Messages in this thread | | | Subject | Re: [PATCH] uio: Support 36-bit physical addresses on 32-bit systems | From | Kumar Gala <> | Date | Mon, 17 Oct 2011 11:00:55 -0500 |
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On Oct 14, 2011, at 1:31 PM, Hans J. Koch wrote:
> On Thu, Oct 13, 2011 at 10:50:58AM -0500, Kumar Gala wrote: >> From: Kai Jiang <Kai.Jiang@freescale.com> >> >> To support >32-bit physical addresses for UIO_MEM_PHYS type we need to >> extend the width of 'addr' in struct uio_mem. Numerous platforms like >> embedded PPC, ARM, and X86 have support for systems with larger physical >> address than logical. >> >> Since 'addr' may contain a physical, logical, or virtual address the >> easiest solution is to just change the type to 'phys_addr_t' which >> should always be greater than or equal to the sizeof(void *) such that >> it can properly hold any of the address types. >> >> For physical address we can support up to a 44-bit physical address on a >> typical 32-bit system as we utilize remap_pfn_range() for the mapping of >> the memory region and pfn's are represnted by shifting the address by >> the page size (typically 4k). >> >> Signed-off-by: Kai Jiang <Kai.Jiang@freescale.com> >> Signed-off-by: Minghuan Lian <Minghuan.Lian@freescale.com> >> Signed-off-by: Kumar Gala <galak@kernel.crashing.org> > > Signed-off-by: "Hans J. Koch" <hjk@hansjkoch.de> > > That looks good to me. There's an unnecessary cast (see below), but I fixed that > on the way. > > Greg, please pull this from branch uio-for-gregkh from > > git://hansjkoch.de/git/linux-hjk > > Thanks, > Hans
I think removing that cast is wrong:
drivers/uio/uio.c: In function 'uio_vma_fault': drivers/uio/uio.c:637:26: warning: cast to pointer from integer of different size
- k
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