1 files changed, 388 insertions, 0 deletions
diff --git a/kexec/arch/arm/crashdump-arm.c b/kexec/arch/arm/crashdump-arm.c
new file mode 100644
index 0000000..1ec1826
--- /dev/null
+++ b/kexec/arch/arm/crashdump-arm.c
@@ -0,0 +1,388 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Copyright (C) Nokia Corporation, 2010.
+ * Author: Mika Westerberg
+ *
+ * Based on x86 implementation
+ * Copyright (C) IBM Corporation, 2005. All rights reserved
+ *
+ * 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.
+ */
+#include <limits.h>
+#include <elf.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "../../kexec.h"
+#include "../../kexec-elf.h"
+#include "../../crashdump.h"
+#include "../../mem_regions.h"
+#include "crashdump-arm.h"
+#include "iomem.h"
+#include "phys_to_virt.h"
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define ELFDATANATIVE ELFDATA2LSB
+#elif __BYTE_ORDER == __BIG_ENDIAN
+#define ELFDATANATIVE ELFDATA2MSB
+#else
+#error "Unknown machine endian"
+#endif
+
+/*
+ * Used to save various memory ranges/regions needed for the captured
+ * kernel to boot. (lime memmap= option in other archs)
+ */
+static struct memory_range crash_memory_ranges[CRASH_MAX_MEMORY_RANGES];
+struct memory_ranges usablemem_rgns = {
+	.max_size = CRASH_MAX_MEMORY_RANGES,
+	.ranges = crash_memory_ranges,
+};
+
+/* The boot-time physical memory range reserved for crashkernel region */
+struct memory_range crash_kernel_mem;
+
+/* reserved regions */
+#define CRASH_MAX_RESERVED_RANGES 2
+static struct memory_range crash_reserved_ranges[CRASH_MAX_RESERVED_RANGES];
+static struct memory_ranges crash_reserved_rgns = {
+	.max_size = CRASH_MAX_RESERVED_RANGES,
+	.ranges = crash_reserved_ranges,
+};
+
+struct memory_range elfcorehdr_mem;
+
+static struct crash_elf_info elf_info = {
+	.class		= ELFCLASS32,
+	.data		= ELFDATANATIVE,
+	.machine	= EM_ARM,
+	.page_offset	= DEFAULT_PAGE_OFFSET,
+};
+
+extern unsigned long long user_page_offset;
+
+static int get_kernel_page_offset(struct kexec_info *info,
+		struct crash_elf_info *elf_info)
+{
+	unsigned long long stext_sym_addr = get_kernel_sym("_stext");
+	if (stext_sym_addr == 0) {
+		if (user_page_offset != (-1ULL)) {
+			elf_info->page_offset = user_page_offset;
+			dbgprintf("Unable to get _stext symbol from /proc/kallsyms, "
+					"use user provided vaule: %llx\n",
+					elf_info->page_offset);
+			return 0;
+		}
+		elf_info->page_offset = (unsigned long long)DEFAULT_PAGE_OFFSET;
+		dbgprintf("Unable to get _stext symbol from /proc/kallsyms, "
+				"use default: %llx\n",
+				elf_info->page_offset);
+		return 0;
+	} else if ((user_page_offset != (-1ULL)) &&
+			(user_page_offset != stext_sym_addr)) {
+		fprintf(stderr, "PAGE_OFFSET is set to %llx "
+				"instead of user provided value %llx\n",
+				stext_sym_addr & (~KVBASE_MASK),
+				user_page_offset);
+	}
+	elf_info->page_offset = stext_sym_addr & (~KVBASE_MASK);
+	return 0;
+}
+
+/**
+ * crash_get_memory_ranges() - read system physical memory
+ *
+ * Function reads through system physical memory and stores found memory regions
+ * in @crash_memory_ranges. Number of memory regions found is placed in
+ * @crash_memory_nr_ranges. Regions are sorted in ascending order.
+ *
+ * Returns %0 in case of success and %-1 otherwise (errno is set).
+ */
+static int crash_get_memory_ranges(void)
+{
+	int i;
+
+	if (usablemem_rgns.size < 1) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	dbgprint_mem_range("Reserved memory ranges",
+			   crash_reserved_rgns.ranges,
+			   crash_reserved_rgns.size);
+
+	/*
+	 * Exclude all reserved memory from the usable memory regions.
+	 * We want to avoid dumping the crashkernel region itself.  Note
+	 * that this may result memory regions in usablemem_rgns being
+	 * split.
+	 */
+	for (i = 0; i < crash_reserved_rgns.size; i++) {
+		if (mem_regions_exclude(&usablemem_rgns,
+					&crash_reserved_rgns.ranges[i])) {
+			fprintf(stderr,
+				"Error: Number of crash memory ranges excedeed the max limit\n");
+			errno = ENOMEM;
+			return -1;
+		}
+	}
+
+	/*
+	 * Make sure that the memory regions are sorted.
+	 */
+	mem_regions_sort(&usablemem_rgns);
+
+	dbgprint_mem_range("Coredump memory ranges",
+			   usablemem_rgns.ranges, usablemem_rgns.size);
+
+	return 0;
+}
+
+/**
+ * cmdline_add_elfcorehdr() - adds elfcorehdr= to @cmdline
+ * @cmdline: buffer where parameter is placed
+ * @elfcorehdr: physical address of elfcorehdr
+ *
+ * Function appends 'elfcorehdr=start' at the end of the command line given in
+ * @cmdline. Note that @cmdline must be at least %COMMAND_LINE_SIZE bytes long
+ * (inclunding %NUL).
+ */
+static void cmdline_add_elfcorehdr(char *cmdline, unsigned long elfcorehdr)
+{
+	char buf[COMMAND_LINE_SIZE];
+	int buflen;
+
+	buflen = snprintf(buf, sizeof(buf), "%s elfcorehdr=%#lx",
+			  cmdline, elfcorehdr);
+	if (buflen < 0)
+		die("Failed to construct elfcorehdr= command line parameter\n");
+	if (buflen >= sizeof(buf))
+		die("Command line overflow\n");
+
+	(void) strncpy(cmdline, buf, COMMAND_LINE_SIZE);
+	cmdline[COMMAND_LINE_SIZE - 1] = '\0';
+}
+
+/**
+ * cmdline_add_mem() - adds mem= parameter to kernel command line
+ * @cmdline: buffer where parameter is placed
+ * @size: size of the kernel reserved memory (in bytes)
+ *
+ * This function appends 'mem=size' at the end of the command line given in
+ * @cmdline. Note that @cmdline must be at least %COMMAND_LINE_SIZE bytes long
+ * (including %NUL).
+ */
+static void cmdline_add_mem(char *cmdline, unsigned long size)
+{
+	char buf[COMMAND_LINE_SIZE];
+	int buflen;
+
+	buflen = snprintf(buf, sizeof(buf), "%s mem=%ldK", cmdline, size >> 10);
+	if (buflen < 0)
+		die("Failed to construct mem= command line parameter\n");
+	if (buflen >= sizeof(buf))
+		die("Command line overflow\n");
+
+	(void) strncpy(cmdline, buf, COMMAND_LINE_SIZE);
+	cmdline[COMMAND_LINE_SIZE - 1] = '\0';
+}
+
+static unsigned long long range_size(const struct memory_range *r)
+{
+	return r->end - r->start + 1;
+}
+
+static void dump_memory_ranges(void)
+{
+	int i;
+
+	if (!kexec_debug)
+		return;
+
+	dbgprintf("crashkernel: [%#llx - %#llx] (%ldM)\n",
+		  crash_kernel_mem.start, crash_kernel_mem.end,
+		  (unsigned long)range_size(&crash_kernel_mem) >> 20);
+
+	for (i = 0; i < usablemem_rgns.size; i++) {
+		struct memory_range *r = usablemem_rgns.ranges + i;
+		dbgprintf("memory range: [%#llx - %#llx] (%ldM)\n",
+			  r->start, r->end, (unsigned long)range_size(r) >> 20);
+	}
+}
+
+/**
+ * load_crashdump_segments() - loads additional segments needed for kdump
+ * @info: kexec info structure
+ * @mod_cmdline: kernel command line
+ *
+ * This function loads additional segments which are needed for the dump capture
+ * kernel. It also updates kernel command line passed in @mod_cmdline to have
+ * right parameters for the dump capture kernel.
+ *
+ * Return %0 in case of success and %-1 in case of error.
+ */
+int load_crashdump_segments(struct kexec_info *info, char *mod_cmdline)
+{
+	unsigned long elfcorehdr;
+	unsigned long bufsz;
+	void *buf;
+	int err;
+	int last_ranges;
+
+	/*
+	 * First fetch all the memory (RAM) ranges that we are going to pass to
+	 * the crashdump kernel during panic.
+	 */
+	err = crash_get_memory_ranges();
+	if (err)
+		return err;
+
+	/*
+	 * Now that we have memory regions sorted, we can use first memory
+	 * region as PHYS_OFFSET.
+	 */
+	phys_offset = usablemem_rgns.ranges->start;
+
+	if (get_kernel_page_offset(info, &elf_info))
+		return -1;
+
+	dbgprintf("phys offset = %#llx, page offset = %llx\n",
+		  phys_offset, elf_info.page_offset);
+
+	/*
+	 * Ensure that the crash kernel memory range is sane. The crash kernel
+	 * must be located within memory which is visible during booting.
+	 */
+	if (crash_kernel_mem.end > ARM_MAX_VIRTUAL) {
+		fprintf(stderr,
+			"Crash kernel memory [0x%llx-0x%llx] is inaccessible at boot - unable to load crash kernel\n",
+			crash_kernel_mem.start, crash_kernel_mem.end);
+		return -1;
+	}
+
+	last_ranges = usablemem_rgns.size - 1;
+	if (last_ranges < 0)
+		last_ranges = 0;
+
+	if (crash_memory_ranges[last_ranges].end > UINT32_MAX) {
+		dbgprintf("Using 64-bit ELF core format\n");
+
+		/* for support LPAE enabled kernel*/
+		elf_info.class = ELFCLASS64;
+
+		err = crash_create_elf64_headers(info, &elf_info,
+					 usablemem_rgns.ranges,
+					 usablemem_rgns.size, &buf, &bufsz,
+					 ELF_CORE_HEADER_ALIGN);
+	} else {
+		dbgprintf("Using 32-bit ELF core format\n");
+		err = crash_create_elf32_headers(info, &elf_info,
+					 usablemem_rgns.ranges,
+					 usablemem_rgns.size, &buf, &bufsz,
+					 ELF_CORE_HEADER_ALIGN);
+	}
+	if (err)
+		return err;
+
+	/*
+	 * We allocate ELF core header from the end of the memory area reserved
+	 * for the crashkernel. We align the header to SECTION_SIZE (which is
+	 * 1MB) so that available memory passed in kernel command line will be
+	 * aligned to 1MB. This is because kernel create_mapping() wants memory
+	 * regions to be aligned to SECTION_SIZE.
+	 */
+	elfcorehdr = add_buffer_phys_virt(info, buf, bufsz, bufsz, 1 << 20,
+					  crash_kernel_mem.start,
+					  crash_kernel_mem.end, -1, 0);
+
+	elfcorehdr_mem.start = elfcorehdr;
+	elfcorehdr_mem.end = elfcorehdr + bufsz - 1;
+
+	dbgprintf("elfcorehdr 0x%llx-0x%llx\n", elfcorehdr_mem.start,
+		  elfcorehdr_mem.end);
+	cmdline_add_elfcorehdr(mod_cmdline, elfcorehdr);
+
+	/*
+	 * Add 'mem=size' parameter to dump capture kernel command line. This
+	 * prevents the dump capture kernel from using any other memory regions
+	 * which belong to the primary kernel.
+	 */
+	cmdline_add_mem(mod_cmdline, elfcorehdr - crash_kernel_mem.start);
+
+	dump_memory_ranges();
+	dbgprintf("kernel command line: \"%s\"\n", mod_cmdline);
+
+	return 0;
+}
+
+/**
+ * iomem_range_callback() - callback called for each iomem region
+ * @data: not used
+ * @nr: not used
+ * @str: name of the memory region (not NULL terminated)
+ * @base: start address of the memory region
+ * @length: size of the memory region
+ *
+ * This function is called for each memory range in /proc/iomem, stores
+ * the location of the crash kernel range into @crash_kernel_mem, and
+ * stores the system RAM into @usablemem_rgns.
+ */
+static int iomem_range_callback(void *UNUSED(data), int UNUSED(nr),
+				char *str, unsigned long long base,
+				unsigned long long length)
+{
+	if (strncmp(str, CRASH_KERNEL_BOOT, strlen(CRASH_KERNEL_BOOT)) == 0) {
+		crash_kernel_mem.start = base;
+		crash_kernel_mem.end = base + length - 1;
+		crash_kernel_mem.type = RANGE_RAM;
+		return mem_regions_add(&crash_reserved_rgns,
+				       base, length, RANGE_RAM);
+	}
+	else if (strncmp(str, CRASH_KERNEL, strlen(CRASH_KERNEL)) == 0) {
+		if (crash_kernel_mem.start == crash_kernel_mem.end) {
+			crash_kernel_mem.start = base;
+			crash_kernel_mem.end = base + length - 1;
+			crash_kernel_mem.type = RANGE_RAM;
+		}
+		return mem_regions_add(&crash_reserved_rgns,
+				       base, length, RANGE_RAM);
+	}
+	else if (strncmp(str, SYSTEM_RAM, strlen(SYSTEM_RAM)) == 0) {
+		return mem_regions_add(&usablemem_rgns,
+				       base, length, RANGE_RAM);
+	}
+	return 0;
+}
+
+/**
+ * is_crashkernel_mem_reserved() - check for the crashkernel reserved region
+ *
+ * Check for the crashkernel reserved region in /proc/iomem, and return
+ * true if it is present, or false otherwise. We use this to store the
+ * location of this region, and system RAM regions.
+ */
+int is_crashkernel_mem_reserved(void)
+{
+	kexec_iomem_for_each_line(NULL, iomem_range_callback, NULL);
+
+	return crash_kernel_mem.start != crash_kernel_mem.end;
+}
+
+int get_crash_kernel_load_range(uint64_t *start, uint64_t *end)
+{
+	return parse_iomem_single("Crash kernel\n", start, end);
+}