linux 2.6.16.38 w/ vs2.0.3-rc1

[linux-2.6.git] / include / asm-xtensa / uaccess.h

diff --git a/include/asm-xtensa/uaccess.h b/include/asm-xtensa/uaccess.h
index 88a64e1..06a22b8 100644 (file)
--- a/include/asm-xtensa/uaccess.h
+++ b/include/asm-xtensa/uaccess.h
@@ -154,6 +154,35 @@
 .Laccess_ok_\@:
        .endm
 
+/*
+ * verify_area determines whether a memory access is allowed.  It's
+ * mostly an unnecessary wrapper for access_ok, but we provide it as a
+ * duplicate of the verify_area() C inline function below.  See the
+ * equivalent C version below for clarity.
+ *
+ * On error, verify_area branches to a label indicated by parameter
+ * <error>.  This implies that the macro falls through to the next
+ * instruction on success.
+ *
+ * Note that we assume success is the common case, and we optimize the
+ * branch fall-through case on success.
+ *
+ * On Entry:
+ *     <aa>    register containing memory address
+ *     <as>    register containing memory size
+ *     <at>    temp register
+ *     <error> label to branch to on error; implies fall-through
+ *             macro on success
+ * On Exit:
+ *     <aa>    preserved
+ *     <as>    preserved
+ *     <at>    destroyed
+ */
+       .macro  verify_area     aa, as, at, sp, error
+       access_ok  \at, \aa, \as, \sp, \error
+       .endm
+
+
 #else /* __ASSEMBLY__ not defined */
 
 #include <linux/sched.h>
@@ -182,6 +211,11 @@
 #define __access_ok(addr,size) (__kernel_ok || __user_ok((addr),(size)))
 #define access_ok(type,addr,size) __access_ok((unsigned long)(addr),(size))
 
+static inline int verify_area(int type, const void * addr, unsigned long size)
+{
+       return access_ok(type,addr,size) ? 0 : -EFAULT;
+}
+
 /*
  * These are the main single-value transfer routines.  They
  * automatically use the right size if we just have the right pointer