arm64: add kexec_file_load support

With this patch, kexec_file_load() system call is supported.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>

5 files changed, 55 insertions, 2 deletions

diff --git a/kexec/arch/arm64/kexec-arm64.c b/kexec/arch/arm64/kexec-arm64.c
index 536c64b0..1cde75d1 100644
--- a/kexec/arch/arm64/kexec-arm64.c
+++ b/kexec/arch/arm64/kexec-arm64.c
@@ -141,6 +141,7 @@ int arch_process_options(int argc, char **argv)
 	int opt;
 	char *cmdline = NULL;
 	const char *append = NULL;
+	int do_kexec_file_syscall = 0;
 
 	for (opt = 0; opt != -1; ) {
 		opt = getopt_long(argc, argv, short_options, options, 0);
@@ -158,6 +159,9 @@ int arch_process_options(int argc, char **argv)
 		case OPT_INITRD:
 			arm64_opts.initrd = optarg;
 			break;
+		case OPT_KEXEC_FILE_SYSCALL:
+			do_kexec_file_syscall = 1;
+			break;
 		default:
 			break; /* Ignore core and unknown options. */
 		}
@@ -169,7 +173,11 @@ int arch_process_options(int argc, char **argv)
 		arm64_opts.command_line);
 	dbgprintf("%s:%d: initrd: %s\n", __func__, __LINE__,
 		arm64_opts.initrd);
-	dbgprintf("%s:%d: dtb: %s\n", __func__, __LINE__, arm64_opts.dtb);
+	dbgprintf("%s:%d: dtb: %s\n", __func__, __LINE__,
+		(do_kexec_file_syscall && arm64_opts.dtb ? "(ignored)" :
+							arm64_opts.dtb));
+	if (do_kexec_file_syscall)
+		arm64_opts.dtb = NULL;
 
 	return 0;
 }
diff --git a/kexec/arch/arm64/kexec-elf-arm64.c b/kexec/arch/arm64/kexec-elf-arm64.c
index fc83b42c..e14f8e92 100644
--- a/kexec/arch/arm64/kexec-elf-arm64.c
+++ b/kexec/arch/arm64/kexec-elf-arm64.c
@@ -5,10 +5,12 @@
 #define _GNU_SOURCE
 
 #include <errno.h>
+#include <fcntl.h>
 #include <limits.h>
 #include <stdlib.h>
 #include <linux/elf.h>
 
+#include "arch/options.h"
 #include "crashdump-arm64.h"
 #include "kexec-arm64.h"
 #include "kexec-elf.h"
@@ -47,6 +49,13 @@ int elf_arm64_load(int argc, char **argv, const char *kernel_buf,
 	int result;
 	int i;
 
+	if (info->file_mode) {
+		fprintf(stderr,
+			"ELF executable is not supported in kexec_file\n");
+
+		return EFAILED;
+	}
+
 	result = build_elf_exec_info(kernel_buf, kernel_size, &ehdr, 0);
 
 	if (result < 0) {
diff --git a/kexec/arch/arm64/kexec-image-arm64.c b/kexec/arch/arm64/kexec-image-arm64.c
index e1b1e54b..685a9935 100644
--- a/kexec/arch/arm64/kexec-image-arm64.c
+++ b/kexec/arch/arm64/kexec-image-arm64.c
@@ -4,10 +4,15 @@
 
 #define _GNU_SOURCE
 
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
 #include "crashdump-arm64.h"
+#include "image-header.h"
+#include "kexec.h"
 #include "kexec-arm64.h"
 #include "kexec-syscall.h"
-#include <limits.h>
+#include "arch/options.h"
 
 int image_arm64_probe(const char *kernel_buf, off_t kernel_size)
 {
@@ -35,6 +40,27 @@ int image_arm64_load(int argc, char **argv, const char *kernel_buf,
 	unsigned long kernel_segment;
 	int result;
 
+	if (info->file_mode) {
+		if (arm64_opts.initrd) {
+			info->initrd_fd = open(arm64_opts.initrd, O_RDONLY);
+			if (info->initrd_fd == -1) {
+				fprintf(stderr,
+					"Could not open initrd file %s:%s\n",
+					arm64_opts.initrd, strerror(errno));
+				result = EFAILED;
+				goto exit;
+			}
+		}
+
+		if (arm64_opts.command_line) {
+			info->command_line = (char *)arm64_opts.command_line;
+			info->command_line_len =
+					strlen(arm64_opts.command_line) + 1;
+		}
+
+		return 0;
+	}
+
 	header = (const struct arm64_image_header *)(kernel_buf);
 
 	if (arm64_process_image_header(header))
diff --git a/kexec/arch/arm64/kexec-uImage-arm64.c b/kexec/arch/arm64/kexec-uImage-arm64.c
index 022d7ee4..126ea9c2 100644
--- a/kexec/arch/arm64/kexec-uImage-arm64.c
+++ b/kexec/arch/arm64/kexec-uImage-arm64.c
@@ -20,6 +20,13 @@ int uImage_arm64_load(int argc, char **argv, const char *buf, off_t len,
 	struct Image_info img;
 	int ret;
 
+	if (info->file_mode) {
+		fprintf(stderr,
+			"uImage is not supported in kexec_file\n");
+
+		return EFAILED;
+	}
+
 	ret = uImage_load(buf, len, &img);
 	if (ret)
 		return ret;
diff --git a/kexec/kexec-syscall.h b/kexec/kexec-syscall.h
index b96e02aa..dac1c1f7 100644
--- a/kexec/kexec-syscall.h
+++ b/kexec/kexec-syscall.h
@@ -67,6 +67,9 @@
 #ifdef __s390x__
 #define __NR_kexec_file_load	381
 #endif
+#ifdef __aarch64__
+#define __NR_kexec_file_load	294
+#endif
 
 #ifndef __NR_kexec_file_load
 /* system call not available for the arch */