From 48a4c7874d8264ddbfaec2e9858d7866a2d2eb60 Mon Sep 17 00:00:00 2001 From: AKASHI Takahiro Date: Wed, 5 Aug 2015 13:16:30 +0900 Subject: [PATCH 4/9] 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. Upstream-Status: Backport [https://git.linaro.org/people/takahiro.akashi/kexec-tools.git] Signed-off-by: AKASHI Takahiro Signed-off-by: He Zhe --- 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 74b677f..2d4ae0e 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 d2272c8..dcaca43 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 + * + * 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 f33c7a2..07a0ed0 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 + * + * 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 7fd66eb..20cda87 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 -- 1.9.1