diff options
| -rw-r--r-- | arch/arm/include/asm/unistd.h | 7 | ||||
| -rw-r--r-- | arch/arm/kernel/entry-armv.S | 33 | ||||
| -rw-r--r-- | arch/arm/kernel/traps.c | 52 | ||||
| -rw-r--r-- | arch/arm/mm/Kconfig | 12 |
4 files changed, 3 insertions, 101 deletions
diff --git a/arch/arm/include/asm/unistd.h b/arch/arm/include/asm/unistd.h index 32640c431a08..8f63daf3efa3 100644 --- a/arch/arm/include/asm/unistd.h +++ b/arch/arm/include/asm/unistd.h @@ -21,13 +21,6 @@ */ #define __NR_syscalls (388) -/* - * *NOTE*: This is a ghost syscall private to the kernel. Only the - * __kuser_cmpxchg code in entry-armv.S should be aware of its - * existence. Don't ever use this from user code. - */ -#define __ARM_NR_cmpxchg (__ARM_NR_BASE+0x00fff0) - #define __ARCH_WANT_STAT64 #define __ARCH_WANT_SYS_GETHOSTNAME #define __ARCH_WANT_SYS_PAUSE diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 3e1c26eb32b4..3ce377f7251f 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -427,8 +427,7 @@ ENDPROC(__fiq_abt) .endm .macro kuser_cmpxchg_check -#if !defined(CONFIG_CPU_32v6K) && defined(CONFIG_KUSER_HELPERS) && \ - !defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG) +#if !defined(CONFIG_CPU_32v6K) && defined(CONFIG_KUSER_HELPERS) #ifndef CONFIG_MMU #warning "NPTL on non MMU needs fixing" #else @@ -859,20 +858,7 @@ __kuser_helper_start: __kuser_cmpxchg64: @ 0xffff0f60 -#if defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG) - - /* - * Poor you. No fast solution possible... - * The kernel itself must perform the operation. - * A special ghost syscall is used for that (see traps.c). - */ - stmfd sp!, {r7, lr} - ldr r7, 1f @ it's 20 bits - swi __ARM_NR_cmpxchg64 - ldmfd sp!, {r7, pc} -1: .word __ARM_NR_cmpxchg64 - -#elif defined(CONFIG_CPU_32v6K) +#if defined(CONFIG_CPU_32v6K) stmfd sp!, {r4, r5, r6, r7} ldrd r4, r5, [r0] @ load old val @@ -948,20 +934,7 @@ __kuser_memory_barrier: @ 0xffff0fa0 __kuser_cmpxchg: @ 0xffff0fc0 -#if defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG) - - /* - * Poor you. No fast solution possible... - * The kernel itself must perform the operation. - * A special ghost syscall is used for that (see traps.c). - */ - stmfd sp!, {r7, lr} - ldr r7, 1f @ it's 20 bits - swi __ARM_NR_cmpxchg - ldmfd sp!, {r7, pc} -1: .word __ARM_NR_cmpxchg - -#elif __LINUX_ARM_ARCH__ < 6 +#if __LINUX_ARM_ARCH__ < 6 #ifdef CONFIG_MMU diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 969f9d9e665f..bc698383e822 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -625,58 +625,6 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) set_tls(regs->ARM_r0); return 0; -#ifdef CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG - /* - * Atomically store r1 in *r2 if *r2 is equal to r0 for user space. - * Return zero in r0 if *MEM was changed or non-zero if no exchange - * happened. Also set the user C flag accordingly. - * If access permissions have to be fixed up then non-zero is - * returned and the operation has to be re-attempted. - * - * *NOTE*: This is a ghost syscall private to the kernel. Only the - * __kuser_cmpxchg code in entry-armv.S should be aware of its - * existence. Don't ever use this from user code. - */ - case NR(cmpxchg): - for (;;) { - extern void do_DataAbort(unsigned long addr, unsigned int fsr, - struct pt_regs *regs); - unsigned long val; - unsigned long addr = regs->ARM_r2; - struct mm_struct *mm = current->mm; - pgd_t *pgd; pmd_t *pmd; pte_t *pte; - spinlock_t *ptl; - - regs->ARM_cpsr &= ~PSR_C_BIT; - down_read(&mm->mmap_sem); - pgd = pgd_offset(mm, addr); - if (!pgd_present(*pgd)) - goto bad_access; - pmd = pmd_offset(pgd, addr); - if (!pmd_present(*pmd)) - goto bad_access; - pte = pte_offset_map_lock(mm, pmd, addr, &ptl); - if (!pte_present(*pte) || !pte_write(*pte) || !pte_dirty(*pte)) { - pte_unmap_unlock(pte, ptl); - goto bad_access; - } - val = *(unsigned long *)addr; - val -= regs->ARM_r0; - if (val == 0) { - *(unsigned long *)addr = regs->ARM_r1; - regs->ARM_cpsr |= PSR_C_BIT; - } - pte_unmap_unlock(pte, ptl); - up_read(&mm->mmap_sem); - return val; - - bad_access: - up_read(&mm->mmap_sem); - /* simulate a write access fault */ - do_DataAbort(addr, 15 + (1 << 11), regs); - } -#endif - default: /* Calls 9f00xx..9f07ff are defined to return -ENOSYS if not implemented, rather than raising SIGILL. This diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index df7537f12469..c21941349b3e 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -419,28 +419,24 @@ config CPU_THUMBONLY config CPU_32v3 bool select CPU_USE_DOMAINS if MMU - select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select NEED_KUSER_HELPERS select TLS_REG_EMUL if SMP || !MMU config CPU_32v4 bool select CPU_USE_DOMAINS if MMU - select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select NEED_KUSER_HELPERS select TLS_REG_EMUL if SMP || !MMU config CPU_32v4T bool select CPU_USE_DOMAINS if MMU - select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select NEED_KUSER_HELPERS select TLS_REG_EMUL if SMP || !MMU config CPU_32v5 bool select CPU_USE_DOMAINS if MMU - select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select NEED_KUSER_HELPERS select TLS_REG_EMUL if SMP || !MMU @@ -805,14 +801,6 @@ config TLS_REG_EMUL a few prototypes like that in existence) and therefore access to that required register must be emulated. -config NEEDS_SYSCALL_FOR_CMPXCHG - bool - select NEED_KUSER_HELPERS - help - SMP on a pre-ARMv6 processor? Well OK then. - Forget about fast user space cmpxchg support. - It is just not possible. - config NEED_KUSER_HELPERS bool |