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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/powerpc/include/asm/futex.h | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/include/asm/futex.h')
-rw-r--r-- | arch/powerpc/include/asm/futex.h | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/futex.h b/arch/powerpc/include/asm/futex.h new file mode 100644 index 000000000..b3001f8b2 --- /dev/null +++ b/arch/powerpc/include/asm/futex.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_FUTEX_H +#define _ASM_POWERPC_FUTEX_H + +#ifdef __KERNEL__ + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <asm/errno.h> +#include <asm/synch.h> + +#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ + __asm__ __volatile ( \ + PPC_ATOMIC_ENTRY_BARRIER \ +"1: lwarx %0,0,%2\n" \ + insn \ +"2: stwcx. %1,0,%2\n" \ + "bne- 1b\n" \ + PPC_ATOMIC_EXIT_BARRIER \ + "li %1,0\n" \ +"3: .section .fixup,\"ax\"\n" \ +"4: li %1,%3\n" \ + "b 3b\n" \ + ".previous\n" \ + EX_TABLE(1b, 4b) \ + EX_TABLE(2b, 4b) \ + : "=&r" (oldval), "=&r" (ret) \ + : "b" (uaddr), "i" (-EFAULT), "r" (oparg) \ + : "cr0", "memory") + +static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval, + u32 __user *uaddr) +{ + int oldval = 0, ret; + + if (!user_access_begin(uaddr, sizeof(u32))) + return -EFAULT; + + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op("mr %1,%4\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op("add %1,%0,%4\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op("or %1,%0,%4\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op("andc %1,%0,%4\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op("xor %1,%0,%4\n", ret, oldval, uaddr, oparg); + break; + default: + ret = -ENOSYS; + } + user_access_end(); + + *oval = oldval; + + return ret; +} + +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + int ret = 0; + u32 prev; + + if (!user_access_begin(uaddr, sizeof(u32))) + return -EFAULT; + + __asm__ __volatile__ ( + PPC_ATOMIC_ENTRY_BARRIER +"1: lwarx %1,0,%3 # futex_atomic_cmpxchg_inatomic\n\ + cmpw 0,%1,%4\n\ + bne- 3f\n" +"2: stwcx. %5,0,%3\n\ + bne- 1b\n" + PPC_ATOMIC_EXIT_BARRIER +"3: .section .fixup,\"ax\"\n\ +4: li %0,%6\n\ + b 3b\n\ + .previous\n" + EX_TABLE(1b, 4b) + EX_TABLE(2b, 4b) + : "+r" (ret), "=&r" (prev), "+m" (*uaddr) + : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT) + : "cc", "memory"); + + user_access_end(); + + *uval = prev; + + return ret; +} + +#endif /* __KERNEL__ */ +#endif /* _ASM_POWERPC_FUTEX_H */ |