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, 5 insertions, 5 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 5512cb10fa89..af86e3330594 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2492,25 +2492,25 @@ static const char *path_init(struct nameidata *nd, unsigned flags)
 		struct fd f = fdget_raw(nd->dfd);
 		struct dentry *dentry;
 
-		if (!f.file)
+		if (!fd_file(f))
 			return ERR_PTR(-EBADF);
 
 		if (flags & LOOKUP_LINKAT_EMPTY) {
-			if (f.file->f_cred != current_cred() &&
-			    !ns_capable(f.file->f_cred->user_ns, CAP_DAC_READ_SEARCH)) {
+			if (fd_file(f)->f_cred != current_cred() &&
+			    !ns_capable(fd_file(f)->f_cred->user_ns, CAP_DAC_READ_SEARCH)) {
 				fdput(f);
 				return ERR_PTR(-ENOENT);
 			}
 		}
 
-		dentry = f.file->f_path.dentry;
+		dentry = fd_file(f)->f_path.dentry;
 
 		if (*s && unlikely(!d_can_lookup(dentry))) {
 			fdput(f);
 			return ERR_PTR(-ENOTDIR);
 		}
 
-		nd->path = f.file->f_path;
+		nd->path = fd_file(f)->f_path;
 		if (flags & LOOKUP_RCU) {
 			nd->inode = nd->path.dentry->d_inode;
 			nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq);