From 2fa1ef9e45b3ce6f7977a2518e58e177934f377c Mon Sep 17 00:00:00 2001

Message-Id: <2fa1ef9e45b3ce6f7977a2518e58e177934f377c.1489676829.git.panand@redhat.com>

In-Reply-To: <f85183096d31d865c97565614535d84943b12908.1489676829.git.panand@redhat.com>

References: <f85183096d31d865c97565614535d84943b12908.1489676829.git.panand@redhat.com>

From: AKASHI Takahiro <takahiro.akashi@linaro.org>

Date: Wed, 15 Mar 2017 18:38:19 +0900

Subject: [PATCH 05/10] arm64: kdump: identify memory regions

The following regions need to be identified for later use:

 a) memory regions which belong to the 1st kernel

 b) usable memory reserved for crash dump kernel

We go through /proc/iomem to find out a) and b) which are marked

as "System RAM" and "Crash kernel", respectively.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>

---

 kexec/arch/arm64/Makefile          |   2 +

 kexec/arch/arm64/crashdump-arm64.c | 100 ++++++++++++++++++++++++++++++++++++-

 kexec/arch/arm64/crashdump-arm64.h |  14 +++++-

 kexec/arch/arm64/iomem.h           |   1 +

 4 files changed, 114 insertions(+), 3 deletions(-)

diff --git a/kexec/arch/arm64/Makefile b/kexec/arch/arm64/Makefile

index 74b677f7784e..2d4ae0eed9e0 100644

--- a/kexec/arch/arm64/Makefile

+++ b/kexec/arch/arm64/Makefile

@@ -6,6 +6,8 @@ arm64_FS2DT_INCLUDE += \

 arm64_DT_OPS += kexec/dt-ops.c

+arm64_MEM_REGIONS = kexec/mem_regions.c

+

 arm64_CPPFLAGS += -I $(srcdir)/kexec/

 arm64_KEXEC_SRCS += \

diff --git a/kexec/arch/arm64/crashdump-arm64.c b/kexec/arch/arm64/crashdump-arm64.c

index d2272c8124d0..dcaca434af62 100644

--- a/kexec/arch/arm64/crashdump-arm64.c

+++ b/kexec/arch/arm64/crashdump-arm64.c

@@ -1,5 +1,13 @@

 /*

  * ARM64 crashdump.

+ *     partly derived from arm implementation

+ *

+ * Copyright (c) 2014-2016 Linaro Limited

+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>

+ *

+ * This program is free software; you can redistribute it and/or modify

+ * it under the terms of the GNU General Public License version 2 as

+ * published by the Free Software Foundation.

  */

 #define _GNU_SOURCE

@@ -10,12 +18,102 @@

 #include "kexec.h"

 #include "crashdump.h"

 #include "crashdump-arm64.h"

+#include "iomem.h"

 #include "kexec-arm64.h"

 #include "kexec-elf.h"

+#include "mem_regions.h"

-struct memory_ranges usablemem_rgns = {};

+/* memory ranges on crashed kernel */

+static struct memory_range crash_memory_ranges[CRASH_MAX_MEMORY_RANGES];

+static struct memory_ranges crash_memory_rgns = {

+	.size = 0,

+	.max_size = CRASH_MAX_MEMORY_RANGES,

+	.ranges = crash_memory_ranges,

+};

+

+/* memory range reserved for crashkernel */

+struct memory_range crash_reserved_mem;

+struct memory_ranges usablemem_rgns = {

+	.size = 0,

+	.max_size = 1,

+	.ranges = &crash_reserved_mem,

+};

+

+/*

+ * iomem_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, respectively, crash_memory_ranges and crash_reserved_mem.

+ */

+

+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, strlen(CRASH_KERNEL)) == 0)

+		return mem_regions_add(&usablemem_rgns,

+				       base, length, RANGE_RAM);

+	else if (strncmp(str, SYSTEM_RAM, strlen(SYSTEM_RAM)) == 0)

+		return mem_regions_add(&crash_memory_rgns,

+				       base, length, RANGE_RAM);

+

+	return 0;

+}

 int is_crashkernel_mem_reserved(void)

 {

+	if (!crash_reserved_mem.end)

+		kexec_iomem_for_each_line(NULL, iomem_range_callback, NULL);

+

+	return crash_reserved_mem.start != crash_reserved_mem.end;

+}

+

+/*

+ * crash_get_memory_ranges() - read system physical memory

+ *

+ * Function reads through system physical memory and stores found memory

+ * regions in crash_memory_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.

+	 */

+	if (!usablemem_rgns.size)

+		kexec_iomem_for_each_line(NULL, iomem_range_callback, NULL);

+

+	/* allow only a single region for crash dump kernel */

+	if (usablemem_rgns.size != 1) {

+		errno = EINVAL;

+		return -1;

+	}

+

+	dbgprint_mem_range("Reserved memory range", &crash_reserved_mem, 1);

+

+	if (mem_regions_exclude(&crash_memory_rgns, &crash_reserved_mem)) {

+		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(&crash_memory_rgns);

+

+	dbgprint_mem_range("Coredump memory ranges",

+			   crash_memory_rgns.ranges, crash_memory_rgns.size);

+

 	return 0;

 }

diff --git a/kexec/arch/arm64/crashdump-arm64.h b/kexec/arch/arm64/crashdump-arm64.h

index f33c7a25b454..07a0ed0bc344 100644

--- a/kexec/arch/arm64/crashdump-arm64.h

+++ b/kexec/arch/arm64/crashdump-arm64.h

@@ -1,12 +1,22 @@

 /*

  * ARM64 crashdump.

+ *

+ * Copyright (c) 2014-2016 Linaro Limited

+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>

+ *

+ * This program is free software; you can redistribute it and/or modify

+ * it under the terms of the GNU General Public License version 2 as

+ * published by the Free Software Foundation.

  */

-#if !defined(CRASHDUMP_ARM64_H)

+#ifndef CRASHDUMP_ARM64_H

 #define CRASHDUMP_ARM64_H

 #include "kexec.h"

+#define CRASH_MAX_MEMORY_RANGES	32

+

 extern struct memory_ranges usablemem_rgns;

+extern struct memory_range crash_reserved_mem;

-#endif

+#endif /* CRASHDUMP_ARM64_H */

diff --git a/kexec/arch/arm64/iomem.h b/kexec/arch/arm64/iomem.h

index 7fd66eb063e1..20cda87dbd02 100644

--- a/kexec/arch/arm64/iomem.h

+++ b/kexec/arch/arm64/iomem.h

@@ -2,6 +2,7 @@

 #define IOMEM_H

 #define SYSTEM_RAM		"System RAM\n"

+#define CRASH_KERNEL		"Crash kernel\n"

 #define IOMEM_RESERVED		"reserved\n"

 #endif

-- 

2.9.3