vmtag is inconsistent in Minos, mvm and Linux

[ghost]

#40 changed Minos' struct vmtag, but did not change mvm's and Linux's. This leads to a problem that when creating a guest VM instead of a native VM, Minos gets a vmtag in a different format.

I think we need some mechanism to mark the version of vmtag, such as vmtag_size. And we need to ensure that new members are added to the end of vmtag.

By the way, I recommend maintaining the kernel mode code in this project, just like mvm.

[lemin9538]

#40 changed Minos' struct vmtag, but did not change mvm's and Linux's. This leads to a problem that when creating a guest VM instead of a native VM, Minos gets a vmtag in a different format.

I think we need some mechanism to mark the version of vmtag, such as vmtag_size. And we need to ensure that new members are added to the end of vmtag.

By the way, I recommend maintaining the kernel mode code in this project, just like mvm.

Very good suggestion.

For vmtag, may be we need a better way to replace it. We can brainstorm.

I already have related plans to make the kernel related code can be compiled into a kernel module. In addition, mvm and kernel module can be separated into separate git.

[lemin9538]

I think we can move below content from ramdisk.h to hypervisor.h. the definition of ramdisk may used in other tools or code, the purpose of hypervisor.h is used to share with different module (such as mvm and kernel), then other module only need copy the hypervisor.h to its code base.

#define RAMDISK_MAGIC	"MINOSRAMDISK...."
#define RAMDISK_MAGIC_SIZE 16

#define RAMDISK_FNAME_SIZE 32

struct ramdisk_inode {
	char fname[RAMDISK_FNAME_SIZE];
	uint64_t f_offset;	// data offset from ramdisk_start.
	uint64_t f_size;	// data size of this file
}__packed__;

struct ramdisk_sb {
	uint32_t file_cnt;
	uint32_t block_size;	// reserved
	uint64_t inode_offset;
	uint64_t data_base;	// reserved
};

struct ramdisk_file {
	struct ramdisk_inode *inode;
	unsigned long pos;	// reserved
};