[PATCH 1/8] arm: kdump: reserve memory for crashkernel
Mika Westerberg
ext-mika.1.westerberg at nokia.com
Tue Apr 20 04:50:47 EDT 2010
Implemented ARM support for command line option "crashkernel=size at start" which
allows user to reserve some memory for a dump capture kernel.
Signed-off-by: Mika Westerberg <ext-mika.1.westerberg at nokia.com>
---
arch/arm/kernel/setup.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 51 insertions(+), 0 deletions(-)
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index c91c77b..076454f 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -19,6 +19,7 @@
#include <linux/seq_file.h>
#include <linux/screen_info.h>
#include <linux/init.h>
+#include <linux/kexec.h>
#include <linux/root_dev.h>
#include <linux/cpu.h>
#include <linux/interrupt.h>
@@ -661,6 +662,55 @@ static int __init customize_machine(void)
}
arch_initcall(customize_machine);
+#ifdef CONFIG_KEXEC
+static inline unsigned long long get_total_mem(void)
+{
+ unsigned long total;
+
+ total = max_low_pfn - min_low_pfn;
+ return total << PAGE_SHIFT;
+}
+
+/**
+ * reserve_crashkernel() - reserves memory are for crash kernel
+ *
+ * This function reserves memory area given in "crashkernel=" kernel command
+ * line parameter. The memory reserved is used by a dump capture kernel when
+ * primary kernel is crashing.
+ */
+static void __init reserve_crashkernel(void)
+{
+ unsigned long long crash_size, crash_base;
+ unsigned long long total_mem;
+ int ret;
+
+ total_mem = get_total_mem();
+ ret = parse_crashkernel(boot_command_line, total_mem,
+ &crash_size, &crash_base);
+ if (ret)
+ return;
+
+ ret = reserve_bootmem(crash_base, crash_size, BOOTMEM_EXCLUSIVE);
+ if (ret < 0) {
+ printk(KERN_WARNING "crashkernel reservation failed - "
+ "memory is in use (0x%lx)\n", (unsigned long)crash_base);
+ return;
+ }
+
+ printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
+ "for crashkernel (System RAM: %ldMB)\n",
+ (unsigned long)(crash_size >> 20),
+ (unsigned long)(crash_base >> 20),
+ (unsigned long)(total_mem >> 20));
+
+ crashk_res.start = crash_base;
+ crashk_res.end = crash_base + crash_size - 1;
+ insert_resource(&iomem_resource, &crashk_res);
+}
+#else
+static inline void reserve_crashkernel(void) {}
+#endif /* CONFIG_KEXEC */
+
void __init setup_arch(char **cmdline_p)
{
struct tag *tags = (struct tag *)&init_tags;
@@ -720,6 +770,7 @@ void __init setup_arch(char **cmdline_p)
#ifdef CONFIG_SMP
smp_init_cpus();
#endif
+ reserve_crashkernel();
cpu_init();
tcm_init();
--
1.5.6.5
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