// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2015-2021, 2023 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_core.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_init(struct optee_call_queue *cq, int thread_count)
{
mutex_init(&cq->mutex);
INIT_LIST_HEAD(&cq->waiters);
/*
* If cq->total_thread_count is 0 then we're not trying to keep
* track of how many free threads we have, instead we're relying on
* the secure world to tell us when we're out of thread and have to
* wait for another thread to become available.
*/
cq->total_thread_count = thread_count;
cq->free_thread_count = thread_count;
}
void optee_cq_wait_init(struct optee_call_queue *cq,
struct optee_call_waiter *w, bool sys_thread)
{
unsigned int free_thread_threshold;
bool need_wait = false;
memset(w, 0, sizeof(*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);
w->sys_thread = sys_thread;
if (cq->total_thread_count) {
if (sys_thread || !cq->sys_thread_req_count)
free_thread_threshold = 0;
else
free_thread_threshold = 1;
if (cq->free_thread_count > free_thread_threshold)
cq->free_thread_count--;
else
need_wait = true;
}
mutex_unlock(&cq->mutex);
while (need_wait) {
optee_cq_wait_for_completion(cq, w);
mutex_lock(&cq->mutex);
if (sys_thread || !cq->sys_thread_req_count)
free_thread_threshold = 0;
else
free_thread_threshold = 1;
if (cq->free_thread_count > free_thread_threshold) {
cq->free_thread_count--;
need_wait = false;
}
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;
/* Wake a waiting system session if any, prior to a normal session */
list_for_each_entry(w, &cq->waiters, list_node) {
if (w->sys_thread && !completion_done(&w->c)) {
complete(&w->c);
return;
}
}
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);
cq->free_thread_count++;
/* 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);
}
/* Count registered system sessions to reserved a system thread or not */
static bool optee_cq_incr_sys_thread_count(struct optee_call_queue *cq)
{
if (cq->total_thread_count <= 1)
return false;
mutex_lock(&cq->mutex);
cq->sys_thread_req_count++;
mutex_unlock(&cq->mutex);
return true;
}
static void optee_cq_decr_sys_thread_count(struct optee_call_queue *cq)
{
mutex_lock(&cq->mutex);
cq->sys_thread_req_count--;
/* If there's someone waiting, let it resume */
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,
sess->use_sys_thread)) {
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_system_session(struct tee_context *ctx, u32 session)
{
struct optee *optee = tee_get_drvdata(ctx->teedev);
struct optee_context_data *ctxdata = ctx->data;
struct optee_session *sess;
int rc = -EINVAL;
mutex_lock(&ctxdata->mutex);
sess = find_session(ctxdata, session);
if (sess && (sess->use_sys_thread ||
optee_cq_incr_sys_thread_count(&optee->call_queue))) {
sess->use_sys_thread = true;
rc = 0;
}
mutex_unlock(&ctxdata->mutex);
return rc;
}
int optee_close_session_helper(struct tee_context *ctx, u32 session,
bool system_thread)
{
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, system_thread);
optee_free_msg_arg(ctx, entry, offs);
if (system_thread)
optee_cq_decr_sys_thread_count(&optee->call_queue);
return 0;
}
int optee_close_session(struct tee_context *ctx, u32 session)
{
struct optee_context_data *ctxdata = ctx->data;
struct optee_session *sess;
bool system_thread;
/* 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;
system_thread = sess->use_sys_thread;
kfree(sess);
return optee_close_session_helper(ctx, session, system_thread);
}
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;
bool system_thread;
u_int offs;
int rc;
/* Check that the session is valid */
mutex_lock(&ctxdata->mutex);
sess = find_session(ctxdata, arg->session);
if (sess)
system_thread = sess->use_sys_thread;
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, system_thread)) {
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;
bool system_thread;
struct tee_shm *shm;
u_int offs;
/* Check that the session is valid */
mutex_lock(&ctxdata->mutex);
sess = find_session(ctxdata, session);
if (sess)
system_thread = sess->use_sys_thread;
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, system_thread);
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 "Unsupported 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;
}
static int simple_call_with_arg(struct tee_context *ctx, u32 cmd)
{
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 = cmd;
optee->ops->do_call_with_arg(ctx, shm, offs, false);
optee_free_msg_arg(ctx, entry, offs);
return 0;
}
int optee_do_bottom_half(struct tee_context *ctx)
{
return simple_call_with_arg(ctx, OPTEE_MSG_CMD_DO_BOTTOM_HALF);
}
int optee_stop_async_notif(struct tee_context *ctx)
{
return simple_call_with_arg(ctx, OPTEE_MSG_CMD_STOP_ASYNC_NOTIF);
}
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