[PATCH v16 10/12] arm64: Use OF alloc and free functions for FDT

[Lakshmi Ramasubramanian]

of_alloc_and_init_fdt() and of_free_fdt() have been defined in
drivers/of/kexec.c to allocate and free memory for FDT.

Use of_alloc_and_init_fdt() and of_free_fdt() to allocate and
initialize the FDT, and to free the FDT respectively.

Signed-off-by: Lakshmi Ramasubramanian <nra...@linux.microsoft.com>
Suggested-by: Rob Herring <r...@kernel.org>
---
 arch/arm64/kernel/machine_kexec_file.c | 37 +++++++-------------------
 1 file changed, 10 insertions(+), 27 deletions(-)

diff --git a/arch/arm64/kernel/machine_kexec_file.c 
b/arch/arm64/kernel/machine_kexec_file.c
index 7da22bb7b9d5..7d6cc478f73c 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
 
 int arch_kimage_file_post_load_cleanup(struct kimage *image)
 {
-       vfree(image->arch.dtb);
+       of_free_fdt(image->arch.dtb);
        image->arch.dtb = NULL;
 
        vfree(image->arch.elf_headers);
@@ -57,36 +57,19 @@ static int create_dtb(struct kimage *image,
        cmdline_len = cmdline ? strlen(cmdline) : 0;
        buf_size = fdt_totalsize(initial_boot_params)
                        + cmdline_len + DTB_EXTRA_SPACE;
-
-       for (;;) {
-               buf = vmalloc(buf_size);
-               if (!buf)
-                       return -ENOMEM;
-
-               /* duplicate a device tree blob */
-               ret = fdt_open_into(initial_boot_params, buf, buf_size);
-               if (ret)
-                       return -EINVAL;
-
-               ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
+       buf = of_alloc_and_init_fdt(buf_size);
+       if (!buf)
+               return -ENOMEM;
+       ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
                                             initrd_len, cmdline);
-               if (ret) {
-                       vfree(buf);
-                       if (ret == -ENOMEM) {
-                               /* unlikely, but just in case */
-                               buf_size += DTB_EXTRA_SPACE;
-                               continue;
-                       } else {
-                               return ret;
-                       }
-               }
-
+       if (!ret) {
                /* trim it */
                fdt_pack(buf);
                *dtb = buf;
+       } else
+               of_free_fdt(buf);
 
-               return 0;
-       }
+       return ret;
 }
 
 static int prepare_elf_headers(void **addr, unsigned long *sz)
@@ -224,6 +207,6 @@ int load_other_segments(struct kimage *image,
 
 out_err:
        image->nr_segments = orig_segments;
-       vfree(dtb);
+       of_free_fdt(dtb);
        return ret;
 }
-- 
2.30.0