add struct fd constructors, get rid of __to_fd()

	Make __fdget() et.al. return struct fd directly.
New helpers: BORROWED_FD(file) and CLONED_FD(file), for
borrowed and cloned file references resp.

	NOTE: this might need tuning; in particular, inline on
__fget_light() is there to keep the code generation same as
before - we probably want to keep it inlined in fdget() et.al.
(especially so in fdget_pos()), but that needs profiling.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 11 insertions, 22 deletions

diff --git a/include/linux/file.h b/include/linux/file.h
index eb28469b1c16..aab1caff6713 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -53,6 +53,14 @@ static inline bool fd_empty(struct fd f)
 }
 
 #define EMPTY_FD (struct fd){0}
+static inline struct fd BORROWED_FD(struct file *f)
+{
+	return (struct fd){(unsigned long)f};
+}
+static inline struct fd CLONED_FD(struct file *f)
+{
+	return (struct fd){(unsigned long)f | FDPUT_FPUT};
+}
 
 static inline void fdput(struct fd fd)
 {
@@ -63,30 +71,11 @@ static inline void fdput(struct fd fd)
 extern struct file *fget(unsigned int fd);
 extern struct file *fget_raw(unsigned int fd);
 extern struct file *fget_task(struct task_struct *task, unsigned int fd);
-extern unsigned long __fdget(unsigned int fd);
-extern unsigned long __fdget_raw(unsigned int fd);
-extern unsigned long __fdget_pos(unsigned int fd);
 extern void __f_unlock_pos(struct file *);
 
-static inline struct fd __to_fd(unsigned long v)
-{
-	return (struct fd){v};
-}
-
-static inline struct fd fdget(unsigned int fd)
-{
-	return __to_fd(__fdget(fd));
-}
-
-static inline struct fd fdget_raw(unsigned int fd)
-{
-	return __to_fd(__fdget_raw(fd));
-}
-
-static inline struct fd fdget_pos(int fd)
-{
-	return __to_fd(__fdget_pos(fd));
-}
+struct fd fdget(unsigned int fd);
+struct fd fdget_raw(unsigned int fd);
+struct fd fdget_pos(unsigned int fd);
 
 static inline void fdput_pos(struct fd f)
 {