introduce fd_file(), convert all accessors to it.

	For any changes of struct fd representation we need to
turn existing accesses to fields into calls of wrappers.
Accesses to struct fd::flags are very few (3 in linux/file.h,
1 in net/socket.c, 3 in fs/overlayfs/file.c and 3 more in
explicit initializers).
	Those can be dealt with in the commit converting to
new layout; accesses to struct fd::file are too many for that.
	This commit converts (almost) all of f.file to
fd_file(f).  It's not entirely mechanical ('file' is used as
a member name more than just in struct fd) and it does not
even attempt to distinguish the uses in pointer context from
those in boolean context; the latter will be eventually turned
into a separate helper (fd_empty()).

	NOTE: mass conversion to fd_empty(), tempting as it
might be, is a bad idea; better do that piecewise in commit
that convert from fdget...() to CLASS(...).

[conflicts in fs/fhandle.c, kernel/bpf/syscall.c, mm/memcontrol.c
caught by git; fs/stat.c one got caught by git grep]
[fs/xattr.c conflict]

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

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/xfs/xfs_exchrange.c b/fs/xfs/xfs_exchrange.c
index c8a655c92c92..9790e0f45d14 100644
--- a/fs/xfs/xfs_exchrange.c
+++ b/fs/xfs/xfs_exchrange.c
@@ -794,9 +794,9 @@ xfs_ioc_exchange_range(
 	fxr.flags		= args.flags;
 
 	file1 = fdget(args.file1_fd);
-	if (!file1.file)
+	if (!fd_file(file1))
 		return -EBADF;
-	fxr.file1 = file1.file;
+	fxr.file1 = fd_file(file1);
 
 	error = xfs_exchange_range(&fxr);
 	fdput(file1);