[PATCH] mm/gfp: Add kernel-doc for gfp_t

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

The generated html will link to the definition of the gfp_t automatically
once we define it.  Move the one-paragraph overview of GFP flags from the
documentation directory into gfp.h and pull gfp.h into the documentation.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 Documentation/core-api/mm-api.rst |  7 ++-----
 include/linux/gfp.h               | 11 +++++++++++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/Documentation/core-api/mm-api.rst b/Documentation/core-api/mm-api.rst
index 2adffb3f7914..201b5423303b 100644
--- a/Documentation/core-api/mm-api.rst
+++ b/Documentation/core-api/mm-api.rst
@@ -19,11 +19,8 @@ User Space Memory Access
 Memory Allocation Controls
 ==========================
 
-Functions which need to allocate memory often use GFP flags to express
-how that memory should be allocated. The GFP acronym stands for "get
-free pages", the underlying memory allocation function. Not every GFP
-flag is allowed to every function which may allocate memory. Most
-users will want to use a plain ``GFP_KERNEL``.
+.. kernel-doc:: include/linux/gfp.h
+   :internal:
 
 .. kernel-doc:: include/linux/gfp.h
    :doc: Page mobility and placement hints
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 52cd415b436c..ecd1b5d27936 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -8,6 +8,17 @@
 #include <linux/linkage.h>
 #include <linux/topology.h>
 
+/**
+ * typedef gfp_t - Memory allocation flags.
+ *
+ * GFP flags are commonly used throughout Linux to indicate how memory
+ * should be allocated.  The GFP acronym stands for "get free pages",
+ * the underlying memory allocation function.  Not every GFP flag is
+ * supported by every function which may allocate memory.  Most users
+ * will want to use a plain ``GFP_KERNEL``.
+ */
+typedef unsigned int __bitwise gfp_t;	// repeated here for kernel-doc
+
 struct vm_area_struct;
 
 /*
-- 
2.29.2