Re: [PATCH 2.6.24-rc4] proc: Remove/Fix proc generic d_revalidate

Petr Vandrovec
2007-12-10T03:13:29Z

Eric W. Biederman wrote:
> Ultimately to implement /proc perfectly we need an implementation
> of d_revalidate because files and directories can be removed behind
> the back of the VFS, and d_revalidate is the only way we can let
> the VFS know that this has happened.
>
> So until we get a proper test for keeping dentries in the dcache
> fix the current d_revalidate method by completely removing it. This
> returns us to the current status quo.

Hello,
I know that I'm late to the party, but mount points is not only
problem with d_revalidate. With your patch in place module below gets
refcount incremented by two every time I do 'ls -la /proc/fs/vmblock'.

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/proc_fs.h>

static int vmblockinit(void) {
struct proc_dir_entry *controlProcDirEntry;

/* Create /proc/fs/vmblock */
controlProcDirEntry = proc_mkdir("vmblock", proc_root_fs);
if (!controlProcDirEntry) {
printk(KERN_DEBUG "Bad...\n");
return -EINVAL;
}
controlProcDirEntry->owner = THIS_MODULE;
return 0;
}

static void vmblockexit(void) {
remove_proc_entry("vmblock", proc_root_fs);
}

module_init(vmblockinit);
module_exit(vmblockexit);

(code comes from VMware's vmblock module,
http://sourceforge.net/project/showfiles.php?group_id=204462)
Thanks,
Petr