xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/entry/32: Enable pt_regs based syscalls

Browse Source 
Enable pt_regs based syscalls for 32-bit.  This makes the 32-bit native
kernel consistent with the 64-bit kernel, and improves the syscall
interface by not needing to push all 6 potential arguments onto the stack.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Link: https://lkml.kernel.org/r/20200313195144.164260-17-brgerst@gmail.com
This commit is contained in:
Brian Gerst
2020-03-13 15:51:42 -04:00
committed by Thomas Gleixner
parent 121b32a58a
commit 25c619e59b
6 changed files with 64 additions and 114 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
arch/x86/entry/syscall_32.c
View File

@@ -4,33 +4,22 @@
#include <linux/linkage.h>
#include <linux/sys.h>
#include <linux/cache.h>
#include <linux/syscalls.h>
#include <asm/unistd.h>
#include <asm/syscall.h>
#ifdef CONFIG_IA32_EMULATION
/* On X86_64, we use struct pt_regs * to pass parameters to syscalls */
#define __SYSCALL_I386(nr, sym) extern asmlinkage long __ia32_##sym(const struct pt_regs *);
#define __sys_ni_syscall __ia32_sys_ni_syscall
#else /* CONFIG_IA32_EMULATION */
#define __SYSCALL_I386(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
#define __sys_ni_syscall sys_ni_syscall
#endif /* CONFIG_IA32_EMULATION */
#include <asm/syscalls_32.h>
#undef __SYSCALL_I386
#ifdef CONFIG_IA32_EMULATION
#define __SYSCALL_I386(nr, sym) [nr] = __ia32_##sym,
#else /* CONFIG_IA32_EMULATION */
#define __SYSCALL_I386(nr, sym) [nr] = sym,
#endif /* CONFIG_IA32_EMULATION */
__visible const sys_call_ptr_t ia32_sys_call_table[__NR_ia32_syscall_max+1] = {
/*
* Smells like a compiler bug -- it doesn't work
* when the & below is removed.
*/
[0 ... __NR_ia32_syscall_max] = &__sys_ni_syscall,
[0 ... __NR_ia32_syscall_max] = &__ia32_sys_ni_syscall,
#include <asm/syscalls_32.h>
};