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-rw-r--r--Documentation/filesystems/iomap/design.rst9
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diff --git a/Documentation/filesystems/iomap/design.rst b/Documentation/filesystems/iomap/design.rst
index b0d0188a095e..e29651a42eec 100644
--- a/Documentation/filesystems/iomap/design.rst
+++ b/Documentation/filesystems/iomap/design.rst
@@ -246,6 +246,10 @@ The fields are as follows:
* **IOMAP_F_PRIVATE**: Starting with this value, the upper bits can
be set by the filesystem for its own purposes.
+ * **IOMAP_F_ANON_WRITE**: Indicates that (write) I/O does not have a target
+ block assigned to it yet and the file system will do that in the bio
+ submission handler, splitting the I/O as needed.
+
These flags can be set by iomap itself during file operations.
The filesystem should supply an ``->iomap_end`` function if it needs
to observe these flags:
@@ -352,6 +356,11 @@ operations:
``IOMAP_NOWAIT`` is often set on behalf of ``IOCB_NOWAIT`` or
``RWF_NOWAIT``.
+ * ``IOMAP_DONTCACHE`` is set when the caller wishes to perform a
+ buffered file I/O and would like the kernel to drop the pagecache
+ after the I/O completes, if it isn't already being used by another
+ thread.
+
If it is necessary to read existing file contents from a `different
<https://lore.kernel.org/all/20191008071527.29304-9-hch@lst.de/>`_
device or address range on a device, the filesystem should return that