hostres_storage_tbl.c revision 248707 
1/*-
2 * Copyright (c) 2005-2006 The FreeBSD Project
3 * All rights reserved.
4 *
5 * Author: Victor Cruceru <soc-victor@freebsd.org>
6 *
7 * Redistribution of this software and documentation and use in source and
8 * binary forms, with or without modification, are permitted provided that
9 * the following conditions are met:
10 *
11 * 1. Redistributions of source code or documentation must retain the above
12 *    copyright 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 the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: head/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_storage_tbl.c 248707 2013-03-25 19:12:36Z trociny $
30 */
31
32/*
33 * Host Resources MIB for SNMPd. Implementation for hrStorageTable
34 */
35
36#include <sys/types.h>
37#include <sys/param.h>
38#include <sys/sysctl.h>
39#include <sys/vmmeter.h>
40#include <sys/mount.h>
41
42#include <vm/vm_param.h>
43
44#include <assert.h>
45#include <err.h>
46#include <limits.h>
47#include <memstat.h>
48#include <paths.h>
49#include <stdlib.h>
50#include <string.h>
51#include <syslog.h>
52#include <unistd.h> /* for getpagesize() */
53#include <sysexits.h>
54
55#include "hostres_snmp.h"
56#include "hostres_oid.h"
57#include "hostres_tree.h"
58
59/* maximum length for descritpion string according to MIB */
60#define	SE_DESC_MLEN	(255 + 1)
61
62/*
63 * This structure is used to hold a SNMP table entry
64 * for HOST-RESOURCES-MIB's hrStorageTable
65 */
66struct storage_entry {
67	int32_t		index;
68	const struct asn_oid *type;
69	u_char		*descr;
70	int32_t		allocationUnits;
71	int32_t		size;
72	int32_t		used;
73	uint32_t	allocationFailures;
74#define	HR_STORAGE_FOUND 0x001
75	uint32_t	flags;	/* to be used internally*/
76	TAILQ_ENTRY(storage_entry) link;
77};
78TAILQ_HEAD(storage_tbl, storage_entry);
79
80/*
81 * Next structure is used to keep o list of mappings from a specific name
82 * (a_name) to an entry in the hrStorageTblEntry. We are trying to keep the
83 * same index for a specific name at least for the duration of one SNMP agent
84 * run.
85 */
86struct storage_map_entry {
87	int32_t		hrIndex; /* used for storage_entry::index */
88
89	/* map key, also used for storage_entry::descr */
90	u_char		*a_name;
91
92	/*
93	 * next may be NULL if the respective storage_entry
94	 * is (temporally) gone
95	 */
96	struct storage_entry *entry;
97	STAILQ_ENTRY(storage_map_entry) link;
98};
99STAILQ_HEAD(storage_map, storage_map_entry);
100
101/* the head of the list with table's entries */
102static struct storage_tbl storage_tbl = TAILQ_HEAD_INITIALIZER(storage_tbl);
103
104/*for consistent table indexing*/
105static struct storage_map storage_map =
106    STAILQ_HEAD_INITIALIZER(storage_map);
107
108/* last (agent) tick when hrStorageTable was updated */
109static uint64_t storage_tick;
110
111/* maximum number of ticks between two refreshs */
112uint32_t storage_tbl_refresh = HR_STORAGE_TBL_REFRESH * 100;
113
114/* for kvm_getswapinfo, malloc'd */
115static struct kvm_swap *swap_devs;
116static size_t swap_devs_len;		/* item count for swap_devs */
117
118/* for getfsstat, malloc'd */
119static struct statfs *fs_buf;
120static size_t fs_buf_count;		/* item count for fs_buf */
121
122static struct vmtotal mem_stats;
123
124/* next int available for indexing the hrStorageTable */
125static uint32_t next_storage_index = 1;
126
127/* start of list for memory detailed stats */
128static struct memory_type_list *mt_list;
129
130/* Constants */
131static const struct asn_oid OIDX_hrStorageRam_c = OIDX_hrStorageRam;
132static const struct asn_oid OIDX_hrStorageVirtualMemory_c =
133    OIDX_hrStorageVirtualMemory;
134
135/**
136 * Create a new entry into the storage table and, if necessary, an
137 * entry into the storage map.
138 */
139static struct storage_entry *
140storage_entry_create(const char *name)
141{
142	struct storage_entry *entry;
143	struct storage_map_entry *map;
144	size_t name_len;
145
146	assert(name != NULL);
147	assert(strlen(name) > 0);
148
149	STAILQ_FOREACH(map, &storage_map, link)
150		if (strcmp(map->a_name, name) == 0)
151			break;
152
153	if (map == NULL) {
154		/* new object - get a new index */
155		if (next_storage_index > INT_MAX) {
156		        syslog(LOG_ERR,
157			    "%s: hrStorageTable index wrap", __func__);
158			errx(EX_SOFTWARE, "hrStorageTable index wrap");
159		}
160
161		if ((map = malloc(sizeof(*map))) == NULL) {
162			syslog(LOG_ERR, "hrStorageTable: %s: %m", __func__ );
163			return (NULL);
164		}
165
166		name_len = strlen(name) + 1;
167		if (name_len > SE_DESC_MLEN)
168			name_len = SE_DESC_MLEN;
169
170		if ((map->a_name = malloc(name_len)) == NULL) {
171			free(map);
172			return (NULL);
173		}
174
175		strlcpy(map->a_name, name, name_len);
176		map->hrIndex = next_storage_index++;
177
178		STAILQ_INSERT_TAIL(&storage_map, map, link);
179
180		HRDBG("%s added into hrStorageMap at index=%d",
181		    name, map->hrIndex);
182	} else {
183		HRDBG("%s exists in hrStorageMap index=%d\n",
184		    name, map->hrIndex);
185	}
186
187	if ((entry = malloc(sizeof(*entry))) == NULL) {
188		syslog(LOG_WARNING, "%s: %m", __func__);
189		return (NULL);
190	}
191        memset(entry, 0, sizeof(*entry));
192
193	entry->index = map->hrIndex;
194
195	if ((entry->descr = strdup(map->a_name)) == NULL) {
196		free(entry);
197		return (NULL);
198	}
199
200	map->entry = entry;
201
202	INSERT_OBJECT_INT(entry, &storage_tbl);
203
204	return (entry);
205}
206
207/**
208 * Delete an entry from the storage table.
209 */
210static void
211storage_entry_delete(struct storage_entry *entry)
212{
213	struct storage_map_entry *map;
214
215	assert(entry != NULL);
216
217	TAILQ_REMOVE(&storage_tbl, entry, link);
218	STAILQ_FOREACH(map, &storage_map, link)
219		if (map->entry == entry) {
220			map->entry = NULL;
221			break;
222		}
223	free(entry->descr);
224	free(entry);
225}
226
227/**
228 * Find a table entry by its name.
229 */
230static struct storage_entry *
231storage_find_by_name(const char *name)
232{
233	struct storage_entry *entry;
234
235	TAILQ_FOREACH(entry, &storage_tbl, link)
236		if (strcmp(entry->descr, name) == 0)
237			return (entry);
238
239	return (NULL);
240}
241
242/*
243 * VM info.
244 */
245static void
246storage_OS_get_vm(void)
247{
248	int mib[2] = { CTL_VM, VM_TOTAL };
249	size_t len = sizeof(mem_stats);
250	int page_size_bytes;
251	struct storage_entry *entry;
252
253	if (sysctl(mib, 2, &mem_stats, &len, NULL, 0) < 0) {
254		syslog(LOG_ERR,
255		    "hrStoragetable: %s: sysctl({CTL_VM, VM_METER}) "
256		    "failed: %m", __func__);
257		assert(0);
258		return;
259	}
260
261	page_size_bytes = getpagesize();
262
263	/* Real Memory Metrics */
264	if ((entry = storage_find_by_name("Real Memory Metrics")) == NULL &&
265	    (entry = storage_entry_create("Real Memory Metrics")) == NULL)
266		return; /* I'm out of luck now, maybe next time */
267
268	entry->flags |= HR_STORAGE_FOUND;
269	entry->type = &OIDX_hrStorageRam_c;
270	entry->allocationUnits = page_size_bytes;
271	entry->size = mem_stats.t_rm;
272	entry->used = mem_stats.t_arm; /* ACTIVE is not USED - FIXME */
273	entry->allocationFailures = 0;
274
275	/* Shared Real Memory Metrics */
276	if ((entry = storage_find_by_name("Shared Real Memory Metrics")) ==
277	    NULL &&
278	    (entry = storage_entry_create("Shared Real Memory Metrics")) ==
279	    NULL)
280		return;
281
282	entry->flags |= HR_STORAGE_FOUND;
283	entry->type = &OIDX_hrStorageRam_c;
284	entry->allocationUnits = page_size_bytes;
285	entry->size = mem_stats.t_rmshr;
286	/* ACTIVE is not USED - FIXME */
287	entry->used = mem_stats.t_armshr;
288	entry->allocationFailures = 0;
289}
290
291static void
292storage_OS_get_memstat(void)
293{
294	struct memory_type *mt_item;
295	struct storage_entry *entry;
296
297	if (mt_list == NULL) {
298		if ((mt_list = memstat_mtl_alloc()) == NULL)
299			/* again? we have a serious problem */
300		return;
301	}
302
303	if (memstat_sysctl_all(mt_list, 0) < 0) {
304		syslog(LOG_ERR, "memstat_sysctl_all failed: %s",
305		    memstat_strerror(memstat_mtl_geterror(mt_list)) );
306		return;
307	}
308
309	if ((mt_item = memstat_mtl_first(mt_list)) == NULL) {
310		/* usually this is not an error, no errno for this failure*/
311		HRDBG("memstat_mtl_first failed");
312		return;
313	}
314
315	do {
316		const char *memstat_name;
317		uint64_t tmp_size;
318		int allocator;
319		char alloc_descr[SE_DESC_MLEN];
320
321		memstat_name = memstat_get_name(mt_item);
322
323		if (memstat_name == NULL || strlen(memstat_name) == 0)
324			continue;
325
326		switch (allocator = memstat_get_allocator(mt_item)) {
327
328		  case ALLOCATOR_MALLOC:
329			snprintf(alloc_descr, sizeof(alloc_descr),
330			    "MALLOC: %s", memstat_name);
331			break;
332
333		  case ALLOCATOR_UMA:
334			snprintf(alloc_descr, sizeof(alloc_descr),
335			    "UMA: %s", memstat_name);
336			break;
337
338		  default:
339			snprintf(alloc_descr, sizeof(alloc_descr),
340			    "UNKNOWN%d: %s", allocator, memstat_name);
341			break;
342		}
343
344		if ((entry = storage_find_by_name(alloc_descr)) == NULL &&
345		    (entry = storage_entry_create(alloc_descr)) == NULL)
346			return;
347
348		entry->flags |= HR_STORAGE_FOUND;
349		entry->type = &OIDX_hrStorageRam_c;
350
351		if ((tmp_size = memstat_get_size(mt_item)) == 0)
352			tmp_size = memstat_get_sizemask(mt_item);
353		entry->allocationUnits =
354		    (tmp_size  > INT_MAX ? INT_MAX : (int32_t)tmp_size);
355
356		tmp_size  = memstat_get_countlimit(mt_item);
357		entry->size =
358		    (tmp_size  > INT_MAX ? INT_MAX : (int32_t)tmp_size);
359
360		tmp_size = memstat_get_count(mt_item);
361		entry->used =
362		    (tmp_size  > INT_MAX ? INT_MAX : (int32_t)tmp_size);
363
364		tmp_size = memstat_get_failures(mt_item);
365		entry->allocationFailures =
366		    (tmp_size  > INT_MAX ? INT_MAX : (int32_t)tmp_size);
367
368	} while((mt_item = memstat_mtl_next(mt_item)) != NULL);
369}
370
371/**
372 * Get swap info
373 */
374static void
375storage_OS_get_swap(void)
376{
377        int nswapdev = 0;
378	size_t len = sizeof(nswapdev);
379	struct storage_entry *entry;
380	char swap_w_prefix[SE_DESC_MLEN];
381
382	if (sysctlbyname("vm.nswapdev", &nswapdev, &len, NULL,0 ) < 0) {
383		syslog(LOG_ERR,
384		    "hrStorageTable: sysctlbyname(\"vm.nswapdev\") "
385		    "failed. %m");
386		assert(0);
387		return;
388	}
389
390	if (nswapdev <= 0) {
391		HRDBG("vm.nswapdev is %d", nswapdev);
392		return;
393	}
394
395	if (nswapdev + 1 != (int)swap_devs_len || swap_devs == NULL) {
396		swap_devs_len = nswapdev + 1;
397		swap_devs = reallocf(swap_devs,
398		    swap_devs_len * sizeof(struct kvm_swap));
399
400		assert(swap_devs != NULL);
401		if (swap_devs == NULL) {
402			swap_devs_len = 0;
403			return;
404		}
405	}
406
407	nswapdev = kvm_getswapinfo(hr_kd, swap_devs, swap_devs_len, 0);
408	if (nswapdev < 0) {
409		syslog(LOG_ERR,
410		    "hrStorageTable: kvm_getswapinfo failed. %m\n");
411		assert(0);
412		return;
413	}
414
415	for (len = 0; len < (size_t)nswapdev; len++) {
416		memset(&swap_w_prefix[0], '\0', sizeof(swap_w_prefix));
417		snprintf(swap_w_prefix, sizeof(swap_w_prefix) - 1,
418		    "Swap:%s%s", _PATH_DEV, swap_devs[len].ksw_devname);
419
420		entry = storage_find_by_name(swap_w_prefix);
421		if (entry == NULL)
422			entry = storage_entry_create(swap_w_prefix);
423
424		assert (entry != NULL);
425		if (entry == NULL)
426			return; /* Out of luck */
427
428		entry->flags |= HR_STORAGE_FOUND;
429		entry->type = &OIDX_hrStorageVirtualMemory_c;
430		entry->allocationUnits = getpagesize();
431		entry->size = swap_devs[len].ksw_total;
432		entry->used = swap_devs[len].ksw_used;
433		entry->allocationFailures = 0;
434	}
435}
436
437/**
438 * Query the underlaying OS for the mounted file systems
439 * anf fill in the respective lists (for hrStorageTable and for hrFSTable)
440 */
441static void
442storage_OS_get_fs(void)
443{
444	struct storage_entry *entry;
445	uint64_t size, used;
446	int i, mounted_fs_count, units;
447	char fs_string[SE_DESC_MLEN];
448
449	if ((mounted_fs_count = getfsstat(NULL, 0, MNT_NOWAIT)) < 0) {
450		syslog(LOG_ERR, "hrStorageTable: getfsstat() failed: %m");
451		return; /* out of luck this time */
452	}
453
454	if (mounted_fs_count != (int)fs_buf_count || fs_buf == NULL) {
455		fs_buf_count = mounted_fs_count;
456		fs_buf = reallocf(fs_buf, fs_buf_count * sizeof(struct statfs));
457		if (fs_buf == NULL) {
458			fs_buf_count = 0;
459			assert(0);
460			return;
461		}
462	}
463
464	if ((mounted_fs_count = getfsstat(fs_buf,
465	    fs_buf_count * sizeof(struct statfs), MNT_NOWAIT)) < 0) {
466		syslog(LOG_ERR, "hrStorageTable: getfsstat() failed: %m");
467		return; /* out of luck this time */
468	}
469
470	HRDBG("got %d mounted FS", mounted_fs_count);
471
472	fs_tbl_pre_refresh();
473
474	for (i = 0; i < mounted_fs_count; i++) {
475		snprintf(fs_string, sizeof(fs_string),
476		    "%s, type: %s, dev: %s", fs_buf[i].f_mntonname,
477		    fs_buf[i].f_fstypename, fs_buf[i].f_mntfromname);
478
479		entry = storage_find_by_name(fs_string);
480		if (entry == NULL)
481			entry = storage_entry_create(fs_string);
482
483		assert (entry != NULL);
484		if (entry == NULL)
485			return; /* Out of luck */
486
487		entry->flags |= HR_STORAGE_FOUND;
488		entry->type = fs_get_type(&fs_buf[i]); /*XXX - This is wrong*/
489
490		units = fs_buf[i].f_bsize;
491		size = fs_buf[i].f_blocks;
492		used = fs_buf[i].f_blocks - fs_buf[i].f_bfree;
493		while (size > INT_MAX) {
494			units <<= 1;
495			size >>= 1;
496			used >>= 1;
497		}
498		entry->allocationUnits = units;
499		entry->size = size;
500		entry->used = used;
501
502		entry->allocationFailures = 0;
503
504		/* take care of hrFSTable */
505		fs_tbl_process_statfs_entry(&fs_buf[i], entry->index);
506	}
507
508	fs_tbl_post_refresh();
509}
510
511/**
512 * Initialize storage table and populate it.
513 */
514void
515init_storage_tbl(void)
516{
517	if ((mt_list = memstat_mtl_alloc()) == NULL)
518		syslog(LOG_ERR,
519		    "hrStorageTable: memstat_mtl_alloc() failed: %m");
520
521	refresh_storage_tbl(1);
522}
523
524void
525fini_storage_tbl(void)
526{
527	struct storage_map_entry *n1;
528
529	if (swap_devs != NULL) {
530		free(swap_devs);
531		swap_devs = NULL;
532	}
533	swap_devs_len = 0;
534
535	if (fs_buf != NULL) {
536		free(fs_buf);
537		fs_buf = NULL;
538	}
539	fs_buf_count = 0;
540
541	while ((n1 = STAILQ_FIRST(&storage_map)) != NULL) {
542		STAILQ_REMOVE_HEAD(&storage_map, link);
543		if (n1->entry != NULL) {
544			TAILQ_REMOVE(&storage_tbl, n1->entry, link);
545			free(n1->entry->descr);
546			free(n1->entry);
547		}
548		free(n1->a_name);
549		free(n1);
550	}
551	assert(TAILQ_EMPTY(&storage_tbl));
552}
553
554void
555refresh_storage_tbl(int force)
556{
557	struct storage_entry *entry, *entry_tmp;
558
559	if (!force && storage_tick != 0 &&
560	    this_tick - storage_tick < storage_tbl_refresh) {
561		HRDBG("no refresh needed");
562		return;
563	}
564
565	/* mark each entry as missing */
566	TAILQ_FOREACH(entry, &storage_tbl, link)
567		entry->flags &= ~HR_STORAGE_FOUND;
568
569	storage_OS_get_vm();
570	storage_OS_get_swap();
571	storage_OS_get_fs();
572	storage_OS_get_memstat();
573
574	/*
575	 * Purge items that disappeared
576	 */
577	TAILQ_FOREACH_SAFE(entry, &storage_tbl, link, entry_tmp)
578		if (!(entry->flags & HR_STORAGE_FOUND))
579			storage_entry_delete(entry);
580
581	storage_tick = this_tick;
582
583	HRDBG("refresh DONE");
584}
585
586/*
587 * This is the implementation for a generated (by our SNMP tool)
588 * function prototype, see hostres_tree.h
589 * It handles the SNMP operations for hrStorageTable
590 */
591int
592op_hrStorageTable(struct snmp_context *ctx __unused, struct snmp_value *value,
593    u_int sub, u_int iidx __unused, enum snmp_op curr_op)
594{
595	struct storage_entry *entry;
596
597	refresh_storage_tbl(0);
598
599	switch (curr_op) {
600
601	case SNMP_OP_GETNEXT:
602		if ((entry = NEXT_OBJECT_INT(&storage_tbl,
603		    &value->var, sub)) == NULL)
604			return (SNMP_ERR_NOSUCHNAME);
605
606		value->var.len = sub + 1;
607		value->var.subs[sub] = entry->index;
608		goto get;
609
610	case SNMP_OP_GET:
611		if ((entry = FIND_OBJECT_INT(&storage_tbl,
612		    &value->var, sub)) == NULL)
613			return (SNMP_ERR_NOSUCHNAME);
614		goto get;
615
616	case SNMP_OP_SET:
617		if ((entry = FIND_OBJECT_INT(&storage_tbl,
618		    &value->var, sub)) == NULL)
619			return (SNMP_ERR_NO_CREATION);
620		return (SNMP_ERR_NOT_WRITEABLE);
621
622	case SNMP_OP_ROLLBACK:
623	case SNMP_OP_COMMIT:
624		abort();
625	}
626	abort();
627
628  get:
629	switch (value->var.subs[sub - 1]) {
630
631	case LEAF_hrStorageIndex:
632		value->v.integer = entry->index;
633		return (SNMP_ERR_NOERROR);
634
635	case LEAF_hrStorageType:
636		assert(entry->type != NULL);
637		value->v.oid = *entry->type;
638		return (SNMP_ERR_NOERROR);
639
640	case LEAF_hrStorageDescr:
641		assert(entry->descr != NULL);
642		return (string_get(value, entry->descr, -1));
643		break;
644
645	case LEAF_hrStorageAllocationUnits:
646		value->v.integer = entry->allocationUnits;
647		return (SNMP_ERR_NOERROR);
648
649	case LEAF_hrStorageSize:
650		value->v.integer = entry->size;
651		return (SNMP_ERR_NOERROR);
652
653	case LEAF_hrStorageUsed:
654		value->v.integer = entry->used;
655		return (SNMP_ERR_NOERROR);
656
657	case LEAF_hrStorageAllocationFailures:
658		value->v.uint32 = entry->allocationFailures;
659		return (SNMP_ERR_NOERROR);
660	}
661	abort();
662}
663