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>

2 files changed, 12 insertions, 12 deletions

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 9ec313e9f6e1..13454e5fd3fb 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -1006,17 +1006,17 @@ static int fanotify_find_path(int dfd, const char __user *filename,
 		struct fd f = fdget(dfd);
 
 		ret = -EBADF;
-		if (!f.file)
+		if (!fd_file(f))
 			goto out;
 
 		ret = -ENOTDIR;
 		if ((flags & FAN_MARK_ONLYDIR) &&
-		    !(S_ISDIR(file_inode(f.file)->i_mode))) {
+		    !(S_ISDIR(file_inode(fd_file(f))->i_mode))) {
 			fdput(f);
 			goto out;
 		}
 
-		*path = f.file->f_path;
+		*path = fd_file(f)->f_path;
 		path_get(path);
 		fdput(f);
 	} else {
@@ -1753,14 +1753,14 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	}
 
 	f = fdget(fanotify_fd);
-	if (unlikely(!f.file))
+	if (unlikely(!fd_file(f)))
 		return -EBADF;
 
 	/* verify that this is indeed an fanotify instance */
 	ret = -EINVAL;
-	if (unlikely(f.file->f_op != &fanotify_fops))
+	if (unlikely(fd_file(f)->f_op != &fanotify_fops))
 		goto fput_and_out;
-	group = f.file->private_data;
+	group = fd_file(f)->private_data;
 
 	/*
 	 * An unprivileged user is not allowed to setup mount nor filesystem
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 4ffc30606e0b..c7e451d5bd51 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -753,7 +753,7 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 		return -EINVAL;
 
 	f = fdget(fd);
-	if (unlikely(!f.file))
+	if (unlikely(!fd_file(f)))
 		return -EBADF;
 
 	/* IN_MASK_ADD and IN_MASK_CREATE don't make sense together */
@@ -763,7 +763,7 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 	}
 
 	/* verify that this is indeed an inotify instance */
-	if (unlikely(f.file->f_op != &inotify_fops)) {
+	if (unlikely(fd_file(f)->f_op != &inotify_fops)) {
 		ret = -EINVAL;
 		goto fput_and_out;
 	}
@@ -780,7 +780,7 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 
 	/* inode held in place by reference to path; group by fget on fd */
 	inode = path.dentry->d_inode;
-	group = f.file->private_data;
+	group = fd_file(f)->private_data;
 
 	/* create/update an inode mark */
 	ret = inotify_update_watch(group, inode, mask);
@@ -798,14 +798,14 @@ SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd)
 	int ret = -EINVAL;
 
 	f = fdget(fd);
-	if (unlikely(!f.file))
+	if (unlikely(!fd_file(f)))
 		return -EBADF;
 
 	/* verify that this is indeed an inotify instance */
-	if (unlikely(f.file->f_op != &inotify_fops))
+	if (unlikely(fd_file(f)->f_op != &inotify_fops))
 		goto out;
 
-	group = f.file->private_data;
+	group = fd_file(f)->private_data;
 
 	i_mark = inotify_idr_find(group, wd);
 	if (unlikely(!i_mark))