1 files changed, 67 insertions, 0 deletions
diff --git a/kernel/kexec_handover.c b/kernel/kexec_handover.c
index 9cc818cefd15..69b953551677 100644
--- a/kernel/kexec_handover.c
+++ b/kernel/kexec_handover.c
@@ -26,6 +26,7 @@
  * internal APIs.
  */
 #include "../mm/internal.h"
+#include "kexec_internal.h"
 
 #define KHO_FDT_COMPATIBLE "kho-v1"
 #define PROP_PRESERVED_MEMORY_MAP "preserved-memory-map"
@@ -1197,3 +1198,69 @@ out:
 	if (err)
 		pr_warn("disabling KHO revival: %d\n", err);
 }
+
+/* Helper functions for kexec_file_load */
+
+int kho_fill_kimage(struct kimage *image)
+{
+	ssize_t scratch_size;
+	int err = 0;
+	struct kexec_buf scratch;
+
+	if (!kho_enable)
+		return 0;
+
+	image->kho.fdt = page_to_phys(kho_out.ser.fdt);
+
+	scratch_size = sizeof(*kho_scratch) * kho_scratch_cnt;
+	scratch = (struct kexec_buf){
+		.image = image,
+		.buffer = kho_scratch,
+		.bufsz = scratch_size,
+		.mem = KEXEC_BUF_MEM_UNKNOWN,
+		.memsz = scratch_size,
+		.buf_align = SZ_64K, /* Makes it easier to map */
+		.buf_max = ULONG_MAX,
+		.top_down = true,
+	};
+	err = kexec_add_buffer(&scratch);
+	if (err)
+		return err;
+	image->kho.scratch = &image->segment[image->nr_segments - 1];
+
+	return 0;
+}
+
+static int kho_walk_scratch(struct kexec_buf *kbuf,
+			    int (*func)(struct resource *, void *))
+{
+	int ret = 0;
+	int i;
+
+	for (i = 0; i < kho_scratch_cnt; i++) {
+		struct resource res = {
+			.start = kho_scratch[i].addr,
+			.end = kho_scratch[i].addr + kho_scratch[i].size - 1,
+		};
+
+		/* Try to fit the kimage into our KHO scratch region */
+		ret = func(&res, kbuf);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+int kho_locate_mem_hole(struct kexec_buf *kbuf,
+			int (*func)(struct resource *, void *))
+{
+	int ret;
+
+	if (!kho_enable || kbuf->image->type == KEXEC_TYPE_CRASH)
+		return 1;
+
+	ret = kho_walk_scratch(kbuf, func);
+
+	return ret == 1 ? 0 : -EADDRNOTAVAIL;
+}