Hi,
Timur Tabi wrote:
> I mark the page as reserved when I ioremap() it. However, if I leave it marked
> reserved, then iounmap() will not unmap it. If I mark it "unreserved" (i.e.
> reset the reserved bit), then iounmap will unmap it, but it will decrement the
> page counter to -1 and the whole system will crash soon thereafter.
>
> I've been asking about this problem for months, but no one has bothered to help
> me out.
The order is important:
get_free_page();
set_bit(PG_reserved, &page->flags);
ioremap();
...
iounmap();
clear_bit(PG_reserved, &page->flags);
free_page();
Alternatively something like this should also be possible:
get_free_page();
ioremap();
...
iounmap();
nopage() {
...
atomic_inc(&page->count);
return page;
}
But I never tried this version, so I can't guarantee anything. :)
bye, Roman
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This archive was generated by hypermail 2b29 : Wed Jan 31 2001 - 21:00:22 EST