[PATCH v1 12/14] tee: optee: enable dynamic SHM support

From: Volodymyr Babchuk
Date: Fri Oct 13 2017 - 15:34:44 EST


From: Volodymyr Babchuk <vlad.babchuk@xxxxxxxxx>

Previous patches added various features that are needed for dynamic SHM.
Dynamic SHM allows Normal World to share any buffers with OP-TEE.
While original design suggested to use pre-allocated region (usually of
1M to 2M of size), this new approach allows to use all non-secure RAM for
command buffers, RPC allocations and TA parameters.

This patch checks capability OPTEE_SMC_SEC_CAP_DYNAMIC_SHM. If it was set
by OP-TEE, then kernel part of OP-TEE will use kernel page allocator
to allocate command buffers. Also it will set TEE_GEN_CAP_REG_MEM
capability to tell userspace that it supports shared memory registration.

Signed-off-by: Volodymyr Babchuk <vlad.babchuk@xxxxxxxxx>
---
drivers/tee/optee/core.c | 69 +++++++++++++++++++++++++++++++++++-------------
1 file changed, 51 insertions(+), 18 deletions(-)

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index dbe5a61..51d5575 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -28,6 +28,7 @@
#include <linux/uaccess.h>
#include "optee_private.h"
#include "optee_smc.h"
+#include "shm_pool.h"

#define DRIVER_NAME "optee"

@@ -219,6 +220,10 @@ static void optee_get_version(struct tee_device *teedev,
.impl_caps = TEE_OPTEE_CAP_TZ,
.gen_caps = TEE_GEN_CAP_GP,
};
+ struct optee *optee = tee_get_drvdata(teedev);
+
+ if (optee->sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
+ v.gen_caps |= TEE_GEN_CAP_REG_MEM;
*vers = v;
}

@@ -397,21 +402,22 @@ static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
}

static struct tee_shm_pool *
-optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm)
+optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm,
+ u32 sec_caps)
{
union {
struct arm_smccc_res smccc;
struct optee_smc_get_shm_config_result result;
} res;
- struct tee_shm_pool *pool;
unsigned long vaddr;
phys_addr_t paddr;
size_t size;
phys_addr_t begin;
phys_addr_t end;
void *va;
- struct tee_shm_pool_mem_info priv_info;
- struct tee_shm_pool_mem_info dmabuf_info;
+ struct tee_shm_pool_mgr *priv_mgr;
+ struct tee_shm_pool_mgr *dmabuf_mgr;
+ void *rc;

invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
if (res.result.status != OPTEE_SMC_RETURN_OK) {
@@ -441,22 +447,49 @@ optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm)
}
vaddr = (unsigned long)va;

- priv_info.vaddr = vaddr;
- priv_info.paddr = paddr;
- priv_info.size = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
- dmabuf_info.vaddr = vaddr + OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
- dmabuf_info.paddr = paddr + OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
- dmabuf_info.size = size - OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
-
- pool = tee_shm_pool_alloc_res_mem(&priv_info, &dmabuf_info);
- if (IS_ERR(pool)) {
- memunmap(va);
- goto out;
+ /*
+ * If OP-TEE can work with unregistered SHM, we will use own pool
+ * for private shm
+ */
+ if (sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM) {
+ rc = optee_shm_pool_alloc_pages();
+ if (IS_ERR(rc))
+ goto err_memunmap;
+ priv_mgr = rc;
+ } else {
+ const size_t sz = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
+
+ rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, sz,
+ 3 /* 8 bytes aligned */);
+ if (IS_ERR(rc))
+ goto err_memunmap;
+ priv_mgr = rc;
+
+ vaddr += sz;
+ paddr += sz;
+ size -= sz;
}

+ rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, size, PAGE_SHIFT);
+ if (IS_ERR(rc))
+ goto err_free_priv_mgr;
+ dmabuf_mgr = rc;
+
+ rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
+ if (IS_ERR(rc))
+ goto err_free_dmabuf_mgr;
+
*memremaped_shm = va;
-out:
- return pool;
+
+ return rc;
+
+err_free_dmabuf_mgr:
+ tee_shm_pool_mgr_destroy(dmabuf_mgr);
+err_free_priv_mgr:
+ tee_shm_pool_mgr_destroy(priv_mgr);
+err_memunmap:
+ memunmap(va);
+ return rc;
}

/* Simple wrapper functions to be able to use a function pointer */
@@ -534,7 +567,7 @@ static struct optee *optee_probe(struct device_node *np)
if (!(sec_caps & OPTEE_SMC_SEC_CAP_HAVE_RESERVED_SHM))
return ERR_PTR(-EINVAL);

- pool = optee_config_shm_memremap(invoke_fn, &memremaped_shm);
+ pool = optee_config_shm_memremap(invoke_fn, &memremaped_shm, sec_caps);
if (IS_ERR(pool))
return (void *)pool;

--
2.7.4