Re: [PATCH 3/3 V2] kvm tools: Add cmdline options for loading multiple images

[David Ahern <dsahern@gmail.com>]

On 05/04/11 07:45, Sasha Levin wrote:
> This is a simple cmdline addition to allow loading multiple images.
> perf's cmdline parser doesn't support having multiple args
> with the same name (i.e. --image <img1> --image <img2>), so
> we have to choose either to extend the parser, or find a diiferent
> way to assign multiple images.
> 
> Sample cmdline for loading 2 images:
> ./kvm run --image=image1.raw --readonly --image2=image2.raw --readonly2

syntax is getting a bit unwieldy. Why not use a scheme similar to qemu
and concatenate related arguments into one and handle multiple usages?
e.g., --image=image1.raw,ro --image=image2.raw,ro

David


> 
> NOTE NOTE NOTE - If testing, Please take notice of the
> --readonly param changes so you won't destroy your image/disk.
> 
> Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
> ---
>  tools/kvm/kvm-run.c |   36 ++++++++++++++++++++++++------------
>  1 files changed, 24 insertions(+), 12 deletions(-)
> 
> diff --git a/tools/kvm/kvm-run.c b/tools/kvm/kvm-run.c
> index b92232d..5182735 100644
> --- a/tools/kvm/kvm-run.c
> +++ b/tools/kvm/kvm-run.c
> @@ -42,6 +42,7 @@
>  #define MB_SHIFT		(20)
>  #define MIN_RAM_SIZE_MB		(64ULL)
>  #define MIN_RAM_SIZE_BYTE	(MIN_RAM_SIZE_MB << MB_SHIFT)
> +#define MAX_DISK_IMAGES		4
>  
>  static struct kvm *kvm;
>  static struct kvm_cpu *kvm_cpus[KVM_NR_CPUS];
> @@ -51,7 +52,7 @@ static u64 ram_size = MIN_RAM_SIZE_MB;
>  static const char *kernel_cmdline;
>  static const char *kernel_filename;
>  static const char *initrd_filename;
> -static const char *image_filename;
> +static const char *image_filename[MAX_DISK_IMAGES];
>  static const char *console;
>  static const char *kvm_dev;
>  static const char *network;
> @@ -59,7 +60,7 @@ static const char *host_ip_addr;
>  static const char *guest_mac;
>  static const char *script;
>  static bool single_step;
> -static bool readonly_image;
> +static bool readonly_image[MAX_DISK_IMAGES];
>  static bool virtio_rng;
>  extern bool ioport_debug;
>  extern int  active_console;
> @@ -75,8 +76,17 @@ static const struct option options[] = {
>  	OPT_GROUP("Basic options:"),
>  	OPT_INTEGER('\0', "cpus", &nrcpus, "Number of CPUs"),
>  	OPT_U64('m', "mem", &ram_size, "Virtual machine memory size in MiB."),
> -	OPT_STRING('i', "image", &image_filename, "image", "Disk image"),
> -	OPT_BOOLEAN('\0', "readonly", &readonly_image,
> +	OPT_STRING('i', "image", &image_filename[0], "image", "Disk image"),
> +	OPT_BOOLEAN('\0', "readonly", &readonly_image[0],
> +			"Don't write changes back to disk image"),
> +	OPT_STRING('\0', "image2", &image_filename[1], "image", "Disk image"),
> +	OPT_BOOLEAN('\0', "readonly2", &readonly_image[1],
> +			"Don't write changes back to disk image"),
> +	OPT_STRING('\0', "image3", &image_filename[2], "image", "Disk image"),
> +	OPT_BOOLEAN('\0', "readonly3", &readonly_image[2],
> +			"Don't write changes back to disk image"),
> +	OPT_STRING('\0', "image4", &image_filename[3], "image", "Disk image"),
> +	OPT_BOOLEAN('\0', "readonly4", &readonly_image[3],
>  			"Don't write changes back to disk image"),
>  	OPT_STRING('c', "console", &console, "serial or virtio",
>  			"Console to use"),
> @@ -397,23 +407,25 @@ int kvm_cmd_run(int argc, const char **argv, const char *prefix)
>  		strlcat(real_cmdline, kernel_cmdline, sizeof(real_cmdline));
>  
>  	hi = NULL;
> -	if (!image_filename) {
> +	if (!image_filename[0]) {
>  		hi = host_image(real_cmdline, sizeof(real_cmdline));
>  		if (hi) {
> -			image_filename = hi;
> -			readonly_image = true;
> +			image_filename[0] = hi;
> +			readonly_image[0] = true;
>  		}
>  	}
>  
>  	if (!strstr(real_cmdline, "root="))
>  		strlcat(real_cmdline, " root=/dev/vda rw ", sizeof(real_cmdline));
>  
> -	if (image_filename) {
> -		struct disk_image *disk = disk_image__open(image_filename, readonly_image);
> -		if (!disk)
> -			die("unable to load disk image %s", image_filename);
> +	for (i = 0; i < MAX_DISK_IMAGES; i++) {
> +		if (image_filename[i]) {
> +			struct disk_image *disk = disk_image__open(image_filename[i], readonly_image[i]);
> +			if (!disk)
> +				die("unable to load disk image %s", image_filename[i]);
>  
> -		virtio_blk__init(kvm, disk);
> +			virtio_blk__init(kvm, disk);
> +		}
>  	}
>  	free(hi);
>