[RFC v7][PATCH 1/9] Create syscalls: sys_checkpoint, sys_restart
From: Oren Laadan <hidden>
Date: 2008-10-20 05:42:58
Also in:
linux-mm, lkml
Subsystem:
abi/api, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
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 descriptor. The syscalls 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 <redacted> Acked-by: Serge Hallyn <redacted> Signed-off-by: Dave Hansen <redacted> --- arch/x86/kernel/syscall_table_32.S | 2 + checkpoint/Kconfig | 11 +++++++++ checkpoint/Makefile | 5 ++++ checkpoint/sys.c | 41 ++++++++++++++++++++++++++++++++++++ include/asm-x86/unistd_32.h | 2 + include/linux/syscalls.h | 2 + init/Kconfig | 2 + kernel/sys_ni.c | 4 +++ 8 files changed, 69 insertions(+), 0 deletions(-) create mode 100644 checkpoint/Kconfig create mode 100644 checkpoint/Makefile create mode 100644 checkpoint/sys.c
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/checkpoint/Kconfig b/checkpoint/Kconfig
new file mode 100644
index 0000000..ffaa635
--- /dev/null
+++ b/checkpoint/Kconfig@@ -0,0 +1,11 @@ +config CHECKPOINT_RESTART + prompt "Enable checkpoint/restart (EXPERIMENTAL)" + def_bool n + depends on X86_32 && EXPERIMENTAL + help + Application checkpoint/restart is the ability to save the + state of a running application so that it can later resume + its execution from the time at which it was checkpointed. + + Turning this option on will enable checkpoint and restart + functionality in the kernel.
diff --git a/checkpoint/Makefile b/checkpoint/Makefile
new file mode 100644
index 0000000..07d018b
--- /dev/null
+++ b/checkpoint/Makefile@@ -0,0 +1,5 @@ +# +# Makefile for linux checkpoint/restart. +# + +obj-$(CONFIG_CHECKPOINT_RESTART) += sys.o
diff --git a/checkpoint/sys.c b/checkpoint/sys.c
new file mode 100644
index 0000000..375129c
--- /dev/null
+++ b/checkpoint/sys.c@@ -0,0 +1,41 @@ +/* + * Generic container checkpoint-restart + * + * Copyright (C) 2008 Oren Laadan + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of the Linux + * distribution for more details. + */ + +#include <linux/sched.h> +#include <linux/kernel.h> + +/** + * sys_checkpoint - checkpoint a container + * @pid: pid of the container init(1) process + * @fd: file to which dump the checkpoint image + * @flags: checkpoint operation flags + * + * Returns positive identifier on success, 0 when returning from restart + * or negative value on error + */ +asmlinkage long sys_checkpoint(pid_t pid, int fd, unsigned long flags) +{ + pr_debug("sys_checkpoint not implemented yet\n"); + return -ENOSYS; +} +/** + * sys_restart - restart a container + * @crid: checkpoint image identifier + * @fd: file from which read the checkpoint image + * @flags: restart operation flags + * + * Returns negative value on error, or otherwise returns in the realm + * of the original checkpoint + */ +asmlinkage long sys_restart(int crid, int fd, unsigned long flags) +{ + pr_debug("sys_restart not implemented yet\n"); + return -ENOSYS; +}
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[]);
diff --git a/init/Kconfig b/init/Kconfig
index c11da38..fd5f7bf 100644
--- a/init/Kconfig
+++ b/init/Kconfig@@ -779,6 +779,8 @@ config MARKERS source "arch/Kconfig" +source "checkpoint/Kconfig" + config PROC_PAGE_MONITOR default y depends on PROC_FS && MMU
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 08d6e1b..ca95c25 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c@@ -168,3 +168,7 @@ cond_syscall(compat_sys_timerfd_settime); cond_syscall(compat_sys_timerfd_gettime); cond_syscall(sys_eventfd); cond_syscall(sys_eventfd2); + +/* checkpoint/restart */ +cond_syscall(sys_checkpoint); +cond_syscall(sys_restart);
--
1.5.4.3