diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S index 2ad4aa2a1536..55076a75e5bf 100644 --- a/arch/arm/kernel/calls.S +++ b/arch/arm/kernel/calls.S @@ -131,7 +131,7 @@ __syscall_start: .long sys_wait4 /* 115 */ .long sys_swapoff .long sys_sysinfo - .long sys_ipc_wrapper + .long sys_ipc .long sys_fsync .long sys_sigreturn_wrapper /* 120 */ .long sys_clone_wrapper @@ -254,7 +254,7 @@ __syscall_start: .long sys_fremovexattr .long sys_tkill .long sys_sendfile64 -/* 240 */ .long sys_futex_wrapper +/* 240 */ .long sys_futex .long sys_sched_setaffinity .long sys_sched_getaffinity .long sys_io_setup @@ -284,7 +284,7 @@ __syscall_start: .long sys_fstatfs64 .long sys_tgkill .long sys_utimes -/* 270 */ .long sys_arm_fadvise64_64_wrapper +/* 270 */ .long sys_arm_fadvise64_64 .long sys_pciconfig_iobase .long sys_pciconfig_read .long sys_pciconfig_write @@ -333,7 +333,7 @@ __syscall_start: .long sys_inotify_init .long sys_inotify_add_watch .long sys_inotify_rm_watch - .long sys_mbind_wrapper + .long sys_mbind /* 320 */ .long sys_get_mempolicy .long sys_set_mempolicy __syscall_end: diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index d9fb819bf7cc..2a8d27e18fa7 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -611,6 +611,47 @@ ENTRY(__switch_to) .globl __kuser_helper_start __kuser_helper_start: +/* + * Reference prototype: + * + * void __kernel_memory_barrier(void) + * + * Input: + * + * lr = return address + * + * Output: + * + * none + * + * Clobbered: + * + * the Z flag might be lost + * + * Definition and user space usage example: + * + * typedef void (__kernel_dmb_t)(void); + * #define __kernel_dmb (*(__kernel_dmb_t *)0xffff0fa0) + * + * Apply any needed memory barrier to preserve consistency with data modified + * manually and __kuser_cmpxchg usage. + * + * This could be used as follows: + * + * #define __kernel_dmb() \ + * asm volatile ( "mov r0, #0xffff0fff; mov lr, pc; sub pc, r0, #95" \ + * : : : "lr","cc" ) + */ + +__kuser_memory_barrier: @ 0xffff0fa0 + +#if __LINUX_ARM_ARCH__ >= 6 && defined(CONFIG_SMP) + mcr p15, 0, r0, c7, c10, 5 @ dmb +#endif + mov pc, lr + + .align 5 + /* * Reference prototype: * @@ -642,6 +683,8 @@ __kuser_helper_start: * The C flag is also set if *ptr was changed to allow for assembly * optimization in the calling code. * + * Note: this routine already includes memory barriers as needed. + * * For example, a user space atomic_add implementation could look like this: * * #define atomic_add(ptr, val) \ @@ -698,10 +741,16 @@ __kuser_cmpxchg: @ 0xffff0fc0 #else +#ifdef CONFIG_SMP + mcr p15, 0, r0, c7, c10, 5 @ dmb +#endif ldrex r3, [r2] subs r3, r3, r0 strexeq r3, r1, [r2] rsbs r0, r3, #0 +#ifdef CONFIG_SMP + mcr p15, 0, r0, c7, c10, 5 @ dmb +#endif mov pc, lr #endif diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index f7f183075237..e2b42997ad33 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -145,7 +145,7 @@ ENTRY(vector_swi) #endif enable_irq - str r4, [sp, #-S_OFF]! @ push fifth arg + stmdb sp!, {r4, r5} @ push fifth and sixth args get_thread_info tsk ldr ip, [tsk, #TI_FLAGS] @ check for syscall tracing @@ -204,7 +204,7 @@ ENTRY(sys_call_table) * Special system call wrappers */ @ r0 = syscall number -@ r5 = syscall table +@ r8 = syscall table .type sys_syscall, #function sys_syscall: eor scno, r0, #__NR_SYSCALL_BASE @@ -255,22 +255,6 @@ sys_sigaltstack_wrapper: ldr r2, [sp, #S_OFF + S_SP] b do_sigaltstack -sys_futex_wrapper: - str r5, [sp, #4] @ push sixth arg - b sys_futex - -sys_arm_fadvise64_64_wrapper: - str r5, [sp, #4] @ push r5 to stack - b sys_arm_fadvise64_64 - -sys_mbind_wrapper: - str r5, [sp, #4] - b sys_mbind - -sys_ipc_wrapper: - str r5, [sp, #4] @ push sixth arg - b sys_ipc - /* * Note: off_4k (r5) is always units of 4K. If we can't do the requested * offset, we return EINVAL.