docs: cma/debugfs.txt: convert docs to ReST and rename to *.rst

The debugfs interface for CMA should be there together with other
mm-related documents.

Convert this small file to ReST and move it to its rightful place.

The conversion is actually quite simple: just add a title for the
document. In order to make it to look better for the audience,
also mark the "echo" command as a literal block.

While this is not part of any book, mark it as :orphan:,
in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/Documentation/cma/debugfs.rst b/Documentation/cma/debugfs.rst
new file mode 100644 (file)
index 0000000..518fe40
--- /dev/null
+++ b/Documentation/cma/debugfs.rst
@@ -0,0 +1,27 @@
+:orphan:
+
+=====================
+CMA Debugfs Interface
+=====================
+
+The CMA debugfs interface is useful to retrieve basic information out of the
+different CMA areas and to test allocation/release in each of the areas.
+
+Each CMA zone represents a directory under <debugfs>/cma/, indexed by the
+kernel's CMA index. So the first CMA zone would be:
+
+       <debugfs>/cma/cma-0
+
+The structure of the files created under that directory is as follows:
+
+ - [RO] base_pfn: The base PFN (Page Frame Number) of the zone.
+ - [RO] count: Amount of memory in the CMA area.
+ - [RO] order_per_bit: Order of pages represented by one bit.
+ - [RO] bitmap: The bitmap of page states in the zone.
+ - [WO] alloc: Allocate N pages from that CMA area. For example::
+
+       echo 5 > <debugfs>/cma/cma-2/alloc
+
+would try to allocate 5 pages from the cma-2 area.
+
+ - [WO] free: Free N pages from that CMA area, similar to the above.

diff --git a/Documentation/cma/debugfs.txt b/Documentation/cma/debugfs.txt
deleted file mode 100644 (file)
index 6cef20a..0000000
--- a/Documentation/cma/debugfs.txt
+++ /dev/null
@@ -1,21 +0,0 @@
-The CMA debugfs interface is useful to retrieve basic information out of the
-different CMA areas and to test allocation/release in each of the areas.
-
-Each CMA zone represents a directory under <debugfs>/cma/, indexed by the
-kernel's CMA index. So the first CMA zone would be:
-
-       <debugfs>/cma/cma-0
-
-The structure of the files created under that directory is as follows:
-
- - [RO] base_pfn: The base PFN (Page Frame Number) of the zone.
- - [RO] count: Amount of memory in the CMA area.
- - [RO] order_per_bit: Order of pages represented by one bit.
- - [RO] bitmap: The bitmap of page states in the zone.
- - [WO] alloc: Allocate N pages from that CMA area. For example:
-
-       echo 5 > <debugfs>/cma/cma-2/alloc
-
-would try to allocate 5 pages from the cma-2 area.
-
- - [WO] free: Free N pages from that CMA area, similar to the above.