Revert "[PATCH] x86: __pa and __pa_symbol address space separation"

This was broken.  It adds complexity, for no good reason.  Rather than
separate __pa() and __pa_symbol(), we should deprecate __pa_symbol(),
and preferably __pa() too - and just use "virt_to_phys()" instead, which
is more readable and has nicer semantics.

However, right now, just undo the separation, and make __pa_symbol() be
the exact same as __pa().  That fixes the bugs this patch introduced,
and we can do the fairly obvious cleanups later.

Do the new __phys_addr() function (which is now the actual workhorse for
the unified __pa()/__pa_symbol()) as a real external function, that way
all the potential issues with compile/link-time optimizations of
constant symbol addresses go away, and we can also, if we choose to, add
more sanity-checking of the argument.

Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c
index dbe16f6..1a7197e 100644
--- a/arch/i386/mm/init.c
+++ b/arch/i386/mm/init.c
@@ -843,11 +843,10 @@
 	unsigned long addr;
 
 	for (addr = begin; addr < end; addr += PAGE_SIZE) {
-		struct page *page = pfn_to_page(addr >> PAGE_SHIFT);
-		ClearPageReserved(page);
-		init_page_count(page);
-		memset(page_address(page), POISON_FREE_INITMEM, PAGE_SIZE);
-		__free_page(page);
+		ClearPageReserved(virt_to_page(addr));
+		init_page_count(virt_to_page(addr));
+		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
+		free_page(addr);
 		totalram_pages++;
 	}
 	printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
@@ -856,14 +855,14 @@
 void free_initmem(void)
 {
 	free_init_pages("unused kernel memory",
-			__pa_symbol(&__init_begin),
-			__pa_symbol(&__init_end));
+			(unsigned long)(&__init_begin),
+			(unsigned long)(&__init_end));
 }
 
 #ifdef CONFIG_BLK_DEV_INITRD
 void free_initrd_mem(unsigned long start, unsigned long end)
 {
-	free_init_pages("initrd memory", __pa(start), __pa(end));
+	free_init_pages("initrd memory", start, end);
 }
 #endif