xref: /freebsd-src/sys/arm/arm/minidump_machdep.c (revision 2eb4d8dc723da3cf7d735a3226ae49da4c8c5dbc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2006 Peter Wemm
5  * Copyright (c) 2008 Semihalf, Grzegorz Bernacki
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  * from: FreeBSD: src/sys/i386/i386/minidump_machdep.c,v 1.6 2008/08/17 23:27:27
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_watchdog.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/conf.h>
40 #include <sys/cons.h>
41 #include <sys/kernel.h>
42 #include <sys/kerneldump.h>
43 #include <sys/msgbuf.h>
44 #ifdef SW_WATCHDOG
45 #include <sys/watchdog.h>
46 #endif
47 #include <vm/vm.h>
48 #include <vm/vm_param.h>
49 #include <vm/vm_page.h>
50 #include <vm/vm_phys.h>
51 #include <vm/vm_dumpset.h>
52 #include <vm/pmap.h>
53 #include <machine/atomic.h>
54 #include <machine/cpu.h>
55 #include <machine/elf.h>
56 #include <machine/md_var.h>
57 #include <machine/minidump.h>
58 
59 CTASSERT(sizeof(struct kerneldumpheader) == 512);
60 
61 static struct kerneldumpheader kdh;
62 
63 /* Handle chunked writes. */
64 static size_t fragsz;
65 static void *dump_va;
66 static uint64_t counter, progress;
67 
68 static int
69 is_dumpable(vm_paddr_t pa)
70 {
71 	vm_page_t m;
72 	int i;
73 
74 	if ((m = vm_phys_paddr_to_vm_page(pa)) != NULL)
75 		return ((m->flags & PG_NODUMP) == 0);
76 	for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) {
77 		if (pa >= dump_avail[i] && pa < dump_avail[i + 1])
78 			return (1);
79 	}
80 	return (0);
81 }
82 
83 #define PG2MB(pgs) (((pgs) + (1 << 8) - 1) >> 8)
84 
85 static int
86 blk_flush(struct dumperinfo *di)
87 {
88 	int error;
89 
90 	if (fragsz == 0)
91 		return (0);
92 
93 	error = dump_append(di, dump_va, 0, fragsz);
94 	fragsz = 0;
95 	return (error);
96 }
97 
98 static int
99 blk_write(struct dumperinfo *di, char *ptr, vm_paddr_t pa, size_t sz)
100 {
101 	size_t len;
102 	int error, i, c;
103 	u_int maxdumpsz;
104 
105 	maxdumpsz = min(di->maxiosize, MAXDUMPPGS * PAGE_SIZE);
106 	if (maxdumpsz == 0)	/* seatbelt */
107 		maxdumpsz = PAGE_SIZE;
108 	error = 0;
109 	if (ptr != NULL && pa != 0) {
110 		printf("cant have both va and pa!\n");
111 		return (EINVAL);
112 	}
113 	if (pa != 0) {
114 		if ((sz % PAGE_SIZE) != 0) {
115 			printf("size not page aligned\n");
116 			return (EINVAL);
117 		}
118 		if ((pa & PAGE_MASK) != 0) {
119 			printf("address not page aligned\n");
120 			return (EINVAL);
121 		}
122 	}
123 	if (ptr != NULL) {
124 		/* Flush any pre-existing pa pages before a virtual dump. */
125 		error = blk_flush(di);
126 		if (error)
127 			return (error);
128 	}
129 	while (sz) {
130 		len = maxdumpsz - fragsz;
131 		if (len > sz)
132 			len = sz;
133 		counter += len;
134 		progress -= len;
135 		if (counter >> 22) {
136 			printf(" %lld", PG2MB(progress >> PAGE_SHIFT));
137 			counter &= (1<<22) - 1;
138 		}
139 
140 #ifdef SW_WATCHDOG
141 		wdog_kern_pat(WD_LASTVAL);
142 #endif
143 		if (ptr) {
144 			error = dump_append(di, ptr, 0, len);
145 			if (error)
146 				return (error);
147 			ptr += len;
148 			sz -= len;
149 		} else {
150 			for (i = 0; i < len; i += PAGE_SIZE)
151 				dump_va = pmap_kenter_temporary(pa + i,
152 				    (i + fragsz) >> PAGE_SHIFT);
153 			fragsz += len;
154 			pa += len;
155 			sz -= len;
156 			if (fragsz == maxdumpsz) {
157 				error = blk_flush(di);
158 				if (error)
159 					return (error);
160 			}
161 		}
162 
163 		/* Check for user abort. */
164 		c = cncheckc();
165 		if (c == 0x03)
166 			return (ECANCELED);
167 		if (c != -1)
168 			printf(" (CTRL-C to abort) ");
169 	}
170 
171 	return (0);
172 }
173 
174 /* A buffer for general use. Its size must be one page at least. */
175 static char dumpbuf[PAGE_SIZE] __aligned(sizeof(uint64_t));
176 CTASSERT(sizeof(dumpbuf) % sizeof(pt2_entry_t) == 0);
177 
178 int
179 minidumpsys(struct dumperinfo *di)
180 {
181 	struct minidumphdr mdhdr;
182 	uint64_t dumpsize, *dump_avail_buf;
183 	uint32_t ptesize;
184 	uint32_t pa, prev_pa = 0, count = 0;
185 	vm_offset_t va;
186 	int error, i;
187 	char *addr;
188 
189 	/*
190 	 * Flush caches.  Note that in the SMP case this operates only on the
191 	 * current CPU's L1 cache.  Before we reach this point, code in either
192 	 * the system shutdown or kernel debugger has called stop_cpus() to stop
193 	 * all cores other than this one.  Part of the ARM handling of
194 	 * stop_cpus() is to call wbinv_all() on that core's local L1 cache.  So
195 	 * by time we get to here, all that remains is to flush the L1 for the
196 	 * current CPU, then the L2.
197 	 */
198 	dcache_wbinv_poc_all();
199 
200 	counter = 0;
201 	/* Walk page table pages, set bits in vm_page_dump */
202 	ptesize = 0;
203 	for (va = KERNBASE; va < kernel_vm_end; va += PAGE_SIZE) {
204 		pa = pmap_dump_kextract(va, NULL);
205 		if (pa != 0 && is_dumpable(pa))
206 			dump_add_page(pa);
207 		ptesize += sizeof(pt2_entry_t);
208 	}
209 
210 	/* Calculate dump size. */
211 	dumpsize = ptesize;
212 	dumpsize += round_page(msgbufp->msg_size);
213 	dumpsize += round_page(nitems(dump_avail) * sizeof(uint64_t));
214 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
215 	VM_PAGE_DUMP_FOREACH(pa) {
216 		/* Clear out undumpable pages now if needed */
217 		if (is_dumpable(pa))
218 			dumpsize += PAGE_SIZE;
219 		else
220 			dump_drop_page(pa);
221 	}
222 	dumpsize += PAGE_SIZE;
223 
224 	progress = dumpsize;
225 
226 	/* Initialize mdhdr */
227 	bzero(&mdhdr, sizeof(mdhdr));
228 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
229 	mdhdr.version = MINIDUMP_VERSION;
230 	mdhdr.msgbufsize = msgbufp->msg_size;
231 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
232 	mdhdr.ptesize = ptesize;
233 	mdhdr.kernbase = KERNBASE;
234 	mdhdr.arch = __ARM_ARCH;
235 	mdhdr.mmuformat = MINIDUMP_MMU_FORMAT_V6;
236 	mdhdr.dumpavailsize = round_page(nitems(dump_avail) * sizeof(uint64_t));
237 
238 	dump_init_header(di, &kdh, KERNELDUMPMAGIC, KERNELDUMP_ARM_VERSION,
239 	    dumpsize);
240 
241 	error = dump_start(di, &kdh);
242 	if (error != 0)
243 		goto fail;
244 
245 	printf("Physical memory: %u MB\n", ptoa((uintmax_t)physmem) / 1048576);
246 	printf("Dumping %llu MB:", (long long)dumpsize >> 20);
247 
248 	/* Dump my header */
249 	bzero(dumpbuf, sizeof(dumpbuf));
250 	bcopy(&mdhdr, dumpbuf, sizeof(mdhdr));
251 	error = blk_write(di, dumpbuf, 0, PAGE_SIZE);
252 	if (error)
253 		goto fail;
254 
255 	/* Dump msgbuf up front */
256 	error = blk_write(di, (char *)msgbufp->msg_ptr, 0,
257 	    round_page(msgbufp->msg_size));
258 	if (error)
259 		goto fail;
260 
261 	/* Dump dump_avail.  Make a copy using 64-bit physical addresses. */
262 	_Static_assert(nitems(dump_avail) * sizeof(uint64_t) <= sizeof(dumpbuf),
263 	    "Large dump_avail not handled");
264 	bzero(dumpbuf, sizeof(dumpbuf));
265 	dump_avail_buf = (uint64_t *)dumpbuf;
266 	for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) {
267 		dump_avail_buf[i] = dump_avail[i];
268 		dump_avail_buf[i + 1] = dump_avail[i + 1];
269 	}
270 	error = blk_write(di, dumpbuf, 0, PAGE_SIZE);
271 	if (error)
272 		goto fail;
273 
274 	/* Dump bitmap */
275 	error = blk_write(di, (char *)vm_page_dump, 0,
276 	    round_page(BITSET_SIZE(vm_page_dump_pages)));
277 	if (error)
278 		goto fail;
279 
280 	/* Dump kernel page table pages */
281 	addr = dumpbuf;
282 	for (va = KERNBASE; va < kernel_vm_end; va += PAGE_SIZE) {
283 		pmap_dump_kextract(va, (pt2_entry_t *)addr);
284 		addr += sizeof(pt2_entry_t);
285 		if (addr == dumpbuf + sizeof(dumpbuf)) {
286 			error = blk_write(di, dumpbuf, 0, sizeof(dumpbuf));
287 			if (error != 0)
288 				goto fail;
289 			addr = dumpbuf;
290 		}
291 	}
292 	if (addr != dumpbuf) {
293 		error = blk_write(di, dumpbuf, 0, addr - dumpbuf);
294 		if (error != 0)
295 			goto fail;
296 	}
297 
298 	/* Dump memory chunks */
299 	VM_PAGE_DUMP_FOREACH(pa) {
300 		if (!count) {
301 			prev_pa = pa;
302 			count++;
303 		} else {
304 			if (pa == (prev_pa + count * PAGE_SIZE))
305 				count++;
306 			else {
307 				error = blk_write(di, NULL, prev_pa,
308 				    count * PAGE_SIZE);
309 				if (error)
310 					goto fail;
311 				count = 1;
312 				prev_pa = pa;
313 			}
314 		}
315 	}
316 	if (count) {
317 		error = blk_write(di, NULL, prev_pa, count * PAGE_SIZE);
318 		if (error)
319 			goto fail;
320 		count = 0;
321 		prev_pa = 0;
322 	}
323 
324 	error = blk_flush(di);
325 	if (error)
326 		goto fail;
327 
328 	error = dump_finish(di, &kdh);
329 	if (error != 0)
330 		goto fail;
331 
332 	printf("\nDump complete\n");
333 	return (0);
334 
335 fail:
336 	if (error < 0)
337 		error = -error;
338 
339 	if (error == ECANCELED)
340 		printf("\nDump aborted\n");
341 	else if (error == E2BIG || error == ENOSPC) {
342 		printf("\nDump failed. Partition too small (about %lluMB were "
343 		    "needed this time).\n", (long long)dumpsize >> 20);
344 	} else
345 		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
346 	return (error);
347 }
348