[RFC v2][PATCH 1/9] Create trivial sys_checkpoint/sys_restart syscalls

[Oren Laadan]

this, of course, should be the last patch, not the first.

Oren Laadan wrote:
> Create trivial sys_checkpoint and sys_restore system calls. They will
> enable to checkpoint and restart an entire container, to and from a
> checkpoint image file.
> 
> First create a template for both syscalls: they take a file descriptor
> (for the image file) and flags as arguments. For sys_checkpoint the
> first argument identifies the target container; for sys_restart it will
> identify the checkpoint image.
> 
> Signed-off-by: Oren Laadan <orenl at cs.columbia.edu>
> ---
>   arch/x86/kernel/syscall_table_32.S |    2 ++
>   include/asm-x86/unistd_32.h        |    2 ++
>   include/linux/syscalls.h           |    2 ++
>   3 files changed, 6 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/kernel/syscall_table_32.S b/arch/x86/kernel/syscall_table_32.S
> index d44395f..5543136 100644
> --- a/arch/x86/kernel/syscall_table_32.S
> +++ b/arch/x86/kernel/syscall_table_32.S
> @@ -332,3 +332,5 @@ ENTRY(sys_call_table)
>   	.long sys_dup3			/* 330 */
>   	.long sys_pipe2
>   	.long sys_inotify_init1
> +	.long sys_checkpoint
> +	.long sys_restart
> diff --git a/include/asm-x86/unistd_32.h b/include/asm-x86/unistd_32.h
> index d739467..88bdec4 100644
> --- a/include/asm-x86/unistd_32.h
> +++ b/include/asm-x86/unistd_32.h
> @@ -338,6 +338,8 @@
>   #define __NR_dup3		330
>   #define __NR_pipe2		331
>   #define __NR_inotify_init1	332
> +#define __NR_checkpoint		333
> +#define __NR_restart		334
> 
>   #ifdef __KERNEL__
> 
> diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
> index d6ff145..edc218b 100644
> --- a/include/linux/syscalls.h
> +++ b/include/linux/syscalls.h
> @@ -622,6 +622,8 @@ asmlinkage long sys_timerfd_gettime(int ufd, struct itimerspec __user *otmr);
>   asmlinkage long sys_eventfd(unsigned int count);
>   asmlinkage long sys_eventfd2(unsigned int count, int flags);
>   asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, loff_t len);
> +asmlinkage long sys_checkpoint(pid_t pid, int fd, unsigned long flags);
> +asmlinkage long sys_restart(int crid, int fd, unsigned long flags);
> 
>   int kernel_execve(const char *filename, char *const argv[], char *const envp[]);
>