PageRenderTime 34ms CodeModel.GetById 12ms app.highlight 16ms RepoModel.GetById 1ms app.codeStats 0ms

/arch/powerpc/include/asm/futex.h

https://github.com/aicjofs/android_kernel_lge_v500_20d_f2fs
C Header | 121 lines | 107 code | 14 blank | 0 comment | 8 complexity | 21212bf0c749a2e083e454b3d05eefbd MD5 | raw file
  1#ifndef _ASM_POWERPC_FUTEX_H
  2#define _ASM_POWERPC_FUTEX_H
  3
  4#ifdef __KERNEL__
  5
  6#include <linux/futex.h>
  7#include <linux/uaccess.h>
  8#include <asm/errno.h>
  9#include <asm/synch.h>
 10#include <asm/asm-compat.h>
 11
 12#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
 13  __asm__ __volatile ( \
 14	PPC_ATOMIC_ENTRY_BARRIER \
 15"1:	lwarx	%0,0,%2\n" \
 16	insn \
 17	PPC405_ERR77(0, %2) \
 18"2:	stwcx.	%1,0,%2\n" \
 19	"bne-	1b\n" \
 20	PPC_ATOMIC_EXIT_BARRIER \
 21	"li	%1,0\n" \
 22"3:	.section .fixup,\"ax\"\n" \
 23"4:	li	%1,%3\n" \
 24	"b	3b\n" \
 25	".previous\n" \
 26	".section __ex_table,\"a\"\n" \
 27	".align 3\n" \
 28	PPC_LONG "1b,4b,2b,4b\n" \
 29	".previous" \
 30	: "=&r" (oldval), "=&r" (ret) \
 31	: "b" (uaddr), "i" (-EFAULT), "r" (oparg) \
 32	: "cr0", "memory")
 33
 34static inline int futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr)
 35{
 36	int op = (encoded_op >> 28) & 7;
 37	int cmp = (encoded_op >> 24) & 15;
 38	int oparg = (encoded_op << 8) >> 20;
 39	int cmparg = (encoded_op << 20) >> 20;
 40	int oldval = 0, ret;
 41	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
 42		oparg = 1 << oparg;
 43
 44	if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32)))
 45		return -EFAULT;
 46
 47	pagefault_disable();
 48
 49	switch (op) {
 50	case FUTEX_OP_SET:
 51		__futex_atomic_op("mr %1,%4\n", ret, oldval, uaddr, oparg);
 52		break;
 53	case FUTEX_OP_ADD:
 54		__futex_atomic_op("add %1,%0,%4\n", ret, oldval, uaddr, oparg);
 55		break;
 56	case FUTEX_OP_OR:
 57		__futex_atomic_op("or %1,%0,%4\n", ret, oldval, uaddr, oparg);
 58		break;
 59	case FUTEX_OP_ANDN:
 60		__futex_atomic_op("andc %1,%0,%4\n", ret, oldval, uaddr, oparg);
 61		break;
 62	case FUTEX_OP_XOR:
 63		__futex_atomic_op("xor %1,%0,%4\n", ret, oldval, uaddr, oparg);
 64		break;
 65	default:
 66		ret = -ENOSYS;
 67	}
 68
 69	pagefault_enable();
 70
 71	if (!ret) {
 72		switch (cmp) {
 73		case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
 74		case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
 75		case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
 76		case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
 77		case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
 78		case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
 79		default: ret = -ENOSYS;
 80		}
 81	}
 82	return ret;
 83}
 84
 85static inline int
 86futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 87			      u32 oldval, u32 newval)
 88{
 89	int ret = 0;
 90	u32 prev;
 91
 92	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
 93		return -EFAULT;
 94
 95        __asm__ __volatile__ (
 96        PPC_ATOMIC_ENTRY_BARRIER
 97"1:     lwarx   %1,0,%3         # futex_atomic_cmpxchg_inatomic\n\
 98        cmpw    0,%1,%4\n\
 99        bne-    3f\n"
100        PPC405_ERR77(0,%3)
101"2:     stwcx.  %5,0,%3\n\
102        bne-    1b\n"
103        PPC_ATOMIC_EXIT_BARRIER
104"3:	.section .fixup,\"ax\"\n\
1054:	li	%0,%6\n\
106	b	3b\n\
107	.previous\n\
108	.section __ex_table,\"a\"\n\
109	.align 3\n\
110	" PPC_LONG "1b,4b,2b,4b\n\
111	.previous" \
112        : "+r" (ret), "=&r" (prev), "+m" (*uaddr)
113        : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT)
114        : "cc", "memory");
115
116	*uval = prev;
117        return ret;
118}
119
120#endif /* __KERNEL__ */
121#endif /* _ASM_POWERPC_FUTEX_H */