[PATCH 00/10] IOCHK interface for I/O error handling/detecting

Hidetoshi Seto seto.hidetoshi at jp.fujitsu.com
Fri Jun 10 20:30:24 EST 2005


Matthew Wilcox wrote:
>>Today's patch is 3rd one - iochk_clear/read() interface.
>>- This also adds pair-interface, but not to sandwich only readX().
>>  Depends on platform, starting with ioreadX(), inX(), writeX()
>>  if possible... and so on could be target of error checking.
> 
> It makes sense to sandwich other kinds of device accesses.  I don't
> think the previous clear/read_pci_errors() interface was intended *only*
> to sandwich readX().

At least there was _me_ who actually intended that... :-p
Thank you for being so understanding.

>>- Additionally adds special token - abstract "iocookie" structure
>>  to control/identifies/manage I/Os, by passing it to OS.
>>  Actual type of "iocookie" could be arch-specific. Device drivers
>>  could use the iocookie structure without knowing its detail.
> 
> I'm not sure we need this.  Surely it can be deduced from the pci_dev or
> struct device?

Once I prepared a cookie per a device, added it into pci_dev.
But one of our NIC driver folks pointed out that it was hard to handle
because there could be many contexts/threads riding on one device at same
time. So I reconsidered it and now come to "a cookie per a context" style.

>>            *buf++ = ioread32(dev, ofs);
> 
> You do know that ioread32() doesn't take a pci_dev, right?  I hope you
> weren't counting on that for the rest of your implementation.

Oops. It's just my typo. Please ignore it.

Thanks,
H.Seto




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