[PATCH v3 08/11] crashdump/ppc64: Add get_crash_kernel_load_range() function

[Eric DeVolder]

From: Daniel Kiper <daniel.kiper at oracle.com>

Implement get_crash_kernel_load_range() in support of
print crash kernel region size option.

Signed-off-by: Daniel Kiper <daniel.kiper at oracle.com>
Signed-off-by: Eric DeVolder <eric.devolder at oracle.com>
---
 kexec/arch/ppc64/crashdump-ppc64.c | 21 +++++++++++++++++++++
 kexec/arch/ppc64/kexec-ppc64.c     | 27 +++++++++++++++++++++++++++
 kexec/arch/ppc64/kexec-ppc64.h     |  2 ++
 3 files changed, 50 insertions(+)

diff --git a/kexec/arch/ppc64/crashdump-ppc64.c b/kexec/arch/ppc64/crashdump-ppc64.c
index f62b159..af9adb4 100644
--- a/kexec/arch/ppc64/crashdump-ppc64.c
+++ b/kexec/arch/ppc64/crashdump-ppc64.c
@@ -526,6 +526,27 @@ void add_usable_mem_rgns(unsigned long long base, unsigned long long size)
 		usablemem_rgns.size, base, size);
 }
 
+int get_crash_kernel_load_range(uint64_t *start, uint64_t *end)
+{
+	unsigned long long value;
+	int ret = 0;
+
+	if (get_devtree_value("/proc/device-tree/chosen/linux,crashkernel-base", &value))
+		*start = value;
+	else {
+		*start = 0;
+		ret = -1;
+	}
+	if (get_devtree_value("/proc/device-tree/chosen/linux,crashkernel-size", &value))
+		*end = *start + value - 1;
+	else {
+		*end = 0;
+		ret = -1;
+	}
+
+	return ret;
+}
+
 int is_crashkernel_mem_reserved(void)
 {
 	int fd;
diff --git a/kexec/arch/ppc64/kexec-ppc64.c b/kexec/arch/ppc64/kexec-ppc64.c
index 09ee025..33bc76f 100644
--- a/kexec/arch/ppc64/kexec-ppc64.c
+++ b/kexec/arch/ppc64/kexec-ppc64.c
@@ -356,6 +356,33 @@ void scan_reserved_ranges(unsigned long kexec_flags, int *range_index)
 	*range_index = i;
 }
 
+int get_devtree_value(const char *fname, unsigned long long *pvalue)
+{
+	/* Return 1 if fname/value valid, 0 otherwise */
+	FILE *file;
+	char buf[MAXBYTES];
+	int ret = 1, n = -1;
+	unsigned long long value = 0;
+
+	if ((file = fopen(fname, "r"))) {
+		n = fread(buf, 1, MAXBYTES, file);
+		fclose(file);
+	}
+
+	if (n == sizeof(uint32_t))
+		value = ((uint32_t *)buf)[0];
+	else if (n == sizeof(uint64_t))
+		value = ((uint64_t *)buf)[0];
+	else {
+		fprintf(stderr, "%s node has invalid size: %d\n", fname, n);
+		ret = 0;
+	}
+
+	if (pvalue)
+		*pvalue = value;
+	return ret;
+}
+
 /* Get devtree details and create exclude_range array
  * Also create usablemem_ranges for KEXEC_ON_CRASH
  */
diff --git a/kexec/arch/ppc64/kexec-ppc64.h b/kexec/arch/ppc64/kexec-ppc64.h
index 89ee942..3d20419 100644
--- a/kexec/arch/ppc64/kexec-ppc64.h
+++ b/kexec/arch/ppc64/kexec-ppc64.h
@@ -14,6 +14,8 @@
 #define HAVE_DYNAMIC_MEMORY
 #define NEED_RESERVE_DTB
 
+extern int get_devtree_value (const char *fname, unsigned long long *pvalue);
+
 int setup_memory_ranges(unsigned long kexec_flags);
 
 int elf_ppc64_probe(const char *buf, off_t len);
-- 
2.7.4