1 files changed, 107 insertions, 51 deletions

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 03bd3c7bd0dc..21809a82187b 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -37,10 +37,11 @@
 #include <drm/drm_framebuffer.h>
 #include <drm/drm_gem.h>
 #include <drm/drm_prime.h>
+#include <drm/drm_print.h>
 
 #include "drm_internal.h"
 
-MODULE_IMPORT_NS(DMA_BUF);
+MODULE_IMPORT_NS("DMA_BUF");
 
 /**
  * DOC: overview and lifetime rules
@@ -93,7 +94,7 @@ struct drm_prime_member {
 	struct rb_node handle_rb;
 };
 
-static int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
+int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
 				    struct dma_buf *dma_buf, uint32_t handle)
 {
 	struct drm_prime_member *member;
@@ -190,8 +191,6 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
 {
 	struct rb_node *rb;
 
-	mutex_lock(&prime_fpriv->lock);
-
 	rb = prime_fpriv->handles.rb_node;
 	while (rb) {
 		struct drm_prime_member *member;
@@ -210,8 +209,6 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
 			rb = rb->rb_left;
 		}
 	}
-
-	mutex_unlock(&prime_fpriv->lock);
 }
 
 void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv)
@@ -410,22 +407,30 @@ static struct dma_buf *export_and_register_object(struct drm_device *dev,
 }
 
 /**
- * drm_gem_prime_handle_to_fd - PRIME export function for GEM drivers
+ * drm_gem_prime_handle_to_dmabuf - PRIME export function for GEM drivers
  * @dev: dev to export the buffer from
  * @file_priv: drm file-private structure
  * @handle: buffer handle to export
  * @flags: flags like DRM_CLOEXEC
- * @prime_fd: pointer to storage for the fd id of the create dma-buf
  *
  * This is the PRIME export function which must be used mandatorily by GEM
  * drivers to ensure correct lifetime management of the underlying GEM object.
  * The actual exporting from GEM object to a dma-buf is done through the
  * &drm_gem_object_funcs.export callback.
+ *
+ * Unlike drm_gem_prime_handle_to_fd(), it returns the struct dma_buf it
+ * has created, without attaching it to any file descriptors.  The difference
+ * between those two is similar to that between anon_inode_getfile() and
+ * anon_inode_getfd(); insertion into descriptor table is something you
+ * can not revert if any cleanup is needed, so the descriptor-returning
+ * variants should only be used when you are past the last failure exit
+ * and the only thing left is passing the new file descriptor to userland.
+ * When all you need is the object itself or when you need to do something
+ * else that might fail, use that one instead.
  */
-int drm_gem_prime_handle_to_fd(struct drm_device *dev,
+struct dma_buf *drm_gem_prime_handle_to_dmabuf(struct drm_device *dev,
 			       struct drm_file *file_priv, uint32_t handle,
-			       uint32_t flags,
-			       int *prime_fd)
+			       uint32_t flags)
 {
 	struct drm_gem_object *obj;
 	int ret = 0;
@@ -434,14 +439,14 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev,
 	mutex_lock(&file_priv->prime.lock);
 	obj = drm_gem_object_lookup(file_priv, handle);
 	if (!obj)  {
-		ret = -ENOENT;
+		dmabuf = ERR_PTR(-ENOENT);
 		goto out_unlock;
 	}
 
 	dmabuf = drm_prime_lookup_buf_by_handle(&file_priv->prime, handle);
 	if (dmabuf) {
 		get_dma_buf(dmabuf);
-		goto out_have_handle;
+		goto out;
 	}
 
 	mutex_lock(&dev->object_name_lock);
@@ -463,7 +468,6 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev,
 		/* normally the created dma-buf takes ownership of the ref,
 		 * but if that fails then drop the ref
 		 */
-		ret = PTR_ERR(dmabuf);
 		mutex_unlock(&dev->object_name_lock);
 		goto out;
 	}
@@ -478,34 +482,51 @@ out_have_obj:
 	ret = drm_prime_add_buf_handle(&file_priv->prime,
 				       dmabuf, handle);
 	mutex_unlock(&dev->object_name_lock);
-	if (ret)
-		goto fail_put_dmabuf;
-
-out_have_handle:
-	ret = dma_buf_fd(dmabuf, flags);
-	/*
-	 * We must _not_ remove the buffer from the handle cache since the newly
-	 * created dma buf is already linked in the global obj->dma_buf pointer,
-	 * and that is invariant as long as a userspace gem handle exists.
-	 * Closing the handle will clean out the cache anyway, so we don't leak.
-	 */
-	if (ret < 0) {
-		goto fail_put_dmabuf;
-	} else {
-		*prime_fd = ret;
-		ret = 0;
+	if (ret) {
+		dma_buf_put(dmabuf);
+		dmabuf = ERR_PTR(ret);
 	}
-
-	goto out;
-
-fail_put_dmabuf:
-	dma_buf_put(dmabuf);
 out:
 	drm_gem_object_put(obj);
 out_unlock:
 	mutex_unlock(&file_priv->prime.lock);
+	return dmabuf;
+}
+EXPORT_SYMBOL(drm_gem_prime_handle_to_dmabuf);
 
-	return ret;
+/**
+ * drm_gem_prime_handle_to_fd - PRIME export function for GEM drivers
+ * @dev: dev to export the buffer from
+ * @file_priv: drm file-private structure
+ * @handle: buffer handle to export
+ * @flags: flags like DRM_CLOEXEC
+ * @prime_fd: pointer to storage for the fd id of the create dma-buf
+ *
+ * This is the PRIME export function which must be used mandatorily by GEM
+ * drivers to ensure correct lifetime management of the underlying GEM object.
+ * The actual exporting from GEM object to a dma-buf is done through the
+ * &drm_gem_object_funcs.export callback.
+ */
+int drm_gem_prime_handle_to_fd(struct drm_device *dev,
+			       struct drm_file *file_priv, uint32_t handle,
+			       uint32_t flags,
+			       int *prime_fd)
+{
+	struct dma_buf *dmabuf;
+	int fd = get_unused_fd_flags(flags);
+
+	if (fd < 0)
+		return fd;
+
+	dmabuf = drm_gem_prime_handle_to_dmabuf(dev, file_priv, handle, flags);
+	if (IS_ERR(dmabuf)) {
+		put_unused_fd(fd);
+		return PTR_ERR(dmabuf);
+	}
+
+	fd_install(fd, dmabuf->file);
+	*prime_fd = fd;
+	return 0;
 }
 EXPORT_SYMBOL(drm_gem_prime_handle_to_fd);
 
@@ -581,6 +602,7 @@ int drm_gem_map_attach(struct dma_buf *dma_buf,
 		       struct dma_buf_attachment *attach)
 {
 	struct drm_gem_object *obj = dma_buf->priv;
+	int ret;
 
 	/*
 	 * drm_gem_map_dma_buf() requires obj->get_sg_table(), but drivers
@@ -590,7 +612,16 @@ int drm_gem_map_attach(struct dma_buf *dma_buf,
 	    !obj->funcs->get_sg_table)
 		return -ENOSYS;
 
-	return drm_gem_pin(obj);
+	if (!obj->funcs->pin)
+		return 0;
+
+	ret = dma_resv_lock(obj->resv, NULL);
+	if (ret)
+		return ret;
+	ret = obj->funcs->pin(obj);
+	dma_resv_unlock(obj->resv);
+
+	return ret;
 }
 EXPORT_SYMBOL(drm_gem_map_attach);
 
@@ -607,8 +638,16 @@ void drm_gem_map_detach(struct dma_buf *dma_buf,
 			struct dma_buf_attachment *attach)
 {
 	struct drm_gem_object *obj = dma_buf->priv;
+	int ret;
 
-	drm_gem_unpin(obj);
+	if (!obj->funcs->unpin)
+		return;
+
+	ret = dma_resv_lock(obj->resv, NULL);
+	if (drm_WARN_ON(obj->dev, ret))
+		return;
+	obj->funcs->unpin(obj);
+	dma_resv_unlock(obj->resv);
 }
 EXPORT_SYMBOL(drm_gem_map_detach);
 
@@ -689,7 +728,7 @@ int drm_gem_dmabuf_vmap(struct dma_buf *dma_buf, struct iosys_map *map)
 {
 	struct drm_gem_object *obj = dma_buf->priv;
 
-	return drm_gem_vmap(obj, map);
+	return drm_gem_vmap_locked(obj, map);
 }
 EXPORT_SYMBOL(drm_gem_dmabuf_vmap);
 
@@ -705,7 +744,7 @@ void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, struct iosys_map *map)
 {
 	struct drm_gem_object *obj = dma_buf->priv;
 
-	drm_gem_vunmap(obj, map);
+	drm_gem_vunmap_locked(obj, map);
 }
 EXPORT_SYMBOL(drm_gem_dmabuf_vunmap);
 
@@ -786,7 +825,6 @@ int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
 EXPORT_SYMBOL(drm_gem_dmabuf_mmap);
 
 static const struct dma_buf_ops drm_gem_prime_dmabuf_ops =  {
-	.cache_sgt_mapping = true,
 	.attach = drm_gem_map_attach,
 	.detach = drm_gem_map_detach,
 	.map_dma_buf = drm_gem_map_dma_buf,
@@ -893,6 +931,26 @@ struct dma_buf *drm_gem_prime_export(struct drm_gem_object *obj,
 }
 EXPORT_SYMBOL(drm_gem_prime_export);
 
+
+/**
+ * drm_gem_is_prime_exported_dma_buf -
+ * checks if the DMA-BUF was exported from a GEM object belonging to @dev.
+ * @dev: drm_device to check against
+ * @dma_buf: dma-buf object to import
+ *
+ * Return: true if the DMA-BUF was exported from a GEM object belonging
+ * to @dev, false otherwise.
+ */
+
+bool drm_gem_is_prime_exported_dma_buf(struct drm_device *dev,
+				       struct dma_buf *dma_buf)
+{
+	struct drm_gem_object *obj = dma_buf->priv;
+
+	return (dma_buf->ops == &drm_gem_prime_dmabuf_ops) && (obj->dev == dev);
+}
+EXPORT_SYMBOL(drm_gem_is_prime_exported_dma_buf);
+
 /**
  * drm_gem_prime_import_dev - core implementation of the import callback
  * @dev: drm_device to import into
@@ -916,16 +974,14 @@ struct drm_gem_object *drm_gem_prime_import_dev(struct drm_device *dev,
 	struct drm_gem_object *obj;
 	int ret;
 
-	if (dma_buf->ops == &drm_gem_prime_dmabuf_ops) {
+	if (drm_gem_is_prime_exported_dma_buf(dev, dma_buf)) {
+		/*
+		 * Importing dmabuf exported from our own gem increases
+		 * refcount on gem itself instead of f_count of dmabuf.
+		 */
 		obj = dma_buf->priv;
-		if (obj->dev == dev) {
-			/*
-			 * Importing dmabuf exported from our own gem increases
-			 * refcount on gem itself instead of f_count of dmabuf.
-			 */
-			drm_gem_object_get(obj);
-			return obj;
-		}
+		drm_gem_object_get(obj);
+		return obj;
 	}
 
 	if (!dev->driver->gem_prime_import_sg_table)
@@ -980,7 +1036,7 @@ EXPORT_SYMBOL(drm_gem_prime_import_dev);
 struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev,
 					    struct dma_buf *dma_buf)
 {
-	return drm_gem_prime_import_dev(dev, dma_buf, dev->dev);
+	return drm_gem_prime_import_dev(dev, dma_buf, drm_dev_dma_dev(dev));
 }
 EXPORT_SYMBOL(drm_gem_prime_import);