sh: Fix up futex implementation.
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>
diff --git a/include/asm-sh/futex.h b/include/asm-sh/futex.h
index 6a332a9..74ed368 100644
--- a/include/asm-sh/futex.h
+++ b/include/asm-sh/futex.h
@@ -1,6 +1,77 @@
-#ifndef _ASM_FUTEX_H
-#define _ASM_FUTEX_H
+#ifndef __ASM_SH_FUTEX_H
+#define __ASM_SH_FUTEX_H
-#include <asm-generic/futex.h>
+#ifdef __KERNEL__
-#endif
+#include <linux/futex.h>
+#include <asm/errno.h>
+#include <asm/uaccess.h>
+
+/* XXX: UP variants, fix for SH-4A and SMP.. */
+#include <asm/futex-irq.h>
+
+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;
+
+ if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+ oparg = 1 << oparg;
+
+ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+ 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(int __user *uaddr, int oldval, int newval)
+{
+ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+ return -EFAULT;
+
+ return atomic_futex_op_cmpxchg_inatomic(uaddr, oldval, newval);
+}
+
+#endif /* __KERNEL__ */
+#endif /* __ASM_SH_FUTEX_H */