From f4092abdf94af6a99aff944d6264bc1284e8bdd4 Mon Sep 17 00:00:00 2001 From: Reinhard Tartler Date: Mon, 10 Oct 2011 17:43:39 +0200 Subject: Imported nx-X11-3.1.0-1.tar.gz Summary: Imported nx-X11-3.1.0-1.tar.gz Keywords: Imported nx-X11-3.1.0-1.tar.gz into Git repository --- nx-X11/extras/drm/linux/drm_lock.h | 168 +++++++++++++++++++++++++++++++++++++ 1 file changed, 168 insertions(+) create mode 100644 nx-X11/extras/drm/linux/drm_lock.h (limited to 'nx-X11/extras/drm/linux/drm_lock.h') diff --git a/nx-X11/extras/drm/linux/drm_lock.h b/nx-X11/extras/drm/linux/drm_lock.h new file mode 100644 index 000000000..55fb29f39 --- /dev/null +++ b/nx-X11/extras/drm/linux/drm_lock.h @@ -0,0 +1,168 @@ +/** + * \file drm_lock.h + * IOCTLs for locking + * + * \author Rickard E. (Rik) Faith + * \author Gareth Hughes + */ + +/* + * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com + * + * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. + * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. + * 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, sublicense, + * 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 NONINFRINGEMENT. IN NO EVENT SHALL + * VA LINUX SYSTEMS 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. + */ + +#include "drmP.h" + +/** No-op ioctl. */ +int DRM(noop)(struct inode *inode, struct file *filp, unsigned int cmd, + unsigned long arg) +{ + DRM_DEBUG("\n"); + return 0; +} + +/** + * Take the heavyweight lock. + * + * \param lock lock pointer. + * \param context locking context. + * \return one if the lock is held, or zero otherwise. + * + * Attempt to mark the lock as held by the given context, via the \p cmpxchg instruction. + */ +int DRM(lock_take)(__volatile__ unsigned int *lock, unsigned int context) +{ + unsigned int old, new, prev; + + do { + old = *lock; + if (old & _DRM_LOCK_HELD) new = old | _DRM_LOCK_CONT; + else new = context | _DRM_LOCK_HELD; + prev = cmpxchg(lock, old, new); + } while (prev != old); + if (_DRM_LOCKING_CONTEXT(old) == context) { + if (old & _DRM_LOCK_HELD) { + if (context != DRM_KERNEL_CONTEXT) { + DRM_ERROR("%d holds heavyweight lock\n", + context); + } + return 0; + } + } + if (new == (context | _DRM_LOCK_HELD)) { + /* Have lock */ + return 1; + } + return 0; +} + +/** + * This takes a lock forcibly and hands it to context. Should ONLY be used + * inside *_unlock to give lock to kernel before calling *_dma_schedule. + * + * \param dev DRM device. + * \param lock lock pointer. + * \param context locking context. + * \return always one. + * + * Resets the lock file pointer. + * Marks the lock as held by the given context, via the \p cmpxchg instruction. + */ +int DRM(lock_transfer)(drm_device_t *dev, + __volatile__ unsigned int *lock, unsigned int context) +{ + unsigned int old, new, prev; + + dev->lock.filp = NULL; + do { + old = *lock; + new = context | _DRM_LOCK_HELD; + prev = cmpxchg(lock, old, new); + } while (prev != old); + return 1; +} + +/** + * Free lock. + * + * \param dev DRM device. + * \param lock lock. + * \param context context. + * + * Resets the lock file pointer. + * Marks the lock as not held, via the \p cmpxchg instruction. Wakes any task + * waiting on the lock queue. + */ +int DRM(lock_free)(drm_device_t *dev, + __volatile__ unsigned int *lock, unsigned int context) +{ + unsigned int old, new, prev; + + dev->lock.filp = NULL; + do { + old = *lock; + new = 0; + prev = cmpxchg(lock, old, new); + } while (prev != old); + if (_DRM_LOCK_IS_HELD(old) && _DRM_LOCKING_CONTEXT(old) != context) { + DRM_ERROR("%d freed heavyweight lock held by %d\n", + context, + _DRM_LOCKING_CONTEXT(old)); + return 1; + } + wake_up_interruptible(&dev->lock.lock_queue); + return 0; +} + +/** + * If we get here, it means that the process has called DRM_IOCTL_LOCK + * without calling DRM_IOCTL_UNLOCK. + * + * If the lock is not held, then let the signal proceed as usual. If the lock + * is held, then set the contended flag and keep the signal blocked. + * + * \param priv pointer to a drm_sigdata structure. + * \return one if the signal should be delivered normally, or zero if the + * signal should be blocked. + */ +int DRM(notifier)(void *priv) +{ + drm_sigdata_t *s = (drm_sigdata_t *)priv; + unsigned int old, new, prev; + + + /* Allow signal delivery if lock isn't held */ + if (!s->lock || !_DRM_LOCK_IS_HELD(s->lock->lock) + || _DRM_LOCKING_CONTEXT(s->lock->lock) != s->context) return 1; + + /* Otherwise, set flag to force call to + drmUnlock */ + do { + old = s->lock->lock; + new = old | _DRM_LOCK_CONT; + prev = cmpxchg(&s->lock->lock, old, new); + } while (prev != old); + return 0; +} -- cgit v1.2.3