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>

3 files changed, 18 insertions, 18 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);
diff --git a/fs/xfs/xfs_handle.c b/fs/xfs/xfs_handle.c
index cf5acbd3c7ca..7bcc4f519cb8 100644
--- a/fs/xfs/xfs_handle.c
+++ b/fs/xfs/xfs_handle.c
@@ -92,9 +92,9 @@ xfs_find_handle(
 
 	if (cmd == XFS_IOC_FD_TO_HANDLE) {
 		f = fdget(hreq->fd);
-		if (!f.file)
+		if (!fd_file(f))
 			return -EBADF;
-		inode = file_inode(f.file);
+		inode = file_inode(fd_file(f));
 	} else {
 		error = user_path_at(AT_FDCWD, hreq->path, 0, &path);
 		if (error)
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 4e933db75b12..95641817370b 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1005,33 +1005,33 @@ xfs_ioc_swapext(
 
 	/* Pull information for the target fd */
 	f = fdget((int)sxp->sx_fdtarget);
-	if (!f.file) {
+	if (!fd_file(f)) {
 		error = -EINVAL;
 		goto out;
 	}
 
-	if (!(f.file->f_mode & FMODE_WRITE) ||
-	    !(f.file->f_mode & FMODE_READ) ||
-	    (f.file->f_flags & O_APPEND)) {
+	if (!(fd_file(f)->f_mode & FMODE_WRITE) ||
+	    !(fd_file(f)->f_mode & FMODE_READ) ||
+	    (fd_file(f)->f_flags & O_APPEND)) {
 		error = -EBADF;
 		goto out_put_file;
 	}
 
 	tmp = fdget((int)sxp->sx_fdtmp);
-	if (!tmp.file) {
+	if (!fd_file(tmp)) {
 		error = -EINVAL;
 		goto out_put_file;
 	}
 
-	if (!(tmp.file->f_mode & FMODE_WRITE) ||
-	    !(tmp.file->f_mode & FMODE_READ) ||
-	    (tmp.file->f_flags & O_APPEND)) {
+	if (!(fd_file(tmp)->f_mode & FMODE_WRITE) ||
+	    !(fd_file(tmp)->f_mode & FMODE_READ) ||
+	    (fd_file(tmp)->f_flags & O_APPEND)) {
 		error = -EBADF;
 		goto out_put_tmp_file;
 	}
 
-	if (IS_SWAPFILE(file_inode(f.file)) ||
-	    IS_SWAPFILE(file_inode(tmp.file))) {
+	if (IS_SWAPFILE(file_inode(fd_file(f))) ||
+	    IS_SWAPFILE(file_inode(fd_file(tmp)))) {
 		error = -EINVAL;
 		goto out_put_tmp_file;
 	}
@@ -1041,14 +1041,14 @@ xfs_ioc_swapext(
 	 * before we cast and access them as XFS structures as we have no
 	 * control over what the user passes us here.
 	 */
-	if (f.file->f_op != &xfs_file_operations ||
-	    tmp.file->f_op != &xfs_file_operations) {
+	if (fd_file(f)->f_op != &xfs_file_operations ||
+	    fd_file(tmp)->f_op != &xfs_file_operations) {
 		error = -EINVAL;
 		goto out_put_tmp_file;
 	}
 
-	ip = XFS_I(file_inode(f.file));
-	tip = XFS_I(file_inode(tmp.file));
+	ip = XFS_I(file_inode(fd_file(f)));
+	tip = XFS_I(file_inode(fd_file(tmp)));
 
 	if (ip->i_mount != tip->i_mount) {
 		error = -EINVAL;