tee: flexible shared memory pool creation

Makes creation of shm pools more flexible by adding new more primitive
functions to allocate a shm pool. This makes it easier to add driver
specific shm pool management.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index cb889afe576b..e9be4a45ff3e 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -150,6 +150,97 @@ int tee_device_register(struct tee_device *teedev);
 void tee_device_unregister(struct tee_device *teedev);
 
 /**
+ * struct tee_shm - shared memory object
+ * @teedev:	device used to allocate the object
+ * @ctx:	context using the object, if NULL the context is gone
+ * @link	link element
+ * @paddr:	physical address of the shared memory
+ * @kaddr:	virtual address of the shared memory
+ * @size:	size of shared memory
+ * @offset:	offset of buffer in user space
+ * @pages:	locked pages from userspace
+ * @num_pages:	number of locked pages
+ * @dmabuf:	dmabuf used to for exporting to user space
+ * @flags:	defined by TEE_SHM_* in tee_drv.h
+ * @id:		unique id of a shared memory object on this device
+ *
+ * This pool is only supposed to be accessed directly from the TEE
+ * subsystem and from drivers that implements their own shm pool manager.
+ */
+struct tee_shm {
+	struct tee_device *teedev;
+	struct tee_context *ctx;
+	struct list_head link;
+	phys_addr_t paddr;
+	void *kaddr;
+	size_t size;
+	unsigned int offset;
+	struct page **pages;
+	size_t num_pages;
+	struct dma_buf *dmabuf;
+	u32 flags;
+	int id;
+};
+
+/**
+ * struct tee_shm_pool_mgr - shared memory manager
+ * @ops:		operations
+ * @private_data:	private data for the shared memory manager
+ */
+struct tee_shm_pool_mgr {
+	const struct tee_shm_pool_mgr_ops *ops;
+	void *private_data;
+};
+
+/**
+ * struct tee_shm_pool_mgr_ops - shared memory pool manager operations
+ * @alloc:		called when allocating shared memory
+ * @free:		called when freeing shared memory
+ * @destroy_poolmgr:	called when destroying the pool manager
+ */
+struct tee_shm_pool_mgr_ops {
+	int (*alloc)(struct tee_shm_pool_mgr *poolmgr, struct tee_shm *shm,
+		     size_t size);
+	void (*free)(struct tee_shm_pool_mgr *poolmgr, struct tee_shm *shm);
+	void (*destroy_poolmgr)(struct tee_shm_pool_mgr *poolmgr);
+};
+
+/**
+ * tee_shm_pool_alloc() - Create a shared memory pool from shm managers
+ * @priv_mgr:	manager for driver private shared memory allocations
+ * @dmabuf_mgr:	manager for dma-buf shared memory allocations
+ *
+ * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied
+ * in @dmabuf, others will use the range provided by @priv.
+ *
+ * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
+ */
+struct tee_shm_pool *tee_shm_pool_alloc(struct tee_shm_pool_mgr *priv_mgr,
+					struct tee_shm_pool_mgr *dmabuf_mgr);
+
+/*
+ * tee_shm_pool_mgr_alloc_res_mem() - Create a shm manager for reserved
+ * memory
+ * @vaddr:	Virtual address of start of pool
+ * @paddr:	Physical address of start of pool
+ * @size:	Size in bytes of the pool
+ *
+ * @returns pointer to a 'struct tee_shm_pool_mgr' or an ERR_PTR on failure.
+ */
+struct tee_shm_pool_mgr *tee_shm_pool_mgr_alloc_res_mem(unsigned long vaddr,
+							phys_addr_t paddr,
+							size_t size,
+							int min_alloc_order);
+
+/**
+ * tee_shm_pool_mgr_destroy() - Free a shared memory manager
+ */
+static inline void tee_shm_pool_mgr_destroy(struct tee_shm_pool_mgr *poolm)
+{
+	poolm->ops->destroy_poolmgr(poolm);
+}
+
+/**
  * struct tee_shm_pool_mem_info - holds information needed to create a shared
  * memory pool
  * @vaddr:	Virtual address of start of pool