proc: don't detour through seq->private to get the inode

Christoph Hellwig · Christoph Hellwig · commit 04015e3fa235 · 2018-05-16T07:23:35.000+02:00
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
diff --git a/fs/proc/array.c b/fs/proc/array.c
@@ -677,20 +677,22 @@ get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
 
 static int children_seq_show(struct seq_file *seq, void *v)
 {
-	seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(seq->private)));
+	struct inode *inode = file_inode(seq->file);
+
+	seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(inode)));
 	return 0;
 }
 
 static void *children_seq_start(struct seq_file *seq, loff_t *pos)
 {
-	return get_children_pid(seq->private, NULL, *pos);
+	return get_children_pid(file_inode(seq->file), NULL, *pos);
 }
 
 static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	struct pid *pid;
 
-	pid = get_children_pid(seq->private, v, *pos + 1);
+	pid = get_children_pid(file_inode(seq->file), v, *pos + 1);
 	put_pid(v);
 
 	++*pos;
@@ -711,17 +713,7 @@ static const struct seq_operations children_seq_ops = {
 
 static int children_seq_open(struct inode *inode, struct file *file)
 {
-	struct seq_file *m;
-	int ret;
-
-	ret = seq_open(file, &children_seq_ops);
-	if (ret)
-		return ret;
-
-	m = file->private_data;
-	m->private = inode;
-
-	return ret;
+	return seq_open(file, &children_seq_ops);
 }
 
 const struct file_operations proc_tid_children_operations = {

Original file line number	Diff line number	Diff line change
`@@ -677,20 +677,22 @@ get_children_pid(struct inode inode, struct pid pid_prev, loff_t pos)`
`677`	`677`
`678`	`678`	`static int children_seq_show(struct seq_file seq, void v)`
`679`	`679`	`{`
`680`		`- seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(seq->private)));`
	`680`	`+ struct inode *inode = file_inode(seq->file);`
	`681`	`+`
	`682`	`+ seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(inode)));`
`681`	`683`	`return 0;`
`682`	`684`	`}`
`683`	`685`
`684`	`686`	`static void children_seq_start(struct seq_file seq, loff_t *pos)`
`685`	`687`	`{`
`686`		`- return get_children_pid(seq->private, NULL, *pos);`
	`688`	`+ return get_children_pid(file_inode(seq->file), NULL, *pos);`
`687`	`689`	`}`
`688`	`690`
`689`	`691`	`static void children_seq_next(struct seq_file seq, void v, loff_t pos)`
`690`	`692`	`{`
`691`	`693`	`struct pid *pid;`
`692`	`694`
`693`		`- pid = get_children_pid(seq->private, v, *pos + 1);`
	`695`	`+ pid = get_children_pid(file_inode(seq->file), v, *pos + 1);`
`694`	`696`	`put_pid(v);`
`695`	`697`
`696`	`698`	`++*pos;`
`@@ -711,17 +713,7 @@ static const struct seq_operations children_seq_ops = {`
`711`	`713`
`712`	`714`	`static int children_seq_open(struct inode inode, struct file file)`
`713`	`715`	`{`
`714`		`- struct seq_file *m;`
`715`		`- int ret;`
`716`		`-`
`717`		`- ret = seq_open(file, &children_seq_ops);`
`718`		`- if (ret)`
`719`		`- return ret;`
`720`		`-`
`721`		`- m = file->private_data;`
`722`		`- m->private = inode;`
`723`		`-`
`724`		`- return ret;`
	`716`	`+ return seq_open(file, &children_seq_ops);`
`725`	`717`	`}`
`726`	`718`
`727`	`719`	`const struct file_operations proc_tid_children_operations = {`