[PATCH] vm: introduce remap_pfn_range() to replace remap_page_range()

This patch introduces remap_pfn_range(), destined to replace
remap_page_range(), to which all callers of remap_page_range() are converted
in the sequel.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 9 insertions, 12 deletions

diff --git a/mm/memory.c b/mm/memory.c
index c43881bbd00d28..556ed18f7f2ea4 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -918,16 +918,14 @@ int zeromap_page_range(struct vm_area_struct *vma, unsigned long address, unsign
  * in null mappings (currently treated as "copy-on-access")
  */
 static inline void remap_pte_range(pte_t * pte, unsigned long address, unsigned long size,
-	unsigned long phys_addr, pgprot_t prot)
+	unsigned long pfn, pgprot_t prot)
 {
 	unsigned long end;
-	unsigned long pfn;
 
 	address &= ~PMD_MASK;
 	end = address + size;
 	if (end > PMD_SIZE)
 		end = PMD_SIZE;
-	pfn = phys_addr >> PAGE_SHIFT;
 	do {
 		BUG_ON(!pte_none(*pte));
 		if (!pfn_valid(pfn) || PageReserved(pfn_to_page(pfn)))
@@ -939,7 +937,7 @@ static inline void remap_pte_range(pte_t * pte, unsigned long address, unsigned
 }
 
 static inline int remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned long address, unsigned long size,
-	unsigned long phys_addr, pgprot_t prot)
+	unsigned long pfn, pgprot_t prot)
 {
 	unsigned long base, end;
 
@@ -948,12 +946,12 @@ static inline int remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned lo
 	end = address + size;
 	if (end > PGDIR_SIZE)
 		end = PGDIR_SIZE;
-	phys_addr -= address;
+	pfn -= address >> PAGE_SHIFT;
 	do {
 		pte_t * pte = pte_alloc_map(mm, pmd, base + address);
 		if (!pte)
 			return -ENOMEM;
-		remap_pte_range(pte, base + address, end - address, address + phys_addr, prot);
+		remap_pte_range(pte, base + address, end - address, pfn + (address >> PAGE_SHIFT), prot);
 		pte_unmap(pte);
 		address = (address + PMD_SIZE) & PMD_MASK;
 		pmd++;
@@ -962,7 +960,7 @@ static inline int remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned lo
 }
 
 /*  Note: this is only safe if the mm semaphore is held when called. */
-int remap_page_range(struct vm_area_struct *vma, unsigned long from, unsigned long phys_addr, unsigned long size, pgprot_t prot)
+int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot)
 {
 	int error = 0;
 	pgd_t * dir;
@@ -970,7 +968,7 @@ int remap_page_range(struct vm_area_struct *vma, unsigned long from, unsigned lo
 	unsigned long end = from + size;
 	struct mm_struct *mm = vma->vm_mm;
 
-	phys_addr -= from;
+	pfn -= from >> PAGE_SHIFT;
 	dir = pgd_offset(mm, from);
 	flush_cache_range(vma, beg, end);
 	if (from >= end)
@@ -982,7 +980,7 @@ int remap_page_range(struct vm_area_struct *vma, unsigned long from, unsigned lo
 		error = -ENOMEM;
 		if (!pmd)
 			break;
-		error = remap_pmd_range(mm, pmd, from, end - from, phys_addr + from, prot);
+		error = remap_pmd_range(mm, pmd, from, end - from, pfn + (from >> PAGE_SHIFT), prot);
 		if (error)
 			break;
 		from = (from + PGDIR_SIZE) & PGDIR_MASK;
@@ -995,8 +993,7 @@ int remap_page_range(struct vm_area_struct *vma, unsigned long from, unsigned lo
 	spin_unlock(&mm->page_table_lock);
 	return error;
 }
-
-EXPORT_SYMBOL(remap_page_range);
+EXPORT_SYMBOL(remap_pfn_range);
 
 /*
  * Do pte_mkwrite, but only if the vma says VM_WRITE.  We do this when
diff --git a/mm/nommu.c b/mm/nommu.c
index 68e6b32dea6a64..f749f023e565b6 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -560,7 +560,7 @@ struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr)
 	return NULL;
 }
 
-int remap_page_range(struct vm_area_struct *vma, unsigned long from,
+int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
 		unsigned long to, unsigned long size, pgprot_t prot)
 {
 	return -EPERM;