1 files changed, 320 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..e9b22bf
--- /dev/null
+++ b/kexec/arch/arm/crashdump-arm.c
@@ -0,0 +1,320 @@
+/*
+ * 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 <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 "crashdump-arm.h"
+
+static struct memory_range crash_memory_ranges[CRASH_MAX_MEMORY_RANGES];
+static int crash_memory_nr_ranges;
+
+/* memory range reserved for crashkernel */
+static struct memory_range crash_reserved_mem;
+
+static struct crash_elf_info elf_info = {
+	.class		= ELFCLASS32,
+	.data		= ELFDATA2LSB,
+	.machine	= EM_ARM,
+	.page_offset	= PAGE_OFFSET,
+};
+
+unsigned long phys_offset;
+
+/**
+ * crash_range_callback() - callback called for each iomem region
+ * @data: not used
+ * @nr: not used
+ * @str: name of the memory region
+ * @base: start address of the memory region
+ * @length: size of the memory region
+ *
+ * This function is called once for each memory region found in /proc/iomem. It
+ * locates system RAM and crashkernel reserved memory and places these to
+ * variables: @crash_memory_ranges and @crash_reserved_mem. Number of memory
+ * regions is placed in @crash_memory_nr_ranges.
+ */
+static int crash_range_callback(void *UNUSED(data), int UNUSED(nr),
+				char *str, unsigned long base,
+				unsigned long length)
+{
+	struct memory_range *range;
+
+	if (crash_memory_nr_ranges >= CRASH_MAX_MEMORY_RANGES)
+		return 1;
+
+	range = &crash_memory_ranges[crash_memory_nr_ranges];
+
+	if (strncmp(str, "System RAM\n", 11) == 0) {
+		range->start = base;
+		range->end = base + length - 1;
+		range->type = RANGE_RAM;
+		crash_memory_nr_ranges++;
+	} else if (strncmp(str, "Crash kernel\n", 13) == 0) {
+		crash_reserved_mem.start = base;
+		crash_reserved_mem.end = base + length - 1;
+		crash_reserved_mem.type = RANGE_RAM;
+	}
+
+	return 0;
+}
+
+/**
+ * crash_exclude_range() - excludes memory region reserved for crashkernel
+ *
+ * Function locates where crashkernel reserved memory is and removes that region
+ * from the available memory regions.
+ */
+static void crash_exclude_range(void)
+{
+	const struct memory_range *range = &crash_reserved_mem;
+	int i;
+
+	for (i = 0; i < crash_memory_nr_ranges; i++) {
+		struct memory_range *r = &crash_memory_ranges[i];
+
+		/*
+		 * We assume that crash area is fully contained in
+		 * some larger memory area.
+		 */
+		if (r->start <= range->start && r->end >= range->end) {
+			/*
+			 * Let's split this area into 2 smaller ones and
+			 * remove excluded range from between. First create
+			 * new entry for the remaining area.
+			 */
+			crash_memory_ranges[crash_memory_nr_ranges].start = range->end + 1;
+			crash_memory_ranges[crash_memory_nr_ranges].end = r->end;
+			crash_memory_nr_ranges++;
+			/*
+			 * Next update this area to end before excluded range.
+			 */
+			r->end = range->start - 1;
+			break;
+		}
+	}
+}
+
+static int range_cmp(const void *a1, const void *a2)
+{
+	const struct memory_range *r1 = a1;
+	const struct memory_range *r2 = a2;
+
+	if (r1->start > r2->start)
+		return 1;
+	if (r1->start < r2->start)
+		return -1;
+
+	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)
+{
+	/*
+	 * First read all memory regions that can be considered as
+	 * system memory including the crash area.
+	 */
+	kexec_iomem_for_each_line(NULL, crash_range_callback, NULL);
+
+	if (crash_memory_nr_ranges < 1) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	/*
+	 * Exclude memory reserved for crashkernel (this may result a split memory
+	 * region).
+	 */
+	crash_exclude_range();
+
+	/*
+	 * Make sure that the memory regions are sorted.
+	 */
+	qsort(crash_memory_ranges, crash_memory_nr_ranges,
+	      sizeof(crash_memory_ranges[0]), range_cmp);
+
+	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';
+}
+
+#ifdef DEBUG
+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;
+
+	dbgprintf("crashkernel: [%#llx - %#llx] (%ldM)\n",
+		  crash_reserved_mem.start, crash_reserved_mem.end,
+		  (unsigned long)range_size(&crash_reserved_mem) >> 20);
+
+	for (i = 0; i < crash_memory_nr_ranges; i++) {
+		struct memory_range *r = &crash_memory_ranges[i];
+		dbgprintf("memory range: [%#llx - %#llx] (%ldM)\n",
+			  r->start, r->end, (unsigned long)range_size(r) >> 20);
+	}
+}
+#else
+static inline void dump_memory_ranges(void) {}
+#endif
+
+/**
+ * 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;
+
+	/*
+	 * 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 = crash_memory_ranges[0].start;
+	dbgprintf("phys_offset: %#lx\n", phys_offset);
+
+	err = crash_create_elf32_headers(info, &elf_info, crash_memory_ranges,
+					 crash_memory_nr_ranges, &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_reserved_mem.start,
+					  crash_reserved_mem.end, -1, 0);
+
+	dbgprintf("elfcorehdr: %#lx\n", elfcorehdr);
+	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_reserved_mem.start);
+
+	dump_memory_ranges();
+	dbgprintf("kernel command line: \"%s\"\n", mod_cmdline);
+
+	return 0;
+}
+
+int is_crashkernel_mem_reserved(void)
+{
+	uint64_t start, end;
+
+	if (parse_iomem_single("Crash kernel\n", &start, &end) == 0)
+		return start != end;
+
+	return 0;
+}