Many users of drm_gem_object embed a struct reservation_object into
their subclassed struct, so let's add one to struct drm_gem_object.
This will allow removing the reservation object from the subclasses
and removing the ->gem_prime_res_obj callback.
With the addition, add a drm_gem_reservation_object_wait() helper
function for drivers to use in wait ioctls.
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: Maxime Ripard <maxime.ripard@xxxxxxxxxxx>
Cc: Sean Paul <sean@xxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
---
v2:
- Fix missing kerneldoc
- Reword todo with what is left todo.
- Fix timeout error handling (added to drm_gem_reservation_object_wait)
Documentation/gpu/todo.rst | 8 +++----
drivers/gpu/drm/drm_gem.c | 43 +++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/drm_prime.c | 1 +
include/drm/drm_gem.h | 21 ++++++++++++++++++
4 files changed, 69 insertions(+), 4 deletions(-)
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst
index 14191b64446d..c9ed55605641 100644
--- a/Documentation/gpu/todo.rst
+++ b/Documentation/gpu/todo.rst
@@ -209,12 +209,12 @@ Would be great to refactor this all into a set of small common helpers.
Contact: Daniel Vetter
-Put a reservation_object into drm_gem_object
+Remove the ->gem_prime_res_obj callback
--------------------------------------------
-This would remove the need for the ->gem_prime_res_obj callback. It would also
-allow us to implement generic helpers for waiting for a bo, allowing for quite a
-bit of refactoring in the various wait ioctl implementations.
+The ->gem_prime_res_obj callback can be removed from drivers by using the
+reservation_object in the drm_gem_object. It may also be possible to use the
+generic drm_gem_reservation_object_wait helper for waiting for a bo.
Contact: Daniel Vetter
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 8b55ece97967..b09acbc5a655 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -170,6 +170,10 @@ void drm_gem_private_object_init(struct drm_device *dev,
kref_init(&obj->refcount);
obj->handle_count = 0;
obj->size = size;
+ reservation_object_init(&obj->_resv);
+ if (!obj->resv)
+ obj->resv = &obj->_resv;
+
drm_vma_node_reset(&obj->vma_node);
}
EXPORT_SYMBOL(drm_gem_private_object_init);
@@ -657,6 +661,44 @@ drm_gem_object_lookup(struct drm_file *filp, u32 handle)
}
EXPORT_SYMBOL(drm_gem_object_lookup);
+/**
+ * drm_gem_reservation_object_wait - Wait on GEM object's reservation's objects
+ * shared and/or exclusive fences.
+ * @filep: DRM file private date
+ * @handle: userspace handle
+ * @wait_all: if true, wait on all fences, else wait on just exclusive fence
+ * @timeout: timeout value in jiffies or zero to return immediately
+ *
+ * Returns:
+ *
+ * Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or
+ * greater than 0 on success.
+ */
+long drm_gem_reservation_object_wait(struct drm_file *filep, u32 handle,
+ bool wait_all, unsigned long timeout)
+{
+ long ret;
+ struct drm_gem_object *obj;
+
+ obj = drm_gem_object_lookup(filep, handle);
+ if (!obj) {
+ DRM_DEBUG("Failed to look up GEM BO %d\n", handle);
+ return -EINVAL;
+ }
+
+ ret = reservation_object_wait_timeout_rcu(obj->resv, wait_all,
+ true, timeout);
+ if (ret == 0)
+ ret = -ETIME;
+ else if (ret > 0)
+ ret = 0;
+
+ drm_gem_object_put_unlocked(obj);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_gem_reservation_object_wait);
+
/**
* drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
* @dev: drm_device
@@ -821,6 +863,7 @@ drm_gem_object_release(struct drm_gem_object *obj)
if (obj->filp)
fput(obj->filp);
+ reservation_object_fini(&obj->_resv);
drm_gem_free_mmap_offset(obj);
}
EXPORT_SYMBOL(drm_gem_object_release);
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 231e3f6d5f41..dc079efb3b0f 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -504,6 +504,7 @@ struct dma_buf *drm_gem_prime_export(struct drm_device *dev,
.size = obj->size,
.flags = flags,
.priv = obj,
+ .resv = obj->resv,
};
if (dev->driver->gem_prime_res_obj)
diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index c95727425284..25f1ff2df464 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -35,6 +35,7 @@
*/
#include <linux/kref.h>
+#include <linux/reservation.h>
#include <drm/drm_vma_manager.h>
@@ -262,6 +263,24 @@ struct drm_gem_object {
*/
struct dma_buf_attachment *import_attach;
+ /**
+ * @resv:
+ *
+ * Pointer to reservation object associated with the this GEM object.
+ *
+ * Normally (@resv == &@_resv) except for imported GEM objects.
+ */
+ struct reservation_object *resv;
+
+ /**
+ * @_resv:
+ *
+ * A reservation object for this GEM object.
+ *
+ * This is unused for imported GEM objects.
+ */
+ struct reservation_object _resv;
+
/**
* @funcs:
*
@@ -363,6 +382,8 @@ void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
bool dirty, bool accessed);
struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
+long drm_gem_reservation_object_wait(struct drm_file *filep, u32 handle,
+ bool wait_all, unsigned long timeout);
int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
u32 handle, u64 *offset);
int drm_gem_dumb_destroy(struct drm_file *file,
--
2.19.1
