diff options
Diffstat (limited to 'sys/x86/x86/dump_machdep.c')
-rw-r--r-- | sys/x86/x86/dump_machdep.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/sys/x86/x86/dump_machdep.c b/sys/x86/x86/dump_machdep.c new file mode 100644 index 0000000..d0a7612 --- /dev/null +++ b/sys/x86/x86/dump_machdep.c @@ -0,0 +1,373 @@ +/*- + * Copyright (c) 2002 Marcel Moolenaar + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/conf.h> +#include <sys/cons.h> +#include <sys/sysctl.h> +#include <sys/kernel.h> +#include <sys/kerneldump.h> +#include <vm/vm.h> +#include <vm/pmap.h> +#include <machine/elf.h> +#include <machine/md_var.h> + +#ifdef __amd64__ +#define KERNELDUMP_VERSION KERNELDUMP_AMD64_VERSION +#define EM_VALUE EM_X86_64 +#else +#define KERNELDUMP_VERSION KERNELDUMP_I386_VERSION +#define EM_VALUE EM_386 +#endif + +CTASSERT(sizeof(struct kerneldumpheader) == 512); + +int do_minidump = 1; +TUNABLE_INT("debug.minidump", &do_minidump); +SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RW, &do_minidump, 0, + "Enable mini crash dumps"); + +/* + * Don't touch the first SIZEOF_METADATA bytes on the dump device. This + * is to protect us from metadata and to protect metadata from us. + */ +#define SIZEOF_METADATA (64*1024) + +#define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK) +#define DEV_ALIGN(x) (((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1)) + +struct md_pa { + vm_paddr_t md_start; + vm_paddr_t md_size; +}; + +typedef int callback_t(struct md_pa *, int, void *); + +static struct kerneldumpheader kdh; +static off_t dumplo, fileofs; + +/* Handle buffered writes. */ +static char buffer[DEV_BSIZE]; +static size_t fragsz; + +/* 20 phys_avail entry pairs correspond to 10 md_pa's */ +static struct md_pa dump_map[10]; + +static void +md_pa_init(void) +{ + int n, idx; + + bzero(dump_map, sizeof(dump_map)); + for (n = 0; n < sizeof(dump_map) / sizeof(dump_map[0]); n++) { + idx = n * 2; + if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0) + break; + dump_map[n].md_start = dump_avail[idx]; + dump_map[n].md_size = dump_avail[idx + 1] - dump_avail[idx]; + } +} + +static struct md_pa * +md_pa_first(void) +{ + + return (&dump_map[0]); +} + +static struct md_pa * +md_pa_next(struct md_pa *mdp) +{ + + mdp++; + if (mdp->md_size == 0) + mdp = NULL; + return (mdp); +} + +static int +buf_write(struct dumperinfo *di, char *ptr, size_t sz) +{ + size_t len; + int error; + + while (sz) { + len = DEV_BSIZE - fragsz; + if (len > sz) + len = sz; + bcopy(ptr, buffer + fragsz, len); + fragsz += len; + ptr += len; + sz -= len; + if (fragsz == DEV_BSIZE) { + error = dump_write(di, buffer, 0, dumplo, + DEV_BSIZE); + if (error) + return error; + dumplo += DEV_BSIZE; + fragsz = 0; + } + } + + return (0); +} + +static int +buf_flush(struct dumperinfo *di) +{ + int error; + + if (fragsz == 0) + return (0); + + error = dump_write(di, buffer, 0, dumplo, DEV_BSIZE); + dumplo += DEV_BSIZE; + fragsz = 0; + return (error); +} + +#define PG2MB(pgs) ((pgs + (1 << 8) - 1) >> 8) + +static int +cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg) +{ + struct dumperinfo *di = (struct dumperinfo*)arg; + vm_paddr_t a, pa; + void *va; + uint64_t pgs; + size_t counter, sz, chunk; + int i, c, error, twiddle; + u_int maxdumppgs; + + error = 0; /* catch case in which chunk size is 0 */ + counter = 0; /* Update twiddle every 16MB */ + twiddle = 0; + va = 0; + pgs = mdp->md_size / PAGE_SIZE; + pa = mdp->md_start; + maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS); + if (maxdumppgs == 0) /* seatbelt */ + maxdumppgs = 1; + + printf(" chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs), + (uintmax_t)pgs); + + while (pgs) { + chunk = pgs; + if (chunk > maxdumppgs) + chunk = maxdumppgs; + sz = chunk << PAGE_SHIFT; + counter += sz; + if (counter >> 24) { + printf(" %ju", (uintmax_t)PG2MB(pgs)); + counter &= (1<<24) - 1; + } + for (i = 0; i < chunk; i++) { + a = pa + i * PAGE_SIZE; + va = pmap_kenter_temporary(trunc_page(a), i); + } + error = dump_write(di, va, 0, dumplo, sz); + if (error) + break; + dumplo += sz; + pgs -= chunk; + pa += sz; + + /* Check for user abort. */ + c = cncheckc(); + if (c == 0x03) + return (ECANCELED); + if (c != -1) + printf(" (CTRL-C to abort) "); + } + printf(" ... %s\n", (error) ? "fail" : "ok"); + return (error); +} + +static int +cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg) +{ + struct dumperinfo *di = (struct dumperinfo*)arg; + Elf_Phdr phdr; + uint64_t size; + int error; + + size = mdp->md_size; + bzero(&phdr, sizeof(phdr)); + phdr.p_type = PT_LOAD; + phdr.p_flags = PF_R; /* XXX */ + phdr.p_offset = fileofs; + phdr.p_vaddr = mdp->md_start; + phdr.p_paddr = mdp->md_start; + phdr.p_filesz = size; + phdr.p_memsz = size; + phdr.p_align = PAGE_SIZE; + + error = buf_write(di, (char*)&phdr, sizeof(phdr)); + fileofs += phdr.p_filesz; + return (error); +} + +static int +cb_size(struct md_pa *mdp, int seqnr, void *arg) +{ + uint64_t *sz = (uint64_t*)arg; + + *sz += (uint64_t)mdp->md_size; + return (0); +} + +static int +foreach_chunk(callback_t cb, void *arg) +{ + struct md_pa *mdp; + int error, seqnr; + + seqnr = 0; + mdp = md_pa_first(); + while (mdp != NULL) { + error = (*cb)(mdp, seqnr++, arg); + if (error) + return (-error); + mdp = md_pa_next(mdp); + } + return (seqnr); +} + +void +dumpsys(struct dumperinfo *di) +{ + Elf_Ehdr ehdr; + uint64_t dumpsize; + off_t hdrgap; + size_t hdrsz; + int error; + + if (do_minidump) { + minidumpsys(di); + return; + } + bzero(&ehdr, sizeof(ehdr)); + ehdr.e_ident[EI_MAG0] = ELFMAG0; + ehdr.e_ident[EI_MAG1] = ELFMAG1; + ehdr.e_ident[EI_MAG2] = ELFMAG2; + ehdr.e_ident[EI_MAG3] = ELFMAG3; + ehdr.e_ident[EI_CLASS] = ELF_CLASS; +#if BYTE_ORDER == LITTLE_ENDIAN + ehdr.e_ident[EI_DATA] = ELFDATA2LSB; +#else + ehdr.e_ident[EI_DATA] = ELFDATA2MSB; +#endif + ehdr.e_ident[EI_VERSION] = EV_CURRENT; + ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */ + ehdr.e_type = ET_CORE; + ehdr.e_machine = EM_VALUE; + ehdr.e_phoff = sizeof(ehdr); + ehdr.e_flags = 0; + ehdr.e_ehsize = sizeof(ehdr); + ehdr.e_phentsize = sizeof(Elf_Phdr); + ehdr.e_shentsize = sizeof(Elf_Shdr); + + md_pa_init(); + + /* Calculate dump size. */ + dumpsize = 0L; + ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize); + hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize; + fileofs = MD_ALIGN(hdrsz); + dumpsize += fileofs; + hdrgap = fileofs - DEV_ALIGN(hdrsz); + + /* Determine dump offset on device. */ + if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) { + error = ENOSPC; + goto fail; + } + dumplo = di->mediaoffset + di->mediasize - dumpsize; + dumplo -= sizeof(kdh) * 2; + + mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_VERSION, dumpsize, + di->blocksize); + + printf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20, + ehdr.e_phnum); + + /* Dump leader */ + error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh)); + if (error) + goto fail; + dumplo += sizeof(kdh); + + /* Dump ELF header */ + error = buf_write(di, (char*)&ehdr, sizeof(ehdr)); + if (error) + goto fail; + + /* Dump program headers */ + error = foreach_chunk(cb_dumphdr, di); + if (error < 0) + goto fail; + buf_flush(di); + + /* + * All headers are written using blocked I/O, so we know the + * current offset is (still) block aligned. Skip the alignement + * in the file to have the segment contents aligned at page + * boundary. We cannot use MD_ALIGN on dumplo, because we don't + * care and may very well be unaligned within the dump device. + */ + dumplo += hdrgap; + + /* Dump memory chunks (updates dumplo) */ + error = foreach_chunk(cb_dumpdata, di); + if (error < 0) + goto fail; + + /* Dump trailer */ + error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh)); + if (error) + goto fail; + + /* Signal completion, signoff and exit stage left. */ + dump_write(di, NULL, 0, 0, 0); + printf("\nDump complete\n"); + return; + + fail: + if (error < 0) + error = -error; + + if (error == ECANCELED) + printf("\nDump aborted\n"); + else if (error == ENOSPC) + printf("\nDump failed. Partition too small.\n"); + else + printf("\n** DUMP FAILED (ERROR %d) **\n", error); +} |