[PARISC] Implement futex_atomic_cmpxchg_inatomic
authorCarlos O'Donell <carlos@systemhalted.org>
Thu, 7 Sep 2006 17:05:17 +0000 (13:05 -0400)
committerMatthew Wilcox <willy@parisc-linux.org>
Wed, 4 Oct 2006 12:47:36 +0000 (06:47 -0600)
Implement trivial futex_atomic_cmpxchg_inatomic for testing.

Signed-off-by: Carlos O'Donell <carlos@systemhalted.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
include/asm-parisc/futex.h

index 6a332a9f099c2eafbf78ee5f79056a349d41a775..d84bbb283fd17c7a8e9fb92d4a30a660efe86263 100644 (file)
@@ -1,6 +1,71 @@
-#ifndef _ASM_FUTEX_H
-#define _ASM_FUTEX_H
+#ifndef _ASM_PARISC_FUTEX_H
+#define _ASM_PARISC_FUTEX_H
 
-#include <asm-generic/futex.h>
+#ifdef __KERNEL__
 
+#include <linux/futex.h>
+#include <asm/errno.h>
+#include <asm/uaccess.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;
+
+       inc_preempt_count();
+
+       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;
+       }
+
+       dec_preempt_count();
+
+       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;
+
+       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
 #endif