[PATCH][RFC] ->mnt_devname is never NULL

[Al Viro <viro@xxxxxxxxxxxxxxxxxx>]

Not since 8f2918898eb5 "new helpers: vfs_create_mount(), fc_mount()"
back in 2018.  Get rid of the dead checks...
    
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
diff --git a/fs/namespace.c b/fs/namespace.c
index d9ca80dcc544..fa17762268f5 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -355,12 +355,13 @@ static struct mount *alloc_vfsmnt(const char *name)
 		if (err)
 			goto out_free_cache;
 
-		if (name) {
+		if (name)
 			mnt->mnt_devname = kstrdup_const(name,
 							 GFP_KERNEL_ACCOUNT);
-			if (!mnt->mnt_devname)
-				goto out_free_id;
-		}
+		else
+			mnt->mnt_devname = "none";
+		if (!mnt->mnt_devname)
+			goto out_free_id;
 
 #ifdef CONFIG_SMP
 		mnt->mnt_pcp = alloc_percpu(struct mnt_pcp);
@@ -1268,7 +1269,7 @@ struct vfsmount *vfs_create_mount(struct fs_context *fc)
 	if (!fc->root)
 		return ERR_PTR(-EINVAL);
 
-	mnt = alloc_vfsmnt(fc->source ?: "none");
+	mnt = alloc_vfsmnt(fc->source);
 	if (!mnt)
 		return ERR_PTR(-ENOMEM);
 
@@ -5491,7 +5492,7 @@ static int statmount_sb_source(struct kstatmount *s, struct seq_file *seq)
 		seq->buf[seq->count] = '\0';
 		seq->count = start;
 		seq_commit(seq, string_unescape_inplace(seq->buf + start, UNESCAPE_OCTAL));
-	} else if (r->mnt_devname) {
+	} else {
 		seq_puts(seq, r->mnt_devname);
 	}
 	return 0;
diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index e133b507ddf3..5c555db68aa2 100644
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -111,7 +111,7 @@ static int show_vfsmnt(struct seq_file *m, struct vfsmount *mnt)
 		if (err)
 			goto out;
 	} else {
-		mangle(m, r->mnt_devname ? r->mnt_devname : "none");
+		mangle(m, r->mnt_devname);
 	}
 	seq_putc(m, ' ');
 	/* mountpoints outside of chroot jail will give SEQ_SKIP on this */
@@ -177,7 +177,7 @@ static int show_mountinfo(struct seq_file *m, struct vfsmount *mnt)
 		if (err)
 			goto out;
 	} else {
-		mangle(m, r->mnt_devname ? r->mnt_devname : "none");
+		mangle(m, r->mnt_devname);
 	}
 	seq_puts(m, sb_rdonly(sb) ? " ro" : " rw");
 	err = show_sb_opts(m, sb);
@@ -199,17 +199,13 @@ static int show_vfsstat(struct seq_file *m, struct vfsmount *mnt)
 	int err;
 
 	/* device */
+	seq_puts(m, "device ");
 	if (sb->s_op->show_devname) {
-		seq_puts(m, "device ");
 		err = sb->s_op->show_devname(m, mnt_path.dentry);
 		if (err)
 			goto out;
 	} else {
-		if (r->mnt_devname) {
-			seq_puts(m, "device ");
-			mangle(m, r->mnt_devname);
-		} else
-			seq_puts(m, "no device");
+		mangle(m, r->mnt_devname);
 	}
 
 	/* mount point */