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-rw-r--r--kexec/arch/i386/kexec-x86-common.c444
1 files changed, 444 insertions, 0 deletions
diff --git a/kexec/arch/i386/kexec-x86-common.c b/kexec/arch/i386/kexec-x86-common.c
new file mode 100644
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--- /dev/null
+++ b/kexec/arch/i386/kexec-x86-common.c
@@ -0,0 +1,444 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Copyright (C) 2003-2005 Eric Biederman (ebiederm@xmission.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#define _XOPEN_SOURCE 600
+#define _BSD_SOURCE
+#define _DEFAULT_SOURCE
+
+#include <fcntl.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdint.h>
+#include <string.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include "../../kexec.h"
+#include "../../kexec-syscall.h"
+#include "../../firmware_memmap.h"
+#include "../../crashdump.h"
+#include "../../kexec-xen.h"
+#include "kexec-x86.h"
+#include "x86-linux-setup.h"
+
+/* Used below but not present in (older?) xenctrl.h */
+#ifndef E820_PMEM
+#define E820_PMEM 7
+#define E820_PRAM 12
+#endif
+
+/*
+ * The real mode IVT ends at 0x400.
+ * See https://wiki.osdev.org/Interrupt_Vector_Table.
+ */
+#define REALMODE_IVT_END 0x400
+
+static struct memory_range memory_range[MAX_MEMORY_RANGES];
+
+/**
+ * The old /proc/iomem parsing code.
+ *
+ * @param[out] range pointer that will be set to an array that holds the
+ * memory ranges
+ * @param[out] ranges number of ranges valid in @p range
+ *
+ * @return 0 on success, any other value on failure.
+ */
+static int get_memory_ranges_proc_iomem(struct memory_range **range, int *ranges)
+{
+ const char *iomem= proc_iomem();
+ int memory_ranges = 0;
+ char line[MAX_LINE];
+ FILE *fp;
+ fp = fopen(iomem, "r");
+ if (!fp) {
+ fprintf(stderr, "Cannot open %s: %s\n",
+ iomem, strerror(errno));
+ return -1;
+ }
+ while(fgets(line, sizeof(line), fp) != 0) {
+ unsigned long long start, end;
+ char *str;
+ int type;
+ int consumed;
+ int count;
+ if (memory_ranges >= MAX_MEMORY_RANGES)
+ break;
+ count = sscanf(line, "%llx-%llx : %n",
+ &start, &end, &consumed);
+ if (count != 2)
+ continue;
+ str = line + consumed;
+
+ dbgprintf("%016Lx-%016Lx : %s", start, end, str);
+
+ if (memcmp(str, "System RAM\n", 11) == 0) {
+ type = RANGE_RAM;
+ }
+ else if (strncasecmp(str, "reserved\n", 9) == 0) {
+ type = RANGE_RESERVED;
+ }
+ else if (memcmp(str, "ACPI Tables\n", 12) == 0) {
+ type = RANGE_ACPI;
+ }
+ else if (memcmp(str, "ACPI Non-volatile Storage\n", 26) == 0) {
+ type = RANGE_ACPI_NVS;
+ }
+ else if (memcmp(str, "Persistent Memory (legacy)\n", 27) == 0) {
+ type = RANGE_PRAM;
+ }
+ else if (memcmp(str, "Persistent Memory\n", 18) == 0) {
+ type = RANGE_PMEM;
+ }
+ else {
+ continue;
+ }
+ memory_range[memory_ranges].start = start;
+ memory_range[memory_ranges].end = end;
+ memory_range[memory_ranges].type = type;
+
+ dbgprintf("%016Lx-%016Lx : %x\n", start, end, type);
+
+ memory_ranges++;
+ }
+ fclose(fp);
+ *range = memory_range;
+ *ranges = memory_ranges;
+ return 0;
+}
+
+/**
+ * Calls the architecture independent get_firmware_memmap_ranges() to parse
+ * /sys/firmware/memmap and then do some x86 only modifications.
+ *
+ * @param[out] range pointer that will be set to an array that holds the
+ * memory ranges
+ * @param[out] ranges number of ranges valid in @p range
+ *
+ * @return 0 on success, any other value on failure.
+ */
+static int get_memory_ranges_sysfs(struct memory_range **range, int *ranges)
+{
+ int ret;
+ size_t range_number = MAX_MEMORY_RANGES;
+
+ ret = get_firmware_memmap_ranges(memory_range, &range_number);
+ if (ret != 0) {
+ fprintf(stderr, "Parsing the /sys/firmware memory map failed. "
+ "Falling back to /proc/iomem.\n");
+ return get_memory_ranges_proc_iomem(range, ranges);
+ }
+
+ *range = memory_range;
+ *ranges = range_number;
+
+ return 0;
+}
+
+#ifdef HAVE_LIBXENCTRL
+unsigned xen_e820_to_kexec_type(uint32_t type)
+{
+ switch (type) {
+ case E820_RAM:
+ return RANGE_RAM;
+ case E820_ACPI:
+ return RANGE_ACPI;
+ case E820_NVS:
+ return RANGE_ACPI_NVS;
+ case E820_PMEM:
+ return RANGE_PMEM;
+ case E820_PRAM:
+ return RANGE_PRAM;
+ case E820_RESERVED:
+ default:
+ return RANGE_RESERVED;
+ }
+}
+
+/**
+ * Memory map detection for Xen.
+ *
+ * @param[out] range pointer that will be set to an array that holds the
+ * memory ranges
+ * @param[out] ranges number of ranges valid in @p range
+ *
+ * @return 0 on success, any other value on failure.
+ */
+static int get_memory_ranges_xen(struct memory_range **range, int *ranges)
+{
+ int rc, ret = -1;
+ struct e820entry e820entries[MAX_MEMORY_RANGES];
+ unsigned int i;
+ xc_interface *xc;
+
+ xc = xc_interface_open(NULL, NULL, 0);
+
+ if (!xc) {
+ fprintf(stderr, "%s: Failed to open Xen control interface\n", __func__);
+ return -1;
+ }
+
+ rc = xc_get_machine_memory_map(xc, e820entries, MAX_MEMORY_RANGES);
+
+ if (rc < 0) {
+ fprintf(stderr, "%s: xc_get_machine_memory_map: %s\n", __func__, strerror(rc));
+ goto err;
+ }
+
+ for (i = 0; i < rc; ++i) {
+ memory_range[i].start = e820entries[i].addr;
+ memory_range[i].end = e820entries[i].addr + e820entries[i].size - 1;
+ memory_range[i].type = xen_e820_to_kexec_type(e820entries[i].type);
+ }
+
+ qsort(memory_range, rc, sizeof(struct memory_range), compare_ranges);
+
+ *range = memory_range;
+ *ranges = rc;
+
+ ret = 0;
+
+err:
+ xc_interface_close(xc);
+
+ return ret;
+}
+#else
+static int get_memory_ranges_xen(struct memory_range **range, int *ranges)
+{
+ return 0;
+}
+#endif /* HAVE_LIBXENCTRL */
+
+static void remove_range(struct memory_range *range, int nr_ranges, int index)
+{
+ int i, j;
+
+ for (i = index; i < (nr_ranges-1); i++) {
+ j = i+1;
+ range[i] = range[j];
+ }
+}
+
+/**
+ * Verifies and corrects any overlapping ranges.
+ * The ranges array is assumed to be sorted already.
+ *
+ * @param[out] range pointer that will be set to an array that holds the
+ * memory ranges
+ * @param[out] ranges number of ranges valid in @p range
+ *
+ * @return 0 on success, any other value on failure.
+ */
+static int fixup_memory_ranges(struct memory_range **range, int *ranges)
+{
+ int i;
+ int j;
+ int change_made;
+ int nr_ranges = *ranges;
+ struct memory_range *rp = *range;
+
+again:
+ change_made = 0;
+ for (i = 0; i < (nr_ranges-1); i++) {
+ j = i+1;
+ if (rp[i].start > rp[j].start) {
+ fprintf(stderr, "memory out of order!!\n");
+ return 1;
+ }
+
+ if (rp[i].type != rp[j].type)
+ continue;
+
+ if (rp[i].start == rp[j].start) {
+ if (rp[i].end >= rp[j].end) {
+ remove_range(rp, nr_ranges, j);
+ nr_ranges--;
+ change_made++;
+ } else {
+ remove_range(rp, nr_ranges, i);
+ nr_ranges--;
+ change_made++;
+ }
+ } else {
+ if (rp[i].end > rp[j].start) {
+ if (rp[i].end < rp[j].end) {
+ rp[j].start = rp[i].end;
+ change_made++;
+ } else if (rp[i].end >= rp[j].end) {
+ remove_range(rp, nr_ranges, j);
+ nr_ranges--;
+ change_made++;
+ }
+ }
+ }
+ }
+
+ /* fixing/removing an entry may make it wrong relative to the next */
+ if (change_made)
+ goto again;
+
+ *ranges = nr_ranges;
+ return 0;
+}
+
+/**
+ * Detect the add_efi_memmap kernel parameter.
+ *
+ * On some EFI-based systems, the e820 map is empty, or does not contain a
+ * complete memory map. The add_efi_memmap parameter adds these entries to
+ * the kernel's memory map, but does not add them under sysfs, which causes
+ * kexec to fail in a way similar to how it does not work on Xen.
+ *
+ * @return 1 if parameter is present, 0 if not or if an error occurs.
+ */
+int efi_map_added( void ) {
+ char buf[512];
+ FILE *fp = fopen( "/proc/cmdline", "r" );
+ if( fp ) {
+ fgets( buf, 512, fp );
+ fclose( fp );
+ return strstr( buf, "add_efi_memmap" ) != NULL;
+ } else {
+ return 0;
+ }
+}
+
+/**
+ * Return a sorted list of memory ranges.
+ *
+ * If we have the /sys/firmware/memmap interface, then use that. If not,
+ * or if parsing of that fails, use /proc/iomem as fallback.
+ *
+ * @param[out] range pointer that will be set to an array that holds the
+ * memory ranges
+ * @param[out] ranges number of ranges valid in @p range
+ * @param[in] kexec_flags the kexec_flags to determine if we load a normal
+ * or a crashdump kernel
+ *
+ * @return 0 on success, any other value on failure.
+ */
+int get_memory_ranges(struct memory_range **range, int *ranges,
+ unsigned long kexec_flags)
+{
+ int ret, i;
+
+ if (!efi_map_added() && !xen_present() && have_sys_firmware_memmap()) {
+ ret = get_memory_ranges_sysfs(range, ranges);
+ if (!ret)
+ ret = fixup_memory_ranges(range, ranges);
+ } else if (xen_present()) {
+ ret = get_memory_ranges_xen(range, ranges);
+ if (!ret)
+ ret = fixup_memory_ranges(range, ranges);
+ } else
+ ret = get_memory_ranges_proc_iomem(range, ranges);
+
+ /*
+ * get_memory_ranges_sysfs(), get_memory_ranges_proc_iomem() and
+ * get_memory_ranges_xen() have already printed an error message,
+ * so fail silently here.
+ */
+ if (ret != 0)
+ return ret;
+
+ /* Don't report the interrupt table as ram */
+ for (i = 0; i < *ranges; i++) {
+ if ((*range)[i].type == RANGE_RAM &&
+ ((*range)[i].start < REALMODE_IVT_END)) {
+ (*range)[i].start = REALMODE_IVT_END;
+ break;
+ }
+ }
+
+ /*
+ * Redefine the memory region boundaries if kernel
+ * exports the limits and if it is panic kernel.
+ * Override user values only if kernel exported values are
+ * subset of user defined values.
+ */
+ if ((kexec_flags & KEXEC_ON_CRASH) &&
+ !(kexec_flags & KEXEC_PRESERVE_CONTEXT)) {
+ uint64_t start, end;
+
+ ret = get_crash_kernel_load_range(&start, &end);
+ if (ret != 0) {
+ fprintf(stderr, "get_crash_kernel_load_range failed.\n");
+ return -1;
+ }
+
+ if (start > mem_min)
+ mem_min = start;
+ if (end < mem_max)
+ mem_max = end;
+ }
+
+ dbgprint_mem_range("MEMORY RANGES", *range, *ranges);
+
+ return ret;
+}
+
+static uint64_t bootparam_get_acpi_rsdp(void) {
+ uint64_t acpi_rsdp = 0;
+ off_t offset = offsetof(struct x86_linux_param_header, acpi_rsdp_addr);
+
+ if (get_bootparam(&acpi_rsdp, offset, sizeof(acpi_rsdp)))
+ return 0;
+
+ return acpi_rsdp;
+}
+
+static uint64_t efi_get_acpi_rsdp(void) {
+ FILE *fp;
+ char line[MAX_LINE], *s;
+ uint64_t acpi_rsdp = 0;
+
+ fp = fopen("/sys/firmware/efi/systab", "r");
+ if (!fp)
+ return acpi_rsdp;
+
+ while(fgets(line, sizeof(line), fp) != 0) {
+ /* ACPI20= always goes before ACPI= */
+ if ((strstr(line, "ACPI20=")) || (strstr(line, "ACPI="))) {
+ s = strchr(line, '=') + 1;
+ sscanf(s, "0x%lx", &acpi_rsdp);
+ break;
+ }
+ }
+ fclose(fp);
+
+ return acpi_rsdp;
+}
+
+uint64_t get_acpi_rsdp(void)
+{
+ uint64_t acpi_rsdp = 0;
+
+ acpi_rsdp = bootparam_get_acpi_rsdp();
+
+ if (!acpi_rsdp)
+ acpi_rsdp = efi_get_acpi_rsdp();
+
+ return acpi_rsdp;
+}
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