diff options
| author | Bob Liu <lliubbo@gmail.com> | 2011-07-08 15:39:46 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-08-03 12:42:23 -0700 |
| commit | f8936c0405f71df612e6e4cb19dbed35caa79680 (patch) | |
| tree | 77474d653e9e2e6330080be1a9b419a96d28d3b8 | |
| parent | 0cd2efd36623c7888a9ae10a7e834cc20f6b300a (diff) | |
mm/nommu.c: fix remap_pfn_range()
commit 8f3b1327aa454bc8283e96bca7669c3c88b83f79 upstream.
remap_pfn_range() means map physical address pfn<<PAGE_SHIFT to user addr.
For nommu arch it's implemented by vma->vm_start = pfn << PAGE_SHIFT which
is wrong acroding the original meaning of this function. And some driver
developer using remap_pfn_range() with correct parameter will get
unexpected result because vm_start is changed. It should be implementd
like addr = pfn << PAGE_SHIFT but which is meanless on nommu arch, this
patch just make it simply return.
Parameter name and setting of vma->vm_flags also be fixed.
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | mm/nommu.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/mm/nommu.c b/mm/nommu.c index c4c542c736a..0376a4c3387 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1819,10 +1819,13 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address, return NULL; } -int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, - unsigned long to, unsigned long size, pgprot_t prot) +int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn, unsigned long size, pgprot_t prot) { - vma->vm_start = vma->vm_pgoff << PAGE_SHIFT; + if (addr != (pfn << PAGE_SHIFT)) + return -EINVAL; + + vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP; return 0; } EXPORT_SYMBOL(remap_pfn_range); |