[PATCH v2 07/12] crashdump/ppc: Add print_crashkernel_region_size() function

[eric.devolder@xxxxxxxxxx (Eric DeVolder)]

From: Daniel Kiper <daniel.kiper@xxxxxxxxxx>

Follow similar x86 patch.

Signed-off-by: Daniel Kiper <daniel.kiper at oracle.com>
Signed-off-by: Eric DeVolder <eric.devolder at oracle.com>
---
 kexec/arch/ppc/crashdump-powerpc.c | 34 +++++++++++++++++++++++++++-------
 kexec/arch/ppc/kexec-ppc.c         | 23 +++++++++++++++++++++++
 kexec/arch/ppc/kexec-ppc.h         |  1 +
 3 files changed, 51 insertions(+), 7 deletions(-)

diff --git a/kexec/arch/ppc/crashdump-powerpc.c b/kexec/arch/ppc/crashdump-powerpc.c
index 3dc35eb..4c12452 100644
--- a/kexec/arch/ppc/crashdump-powerpc.c
+++ b/kexec/arch/ppc/crashdump-powerpc.c
@@ -397,14 +397,34 @@ 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;
+	if (get_devtree_value("/proc/device-tree/chosen/linux,crashkernel-base", &value)) {
+		*start = value;
+	}
+	else
+		*start = 0;
+	if (get_devtree_value("/proc/device-tree/chosen/linux,crashkernel-size", &value)) {
+		*end = *start + value - 1;
+	}
+	else
+		*end = 0;
+	return 0;
+}
+
 int is_crashkernel_mem_reserved(void)
 {
-	int fd;
-
-	fd = open("/proc/device-tree/chosen/linux,crashkernel-base", O_RDONLY);
-	if (fd < 0)
-		return 0;
-	close(fd);
-	return 1;
+	return get_devtree_value("/proc/device-tree/chosen/linux,crashkernel-base", NULL);
 }
 
+void print_crashkernel_region_size(void)
+{
+        uint64_t start = 0, end = 0;
+
+        if (is_crashkernel_mem_reserved()) {
+                get_crash_kernel_load_range(&start, &end);
+                printf("%llu\n", end - start + 1);
+        } else
+                printf("0\n");
+}
diff --git a/kexec/arch/ppc/kexec-ppc.c b/kexec/arch/ppc/kexec-ppc.c
index d046110..78e8fb8 100644
--- a/kexec/arch/ppc/kexec-ppc.c
+++ b/kexec/arch/ppc/kexec-ppc.c
@@ -423,6 +423,29 @@ err_out:
 	return -1;
 }
 
+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 rcode = 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);
+		rcode = 0;
+	}
+	if (pvalue) *pvalue = value;
+	return rcode;
+}
+
 /* Get devtree details and create exclude_range array
  * Also create usablemem_ranges for KEXEC_ON_CRASH
  */
diff --git a/kexec/arch/ppc/kexec-ppc.h b/kexec/arch/ppc/kexec-ppc.h
index 904cf48..69189f0 100644
--- a/kexec/arch/ppc/kexec-ppc.h
+++ b/kexec/arch/ppc/kexec-ppc.h
@@ -71,6 +71,7 @@ extern unsigned char reuse_initrd;
 extern const char *ramdisk;
 
 /* Method to parse the memory/reg nodes in device-tree */
+extern int get_devtree_value (const char *fname, unsigned long long *pvalue);
 extern unsigned long dt_address_cells, dt_size_cells;
 extern int init_memory_region_info(void);
 extern int read_memory_region_limits(int fd, unsigned long long *start,
-- 
2.7.4