Re: New Mitsumi legacy CD-ROM driver

Rene Herman
2007-05-08T14:27:22Z

On 05/08/2007 03:53 PM, Pekka Enberg wrote:

>> +static int __mitsumi_read_toc(struct mitsumi_cdrom *mcd)
>> +{
>> + int tracks = mcd->header.cdth_trk1 - mcd->header.cdth_trk0 + 1;
>> + int retries;
>> + int err = 0;
>> +
>> + kfree(mcd->toc);
>> +
>> + mcd->toc = kzalloc(tracks * sizeof *mcd->toc, GFP_KERNEL);
>
> Perhaps we should use krealloc() + memset() here?

Earlier I had a patch lined up that checked the previous number of tracks
against the current number and only freed the TOC array when they were not
the same. The majority case is a data CD with one TOC entry meaning we just
reuse the entry. You then have to keep the previous number of tracks though
and it seemed a little pointless so I dropped it.

Another option is using a linked list for the TOC and reusing or allocating
nodes upon reading the actual entry from the Q channel and freeing the rest
when we got them all. Also seemed overly complex and the CDROMREADTOCENTRY
gets slower ;-)

I admit my DOS inspired dislike of realloc() is largely pointless these days
but, err... "E426: tag not found: krealloc". Would you perhaps like the
list? Or the if (tracks != mcd->tracks) thing?

Rene.