Op 22-01-13 17:47, Francesco Lavra schreef:
On 01/15/2013 01:34 PM, Maarten Lankhorst wrote:
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.
Signed-off-by: Maarten Lankhorst maarten.lankhorst@canonical.com
Documentation/DocBook/device-drivers.tmpl | 2 + drivers/base/Makefile | 2 +- drivers/base/reservation.c | 251 ++++++++++++++++++++++++++++++ include/linux/reservation.h | 182 ++++++++++++++++++++++ 4 files changed, 436 insertions(+), 1 deletion(-) create mode 100644 drivers/base/reservation.c create mode 100644 include/linux/reservation.h
[...]
diff --git a/include/linux/reservation.h b/include/linux/reservation.h new file mode 100644 index 0000000..fc2349d --- /dev/null +++ b/include/linux/reservation.h @@ -0,0 +1,182 @@ +/*
- Header file for reservations for dma-buf and ttm
- Copyright(C) 2011 Linaro Limited. All rights reserved.
- Copyright (C) 2012 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/spinlock.h> +#include <linux/mutex.h> +#include <linux/fence.h>
+#define BUF_MAX_SHARED_FENCE 8
+struct fence;
+extern atomic_long_t reservation_counter; +extern const char reservation_object_name[]; +extern struct lock_class_key reservation_object_class; +extern const char reservation_ticket_name[]; +extern struct lock_class_key reservation_ticket_class;
+struct reservation_object {
- struct ticket_mutex lock;
- u32 fence_shared_count;
- struct fence *fence_excl;
- struct fence *fence_shared[BUF_MAX_SHARED_FENCE];
+};
+struct reservation_ticket {
- unsigned long seqno;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
+#endif +};
+/**
- struct reservation_entry - reservation structure for a
- reservation_object
- @head: list entry
- @obj_shared: pointer to a reservation_object to reserve
- Bit 0 of obj_shared is set to bool shared, as such pointer has to be
- converted back, which can be done with reservation_entry_get.
- */
+struct reservation_entry {
- struct list_head head;
- unsigned long obj_shared;
+};
+static inline void +reservation_object_init(struct reservation_object *obj) +{
- obj->fence_shared_count = 0;
- obj->fence_excl = NULL;
- __ticket_mutex_init(&obj->lock, reservation_object_name,
&reservation_object_class);+}
+static inline void +reservation_object_fini(struct reservation_object *obj) +{
- int i;
- if (obj->fence_excl)
fence_put(obj->fence_excl);- for (i = 0; i < obj->fence_shared_count; ++i)
fence_put(obj->fence_shared[i]);- mutex_destroy(&obj->lock.base);
+}
+static inline void +reservation_ticket_init(struct reservation_ticket *t) +{ +#ifdef CONFIG_DEBUG_LOCK_ALLOC
- /*
* Make sure we are not reinitializing a held ticket:*/- debug_check_no_locks_freed((void *)t, sizeof(*t));
- lockdep_init_map(&t->dep_map, reservation_ticket_name,
&reservation_ticket_class, 0);+#endif
- mutex_acquire(&t->dep_map, 0, 0, _THIS_IP_);
If CONFIG_DEBUG_LOCK_ALLOC is not defined, t->dep_map is not there.
And mutex_acquire will not expand either, so it's harmless. :-)
- do {
t->seqno = atomic_long_inc_return(&reservation_counter);- } while (unlikely(!t->seqno));
+}
-- Francesco