1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_S390_FUTEX_H 3 #define _ASM_S390_FUTEX_H 4 5 #include <linux/uaccess.h> 6 #include <linux/futex.h> 7 #include <asm/mmu_context.h> 8 #include <asm/errno.h> 9 10 #define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \ 11 asm volatile( \ 12 " sacf 256\n" \ 13 "0: l %1,0(%6)\n" \ 14 "1:"insn \ 15 "2: cs %1,%2,0(%6)\n" \ 16 "3: jl 1b\n" \ 17 " lhi %0,0\n" \ 18 "4: sacf 768\n" \ 19 EX_TABLE(0b,4b) EX_TABLE(2b,4b) EX_TABLE(3b,4b) \ 20 : "=d" (ret), "=&d" (oldval), "=&d" (newval), \ 21 "=m" (*uaddr) \ 22 : "0" (-EFAULT), "d" (oparg), "a" (uaddr), \ 23 "m" (*uaddr) : "cc"); 24 25 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval, 26 u32 __user *uaddr) 27 { 28 int oldval = 0, newval, ret; 29 mm_segment_t old_fs; 30 31 old_fs = enable_sacf_uaccess(); 32 switch (op) { 33 case FUTEX_OP_SET: 34 __futex_atomic_op("lr %2,%5\n", 35 ret, oldval, newval, uaddr, oparg); 36 break; 37 case FUTEX_OP_ADD: 38 __futex_atomic_op("lr %2,%1\nar %2,%5\n", 39 ret, oldval, newval, uaddr, oparg); 40 break; 41 case FUTEX_OP_OR: 42 __futex_atomic_op("lr %2,%1\nor %2,%5\n", 43 ret, oldval, newval, uaddr, oparg); 44 break; 45 case FUTEX_OP_ANDN: 46 __futex_atomic_op("lr %2,%1\nnr %2,%5\n", 47 ret, oldval, newval, uaddr, oparg); 48 break; 49 case FUTEX_OP_XOR: 50 __futex_atomic_op("lr %2,%1\nxr %2,%5\n", 51 ret, oldval, newval, uaddr, oparg); 52 break; 53 default: 54 ret = -ENOSYS; 55 } 56 disable_sacf_uaccess(old_fs); 57 58 if (!ret) 59 *oval = oldval; 60 61 return ret; 62 } 63 64 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 65 u32 oldval, u32 newval) 66 { 67 mm_segment_t old_fs; 68 int ret; 69 70 old_fs = enable_sacf_uaccess(); 71 asm volatile( 72 " sacf 256\n" 73 "0: cs %1,%4,0(%5)\n" 74 "1: la %0,0\n" 75 "2: sacf 768\n" 76 EX_TABLE(0b,2b) EX_TABLE(1b,2b) 77 : "=d" (ret), "+d" (oldval), "=m" (*uaddr) 78 : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr) 79 : "cc", "memory"); 80 disable_sacf_uaccess(old_fs); 81 *uval = oldval; 82 return ret; 83 } 84 85 #endif /* _ASM_S390_FUTEX_H */ 86