On Fri, Dec 21 2007, Adrian McMenamin wrote:
> On 20/12/2007, Adrian McMenamin <[EMAIL PROTECTED]> wrote:
> > This patch adds support for the CD Rom device (called a "GD Rom") on
> > the SEGA Dreamcast.This device has a command block similar to a
> > standard ATA-3 device, though implements Sega's proprietary packet
> > interface - the so-called "Sega Packet Interface".
> >
>
> Fairly typically, I noticed I had chopped the final line from the
> patch as soon as I had sent it.
>
> I've also fixed a small difference in the Kconfig
You should properly protect gdrom_deferred, the locking is not clear
there. In gdrom_readdisk_dma() I would do:
static void gdrom_readdisk_dma(struct work_struct *work)
{
...
read_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
if (!read_command)
probably just defer the work to some time later
spin_lock(&gdrom_lock);
while (!list_empty(&gdrom_deferred)) {
req = list_entry(gdrom_deferred.next, struct request,
queuelist);
list_del_init(&req->queuelist);
spin_unlock(&gdrom_lock);
...
spin_lock(&gdrom_lock);
};
kfree(read_command);
}
That's a lot more obvious imho and doesn't suffer from potential races
or list reordering. Your read_command allocation and free for every
command also seems pretty pointless, so move that outside the loop.
What is pages doing in gdrom_request()?
Your design is also heavily geared towards there just being a single
CDROM, I'm assuming this wont be a problem given your hw (it sets a bad
example for others to follow though, lots of violations against normal
programming practice for multiple devices and smp).
--
Jens Axboe
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