[PATCH 3/3] optee: support asynchronous supplicant requests
Jens Wiklander
jens.wiklander at linaro.org
Wed Nov 8 04:47:52 PST 2017
Adds support for asynchronous supplicant requests, meaning that the
supplicant can process several requests in parallel or block in a
request for some time.
Acked-by: Etienne Carriere <etienne.carriere at linaro.org>
Tested-by: Etienne Carriere <etienne.carriere at linaro.org> (b2260 pager=y/n)
Signed-off-by: Jens Wiklander <jens.wiklander at linaro.org>
---
drivers/tee/optee/core.c | 11 +-
drivers/tee/optee/optee_private.h | 43 ++---
drivers/tee/optee/rpc.c | 4 +-
drivers/tee/optee/supp.c | 358 +++++++++++++++++++++++---------------
4 files changed, 243 insertions(+), 173 deletions(-)
diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index 7952357df9c8..b7492da92567 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -187,12 +187,12 @@ static int optee_open(struct tee_context *ctx)
if (teedev == optee->supp_teedev) {
bool busy = true;
- mutex_lock(&optee->supp.ctx_mutex);
+ mutex_lock(&optee->supp.mutex);
if (!optee->supp.ctx) {
busy = false;
optee->supp.ctx = ctx;
}
- mutex_unlock(&optee->supp.ctx_mutex);
+ mutex_unlock(&optee->supp.mutex);
if (busy) {
kfree(ctxdata);
return -EBUSY;
@@ -252,11 +252,8 @@ static void optee_release(struct tee_context *ctx)
ctx->data = NULL;
- if (teedev == optee->supp_teedev) {
- mutex_lock(&optee->supp.ctx_mutex);
- optee->supp.ctx = NULL;
- mutex_unlock(&optee->supp.ctx_mutex);
- }
+ if (teedev == optee->supp_teedev)
+ optee_supp_release(&optee->supp);
}
static const struct tee_driver_ops optee_ops = {
diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index c374cd594314..3e7da187acbe 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -53,36 +53,24 @@ struct optee_wait_queue {
* @ctx the context of current connected supplicant.
* if !NULL the supplicant device is available for use,
* else busy
- * @ctx_mutex: held while accessing @ctx
- * @func: supplicant function id to call
- * @ret: call return value
- * @num_params: number of elements in @param
- * @param: parameters for @func
- * @req_posted: if true, a request has been posted to the supplicant
- * @supp_next_send: if true, next step is for supplicant to send response
- * @thrd_mutex: held by the thread doing a request to supplicant
- * @supp_mutex: held by supplicant while operating on this struct
- * @data_to_supp: supplicant is waiting on this for next request
- * @data_from_supp: requesting thread is waiting on this to get the result
+ * @mutex: held while accessing content of this struct
+ * @req_id: current request id if supplicant is doing synchronous
+ * communication, else -1
+ * @reqs: queued request not yet retrieved by supplicant
+ * @idr: IDR holding all requests currently being processed
+ * by supplicant
+ * @reqs_c: completion used by supplicant when waiting for a
+ * request to be queued.
*/
struct optee_supp {
+ /* Serializes access to this struct */
+ struct mutex mutex;
struct tee_context *ctx;
- /* Serializes access of ctx */
- struct mutex ctx_mutex;
-
- u32 func;
- u32 ret;
- size_t num_params;
- struct tee_param *param;
-
- bool req_posted;
- bool supp_next_send;
- /* Serializes access to this struct for requesting thread */
- struct mutex thrd_mutex;
- /* Serializes access to this struct for supplicant threads */
- struct mutex supp_mutex;
- struct completion data_to_supp;
- struct completion data_from_supp;
+
+ int req_id;
+ struct list_head reqs;
+ struct idr idr;
+ struct completion reqs_c;
};
/**
@@ -142,6 +130,7 @@ int optee_supp_read(struct tee_context *ctx, void __user *buf, size_t len);
int optee_supp_write(struct tee_context *ctx, void __user *buf, size_t len);
void optee_supp_init(struct optee_supp *supp);
void optee_supp_uninit(struct optee_supp *supp);
+void optee_supp_release(struct optee_supp *supp);
int optee_supp_recv(struct tee_context *ctx, u32 *func, u32 *num_params,
struct tee_param *param);
diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
index cef417f4f4d2..c6df4317ca9f 100644
--- a/drivers/tee/optee/rpc.c
+++ b/drivers/tee/optee/rpc.c
@@ -192,10 +192,10 @@ static struct tee_shm *cmd_alloc_suppl(struct tee_context *ctx, size_t sz)
if (ret)
return ERR_PTR(-ENOMEM);
- mutex_lock(&optee->supp.ctx_mutex);
+ mutex_lock(&optee->supp.mutex);
/* Increases count as secure world doesn't have a reference */
shm = tee_shm_get_from_id(optee->supp.ctx, param.u.value.c);
- mutex_unlock(&optee->supp.ctx_mutex);
+ mutex_unlock(&optee->supp.mutex);
return shm;
}
diff --git a/drivers/tee/optee/supp.c b/drivers/tee/optee/supp.c
index 56aa8b929b8c..df35fc01fd3e 100644
--- a/drivers/tee/optee/supp.c
+++ b/drivers/tee/optee/supp.c
@@ -16,21 +16,61 @@
#include <linux/uaccess.h>
#include "optee_private.h"
+struct optee_supp_req {
+ struct list_head link;
+
+ bool busy;
+ 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->ctx_mutex);
- mutex_init(&supp->thrd_mutex);
- mutex_init(&supp->supp_mutex);
- init_completion(&supp->data_to_supp);
- init_completion(&supp->data_from_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->ctx_mutex);
- mutex_destroy(&supp->thrd_mutex);
- mutex_destroy(&supp->supp_mutex);
+ 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) {
+ req->busy = false;
+ 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->ret = TEEC_ERROR_COMMUNICATION;
+ complete(&req->c);
+ }
+
+ supp->ctx = NULL;
+ supp->req_id = -1;
+
+ mutex_unlock(&supp->mutex);
}
/**
@@ -44,53 +84,42 @@ void optee_supp_uninit(struct optee_supp *supp)
*/
u32 optee_supp_thrd_req(struct tee_context *ctx, u32 func, size_t num_params,
struct tee_param *param)
+
{
- bool interruptable;
struct optee *optee = tee_get_drvdata(ctx->teedev);
struct optee_supp *supp = &optee->supp;
+ struct optee_supp_req *req = kzalloc(sizeof(*req), GFP_KERNEL);
+ bool interruptable;
u32 ret;
- /*
- * Other threads blocks here until we've copied our answer from
- * supplicant.
- */
- while (mutex_lock_interruptible(&supp->thrd_mutex)) {
- /* See comment below on when the RPC can be interrupted. */
- mutex_lock(&supp->ctx_mutex);
- interruptable = !supp->ctx;
- mutex_unlock(&supp->ctx_mutex);
- if (interruptable)
- return TEEC_ERROR_COMMUNICATION;
- }
+ if (!req)
+ return TEEC_ERROR_OUT_OF_MEMORY;
- /*
- * We have exclusive access now since the supplicant at this
- * point is either doing a
- * wait_for_completion_interruptible(&supp->data_to_supp) or is in
- * userspace still about to do the ioctl() to enter
- * optee_supp_recv() below.
- */
+ init_completion(&req->c);
+ req->func = func;
+ req->num_params = num_params;
+ req->param = param;
- supp->func = func;
- supp->num_params = num_params;
- supp->param = param;
- supp->req_posted = true;
+ /* Insert the request in the request list */
+ mutex_lock(&supp->mutex);
+ list_add_tail(&req->link, &supp->reqs);
+ mutex_unlock(&supp->mutex);
- /* Let supplicant get the data */
- complete(&supp->data_to_supp);
+ /* 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(data_from_supp) we have
+ * returned from wait_for_completion(&req->c) successfully we have
* exclusive access again.
*/
- while (wait_for_completion_interruptible(&supp->data_from_supp)) {
- mutex_lock(&supp->ctx_mutex);
+ 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->ctx_mutex currently is held none can
+ * supp->mutex currently is held none can
* become available until the mutex released
* again.
*
@@ -101,28 +130,65 @@ u32 optee_supp_thrd_req(struct tee_context *ctx, u32 func, size_t num_params,
* will serve all requests in a timely manner and
* interrupting then wouldn't make sense.
*/
- supp->ret = TEEC_ERROR_COMMUNICATION;
- init_completion(&supp->data_to_supp);
+ interruptable = !req->busy;
+ if (!req->busy)
+ list_del(&req->link);
}
- mutex_unlock(&supp->ctx_mutex);
- if (interruptable)
+ mutex_unlock(&supp->mutex);
+
+ if (interruptable) {
+ req->ret = TEEC_ERROR_COMMUNICATION;
break;
+ }
}
- ret = supp->ret;
- supp->param = NULL;
- supp->req_posted = false;
-
- /* We're done, let someone else talk to the supplicant now. */
- mutex_unlock(&supp->thrd_mutex);
+ ret = req->ret;
+ kfree(req);
return ret;
}
-static int supp_check_recv_params(size_t num_params, struct tee_param *params)
+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->busy = true;
+
+ 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.
@@ -132,11 +198,20 @@ static int supp_check_recv_params(size_t num_params, struct tee_param *params)
tee_shm_put(params[n].u.memref.shm);
/*
- * We only expect parameters as TEE_IOCTL_PARAM_ATTR_TYPE_NONE (0).
+ * 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)
+ 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;
}
@@ -156,69 +231,99 @@ int optee_supp_recv(struct tee_context *ctx, u32 *func, u32 *num_params,
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);
+ rc = supp_check_recv_params(*num_params, param, &num_meta);
if (rc)
return rc;
- /*
- * In case two threads in one supplicant is calling this function
- * simultaneously we need to protect the data with a mutex which
- * we'll release before returning.
- */
- mutex_lock(&supp->supp_mutex);
+ 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 (supp->supp_next_send) {
/*
- * optee_supp_recv() has been called again without
- * a optee_supp_send() in between. Supplicant has
- * probably been restarted before it was able to
- * write back last result. Abort last request and
- * wait for a new.
+ * 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 (supp->req_posted) {
- supp->ret = TEEC_ERROR_COMMUNICATION;
- supp->supp_next_send = false;
- complete(&supp->data_from_supp);
- }
+ if (wait_for_completion_interruptible(&supp->reqs_c))
+ return -ERESTARTSYS;
}
- /*
- * 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->data_to_supp)) {
- rc = -ERESTARTSYS;
- goto out;
+ 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);
}
- /* We have exlusive access to the data */
+ *func = req->func;
+ *num_params = req->num_params + num_meta;
+ memcpy(param + num_meta, req->param,
+ sizeof(struct tee_param) * req->num_params);
- if (*num_params < supp->num_params) {
- /*
- * Not enough room for parameters, tell supplicant
- * it failed and abort last request.
- */
- supp->ret = TEEC_ERROR_COMMUNICATION;
- rc = -EINVAL;
- complete(&supp->data_from_supp);
- goto out;
+ 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;
}
- *func = supp->func;
- *num_params = supp->num_params;
- memcpy(param, supp->param,
- sizeof(struct tee_param) * supp->num_params);
+ req = idr_find(&supp->idr, id);
+ if (!req)
+ return ERR_PTR(-ENOENT);
+
+ if ((num_params - nm) != req->num_params)
+ return ERR_PTR(-EINVAL);
- /* Allow optee_supp_send() below to do its work */
- supp->supp_next_send = true;
+ req->busy = false;
+ idr_remove(&supp->idr, id);
+ supp->req_id = -1;
+ *num_meta = nm;
- rc = 0;
-out:
- mutex_unlock(&supp->supp_mutex);
- return rc;
+ return req;
}
/**
@@ -236,63 +341,42 @@ int optee_supp_send(struct tee_context *ctx, u32 ret, u32 num_params,
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;
- int rc = 0;
+ size_t num_meta;
- /*
- * We still have exclusive access to the data since that's how we
- * left it when returning from optee_supp_read().
- */
+ mutex_lock(&supp->mutex);
+ req = supp_pop_req(supp, num_params, param, &num_meta);
+ mutex_unlock(&supp->mutex);
- /* See comment on mutex in optee_supp_read() above */
- mutex_lock(&supp->supp_mutex);
-
- if (!supp->supp_next_send) {
- /*
- * Something strange is going on, supplicant shouldn't
- * enter optee_supp_send() in this state
- */
- rc = -ENOENT;
- goto out;
- }
-
- if (num_params != supp->num_params) {
- /*
- * Something is wrong, let supplicant restart. Next call to
- * optee_supp_recv() will give an error to the requesting
- * thread and release it.
- */
- rc = -EINVAL;
- goto out;
+ if (IS_ERR(req)) {
+ /* Something is wrong, let supplicant restart. */
+ return PTR_ERR(req);
}
/* Update out and in/out parameters */
- for (n = 0; n < num_params; n++) {
- struct tee_param *p = supp->param + n;
+ for (n = 0; n < req->num_params; n++) {
+ struct tee_param *p = req->param + n;
- switch (p->attr) {
+ 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].u.value.a;
- p->u.value.b = param[n].u.value.b;
- p->u.value.c = param[n].u.value.c;
+ 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].u.memref.size;
+ p->u.memref.size = param[n + num_meta].u.memref.size;
break;
default:
break;
}
}
- supp->ret = ret;
-
- /* Allow optee_supp_recv() above to do its work */
- supp->supp_next_send = false;
+ req->ret = ret;
/* Let the requesting thread continue */
- complete(&supp->data_from_supp);
-out:
- mutex_unlock(&supp->supp_mutex);
- return rc;
+ complete(&req->c);
+
+ return 0;
}
--
2.7.4
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