1 files changed, 526 insertions, 0 deletions
diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
new file mode 100644
index 000000000..290b1bb0e
--- /dev/null
+++ b/drivers/tee/optee/call.c
@@ -0,0 +1,526 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2015-2021, Linaro Limited
+ */
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/types.h>
+#include "optee_private.h"
+
+#define MAX_ARG_PARAM_COUNT	6
+
+/*
+ * How much memory we allocate for each entry. This doesn't have to be a
+ * single page, but it makes sense to keep at least keep it as multiples of
+ * the page size.
+ */
+#define SHM_ENTRY_SIZE		PAGE_SIZE
+
+/*
+ * We need to have a compile time constant to be able to determine the
+ * maximum needed size of the bit field.
+ */
+#define MIN_ARG_SIZE		OPTEE_MSG_GET_ARG_SIZE(MAX_ARG_PARAM_COUNT)
+#define MAX_ARG_COUNT_PER_ENTRY	(SHM_ENTRY_SIZE / MIN_ARG_SIZE)
+
+/*
+ * Shared memory for argument structs are cached here. The number of
+ * arguments structs that can fit is determined at runtime depending on the
+ * needed RPC parameter count reported by secure world
+ * (optee->rpc_param_count).
+ */
+struct optee_shm_arg_entry {
+	struct list_head list_node;
+	struct tee_shm *shm;
+	DECLARE_BITMAP(map, MAX_ARG_COUNT_PER_ENTRY);
+};
+
+void optee_cq_wait_init(struct optee_call_queue *cq,
+			struct optee_call_waiter *w)
+{
+	/*
+	 * We're preparing to make a call to secure world. In case we can't
+	 * allocate a thread in secure world we'll end up waiting in
+	 * optee_cq_wait_for_completion().
+	 *
+	 * Normally if there's no contention in secure world the call will
+	 * complete and we can cleanup directly with optee_cq_wait_final().
+	 */
+	mutex_lock(&cq->mutex);
+
+	/*
+	 * We add ourselves to the queue, but we don't wait. This
+	 * guarantees that we don't lose a completion if secure world
+	 * returns busy and another thread just exited and try to complete
+	 * someone.
+	 */
+	init_completion(&w->c);
+	list_add_tail(&w->list_node, &cq->waiters);
+
+	mutex_unlock(&cq->mutex);
+}
+
+void optee_cq_wait_for_completion(struct optee_call_queue *cq,
+				  struct optee_call_waiter *w)
+{
+	wait_for_completion(&w->c);
+
+	mutex_lock(&cq->mutex);
+
+	/* Move to end of list to get out of the way for other waiters */
+	list_del(&w->list_node);
+	reinit_completion(&w->c);
+	list_add_tail(&w->list_node, &cq->waiters);
+
+	mutex_unlock(&cq->mutex);
+}
+
+static void optee_cq_complete_one(struct optee_call_queue *cq)
+{
+	struct optee_call_waiter *w;
+
+	list_for_each_entry(w, &cq->waiters, list_node) {
+		if (!completion_done(&w->c)) {
+			complete(&w->c);
+			break;
+		}
+	}
+}
+
+void optee_cq_wait_final(struct optee_call_queue *cq,
+			 struct optee_call_waiter *w)
+{
+	/*
+	 * We're done with the call to secure world. The thread in secure
+	 * world that was used for this call is now available for some
+	 * other task to use.
+	 */
+	mutex_lock(&cq->mutex);
+
+	/* Get out of the list */
+	list_del(&w->list_node);
+
+	/* Wake up one eventual waiting task */
+	optee_cq_complete_one(cq);
+
+	/*
+	 * If we're completed we've got a completion from another task that
+	 * was just done with its call to secure world. Since yet another
+	 * thread now is available in secure world wake up another eventual
+	 * waiting task.
+	 */
+	if (completion_done(&w->c))
+		optee_cq_complete_one(cq);
+
+	mutex_unlock(&cq->mutex);
+}
+
+/* Requires the filpstate mutex to be held */
+static struct optee_session *find_session(struct optee_context_data *ctxdata,
+					  u32 session_id)
+{
+	struct optee_session *sess;
+
+	list_for_each_entry(sess, &ctxdata->sess_list, list_node)
+		if (sess->session_id == session_id)
+			return sess;
+
+	return NULL;
+}
+
+void optee_shm_arg_cache_init(struct optee *optee, u32 flags)
+{
+	INIT_LIST_HEAD(&optee->shm_arg_cache.shm_args);
+	mutex_init(&optee->shm_arg_cache.mutex);
+	optee->shm_arg_cache.flags = flags;
+}
+
+void optee_shm_arg_cache_uninit(struct optee *optee)
+{
+	struct list_head *head = &optee->shm_arg_cache.shm_args;
+	struct optee_shm_arg_entry *entry;
+
+	mutex_destroy(&optee->shm_arg_cache.mutex);
+	while (!list_empty(head)) {
+		entry = list_first_entry(head, struct optee_shm_arg_entry,
+					 list_node);
+		list_del(&entry->list_node);
+		if (find_first_bit(entry->map, MAX_ARG_COUNT_PER_ENTRY) !=
+		     MAX_ARG_COUNT_PER_ENTRY) {
+			pr_err("Freeing non-free entry\n");
+		}
+		tee_shm_free(entry->shm);
+		kfree(entry);
+	}
+}
+
+size_t optee_msg_arg_size(size_t rpc_param_count)
+{
+	size_t sz = OPTEE_MSG_GET_ARG_SIZE(MAX_ARG_PARAM_COUNT);
+
+	if (rpc_param_count)
+		sz += OPTEE_MSG_GET_ARG_SIZE(rpc_param_count);
+
+	return sz;
+}
+
+/**
+ * optee_get_msg_arg() - Provide shared memory for argument struct
+ * @ctx:	Caller TEE context
+ * @num_params:	Number of parameter to store
+ * @entry_ret:	Entry pointer, needed when freeing the buffer
+ * @shm_ret:	Shared memory buffer
+ * @offs_ret:	Offset of argument strut in shared memory buffer
+ *
+ * @returns a pointer to the argument struct in memory, else an ERR_PTR
+ */
+struct optee_msg_arg *optee_get_msg_arg(struct tee_context *ctx,
+					size_t num_params,
+					struct optee_shm_arg_entry **entry_ret,
+					struct tee_shm **shm_ret,
+					u_int *offs_ret)
+{
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
+	size_t sz = optee_msg_arg_size(optee->rpc_param_count);
+	struct optee_shm_arg_entry *entry;
+	struct optee_msg_arg *ma;
+	size_t args_per_entry;
+	u_long bit;
+	u_int offs;
+	void *res;
+
+	if (num_params > MAX_ARG_PARAM_COUNT)
+		return ERR_PTR(-EINVAL);
+
+	if (optee->shm_arg_cache.flags & OPTEE_SHM_ARG_SHARED)
+		args_per_entry = SHM_ENTRY_SIZE / sz;
+	else
+		args_per_entry = 1;
+
+	mutex_lock(&optee->shm_arg_cache.mutex);
+	list_for_each_entry(entry, &optee->shm_arg_cache.shm_args, list_node) {
+		bit = find_first_zero_bit(entry->map, MAX_ARG_COUNT_PER_ENTRY);
+		if (bit < args_per_entry)
+			goto have_entry;
+	}
+
+	/*
+	 * No entry was found, let's allocate a new.
+	 */
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry) {
+		res = ERR_PTR(-ENOMEM);
+		goto out;
+	}
+
+	if (optee->shm_arg_cache.flags & OPTEE_SHM_ARG_ALLOC_PRIV)
+		res = tee_shm_alloc_priv_buf(ctx, SHM_ENTRY_SIZE);
+	else
+		res = tee_shm_alloc_kernel_buf(ctx, SHM_ENTRY_SIZE);
+
+	if (IS_ERR(res)) {
+		kfree(entry);
+		goto out;
+	}
+	entry->shm = res;
+	list_add(&entry->list_node, &optee->shm_arg_cache.shm_args);
+	bit = 0;
+
+have_entry:
+	offs = bit * sz;
+	res = tee_shm_get_va(entry->shm, offs);
+	if (IS_ERR(res))
+		goto out;
+	ma = res;
+	set_bit(bit, entry->map);
+	memset(ma, 0, sz);
+	ma->num_params = num_params;
+	*entry_ret = entry;
+	*shm_ret = entry->shm;
+	*offs_ret = offs;
+out:
+	mutex_unlock(&optee->shm_arg_cache.mutex);
+	return res;
+}
+
+/**
+ * optee_free_msg_arg() - Free previsouly obtained shared memory
+ * @ctx:	Caller TEE context
+ * @entry:	Pointer returned when the shared memory was obtained
+ * @offs:	Offset of shared memory buffer to free
+ *
+ * This function frees the shared memory obtained with optee_get_msg_arg().
+ */
+void optee_free_msg_arg(struct tee_context *ctx,
+			struct optee_shm_arg_entry *entry, u_int offs)
+{
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
+	size_t sz = optee_msg_arg_size(optee->rpc_param_count);
+	u_long bit;
+
+	if (offs > SHM_ENTRY_SIZE || offs % sz) {
+		pr_err("Invalid offs %u\n", offs);
+		return;
+	}
+	bit = offs / sz;
+
+	mutex_lock(&optee->shm_arg_cache.mutex);
+
+	if (!test_bit(bit, entry->map))
+		pr_err("Bit pos %lu is already free\n", bit);
+	clear_bit(bit, entry->map);
+
+	mutex_unlock(&optee->shm_arg_cache.mutex);
+}
+
+int optee_open_session(struct tee_context *ctx,
+		       struct tee_ioctl_open_session_arg *arg,
+		       struct tee_param *param)
+{
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
+	struct optee_context_data *ctxdata = ctx->data;
+	struct optee_shm_arg_entry *entry;
+	struct tee_shm *shm;
+	struct optee_msg_arg *msg_arg;
+	struct optee_session *sess = NULL;
+	uuid_t client_uuid;
+	u_int offs;
+	int rc;
+
+	/* +2 for the meta parameters added below */
+	msg_arg = optee_get_msg_arg(ctx, arg->num_params + 2,
+				    &entry, &shm, &offs);
+	if (IS_ERR(msg_arg))
+		return PTR_ERR(msg_arg);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_OPEN_SESSION;
+	msg_arg->cancel_id = arg->cancel_id;
+
+	/*
+	 * Initialize and add the meta parameters needed when opening a
+	 * session.
+	 */
+	msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT |
+				  OPTEE_MSG_ATTR_META;
+	msg_arg->params[1].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT |
+				  OPTEE_MSG_ATTR_META;
+	memcpy(&msg_arg->params[0].u.value, arg->uuid, sizeof(arg->uuid));
+	msg_arg->params[1].u.value.c = arg->clnt_login;
+
+	rc = tee_session_calc_client_uuid(&client_uuid, arg->clnt_login,
+					  arg->clnt_uuid);
+	if (rc)
+		goto out;
+	export_uuid(msg_arg->params[1].u.octets, &client_uuid);
+
+	rc = optee->ops->to_msg_param(optee, msg_arg->params + 2,
+				      arg->num_params, param);
+	if (rc)
+		goto out;
+
+	sess = kzalloc(sizeof(*sess), GFP_KERNEL);
+	if (!sess) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	if (optee->ops->do_call_with_arg(ctx, shm, offs)) {
+		msg_arg->ret = TEEC_ERROR_COMMUNICATION;
+		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
+	}
+
+	if (msg_arg->ret == TEEC_SUCCESS) {
+		/* A new session has been created, add it to the list. */
+		sess->session_id = msg_arg->session;
+		mutex_lock(&ctxdata->mutex);
+		list_add(&sess->list_node, &ctxdata->sess_list);
+		mutex_unlock(&ctxdata->mutex);
+	} else {
+		kfree(sess);
+	}
+
+	if (optee->ops->from_msg_param(optee, param, arg->num_params,
+				       msg_arg->params + 2)) {
+		arg->ret = TEEC_ERROR_COMMUNICATION;
+		arg->ret_origin = TEEC_ORIGIN_COMMS;
+		/* Close session again to avoid leakage */
+		optee_close_session(ctx, msg_arg->session);
+	} else {
+		arg->session = msg_arg->session;
+		arg->ret = msg_arg->ret;
+		arg->ret_origin = msg_arg->ret_origin;
+	}
+out:
+	optee_free_msg_arg(ctx, entry, offs);
+
+	return rc;
+}
+
+int optee_close_session_helper(struct tee_context *ctx, u32 session)
+{
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
+	struct optee_shm_arg_entry *entry;
+	struct optee_msg_arg *msg_arg;
+	struct tee_shm *shm;
+	u_int offs;
+
+	msg_arg = optee_get_msg_arg(ctx, 0, &entry, &shm, &offs);
+	if (IS_ERR(msg_arg))
+		return PTR_ERR(msg_arg);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;
+	msg_arg->session = session;
+	optee->ops->do_call_with_arg(ctx, shm, offs);
+
+	optee_free_msg_arg(ctx, entry, offs);
+
+	return 0;
+}
+
+int optee_close_session(struct tee_context *ctx, u32 session)
+{
+	struct optee_context_data *ctxdata = ctx->data;
+	struct optee_session *sess;
+
+	/* Check that the session is valid and remove it from the list */
+	mutex_lock(&ctxdata->mutex);
+	sess = find_session(ctxdata, session);
+	if (sess)
+		list_del(&sess->list_node);
+	mutex_unlock(&ctxdata->mutex);
+	if (!sess)
+		return -EINVAL;
+	kfree(sess);
+
+	return optee_close_session_helper(ctx, session);
+}
+
+int optee_invoke_func(struct tee_context *ctx, struct tee_ioctl_invoke_arg *arg,
+		      struct tee_param *param)
+{
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
+	struct optee_context_data *ctxdata = ctx->data;
+	struct optee_shm_arg_entry *entry;
+	struct optee_msg_arg *msg_arg;
+	struct optee_session *sess;
+	struct tee_shm *shm;
+	u_int offs;
+	int rc;
+
+	/* Check that the session is valid */
+	mutex_lock(&ctxdata->mutex);
+	sess = find_session(ctxdata, arg->session);
+	mutex_unlock(&ctxdata->mutex);
+	if (!sess)
+		return -EINVAL;
+
+	msg_arg = optee_get_msg_arg(ctx, arg->num_params,
+				    &entry, &shm, &offs);
+	if (IS_ERR(msg_arg))
+		return PTR_ERR(msg_arg);
+	msg_arg->cmd = OPTEE_MSG_CMD_INVOKE_COMMAND;
+	msg_arg->func = arg->func;
+	msg_arg->session = arg->session;
+	msg_arg->cancel_id = arg->cancel_id;
+
+	rc = optee->ops->to_msg_param(optee, msg_arg->params, arg->num_params,
+				      param);
+	if (rc)
+		goto out;
+
+	if (optee->ops->do_call_with_arg(ctx, shm, offs)) {
+		msg_arg->ret = TEEC_ERROR_COMMUNICATION;
+		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
+	}
+
+	if (optee->ops->from_msg_param(optee, param, arg->num_params,
+				       msg_arg->params)) {
+		msg_arg->ret = TEEC_ERROR_COMMUNICATION;
+		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
+	}
+
+	arg->ret = msg_arg->ret;
+	arg->ret_origin = msg_arg->ret_origin;
+out:
+	optee_free_msg_arg(ctx, entry, offs);
+	return rc;
+}
+
+int optee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
+{
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
+	struct optee_context_data *ctxdata = ctx->data;
+	struct optee_shm_arg_entry *entry;
+	struct optee_msg_arg *msg_arg;
+	struct optee_session *sess;
+	struct tee_shm *shm;
+	u_int offs;
+
+	/* Check that the session is valid */
+	mutex_lock(&ctxdata->mutex);
+	sess = find_session(ctxdata, session);
+	mutex_unlock(&ctxdata->mutex);
+	if (!sess)
+		return -EINVAL;
+
+	msg_arg = optee_get_msg_arg(ctx, 0, &entry, &shm, &offs);
+	if (IS_ERR(msg_arg))
+		return PTR_ERR(msg_arg);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_CANCEL;
+	msg_arg->session = session;
+	msg_arg->cancel_id = cancel_id;
+	optee->ops->do_call_with_arg(ctx, shm, offs);
+
+	optee_free_msg_arg(ctx, entry, offs);
+	return 0;
+}
+
+static bool is_normal_memory(pgprot_t p)
+{
+#if defined(CONFIG_ARM)
+	return (((pgprot_val(p) & L_PTE_MT_MASK) == L_PTE_MT_WRITEALLOC) ||
+		((pgprot_val(p) & L_PTE_MT_MASK) == L_PTE_MT_WRITEBACK));
+#elif defined(CONFIG_ARM64)
+	return (pgprot_val(p) & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL);
+#else
+#error "Unuspported architecture"
+#endif
+}
+
+static int __check_mem_type(struct mm_struct *mm, unsigned long start,
+				unsigned long end)
+{
+	struct vm_area_struct *vma;
+	VMA_ITERATOR(vmi, mm, start);
+
+	for_each_vma_range(vmi, vma, end) {
+		if (!is_normal_memory(vma->vm_page_prot))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+int optee_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((void *)start) || is_vmalloc_addr((void *)start))
+		return 0;
+
+	mmap_read_lock(mm);
+	rc = __check_mem_type(mm, start, start + num_pages * PAGE_SIZE);
+	mmap_read_unlock(mm);
+
+	return rc;
+}