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Diffstat (limited to 'arch/parisc/include/asm/futex.h')
-rw-r--r--arch/parisc/include/asm/futex.h77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/futex.h b/arch/parisc/include/asm/futex.h
new file mode 100644
index 000000000000..0c705c3a55ef
--- /dev/null
+++ b/arch/parisc/include/asm/futex.h
@@ -0,0 +1,77 @@
+#ifndef _ASM_PARISC_FUTEX_H
+#define _ASM_PARISC_FUTEX_H
+
+#ifdef __KERNEL__
+
+#include <linux/futex.h>
+#include <linux/uaccess.h>
+#include <asm/errno.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:
+ case FUTEX_OP_ADD:
+ case FUTEX_OP_OR:
+ case FUTEX_OP_ANDN:
+ case FUTEX_OP_XOR:
+ default:
+ ret = -ENOSYS;
+ }
+
+ 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;
+}
+
+/* Non-atomic version */
+static inline int
+futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
+{
+ int err = 0;
+ int uval;
+
+ /* futex.c wants to do a cmpxchg_inatomic on kernel NULL, which is
+ * our gateway page, and causes no end of trouble...
+ */
+ if (segment_eq(KERNEL_DS, get_fs()) && !uaddr)
+ return -EFAULT;
+
+ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+ return -EFAULT;
+
+ err = get_user(uval, uaddr);
+ if (err) return -EFAULT;
+ if (uval == oldval)
+ err = put_user(newval, uaddr);
+ if (err) return -EFAULT;
+ return uval;
+}
+
+#endif /*__KERNEL__*/
+#endif /*_ASM_PARISC_FUTEX_H*/