minidump_machdep.c revision 196019 
1/*-
2 * Copyright (c) 2008 Semihalf, Grzegorz Bernacki
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * from: FreeBSD: src/sys/i386/i386/minidump_machdep.c,v 1.6 2008/08/17 23:27:27
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/sys/arm/arm/minidump_machdep.c 196019 2009-08-01 19:26:27Z rwatson $");
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/conf.h>
35#include <sys/cons.h>
36#include <sys/kernel.h>
37#include <sys/kerneldump.h>
38#include <sys/msgbuf.h>
39#include <vm/vm.h>
40#include <vm/pmap.h>
41#include <machine/pmap.h>
42#include <machine/atomic.h>
43#include <machine/elf.h>
44#include <machine/md_var.h>
45#include <machine/vmparam.h>
46#include <machine/minidump.h>
47#include <machine/cpufunc.h>
48
49CTASSERT(sizeof(struct kerneldumpheader) == 512);
50
51/*
52 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
53 * is to protect us from metadata and to protect metadata from us.
54 */
55#define	SIZEOF_METADATA		(64*1024)
56
57uint32_t *vm_page_dump;
58int vm_page_dump_size;
59
60static struct kerneldumpheader kdh;
61static off_t dumplo;
62
63/* Handle chunked writes. */
64static size_t fragsz, offset;
65static void *dump_va;
66static uint64_t counter, progress;
67
68CTASSERT(sizeof(*vm_page_dump) == 4);
69
70static int
71is_dumpable(vm_paddr_t pa)
72{
73	int i;
74
75	for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) {
76		if (pa >= dump_avail[i] && pa < dump_avail[i + 1])
77			return (1);
78	}
79	return (0);
80}
81
82#define PG2MB(pgs) (((pgs) + (1 << 8) - 1) >> 8)
83
84static int
85blk_flush(struct dumperinfo *di)
86{
87	int error;
88
89	if (fragsz == 0)
90		return (0);
91
92	error = dump_write(di, (char*)dump_va + offset, 0, dumplo, fragsz - offset);
93	dumplo += (fragsz - offset);
94	fragsz = 0;
95	offset = 0;
96	return (error);
97}
98
99static int
100blk_write(struct dumperinfo *di, char *ptr, vm_paddr_t pa, size_t sz)
101{
102	size_t len;
103	int error, i, c;
104	u_int maxdumpsz;
105
106	maxdumpsz = di->maxiosize;
107
108	if (maxdumpsz == 0)	/* seatbelt */
109		maxdumpsz = PAGE_SIZE;
110
111	error = 0;
112
113	if (ptr != NULL && pa != 0) {
114		printf("cant have both va and pa!\n");
115		return (EINVAL);
116	}
117
118	if (ptr != NULL) {
119		/* If we're doing a virtual dump, flush any pre-existing pa pages */
120		error = blk_flush(di);
121		if (error)
122			return (error);
123	}
124
125	while (sz) {
126		if (fragsz == 0) {
127			offset = pa & PAGE_MASK;
128			fragsz += offset;
129		}
130		len = maxdumpsz - fragsz;
131		if (len > sz)
132			len = sz;
133		counter += len;
134		progress -= len;
135
136		if (counter >> 22) {
137			printf(" %lld", PG2MB(progress >> PAGE_SHIFT));
138			counter &= (1<<22) - 1;
139		}
140
141		if (ptr) {
142			error = dump_write(di, ptr, 0, dumplo, len);
143			if (error)
144				return (error);
145			dumplo += len;
146			ptr += len;
147			sz -= len;
148		} else {
149			for (i = 0; i < len; i += PAGE_SIZE)
150				dump_va = pmap_kenter_temp(pa + i,
151				    (i + fragsz) >> PAGE_SHIFT);
152			fragsz += len;
153			pa += len;
154			sz -= len;
155			if (fragsz == maxdumpsz) {
156				error = blk_flush(di);
157				if (error)
158					return (error);
159			}
160		}
161
162		/* Check for user abort. */
163		c = cncheckc();
164		if (c == 0x03)
165			return (ECANCELED);
166		if (c != -1)
167			printf(" (CTRL-C to abort) ");
168	}
169
170	return (0);
171}
172
173static int
174blk_write_cont(struct dumperinfo *di, vm_paddr_t pa, size_t sz)
175{
176	int error;
177
178	error = blk_write(di, 0, pa, sz);
179	if (error)
180		return (error);
181
182	error = blk_flush(di);
183	if (error)
184		return (error);
185
186	return (0);
187}
188
189/* A fake page table page, to avoid having to handle both 4K and 2M pages */
190static pt_entry_t fakept[NPTEPG];
191
192void
193minidumpsys(struct dumperinfo *di)
194{
195	struct minidumphdr mdhdr;
196	uint64_t dumpsize;
197	uint32_t ptesize;
198	uint32_t bits;
199	uint32_t pa, prev_pa = 0, count = 0;
200	vm_offset_t va;
201	pd_entry_t *pdp;
202	pt_entry_t *pt, *ptp;
203	int i, k, bit, error;
204	char *addr;
205
206	/* Flush cache */
207	cpu_idcache_wbinv_all();
208	cpu_l2cache_wbinv_all();
209
210	counter = 0;
211	/* Walk page table pages, set bits in vm_page_dump */
212	ptesize = 0;
213	for (va = KERNBASE; va < kernel_vm_end; va += NBPDR) {
214		/*
215		 * We always write a page, even if it is zero. Each
216		 * page written corresponds to 2MB of space
217		 */
218		ptesize += L2_TABLE_SIZE_REAL;
219		pmap_get_pde_pte(pmap_kernel(), va, &pdp, &ptp);
220		if (pmap_pde_v(pdp) && pmap_pde_section(pdp)) {
221			/* This is a section mapping 1M page. */
222			pa = (*pdp & L1_S_ADDR_MASK) | (va & ~L1_S_ADDR_MASK);
223			for (k = 0; k < (L1_S_SIZE / PAGE_SIZE); k++) {
224				if (is_dumpable(pa))
225					dump_add_page(pa);
226				pa += PAGE_SIZE;
227			}
228			continue;
229		}
230		if (pmap_pde_v(pdp) && pmap_pde_page(pdp)) {
231			/* Set bit for each valid page in this 1MB block */
232			addr = pmap_kenter_temp(*pdp & L1_C_ADDR_MASK, 0);
233			pt = (pt_entry_t*)(addr +
234			    (((uint32_t)*pdp  & L1_C_ADDR_MASK) & PAGE_MASK));
235			for (k = 0; k < 256; k++) {
236				if ((pt[k] & L2_TYPE_MASK) == L2_TYPE_L) {
237					pa = (pt[k] & L2_L_FRAME) |
238					    (va & L2_L_OFFSET);
239					for (i = 0; i < 16; i++) {
240						if (is_dumpable(pa))
241							dump_add_page(pa);
242						k++;
243						pa += PAGE_SIZE;
244					}
245				} else if ((pt[k] & L2_TYPE_MASK) == L2_TYPE_S) {
246					pa = (pt[k] & L2_S_FRAME) |
247					    (va & L2_S_OFFSET);
248					if (is_dumpable(pa))
249						dump_add_page(pa);
250				}
251			}
252		} else {
253			/* Nothing, we're going to dump a null page */
254		}
255	}
256
257	/* Calculate dump size. */
258	dumpsize = ptesize;
259	dumpsize += round_page(msgbufp->msg_size);
260	dumpsize += round_page(vm_page_dump_size);
261
262	for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
263		bits = vm_page_dump[i];
264		while (bits) {
265			bit = ffs(bits) - 1;
266			pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) +
267			    bit) * PAGE_SIZE;
268			/* Clear out undumpable pages now if needed */
269			if (is_dumpable(pa))
270				dumpsize += PAGE_SIZE;
271			else
272				dump_drop_page(pa);
273			bits &= ~(1ul << bit);
274		}
275	}
276
277	dumpsize += PAGE_SIZE;
278
279	/* Determine dump offset on device. */
280	if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
281		error = ENOSPC;
282		goto fail;
283	}
284
285	dumplo = di->mediaoffset + di->mediasize - dumpsize;
286	dumplo -= sizeof(kdh) * 2;
287	progress = dumpsize;
288
289	/* Initialize mdhdr */
290	bzero(&mdhdr, sizeof(mdhdr));
291	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
292	mdhdr.version = MINIDUMP_VERSION;
293	mdhdr.msgbufsize = msgbufp->msg_size;
294	mdhdr.bitmapsize = vm_page_dump_size;
295	mdhdr.ptesize = ptesize;
296	mdhdr.kernbase = KERNBASE;
297
298	mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_ARM_VERSION, dumpsize,
299	    di->blocksize);
300
301	printf("Physical memory: %u MB\n", ptoa((uintmax_t)physmem) / 1048576);
302	printf("Dumping %llu MB:", (long long)dumpsize >> 20);
303
304	/* Dump leader */
305	error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
306	if (error)
307		goto fail;
308	dumplo += sizeof(kdh);
309
310	/* Dump my header */
311	bzero(&fakept, sizeof(fakept));
312	bcopy(&mdhdr, &fakept, sizeof(mdhdr));
313	error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE);
314	if (error)
315		goto fail;
316
317	/* Dump msgbuf up front */
318	error = blk_write(di, (char *)msgbufp->msg_ptr, 0, round_page(msgbufp->msg_size));
319	if (error)
320		goto fail;
321
322	/* Dump bitmap */
323	error = blk_write(di, (char *)vm_page_dump, 0,
324	    round_page(vm_page_dump_size));
325	if (error)
326		goto fail;
327
328	/* Dump kernel page table pages */
329	for (va = KERNBASE; va < kernel_vm_end; va += NBPDR) {
330		/* We always write a page, even if it is zero */
331		pmap_get_pde_pte(pmap_kernel(), va, &pdp, &ptp);
332
333		if (pmap_pde_v(pdp) && pmap_pde_section(pdp))  {
334			if (count) {
335				error = blk_write_cont(di, prev_pa,
336				    count * L2_TABLE_SIZE_REAL);
337				if (error)
338					goto fail;
339				count = 0;
340				prev_pa = 0;
341			}
342			/* This is a single 2M block. Generate a fake PTP */
343			pa = (*pdp & L1_S_ADDR_MASK) | (va & ~L1_S_ADDR_MASK);
344			for (k = 0; k < (L1_S_SIZE / PAGE_SIZE); k++) {
345				fakept[k] = L2_S_PROTO | (pa + (k * PAGE_SIZE)) |
346				    L2_S_PROT(PTE_KERNEL,
347				    VM_PROT_READ | VM_PROT_WRITE);
348			}
349			error = blk_write(di, (char *)&fakept, 0,
350			    L2_TABLE_SIZE_REAL);
351			if (error)
352				goto fail;
353			/* Flush, in case we reuse fakept in the same block */
354			error = blk_flush(di);
355			if (error)
356				goto fail;
357			continue;
358		}
359		if (pmap_pde_v(pdp) && pmap_pde_page(pdp)) {
360			pa = *pdp & L1_C_ADDR_MASK;
361			if (!count) {
362				prev_pa = pa;
363				count++;
364			}
365			else {
366				if (pa == (prev_pa + count * L2_TABLE_SIZE_REAL))
367					count++;
368				else {
369					error = blk_write_cont(di, prev_pa,
370					    count * L2_TABLE_SIZE_REAL);
371					if (error)
372						goto fail;
373					count = 1;
374					prev_pa = pa;
375				}
376			}
377		} else {
378			if (count) {
379				error = blk_write_cont(di, prev_pa,
380				    count * L2_TABLE_SIZE_REAL);
381				if (error)
382					goto fail;
383				count = 0;
384				prev_pa = 0;
385			}
386			bzero(fakept, sizeof(fakept));
387			error = blk_write(di, (char *)&fakept, 0,
388			    L2_TABLE_SIZE_REAL);
389			if (error)
390				goto fail;
391			/* Flush, in case we reuse fakept in the same block */
392			error = blk_flush(di);
393			if (error)
394				goto fail;
395		}
396	}
397
398	if (count) {
399		error = blk_write_cont(di, prev_pa, count * L2_TABLE_SIZE_REAL);
400		if (error)
401			goto fail;
402		count = 0;
403		prev_pa = 0;
404	}
405
406	/* Dump memory chunks */
407	for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
408		bits = vm_page_dump[i];
409		while (bits) {
410			bit = ffs(bits) - 1;
411			pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) +
412			    bit) * PAGE_SIZE;
413			if (!count) {
414				prev_pa = pa;
415				count++;
416			} else {
417				if (pa == (prev_pa + count * PAGE_SIZE))
418					count++;
419				else {
420					error = blk_write_cont(di, prev_pa,
421					    count * PAGE_SIZE);
422					if (error)
423						goto fail;
424					count = 1;
425					prev_pa = pa;
426				}
427			}
428			bits &= ~(1ul << bit);
429		}
430	}
431	if (count) {
432		error = blk_write_cont(di, prev_pa, count * PAGE_SIZE);
433		if (error)
434			goto fail;
435		count = 0;
436		prev_pa = 0;
437	}
438
439	/* Dump trailer */
440	error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
441	if (error)
442		goto fail;
443	dumplo += sizeof(kdh);
444
445	/* Signal completion, signoff and exit stage left. */
446	dump_write(di, NULL, 0, 0, 0);
447	printf("\nDump complete\n");
448	return;
449
450fail:
451	if (error < 0)
452		error = -error;
453
454	if (error == ECANCELED)
455		printf("\nDump aborted\n");
456	else if (error == ENOSPC)
457		printf("\nDump failed. Partition too small.\n");
458	else
459		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
460}
461
462void
463dump_add_page(vm_paddr_t pa)
464{
465	int idx, bit;
466
467	pa >>= PAGE_SHIFT;
468	idx = pa >> 5;		/* 2^5 = 32 */
469	bit = pa & 31;
470	atomic_set_int(&vm_page_dump[idx], 1ul << bit);
471}
472
473void
474dump_drop_page(vm_paddr_t pa)
475{
476	int idx, bit;
477
478	pa >>= PAGE_SHIFT;
479	idx = pa >> 5;		/* 2^5 = 32 */
480	bit = pa & 31;
481	atomic_clear_int(&vm_page_dump[idx], 1ul << bit);
482}
483