minidump_machdep.c revision 331722 
1/*-
2 * Copyright (c) 2010 Oleksandr Tymoshenko <gonzo@freebsd.org>
3 * Copyright (c) 2008 Semihalf, Grzegorz Bernacki
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * from: FreeBSD: src/sys/arm/arm/minidump_machdep.c v214223
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: stable/11/sys/mips/mips/minidump_machdep.c 331722 2018-03-29 02:50:57Z eadler $");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/conf.h>
36#include <sys/cons.h>
37#include <sys/kernel.h>
38#include <sys/kerneldump.h>
39#include <sys/msgbuf.h>
40#include <sys/vmmeter.h>
41#include <vm/vm.h>
42#include <vm/pmap.h>
43#include <machine/atomic.h>
44#include <machine/elf.h>
45#include <machine/md_var.h>
46#include <machine/vmparam.h>
47#include <machine/minidump.h>
48#include <machine/cache.h>
49
50CTASSERT(sizeof(struct kerneldumpheader) == 512);
51
52/*
53 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
54 * is to protect us from metadata and to protect metadata from us.
55 */
56#define	SIZEOF_METADATA		(64*1024)
57
58uint32_t *vm_page_dump;
59int vm_page_dump_size;
60
61static struct kerneldumpheader kdh;
62static off_t dumplo;
63static off_t origdumplo;
64
65/* Handle chunked writes. */
66static uint64_t counter, progress;
67/* Just auxiliary bufffer */
68static char tmpbuffer[PAGE_SIZE];
69
70extern pd_entry_t *kernel_segmap;
71
72CTASSERT(sizeof(*vm_page_dump) == 4);
73
74static int
75is_dumpable(vm_paddr_t pa)
76{
77	int i;
78
79	for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) {
80		if (pa >= dump_avail[i] && pa < dump_avail[i + 1])
81			return (1);
82	}
83	return (0);
84}
85
86void
87dump_add_page(vm_paddr_t pa)
88{
89	int idx, bit;
90
91	pa >>= PAGE_SHIFT;
92	idx = pa >> 5;		/* 2^5 = 32 */
93	bit = pa & 31;
94	atomic_set_int(&vm_page_dump[idx], 1ul << bit);
95}
96
97void
98dump_drop_page(vm_paddr_t pa)
99{
100	int idx, bit;
101
102	pa >>= PAGE_SHIFT;
103	idx = pa >> 5;		/* 2^5 = 32 */
104	bit = pa & 31;
105	atomic_clear_int(&vm_page_dump[idx], 1ul << bit);
106}
107
108#define PG2MB(pgs) (((pgs) + (1 << 8) - 1) >> 8)
109
110static int
111write_buffer(struct dumperinfo *di, char *ptr, size_t sz)
112{
113	size_t len;
114	int error, c;
115	u_int maxdumpsz;
116
117	maxdumpsz = di->maxiosize;
118
119	if (maxdumpsz == 0)	/* seatbelt */
120		maxdumpsz = PAGE_SIZE;
121
122	error = 0;
123
124	while (sz) {
125		len = min(maxdumpsz, sz);
126		counter += len;
127		progress -= len;
128
129		if (counter >> 22) {
130			printf(" %jd", PG2MB(progress >> PAGE_SHIFT));
131			counter &= (1<<22) - 1;
132		}
133
134		if (ptr) {
135			error = dump_write(di, ptr, 0, dumplo, len);
136			if (error)
137				return (error);
138			dumplo += len;
139			ptr += len;
140			sz -= len;
141		} else {
142			panic("pa is not supported");
143		}
144
145		/* Check for user abort. */
146		c = cncheckc();
147		if (c == 0x03)
148			return (ECANCELED);
149		if (c != -1)
150			printf(" (CTRL-C to abort) ");
151	}
152
153	return (0);
154}
155
156int
157minidumpsys(struct dumperinfo *di)
158{
159	struct minidumphdr mdhdr;
160	uint64_t dumpsize;
161	uint32_t ptesize;
162	uint32_t bits;
163	vm_paddr_t pa;
164	vm_offset_t prev_pte = 0;
165	uint32_t count = 0;
166	vm_offset_t va;
167	pt_entry_t *pte;
168	int i, bit, error;
169	void *dump_va;
170
171	/* Flush cache */
172	mips_dcache_wbinv_all();
173
174	counter = 0;
175	/* Walk page table pages, set bits in vm_page_dump */
176	ptesize = 0;
177
178	for (va = VM_MIN_KERNEL_ADDRESS; va < kernel_vm_end; va += NBPDR) {
179		ptesize += PAGE_SIZE;
180		pte = pmap_pte(kernel_pmap, va);
181		KASSERT(pte != NULL, ("pte for %jx is NULL", (uintmax_t)va));
182		for (i = 0; i < NPTEPG; i++) {
183			if (pte_test(&pte[i], PTE_V)) {
184				pa = TLBLO_PTE_TO_PA(pte[i]);
185				if (is_dumpable(pa))
186					dump_add_page(pa);
187			}
188		}
189	}
190
191	/*
192	 * Now mark pages from 0 to phys_avail[0], that's where kernel
193	 * and pages allocated by pmap_steal reside
194	 */
195	for (pa = 0; pa < phys_avail[0]; pa += PAGE_SIZE) {
196		if (is_dumpable(pa))
197			dump_add_page(pa);
198	}
199
200	/* Calculate dump size. */
201	dumpsize = ptesize;
202	dumpsize += round_page(msgbufp->msg_size);
203	dumpsize += round_page(vm_page_dump_size);
204
205	for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
206		bits = vm_page_dump[i];
207		while (bits) {
208			bit = ffs(bits) - 1;
209			pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) +
210			    bit) * PAGE_SIZE;
211			/* Clear out undumpable pages now if needed */
212			if (is_dumpable(pa))
213				dumpsize += PAGE_SIZE;
214			else
215				dump_drop_page(pa);
216			bits &= ~(1ul << bit);
217		}
218	}
219
220	dumpsize += PAGE_SIZE;
221
222	/* Determine dump offset on device. */
223	if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
224		error = ENOSPC;
225		goto fail;
226	}
227
228	origdumplo = dumplo = di->mediaoffset + di->mediasize - dumpsize;
229	dumplo -= sizeof(kdh) * 2;
230	progress = dumpsize;
231
232	/* Initialize mdhdr */
233	bzero(&mdhdr, sizeof(mdhdr));
234	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
235	mdhdr.version = MINIDUMP_VERSION;
236	mdhdr.msgbufsize = msgbufp->msg_size;
237	mdhdr.bitmapsize = vm_page_dump_size;
238	mdhdr.ptesize = ptesize;
239	mdhdr.kernbase = VM_MIN_KERNEL_ADDRESS;
240
241	mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_MIPS_VERSION, dumpsize,
242	    di->blocksize);
243
244	printf("Physical memory: %ju MB\n",
245	    (uintmax_t)ptoa((uintmax_t)physmem) / 1048576);
246	printf("Dumping %llu MB:", (long long)dumpsize >> 20);
247
248	/* Dump leader */
249	error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
250	if (error)
251		goto fail;
252	dumplo += sizeof(kdh);
253
254	/* Dump my header */
255	bzero(tmpbuffer, sizeof(tmpbuffer));
256	bcopy(&mdhdr, tmpbuffer, sizeof(mdhdr));
257	error = write_buffer(di, tmpbuffer, PAGE_SIZE);
258	if (error)
259		goto fail;
260
261	/* Dump msgbuf up front */
262	error = write_buffer(di, (char *)msgbufp->msg_ptr,
263	    round_page(msgbufp->msg_size));
264	if (error)
265		goto fail;
266
267	/* Dump bitmap */
268	error = write_buffer(di, (char *)vm_page_dump,
269	    round_page(vm_page_dump_size));
270	if (error)
271		goto fail;
272
273	/* Dump kernel page table pages */
274	for (va = VM_MIN_KERNEL_ADDRESS; va < kernel_vm_end; va += NBPDR) {
275		pte = pmap_pte(kernel_pmap, va);
276		KASSERT(pte != NULL, ("pte for %jx is NULL", (uintmax_t)va));
277		if (!count) {
278			prev_pte = (vm_offset_t)pte;
279			count++;
280		}
281		else {
282			if ((vm_offset_t)pte == (prev_pte + count * PAGE_SIZE))
283				count++;
284			else {
285				error = write_buffer(di, (char*)prev_pte,
286				    count * PAGE_SIZE);
287				if (error)
288					goto fail;
289				count = 1;
290				prev_pte = (vm_offset_t)pte;
291			}
292		}
293	}
294
295	if (count) {
296		error = write_buffer(di, (char*)prev_pte, count * PAGE_SIZE);
297		if (error)
298			goto fail;
299		count = 0;
300		prev_pte = 0;
301	}
302
303	/* Dump memory chunks  page by page*/
304	for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
305		bits = vm_page_dump[i];
306		while (bits) {
307			bit = ffs(bits) - 1;
308			pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) +
309			    bit) * PAGE_SIZE;
310			dump_va = pmap_kenter_temporary(pa, 0);
311			error = write_buffer(di, dump_va, PAGE_SIZE);
312			if (error)
313				goto fail;
314			pmap_kenter_temporary_free(pa);
315			bits &= ~(1ul << bit);
316		}
317	}
318
319	/* Dump trailer */
320	error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
321	if (error)
322		goto fail;
323	dumplo += sizeof(kdh);
324
325	/* Signal completion, signoff and exit stage left. */
326	dump_write(di, NULL, 0, 0, 0);
327	printf("\nDump complete\n");
328	return (0);
329
330fail:
331	if (error < 0)
332		error = -error;
333
334	if (error == ECANCELED)
335		printf("\nDump aborted\n");
336	else if (error == ENOSPC)
337		printf("\nDump failed. Partition too small.\n");
338	else
339		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
340	return (error);
341}
342