1 files changed, 65 insertions, 5 deletions

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 35cf0ad29718..f1d0e00a3971 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -16,6 +16,7 @@
 #include <linux/file.h>
 #include <linux/slab.h>
 #include <linux/kexec.h>
+#include <linux/memblock.h>
 #include <linux/mutex.h>
 #include <linux/list.h>
 #include <linux/fs.h>
@@ -76,7 +77,7 @@ void * __weak arch_kexec_kernel_image_load(struct kimage *image)
 	return kexec_image_load_default(image);
 }
 
-static int kexec_image_post_load_cleanup_default(struct kimage *image)
+int kexec_image_post_load_cleanup_default(struct kimage *image)
 {
 	if (!image->fops || !image->fops->cleanup)
 		return 0;
@@ -499,8 +500,60 @@ static int locate_mem_hole_callback(struct resource *res, void *arg)
 	return locate_mem_hole_bottom_up(start, end, kbuf);
 }
 
+#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
+static int kexec_walk_memblock(struct kexec_buf *kbuf,
+			       int (*func)(struct resource *, void *))
+{
+	return 0;
+}
+#else
+static int kexec_walk_memblock(struct kexec_buf *kbuf,
+			       int (*func)(struct resource *, void *))
+{
+	int ret = 0;
+	u64 i;
+	phys_addr_t mstart, mend;
+	struct resource res = { };
+
+	if (kbuf->image->type == KEXEC_TYPE_CRASH)
+		return func(&crashk_res, kbuf);
+
+	if (kbuf->top_down) {
+		for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE,
+						&mstart, &mend, NULL) {
+			/*
+			 * In memblock, end points to the first byte after the
+			 * range while in kexec, end points to the last byte
+			 * in the range.
+			 */
+			res.start = mstart;
+			res.end = mend - 1;
+			ret = func(&res, kbuf);
+			if (ret)
+				break;
+		}
+	} else {
+		for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
+					&mstart, &mend, NULL) {
+			/*
+			 * In memblock, end points to the first byte after the
+			 * range while in kexec, end points to the last byte
+			 * in the range.
+			 */
+			res.start = mstart;
+			res.end = mend - 1;
+			ret = func(&res, kbuf);
+			if (ret)
+				break;
+		}
+	}
+
+	return ret;
+}
+#endif
+
 /**
- * arch_kexec_walk_mem - call func(data) on free memory regions
+ * kexec_walk_resources - call func(data) on free memory regions
  * @kbuf:	Context info for the search. Also passed to @func.
  * @func:	Function to call for each memory region.
  *
@@ -508,8 +561,8 @@ static int locate_mem_hole_callback(struct resource *res, void *arg)
  * and that value will be returned. If all free regions are visited without
  * func returning non-zero, then zero will be returned.
  */
-int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
-			       int (*func)(struct resource *, void *))
+static int kexec_walk_resources(struct kexec_buf *kbuf,
+				int (*func)(struct resource *, void *))
 {
 	if (kbuf->image->type == KEXEC_TYPE_CRASH)
 		return walk_iomem_res_desc(crashk_res.desc,
@@ -532,7 +585,14 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf)
 {
 	int ret;
 
-	ret = arch_kexec_walk_mem(kbuf, locate_mem_hole_callback);
+	/* Arch knows where to place */
+	if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
+		return 0;
+
+	if (IS_ENABLED(CONFIG_ARCH_DISCARD_MEMBLOCK))
+		ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
+	else
+		ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);
 
 	return ret == 1 ? 0 : -EADDRNOTAVAIL;
 }