@@ -60,24 +60,24 @@ do_xip_mapping_read(struct address_space
 
 	BUG_ON(!mapping->a_ops->get_xip_page);
 
-	index = *ppos >> PAGE_CACHE_SHIFT;
-	offset = *ppos & ~PAGE_CACHE_MASK;
+	index = page_cache_index(mapping, *ppos);
+	offset = page_cache_offset(mapping, *ppos);
 
 	isize = i_size_read(inode);
 	if (!isize)
 		goto out;
 
-	end_index = (isize - 1) >> PAGE_CACHE_SHIFT;
+	end_index = page_cache_index(mapping, isize - 1);
 	for (;;) {
 		struct page *page;
 		unsigned long nr, ret;
 
 		/* nr is the maximum number of bytes to copy from this page */
-		nr = PAGE_CACHE_SIZE;
+		nr = page_cache_size(mapping);
 		if (index >= end_index) {
 			if (index > end_index)
 				goto out;
-			nr = ((isize - 1) & ~PAGE_CACHE_MASK) + 1;
+			nr = page_cache_next(mapping, size - 1) + 1;
 			if (nr <= offset) {
 				goto out;
 			}

@@ -116,8 +116,8 @@ do_xip_mapping_read(struct address_space
 		 */
 		ret = actor(desc, page, offset, nr);
 		offset += ret;
-		index += offset >> PAGE_CACHE_SHIFT;
-		offset &= ~PAGE_CACHE_MASK;
+		index += page_cache_index(mapping, offset);
+		offset = page_cache_offset(mapping, offset);
 
 		if (ret == nr && desc->count)
 			continue;

@@ -130,7 +130,7 @@ no_xip_page:
 	}
 
 out:
-	*ppos = ((loff_t) index << PAGE_CACHE_SHIFT) + offset;
+	*ppos = page_cache_pos(mapping, index, offset);
 	if (filp)
 		file_accessed(filp);
 }

@@ -219,7 +219,7 @@ static int xip_file_fault(struct vm_area
 
 	/* XXX: are VM_FAULT_ codes OK? */
 
-	size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+	size = page_cache_next(mapping, i_size_read(inode));
 	if (vmf->pgoff >= size)
 		return VM_FAULT_SIGBUS;
 

@@ -289,9 +289,9 @@ __xip_file_write(struct file *filp, cons
 		size_t copied;
 		char *kaddr;
 
-		offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
-		index = pos >> PAGE_CACHE_SHIFT;
-		bytes = PAGE_CACHE_SIZE - offset;
+		offset = page_cache_offset(mapping, pos); /* Within page */
+		index = page_cache_index(mapping, pos);
+		bytes = page_cache_size(mapping) - offset;
 		if (bytes > count)
 			bytes = count;
 

@@ -402,8 +402,8 @@ EXPORT_SYMBOL_GPL(xip_file_write);
 int
 xip_truncate_page(struct address_space *mapping, loff_t from)
 {
-	pgoff_t index = from >> PAGE_CACHE_SHIFT;
-	unsigned offset = from & (PAGE_CACHE_SIZE-1);
+	pgoff_t index = page_cache_index(mapping, from);
+	unsigned offset = page_cache_offset(mapping, from);
 	unsigned blocksize;
 	unsigned length;
 	struct page *page;