Am Donnerstag, 4. August 2005 17:40 schrieb Dave Jones: >On Thu, Aug 04, 2005 at 11:38:30AM +0200, Rolf Eike Beer wrote: > > >+ ulFibreFrame = kmalloc((2048/4), GFP_KERNEL); > > > > The size bug was already found by Dave Jones. This never should be > > written this way (not your fault). The array should have been > > [2048/sizeof(ULONG)]. > >wasteful. We only ever use 2048 bytes of this array, so doubling >its size on 64bit is pointless, unless you make changes later on >in the driver. (Which I think don't make sense, as we just copy >32 64byte chunks).
No, this is how it should have been before. This way it would have been clear
where the magic 4 came from.
>Ermm, actually this looks totally bogus..
>CpqTsGetSFQEntry() ...
>
> if( total_bytes <= 2048 )
> {
> memcpy( ulDestPtr,
> &fcChip->SFQ->QEntry[consumerIndex],
> 64 ); // each SFQ entry is 64 bytes
> ulDestPtr += 16; // advance pointer to next 64 byte block
> }
>
>we're trashing the last 48 bytes of every copy we make.
>Does this driver even work ?
No, ulDestPtr ist ULONG* so we increase it by sizeof(ULONG)*16 which is 64.
This is one of the places I was talking about where people might miss what's
going on. ;) IMHO it makes absolutely no sense to use a ULONG* at this place.
Eike
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