This adds support for a generic reservations framework that can be hooked up to ttm and dma-buf and allows easy sharing of reservations across devices.
The idea is that a dma-buf and ttm object both will get a pointer to a struct reservation_object, which has to be reserved before anything is done with the contents of the dma-buf.
Changes since v1: - Fix locking issue in ticket_reserve, which could cause mutex_unlock to be called too many times. Changes since v2: - All fence related calls and members have been taken out for now, what's left is the bare minimum to be useful for ttm locking conversion. Changes since v3: - Removed helper functions too. The documentation has an example implementation for locking. With the move to ww_mutex there is no need to have much logic any more.
Signed-off-by: Maarten Lankhorst maarten.lankhorst@canonical.com --- Documentation/DocBook/device-drivers.tmpl | 2 + drivers/base/Makefile | 2 +- drivers/base/reservation.c | 39 +++++++++++++++++++ include/linux/reservation.h | 62 +++++++++++++++++++++++++++++++ 4 files changed, 104 insertions(+), 1 deletion(-) create mode 100644 drivers/base/reservation.c create mode 100644 include/linux/reservation.h
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl index c36892c..f0648a8 100644 --- a/Documentation/DocBook/device-drivers.tmpl +++ b/Documentation/DocBook/device-drivers.tmpl @@ -126,6 +126,8 @@ X!Edrivers/base/interface.c </sect1> <sect1><title>Device Drivers DMA Management</title> !Edrivers/base/dma-buf.c +!Edrivers/base/reservation.c +!Iinclude/linux/reservation.h !Edrivers/base/dma-coherent.c !Edrivers/base/dma-mapping.c </sect1> diff --git a/drivers/base/Makefile b/drivers/base/Makefile index 4e22ce3..48029aa 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -10,7 +10,7 @@ obj-$(CONFIG_CMA) += dma-contiguous.o obj-y += power/ obj-$(CONFIG_HAS_DMA) += dma-mapping.o obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o -obj-$(CONFIG_DMA_SHARED_BUFFER) += dma-buf.o +obj-$(CONFIG_DMA_SHARED_BUFFER) += dma-buf.o reservation.o obj-$(CONFIG_ISA) += isa.o obj-$(CONFIG_FW_LOADER) += firmware_class.o obj-$(CONFIG_NUMA) += node.o diff --git a/drivers/base/reservation.c b/drivers/base/reservation.c new file mode 100644 index 0000000..a73fbf3 --- /dev/null +++ b/drivers/base/reservation.c @@ -0,0 +1,39 @@ +/* + * Copyright (C) 2012-2013 Canonical Ltd + * + * Based on bo.c which bears the following copyright notice, + * but is dual licensed: + * + * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + * + **************************************************************************/ +/* + * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> + */ + +#include <linux/reservation.h> +#include <linux/export.h> + +DEFINE_WW_CLASS(reservation_ww_class); +EXPORT_SYMBOL(reservation_ww_class); diff --git a/include/linux/reservation.h b/include/linux/reservation.h new file mode 100644 index 0000000..e9ee806 --- /dev/null +++ b/include/linux/reservation.h @@ -0,0 +1,62 @@ +/* + * Header file for reservations for dma-buf and ttm + * + * Copyright(C) 2011 Linaro Limited. All rights reserved. + * Copyright (C) 2012-2013 Canonical Ltd + * Copyright (C) 2012 Texas Instruments + * + * Authors: + * Rob Clark rob.clark@linaro.org + * Maarten Lankhorst maarten.lankhorst@canonical.com + * Thomas Hellstrom <thellstrom-at-vmware-dot-com> + * + * Based on bo.c which bears the following copyright notice, + * but is dual licensed: + * + * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +#ifndef _LINUX_RESERVATION_H +#define _LINUX_RESERVATION_H + +#include <linux/mutex.h> + +extern struct ww_class reservation_ww_class; + +struct reservation_object { + struct ww_mutex lock; +}; + +static inline void +reservation_object_init(struct reservation_object *obj) +{ + ww_mutex_init(&obj->lock, &reservation_ww_class); +} + +static inline void +reservation_object_fini(struct reservation_object *obj) +{ + ww_mutex_destroy(&obj->lock); +} + +#endif /* _LINUX_RESERVATION_H */