Merge tag 'tee-drv-dynamic-shm-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee into next/drivers

Pull "tee dynamic shm for v4.16" from Jens Wiklander:

This pull request enables dynamic shared memory support in the TEE
subsystem as a whole and in OP-TEE in particular.

Global Platform TEE specification [1] allows client applications
to register part of own memory as a shared buffer between
application and TEE. This allows fast zero-copy communication between
TEE and REE. But current implementation of TEE in Linux does not support
this feature.

Also, current implementation of OP-TEE transport uses fixed size
pre-shared buffer for all communications with OP-TEE OS. This is okay
in the most use cases. But this prevents use of OP-TEE in virtualized
environments, because:
 a) We can't share the same buffer between different virtual machines
 b) Physically contiguous memory as seen by VM can be non-contiguous
    in reality (and as seen by OP-TEE OS) due to second stage of
    MMU translation.
 c) Size of this pre-shared buffer is limited.

So, first part of this pull request adds generic register/unregister
interface to tee subsystem. The second part adds necessary features into
OP-TEE driver, so it can use not only static pre-shared buffer, but
whole RAM to communicate with OP-TEE OS.

This change is backwards compatible allowing older secure world or
user space to work with newer kernels and vice versa.

[1] https://www.globalplatform.org/specificationsdevice.asp

* tag 'tee-drv-dynamic-shm-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  tee: shm: inline tee_shm_get_id()
  tee: use reference counting for tee_context
  tee: optee: enable dynamic SHM support
  tee: optee: add optee-specific shared pool implementation
  tee: optee: store OP-TEE capabilities in private data
  tee: optee: add registered buffers handling into RPC calls
  tee: optee: add registered shared parameters handling
  tee: optee: add shared buffer registration functions
  tee: optee: add page list manipulation functions
  tee: optee: Update protocol definitions
  tee: shm: add page accessor functions
  tee: shm: add accessors for buffer size and page offset
  tee: add register user memory
  tee: flexible shared memory pool creation

1 files changed, 5 insertions, 55 deletions

diff --git a/drivers/tee/tee_private.h b/drivers/tee/tee_private.h
index 21cb6be8bce9..85d99d621603 100644
--- a/drivers/tee/tee_private.h
+++ b/drivers/tee/tee_private.h
@@ -21,68 +21,15 @@
 #include <linux/mutex.h>
 #include <linux/types.h>
 
-struct tee_device;
-
-/**
- * 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
- * @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
- */
-struct tee_shm {
-	struct tee_device *teedev;
-	struct tee_context *ctx;
-	struct list_head link;
-	phys_addr_t paddr;
-	void *kaddr;
-	size_t size;
-	struct dma_buf *dmabuf;
-	u32 flags;
-	int id;
-};
-
-struct tee_shm_pool_mgr;
-
-/**
- * struct tee_shm_pool_mgr_ops - shared memory pool manager operations
- * @alloc:	called when allocating shared memory
- * @free:	called when freeing shared memory
- */
-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);
-};
-
-/**
- * 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 - shared memory pool
  * @private_mgr:	pool manager for shared memory only between kernel
  *			and secure world
  * @dma_buf_mgr:	pool manager for shared memory exported to user space
- * @destroy:		called when destroying the pool
- * @private_data:	private data for the pool
  */
 struct tee_shm_pool {
-	struct tee_shm_pool_mgr private_mgr;
-	struct tee_shm_pool_mgr dma_buf_mgr;
-	void (*destroy)(struct tee_shm_pool *pool);
-	void *private_data;
+	struct tee_shm_pool_mgr *private_mgr;
+	struct tee_shm_pool_mgr *dma_buf_mgr;
 };
 
 #define TEE_DEVICE_FLAG_REGISTERED	0x1
@@ -126,4 +73,7 @@ int tee_shm_get_fd(struct tee_shm *shm);
 bool tee_device_get(struct tee_device *teedev);
 void tee_device_put(struct tee_device *teedev);
 
+void teedev_ctx_get(struct tee_context *ctx);
+void teedev_ctx_put(struct tee_context *ctx);
+
 #endif /*TEE_PRIVATE_H*/