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-rw-r--r--drivers/tee/optee/supp.c382
1 files changed, 382 insertions, 0 deletions
diff --git a/drivers/tee/optee/supp.c b/drivers/tee/optee/supp.c
new file mode 100644
index 000000000..322a543b8
--- /dev/null
+++ b/drivers/tee/optee/supp.c
@@ -0,0 +1,382 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2015, Linaro Limited
+ */
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include "optee_private.h"
+
+struct optee_supp_req {
+ struct list_head link;
+
+ bool in_queue;
+ u32 func;
+ u32 ret;
+ size_t num_params;
+ struct tee_param *param;
+
+ struct completion c;
+};
+
+void optee_supp_init(struct optee_supp *supp)
+{
+ memset(supp, 0, sizeof(*supp));
+ mutex_init(&supp->mutex);
+ init_completion(&supp->reqs_c);
+ idr_init(&supp->idr);
+ INIT_LIST_HEAD(&supp->reqs);
+ supp->req_id = -1;
+}
+
+void optee_supp_uninit(struct optee_supp *supp)
+{
+ mutex_destroy(&supp->mutex);
+ idr_destroy(&supp->idr);
+}
+
+void optee_supp_release(struct optee_supp *supp)
+{
+ int id;
+ struct optee_supp_req *req;
+ struct optee_supp_req *req_tmp;
+
+ mutex_lock(&supp->mutex);
+
+ /* Abort all request retrieved by supplicant */
+ idr_for_each_entry(&supp->idr, req, id) {
+ idr_remove(&supp->idr, id);
+ req->ret = TEEC_ERROR_COMMUNICATION;
+ complete(&req->c);
+ }
+
+ /* Abort all queued requests */
+ list_for_each_entry_safe(req, req_tmp, &supp->reqs, link) {
+ list_del(&req->link);
+ req->in_queue = false;
+ req->ret = TEEC_ERROR_COMMUNICATION;
+ complete(&req->c);
+ }
+
+ supp->ctx = NULL;
+ supp->req_id = -1;
+
+ mutex_unlock(&supp->mutex);
+}
+
+/**
+ * optee_supp_thrd_req() - request service from supplicant
+ * @ctx: context doing the request
+ * @func: function requested
+ * @num_params: number of elements in @param array
+ * @param: parameters for function
+ *
+ * Returns result of operation to be passed to secure world
+ */
+u32 optee_supp_thrd_req(struct tee_context *ctx, u32 func, size_t num_params,
+ struct tee_param *param)
+
+{
+ struct optee *optee = tee_get_drvdata(ctx->teedev);
+ struct optee_supp *supp = &optee->supp;
+ struct optee_supp_req *req;
+ bool interruptable;
+ u32 ret;
+
+ /*
+ * Return in case there is no supplicant available and
+ * non-blocking request.
+ */
+ if (!supp->ctx && ctx->supp_nowait)
+ return TEEC_ERROR_COMMUNICATION;
+
+ req = kzalloc(sizeof(*req), GFP_KERNEL);
+ if (!req)
+ return TEEC_ERROR_OUT_OF_MEMORY;
+
+ init_completion(&req->c);
+ req->func = func;
+ req->num_params = num_params;
+ req->param = param;
+
+ /* Insert the request in the request list */
+ mutex_lock(&supp->mutex);
+ list_add_tail(&req->link, &supp->reqs);
+ req->in_queue = true;
+ mutex_unlock(&supp->mutex);
+
+ /* Tell an eventual waiter there's a new request */
+ complete(&supp->reqs_c);
+
+ /*
+ * Wait for supplicant to process and return result, once we've
+ * returned from wait_for_completion(&req->c) successfully we have
+ * exclusive access again.
+ */
+ while (wait_for_completion_interruptible(&req->c)) {
+ mutex_lock(&supp->mutex);
+ interruptable = !supp->ctx;
+ if (interruptable) {
+ /*
+ * There's no supplicant available and since the
+ * supp->mutex currently is held none can
+ * become available until the mutex released
+ * again.
+ *
+ * Interrupting an RPC to supplicant is only
+ * allowed as a way of slightly improving the user
+ * experience in case the supplicant hasn't been
+ * started yet. During normal operation the supplicant
+ * will serve all requests in a timely manner and
+ * interrupting then wouldn't make sense.
+ */
+ if (req->in_queue) {
+ list_del(&req->link);
+ req->in_queue = false;
+ }
+ }
+ mutex_unlock(&supp->mutex);
+
+ if (interruptable) {
+ req->ret = TEEC_ERROR_COMMUNICATION;
+ break;
+ }
+ }
+
+ ret = req->ret;
+ kfree(req);
+
+ return ret;
+}
+
+static struct optee_supp_req *supp_pop_entry(struct optee_supp *supp,
+ int num_params, int *id)
+{
+ struct optee_supp_req *req;
+
+ if (supp->req_id != -1) {
+ /*
+ * Supplicant should not mix synchronous and asnynchronous
+ * requests.
+ */
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (list_empty(&supp->reqs))
+ return NULL;
+
+ req = list_first_entry(&supp->reqs, struct optee_supp_req, link);
+
+ if (num_params < req->num_params) {
+ /* Not enough room for parameters */
+ return ERR_PTR(-EINVAL);
+ }
+
+ *id = idr_alloc(&supp->idr, req, 1, 0, GFP_KERNEL);
+ if (*id < 0)
+ return ERR_PTR(-ENOMEM);
+
+ list_del(&req->link);
+ req->in_queue = false;
+
+ return req;
+}
+
+static int supp_check_recv_params(size_t num_params, struct tee_param *params,
+ size_t *num_meta)
+{
+ size_t n;
+
+ if (!num_params)
+ return -EINVAL;
+
+ /*
+ * If there's memrefs we need to decrease those as they where
+ * increased earlier and we'll even refuse to accept any below.
+ */
+ for (n = 0; n < num_params; n++)
+ if (tee_param_is_memref(params + n) && params[n].u.memref.shm)
+ tee_shm_put(params[n].u.memref.shm);
+
+ /*
+ * We only expect parameters as TEE_IOCTL_PARAM_ATTR_TYPE_NONE with
+ * or without the TEE_IOCTL_PARAM_ATTR_META bit set.
+ */
+ for (n = 0; n < num_params; n++)
+ if (params[n].attr &&
+ params[n].attr != TEE_IOCTL_PARAM_ATTR_META)
+ return -EINVAL;
+
+ /* At most we'll need one meta parameter so no need to check for more */
+ if (params->attr == TEE_IOCTL_PARAM_ATTR_META)
+ *num_meta = 1;
+ else
+ *num_meta = 0;
+
+ return 0;
+}
+
+/**
+ * optee_supp_recv() - receive request for supplicant
+ * @ctx: context receiving the request
+ * @func: requested function in supplicant
+ * @num_params: number of elements allocated in @param, updated with number
+ * used elements
+ * @param: space for parameters for @func
+ *
+ * Returns 0 on success or <0 on failure
+ */
+int optee_supp_recv(struct tee_context *ctx, u32 *func, u32 *num_params,
+ struct tee_param *param)
+{
+ struct tee_device *teedev = ctx->teedev;
+ struct optee *optee = tee_get_drvdata(teedev);
+ struct optee_supp *supp = &optee->supp;
+ struct optee_supp_req *req = NULL;
+ int id;
+ size_t num_meta;
+ int rc;
+
+ rc = supp_check_recv_params(*num_params, param, &num_meta);
+ if (rc)
+ return rc;
+
+ while (true) {
+ mutex_lock(&supp->mutex);
+ req = supp_pop_entry(supp, *num_params - num_meta, &id);
+ mutex_unlock(&supp->mutex);
+
+ if (req) {
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+ break;
+ }
+
+ /*
+ * If we didn't get a request we'll block in
+ * wait_for_completion() to avoid needless spinning.
+ *
+ * This is where supplicant will be hanging most of
+ * the time, let's make this interruptable so we
+ * can easily restart supplicant if needed.
+ */
+ if (wait_for_completion_interruptible(&supp->reqs_c))
+ return -ERESTARTSYS;
+ }
+
+ if (num_meta) {
+ /*
+ * tee-supplicant support meta parameters -> requsts can be
+ * processed asynchronously.
+ */
+ param->attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT |
+ TEE_IOCTL_PARAM_ATTR_META;
+ param->u.value.a = id;
+ param->u.value.b = 0;
+ param->u.value.c = 0;
+ } else {
+ mutex_lock(&supp->mutex);
+ supp->req_id = id;
+ mutex_unlock(&supp->mutex);
+ }
+
+ *func = req->func;
+ *num_params = req->num_params + num_meta;
+ memcpy(param + num_meta, req->param,
+ sizeof(struct tee_param) * req->num_params);
+
+ return 0;
+}
+
+static struct optee_supp_req *supp_pop_req(struct optee_supp *supp,
+ size_t num_params,
+ struct tee_param *param,
+ size_t *num_meta)
+{
+ struct optee_supp_req *req;
+ int id;
+ size_t nm;
+ const u32 attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT |
+ TEE_IOCTL_PARAM_ATTR_META;
+
+ if (!num_params)
+ return ERR_PTR(-EINVAL);
+
+ if (supp->req_id == -1) {
+ if (param->attr != attr)
+ return ERR_PTR(-EINVAL);
+ id = param->u.value.a;
+ nm = 1;
+ } else {
+ id = supp->req_id;
+ nm = 0;
+ }
+
+ req = idr_find(&supp->idr, id);
+ if (!req)
+ return ERR_PTR(-ENOENT);
+
+ if ((num_params - nm) != req->num_params)
+ return ERR_PTR(-EINVAL);
+
+ idr_remove(&supp->idr, id);
+ supp->req_id = -1;
+ *num_meta = nm;
+
+ return req;
+}
+
+/**
+ * optee_supp_send() - send result of request from supplicant
+ * @ctx: context sending result
+ * @ret: return value of request
+ * @num_params: number of parameters returned
+ * @param: returned parameters
+ *
+ * Returns 0 on success or <0 on failure.
+ */
+int optee_supp_send(struct tee_context *ctx, u32 ret, u32 num_params,
+ struct tee_param *param)
+{
+ struct tee_device *teedev = ctx->teedev;
+ struct optee *optee = tee_get_drvdata(teedev);
+ struct optee_supp *supp = &optee->supp;
+ struct optee_supp_req *req;
+ size_t n;
+ size_t num_meta;
+
+ mutex_lock(&supp->mutex);
+ req = supp_pop_req(supp, num_params, param, &num_meta);
+ mutex_unlock(&supp->mutex);
+
+ if (IS_ERR(req)) {
+ /* Something is wrong, let supplicant restart. */
+ return PTR_ERR(req);
+ }
+
+ /* Update out and in/out parameters */
+ for (n = 0; n < req->num_params; n++) {
+ struct tee_param *p = req->param + n;
+
+ switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
+ case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
+ case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
+ p->u.value.a = param[n + num_meta].u.value.a;
+ p->u.value.b = param[n + num_meta].u.value.b;
+ p->u.value.c = param[n + num_meta].u.value.c;
+ break;
+ case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
+ case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
+ p->u.memref.size = param[n + num_meta].u.memref.size;
+ break;
+ default:
+ break;
+ }
+ }
+ req->ret = ret;
+
+ /* Let the requesting thread continue */
+ complete(&req->c);
+
+ return 0;
+}