This patch introduces the futex operation. Signed-off-by: Ley Foon Tan <lftan@xxxxxxxxxx> --- arch/nios2/include/asm/futex-irq.h | 130 +++++++++++++++++++++++++++++++++++++ arch/nios2/include/asm/futex.h | 110 +++++++++++++++++++++++++++++++ 2 files changed, 240 insertions(+) create mode 100644 arch/nios2/include/asm/futex-irq.h create mode 100644 arch/nios2/include/asm/futex.h diff --git a/arch/nios2/include/asm/futex-irq.h b/arch/nios2/include/asm/futex-irq.h new file mode 100644 index 0000000..ade9296 --- /dev/null +++ b/arch/nios2/include/asm/futex-irq.h @@ -0,0 +1,130 @@ +/* + * Copyright (C) 2013 Altera Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Based on asm/futex.h from sh platform. + * + */ + +#ifndef __ASM_NIOS2_FUTEX_IRQ_H +#define __ASM_NIOS2_FUTEX_IRQ_H + + +static inline int atomic_futex_op_xchg_set(int oparg, u32 __user *uaddr, + int *oldval) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + + ret = get_user(*oldval, uaddr); + if (!ret) + ret = put_user(oparg, uaddr); + + local_irq_restore(flags); + + return ret; +} + +static inline int atomic_futex_op_xchg_add(int oparg, u32 __user *uaddr, + int *oldval) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + + ret = get_user(*oldval, uaddr); + if (!ret) + ret = put_user(*oldval + oparg, uaddr); + + local_irq_restore(flags); + + return ret; +} + +static inline int atomic_futex_op_xchg_or(int oparg, u32 __user *uaddr, + int *oldval) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + + ret = get_user(*oldval, uaddr); + if (!ret) + ret = put_user(*oldval | oparg, uaddr); + + local_irq_restore(flags); + + return ret; +} + +static inline int atomic_futex_op_xchg_and(int oparg, u32 __user *uaddr, + int *oldval) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + + ret = get_user(*oldval, uaddr); + if (!ret) + ret = put_user(*oldval & oparg, uaddr); + + local_irq_restore(flags); + + return ret; +} + +static inline int atomic_futex_op_xchg_xor(int oparg, u32 __user *uaddr, + int *oldval) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + + ret = get_user(*oldval, uaddr); + if (!ret) + ret = put_user(*oldval ^ oparg, uaddr); + + local_irq_restore(flags); + + return ret; +} + +static inline int atomic_futex_op_cmpxchg_inatomic(u32 *uval, + u32 __user *uaddr, + u32 oldval, u32 newval) +{ + unsigned long flags; + int ret; + u32 prev = 0; + + local_irq_save(flags); + + ret = get_user(prev, uaddr); + if (!ret && oldval == prev) + ret = put_user(newval, uaddr); + + local_irq_restore(flags); + + *uval = prev; + return ret; +} + +#endif /* __ASM_NIOS2_FUTEX_IRQ_H */ diff --git a/arch/nios2/include/asm/futex.h b/arch/nios2/include/asm/futex.h new file mode 100644 index 0000000..52b2fa9 --- /dev/null +++ b/arch/nios2/include/asm/futex.h @@ -0,0 +1,110 @@ +/* + * Copyright (C) 2013 Altera Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Based on asm/futex.h from sh platform. + * + */ + +#ifndef __ASM_NIOS2_FUTEX_H +#define __ASM_NIOS2_FUTEX_H + +#ifdef __KERNEL__ + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <linux/errno.h> + +#include <asm/futex-irq.h> + +static inline int futex_atomic_op_inuser(int encoded_op, 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; + int oldval = 0, ret; + + if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) + oparg = 1 << oparg; + + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + + pagefault_disable(); + + switch (op) { + case FUTEX_OP_SET: + ret = atomic_futex_op_xchg_set(oparg, uaddr, &oldval); + break; + case FUTEX_OP_ADD: + ret = atomic_futex_op_xchg_add(oparg, uaddr, &oldval); + break; + case FUTEX_OP_OR: + ret = atomic_futex_op_xchg_or(oparg, uaddr, &oldval); + break; + case FUTEX_OP_ANDN: + ret = atomic_futex_op_xchg_and(~oparg, uaddr, &oldval); + break; + case FUTEX_OP_XOR: + ret = atomic_futex_op_xchg_xor(oparg, uaddr, &oldval); + break; + default: + ret = -ENOSYS; + break; + } + + pagefault_enable(); + + 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(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + + return atomic_futex_op_cmpxchg_inatomic(uval, uaddr, oldval, newval); +} + +#endif /* __KERNEL__ */ +#endif /* __ASM_NIOS2_FUTEX_H */ -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
