tree 9b66a97df10db3d09be94e90b90f1e3b6eaa4934
parent a6030fcc608bd333c80eab3bfc72f63906476c61
author Andrew G. Harvey <agh@cisco.com> 1222211402 +0200
committer Greg Kroah-Hartman <gregkh@suse.de> 1224174294 -0700

UIO: Fix mapping of logical and virtual memory

mmap() doesn't work as expected for UIO_MEM_LOGICAL or UIO_MEM_VIRTUAL
mappings. The offset into the memory needs to be added, otherwise
uio_vma_fault always returns the first page only. Note that for UIO
userspace calls mmap() with offset = N * getpagesize() to access
mapping N. This must be compensated when calculating the offset. A
comment was added to explain this since it is not obvious.

Signed-off-by: Andrew G. Harvey <agh@cisco.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>