Re: Re: Usage of readb() and friends...

On Tue, 2004-03-02 at 23:15, Geert Uytterhoeven wrote:

On Tue, 2 Mar 2004, Kars de Jong wrote:

quoted

Which reminds me: drivers/video/fbmem.c at least seems to treat the
return value of ioremap() as a virtual address, since it calls
copy_{to,from}_user on it directly...

You're right. And the trouble there is that you can't easily find out which
ioremap() variant was used...

And... it's illegal to call copy_to/from_user on the return of
ioremap anyway. Not only for semantic reasons, but also for practical
reasons, for example, ioremap returns non cacheable space on PPC,
and copy_to/from_user uses "cache hints" to speed up the copy.

Ben.




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