Add support in the OP-TEE backend driver for protected memory
allocation. The support is limited to only the SMC ABI and for secure
video buffers.
OP-TEE is probed for the range of protected physical memory and a
memory pool allocator is initialized if OP-TEE have support for such
memory.
Signed-off-by: Jens Wiklander <jens.wiklan...@linaro.org>
Reviewed-by: Sumit Garg <sumit.g...@oss.qualcomm.com>
---
drivers/tee/optee/Kconfig | 5 +++
drivers/tee/optee/core.c | 7 ++++
drivers/tee/optee/optee_private.h | 2 +
drivers/tee/optee/smc_abi.c | 69 ++++++++++++++++++++++++++++++-
4 files changed, 81 insertions(+), 2 deletions(-)
diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig
index 7bb7990d0b07..50d2051f7f20 100644
--- a/drivers/tee/optee/Kconfig
+++ b/drivers/tee/optee/Kconfig
@@ -25,3 +25,8 @@ config OPTEE_INSECURE_LOAD_IMAGE
Additional documentation on kernel security risks are at
Documentation/tee/op-tee.rst.
+
+config OPTEE_STATIC_PROTMEM_POOL
+ bool
+ depends on HAS_IOMEM && TEE_DMABUF_HEAPS
+ default y
diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index c75fddc83576..49ccfe6f6583 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -56,6 +56,13 @@ int optee_rpmb_intf_rdev(struct notifier_block *intf,
unsigned long action,
return 0;
}
+int optee_set_dma_mask(struct optee *optee, u_int pa_width)
+{
+ u64 mask = DMA_BIT_MASK(min(64, pa_width));
+
+ return dma_coerce_mask_and_coherent(&optee->teedev->dev, mask);
+}
+
static void optee_bus_scan(struct work_struct *work)
{
WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
diff --git a/drivers/tee/optee/optee_private.h
b/drivers/tee/optee/optee_private.h
index 9526087f0e68..4969b83a9851 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -274,6 +274,8 @@ struct optee_call_ctx {
extern struct blocking_notifier_head optee_rpmb_intf_added;
+int optee_set_dma_mask(struct optee *optee, u_int pa_width);
+
int optee_notif_init(struct optee *optee, u_int max_key);
void optee_notif_uninit(struct optee *optee);
int optee_notif_wait(struct optee *optee, u_int key, u32 timeout);
diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
index 26f8f7bbbe56..b4c007ed3b94 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -1583,6 +1583,68 @@ static inline int optee_load_fw(struct platform_device
*pdev,
}
#endif
+static struct tee_protmem_pool *static_protmem_pool_init(struct optee *optee)
+{
+#if IS_ENABLED(CONFIG_OPTEE_STATIC_PROTMEM_POOL)
+ union {
+ struct arm_smccc_res smccc;
+ struct optee_smc_get_protmem_config_result result;
+ } res;
+ struct tee_protmem_pool *pool;
+ void *p;
+ int rc;
+
+ optee->smc.invoke_fn(OPTEE_SMC_GET_PROTMEM_CONFIG, 0, 0, 0, 0,
+ 0, 0, 0, &res.smccc);
+ if (res.result.status != OPTEE_SMC_RETURN_OK)
+ return ERR_PTR(-EINVAL);
+
+ rc = optee_set_dma_mask(optee, res.result.pa_width);
+ if (rc)
+ return ERR_PTR(rc);
+
+ /*
+ * Map the memory as uncached to make sure the kernel can work with
+ * __pfn_to_page() and friends since that's needed when passing the
+ * protected DMA-buf to a device. The memory should otherwise not
+ * be touched by the kernel since it's likely to cause an external
+ * abort due to the protection status.
+ */
+ p = devm_memremap(&optee->teedev->dev, res.result.start,
+ res.result.size, MEMREMAP_WC);
+ if (IS_ERR(p))
+ return p;
+
+ pool = tee_protmem_static_pool_alloc(res.result.start, res.result.size);
+ if (IS_ERR(pool))
+ devm_memunmap(&optee->teedev->dev, p);
+
+ return pool;
+#else
+ return ERR_PTR(-EINVAL);
+#endif
+}
+
+static int optee_protmem_pool_init(struct optee *optee)
+{
+ enum tee_dma_heap_id heap_id = TEE_DMA_HEAP_SECURE_VIDEO_PLAY;
+ struct tee_protmem_pool *pool = ERR_PTR(-EINVAL);
+ int rc;
+
+ if (!(optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_PROTMEM))
+ return 0;
+
+ pool = static_protmem_pool_init(optee);
+ if (IS_ERR(pool))
+ return PTR_ERR(pool);
+
+ rc = tee_device_register_dma_heap(optee->teedev, heap_id, pool);
+ if (rc)
+ pool->ops->destroy_pool(pool);
+
+ return rc;
+}
+
static int optee_probe(struct platform_device *pdev)
{
optee_invoke_fn *invoke_fn;
@@ -1678,7 +1740,7 @@ static int optee_probe(struct platform_device *pdev)
optee = kzalloc(sizeof(*optee), GFP_KERNEL);
if (!optee) {
rc = -ENOMEM;
- goto err_free_pool;
+ goto err_free_shm_pool;
}
optee->ops = &optee_ops;
@@ -1751,6 +1813,9 @@ static int optee_probe(struct platform_device *pdev)
pr_info("Asynchronous notifications enabled\n");
}
+ if (optee_protmem_pool_init(optee))
+ pr_info("Protected memory service not available\n");
+
/*
* Ensure that there are no pre-existing shm objects before enabling
* the shm cache so that there's no chance of receiving an invalid
@@ -1802,7 +1867,7 @@ static int optee_probe(struct platform_device *pdev)
tee_device_unregister(optee->teedev);
err_free_optee:
kfree(optee);
-err_free_pool:
+err_free_shm_pool:
tee_shm_pool_free(pool);
if (memremaped_shm)
memunmap(memremaped_shm);
--
2.43.0
