[Patch v2] tee: optee: Fix dynamic shm pool allocations

[Sumit Garg]

In case of dynamic shared memory pool, kernel memory allocated using
dmabuf_mgr pool needs to be registered with OP-TEE prior to its usage
during optee_open_session() or optee_invoke_func().

So fix dmabuf_mgr pool allocations via an additional call to
optee_shm_register().

Also, allow kernel pages to be registered as shared memory with OP-TEE.

Fixes: 9733b072a12a ("optee: allow to work without static shared memory")
Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxx>
---

Changes in v2:
Merge the dependency patch: https://lkml.org/lkml/2019/10/31/431

 drivers/tee/optee/call.c     |  7 +++++++
 drivers/tee/optee/shm_pool.c | 12 +++++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
index 13b0269..cf2367b 100644
--- a/drivers/tee/optee/call.c
+++ b/drivers/tee/optee/call.c
@@ -554,6 +554,13 @@ static int check_mem_type(unsigned long start, size_t num_pages)
 	struct mm_struct *mm = current->mm;
 	int rc;
 
+	/*
+	 * Allow kernel address to register with OP-TEE as kernel
+	 * pages are configured as normal memory only.
+	 */
+	if (virt_addr_valid(start))
+		return 0;
+
 	down_read(&mm->mmap_sem);
 	rc = __check_mem_type(find_vma(mm, start),
 			      start + num_pages * PAGE_SIZE);
diff --git a/drivers/tee/optee/shm_pool.c b/drivers/tee/optee/shm_pool.c
index de1d9b8..0332a53 100644
--- a/drivers/tee/optee/shm_pool.c
+++ b/drivers/tee/optee/shm_pool.c
@@ -17,6 +17,7 @@ static int pool_op_alloc(struct tee_shm_pool_mgr *poolm,
 {
 	unsigned int order = get_order(size);
 	struct page *page;
+	int rc = 0;
 
 	page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
 	if (!page)
@@ -26,12 +27,21 @@ static int pool_op_alloc(struct tee_shm_pool_mgr *poolm,
 	shm->paddr = page_to_phys(page);
 	shm->size = PAGE_SIZE << order;
 
-	return 0;
+	if (shm->flags & TEE_SHM_DMA_BUF) {
+		shm->flags |= TEE_SHM_REGISTER;
+		rc = optee_shm_register(shm->ctx, shm, &page, 1 << order,
+					(unsigned long)shm->kaddr);
+	}
+
+	return rc;
 }
 
 static void pool_op_free(struct tee_shm_pool_mgr *poolm,
 			 struct tee_shm *shm)
 {
+	if (shm->flags & TEE_SHM_DMA_BUF)
+		optee_shm_unregister(shm->ctx, shm);
+
 	free_pages((unsigned long)shm->kaddr, get_order(shm->size));
 	shm->kaddr = NULL;
 }
-- 
2.7.4