x86: unify free_init_pages() and free_initmem()
Impact: unification
This patch introduces a common arch/x86/mm/init.c and moves the identical
free_init_pages() and free_initmem() functions to the file.
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <1236078906.2675.18.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
new file mode 100644
index 0000000..ce6a722
--- /dev/null
+++ b/arch/x86/mm/init.c
@@ -0,0 +1,49 @@
+#include <linux/swap.h>
+#include <asm/cacheflush.h>
+#include <asm/page.h>
+#include <asm/sections.h>
+#include <asm/system.h>
+
+void free_init_pages(char *what, unsigned long begin, unsigned long end)
+{
+ unsigned long addr = begin;
+
+ if (addr >= end)
+ return;
+
+ /*
+ * If debugging page accesses then do not free this memory but
+ * mark them not present - any buggy init-section access will
+ * create a kernel page fault:
+ */
+#ifdef CONFIG_DEBUG_PAGEALLOC
+ printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
+ begin, PAGE_ALIGN(end));
+ set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
+#else
+ /*
+ * We just marked the kernel text read only above, now that
+ * we are going to free part of that, we need to make that
+ * writeable first.
+ */
+ set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
+
+ printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
+
+ for (; addr < end; addr += PAGE_SIZE) {
+ ClearPageReserved(virt_to_page(addr));
+ init_page_count(virt_to_page(addr));
+ memset((void *)(addr & ~(PAGE_SIZE-1)),
+ POISON_FREE_INITMEM, PAGE_SIZE);
+ free_page(addr);
+ totalram_pages++;
+ }
+#endif
+}
+
+void free_initmem(void)
+{
+ free_init_pages("unused kernel memory",
+ (unsigned long)(&__init_begin),
+ (unsigned long)(&__init_end));
+}