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Diffstat (limited to 'arch/xtensa/include/asm/futex.h')
-rw-r--r--arch/xtensa/include/asm/futex.h172
1 files changed, 96 insertions, 76 deletions
diff --git a/arch/xtensa/include/asm/futex.h b/arch/xtensa/include/asm/futex.h
index b39531babec0..a6f7d7ab5950 100644
--- a/arch/xtensa/include/asm/futex.h
+++ b/arch/xtensa/include/asm/futex.h
@@ -1,12 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Atomic futex routines
*
* Based on the PowerPC implementataion
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
* Copyright (C) 2013 TangoTec Ltd.
*
* Baruch Siach <baruch@tkos.co.il>
@@ -15,133 +12,156 @@
#ifndef _ASM_XTENSA_FUTEX_H
#define _ASM_XTENSA_FUTEX_H
-#ifdef __KERNEL__
-
#include <linux/futex.h>
#include <linux/uaccess.h>
#include <linux/errno.h>
-#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
+#define arch_futex_atomic_op_inuser arch_futex_atomic_op_inuser
+#define futex_atomic_cmpxchg_inatomic futex_atomic_cmpxchg_inatomic
+#include <asm-generic/futex.h>
+
+#if XCHAL_HAVE_EXCLUSIVE
+#define __futex_atomic_op(insn, ret, old, uaddr, arg) \
__asm__ __volatile( \
- "1: l32i %0, %2, 0\n" \
+ "1: l32ex %[oldval], %[addr]\n" \
insn "\n" \
- " wsr %0, scompare1\n" \
- "2: s32c1i %1, %2, 0\n" \
- " bne %1, %0, 1b\n" \
- " movi %1, 0\n" \
+ "2: s32ex %[newval], %[addr]\n" \
+ " getex %[newval]\n" \
+ " beqz %[newval], 1b\n" \
+ " movi %[newval], 0\n" \
"3:\n" \
" .section .fixup,\"ax\"\n" \
" .align 4\n" \
- "4: .long 3b\n" \
- "5: l32r %0, 4b\n" \
- " movi %1, %3\n" \
- " jx %0\n" \
+ " .literal_position\n" \
+ "5: movi %[oldval], 3b\n" \
+ " movi %[newval], %[fault]\n" \
+ " jx %[oldval]\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
- " .long 1b,5b,2b,5b\n" \
+ " .long 1b, 5b, 2b, 5b\n" \
" .previous\n" \
- : "=&r" (oldval), "=&r" (ret) \
- : "r" (uaddr), "I" (-EFAULT), "r" (oparg) \
+ : [oldval] "=&r" (old), [newval] "=&r" (ret) \
+ : [addr] "r" (uaddr), [oparg] "r" (arg), \
+ [fault] "I" (-EFAULT) \
: "memory")
+#elif XCHAL_HAVE_S32C1I
+#define __futex_atomic_op(insn, ret, old, uaddr, arg) \
+ __asm__ __volatile( \
+ "1: l32i %[oldval], %[mem]\n" \
+ insn "\n" \
+ " wsr %[oldval], scompare1\n" \
+ "2: s32c1i %[newval], %[mem]\n" \
+ " bne %[newval], %[oldval], 1b\n" \
+ " movi %[newval], 0\n" \
+ "3:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 4\n" \
+ " .literal_position\n" \
+ "5: movi %[oldval], 3b\n" \
+ " movi %[newval], %[fault]\n" \
+ " jx %[oldval]\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .long 1b, 5b, 2b, 5b\n" \
+ " .previous\n" \
+ : [oldval] "=&r" (old), [newval] "=&r" (ret), \
+ [mem] "+m" (*(uaddr)) \
+ : [oparg] "r" (arg), [fault] "I" (-EFAULT) \
+ : "memory")
+#endif
-static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
+static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
+ 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;
+#if XCHAL_HAVE_S32C1I || XCHAL_HAVE_EXCLUSIVE
int oldval = 0, ret;
- if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
- oparg = 1 << oparg;
- if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+ if (!access_ok(uaddr, sizeof(u32)))
return -EFAULT;
-#if !XCHAL_HAVE_S32C1I
- return -ENOSYS;
-#endif
-
- pagefault_disable();
-
switch (op) {
case FUTEX_OP_SET:
- __futex_atomic_op("mov %1, %4", ret, oldval, uaddr, oparg);
+ __futex_atomic_op("mov %[newval], %[oparg]",
+ ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
- __futex_atomic_op("add %1, %0, %4", ret, oldval, uaddr,
- oparg);
+ __futex_atomic_op("add %[newval], %[oldval], %[oparg]",
+ ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
- __futex_atomic_op("or %1, %0, %4", ret, oldval, uaddr,
- oparg);
+ __futex_atomic_op("or %[newval], %[oldval], %[oparg]",
+ ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
- __futex_atomic_op("and %1, %0, %4", ret, oldval, uaddr,
- ~oparg);
+ __futex_atomic_op("and %[newval], %[oldval], %[oparg]",
+ ret, oldval, uaddr, ~oparg);
break;
case FUTEX_OP_XOR:
- __futex_atomic_op("xor %1, %0, %4", ret, oldval, uaddr,
- oparg);
+ __futex_atomic_op("xor %[newval], %[oldval], %[oparg]",
+ ret, oldval, uaddr, oparg);
break;
default:
ret = -ENOSYS;
}
- pagefault_enable();
-
- if (ret)
- return ret;
+ if (!ret)
+ *oval = oldval;
- switch (cmp) {
- case FUTEX_OP_CMP_EQ: return (oldval == cmparg);
- case FUTEX_OP_CMP_NE: return (oldval != cmparg);
- case FUTEX_OP_CMP_LT: return (oldval < cmparg);
- case FUTEX_OP_CMP_GE: return (oldval >= cmparg);
- case FUTEX_OP_CMP_LE: return (oldval <= cmparg);
- case FUTEX_OP_CMP_GT: return (oldval > cmparg);
- }
-
- return -ENOSYS;
+ return ret;
+#else
+ return futex_atomic_op_inuser_local(op, oparg, oval, uaddr);
+#endif
}
static inline int
futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
u32 oldval, u32 newval)
{
+#if XCHAL_HAVE_S32C1I || XCHAL_HAVE_EXCLUSIVE
+ unsigned long tmp;
int ret = 0;
- u32 prev;
- if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+ if (!access_ok(uaddr, sizeof(u32)))
return -EFAULT;
-#if !XCHAL_HAVE_S32C1I
- return -ENOSYS;
-#endif
-
__asm__ __volatile__ (
" # futex_atomic_cmpxchg_inatomic\n"
- "1: l32i %1, %3, 0\n"
- " mov %0, %5\n"
- " wsr %1, scompare1\n"
- "2: s32c1i %0, %3, 0\n"
- "3:\n"
+#if XCHAL_HAVE_EXCLUSIVE
+ "1: l32ex %[tmp], %[addr]\n"
+ " s32i %[tmp], %[uval], 0\n"
+ " bne %[tmp], %[oldval], 2f\n"
+ " mov %[tmp], %[newval]\n"
+ "3: s32ex %[tmp], %[addr]\n"
+ " getex %[tmp]\n"
+ " beqz %[tmp], 1b\n"
+#elif XCHAL_HAVE_S32C1I
+ " wsr %[oldval], scompare1\n"
+ "1: s32c1i %[newval], %[addr], 0\n"
+ " s32i %[newval], %[uval], 0\n"
+#endif
+ "2:\n"
" .section .fixup,\"ax\"\n"
" .align 4\n"
- "4: .long 3b\n"
- "5: l32r %1, 4b\n"
- " movi %0, %6\n"
- " jx %1\n"
+ " .literal_position\n"
+ "4: movi %[tmp], 2b\n"
+ " movi %[ret], %[fault]\n"
+ " jx %[tmp]\n"
" .previous\n"
" .section __ex_table,\"a\"\n"
- " .long 1b,5b,2b,5b\n"
+ " .long 1b, 4b\n"
+#if XCHAL_HAVE_EXCLUSIVE
+ " .long 3b, 4b\n"
+#endif
" .previous\n"
- : "+r" (ret), "=&r" (prev), "+m" (*uaddr)
- : "r" (uaddr), "r" (oldval), "r" (newval), "I" (-EFAULT)
+ : [ret] "+r" (ret), [newval] "+r" (newval), [tmp] "=&r" (tmp)
+ : [addr] "r" (uaddr), [oldval] "r" (oldval), [uval] "r" (uval),
+ [fault] "I" (-EFAULT)
: "memory");
- *uval = prev;
return ret;
+#else
+ return futex_atomic_cmpxchg_inatomic_local(uval, uaddr, oldval, newval);
+#endif
}
-#endif /* __KERNEL__ */
#endif /* _ASM_XTENSA_FUTEX_H */