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authorSamuel Thibault <samuel.thibault@ens-lyon.org>2012-02-19 06:14:24 +0000
committerSamuel Thibault <samuel.thibault@ens-lyon.org>2012-02-19 06:14:24 +0000
commit6fafeb146e9efd59140ea58cebd7dd38ae9a6379 (patch)
tree7db89ba6a28932514b105d620bba4884ec332ec3 /libdde_linux26/contrib/include/linux/err.h
parent38c2c2458e3f4ecb329ff35621806252aac209b9 (diff)
parent8df772b3c665e663f6f9d2a70f9c691590bd3f91 (diff)
Merge branch 'dde' into upstream-merged
Diffstat (limited to 'libdde_linux26/contrib/include/linux/err.h')
-rw-r--r--libdde_linux26/contrib/include/linux/err.h52
1 files changed, 52 insertions, 0 deletions
diff --git a/libdde_linux26/contrib/include/linux/err.h b/libdde_linux26/contrib/include/linux/err.h
new file mode 100644
index 00000000..ec87f314
--- /dev/null
+++ b/libdde_linux26/contrib/include/linux/err.h
@@ -0,0 +1,52 @@
+#ifndef _LINUX_ERR_H
+#define _LINUX_ERR_H
+
+#include <linux/compiler.h>
+
+#include <asm/errno.h>
+
+/*
+ * Kernel pointers have redundant information, so we can use a
+ * scheme where we can return either an error code or a dentry
+ * pointer with the same return value.
+ *
+ * This should be a per-architecture thing, to allow different
+ * error and pointer decisions.
+ */
+#define MAX_ERRNO 4095
+
+#ifndef __ASSEMBLY__
+
+#define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO)
+
+static inline void *ERR_PTR(long error)
+{
+ return (void *) error;
+}
+
+static inline long PTR_ERR(const void *ptr)
+{
+ return (long) ptr;
+}
+
+static inline long IS_ERR(const void *ptr)
+{
+ return IS_ERR_VALUE((unsigned long)ptr);
+}
+
+/**
+ * ERR_CAST - Explicitly cast an error-valued pointer to another pointer type
+ * @ptr: The pointer to cast.
+ *
+ * Explicitly cast an error-valued pointer to another pointer type in such a
+ * way as to make it clear that's what's going on.
+ */
+static inline void *ERR_CAST(const void *ptr)
+{
+ /* cast away the const */
+ return (void *) ptr;
+}
+
+#endif
+
+#endif /* _LINUX_ERR_H */