diff options
Diffstat (limited to 'nx-X11/extras/drm/bsd-core/drm_lock.c')
| -rw-r--r-- | nx-X11/extras/drm/bsd-core/drm_lock.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/nx-X11/extras/drm/bsd-core/drm_lock.c b/nx-X11/extras/drm/bsd-core/drm_lock.c new file mode 100644 index 000000000..d0e61d3ab --- /dev/null +++ b/nx-X11/extras/drm/bsd-core/drm_lock.c @@ -0,0 +1,177 @@ +/* lock.c -- IOCTLs for locking -*- linux-c -*- + * 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. + * + * Authors: + * Rickard E. (Rik) Faith <faith@valinux.com> + * Gareth Hughes <gareth@valinux.com> + * + */ + +#include "drmP.h" + +int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context) +{ + unsigned int old, new; + + do { + old = *lock; + if (old & _DRM_LOCK_HELD) new = old | _DRM_LOCK_CONT; + else new = context | _DRM_LOCK_HELD; + } while (!atomic_cmpset_int(lock, old, new)); + + 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. */ +int drm_lock_transfer(drm_device_t *dev, + __volatile__ unsigned int *lock, unsigned int context) +{ + unsigned int old, new; + + dev->lock.filp = NULL; + do { + old = *lock; + new = context | _DRM_LOCK_HELD; + } while (!atomic_cmpset_int(lock, old, new)); + + return 1; +} + +int drm_lock_free(drm_device_t *dev, + __volatile__ unsigned int *lock, unsigned int context) +{ + unsigned int old, new; + + dev->lock.filp = NULL; + do { + old = *lock; + new = 0; + } while (!atomic_cmpset_int(lock, old, new)); + + 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; + } + DRM_WAKEUP_INT((void *)&dev->lock.lock_queue); + return 0; +} + +int drm_lock(DRM_IOCTL_ARGS) +{ + DRM_DEVICE; + drm_lock_t lock; + int ret = 0; + + DRM_COPY_FROM_USER_IOCTL(lock, (drm_lock_t *)data, sizeof(lock)); + + if (lock.context == DRM_KERNEL_CONTEXT) { + DRM_ERROR("Process %d using kernel context %d\n", + DRM_CURRENTPID, lock.context); + return EINVAL; + } + + DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n", + lock.context, DRM_CURRENTPID, dev->lock.hw_lock->lock, lock.flags); + + if (dev->driver.use_dma_queue && lock.context < 0) + return EINVAL; + + DRM_LOCK(); + for (;;) { + if (drm_lock_take(&dev->lock.hw_lock->lock, lock.context)) { + dev->lock.filp = (void *)(uintptr_t)DRM_CURRENTPID; + dev->lock.lock_time = jiffies; + atomic_inc(&dev->counts[_DRM_STAT_LOCKS]); + break; /* Got lock */ + } + + /* Contention */ +#if defined(__FreeBSD__) && __FreeBSD_version > 500000 + ret = msleep((void *)&dev->lock.lock_queue, &dev->dev_lock, + PZERO | PCATCH, "drmlk2", 0); +#else + ret = tsleep((void *)&dev->lock.lock_queue, PZERO | PCATCH, + "drmlk2", 0); +#endif + if (ret != 0) + break; + } + DRM_UNLOCK(); + DRM_DEBUG("%d %s\n", lock.context, ret ? "interrupted" : "has lock"); + + if (ret != 0) + return ret; + + /* XXX: Add signal blocking here */ + + if (dev->driver.dma_quiescent != NULL && + (lock.flags & _DRM_LOCK_QUIESCENT)) + dev->driver.dma_quiescent(dev); + + return 0; +} + +int drm_unlock(DRM_IOCTL_ARGS) +{ + DRM_DEVICE; + drm_lock_t lock; + + DRM_COPY_FROM_USER_IOCTL(lock, (drm_lock_t *)data, sizeof(lock)); + + if (lock.context == DRM_KERNEL_CONTEXT) { + DRM_ERROR("Process %d using kernel context %d\n", + DRM_CURRENTPID, lock.context); + return EINVAL; + } + + atomic_inc(&dev->counts[_DRM_STAT_UNLOCKS]); + + DRM_LOCK(); + drm_lock_transfer(dev, &dev->lock.hw_lock->lock, DRM_KERNEL_CONTEXT); + + if (drm_lock_free(dev, &dev->lock.hw_lock->lock, DRM_KERNEL_CONTEXT)) { + DRM_ERROR("\n"); + } + DRM_UNLOCK(); + + return 0; +} |