From 402d326519c1a4859c527702383f4e60f606ef52 Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 12 Feb 2009 10:40:00 +0000 Subject: NOMMU: Present backing device capabilities for MTD chardevs Present backing device capabilities for MTD character device files to allow NOMMU mmap to do direct mapping where possible. Signed-off-by: David Howells Tested-by: Bernd Schmidt Signed-off-by: David Woodhouse --- drivers/mtd/mtdbdi.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 drivers/mtd/mtdbdi.c (limited to 'drivers/mtd/mtdbdi.c') diff --git a/drivers/mtd/mtdbdi.c b/drivers/mtd/mtdbdi.c new file mode 100644 index 00000000000..5ca5aed0b22 --- /dev/null +++ b/drivers/mtd/mtdbdi.c @@ -0,0 +1,43 @@ +/* MTD backing device capabilities + * + * Copyright © 2006 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include "internal.h" + +/* + * backing device capabilities for non-mappable devices (such as NAND flash) + * - permits private mappings, copies are taken of the data + */ +struct backing_dev_info mtd_bdi_unmappable = { + .capabilities = BDI_CAP_MAP_COPY, +}; + +/* + * backing device capabilities for R/O mappable devices (such as ROM) + * - permits private mappings, copies are taken of the data + * - permits non-writable shared mappings + */ +struct backing_dev_info mtd_bdi_ro_mappable = { + .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT | + BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP), +}; + +/* + * backing device capabilities for writable mappable devices (such as RAM) + * - permits private mappings, copies are taken of the data + * - permits non-writable shared mappings + */ +struct backing_dev_info mtd_bdi_rw_mappable = { + .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT | + BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP | + BDI_CAP_WRITE_MAP), +}; -- cgit v1.2.3-70-g09d2