kvm: Add --params option

In particular this will keep boot agruments for kernel. The commit technically
prepares ground for real argument pass.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

include/kvm/kvm.h

@@ -25,7 +25,7 @@ struct kvm {
 
 struct kvm *kvm__init(void);
 void kvm__enable_singlestep(struct kvm *self);
-bool kvm__load_kernel(struct kvm *kvm, const char *kernel_filename);
+bool kvm__load_kernel(struct kvm *kvm, const char *kernel_filename, const char *kernel_cmdline);
 void kvm__reset_vcpu(struct kvm *self);
 void kvm__run(struct kvm *self);
 void kvm__emulate_io(struct kvm *self, uint16_t port, void *data, int direction, int size, uint32_t count);

kvm.c

@@ -194,7 +194,7 @@ static const char *BZIMAGE_MAGIC	= "HdrS";
 
 #define BZ_DEFAULT_SETUP_SECTS		4
 
-static bool load_bzimage(struct kvm *self, int fd)
+static bool load_bzimage(struct kvm *self, int fd, const char *kernel_cmdline)
 {
 	unsigned long setup_sects;
 	struct boot_params boot;
@@ -244,7 +244,8 @@ static bool load_bzimage(struct kvm *self, int fd)
 	return true;
 }
 
-bool kvm__load_kernel(struct kvm *kvm, const char *kernel_filename)
+bool kvm__load_kernel(struct kvm *kvm, const char *kernel_filename,
+			const char *kernel_cmdline)
 {
 	bool ret;
 	int fd;
@@ -253,7 +254,7 @@ bool kvm__load_kernel(struct kvm *kvm, const char *kernel_filename)
 	if (fd < 0)
 		die("unable to open kernel");
 
-	ret = load_bzimage(kvm, fd);
+	ret = load_bzimage(kvm, fd, kernel_cmdline);
 	if (ret)
 		goto found_kernel;
 

main.c

@@ -17,6 +17,7 @@ static void usage(char *argv[])
 int main(int argc, char *argv[])
 {
 	const char *kernel_filename = NULL;
+	const char *kernel_cmdline = NULL;
 	struct kvm *kvm;
 	int i;
 
@@ -24,6 +25,9 @@ int main(int argc, char *argv[])
 		if (!strncmp("--kernel=", argv[i], 9)) {
 			kernel_filename = &argv[i][9];
 			continue;
+		} else if (!strncmp("--params=", argv[i], 9)) {
+			kernel_cmdline = &argv[i][9];
+			continue;
 		} else {
 			/* any unspecified arg is kernel image */
 			if (argv[i][0] != '-')
@@ -39,7 +43,7 @@ int main(int argc, char *argv[])
 
 	kvm = kvm__init();
 
-	if (!kvm__load_kernel(kvm, kernel_filename))
+	if (!kvm__load_kernel(kvm, kernel_filename, kernel_cmdline))
 		die("unable to load kernel %s", kernel_filename);
 
 	kvm__reset_vcpu(kvm);