xref: /illumos-gate/usr/src/cmd/fm/fmd/common/fmd_ckpt.c (revision 1743a90d)
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 <sys/types.h>
28 #include <sys/mkdev.h>
29 #include <sys/stat.h>
30 
31 #include <strings.h>
32 #include <unistd.h>
33 #include <limits.h>
34 #include <fcntl.h>
35 
36 #include <fmd_module.h>
37 #include <fmd_error.h>
38 #include <fmd_alloc.h>
39 #include <fmd_case.h>
40 #include <fmd_serd.h>
41 #include <fmd_subr.h>
42 #include <fmd_conf.h>
43 #include <fmd_event.h>
44 #include <fmd_log.h>
45 #include <fmd_api.h>
46 #include <fmd_ckpt.h>
47 
48 #include <fmd.h>
49 
50 #define	P2ROUNDUP(x, align)	(-(-(x) & -(align)))
51 #define	IS_P2ALIGNED(v, a)	((((uintptr_t)(v)) & ((uintptr_t)(a) - 1)) == 0)
52 
53 /*
54  * The fmd_ckpt_t structure is used to manage all of the state needed by the
55  * various subroutines that save and restore checkpoints.  The structure is
56  * initialized using fmd_ckpt_create() or fmd_ckpt_open() and is destroyed
57  * by fmd_ckpt_destroy().  Refer to the subroutines below for more details.
58  */
59 typedef struct fmd_ckpt {
60 	char ckp_src[PATH_MAX];	/* ckpt input or output filename */
61 	char ckp_dst[PATH_MAX];	/* ckpt rename filename */
62 	uchar_t *ckp_buf;	/* data buffer base address */
63 	fcf_hdr_t *ckp_hdr;	/* file header pointer */
64 	uchar_t *ckp_ptr;	/* data buffer pointer */
65 	size_t ckp_size;	/* data buffer size */
66 	fcf_sec_t *ckp_secp;	/* section header table pointer */
67 	fcf_sec_t *ckp_modp;	/* section header for module */
68 	uint_t ckp_secs;	/* number of sections */
69 	char *ckp_strs;		/* string table base pointer */
70 	char *ckp_strp;		/* string table pointer */
71 	size_t ckp_strn;	/* string table size */
72 	int ckp_fd;		/* output descriptor */
73 	fmd_module_t *ckp_mp;	/* checkpoint module */
74 	void *ckp_arg;		/* private arg for callbacks */
75 } fmd_ckpt_t;
76 
77 typedef struct fmd_ckpt_desc {
78 	uint64_t secd_size;	/* minimum section size */
79 	uint32_t secd_entsize;	/* minimum section entry size */
80 	uint32_t secd_align;	/* section alignment */
81 } fmd_ckpt_desc_t;
82 
83 /*
84  * Table of FCF section descriptions.  Here we record the minimum size for each
85  * section (for use during restore) and the expected entry size and alignment
86  * for each section (for use during both checkpoint and restore).
87  */
88 static const fmd_ckpt_desc_t _fmd_ckpt_sections[] = {
89 { 0, 0, sizeof (uint8_t) },					   /* NONE */
90 { 1, 0, sizeof (char) },					   /* STRTAB */
91 { sizeof (fcf_module_t), 0, sizeof (uint32_t) },		   /* MODULE */
92 { sizeof (fcf_case_t), 0, sizeof (uint32_t) },			   /* CASE */
93 { sizeof (fcf_buf_t), sizeof (fcf_buf_t), sizeof (uint32_t) },	   /* BUFS */
94 { 0, 0, _MAX_ALIGNMENT },					   /* BUFFER */
95 { sizeof (fcf_serd_t), sizeof (fcf_serd_t), sizeof (uint64_t) },   /* SERD */
96 { sizeof (fcf_event_t), sizeof (fcf_event_t), sizeof (uint64_t) }, /* EVENTS */
97 { sizeof (fcf_nvl_t), sizeof (fcf_nvl_t), sizeof (uint64_t) },	   /* NVLISTS */
98 };
99 
100 static int
fmd_ckpt_create(fmd_ckpt_t * ckp,fmd_module_t * mp)101 fmd_ckpt_create(fmd_ckpt_t *ckp, fmd_module_t *mp)
102 {
103 	const char *dir = mp->mod_ckpt;
104 	const char *name = mp->mod_name;
105 	mode_t mode;
106 
107 	bzero(ckp, sizeof (fmd_ckpt_t));
108 	ckp->ckp_mp = mp;
109 
110 	ckp->ckp_size = sizeof (fcf_hdr_t);
111 	ckp->ckp_strn = 1; /* for \0 */
112 
113 	(void) snprintf(ckp->ckp_src, PATH_MAX, "%s/%s+", dir, name);
114 	(void) snprintf(ckp->ckp_dst, PATH_MAX, "%s/%s", dir, name);
115 
116 	(void) unlink(ckp->ckp_src);
117 	(void) fmd_conf_getprop(fmd.d_conf, "ckpt.mode", &mode);
118 	ckp->ckp_fd = open64(ckp->ckp_src, O_WRONLY | O_CREAT | O_EXCL, mode);
119 
120 	return (ckp->ckp_fd);
121 }
122 
123 /*PRINTFLIKE2*/
124 static int
fmd_ckpt_inval(fmd_ckpt_t * ckp,const char * format,...)125 fmd_ckpt_inval(fmd_ckpt_t *ckp, const char *format, ...)
126 {
127 	va_list ap;
128 
129 	va_start(ap, format);
130 	fmd_verror(EFMD_CKPT_INVAL, format, ap);
131 	va_end(ap);
132 
133 	fmd_free(ckp->ckp_buf, ckp->ckp_size);
134 	return (fmd_set_errno(EFMD_CKPT_INVAL));
135 }
136 
137 static int
fmd_ckpt_open(fmd_ckpt_t * ckp,fmd_module_t * mp)138 fmd_ckpt_open(fmd_ckpt_t *ckp, fmd_module_t *mp)
139 {
140 	struct stat64 st;
141 	uint64_t seclen;
142 	uint_t i;
143 	int err;
144 
145 	bzero(ckp, sizeof (fmd_ckpt_t));
146 	ckp->ckp_mp = mp;
147 
148 	(void) snprintf(ckp->ckp_src, PATH_MAX, "%s/%s",
149 	    mp->mod_ckpt, mp->mod_name);
150 
151 	if ((ckp->ckp_fd = open(ckp->ckp_src, O_RDONLY)) == -1)
152 		return (-1); /* failed to open checkpoint file */
153 
154 	if (fstat64(ckp->ckp_fd, &st) == -1) {
155 		err = errno;
156 		(void) close(ckp->ckp_fd);
157 		return (fmd_set_errno(err));
158 	}
159 
160 	ckp->ckp_buf = fmd_alloc(st.st_size, FMD_SLEEP);
161 	ckp->ckp_hdr = (void *)ckp->ckp_buf;
162 	ckp->ckp_size = read(ckp->ckp_fd, ckp->ckp_buf, st.st_size);
163 
164 	if (ckp->ckp_size != st.st_size || ckp->ckp_size < sizeof (fcf_hdr_t) ||
165 	    ckp->ckp_size != ckp->ckp_hdr->fcfh_filesz) {
166 		err = ckp->ckp_size == (size_t)-1L ? errno : EFMD_CKPT_SHORT;
167 		fmd_free(ckp->ckp_buf, st.st_size);
168 		(void) close(ckp->ckp_fd);
169 		return (fmd_set_errno(err));
170 	}
171 
172 	(void) close(ckp->ckp_fd);
173 	ckp->ckp_fd = -1;
174 
175 	/*
176 	 * Once we've read in a consistent copy of the FCF file and we're sure
177 	 * the header can be accessed, go through it and make sure everything
178 	 * is valid.  We also check that unused bits are zero so we can expand
179 	 * to use them safely in the future and support old files if needed.
180 	 */
181 	if (bcmp(&ckp->ckp_hdr->fcfh_ident[FCF_ID_MAG0],
182 	    FCF_MAG_STRING, FCF_MAG_STRLEN) != 0)
183 		return (fmd_ckpt_inval(ckp, "bad checkpoint magic string\n"));
184 
185 	if (ckp->ckp_hdr->fcfh_ident[FCF_ID_MODEL] != FCF_MODEL_NATIVE)
186 		return (fmd_ckpt_inval(ckp, "bad checkpoint data model\n"));
187 
188 	if (ckp->ckp_hdr->fcfh_ident[FCF_ID_ENCODING] != FCF_ENCODE_NATIVE)
189 		return (fmd_ckpt_inval(ckp, "bad checkpoint data encoding\n"));
190 
191 	if (ckp->ckp_hdr->fcfh_ident[FCF_ID_VERSION] != FCF_VERSION_1) {
192 		return (fmd_ckpt_inval(ckp, "bad checkpoint version %u\n",
193 		    ckp->ckp_hdr->fcfh_ident[FCF_ID_VERSION]));
194 	}
195 
196 	for (i = FCF_ID_PAD; i < FCF_ID_SIZE; i++) {
197 		if (ckp->ckp_hdr->fcfh_ident[i] != 0) {
198 			return (fmd_ckpt_inval(ckp,
199 			    "bad checkpoint padding at id[%d]", i));
200 		}
201 	}
202 
203 	if (ckp->ckp_hdr->fcfh_flags & ~FCF_FL_VALID)
204 		return (fmd_ckpt_inval(ckp, "bad checkpoint flags\n"));
205 
206 	if (ckp->ckp_hdr->fcfh_pad != 0)
207 		return (fmd_ckpt_inval(ckp, "reserved field in use\n"));
208 
209 	if (ckp->ckp_hdr->fcfh_hdrsize < sizeof (fcf_hdr_t) ||
210 	    ckp->ckp_hdr->fcfh_secsize < sizeof (fcf_sec_t)) {
211 		return (fmd_ckpt_inval(ckp,
212 		    "bad header and/or section size\n"));
213 	}
214 
215 	seclen = (uint64_t)ckp->ckp_hdr->fcfh_secnum *
216 	    (uint64_t)ckp->ckp_hdr->fcfh_secsize;
217 
218 	if (ckp->ckp_hdr->fcfh_secoff > ckp->ckp_size ||
219 	    seclen > ckp->ckp_size ||
220 	    ckp->ckp_hdr->fcfh_secoff + seclen > ckp->ckp_size ||
221 	    ckp->ckp_hdr->fcfh_secoff + seclen < ckp->ckp_hdr->fcfh_secoff)
222 		return (fmd_ckpt_inval(ckp, "truncated section headers\n"));
223 
224 	if (!IS_P2ALIGNED(ckp->ckp_hdr->fcfh_secoff, sizeof (uint64_t)) ||
225 	    !IS_P2ALIGNED(ckp->ckp_hdr->fcfh_secsize, sizeof (uint64_t)))
226 		return (fmd_ckpt_inval(ckp, "misaligned section headers\n"));
227 
228 	/*
229 	 * Once the header is validated, iterate over the section headers
230 	 * ensuring that each one is valid w.r.t. offset, alignment, and size.
231 	 * We also pick up the string table pointer during this pass.
232 	 */
233 	ckp->ckp_secp = (void *)(ckp->ckp_buf + ckp->ckp_hdr->fcfh_secoff);
234 	ckp->ckp_secs = ckp->ckp_hdr->fcfh_secnum;
235 
236 	for (i = 0; i < ckp->ckp_secs; i++) {
237 		fcf_sec_t *sp = (void *)(ckp->ckp_buf +
238 		    ckp->ckp_hdr->fcfh_secoff + ckp->ckp_hdr->fcfh_secsize * i);
239 
240 		const fmd_ckpt_desc_t *dp = &_fmd_ckpt_sections[sp->fcfs_type];
241 
242 		if (sp->fcfs_flags != 0) {
243 			return (fmd_ckpt_inval(ckp, "section %u has invalid "
244 			    "section flags (0x%x)\n", i, sp->fcfs_flags));
245 		}
246 
247 		if (sp->fcfs_align & (sp->fcfs_align - 1)) {
248 			return (fmd_ckpt_inval(ckp, "section %u has invalid "
249 			    "alignment (%u)\n", i, sp->fcfs_align));
250 		}
251 
252 		if (sp->fcfs_offset & (sp->fcfs_align - 1)) {
253 			return (fmd_ckpt_inval(ckp, "section %u is not properly"
254 			    " aligned (offset %llu)\n", i, sp->fcfs_offset));
255 		}
256 
257 		if (sp->fcfs_entsize != 0 &&
258 		    (sp->fcfs_entsize & (sp->fcfs_align - 1)) != 0) {
259 			return (fmd_ckpt_inval(ckp, "section %u has misaligned "
260 			    "entsize %u\n", i, sp->fcfs_entsize));
261 		}
262 
263 		if (sp->fcfs_offset > ckp->ckp_size ||
264 		    sp->fcfs_size > ckp->ckp_size ||
265 		    sp->fcfs_offset + sp->fcfs_size > ckp->ckp_size ||
266 		    sp->fcfs_offset + sp->fcfs_size < sp->fcfs_offset) {
267 			return (fmd_ckpt_inval(ckp, "section %u has corrupt "
268 			    "size or offset\n", i));
269 		}
270 
271 		if (sp->fcfs_type >= sizeof (_fmd_ckpt_sections) /
272 		    sizeof (_fmd_ckpt_sections[0])) {
273 			return (fmd_ckpt_inval(ckp, "section %u has unknown "
274 			    "section type %u\n", i, sp->fcfs_type));
275 		}
276 
277 		if (sp->fcfs_align != dp->secd_align) {
278 			return (fmd_ckpt_inval(ckp, "section %u has align %u "
279 			    "(not %u)\n", i, sp->fcfs_align, dp->secd_align));
280 		}
281 
282 		if (sp->fcfs_size < dp->secd_size ||
283 		    sp->fcfs_entsize < dp->secd_entsize) {
284 			return (fmd_ckpt_inval(ckp, "section %u has short "
285 			    "size or entsize\n", i));
286 		}
287 
288 		switch (sp->fcfs_type) {
289 		case FCF_SECT_STRTAB:
290 			if (ckp->ckp_strs != NULL) {
291 				return (fmd_ckpt_inval(ckp, "multiple string "
292 				    "tables are present in checkpoint file\n"));
293 			}
294 
295 			ckp->ckp_strs = (char *)ckp->ckp_buf + sp->fcfs_offset;
296 			ckp->ckp_strn = sp->fcfs_size;
297 
298 			if (ckp->ckp_strs[ckp->ckp_strn - 1] != '\0') {
299 				return (fmd_ckpt_inval(ckp, "string table %u "
300 				    "is missing terminating nul byte\n", i));
301 			}
302 			break;
303 
304 		case FCF_SECT_MODULE:
305 			if (ckp->ckp_modp != NULL) {
306 				return (fmd_ckpt_inval(ckp, "multiple module "
307 				    "sects are present in checkpoint file\n"));
308 			}
309 			ckp->ckp_modp = sp;
310 			break;
311 		}
312 	}
313 
314 	/*
315 	 * Ensure that the first section is an empty one of type FCF_SECT_NONE.
316 	 * This is done to ensure that links can use index 0 as a null section.
317 	 */
318 	if (ckp->ckp_secs == 0 || ckp->ckp_secp->fcfs_type != FCF_SECT_NONE ||
319 	    ckp->ckp_secp->fcfs_entsize != 0 || ckp->ckp_secp->fcfs_size != 0) {
320 		return (fmd_ckpt_inval(ckp, "section 0 is not of the "
321 		    "appropriate size and/or attributes (SECT_NONE)\n"));
322 	}
323 
324 	if (ckp->ckp_modp == NULL) {
325 		return (fmd_ckpt_inval(ckp,
326 		    "no module section found in file\n"));
327 	}
328 
329 	return (0);
330 }
331 
332 static void
fmd_ckpt_destroy(fmd_ckpt_t * ckp)333 fmd_ckpt_destroy(fmd_ckpt_t *ckp)
334 {
335 	if (ckp->ckp_buf != NULL)
336 		fmd_free(ckp->ckp_buf, ckp->ckp_size);
337 	if (ckp->ckp_fd >= 0)
338 		(void) close(ckp->ckp_fd);
339 }
340 
341 /*
342  * fmd_ckpt_error() is used as a wrapper around fmd_error() for ckpt routines.
343  * It calls fmd_module_unlock() on behalf of its caller, logs the error, and
344  * then aborts the API call and the surrounding module entry point by doing an
345  * fmd_module_abort(), which longjmps to the place where we entered the module.
346  * Depending on the type of error and conf settings, we will reset or fail.
347  */
348 /*PRINTFLIKE3*/
349 static void
fmd_ckpt_error(fmd_ckpt_t * ckp,int err,const char * format,...)350 fmd_ckpt_error(fmd_ckpt_t *ckp, int err, const char *format, ...)
351 {
352 	fmd_module_t *mp = ckp->ckp_mp;
353 	va_list ap;
354 
355 	va_start(ap, format);
356 	fmd_verror(err, format, ap);
357 	va_end(ap);
358 
359 	if (fmd_module_locked(mp))
360 		fmd_module_unlock(mp);
361 
362 	fmd_ckpt_destroy(ckp);
363 	fmd_module_abort(mp, err);
364 }
365 
366 static fcf_secidx_t
fmd_ckpt_section(fmd_ckpt_t * ckp,const void * data,uint_t type,uint64_t size)367 fmd_ckpt_section(fmd_ckpt_t *ckp, const void *data, uint_t type, uint64_t size)
368 {
369 	const fmd_ckpt_desc_t *dp;
370 
371 	ASSERT(type < sizeof (_fmd_ckpt_sections) / sizeof (fmd_ckpt_desc_t));
372 	dp = &_fmd_ckpt_sections[type];
373 
374 	ckp->ckp_ptr = (uchar_t *)
375 	    P2ROUNDUP((uintptr_t)ckp->ckp_ptr, dp->secd_align);
376 
377 	ckp->ckp_secp->fcfs_type = type;
378 	ckp->ckp_secp->fcfs_align = dp->secd_align;
379 	ckp->ckp_secp->fcfs_flags = 0;
380 	ckp->ckp_secp->fcfs_entsize = dp->secd_entsize;
381 	ckp->ckp_secp->fcfs_offset = (size_t)(ckp->ckp_ptr - ckp->ckp_buf);
382 	ckp->ckp_secp->fcfs_size = size;
383 
384 	/*
385 	 * If the data pointer is non-NULL, copy the data to our buffer; else
386 	 * the caller is responsible for doing so and updating ckp->ckp_ptr.
387 	 */
388 	if (data != NULL) {
389 		bcopy(data, ckp->ckp_ptr, size);
390 		ckp->ckp_ptr += size;
391 	}
392 
393 	ckp->ckp_secp++;
394 	return (ckp->ckp_secs++);
395 }
396 
397 static fcf_stridx_t
fmd_ckpt_string(fmd_ckpt_t * ckp,const char * s)398 fmd_ckpt_string(fmd_ckpt_t *ckp, const char *s)
399 {
400 	fcf_stridx_t idx = (fcf_stridx_t)(ckp->ckp_strp - ckp->ckp_strs);
401 
402 	(void) strcpy(ckp->ckp_strp, s);
403 	ckp->ckp_strp += strlen(s) + 1;
404 
405 	return (idx);
406 }
407 
408 static int
fmd_ckpt_alloc(fmd_ckpt_t * ckp,uint64_t gen)409 fmd_ckpt_alloc(fmd_ckpt_t *ckp, uint64_t gen)
410 {
411 	/*
412 	 * We've added up all the sections by now: add two more for SECT_NONE
413 	 * and SECT_STRTAB, and add the size of the section header table and
414 	 * string table to the total size.  We know that the fcf_hdr_t is
415 	 * aligned so that that fcf_sec_t's can follow it, and that fcf_sec_t
416 	 * is aligned so that any section can follow it, so no extra padding
417 	 * bytes need to be allocated between any of these items.
418 	 */
419 	ckp->ckp_secs += 2; /* for FCF_SECT_NONE and FCF_SECT_STRTAB */
420 	ckp->ckp_size += sizeof (fcf_sec_t) * ckp->ckp_secs;
421 	ckp->ckp_size += ckp->ckp_strn;
422 
423 	TRACE((FMD_DBG_CKPT, "alloc fcf buf size %u", ckp->ckp_size));
424 	ckp->ckp_buf = fmd_zalloc(ckp->ckp_size, FMD_NOSLEEP);
425 
426 	if (ckp->ckp_buf == NULL)
427 		return (-1); /* errno is set for us */
428 
429 	ckp->ckp_hdr = (void *)ckp->ckp_buf;
430 
431 	ckp->ckp_hdr->fcfh_ident[FCF_ID_MAG0] = FCF_MAG_MAG0;
432 	ckp->ckp_hdr->fcfh_ident[FCF_ID_MAG1] = FCF_MAG_MAG1;
433 	ckp->ckp_hdr->fcfh_ident[FCF_ID_MAG2] = FCF_MAG_MAG2;
434 	ckp->ckp_hdr->fcfh_ident[FCF_ID_MAG3] = FCF_MAG_MAG3;
435 	ckp->ckp_hdr->fcfh_ident[FCF_ID_MODEL] = FCF_MODEL_NATIVE;
436 	ckp->ckp_hdr->fcfh_ident[FCF_ID_ENCODING] = FCF_ENCODE_NATIVE;
437 	ckp->ckp_hdr->fcfh_ident[FCF_ID_VERSION] = FCF_VERSION;
438 
439 	ckp->ckp_hdr->fcfh_hdrsize = sizeof (fcf_hdr_t);
440 	ckp->ckp_hdr->fcfh_secsize = sizeof (fcf_sec_t);
441 	ckp->ckp_hdr->fcfh_secnum = ckp->ckp_secs;
442 	ckp->ckp_hdr->fcfh_secoff = sizeof (fcf_hdr_t);
443 	ckp->ckp_hdr->fcfh_filesz = ckp->ckp_size;
444 	ckp->ckp_hdr->fcfh_cgen = gen;
445 
446 	ckp->ckp_secs = 0; /* reset section counter for second pass */
447 	ckp->ckp_secp = (void *)(ckp->ckp_buf + sizeof (fcf_hdr_t));
448 	ckp->ckp_strs = (char *)ckp->ckp_buf + ckp->ckp_size - ckp->ckp_strn;
449 	ckp->ckp_strp = ckp->ckp_strs + 1; /* use first byte as \0 */
450 	ckp->ckp_ptr = (uchar_t *)(ckp->ckp_secp + ckp->ckp_hdr->fcfh_secnum);
451 
452 	(void) fmd_ckpt_section(ckp, NULL, FCF_SECT_NONE, 0);
453 	return (0);
454 }
455 
456 static int
fmd_ckpt_commit(fmd_ckpt_t * ckp)457 fmd_ckpt_commit(fmd_ckpt_t *ckp)
458 {
459 	fcf_sec_t *secbase = (void *)(ckp->ckp_buf + sizeof (fcf_hdr_t));
460 	size_t stroff = ckp->ckp_size - ckp->ckp_strn;
461 
462 	/*
463 	 * Before committing the checkpoint, we assert that fmd_ckpt_t's sizes
464 	 * and current pointer locations all add up appropriately.  Any ASSERTs
465 	 * which trip here likely indicate an inconsistency in the code for the
466 	 * reservation pass and the buffer update pass of the FCF subroutines.
467 	 */
468 	ASSERT((size_t)(ckp->ckp_ptr - ckp->ckp_buf) == stroff);
469 	(void) fmd_ckpt_section(ckp, NULL, FCF_SECT_STRTAB, ckp->ckp_strn);
470 	ckp->ckp_ptr += ckp->ckp_strn; /* string table is already filled in */
471 
472 	ASSERT(ckp->ckp_secs == ckp->ckp_hdr->fcfh_secnum);
473 	ASSERT(ckp->ckp_secp == secbase + ckp->ckp_hdr->fcfh_secnum);
474 	ASSERT(ckp->ckp_ptr == ckp->ckp_buf + ckp->ckp_hdr->fcfh_filesz);
475 
476 	if (write(ckp->ckp_fd, ckp->ckp_buf, ckp->ckp_size) != ckp->ckp_size ||
477 	    fsync(ckp->ckp_fd) != 0 || close(ckp->ckp_fd) != 0)
478 		return (-1); /* errno is set for us */
479 
480 	ckp->ckp_fd = -1; /* fd is now closed */
481 	return (rename(ckp->ckp_src, ckp->ckp_dst) != 0);
482 }
483 
484 static void
fmd_ckpt_resv(fmd_ckpt_t * ckp,size_t size,size_t align)485 fmd_ckpt_resv(fmd_ckpt_t *ckp, size_t size, size_t align)
486 {
487 	if (size != 0) {
488 		ckp->ckp_size = P2ROUNDUP(ckp->ckp_size, align) + size;
489 		ckp->ckp_secs++;
490 	}
491 }
492 
493 static void
fmd_ckpt_resv_buf(fmd_buf_t * bp,fmd_ckpt_t * ckp)494 fmd_ckpt_resv_buf(fmd_buf_t *bp, fmd_ckpt_t *ckp)
495 {
496 	ckp->ckp_size = P2ROUNDUP(ckp->ckp_size, _MAX_ALIGNMENT) + bp->buf_size;
497 	ckp->ckp_strn += strlen(bp->buf_name) + 1;
498 	ckp->ckp_secs++;
499 }
500 
501 static void
fmd_ckpt_save_buf(fmd_buf_t * bp,fmd_ckpt_t * ckp)502 fmd_ckpt_save_buf(fmd_buf_t *bp, fmd_ckpt_t *ckp)
503 {
504 	fcf_buf_t *fcfb = ckp->ckp_arg;
505 
506 	fcfb->fcfb_name = fmd_ckpt_string(ckp, bp->buf_name);
507 	fcfb->fcfb_data = fmd_ckpt_section(ckp,
508 	    bp->buf_data, FCF_SECT_BUFFER, bp->buf_size);
509 
510 	ckp->ckp_arg = fcfb + 1;
511 }
512 
513 static void
fmd_ckpt_save_event(fmd_ckpt_t * ckp,fmd_event_t * e)514 fmd_ckpt_save_event(fmd_ckpt_t *ckp, fmd_event_t *e)
515 {
516 	fcf_event_t *fcfe = (void *)ckp->ckp_ptr;
517 	fmd_event_impl_t *ep = (fmd_event_impl_t *)e;
518 	fmd_log_t *lp = ep->ev_log;
519 
520 	fcfe->fcfe_todsec = ep->ev_time.ftv_sec;
521 	fcfe->fcfe_todnsec = ep->ev_time.ftv_nsec;
522 	fcfe->fcfe_major = lp ? major(lp->log_stat.st_dev) : -1U;
523 	fcfe->fcfe_minor = lp ? minor(lp->log_stat.st_dev) : -1U;
524 	fcfe->fcfe_inode = lp ? lp->log_stat.st_ino : -1ULL;
525 	fcfe->fcfe_offset = ep->ev_off;
526 
527 	ckp->ckp_ptr += sizeof (fcf_event_t);
528 }
529 
530 static void
fmd_ckpt_save_nvlist(fmd_ckpt_t * ckp,nvlist_t * nvl)531 fmd_ckpt_save_nvlist(fmd_ckpt_t *ckp, nvlist_t *nvl)
532 {
533 	fcf_nvl_t *fcfn = (void *)ckp->ckp_ptr;
534 	char *nvbuf = (char *)ckp->ckp_ptr + sizeof (fcf_nvl_t);
535 	size_t nvsize = 0;
536 
537 	(void) nvlist_size(nvl, &nvsize, NV_ENCODE_NATIVE);
538 	fcfn->fcfn_size = (uint64_t)nvsize;
539 
540 	(void) nvlist_pack(nvl, &nvbuf, &nvsize, NV_ENCODE_NATIVE, 0);
541 	ckp->ckp_ptr += sizeof (fcf_nvl_t) + nvsize;
542 
543 	ckp->ckp_ptr = (uchar_t *)
544 	    P2ROUNDUP((uintptr_t)ckp->ckp_ptr, sizeof (uint64_t));
545 }
546 
547 static void
fmd_ckpt_resv_serd(fmd_serd_eng_t * sgp,fmd_ckpt_t * ckp)548 fmd_ckpt_resv_serd(fmd_serd_eng_t *sgp, fmd_ckpt_t *ckp)
549 {
550 	fmd_ckpt_resv(ckp,
551 	    sizeof (fcf_event_t) * sgp->sg_count, sizeof (uint64_t));
552 
553 	ckp->ckp_strn += strlen(sgp->sg_name) + 1;
554 }
555 
556 static void
fmd_ckpt_save_serd(fmd_serd_eng_t * sgp,fmd_ckpt_t * ckp)557 fmd_ckpt_save_serd(fmd_serd_eng_t *sgp, fmd_ckpt_t *ckp)
558 {
559 	fcf_serd_t *fcfd = ckp->ckp_arg;
560 	fcf_secidx_t evsec = FCF_SECT_NONE;
561 	fmd_serd_elem_t *sep;
562 
563 	if (sgp->sg_count != 0) {
564 		evsec = fmd_ckpt_section(ckp, NULL, FCF_SECT_EVENTS,
565 		    sizeof (fcf_event_t) * sgp->sg_count);
566 
567 		for (sep = fmd_list_next(&sgp->sg_list);
568 		    sep != NULL; sep = fmd_list_next(sep))
569 			fmd_ckpt_save_event(ckp, sep->se_event);
570 	}
571 
572 	fcfd->fcfd_name = fmd_ckpt_string(ckp, sgp->sg_name);
573 	fcfd->fcfd_events = evsec;
574 	fcfd->fcfd_pad = 0;
575 	fcfd->fcfd_n = sgp->sg_n;
576 	fcfd->fcfd_t = sgp->sg_t;
577 
578 	ckp->ckp_arg = fcfd + 1;
579 }
580 
581 static void
fmd_ckpt_resv_case(fmd_ckpt_t * ckp,fmd_case_t * cp)582 fmd_ckpt_resv_case(fmd_ckpt_t *ckp, fmd_case_t *cp)
583 {
584 	fmd_case_impl_t *cip = (fmd_case_impl_t *)cp;
585 	fmd_case_susp_t *cis;
586 	uint_t n;
587 
588 	if (cip->ci_xprt != NULL)
589 		return; /* do not checkpoint cases from remote transports */
590 
591 	n = fmd_buf_hash_count(&cip->ci_bufs);
592 	fmd_buf_hash_apply(&cip->ci_bufs, (fmd_buf_f *)fmd_ckpt_resv_buf, ckp);
593 	fmd_ckpt_resv(ckp, sizeof (fcf_buf_t) * n, sizeof (uint32_t));
594 
595 	if (cip->ci_principal != NULL)
596 		fmd_ckpt_resv(ckp, sizeof (fcf_event_t), sizeof (uint64_t));
597 
598 	fmd_ckpt_resv(ckp,
599 	    sizeof (fcf_event_t) * cip->ci_nitems, sizeof (uint64_t));
600 
601 	if (cip->ci_nsuspects != 0)
602 		ckp->ckp_size = P2ROUNDUP(ckp->ckp_size, sizeof (uint64_t));
603 
604 	cip->ci_nvsz = 0; /* compute size of packed suspect nvlist array */
605 
606 	for (cis = cip->ci_suspects; cis != NULL; cis = cis->cis_next) {
607 		size_t nvsize = 0;
608 
609 		(void) nvlist_size(cis->cis_nvl, &nvsize, NV_ENCODE_NATIVE);
610 		cip->ci_nvsz += sizeof (fcf_nvl_t) + nvsize;
611 		cip->ci_nvsz = P2ROUNDUP(cip->ci_nvsz, sizeof (uint64_t));
612 	}
613 
614 	fmd_ckpt_resv(ckp, cip->ci_nvsz, sizeof (uint64_t));
615 	fmd_ckpt_resv(ckp, sizeof (fcf_case_t), sizeof (uint32_t));
616 	ckp->ckp_strn += strlen(cip->ci_uuid) + 1;
617 }
618 
619 static void
fmd_ckpt_save_case(fmd_ckpt_t * ckp,fmd_case_t * cp)620 fmd_ckpt_save_case(fmd_ckpt_t *ckp, fmd_case_t *cp)
621 {
622 	fmd_case_impl_t *cip = (fmd_case_impl_t *)cp;
623 
624 	fmd_case_item_t *cit;
625 	fmd_case_susp_t *cis;
626 	fcf_case_t fcfc;
627 	uint_t n;
628 
629 	fcf_secidx_t bufsec = FCF_SECIDX_NONE;
630 	fcf_secidx_t evsec = FCF_SECIDX_NONE;
631 	fcf_secidx_t nvsec = FCF_SECIDX_NONE;
632 	fcf_secidx_t prsec = FCF_SECIDX_NONE;
633 
634 	if (cip->ci_xprt != NULL)
635 		return; /* do not checkpoint cases from remote transports */
636 
637 	if ((n = fmd_buf_hash_count(&cip->ci_bufs)) != 0) {
638 		size_t size = sizeof (fcf_buf_t) * n;
639 		fcf_buf_t *bufs = ckp->ckp_arg = fmd_alloc(size, FMD_SLEEP);
640 
641 		fmd_buf_hash_apply(&cip->ci_bufs,
642 		    (fmd_buf_f *)fmd_ckpt_save_buf, ckp);
643 
644 		bufsec = fmd_ckpt_section(ckp, bufs, FCF_SECT_BUFS, size);
645 		fmd_free(bufs, size);
646 	}
647 
648 	if (cip->ci_principal != NULL) {
649 		prsec = fmd_ckpt_section(ckp, NULL, FCF_SECT_EVENTS,
650 		    sizeof (fcf_event_t));
651 
652 		fmd_ckpt_save_event(ckp, cip->ci_principal);
653 	}
654 
655 	if (cip->ci_nitems != 0) {
656 		evsec = fmd_ckpt_section(ckp, NULL, FCF_SECT_EVENTS,
657 		    sizeof (fcf_event_t) * cip->ci_nitems);
658 
659 		for (cit = cip->ci_items; cit != NULL; cit = cit->cit_next)
660 			fmd_ckpt_save_event(ckp, cit->cit_event);
661 	}
662 
663 	if (cip->ci_nsuspects != 0) {
664 		nvsec = fmd_ckpt_section(ckp, NULL,
665 		    FCF_SECT_NVLISTS, cip->ci_nvsz);
666 
667 		for (cis = cip->ci_suspects; cis != NULL; cis = cis->cis_next)
668 			fmd_ckpt_save_nvlist(ckp, cis->cis_nvl);
669 	}
670 
671 	fcfc.fcfc_uuid = fmd_ckpt_string(ckp, cip->ci_uuid);
672 	fcfc.fcfc_bufs = bufsec;
673 	fcfc.fcfc_principal = prsec;
674 	fcfc.fcfc_events = evsec;
675 	fcfc.fcfc_suspects = nvsec;
676 
677 	switch (cip->ci_state) {
678 	case FMD_CASE_UNSOLVED:
679 		fcfc.fcfc_state = FCF_CASE_UNSOLVED;
680 		break;
681 	case FMD_CASE_SOLVED:
682 		fcfc.fcfc_state = FCF_CASE_SOLVED;
683 		break;
684 	case FMD_CASE_CLOSE_WAIT:
685 		fcfc.fcfc_state = FCF_CASE_CLOSE_WAIT;
686 		break;
687 	default:
688 		fmd_panic("case %p (%s) has invalid state %u",
689 		    (void *)cp, cip->ci_uuid, cip->ci_state);
690 	}
691 
692 	(void) fmd_ckpt_section(ckp, &fcfc, FCF_SECT_CASE, sizeof (fcf_case_t));
693 }
694 
695 static void
fmd_ckpt_resv_module(fmd_ckpt_t * ckp,fmd_module_t * mp)696 fmd_ckpt_resv_module(fmd_ckpt_t *ckp, fmd_module_t *mp)
697 {
698 	fmd_case_t *cp;
699 	uint_t n;
700 
701 	for (cp = fmd_list_next(&mp->mod_cases); cp; cp = fmd_list_next(cp))
702 		fmd_ckpt_resv_case(ckp, cp);
703 
704 	n = fmd_serd_hash_count(&mp->mod_serds);
705 	fmd_serd_hash_apply(&mp->mod_serds,
706 	    (fmd_serd_eng_f *)fmd_ckpt_resv_serd, ckp);
707 	fmd_ckpt_resv(ckp, sizeof (fcf_serd_t) * n, sizeof (uint64_t));
708 
709 	n = fmd_buf_hash_count(&mp->mod_bufs);
710 	fmd_buf_hash_apply(&mp->mod_bufs, (fmd_buf_f *)fmd_ckpt_resv_buf, ckp);
711 	fmd_ckpt_resv(ckp, sizeof (fcf_buf_t) * n, sizeof (uint32_t));
712 
713 	fmd_ckpt_resv(ckp, sizeof (fcf_module_t), sizeof (uint32_t));
714 	ckp->ckp_strn += strlen(mp->mod_name) + 1;
715 	ckp->ckp_strn += strlen(mp->mod_path) + 1;
716 	ckp->ckp_strn += strlen(mp->mod_info->fmdi_desc) + 1;
717 	ckp->ckp_strn += strlen(mp->mod_info->fmdi_vers) + 1;
718 }
719 
720 static void
fmd_ckpt_save_module(fmd_ckpt_t * ckp,fmd_module_t * mp)721 fmd_ckpt_save_module(fmd_ckpt_t *ckp, fmd_module_t *mp)
722 {
723 	fcf_secidx_t bufsec = FCF_SECIDX_NONE;
724 	fcf_module_t fcfm;
725 	fmd_case_t *cp;
726 	uint_t n;
727 
728 	for (cp = fmd_list_next(&mp->mod_cases); cp; cp = fmd_list_next(cp))
729 		fmd_ckpt_save_case(ckp, cp);
730 
731 	if ((n = fmd_serd_hash_count(&mp->mod_serds)) != 0) {
732 		size_t size = sizeof (fcf_serd_t) * n;
733 		fcf_serd_t *serds = ckp->ckp_arg = fmd_alloc(size, FMD_SLEEP);
734 
735 		fmd_serd_hash_apply(&mp->mod_serds,
736 		    (fmd_serd_eng_f *)fmd_ckpt_save_serd, ckp);
737 
738 		(void) fmd_ckpt_section(ckp, serds, FCF_SECT_SERD, size);
739 		fmd_free(serds, size);
740 	}
741 
742 	if ((n = fmd_buf_hash_count(&mp->mod_bufs)) != 0) {
743 		size_t size = sizeof (fcf_buf_t) * n;
744 		fcf_buf_t *bufs = ckp->ckp_arg = fmd_alloc(size, FMD_SLEEP);
745 
746 		fmd_buf_hash_apply(&mp->mod_bufs,
747 		    (fmd_buf_f *)fmd_ckpt_save_buf, ckp);
748 
749 		bufsec = fmd_ckpt_section(ckp, bufs, FCF_SECT_BUFS, size);
750 		fmd_free(bufs, size);
751 	}
752 
753 	fcfm.fcfm_name = fmd_ckpt_string(ckp, mp->mod_name);
754 	fcfm.fcfm_path = fmd_ckpt_string(ckp, mp->mod_path);
755 	fcfm.fcfm_desc = fmd_ckpt_string(ckp, mp->mod_info->fmdi_desc);
756 	fcfm.fcfm_vers = fmd_ckpt_string(ckp, mp->mod_info->fmdi_vers);
757 	fcfm.fcfm_bufs = bufsec;
758 
759 	(void) fmd_ckpt_section(ckp, &fcfm,
760 	    FCF_SECT_MODULE, sizeof (fcf_module_t));
761 }
762 
763 void
fmd_ckpt_save(fmd_module_t * mp)764 fmd_ckpt_save(fmd_module_t *mp)
765 {
766 	struct stat64 st;
767 	char path[PATH_MAX];
768 	mode_t dirmode;
769 
770 	hrtime_t now = gethrtime();
771 	fmd_ckpt_t ckp;
772 	int err;
773 
774 	ASSERT(fmd_module_locked(mp));
775 
776 	/*
777 	 * If checkpointing is disabled for the module, just return.  We must
778 	 * commit the module state anyway to transition pending log events.
779 	 */
780 	if (mp->mod_stats->ms_ckpt_save.fmds_value.bool == FMD_B_FALSE) {
781 		fmd_module_commit(mp);
782 		return;
783 	}
784 
785 	if (!(mp->mod_flags & (FMD_MOD_MDIRTY | FMD_MOD_CDIRTY)))
786 		return; /* no checkpoint is necessary for this module */
787 
788 	TRACE((FMD_DBG_CKPT, "ckpt save begin %s %llu",
789 	    mp->mod_name, mp->mod_gen + 1));
790 
791 	/*
792 	 * If the per-module checkpoint directory isn't found or isn't of type
793 	 * directory, move aside whatever is there (if anything) and attempt
794 	 * to mkdir(2) a new module checkpoint directory.  If this fails, we
795 	 * have no choice but to abort the checkpoint and try again later.
796 	 */
797 	if (stat64(mp->mod_ckpt, &st) != 0 || !S_ISDIR(st.st_mode)) {
798 		(void) snprintf(path, sizeof (path), "%s-", mp->mod_ckpt);
799 		(void) rename(mp->mod_ckpt, path);
800 		(void) fmd_conf_getprop(fmd.d_conf, "ckpt.dirmode", &dirmode);
801 
802 		if (mkdir(mp->mod_ckpt, dirmode) != 0) {
803 			fmd_error(EFMD_CKPT_MKDIR,
804 			    "failed to mkdir %s", mp->mod_ckpt);
805 			return; /* return without clearing dirty bits */
806 		}
807 	}
808 
809 	/*
810 	 * Create a temporary file to write out the checkpoint into, and create
811 	 * a fmd_ckpt_t structure to manage construction of the checkpoint.  We
812 	 * then figure out how much space will be required, and allocate it.
813 	 */
814 	if (fmd_ckpt_create(&ckp, mp) == -1) {
815 		fmd_error(EFMD_CKPT_CREATE, "failed to create %s", ckp.ckp_src);
816 		return;
817 	}
818 
819 	fmd_ckpt_resv_module(&ckp, mp);
820 
821 	if (fmd_ckpt_alloc(&ckp, mp->mod_gen + 1) != 0) {
822 		fmd_error(EFMD_CKPT_NOMEM, "failed to build %s", ckp.ckp_src);
823 		fmd_ckpt_destroy(&ckp);
824 		return;
825 	}
826 
827 	/*
828 	 * Fill in the checkpoint content, write it to disk, sync it, and then
829 	 * atomically rename it to the destination path.  If this fails, we
830 	 * have no choice but to leave all our dirty bits set and return.
831 	 */
832 	fmd_ckpt_save_module(&ckp, mp);
833 	err = fmd_ckpt_commit(&ckp);
834 	fmd_ckpt_destroy(&ckp);
835 
836 	if (err != 0) {
837 		fmd_error(EFMD_CKPT_COMMIT, "failed to commit %s", ckp.ckp_dst);
838 		return; /* return without clearing dirty bits */
839 	}
840 
841 	fmd_module_commit(mp);
842 	TRACE((FMD_DBG_CKPT, "ckpt save end %s", mp->mod_name));
843 
844 	mp->mod_stats->ms_ckpt_cnt.fmds_value.ui64++;
845 	mp->mod_stats->ms_ckpt_time.fmds_value.ui64 += gethrtime() - now;
846 
847 	fmd_dprintf(FMD_DBG_CKPT, "saved checkpoint of %s (%llu)\n",
848 	    mp->mod_name, mp->mod_gen);
849 }
850 
851 /*
852  * Utility function to retrieve a pointer to a section's header and verify that
853  * it is of the expected type or it is a FCF_SECT_NONE reference.
854  */
855 static const fcf_sec_t *
fmd_ckpt_secptr(fmd_ckpt_t * ckp,fcf_secidx_t sid,uint_t type)856 fmd_ckpt_secptr(fmd_ckpt_t *ckp, fcf_secidx_t sid, uint_t type)
857 {
858 	const fcf_sec_t *sp = (void *)(ckp->ckp_buf +
859 	    ckp->ckp_hdr->fcfh_secoff + ckp->ckp_hdr->fcfh_secsize * sid);
860 
861 	return (sid < ckp->ckp_secs && (sp->fcfs_type == type ||
862 	    sp->fcfs_type == FCF_SECT_NONE) ? sp : NULL);
863 }
864 
865 /*
866  * Utility function to retrieve the data pointer for a particular section.  The
867  * validity of the header values has already been checked by fmd_ckpt_open().
868  */
869 static const void *
fmd_ckpt_dataptr(fmd_ckpt_t * ckp,const fcf_sec_t * sp)870 fmd_ckpt_dataptr(fmd_ckpt_t *ckp, const fcf_sec_t *sp)
871 {
872 	return (ckp->ckp_buf + sp->fcfs_offset);
873 }
874 
875 /*
876  * Utility function to retrieve the end of the data region for a particular
877  * section.  The validity of this value has been confirmed by fmd_ckpt_open().
878  */
879 static const void *
fmd_ckpt_datalim(fmd_ckpt_t * ckp,const fcf_sec_t * sp)880 fmd_ckpt_datalim(fmd_ckpt_t *ckp, const fcf_sec_t *sp)
881 {
882 	return (ckp->ckp_buf + sp->fcfs_offset + sp->fcfs_size);
883 }
884 
885 /*
886  * Utility function to retrieve a string pointer (fcf_stridx_t).  If the string
887  * index is valid, the string data is returned; otherwise 'defstr' is returned.
888  */
889 static const char *
fmd_ckpt_strptr(fmd_ckpt_t * ckp,fcf_stridx_t sid,const char * defstr)890 fmd_ckpt_strptr(fmd_ckpt_t *ckp, fcf_stridx_t sid, const char *defstr)
891 {
892 	return (sid < ckp->ckp_strn ? ckp->ckp_strs + sid : defstr);
893 }
894 
895 static void
fmd_ckpt_restore_events(fmd_ckpt_t * ckp,fcf_secidx_t sid,int (* func)(void *,fmd_event_t *),void * arg)896 fmd_ckpt_restore_events(fmd_ckpt_t *ckp, fcf_secidx_t sid,
897     int (*func)(void *, fmd_event_t *), void *arg)
898 {
899 	const fcf_event_t *fcfe;
900 	const fcf_sec_t *sp;
901 	fmd_timeval_t ftv;
902 	fmd_log_t *lp, *errlp;
903 	uint_t i, n;
904 	uint32_t e_maj, e_min;
905 	uint64_t e_ino;
906 
907 	if ((sp = fmd_ckpt_secptr(ckp, sid, FCF_SECT_EVENTS)) == NULL) {
908 		fmd_ckpt_error(ckp, EFMD_CKPT_INVAL,
909 		    "invalid link to section %u: expected events\n", sid);
910 	}
911 
912 	if (sp->fcfs_size == 0)
913 		return; /* empty events section or type none */
914 
915 	fcfe = fmd_ckpt_dataptr(ckp, sp);
916 	n = sp->fcfs_size / sp->fcfs_entsize;
917 
918 	/*
919 	 * Hold the reader lock on log pointers to block log rotation during
920 	 * the section restore so that we can safely insert refs to d_errlog.
921 	 */
922 	(void) pthread_rwlock_rdlock(&fmd.d_log_lock);
923 	errlp = fmd.d_errlog;
924 
925 	e_maj = major(errlp->log_stat.st_dev);
926 	e_min = minor(errlp->log_stat.st_dev);
927 	e_ino = errlp->log_stat.st_ino;
928 
929 	for (i = 0; i < n; i++) {
930 		fmd_event_t *ep;
931 
932 		ftv.ftv_sec = fcfe->fcfe_todsec;
933 		ftv.ftv_nsec = fcfe->fcfe_todnsec;
934 
935 		if (e_ino == fcfe->fcfe_inode &&
936 		    e_maj == fcfe->fcfe_major &&
937 		    e_min == fcfe->fcfe_minor)
938 			lp = errlp;
939 		else
940 			lp = NULL;
941 
942 		ep = fmd_event_recreate(FMD_EVT_PROTOCOL,
943 		    &ftv, NULL, NULL, lp, fcfe->fcfe_offset, 0);
944 		fmd_event_hold(ep);
945 		(void) func(arg, ep);
946 		fmd_event_rele(ep);
947 
948 		fcfe = (fcf_event_t *)((uintptr_t)fcfe + sp->fcfs_entsize);
949 	}
950 
951 	(void) pthread_rwlock_unlock(&fmd.d_log_lock);
952 }
953 
954 static int
fmd_ckpt_restore_suspects(fmd_ckpt_t * ckp,fmd_case_t * cp,fcf_secidx_t sid)955 fmd_ckpt_restore_suspects(fmd_ckpt_t *ckp, fmd_case_t *cp, fcf_secidx_t sid)
956 {
957 	const fcf_nvl_t *fcfn, *endn;
958 	const fcf_sec_t *sp;
959 	nvlist_t *nvl;
960 	int err, i;
961 
962 	if ((sp = fmd_ckpt_secptr(ckp, sid, FCF_SECT_NVLISTS)) == NULL) {
963 		fmd_ckpt_error(ckp, EFMD_CKPT_INVAL,
964 		    "invalid link to section %u: expected nvlists\n", sid);
965 	}
966 
967 	fcfn = fmd_ckpt_dataptr(ckp, sp);
968 	endn = fmd_ckpt_datalim(ckp, sp);
969 
970 	for (i = 0; fcfn < endn; i++) {
971 		char *data = (char *)fcfn + sp->fcfs_entsize;
972 		size_t size = (size_t)fcfn->fcfn_size;
973 
974 		if (fcfn->fcfn_size > (size_t)((char *)endn - data)) {
975 			fmd_ckpt_error(ckp, EFMD_CKPT_INVAL, "nvlist %u [%d] "
976 			    "size %u exceeds buffer\n", sid, i, size);
977 		}
978 
979 		if ((err = nvlist_xunpack(data, size, &nvl, &fmd.d_nva)) != 0) {
980 			fmd_ckpt_error(ckp, EFMD_CKPT_INVAL, "failed to "
981 			    "unpack nvlist %u [%d]: %s\n", sid, i,
982 			    fmd_strerror(err));
983 		}
984 
985 		fmd_case_insert_suspect(cp, nvl);
986 
987 		size = sp->fcfs_entsize + fcfn->fcfn_size;
988 		size = P2ROUNDUP(size, sizeof (uint64_t));
989 		fcfn = (fcf_nvl_t *)((uintptr_t)fcfn + size);
990 	}
991 
992 	return (i);
993 }
994 
995 static void
fmd_ckpt_restore_bufs(fmd_ckpt_t * ckp,fmd_module_t * mp,fmd_case_t * cp,fcf_secidx_t sid)996 fmd_ckpt_restore_bufs(fmd_ckpt_t *ckp, fmd_module_t *mp,
997     fmd_case_t *cp, fcf_secidx_t sid)
998 {
999 	const fcf_sec_t *sp, *dsp;
1000 	const fcf_buf_t *fcfb;
1001 	uint_t i, n;
1002 
1003 	if ((sp = fmd_ckpt_secptr(ckp, sid, FCF_SECT_BUFS)) == NULL) {
1004 		fmd_ckpt_error(ckp, EFMD_CKPT_INVAL,
1005 		    "invalid link to section %u: expected bufs\n", sid);
1006 	}
1007 
1008 	if (sp->fcfs_size == 0)
1009 		return; /* empty events section or type none */
1010 
1011 	fcfb = fmd_ckpt_dataptr(ckp, sp);
1012 	n = sp->fcfs_size / sp->fcfs_entsize;
1013 
1014 	for (i = 0; i < n; i++) {
1015 		dsp = fmd_ckpt_secptr(ckp, fcfb->fcfb_data, FCF_SECT_BUFFER);
1016 
1017 		if (dsp == NULL) {
1018 			fmd_ckpt_error(ckp, EFMD_CKPT_INVAL, "invalid %u "
1019 			    "buffer link %u\n", sid, fcfb->fcfb_data);
1020 		}
1021 
1022 		fmd_buf_write((fmd_hdl_t *)mp, cp,
1023 		    fmd_ckpt_strptr(ckp, fcfb->fcfb_name, "<CORRUPT>"),
1024 		    ckp->ckp_buf + dsp->fcfs_offset, dsp->fcfs_size);
1025 
1026 		fcfb = (fcf_buf_t *)((uintptr_t)fcfb + sp->fcfs_entsize);
1027 	}
1028 }
1029 
1030 static void
fmd_ckpt_restore_case(fmd_ckpt_t * ckp,fmd_module_t * mp,const fcf_sec_t * sp)1031 fmd_ckpt_restore_case(fmd_ckpt_t *ckp, fmd_module_t *mp, const fcf_sec_t *sp)
1032 {
1033 	const fcf_case_t *fcfc = fmd_ckpt_dataptr(ckp, sp);
1034 	const char *uuid = fmd_ckpt_strptr(ckp, fcfc->fcfc_uuid, NULL);
1035 	fmd_case_t *cp;
1036 	int n;
1037 
1038 	if (uuid == NULL || fcfc->fcfc_state > FCF_CASE_CLOSE_WAIT) {
1039 		fmd_ckpt_error(ckp, EFMD_CKPT_INVAL, "corrupt %u case uuid "
1040 		    "and/or state\n", (uint_t)(sp - ckp->ckp_secp));
1041 	}
1042 
1043 	fmd_module_lock(mp);
1044 
1045 	if ((cp = fmd_case_recreate(mp, NULL,
1046 	    fcfc->fcfc_state != FCF_CASE_UNSOLVED ? FCF_CASE_SOLVED :
1047 	    FMD_CASE_UNSOLVED, uuid, NULL)) == NULL) {
1048 		fmd_ckpt_error(ckp, EFMD_CKPT_INVAL,
1049 		    "duplicate case uuid: %s\n", uuid);
1050 	}
1051 
1052 	fmd_ckpt_restore_events(ckp, fcfc->fcfc_principal,
1053 	    fmd_case_insert_principal, cp);
1054 
1055 	fmd_ckpt_restore_events(ckp, fcfc->fcfc_events,
1056 	    fmd_case_insert_event, cp);
1057 
1058 	/*
1059 	 * Once solved, treat suspects from resource cache as master copy.
1060 	 *
1061 	 * If !fmd.d_running, this module must be a builtin, and so we don't
1062 	 * want to restore suspects or call fmd_case_transition_update() at this
1063 	 * stage. The suspects will be added later from the resource cache.
1064 	 * Calling fmd_case_transition("SOLVED") is OK here as the state is
1065 	 * already solved, so all it does is update the case flags.
1066 	 */
1067 	if (fmd.d_running && (n = ((fmd_case_impl_t *)cp)->ci_nsuspects) == 0)
1068 		n = fmd_ckpt_restore_suspects(ckp, cp, fcfc->fcfc_suspects);
1069 
1070 	if (!fmd.d_running)
1071 		fmd_case_transition(cp, FMD_CASE_SOLVED, FMD_CF_SOLVED);
1072 	else if (fcfc->fcfc_state == FCF_CASE_SOLVED)
1073 		fmd_case_transition_update(cp, FMD_CASE_SOLVED, FMD_CF_SOLVED);
1074 	else if (fcfc->fcfc_state == FCF_CASE_CLOSE_WAIT && n != 0)
1075 		fmd_case_transition(cp, FMD_CASE_CLOSE_WAIT, FMD_CF_SOLVED);
1076 	else if (fcfc->fcfc_state == FCF_CASE_CLOSE_WAIT && n == 0)
1077 		fmd_case_transition(cp, FMD_CASE_CLOSE_WAIT, 0);
1078 
1079 	fmd_module_unlock(mp);
1080 	fmd_ckpt_restore_bufs(ckp, mp, cp, fcfc->fcfc_bufs);
1081 }
1082 
1083 static void
fmd_ckpt_restore_serd(fmd_ckpt_t * ckp,fmd_module_t * mp,const fcf_sec_t * sp)1084 fmd_ckpt_restore_serd(fmd_ckpt_t *ckp, fmd_module_t *mp, const fcf_sec_t *sp)
1085 {
1086 	const fcf_serd_t *fcfd = fmd_ckpt_dataptr(ckp, sp);
1087 	uint_t i, n = sp->fcfs_size / sp->fcfs_entsize;
1088 	const fcf_sec_t *esp;
1089 	const char *s;
1090 
1091 	for (i = 0; i < n; i++) {
1092 		esp = fmd_ckpt_secptr(ckp, fcfd->fcfd_events, FCF_SECT_EVENTS);
1093 
1094 		if (esp == NULL) {
1095 			fmd_ckpt_error(ckp, EFMD_CKPT_INVAL,
1096 			    "invalid events link %u\n", fcfd->fcfd_events);
1097 		}
1098 
1099 		if ((s = fmd_ckpt_strptr(ckp, fcfd->fcfd_name, NULL)) == NULL) {
1100 			fmd_ckpt_error(ckp, EFMD_CKPT_INVAL,
1101 			    "serd name %u is corrupt\n", fcfd->fcfd_name);
1102 		}
1103 
1104 		fmd_serd_create((fmd_hdl_t *)mp, s, fcfd->fcfd_n, fcfd->fcfd_t);
1105 		fmd_module_lock(mp);
1106 
1107 		fmd_ckpt_restore_events(ckp, fcfd->fcfd_events,
1108 		    fmd_serd_eng_record,
1109 		    fmd_serd_eng_lookup(&mp->mod_serds, s));
1110 
1111 		fmd_module_unlock(mp);
1112 		fcfd = (fcf_serd_t *)((uintptr_t)fcfd + sp->fcfs_entsize);
1113 	}
1114 }
1115 
1116 static void
fmd_ckpt_restore_module(fmd_ckpt_t * ckp,fmd_module_t * mp)1117 fmd_ckpt_restore_module(fmd_ckpt_t *ckp, fmd_module_t *mp)
1118 {
1119 	const fcf_module_t *fcfm = fmd_ckpt_dataptr(ckp, ckp->ckp_modp);
1120 	const fcf_sec_t *sp;
1121 	uint_t i;
1122 
1123 	if (strcmp(mp->mod_name, fmd_ckpt_strptr(ckp, fcfm->fcfm_name, "")) ||
1124 	    strcmp(mp->mod_path, fmd_ckpt_strptr(ckp, fcfm->fcfm_path, ""))) {
1125 		fmd_ckpt_error(ckp, EFMD_CKPT_INVAL,
1126 		    "checkpoint is not for module %s\n", mp->mod_name);
1127 	}
1128 
1129 	for (i = 0; i < ckp->ckp_secs; i++) {
1130 		sp = (void *)(ckp->ckp_buf +
1131 		    ckp->ckp_hdr->fcfh_secoff + ckp->ckp_hdr->fcfh_secsize * i);
1132 
1133 		switch (sp->fcfs_type) {
1134 		case FCF_SECT_CASE:
1135 			fmd_ckpt_restore_case(ckp, mp, sp);
1136 			break;
1137 		case FCF_SECT_SERD:
1138 			fmd_ckpt_restore_serd(ckp, mp, sp);
1139 			break;
1140 		}
1141 	}
1142 
1143 	fmd_ckpt_restore_bufs(ckp, mp, NULL, fcfm->fcfm_bufs);
1144 	mp->mod_gen = ckp->ckp_hdr->fcfh_cgen;
1145 }
1146 
1147 /*
1148  * Restore a checkpoint for the specified module.  Any errors which occur
1149  * during restore will call fmd_ckpt_error() or trigger an fmd_api_error(),
1150  * either of which will automatically unlock the module and trigger an abort.
1151  */
1152 void
fmd_ckpt_restore(fmd_module_t * mp)1153 fmd_ckpt_restore(fmd_module_t *mp)
1154 {
1155 	fmd_ckpt_t ckp;
1156 
1157 	if (mp->mod_stats->ms_ckpt_restore.fmds_value.bool == FMD_B_FALSE)
1158 		return; /* never restore checkpoints for this module */
1159 
1160 	TRACE((FMD_DBG_CKPT, "ckpt restore begin %s", mp->mod_name));
1161 
1162 	if (fmd_ckpt_open(&ckp, mp) == -1) {
1163 		if (errno != ENOENT)
1164 			fmd_error(EFMD_CKPT_OPEN, "can't open %s", ckp.ckp_src);
1165 		TRACE((FMD_DBG_CKPT, "ckpt restore end %s", mp->mod_name));
1166 		return;
1167 	}
1168 
1169 	ASSERT(!fmd_module_locked(mp));
1170 	fmd_ckpt_restore_module(&ckp, mp);
1171 	fmd_ckpt_destroy(&ckp);
1172 	fmd_module_clrdirty(mp);
1173 
1174 	TRACE((FMD_DBG_CKPT, "ckpt restore end %s", mp->mod_name));
1175 	fmd_dprintf(FMD_DBG_CKPT, "restored checkpoint of %s\n", mp->mod_name);
1176 }
1177 
1178 /*
1179  * Delete the module's checkpoint file.  This is used by the ckpt.zero property
1180  * code or by the fmadm reset RPC service path to force a checkpoint delete.
1181  */
1182 void
fmd_ckpt_delete(fmd_module_t * mp)1183 fmd_ckpt_delete(fmd_module_t *mp)
1184 {
1185 	char path[PATH_MAX];
1186 
1187 	(void) snprintf(path, sizeof (path),
1188 	    "%s/%s", mp->mod_ckpt, mp->mod_name);
1189 
1190 	TRACE((FMD_DBG_CKPT, "delete %s ckpt", mp->mod_name));
1191 
1192 	if (unlink(path) != 0 && errno != ENOENT)
1193 		fmd_error(EFMD_CKPT_DELETE, "failed to delete %s", path);
1194 }
1195 
1196 /*
1197  * Move aside the module's checkpoint file if checkpoint restore has failed.
1198  * We rename the file rather than deleting it in the hopes that someone might
1199  * send it to us for post-mortem analysis of whether we have a checkpoint bug.
1200  */
1201 void
fmd_ckpt_rename(fmd_module_t * mp)1202 fmd_ckpt_rename(fmd_module_t *mp)
1203 {
1204 	char src[PATH_MAX], dst[PATH_MAX];
1205 
1206 	(void) snprintf(src, sizeof (src), "%s/%s", mp->mod_ckpt, mp->mod_name);
1207 	(void) snprintf(dst, sizeof (dst), "%s-", src);
1208 
1209 	TRACE((FMD_DBG_CKPT, "rename %s ckpt", mp->mod_name));
1210 
1211 	if (rename(src, dst) != 0 && errno != ENOENT)
1212 		fmd_error(EFMD_CKPT_DELETE, "failed to rename %s", src);
1213 }
1214