tee: add tee_shm_register_{user,kernel}_buf()

Adds the two new functions tee_shm_register_user_buf() and
tee_shm_register_kernel_buf() which should be used instead of the old
tee_shm_register().

This avoids having the caller supplying the flags parameter which
exposes a bit more than desired of the internals of the TEE subsystem.

Reviewed-by: Sumit Garg <[e-mail]>
Signed-off-by: Jens Wiklander <[e-mail]>

drivers/tee/tee_core.c

···
 	if (data.flags)
 		return -EINVAL;
 
-	shm = tee_shm_register(ctx, data.addr, data.length,
-			       TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED);
+	shm = tee_shm_register_user_buf(ctx, data.addr, data.length);
 	if (IS_ERR(shm))
 		return PTR_ERR(shm);
 

drivers/tee/tee_private.h

···
 void teedev_ctx_put(struct tee_context *ctx);
 
 struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size);
+struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx,
+					  unsigned long addr, size_t length);
 
 #endif /*TEE_PRIVATE_H*/

drivers/tee/tee_shm.c

···
 }
 EXPORT_SYMBOL_GPL(tee_shm_register);
 
+/**
+ * tee_shm_register_user_buf() - Register a userspace shared memory buffer
+ * @ctx:	Context that registers the shared memory
+ * @addr:	The userspace address of the shared buffer
+ * @length:	Length of the shared buffer
+ *
+ * @returns a pointer to 'struct tee_shm'
+ */
+struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx,
+					  unsigned long addr, size_t length)
+{
+	return tee_shm_register(ctx, addr, length,
+				TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED);
+}
+
+/**
+ * tee_shm_register_kernel_buf() - Register kernel memory to be shared with
+ *				   secure world
+ * @ctx:	Context that registers the shared memory
+ * @addr:	The buffer
+ * @length:	Length of the buffer
+ *
+ * @returns a pointer to 'struct tee_shm'
+ */
+
+struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx,
+					    void *addr, size_t length)
+{
+	return tee_shm_register(ctx, (unsigned long)addr, length,
+				TEE_SHM_DMA_BUF | TEE_SHM_KERNEL_MAPPED);
+}
+EXPORT_SYMBOL_GPL(tee_shm_register_kernel_buf);
+
 static int tee_shm_fop_release(struct inode *inode, struct file *filp)
 {
 	tee_shm_put(filp->private_data);

include/linux/tee_drv.h

···
  */
 struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
 				 size_t length, u32 flags);
+struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx,
+					    void *addr, size_t length);
 
 /**
  * tee_shm_is_registered() - Check if shared memory object in registered in TEE