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Diffstat (limited to 'Documentation/filesystems/iomap/design.rst')
-rw-r--r-- | Documentation/filesystems/iomap/design.rst | 9 |
1 files changed, 9 insertions, 0 deletions
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 |