[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>

6 files changed, 6 insertions, 6 deletions

diff --git a/include/asm-powerpc/machdep.h b/include/asm-powerpc/machdep.h
index 706508b1b04..451b345cfc7 100644
--- a/include/asm-powerpc/machdep.h
+++ b/include/asm-powerpc/machdep.h
@@ -144,7 +144,7 @@ struct machdep_calls {
 	
 	/* Get access protection for /dev/mem */
 	pgprot_t	(*phys_mem_access_prot)(struct file *file,
-						unsigned long offset,
+						unsigned long pfn,
 						unsigned long size,
 						pgprot_t vma_prot);
 
diff --git a/include/asm-ppc/machdep.h b/include/asm-ppc/machdep.h
index 6c6d23abbe9..f01255bd1dc 100644
--- a/include/asm-ppc/machdep.h
+++ b/include/asm-ppc/machdep.h
@@ -98,7 +98,7 @@ struct machdep_calls {
 
 	/* Get access protection for /dev/mem */
 	pgprot_t	(*phys_mem_access_prot)(struct file *file,
-						unsigned long offset,
+						unsigned long pfn,
 						unsigned long size,
 						pgprot_t vma_prot);
 
diff --git a/include/asm-ppc/pci.h b/include/asm-ppc/pci.h
index 643740dd727..61434edbad7 100644
--- a/include/asm-ppc/pci.h
+++ b/include/asm-ppc/pci.h
@@ -126,7 +126,7 @@ extern void pcibios_add_platform_entries(struct pci_dev *dev);
 
 struct file;
 extern pgprot_t	pci_phys_mem_access_prot(struct file *file,
-					 unsigned long offset,
+					 unsigned long pfn,
 					 unsigned long size,
 					 pgprot_t prot);
 
diff --git a/include/asm-ppc/pgtable.h b/include/asm-ppc/pgtable.h
index eee601bb9ad..b28a713ba86 100644
--- a/include/asm-ppc/pgtable.h
+++ b/include/asm-ppc/pgtable.h
@@ -705,7 +705,7 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty)
 #define pgprot_noncached(prot)	(__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED))
 
 struct file;
-extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr,
+extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 				     unsigned long size, pgprot_t vma_prot);
 #define __HAVE_PHYS_MEM_ACCESS_PROT
 
diff --git a/include/asm-ppc64/pci.h b/include/asm-ppc64/pci.h
index a88bbfc2696..342e2d75555 100644
--- a/include/asm-ppc64/pci.h
+++ b/include/asm-ppc64/pci.h
@@ -168,7 +168,7 @@ extern void pcibios_add_platform_entries(struct pci_dev *dev);
 
 struct file;
 extern pgprot_t	pci_phys_mem_access_prot(struct file *file,
-					 unsigned long offset,
+					 unsigned long pfn,
 					 unsigned long size,
 					 pgprot_t prot);
 
diff --git a/include/asm-ppc64/pgtable.h b/include/asm-ppc64/pgtable.h
index c83679c9d2b..8cf5991540e 100644
--- a/include/asm-ppc64/pgtable.h
+++ b/include/asm-ppc64/pgtable.h
@@ -471,7 +471,7 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty)
 #define pgprot_noncached(prot)	(__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED))
 
 struct file;
-extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr,
+extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 				     unsigned long size, pgprot_t vma_prot);
 #define __HAVE_PHYS_MEM_ACCESS_PROT