Commit 28fc51d6 authored by Youling Tang's avatar Youling Tang Committed by Hongchen Zhang
Browse files

LoongArch: kexec: Add compatibility with old interfaces 

LoongArch inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I736HO



--------------------------------

Old interface:
a0 = argc, a1 = argv, a2 = envp

New interface:
a0 = efi flag, a2 = cmdline, a3 = systemtab

The following interfaces are not supported:
a0 = efi flag, a2 = small fdt

Signed-off-by: default avatarYouling Tang <tangyouling@loongson.cn>
Change-Id: If490ebe181ea75c955b93a69d28994f326938d93
parent b817dbdb

arch/loongarch/kernel/machine_kexec.c

+43 −2
Original line number Diff line number Diff line
@@ -59,6 +59,9 @@ static void kexec_image_info(const struct kimage *kimage) 
	}

}



#define MAX_ARGS 64

#define KEXEC_CMDLINE_SIZE (COMMAND_LINE_SIZE * 2)



int machine_kexec_prepare(struct kimage *kimage)

{

	int i;
@@ -70,11 +73,49 @@ int machine_kexec_prepare(struct kimage *kimage) 
	kimage->arch.efi_boot = fw_arg0;

	kimage->arch.systable_ptr = fw_arg2;



	if (!fw_arg2)

		pr_err("Small fdt mode is not supported!\n");



	/* Find the command line */

	for (i = 0; i < kimage->nr_segments; i++) {

		if (!strncmp(bootloader, (char __user *)kimage->segment[i].buf, strlen(bootloader))) {

			if (fw_arg0 < 2) {

				/* New firmware */

				if (!copy_from_user(cmdline_ptr, kimage->segment[i].buf, COMMAND_LINE_SIZE))

					kimage->arch.cmdline_ptr = (unsigned long)cmdline_ptr;

			} else {

				/* Old firmware */

				int argc = 0;

				long offt;

				char *ptr, *str;

				unsigned long *argv;



				/*

				 * convert command line string to array

				 * of parameters (as bootloader does).

				 */

				argv = (unsigned long *)kmalloc(KEXEC_CMDLINE_SIZE, GFP_KERNEL);

				argv[argc++] = (unsigned long)(KEXEC_CMDLINE_ADDR + KEXEC_CMDLINE_SIZE/2);

				str = (char *)argv + KEXEC_CMDLINE_SIZE/2;



				if (copy_from_user(str, kimage->segment[i].buf, KEXEC_CMDLINE_SIZE/2))

					return -EINVAL;



				ptr = strchr(str, ' ');



				while (ptr && (argc < MAX_ARGS)) {

					*ptr = '\0';

					if (ptr[1] != ' ') {

						offt = (long)(ptr - str + 1);

						argv[argc++] = (unsigned long)argv + KEXEC_CMDLINE_SIZE/2 + offt;

					}

					ptr = strchr(ptr + 1, ' ');

				}



				kimage->arch.efi_boot = argc;

				kimage->arch.cmdline_ptr = (unsigned long)argv;

				break;

			}

			break;

		}

	}