kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE

Move the stuff currently only used by the kexec file code within
CONFIG_KEXEC_FILE (and CONFIG_KEXEC_VERIFY_SIG).

Also move internal "struct kexec_sha_region" and "struct kexec_buf" into
"kexec_internal.h".
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/kernel/machine_kexec_64.c

@@ -385,6 +385,7 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
 	return image->fops->cleanup(image->image_loader_data);
 }
 
+#ifdef CONFIG_KEXEC_VERIFY_SIG
 int arch_kexec_kernel_verify_sig(struct kimage *image, void *kernel,
 				 unsigned long kernel_len)
 {
@@ -395,6 +396,7 @@ int arch_kexec_kernel_verify_sig(struct kimage *image, void *kernel,
 
 	return image->fops->verify_sig(kernel, kernel_len);
 }
+#endif
 
 /*
  * Apply purgatory relocations.

include/linux/kexec.h

@@ -109,11 +109,7 @@ struct compat_kexec_segment {
 };
 #endif
 
-struct kexec_sha_region {
-	unsigned long start;
-	unsigned long len;
-};
-
+#ifdef CONFIG_KEXEC_FILE
 struct purgatory_info {
 	/* Pointer to elf header of read only purgatory */
 	Elf_Ehdr *ehdr;
@@ -130,6 +126,28 @@ struct purgatory_info {
 	unsigned long purgatory_load_addr;
 };
 
+typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
+typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
+			     unsigned long kernel_len, char *initrd,
+			     unsigned long initrd_len, char *cmdline,
+			     unsigned long cmdline_len);
+typedef int (kexec_cleanup_t)(void *loader_data);
+
+#ifdef CONFIG_KEXEC_VERIFY_SIG
+typedef int (kexec_verify_sig_t)(const char *kernel_buf,
+				 unsigned long kernel_len);
+#endif
+
+struct kexec_file_ops {
+	kexec_probe_t *probe;
+	kexec_load_t *load;
+	kexec_cleanup_t *cleanup;
+#ifdef CONFIG_KEXEC_VERIFY_SIG
+	kexec_verify_sig_t *verify_sig;
+#endif
+};
+#endif
+
 struct kimage {
 	kimage_entry_t head;
 	kimage_entry_t *entry;
@@ -161,6 +179,7 @@ struct kimage {
 	struct kimage_arch arch;
 #endif
 
+#ifdef CONFIG_KEXEC_FILE
 	/* Additional fields for file based kexec syscall */
 	void *kernel_buf;
 	unsigned long kernel_buf_len;
@@ -179,38 +198,7 @@ struct kimage {
 
 	/* Information for loading purgatory */
 	struct purgatory_info purgatory_info;
-};
-
-/*
- * Keeps track of buffer parameters as provided by caller for requesting
- * memory placement of buffer.
- */
-struct kexec_buf {
-	struct kimage *image;
-	char *buffer;
-	unsigned long bufsz;
-	unsigned long mem;
-	unsigned long memsz;
-	unsigned long buf_align;
-	unsigned long buf_min;
-	unsigned long buf_max;
-	bool top_down;		/* allocate from top of memory hole */
-};
-
-typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
-typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
-			     unsigned long kernel_len, char *initrd,
-			     unsigned long initrd_len, char *cmdline,
-			     unsigned long cmdline_len);
-typedef int (kexec_cleanup_t)(void *loader_data);
-typedef int (kexec_verify_sig_t)(const char *kernel_buf,
-				 unsigned long kernel_len);
-
-struct kexec_file_ops {
-	kexec_probe_t *probe;
-	kexec_load_t *load;
-	kexec_cleanup_t *cleanup;
-	kexec_verify_sig_t *verify_sig;
+#endif
 };
 
 /* kexec interface functions */

kernel/kexec_file.c

@@ -109,11 +109,13 @@ int __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
 	return -EINVAL;
 }
 
+#ifdef CONFIG_KEXEC_VERIFY_SIG
 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 					unsigned long buf_len)
 {
 	return -EKEYREJECTED;
 }
+#endif
 
 /* Apply relocations of type RELA */
 int __weak

kernel/kexec_internal.h

@@ -15,6 +15,27 @@ int kimage_is_destination_range(struct kimage *image,
 extern struct mutex kexec_mutex;
 
 #ifdef CONFIG_KEXEC_FILE
+struct kexec_sha_region {
+	unsigned long start;
+	unsigned long len;
+};
+
+/*
+ * Keeps track of buffer parameters as provided by caller for requesting
+ * memory placement of buffer.
+ */
+struct kexec_buf {
+	struct kimage *image;
+	char *buffer;
+	unsigned long bufsz;
+	unsigned long mem;
+	unsigned long memsz;
+	unsigned long buf_align;
+	unsigned long buf_min;
+	unsigned long buf_max;
+	bool top_down;		/* allocate from top of memory hole */
+};
+
 void kimage_file_post_load_cleanup(struct kimage *image);
 #else /* CONFIG_KEXEC_FILE */
 static inline void kimage_file_post_load_cleanup(struct kimage *image) { }