[PATCH 06/13] kexec: New syscall kexec_file_load() declaration

Vivek Goyal
2014-06-03T13:08:33Z

This is the new syscall kexec_file_load() declaration/interface. I have
reserved the syscall number only for x86_64 so far. Other architectures
(including i386) can reserve syscall number when they enable the support
for this new syscall.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
arch/x86/syscalls/syscall_64.tbl | 1 +
include/linux/syscalls.h | 3 +++
kernel/kexec.c | 7 +++++++
kernel/sys_ni.c | 1 +
4 files changed, 12 insertions(+)

diff --git a/arch/x86/syscalls/syscall_64.tbl b/arch/x86/syscalls/syscall_64.tbl
index 04376ac..94482db 100644
--- a/arch/x86/syscalls/syscall_64.tbl
+++ b/arch/x86/syscalls/syscall_64.tbl
@@ -323,6 +323,7 @@
314 common sched_setattr sys_sched_setattr
315 common sched_getattr sys_sched_getattr
316 common renameat2 sys_renameat2
+317 common kexec_file_load sys_kexec_file_load

#
# x32-specific system call numbers start at 512 to avoid cache impact
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index a4a0588..9db7555 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -317,6 +317,9 @@ asmlinkage long sys_restart_syscall(void);
asmlinkage long sys_kexec_load(unsigned long entry, unsigned long nr_segments,
struct kexec_segment __user *segments,
unsigned long flags);
+asmlinkage long sys_kexec_file_load(int kernel_fd, int initrd_fd,
+ const char __user *cmdline_ptr,
+ unsigned long cmdline_len, unsigned long flags);

asmlinkage long sys_exit(int error_code);
asmlinkage long sys_exit_group(int error_code);
diff --git a/kernel/kexec.c b/kernel/kexec.c
index c435c5f..a3044e6 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1098,6 +1098,13 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
}
#endif

+SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
+ const char __user *, cmdline_ptr, unsigned long,
+ cmdline_len, unsigned long, flags)
+{
+ return -ENOSYS;
+}
+
void crash_kexec(struct pt_regs *regs)
{
/* Take the kexec_mutex here to prevent sys_kexec_load
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index bc8d1b7..4534626 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -25,6 +25,7 @@ cond_syscall(sys_swapon);
cond_syscall(sys_swapoff);
cond_syscall(sys_kexec_load);
cond_syscall(compat_sys_kexec_load);
+cond_syscall(sys_kexec_file_load);
cond_syscall(sys_init_module);
cond_syscall(sys_finit_module);
cond_syscall(sys_delete_module);
--
1.9.0