Re: [OT] Re: keyboard driver of 2.6 kernel

[Roberto Nibali <ratz@drugphish.ch>]

> > I'll let you know if I need it; I reckon it might not be too 
> > difficult to backport it anyway, so I can also do it myself ;).
> I stumbled upon ttyrpld a couple weeks ago and thought it was pretty 
> useful, to keep track of all actions performed on a couple of machines 
> where only the admins have local accounts. Since I'm running a (heavily 
> modified) custom 2.4.22 kernel, I took the version Jan offered for 
> 2.4.29 (in ttyrpld-2.03.5) and synced it up with the work he did on 
> later versions. I think it's identical, functionality wise, to the 
> patch he offered on ttyrpld 2.10. I also massaged it a bit so it would 
> build statically into the kernel (my boxes don't have module support) 
> and to get rid of the extra fluff -- the dependency on moduleparm.h 
> which doesn't exit in 2.4.22, the BSD defines, the 2.6 defines, etc. 
> Also, if built as a module, it'll be called 'rpl' instead of 'rpldev'.

Why?

> I'm running it now on a couple boxes, with the latest userspace bits 
> (libHX 1.74 and ttyrpld 2.10), and It Works For Me (tm). So, with that 
> disclaimer out of the way, here's the patch. It's diffed against my 
> custom 2.4.22 kernel, but should apply fairly well to any 2.4.

Thanks for sharing your work! Comments on the coding style aside (it's 
not exactly winning a beauty contest), one thing I spotted while 
skimming over your patch:

> +static int urpl_open(struct inode *inode, struct file *filp) {
> +    // This one is called when the device node has been opened.
> +    if(inode != NULL) {
> +        inode->i_mtime = CURRENT_TIME;
> +        inode->i_mode &= ~(S_IWUGO | S_IXUGO);
> +    }
> +
> +    /* The RPL device should only be opened once, since otherwise, 
different
> +    packets could go to different readers. */
> +    down(&Open_lock);
> +    if(Open_count) {
> +        up(&Open_lock);
> +        return -EBUSY;
> +    }
> +    ++Open_count;
> +    up(&Open_lock);
> +
> +    down(&Buffer_lock);
> +    Buffer = __vmalloc(Bufsize, GFP_KERNEL | __GFP_HIGHMEM, 
PAGE_KERNEL);
> +    if(Buffer == NULL) {
> +        up(&Buffer_lock);
> +        up(&Open_lock);

This does not seem to be correct. This semaphore has been released 
already and urpl_open is not called under a lock AFAICS.

I'll see if we can fit something like this into the next kernel round 
for our distro. The code needs major cleanup though.

Best regards,
Roberto Nibali, ratz
--
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