[PATCH] allow callers of seq_open do allocation themselves
Allow caller of seq_open() to kmalloc() seq_file + whatever else they
want and set ->private_data to it. seq_open() will then abstain from
doing allocation itself.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 38ef913..7c40570 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -28,13 +28,17 @@
*/
int seq_open(struct file *file, struct seq_operations *op)
{
- struct seq_file *p = kmalloc(sizeof(*p), GFP_KERNEL);
- if (!p)
- return -ENOMEM;
+ struct seq_file *p = file->private_data;
+
+ if (!p) {
+ p = kmalloc(sizeof(*p), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+ file->private_data = p;
+ }
memset(p, 0, sizeof(*p));
sema_init(&p->sem, 1);
p->op = op;
- file->private_data = p;
/*
* Wrappers around seq_open(e.g. swaps_open) need to be