/** * \file futex.h * Licence details are found in the file LICENSE. * * \brief * Futex adaptation to McKernel * * \author Balazs Gerofi \par * Copyright (C) 2012 RIKEN AICS * * * HISTORY: * */ #ifndef _FUTEX_H #define _FUTEX_H /** \name Futex Commands * @{ */ #define FUTEX_WAIT 0 #define FUTEX_WAKE 1 #define FUTEX_FD 2 #define FUTEX_REQUEUE 3 #define FUTEX_CMP_REQUEUE 4 #define FUTEX_WAKE_OP 5 #define FUTEX_LOCK_PI 6 #define FUTEX_UNLOCK_PI 7 #define FUTEX_TRYLOCK_PI 8 #define FUTEX_WAIT_BITSET 9 #define FUTEX_WAKE_BITSET 10 #define FUTEX_WAIT_REQUEUE_PI 11 #define FUTEX_CMP_REQUEUE_PI 12 // @} #define FUTEX_PRIVATE_FLAG 128 #define FUTEX_CLOCK_REALTIME 256 #define FUTEX_CMD_MASK ~(FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME) #define FUTEX_WAIT_PRIVATE (FUTEX_WAIT | FUTEX_PRIVATE_FLAG) #define FUTEX_WAKE_PRIVATE (FUTEX_WAKE | FUTEX_PRIVATE_FLAG) #define FUTEX_REQUEUE_PRIVATE (FUTEX_REQUEUE | FUTEX_PRIVATE_FLAG) #define FUTEX_CMP_REQUEUE_PRIVATE (FUTEX_CMP_REQUEUE | FUTEX_PRIVATE_FLAG) #define FUTEX_WAKE_OP_PRIVATE (FUTEX_WAKE_OP | FUTEX_PRIVATE_FLAG) #define FUTEX_LOCK_PI_PRIVATE (FUTEX_LOCK_PI | FUTEX_PRIVATE_FLAG) #define FUTEX_UNLOCK_PI_PRIVATE (FUTEX_UNLOCK_PI | FUTEX_PRIVATE_FLAG) #define FUTEX_TRYLOCK_PI_PRIVATE (FUTEX_TRYLOCK_PI | FUTEX_PRIVATE_FLAG) #define FUTEX_WAIT_BITSET_PRIVATE (FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG) #define FUTEX_WAKE_BITSET_PRIVATE (FUTEX_WAKE_BITSET | FUTEX_PRIVATE_FLAG) #define FUTEX_WAIT_REQUEUE_PI_PRIVATE (FUTEX_WAIT_REQUEUE_PI | \ FUTEX_PRIVATE_FLAG) #define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \ FUTEX_PRIVATE_FLAG) /** \name Futex Operations, used for FUTEX_WAKE_OP * @{ */ #define FUTEX_OP_SET 0 /* *(int *)UADDR2 = OPARG; */ #define FUTEX_OP_ADD 1 /* *(int *)UADDR2 += OPARG; */ #define FUTEX_OP_OR 2 /* *(int *)UADDR2 |= OPARG; */ #define FUTEX_OP_ANDN 3 /* *(int *)UADDR2 &= ~OPARG; */ #define FUTEX_OP_XOR 4 /* *(int *)UADDR2 ^= OPARG; */ #define FUTEX_OP_OPARG_SHIFT 8 /* Use (1 << OPARG) instead of OPARG. */ #define FUTEX_OP_CMP_EQ 0 /* if (oldval == CMPARG) wake */ #define FUTEX_OP_CMP_NE 1 /* if (oldval != CMPARG) wake */ #define FUTEX_OP_CMP_LT 2 /* if (oldval < CMPARG) wake */ #define FUTEX_OP_CMP_LE 3 /* if (oldval <= CMPARG) wake */ #define FUTEX_OP_CMP_GT 4 /* if (oldval > CMPARG) wake */ #define FUTEX_OP_CMP_GE 5 /* if (oldval >= CMPARG) wake */ // @} /* FUTEX_WAKE_OP will perform atomically int oldval = *(int *)UADDR2; *(int *)UADDR2 = oldval OP OPARG; if (oldval CMP CMPARG) wake UADDR2; */ #define FUTEX_OP(op, oparg, cmp, cmparg) \ (((op & 0xf) << 28) | ((cmp & 0xf) << 24) \ | ((oparg & 0xfff) << 12) | (cmparg & 0xfff)) /* * bitset with all bits set for the FUTEX_xxx_BITSET OPs to request a * match of any bit. */ #define FUTEX_BITSET_MATCH_ANY 0xffffffff #ifdef __KERNEL__ #include #include #include #include #ifndef _ASM_X86_FUTEX_H #define _ASM_X86_FUTEX_H #ifdef __KERNEL__ /* We don't deal with uaccess at the moment, because x86 can access * userspace directly, we rely on glibc and the app developers. */ #ifdef __UACCESS__ #include #endif #include #include #define __user #if 0 #include #include #endif #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \ asm volatile("1:\t" insn "\n" \ "2:\t.section .fixup,\"ax\"\n" \ "3:\tmov\t%3, %1\n" \ "\tjmp\t2b\n" \ "\t.previous\n" \ _ASM_EXTABLE(1b, 3b) \ : "=r" (oldval), "=r" (ret), "+m" (*uaddr) \ : "i" (-EFAULT), "0" (oparg), "1" (0)) #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \ asm volatile("1:\tmovl %2, %0\n" \ "\tmovl\t%0, %3\n" \ "\t" insn "\n" \ "2:\tlock; cmpxchgl %3, %2\n" \ "\tjnz\t1b\n" \ "3:\t.section .fixup,\"ax\"\n" \ "4:\tmov\t%5, %1\n" \ "\tjmp\t3b\n" \ "\t.previous\n" \ _ASM_EXTABLE(1b, 4b) \ _ASM_EXTABLE(2b, 4b) \ : "=&a" (oldval), "=&r" (ret), \ "+m" (*uaddr), "=&r" (tem) \ : "r" (oparg), "i" (-EFAULT), "1" (0)) static inline int futex_atomic_op_inuser(int encoded_op, int __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, tem; if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) oparg = 1 << oparg; #ifdef __UACCESS__ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int))) return -EFAULT; #endif switch (op) { case FUTEX_OP_SET: __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg); break; case FUTEX_OP_ADD: __futex_atomic_op1("lock; xaddl %0, %2", ret, oldval, uaddr, oparg); break; case FUTEX_OP_OR: __futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg); break; case FUTEX_OP_ANDN: __futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg); break; case FUTEX_OP_XOR: __futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr, oparg); break; default: ret = -ENOSYS; } 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(int __user *uaddr, int oldval, int newval) { #ifdef __UACCESS__ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int))) return -EFAULT; #endif asm volatile("1:\tlock; cmpxchgl %3, %1\n" "2:\t.section .fixup, \"ax\"\n" "3:\tmov %2, %0\n" "\tjmp 2b\n" "\t.previous\n" _ASM_EXTABLE(1b, 3b) : "=a" (oldval), "+m" (*uaddr) : "i" (-EFAULT), "r" (newval), "0" (oldval) : "memory" ); return oldval; } #endif // __KERNEL__ #endif // _ASM_X86_FUTEX_H #define FUTEX_HASHBITS 8 /* 256 entries in each futex hash tbl */ #define FUT_OFF_INODE 1 /* We set bit 0 if key has a reference on inode */ #define FUT_OFF_MMSHARED 2 /* We set bit 1 if key has a reference on mm */ struct process_vm; union futex_key { #if 0 struct { unsigned long pgoff; struct inode *inode; int offset; } shared; #endif struct { unsigned long address; struct process_vm *mm; int offset; } private; struct { unsigned long word; void *ptr; int offset; } both; }; #define FUTEX_KEY_INIT (union futex_key) { .both = { .ptr = NULL } } extern int futex_init(void); extern int futex( uint32_t __user * uaddr, int op, uint32_t val, uint64_t timeout, uint32_t __user * uaddr2, uint32_t val2, uint32_t val3 ); #endif #endif