Re: [Linux-fbdev-devel] vga256fb

[antirez <an...@in...>]

On Mon, May 14, 2001 at 01:08:32PM +0200, Geert Uytterhoeven wrote:
> On Mon, 14 May 2001, Petr Vandrovec wrote:
> > On 14 May 01 at 11:31, antirez wrote:
> > > user select an unchained mode the first time. While the linear emulation
> > > task is stopped once you return to a linear mode, the memory will
> > > never be freed (it may be in use by another console, also vmalloc()/vfree()
> > > 360*480 bytes every time a user enter/leave a unchained mode seems bad).
> > 
> > Linear emulation cannot work for fbtv! Make sure that running fbtv on such
> > device will not overwrite innocent part of kernel ;-)
> 
> Does user space mmap() works on a vmalloc()'ed frame buffer?

Yep, see my implementation. You can just put the code in the
linux's virtual framebuffer implementation, that's broken.

I did it in two ways: with the nopage method of vma (I vote for this)
and remap(ing)_page_range() every physical page of
the vmalloc()ed memory.

My driver is using the nopage method, that's IMHO the better way
to do it.

For this reasons I guess my driver will work with all the
userspace applications around. *not only* as graphic console.

antirez

-- 
Salvatore Sanfilippo <an...@in...>
http://www.kyuzz.org/antirez
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