo_hdl_t *);
68 static char *(*_topo_snap_hold)(topo_hdl_t *, const char *, int *);
69 static void (*_topo_snap_release)(topo_hdl_t *);
70 static topo_walk_t *(*_topo_walk_init)(topo_hdl_t *, const char *,
71     topo_walk_cb_t, void *, int *);
72 static int (*_topo_walk_step)(topo_walk_t *, int);
73 static void (*_topo_walk_fini)(topo_walk_t *);
74 static void (*_topo_hdl_strfree)(topo_hdl_t *, char *);
75 static char *(*_topo_node_name)(tnode_t *);
76 static int (*_topo_prop_get_string)(tnode_t *, const char *, const char *,
77     char **, int *);
78 static int (*_topo_node_fru)(tnode_t *, nvlist_t **, nvlist_t *, int *);
79 static int (*_topo_fmri_nvl2str)(topo_hdl_t *, nvlist_t *, char **, int *);
80 static int (*_topo_fmri_strcmp_noauth)(topo_hdl_t *, const char *,
81     const char *);
82 
83 #define   ZFS_FRU_HASH_SIZE   257
84 
85 static size_t
fru_strhash(const char * key)86 fru_strhash(const char *key)
87 {
88           ulong_t g, h = 0;
89           const char *p;
90 
91           for (p = key; *p != '\0'; p++) {
92                     h = (h << 4) + *p;
93 
94                     if ((g = (h & 0xf0000000)) != 0) {
95                               h ^= (g >> 24);
96                               h ^= g;
97                     }
98           }
99 
100           return (h % ZFS_FRU_HASH_SIZE);
101 }
102 
103 static int
libzfs_fru_gather(topo_hdl_t * thp,tnode_t * tn,void * arg)104 libzfs_fru_gather(topo_hdl_t *thp, tnode_t *tn, void *arg)
105 {
106           libzfs_handle_t *hdl = arg;
107           nvlist_t *fru;
108           char *devpath, *frustr;
109           int err;
110           libzfs_fru_t *frup;
111           size_t idx;
112 
113           /*
114            * If this is the chassis node, and we don't yet have the system
115            * chassis ID, then fill in this value now.
116            */
117           if (hdl->libzfs_chassis_id[0] == '\0' &&
118               strcmp(_topo_node_name(tn), "chassis") == 0) {
119                     if (_topo_prop_get_string(tn, FM_FMRI_AUTHORITY,
120                         FM_FMRI_AUTH_CHASSIS, &devpath, &err) == 0)
121                               (void) strlcpy(hdl->libzfs_chassis_id, devpath,
122                                   sizeof (hdl->libzfs_chassis_id));
123           }
124 
125           /*
126            * Skip non-disk nodes.
127            */
128           if (strcmp(_topo_node_name(tn), "disk") != 0)
129                     return (TOPO_WALK_NEXT);
130 
131           /*
132            * Get the devfs path and FRU.
133            */
134           if (_topo_prop_get_string(tn, "io", "devfs-path", &devpath, &err) != 0)
135                     return (TOPO_WALK_NEXT);
136 
137           if (libzfs_fru_lookup(hdl, devpath) != NULL) {
138                     _topo_hdl_strfree(thp, devpath);
139                     return (TOPO_WALK_NEXT);
140           }
141 
142           if (_topo_node_fru(tn, &fru, NULL, &err) != 0) {
143                     _topo_hdl_strfree(thp, devpath);
144                     return (TOPO_WALK_NEXT);
145           }
146 
147           /*
148            * Convert the FRU into a string.
149            */
150           if (_topo_fmri_nvl2str(thp, fru, &frustr, &err) != 0) {
151                     nvlist_free(fru);
152                     _topo_hdl_strfree(thp, devpath);
153                     return (TOPO_WALK_NEXT);
154           }
155 
156           nvlist_free(fru);
157 
158           /*
159            * Finally, we have a FRU string and device path.  Add it to the hash.
160            */
161           if ((frup = calloc(sizeof (libzfs_fru_t), 1)) == NULL) {
162                     _topo_hdl_strfree(thp, devpath);
163                     _topo_hdl_strfree(thp, frustr);
164                     return (TOPO_WALK_NEXT);
165           }
166 
167           if ((frup->zf_device = strdup(devpath)) == NULL ||
168               (frup->zf_fru = strdup(frustr)) == NULL) {
169                     free(frup->zf_device);
170                     free(frup);
171                     _topo_hdl_strfree(thp, devpath);
172                     _topo_hdl_strfree(thp, frustr);
173                     return (TOPO_WALK_NEXT);
174           }
175 
176           _topo_hdl_strfree(thp, devpath);
177           _topo_hdl_strfree(thp, frustr);
178 
179           idx = fru_strhash(frup->zf_device);
180           frup->zf_chain = hdl->libzfs_fru_hash[idx];
181           hdl->libzfs_fru_hash[idx] = frup;
182           frup->zf_next = hdl->libzfs_fru_list;
183           hdl->libzfs_fru_list = frup;
184 
185           return (TOPO_WALK_NEXT);
186 }
187 
188 /*
189  * Called during initialization to setup the dynamic libtopo connection.
190  */
191 #pragma init(libzfs_init_fru)
192 static void
libzfs_init_fru(void)193 libzfs_init_fru(void)
194 {
195           char path[MAXPATHLEN];
196           char isa[257];
197 
198 #if defined(_LP64)
199           if (sysinfo(SI_ARCHITECTURE_64, isa, sizeof (isa)) < 0)
200                     isa[0] = '\0';
201 #else
202           isa[0] = '\0';
203 #endif
204           (void) snprintf(path, sizeof (path),
205               "/usr/lib/fm/%s/libtopo.so", isa);
206 
207           if ((_topo_dlhandle = dlopen(path, RTLD_LAZY)) == NULL)
208                     return;
209 
210           _topo_open = (topo_hdl_t *(*)())
211               dlsym(_topo_dlhandle, "topo_open");
212           _topo_close = (void (*)())
213               dlsym(_topo_dlhandle, "topo_close");
214           _topo_snap_hold = (char *(*)())
215               dlsym(_topo_dlhandle, "topo_snap_hold");
216           _topo_snap_release = (void (*)())
217               dlsym(_topo_dlhandle, "topo_snap_release");
218           _topo_walk_init = (topo_walk_t *(*)())
219               dlsym(_topo_dlhandle, "topo_walk_init");
220           _topo_walk_step = (int (*)())
221               dlsym(_topo_dlhandle, "topo_walk_step");
222           _topo_walk_fini = (void (*)())
223               dlsym(_topo_dlhandle, "topo_walk_fini");
224           _topo_hdl_strfree = (void (*)())
225               dlsym(_topo_dlhandle, "topo_hdl_strfree");
226           _topo_node_name = (char *(*)())
227               dlsym(_topo_dlhandle, "topo_node_name");
228           _topo_prop_get_string = (int (*)())
229               dlsym(_topo_dlhandle, "topo_prop_get_string");
230           _topo_node_fru = (int (*)())
231               dlsym(_topo_dlhandle, "topo_node_fru");
232           _topo_fmri_nvl2str = (int (*)())
233               dlsym(_topo_dlhandle, "topo_fmri_nvl2str");
234           _topo_fmri_strcmp_noauth = (int (*)())
235               dlsym(_topo_dlhandle, "topo_fmri_strcmp_noauth");
236 
237           if (_topo_open == NULL || _topo_close == NULL ||
238               _topo_snap_hold == NULL || _topo_snap_release == NULL ||
239               _topo_walk_init == NULL || _topo_walk_step == NULL ||
240               _topo_walk_fini == NULL || _topo_hdl_strfree == NULL ||
241               _topo_node_name == NULL || _topo_prop_get_string == NULL ||
242               _topo_node_fru == NULL || _topo_fmri_nvl2str == NULL ||
243               _topo_fmri_strcmp_noauth == NULL) {
244                     (void) dlclose(_topo_dlhandle);
245                     _topo_dlhandle = NULL;
246           }
247 }
248 
249 /*
250  * Refresh the mappings from device path -> FMRI.  We do this by walking the
251  * hc topology looking for disk nodes, and recording the io/devfs-path and FRU.
252  * Note that we strip out the disk-specific authority information (serial,
253  * part, revision, etc) so that we are left with only the identifying
254  * characteristics of the slot (hc path and chassis-id).
255  */
256 void
libzfs_fru_refresh(libzfs_handle_t * hdl)257 libzfs_fru_refresh(libzfs_handle_t *hdl)
258 {
259           int err;
260           char *uuid;
261           topo_hdl_t *thp;
262           topo_walk_t *twp;
263 
264           if (_topo_dlhandle == NULL)
265                     return;
266 
267           /*
268            * Clear the FRU hash and initialize our basic structures.
269            */
270           libzfs_fru_clear(hdl, B_FALSE);
271 
272           if ((hdl->libzfs_topo_hdl = _topo_open(TOPO_VERSION,
273               NULL, &err)) == NULL)
274                     return;
275 
276           thp = hdl->libzfs_topo_hdl;
277 
278           if ((uuid = _topo_snap_hold(thp, NULL, &err)) == NULL)
279                     return;
280 
281           _topo_hdl_strfree(thp, uuid);
282 
283           if (hdl->libzfs_fru_hash == NULL &&
284               (hdl->libzfs_fru_hash =
285               calloc(ZFS_FRU_HASH_SIZE * sizeof (void *), 1)) == NULL)
286                     return;
287 
288           /*
289            * We now have a topo snapshot, so iterate over the hc topology looking
290            * for disks to add to the hash.
291            */
292           twp = _topo_walk_init(thp, FM_FMRI_SCHEME_HC,
293               libzfs_fru_gather, hdl, &err);
294           if (twp != NULL) {
295                     (void) _topo_walk_step(twp, TOPO_WALK_CHILD);
296                     _topo_walk_fini(twp);
297           }
298 }
299 
300 /*
301  * Given a devfs path, return the FRU for the device, if known.  This will
302  * automatically call libzfs_fru_refresh() if it hasn't already been called by
303  * the consumer.  The string returned is valid until the next call to
304  * libzfs_fru_refresh().
305  */
306 const char *
libzfs_fru_lookup(libzfs_handle_t * hdl,const char * devpath)307 libzfs_fru_lookup(libzfs_handle_t *hdl, const char *devpath)
308 {
309           size_t idx = fru_strhash(devpath);
310           libzfs_fru_t *frup;
311 
312           if (hdl->libzfs_fru_hash == NULL)
313                     libzfs_fru_refresh(hdl);
314 
315           if (hdl->libzfs_fru_hash == NULL)
316                     return (NULL);
317 
318           for (frup = hdl->libzfs_fru_hash[idx]; frup != NULL;
319               frup = frup->zf_chain) {
320                     if (strcmp(devpath, frup->zf_device) == 0)
321                               return (frup->zf_fru);
322           }
323 
324           return (NULL);
325 }
326 
327 /*
328  * Given a fru path, return the device path.  This will automatically call
329  * libzfs_fru_refresh() if it hasn't already been called by the consumer.  The
330  * string returned is valid until the next call to libzfs_fru_refresh().
331  */
332 const char *
libzfs_fru_devpath(libzfs_handle_t * hdl,const char * fru)333 libzfs_fru_devpath(libzfs_handle_t *hdl, const char *fru)
334 {
335           libzfs_fru_t *frup;
336           size_t idx;
337 
338           if (hdl->libzfs_fru_hash == NULL)
339                     libzfs_fru_refresh(hdl);
340 
341           if (hdl->libzfs_fru_hash == NULL)
342                     return (NULL);
343 
344           for (idx = 0; idx < ZFS_FRU_HASH_SIZE; idx++) {
345                     for (frup = hdl->libzfs_fru_hash[idx]; frup != NULL;
346                         frup = frup->zf_next) {
347                               if (_topo_fmri_strcmp_noauth(hdl->libzfs_topo_hdl,
348                                   fru, frup->zf_fru))
349                                         return (frup->zf_device);
350                     }
351           }
352 
353           return (NULL);
354 }
355 
356 /*
357  * Change the stored FRU for the given vdev.
358  */
359 int
zpool_fru_set(zpool_handle_t * zhp,uint64_t vdev_guid,const char * fru)360 zpool_fru_set(zpool_handle_t *zhp, uint64_t vdev_guid, const char *fru)
361 {
362           zfs_cmd_t zc = { 0 };
363 
364           (void) strncpy(zc.zc_name, zhp->zpool_name, sizeof (zc.zc_name));
365           (void) strncpy(zc.zc_value, fru, sizeof (zc.zc_value));
366           zc.zc_guid = vdev_guid;
367 
368           if (zfs_ioctl(zhp->zpool_hdl, ZFS_IOC_VDEV_SETFRU, &zc) != 0)
369                     return (zpool_standard_error_fmt(zhp->zpool_hdl, errno,
370                         dgettext(TEXT_DOMAIN, "cannot set FRU")));
371 
372           return (0);
373 }
374 
375 /*
376  * Compare to two FRUs, ignoring any authority information.
377  */
378 boolean_t
libzfs_fru_compare(libzfs_handle_t * hdl,const char * a,const char * b)379 libzfs_fru_compare(libzfs_handle_t *hdl, const char *a, const char *b)
380 {
381           if (hdl->libzfs_fru_hash == NULL)
382                     libzfs_fru_refresh(hdl);
383 
384           if (hdl->libzfs_fru_hash == NULL)
385                     return (strcmp(a, b) == 0);
386 
387           return (_topo_fmri_strcmp_noauth(hdl->libzfs_topo_hdl, a, b));
388 }
389 
390 /*
391  * This special function checks to see whether the FRU indicates it's supposed
392  * to be in the system chassis, but the chassis-id doesn't match.  This can
393  * happen in a clustered case, where both head nodes have the same logical
394  * disk, but opening the device on the other head node is meaningless.
395  */
396 boolean_t
libzfs_fru_notself(libzfs_handle_t * hdl,const char * fru)397 libzfs_fru_notself(libzfs_handle_t *hdl, const char *fru)
398 {
399           const char *chassisid;
400           size_t len;
401 
402           if (hdl->libzfs_fru_hash == NULL)
403                     libzfs_fru_refresh(hdl);
404 
405           if (hdl->libzfs_chassis_id[0] == '\0')
406                     return (B_FALSE);
407 
408           if (strstr(fru, "/chassis=0/") == NULL)
409                     return (B_FALSE);
410 
411           if ((chassisid = strstr(fru, ":chassis-id=")) == NULL)
412                     return (B_FALSE);
413 
414           chassisid += 12;
415           len = strlen(hdl->libzfs_chassis_id);
416           if (strncmp(chassisid, hdl->libzfs_chassis_id, len) == 0 &&
417               (chassisid[len] == '/' || chassisid[len] == ':'))
418                     return (B_FALSE);
419 
420           return (B_TRUE);
421 }
422 
423 /*
424  * Clear memory associated with the FRU hash.
425  */
426 void
libzfs_fru_clear(libzfs_handle_t * hdl,boolean_t final)427 libzfs_fru_clear(libzfs_handle_t *hdl, boolean_t final)
428 {
429           libzfs_fru_t *frup;
430 
431           while ((frup = hdl->libzfs_fru_list) != NULL) {
432                     hdl->libzfs_fru_list = frup->zf_next;
433                     free(frup->zf_device);
434                     free(frup->zf_fru);
435                     free(frup);
436           }
437 
438           hdl->libzfs_fru_list = NULL;
439 
440           if (hdl->libzfs_topo_hdl != NULL) {
441                     _topo_snap_release(hdl->libzfs_topo_hdl);
442                     _topo_close(hdl->libzfs_topo_hdl);
443                     hdl->libzfs_topo_hdl = NULL;
444           }
445 
446           if (final) {
447                     free(hdl->libzfs_fru_hash);
448           } else if (hdl->libzfs_fru_hash != NULL) {
449                     bzero(hdl->libzfs_fru_hash,
450                         ZFS_FRU_HASH_SIZE * sizeof (void *));
451           }
452 }
453