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author | Ingo Molnar <mingo@kernel.org> | 2018-04-05 09:20:34 +0200 |
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committer | Ingo Molnar <mingo@kernel.org> | 2018-04-05 09:20:34 +0200 |
commit | ea2a6af517714c52a1209795a03e863e96b460bb (patch) | |
tree | 3bd443bc9b23ceeaf3743eaf2d6d35ec63c620c9 /arch/nds32/include/asm/futex.h | |
parent | sched/cpufreq/schedutil: Fix error path mutex unlock (diff) | |
parent | Merge branch 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git... (diff) | |
download | linux-ea2a6af517714c52a1209795a03e863e96b460bb.tar.xz linux-ea2a6af517714c52a1209795a03e863e96b460bb.zip |
Merge branch 'linus' into sched/urgent, to pick up fixes and updates
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/nds32/include/asm/futex.h')
-rw-r--r-- | arch/nds32/include/asm/futex.h | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/arch/nds32/include/asm/futex.h b/arch/nds32/include/asm/futex.h new file mode 100644 index 000000000000..eab5e84bd991 --- /dev/null +++ b/arch/nds32/include/asm/futex.h @@ -0,0 +1,103 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2005-2017 Andes Technology Corporation + +#ifndef __NDS32_FUTEX_H__ +#define __NDS32_FUTEX_H__ + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <asm/errno.h> + +#define __futex_atomic_ex_table(err_reg) \ + " .pushsection __ex_table,\"a\"\n" \ + " .align 3\n" \ + " .long 1b, 4f\n" \ + " .long 2b, 4f\n" \ + " .popsection\n" \ + " .pushsection .fixup,\"ax\"\n" \ + "4: move %0, " err_reg "\n" \ + " j 3b\n" \ + " .popsection" + +#define __futex_atomic_op(insn, ret, oldval, tmp, uaddr, oparg) \ + smp_mb(); \ + asm volatile( \ + " movi $ta, #0\n" \ + "1: llw %1, [%2+$ta]\n" \ + " " insn "\n" \ + "2: scw %0, [%2+$ta]\n" \ + " beqz %0, 1b\n" \ + " movi %0, #0\n" \ + "3:\n" \ + __futex_atomic_ex_table("%4") \ + : "=&r" (ret), "=&r" (oldval) \ + : "r" (uaddr), "r" (oparg), "i" (-EFAULT) \ + : "cc", "memory") +static inline int +futex_atomic_cmpxchg_inatomic(u32 * uval, u32 __user * uaddr, + u32 oldval, u32 newval) +{ + int ret = 0; + u32 val, tmp, flags; + + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + + smp_mb(); + asm volatile (" movi $ta, #0\n" + "1: llw %1, [%6 + $ta]\n" + " sub %3, %1, %4\n" + " cmovz %2, %5, %3\n" + " cmovn %2, %1, %3\n" + "2: scw %2, [%6 + $ta]\n" + " beqz %2, 1b\n" + "3:\n " __futex_atomic_ex_table("%7") + :"+&r"(ret), "=&r"(val), "=&r"(tmp), "=&r"(flags) + :"r"(oldval), "r"(newval), "r"(uaddr), "i"(-EFAULT) + :"$ta", "memory"); + smp_mb(); + + *uval = val; + return ret; +} + +static inline int +arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) +{ + int oldval = 0, ret; + + + pagefault_disable(); + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op("move %0, %3", ret, oldval, tmp, uaddr, + oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op("add %0, %1, %3", ret, oldval, tmp, uaddr, + oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op("or %0, %1, %3", ret, oldval, tmp, uaddr, + oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op("and %0, %1, %3", ret, oldval, tmp, uaddr, + ~oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op("xor %0, %1, %3", ret, oldval, tmp, uaddr, + oparg); + break; + default: + ret = -ENOSYS; + } + + pagefault_enable(); + + if (!ret) + *oval = oldval; + + return ret; +} +#endif /* __NDS32_FUTEX_H__ */ |