embox

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/**
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 * @file
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 *
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 * @date Jan 19, 2018
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 * @author Anton Bondarev
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 */
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#include <util/log.h>
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#include <stdint.h>
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#include <pthread.h>
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#include <linux/idr.h>
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#include <linux/pagemap.h>
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#include <embox_drm/drm_gem.h>
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#include <embox_drm/drm_priv.h>
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/**
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 * drm_gem_object_lookup - look up a GEM object from it's handle
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 * @filp: DRM file private date
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 * @handle: userspace handle
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 *
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 * Returns:
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 *
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 * A reference to the object named by the handle if such exists on @filp, NULL
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 * otherwise.
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 */
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struct drm_gem_object *
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drm_gem_object_lookup(struct drm_file *filp, uint32_t handle) {
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	struct drm_gem_object *obj;
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	pthread_mutex_lock(&filp->table_lock);
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	obj = idr_find(&filp->object_idr, handle);
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	pthread_mutex_unlock(&filp->table_lock);
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	return obj;
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}
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/**
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 * drm_gem_handle_create_tail - internal functions to create a handle
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 * @file_priv: drm file-private structure to register the handle for
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 * @obj: object to register
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 * @handlep: pointer to return the created handle to the caller
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 *
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 * This expects the dev->object_name_lock to be held already and will drop it
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 * before returning. Used to avoid races in establishing new handles when
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 * importing an object from either an flink name or a dma-buf.
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 *
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 * Handles must be release again through drm_gem_handle_delete(). This is done
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 * when userspace closes @file_priv for all attached handles, or through the
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 * GEM_CLOSE ioctl for individual handles.
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 */
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int drm_gem_handle_create_tail(struct drm_file *file_priv,
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			   struct drm_gem_object *obj,
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			   uint32_t *handlep) {
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	int ret;
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	obj->handle_count++;
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	pthread_mutex_lock(&file_priv->table_lock);
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	ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
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	if (ret < 0) {
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		return ret;
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	}
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	pthread_mutex_unlock(&file_priv->table_lock);
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	*handlep = ret;
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	return 0;
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}
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/**
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 * drm_gem_handle_create - create a gem handle for an object
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 * @file_priv: drm file-private structure to register the handle for
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 * @obj: object to register
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 * @handlep: pionter to return the created handle to the caller
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 *
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 * Create a handle for this object. This adds a handle reference
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 * to the object, which includes a regular reference count. Callers
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 * will likely want to dereference the object afterwards.
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 */
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int drm_gem_handle_create(struct drm_file *file_priv,
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			  struct drm_gem_object *obj,
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			  uint32_t *handlep) {
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	return drm_gem_handle_create_tail(file_priv, obj, handlep);
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}
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/**
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 * drm_gem_object_init - initialize an allocated shmem-backed GEM object
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 * @dev: drm_device the object should be initialized for
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 * @obj: drm_gem_object to initialize
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 * @size: object size
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 *
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 * Initialize an already allocated GEM object of the specified size with
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 * shmfs backing store.
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 */
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int drm_gem_object_init(struct drm_device *dev,
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			struct drm_gem_object *obj, size_t size) {
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	*obj = (struct drm_gem_object) {
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		.dev  = dev,
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		.size = size,
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	};
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	return 0;
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}
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