diff options
| author |   Roland Dreier <rolandd@cisco.com> | 2005-10-28 17:46:18 -0700 |
|---|---|---|
| committer |   Paul Mackerras <paulus@samba.org> | 2005-10-29 14:25:49 +1000 |
| commit | 8b150478aeb1a8edb9015c2f7ac4da637ff65c45 (patch) | |
| tree | 621b038b9c041fe82b708c6c5cbee655be2a519a /drivers/char/mem.c | |
| parent | [PATCH] ppc32: update xmon help text (diff) | |
| download | linux-dev-8b150478aeb1a8edb9015c2f7ac4da637ff65c45.tar.xz linux-dev-8b150478aeb1a8edb9015c2f7ac4da637ff65c45.zip | |
[PATCH] ppc: make phys_mem_access_prot() work with pfns instead of addresses
Change the phys_mem_access_prot() function to take a pfn instead of an
address. This allows mmap64() to work on /dev/mem for addresses above 4G
on 32-bit architectures. We start with a pfn in mmap_mem(), so there's no
need to convert to an address; in fact, it's actively bad, since the
conversion can overflow when the address is above 4G.
Similarly fix the ppc32 page_is_ram() function to avoid a conversion to an
address by directly comparing to max_pfn. Working with max_pfn instead of
high_memory fixes page_is_ram() to give the right answer for highmem pages.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'drivers/char/mem.c')
| -rw-r--r-- | drivers/char/mem.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index f182752fe918..9df928d4f68d 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -231,9 +231,7 @@ static ssize_t write_mem(struct file * file, const char __user * buf, static int mmap_mem(struct file * file, struct vm_area_struct * vma) { #if defined(__HAVE_PHYS_MEM_ACCESS_PROT) - unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; - - vma->vm_page_prot = phys_mem_access_prot(file, offset, + vma->vm_page_prot = phys_mem_access_prot(file, vma->vm_pgoff, vma->vm_end - vma->vm_start, vma->vm_page_prot); #elif defined(pgprot_noncached) |