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fc1d4c9c37
SH is able to support a complete futex implementation on UP by way of gUSA. However, IRQ toggling must be done for the old CPUs that don't have movli.l/movco.l (LL/SC) instructions. Provide a default implementation that does this, so it's possible to optimize for newer CPUs. Follows the same scheme as the current asm-sh/atomic-*.h headers. Signed-off-by: Kaz Kojima <kkojima@rr.iij4u.or.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
78 lines
1.8 KiB
C
78 lines
1.8 KiB
C
#ifndef __ASM_SH_FUTEX_H
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#define __ASM_SH_FUTEX_H
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#ifdef __KERNEL__
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#include <linux/futex.h>
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#include <asm/errno.h>
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#include <asm/uaccess.h>
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/* XXX: UP variants, fix for SH-4A and SMP.. */
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#include <asm/futex-irq.h>
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static inline int futex_atomic_op_inuser(int encoded_op, int __user *uaddr)
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{
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int op = (encoded_op >> 28) & 7;
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int cmp = (encoded_op >> 24) & 15;
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int oparg = (encoded_op << 8) >> 20;
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int cmparg = (encoded_op << 20) >> 20;
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int oldval = 0, ret;
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if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
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oparg = 1 << oparg;
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if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
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return -EFAULT;
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pagefault_disable();
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switch (op) {
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case FUTEX_OP_SET:
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ret = atomic_futex_op_xchg_set(oparg, uaddr, &oldval);
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break;
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case FUTEX_OP_ADD:
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ret = atomic_futex_op_xchg_add(oparg, uaddr, &oldval);
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break;
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case FUTEX_OP_OR:
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ret = atomic_futex_op_xchg_or(oparg, uaddr, &oldval);
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break;
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case FUTEX_OP_ANDN:
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ret = atomic_futex_op_xchg_and(~oparg, uaddr, &oldval);
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break;
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case FUTEX_OP_XOR:
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ret = atomic_futex_op_xchg_xor(oparg, uaddr, &oldval);
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break;
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default:
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ret = -ENOSYS;
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break;
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}
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pagefault_enable();
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if (!ret) {
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switch (cmp) {
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case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
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case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
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case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
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case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
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case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
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case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
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default: ret = -ENOSYS;
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}
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}
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return ret;
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}
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static inline int
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futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
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{
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if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
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return -EFAULT;
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return atomic_futex_op_cmpxchg_inatomic(uaddr, oldval, newval);
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}
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#endif /* __KERNEL__ */
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#endif /* __ASM_SH_FUTEX_H */
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