vGEM buffers are useful for passing data between software clients and hardware renders. By allowing the user to create and attach fences to the exported vGEM buffers (on the dma-buf), the user can implement a deferred renderer and queue hardware operations like flipping and then signal the buffer readiness (i.e. this allows the user to schedule operations out-of-order, but have them complete in-order).
This also makes it much easier to write tightly controlled testcases for dma-buf fencing and signaling between hardware drivers. v2: Don't pretend the fences exist in an ordered timeline, but allocate a separate fence-context for each fence so that the fences are unordered. Testcase: igt/vgem_basic/dmabuf-fence Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk> Cc: Sean Paul <seanpaul at chromium.org> Cc: Zach Reizner <zachr at google.com> Cc: Gustavo Padovan <gustavo.padovan at collabora.co.uk> Cc: Daniel Vetter <daniel.vetter at ffwll.ch> Acked-by: Zach Reizner <zachr at google.com> --- drivers/gpu/drm/vgem/Makefile | 2 +- drivers/gpu/drm/vgem/vgem_drv.c | 34 +++++++ drivers/gpu/drm/vgem/vgem_drv.h | 16 +++ drivers/gpu/drm/vgem/vgem_fence.c | 207 ++++++++++++++++++++++++++++++++++++++ include/uapi/drm/vgem_drm.h | 62 ++++++++++++ 5 files changed, 320 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/vgem/vgem_fence.c create mode 100644 include/uapi/drm/vgem_drm.h diff --git a/drivers/gpu/drm/vgem/Makefile b/drivers/gpu/drm/vgem/Makefile index 3f4c7b842028..bfcdea1330e6 100644 --- a/drivers/gpu/drm/vgem/Makefile +++ b/drivers/gpu/drm/vgem/Makefile @@ -1,4 +1,4 @@ ccflags-y := -Iinclude/drm -vgem-y := vgem_drv.o +vgem-y := vgem_drv.o vgem_fence.o obj-$(CONFIG_DRM_VGEM) += vgem.o diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index 29c2aab3c1a7..c15bafb06665 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -83,6 +83,34 @@ static const struct vm_operations_struct vgem_gem_vm_ops = { .close = drm_gem_vm_close, }; +static int vgem_open(struct drm_device *dev, struct drm_file *file) +{ + struct vgem_file *vfile; + int ret; + + vfile = kzalloc(sizeof(*vfile), GFP_KERNEL); + if (!vfile) + return -ENOMEM; + + file->driver_priv = vfile; + + ret = vgem_fence_open(vfile); + if (ret) { + kfree(vfile); + return ret; + } + + return 0; +} + +static void vgem_preclose(struct drm_device *dev, struct drm_file *file) +{ + struct vgem_file *vfile = file->driver_priv; + + vgem_fence_close(vfile); + kfree(vfile); +} + /* ioctls */ static struct drm_gem_object *vgem_gem_create(struct drm_device *dev, @@ -164,6 +192,8 @@ unref: } static struct drm_ioctl_desc vgem_ioctls[] = { + DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_AUTH|DRM_RENDER_ALLOW), + DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_AUTH|DRM_RENDER_ALLOW), }; static int vgem_mmap(struct file *filp, struct vm_area_struct *vma) @@ -271,9 +301,12 @@ static int vgem_prime_mmap(struct drm_gem_object *obj, static struct drm_driver vgem_driver = { .driver_features = DRIVER_GEM | DRIVER_PRIME, + .open = vgem_open, + .preclose = vgem_preclose, .gem_free_object_unlocked = vgem_gem_free_object, .gem_vm_ops = &vgem_gem_vm_ops, .ioctls = vgem_ioctls, + .num_ioctls = ARRAY_SIZE(vgem_ioctls), .fops = &vgem_driver_fops, .dumb_create = vgem_gem_dumb_create, @@ -328,5 +361,6 @@ module_init(vgem_init); module_exit(vgem_exit); MODULE_AUTHOR("Red Hat, Inc."); +MODULE_AUTHOR("Intel Corporation"); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL and additional rights"); diff --git a/drivers/gpu/drm/vgem/vgem_drv.h b/drivers/gpu/drm/vgem/vgem_drv.h index 988cbaae7588..1f8798ad329c 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.h +++ b/drivers/gpu/drm/vgem/vgem_drv.h @@ -32,9 +32,25 @@ #include <drm/drmP.h> #include <drm/drm_gem.h> +#include <uapi/drm/vgem_drm.h> + +struct vgem_file { + struct idr fence_idr; + struct mutex fence_mutex; +}; + #define to_vgem_bo(x) container_of(x, struct drm_vgem_gem_object, base) struct drm_vgem_gem_object { struct drm_gem_object base; }; +int vgem_fence_open(struct vgem_file *file); +int vgem_fence_attach_ioctl(struct drm_device *dev, + void *data, + struct drm_file *file); +int vgem_fence_signal_ioctl(struct drm_device *dev, + void *data, + struct drm_file *file); +void vgem_fence_close(struct vgem_file *file); + #endif diff --git a/drivers/gpu/drm/vgem/vgem_fence.c b/drivers/gpu/drm/vgem/vgem_fence.c new file mode 100644 index 000000000000..63095331c446 --- /dev/null +++ b/drivers/gpu/drm/vgem/vgem_fence.c @@ -0,0 +1,207 @@ +/* + * Copyright 2016 Intel Corporation + * + * 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 + * on the rights to use, copy, modify, merge, publish, distribute, sub + * license, and/or sell copies of the Software, and to permit persons to whom + * them 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 MERCHANTIBILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS 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 <linux/dma-buf.h> +#include <linux/reservation.h> + +#include "vgem_drv.h" + +struct vgem_fence { + struct fence base; + struct spinlock lock; +}; + +static const char *vgem_fence_get_driver_name(struct fence *fence) +{ + return "vgem"; +} + +static const char *vgem_fence_get_timeline_name(struct fence *fence) +{ + return "unbound"; +} + +static bool vgem_fence_signaled(struct fence *fence) +{ + return false; +} + +static bool vgem_fence_enable_signaling(struct fence *fence) +{ + return true; +} + +static void vgem_fence_value_str(struct fence *fence, char *str, int size) +{ + snprintf(str, size, "%u", 0); +} + +static void vgem_fence_timeline_value_str(struct fence *fence, char *str, + int size) +{ + snprintf(str, size, "%u", 0); +} + +const struct fence_ops vgem_fence_ops = { + .get_driver_name = vgem_fence_get_driver_name, + .get_timeline_name = vgem_fence_get_timeline_name, + .enable_signaling = vgem_fence_enable_signaling, + .signaled = vgem_fence_signaled, + .wait = fence_default_wait, + .fence_value_str = vgem_fence_value_str, + .timeline_value_str = vgem_fence_timeline_value_str, +}; + +static struct fence *vgem_fence_create(struct vgem_file *vfile) +{ + struct vgem_fence *fence; + + fence = kzalloc(sizeof(*fence), GFP_KERNEL); + if (!fence) + return NULL; + + spin_lock_init(&fence->lock); + fence_init(&fence->base, &vgem_fence_ops, &fence->lock, + fence_context_alloc(1), 0); + + return &fence->base; +} + +static int attach_dmabuf(struct drm_device *dev, + struct drm_gem_object *obj) +{ + struct dma_buf *dmabuf; + + if (obj->dma_buf) + return 0; + + dmabuf = dev->driver->gem_prime_export(dev, obj, 0); + if (IS_ERR(dmabuf)) + return PTR_ERR(dmabuf); + + obj->dma_buf = dmabuf; + drm_gem_object_reference(obj); + return 0; +} + +int vgem_fence_attach_ioctl(struct drm_device *dev, + void *data, + struct drm_file *file) +{ + struct drm_vgem_fence_attach *arg = data; + struct vgem_file *vfile = file->driver_priv; + struct reservation_object *resv; + struct drm_gem_object *obj; + struct fence *fence; + int ret; + + if (arg->flags & ~VGEM_FENCE_WRITE) + return -EINVAL; + + if (arg->pad) + return -EINVAL; + + obj = drm_gem_object_lookup(file, arg->handle); + if (!obj) + return -ENOENT; + + ret = attach_dmabuf(dev, obj); + if (ret) + goto out; + + fence = vgem_fence_create(vfile); + if (!fence) { + ret = -ENOMEM; + goto out; + } + + ret = 0; + resv = obj->dma_buf->resv; + mutex_lock(&resv->lock.base); + if (arg->flags & VGEM_FENCE_WRITE) + reservation_object_add_excl_fence(resv, fence); + else if ((ret = reservation_object_reserve_shared(resv)) == 0) + reservation_object_add_shared_fence(resv, fence); + mutex_unlock(&resv->lock.base); + + if (ret == 0) { + mutex_lock(&vfile->fence_mutex); + ret = idr_alloc(&vfile->fence_idr, fence, 1, 0, GFP_KERNEL); + mutex_unlock(&vfile->fence_mutex); + if (ret > 0) { + arg->out_fence = ret; + ret = 0; + } + } + if (ret) { + fence_signal(fence); + fence_put(fence); + } +out: + drm_gem_object_unreference_unlocked(obj); + return ret; +} + +int vgem_fence_signal_ioctl(struct drm_device *dev, + void *data, + struct drm_file *file) +{ + struct vgem_file *vfile = file->driver_priv; + struct drm_vgem_fence_signal *arg = data; + struct fence *fence; + + if (arg->flags) + return -EINVAL; + + mutex_lock(&vfile->fence_mutex); + fence = idr_replace(&vfile->fence_idr, NULL, arg->fence); + mutex_unlock(&vfile->fence_mutex); + if (!fence) + return -ENOENT; + if (IS_ERR(fence)) + return PTR_ERR(fence); + + fence_signal(fence); + fence_put(fence); + return 0; +} + +int vgem_fence_open(struct vgem_file *vfile) +{ + mutex_init(&vfile->fence_mutex); + idr_init(&vfile->fence_idr); + + return 0; +} + +static int __vgem_fence_idr_fini(int id, void *p, void *data) +{ + fence_signal(p); + fence_put(p); + return 0; +} + +void vgem_fence_close(struct vgem_file *vfile) +{ + idr_for_each(&vfile->fence_idr, __vgem_fence_idr_fini, vfile); + idr_destroy(&vfile->fence_idr); +} diff --git a/include/uapi/drm/vgem_drm.h b/include/uapi/drm/vgem_drm.h new file mode 100644 index 000000000000..352d2fae8de9 --- /dev/null +++ b/include/uapi/drm/vgem_drm.h @@ -0,0 +1,62 @@ +/* + * Copyright 2016 Intel Corporation + * 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 TUNGSTEN GRAPHICS 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 _UAPI_VGEM_DRM_H_ +#define _UAPI_VGEM_DRM_H_ + +#include "drm.h" + +#if defined(__cplusplus) +extern "C" { +#endif + +/* Please note that modifications to all structs defined here are + * subject to backwards-compatibility constraints. + */ +#define DRM_VGEM_FENCE_ATTACH 0x1 +#define DRM_VGEM_FENCE_SIGNAL 0x2 + +#define DRM_IOCTL_VGEM_FENCE_ATTACH DRM_IOWR( DRM_COMMAND_BASE + DRM_VGEM_FENCE_ATTACH, struct drm_vgem_fence_attach) +#define DRM_IOCTL_VGEM_FENCE_SIGNAL DRM_IOW( DRM_COMMAND_BASE + DRM_VGEM_FENCE_SIGNAL, struct drm_vgem_fence_signal) + +struct drm_vgem_fence_attach { + __u32 handle; + __u32 flags; +#define VGEM_FENCE_WRITE 0x1 + __u32 out_fence; + __u32 pad; +}; + +struct drm_vgem_fence_signal { + __u32 fence; + __u32 flags; +}; + +#if defined(__cplusplus) +} +#endif + +#endif /* _UAPI_VGEM_DRM_H_ */ -- 2.8.1