1 files changed, 44 insertions, 17 deletions

diff --git a/mm/util.c b/mm/util.c
index 8c7265afa29f..eaf63fc2c92f 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -5,6 +5,8 @@
 #include <linux/err.h>
 #include <linux/sched.h>
 #include <linux/security.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
 #include <asm/uaccess.h>
 
 #include "internal.h"
@@ -105,6 +107,25 @@ void *memdup_user(const void __user *src, size_t len)
 }
 EXPORT_SYMBOL(memdup_user);
 
+static __always_inline void *__do_krealloc(const void *p, size_t new_size,
+					   gfp_t flags)
+{
+	void *ret;
+	size_t ks = 0;
+
+	if (p)
+		ks = ksize(p);
+
+	if (ks >= new_size)
+		return (void *)p;
+
+	ret = kmalloc_track_caller(new_size, flags);
+	if (ret && p)
+		memcpy(ret, p, ks);
+
+	return ret;
+}
+
 /**
  * __krealloc - like krealloc() but don't free @p.
  * @p: object to reallocate memory for.
@@ -117,23 +138,11 @@ EXPORT_SYMBOL(memdup_user);
  */
 void *__krealloc(const void *p, size_t new_size, gfp_t flags)
 {
-	void *ret;
-	size_t ks = 0;
-
 	if (unlikely(!new_size))
 		return ZERO_SIZE_PTR;
 
-	if (p)
-		ks = ksize(p);
+	return __do_krealloc(p, new_size, flags);
 
-	if (ks >= new_size)
-		return (void *)p;
-
-	ret = kmalloc_track_caller(new_size, flags);
-	if (ret && p)
-		memcpy(ret, p, ks);
-
-	return ret;
 }
 EXPORT_SYMBOL(__krealloc);
 
@@ -145,7 +154,7 @@ EXPORT_SYMBOL(__krealloc);
  *
  * The contents of the object pointed to are preserved up to the
  * lesser of the new and old sizes.  If @p is %NULL, krealloc()
- * behaves exactly like kmalloc().  If @size is 0 and @p is not a
+ * behaves exactly like kmalloc().  If @new_size is 0 and @p is not a
  * %NULL pointer, the object pointed to is freed.
  */
 void *krealloc(const void *p, size_t new_size, gfp_t flags)
@@ -157,7 +166,7 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags)
 		return ZERO_SIZE_PTR;
 	}
 
-	ret = __krealloc(p, new_size, flags);
+	ret = __do_krealloc(p, new_size, flags);
 	if (ret && p != ret)
 		kfree(p);
 
@@ -286,7 +295,6 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
 {
 	mm->mmap_base = TASK_UNMAPPED_BASE;
 	mm->get_unmapped_area = arch_get_unmapped_area;
-	mm->unmap_area = arch_unmap_area;
 }
 #endif
 
@@ -348,12 +356,16 @@ unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
 {
 	unsigned long ret;
 	struct mm_struct *mm = current->mm;
+	unsigned long populate;
 
 	ret = security_mmap_file(file, prot, flag);
 	if (!ret) {
 		down_write(&mm->mmap_sem);
-		ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff);
+		ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff,
+				    &populate);
 		up_write(&mm->mmap_sem);
+		if (populate)
+			mm_populate(ret, populate);
 	}
 	return ret;
 }
@@ -371,6 +383,21 @@ unsigned long vm_mmap(struct file *file, unsigned long addr,
 }
 EXPORT_SYMBOL(vm_mmap);
 
+struct address_space *page_mapping(struct page *page)
+{
+	struct address_space *mapping = page->mapping;
+
+	VM_BUG_ON(PageSlab(page));
+	if (unlikely(PageSwapCache(page))) {
+		swp_entry_t entry;
+
+		entry.val = page_private(page);
+		mapping = swap_address_space(entry);
+	} else if ((unsigned long)mapping & PAGE_MAPPING_ANON)
+		mapping = NULL;
+	return mapping;
+}
+
 /* Tracepoints definitions. */
 EXPORT_TRACEPOINT_SYMBOL(kmalloc);
 EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);