diff options
| author | Roland Dreier <rolandd@cisco.com> | 2005-10-29 02:46:18 +0200 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2005-10-29 06:25:49 +0200 |
| commit | 8b150478aeb1a8edb9015c2f7ac4da637ff65c45 (patch) | |
| tree | 621b038b9c041fe82b708c6c5cbee655be2a519a /arch/ppc | |
| parent | [PATCH] ppc32: update xmon help text (diff) | |
| download | linux-8b150478aeb1a8edb9015c2f7ac4da637ff65c45.tar.xz linux-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 'arch/ppc')
| -rw-r--r-- | arch/ppc/kernel/pci.c | 5 | ||||
| -rw-r--r-- | arch/ppc/mm/init.c | 10 |
2 files changed, 7 insertions, 8 deletions
diff --git a/arch/ppc/kernel/pci.c b/arch/ppc/kernel/pci.c index ad4ef2aaa6ab..e8f4e576750a 100644 --- a/arch/ppc/kernel/pci.c +++ b/arch/ppc/kernel/pci.c @@ -1594,16 +1594,17 @@ static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp, * above routine */ pgprot_t pci_phys_mem_access_prot(struct file *file, - unsigned long offset, + unsigned long pfn, unsigned long size, pgprot_t protection) { struct pci_dev *pdev = NULL; struct resource *found = NULL; unsigned long prot = pgprot_val(protection); + unsigned long offset = pfn << PAGE_SHIFT; int i; - if (page_is_ram(offset >> PAGE_SHIFT)) + if (page_is_ram(pfn)) return prot; prot |= _PAGE_NO_CACHE | _PAGE_GUARDED; diff --git a/arch/ppc/mm/init.c b/arch/ppc/mm/init.c index db94efd25369..99b48abd3296 100644 --- a/arch/ppc/mm/init.c +++ b/arch/ppc/mm/init.c @@ -637,18 +637,16 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, */ int page_is_ram(unsigned long pfn) { - unsigned long paddr = (pfn << PAGE_SHIFT); - - return paddr < __pa(high_memory); + return pfn < max_pfn; } -pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr, +pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot) { if (ppc_md.phys_mem_access_prot) - return ppc_md.phys_mem_access_prot(file, addr, size, vma_prot); + return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); - if (!page_is_ram(addr >> PAGE_SHIFT)) + if (!page_is_ram(pfn)) vma_prot = __pgprot(pgprot_val(vma_prot) | _PAGE_GUARDED | _PAGE_NO_CACHE); return vma_prot; |