Implement pcim_iounmap_regions() - the opposite of
pcim_iomap_regions().
Signed-off-by: NTejun heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

It appears that the pcim_iomap_regions() function doesn't get the error
handling right. It BUGs early at boot with a backtrace along the lines of:

ahci_init
pci_register_driver
driver_register
[...]
ahci_init_one
pcim_iomap_region
pcim_iounmap

The following patch allows me to boot. Only the if(mask..) continue;
part fixes the problem actually, the gotos where changed so that we
don't try to unmap something we couldn't map anyway.
Signed-off-by: NFrederik Deweerdt <frederik.deweerdt@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* Split the implementation-agnostic stuff in separate files.
* Make sure that targets using non-default request_irq() pull
  kernel/irq/devres.o
* Introduce new symbols (HAS_IOPORT and HAS_IOMEM) defaulting to positive;
  allow architectures to turn them off (we needed these symbols anyway for
  dependencies of quite a few drivers).
* protect the ioport-related parts of lib/devres.o with CONFIG_HAS_IOPORT.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>