[PATCH] mm: clarify a confusing comment for vm_iomap_memory

[Wang Wenhu]

The param "start" actually referes to the physical memory start,
which is to be mapped into virtual area vma. And it is the field
vma->vm_start which stands for the start of the area.

Most of the time, we do not read through whole implementation
of a function but only the definition and essential comments.
Accurate comments are definitely the base stone.

Signed-off-by: Wang Wenhu <wenhu.wang@xxxxxxxx>
---
 mm/memory.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/memory.c b/mm/memory.c
index 583f84519870..5c356a57b892 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2009,7 +2009,7 @@ EXPORT_SYMBOL(remap_pfn_range);
 /**
  * vm_iomap_memory - remap memory to userspace
  * @vma: user vma to map to
- * @start: start of area
+ * @start: start of the physical memory to be mapped
  * @len: size of area
  *
  * This is a simplified io_remap_pfn_range() for common driver use. The
-- 
2.17.1