From: Ingo Oeser <ioe-lkml@rameria.de>
To: Miklos Szeredi <miklos@szeredi.hu>
Subject: Re: [patch 03/11] fuse: add reference counting to fuse_file
Date: Sat, 4 Aug 2007 13:41:15 +0200
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Hi Miklos,

On Friday 03 August 2007, Miklos Szeredi wrote:
> From: Miklos Szeredi <mszeredi@suse.cz>
> 
> Make lifetime of 'struct fuse_file' independent from 'struct file' by
> adding a reference counter and destructor.

What about using krefs to implement that?

see include/linux/kref.h
and lib/kref.c

Just embed that "struct kref" inside your struct fuse_file

struct fuse_file {
...
	struct kref ref;
...
}

init in struct fuse_file *fuse_file_alloc(void) where you added the counter.
...
kref_init(&ff->ref);
...

and implement the release function like:

static void fuse_file_release(struct kref *ff_ref)
{
	struct fuse_file *ff = container_of(ff_ref, struct fuse_file, ref);
        struct fuse_req *req = ff->reserved_req;
        struct fuse_conn *fc = get_fuse_conn(req->dentry->d_inode);
        request_send_background(fc, req);
        kfree(ff);
}

This will also fix the missing smp_barriers, is very simple, saves code,
makes your life easier and is a well known known kernel infrastructure :-)

BTW: FUSE rocks! :-)

You can add my "Signed-off-by: Ingo Oeser <ioe-lkml@rameria.de>",
if you want to use that suggestion.

Best Regards

Ingo Oeser
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