Using this helper allows us to avoid the in-kernel calls to the sys_ioperm() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_ioperm().
This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.ga17...@light.dominikbrodowski.net Cc: Ingo Molnar <mi...@redhat.com> Cc: Jiri Slaby <jsl...@suse.com> Cc: x...@kernel.org Acked-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> Reviewed-by: Thomas Gleixner <t...@linutronix.de> Signed-off-by: Dominik Brodowski <li...@dominikbrodowski.net> --- arch/x86/include/asm/syscalls.h | 1 + arch/x86/kernel/ioport.c | 7 ++++++- drivers/tty/vt/vt_ioctl.c | 6 +++--- 3 files changed, 10 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h index bad25bb80679..1c0bebbd039e 100644 --- a/arch/x86/include/asm/syscalls.h +++ b/arch/x86/include/asm/syscalls.h @@ -17,6 +17,7 @@ /* Common in X86_32 and X86_64 */ /* kernel/ioport.c */ +long ksys_ioperm(unsigned long from, unsigned long num, int turn_on); asmlinkage long sys_ioperm(unsigned long, unsigned long, int); asmlinkage long sys_iopl(unsigned int); diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c index 38deafebb21b..0fe1c8782208 100644 --- a/arch/x86/kernel/ioport.c +++ b/arch/x86/kernel/ioport.c @@ -23,7 +23,7 @@ /* * this changes the io permissions bitmap in the current task. */ -SYSCALL_DEFINE3(ioperm, unsigned long, from, unsigned long, num, int, turn_on) +long ksys_ioperm(unsigned long from, unsigned long num, int turn_on) { struct thread_struct *t = ¤t->thread; struct tss_struct *tss; @@ -96,6 +96,11 @@ SYSCALL_DEFINE3(ioperm, unsigned long, from, unsigned long, num, int, turn_on) return 0; } +SYSCALL_DEFINE3(ioperm, unsigned long, from, unsigned long, num, int, turn_on) +{ + return ksys_ioperm(from, num, turn_on); +} + /* * sys_iopl has to be used when you want to access the IO ports * beyond the 0x3ff range: to get the full 65536 ports bitmapped diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c index d61be307256a..a78ad10a119b 100644 --- a/drivers/tty/vt/vt_ioctl.c +++ b/drivers/tty/vt/vt_ioctl.c @@ -57,7 +57,7 @@ extern struct tty_driver *console_driver; */ #ifdef CONFIG_X86 -#include <linux/syscalls.h> +#include <asm/syscalls.h> #endif static void complete_change_console(struct vc_data *vc); @@ -420,12 +420,12 @@ int vt_ioctl(struct tty_struct *tty, ret = -EINVAL; break; } - ret = sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0; + ret = ksys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0; break; case KDENABIO: case KDDISABIO: - ret = sys_ioperm(GPFIRST, GPNUM, + ret = ksys_ioperm(GPFIRST, GPNUM, (cmd == KDENABIO)) ? -ENXIO : 0; break; #endif -- 2.16.3
