openrisc: add futex_atomic_* implementations (4ac46db1) · Commits · 戴 / test

arch/openrisc/include/asm/Kbuild

+0 −1

Original line number	Diff line number	Diff line
		@@ -20,7 +20,6 @@ generic-y += exec.h
		generic-y += fb.h
		generic-y += fcntl.h
		generic-y += ftrace.h
		generic-y += futex.h
		generic-y += hardirq.h
		generic-y += hw_irq.h
		generic-y += ioctl.h

arch/openrisc/include/asm/futex.h

0 → 100644

+135 −0

Original line number	Diff line number	Diff line
		#ifndef __ASM_OPENRISC_FUTEX_H
		#define __ASM_OPENRISC_FUTEX_H

		#ifdef __KERNEL__

		#include <linux/futex.h>
		#include <linux/uaccess.h>
		#include <asm/errno.h>

		#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
		({ \
		__asm__ __volatile__ ( \
		"1: l.lwa %0, %2 \n" \
		insn "\n" \
		"2: l.swa %2, %1 \n" \
		" l.bnf 1b \n" \
		" l.ori %1, r0, 0 \n" \
		"3: \n" \
		".section .fixup,\"ax\" \n" \
		"4: l.j 3b \n" \
		" l.addi %1, r0, %3 \n" \
		".previous \n" \
		".section __ex_table,\"a\" \n" \
		".word 1b,4b,2b,4b \n" \
		".previous \n" \
		: "=&r" (oldval), "=&r" (ret), "+m" (*uaddr) \
		: "i" (-EFAULT), "r" (oparg) \
		: "cc", "memory" \
		); \
		})

		static inline int
		futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
		{
		int op = (encoded_op >> 28) & 7;
		int cmp = (encoded_op >> 24) & 15;
		int oparg = (encoded_op << 8) >> 20;
		int cmparg = (encoded_op << 20) >> 20;
		int oldval = 0, ret;

		if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
		oparg = 1 << oparg;

		if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
		return -EFAULT;

		pagefault_disable();

		switch (op) {
		case FUTEX_OP_SET:
		__futex_atomic_op("l.or %1,%4,%4", ret, oldval, uaddr, oparg);
		break;
		case FUTEX_OP_ADD:
		__futex_atomic_op("l.add %1,%0,%4", ret, oldval, uaddr, oparg);
		break;
		case FUTEX_OP_OR:
		__futex_atomic_op("l.or %1,%0,%4", ret, oldval, uaddr, oparg);
		break;
		case FUTEX_OP_ANDN:
		__futex_atomic_op("l.and %1,%0,%4", ret, oldval, uaddr, ~oparg);
		break;
		case FUTEX_OP_XOR:
		__futex_atomic_op("l.xor %1,%0,%4", ret, oldval, uaddr, oparg);
		break;
		default:
		ret = -ENOSYS;
		}

		pagefault_enable();

		if (!ret) {
		switch (cmp) {
		case FUTEX_OP_CMP_EQ:
		ret = (oldval == cmparg);
		break;
		case FUTEX_OP_CMP_NE:
		ret = (oldval != cmparg);
		break;
		case FUTEX_OP_CMP_LT:
		ret = (oldval < cmparg);
		break;
		case FUTEX_OP_CMP_GE:
		ret = (oldval >= cmparg);
		break;
		case FUTEX_OP_CMP_LE:
		ret = (oldval <= cmparg);
		break;
		case FUTEX_OP_CMP_GT:
		ret = (oldval > cmparg);
		break;
		default:
		ret = -ENOSYS;
		}
		}
		return ret;
		}

		static inline int
		futex_atomic_cmpxchg_inatomic(u32 uval, u32 __user uaddr,
		u32 oldval, u32 newval)
		{
		int ret = 0;
		u32 prev;

		if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
		return -EFAULT;

		__asm__ __volatile__ ( \
		"1: l.lwa %1, %2 \n" \
		" l.sfeq %1, %3 \n" \
		" l.bnf 3f \n" \
		" l.nop \n" \
		"2: l.swa %2, %4 \n" \
		" l.bnf 1b \n" \
		" l.nop \n" \
		"3: \n" \
		".section .fixup,\"ax\" \n" \
		"4: l.j 3b \n" \
		" l.addi %0, r0, %5 \n" \
		".previous \n" \
		".section __ex_table,\"a\" \n" \
		".word 1b,4b,2b,4b \n" \
		".previous \n" \
		: "+r" (ret), "=&r" (prev), "+m" (*uaddr) \
		: "r" (oldval), "r" (newval), "i" (-EFAULT) \
		: "cc", "memory" \
		);

		*uval = prev;
		return ret;
		}

		#endif /* __KERNEL__ */

		#endif /* __ASM_OPENRISC_FUTEX_H */

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