linux/drivers/tee/tee_core.c

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/*
* Copyright (c) 2015-2016, Linaro Limited
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/idr.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/tee_drv.h>
#include <linux/uaccess.h>
#include "tee_private.h"
#define TEE_NUM_DEVICES 32
#define TEE_IOCTL_PARAM_SIZE(x) (sizeof(struct tee_param) * (x))
/*
* Unprivileged devices in the lower half range and privileged devices in
* the upper half range.
*/
static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
static DEFINE_SPINLOCK(driver_lock);
static struct class *tee_class;
static dev_t tee_devt;
static int tee_open(struct inode *inode, struct file *filp)
{
int rc;
struct tee_device *teedev;
struct tee_context *ctx;
teedev = container_of(inode->i_cdev, struct tee_device, cdev);
if (!tee_device_get(teedev))
return -EINVAL;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx) {
rc = -ENOMEM;
goto err;
}
ctx->teedev = teedev;
INIT_LIST_HEAD(&ctx->list_shm);
filp->private_data = ctx;
rc = teedev->desc->ops->open(ctx);
if (rc)
goto err;
return 0;
err:
kfree(ctx);
tee_device_put(teedev);
return rc;
}
static int tee_release(struct inode *inode, struct file *filp)
{
struct tee_context *ctx = filp->private_data;
struct tee_device *teedev = ctx->teedev;
struct tee_shm *shm;
ctx->teedev->desc->ops->release(ctx);
mutex_lock(&ctx->teedev->mutex);
list_for_each_entry(shm, &ctx->list_shm, link)
shm->ctx = NULL;
mutex_unlock(&ctx->teedev->mutex);
kfree(ctx);
tee_device_put(teedev);
return 0;
}
static int tee_ioctl_version(struct tee_context *ctx,
struct tee_ioctl_version_data __user *uvers)
{
struct tee_ioctl_version_data vers;
ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
if (copy_to_user(uvers, &vers, sizeof(vers)))
return -EFAULT;
return 0;
}
static int tee_ioctl_shm_alloc(struct tee_context *ctx,
struct tee_ioctl_shm_alloc_data __user *udata)
{
long ret;
struct tee_ioctl_shm_alloc_data data;
struct tee_shm *shm;
if (copy_from_user(&data, udata, sizeof(data)))
return -EFAULT;
/* Currently no input flags are supported */
if (data.flags)
return -EINVAL;
data.id = -1;
shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
if (IS_ERR(shm))
return PTR_ERR(shm);
data.id = shm->id;
data.flags = shm->flags;
data.size = shm->size;
if (copy_to_user(udata, &data, sizeof(data)))
ret = -EFAULT;
else
ret = tee_shm_get_fd(shm);
/*
* When user space closes the file descriptor the shared memory
* should be freed or if tee_shm_get_fd() failed then it will
* be freed immediately.
*/
tee_shm_put(shm);
return ret;
}
static int params_from_user(struct tee_context *ctx, struct tee_param *params,
size_t num_params,
struct tee_ioctl_param __user *uparams)
{
size_t n;
for (n = 0; n < num_params; n++) {
struct tee_shm *shm;
struct tee_ioctl_param ip;
if (copy_from_user(&ip, uparams + n, sizeof(ip)))
return -EFAULT;
/* All unused attribute bits has to be zero */
if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_TYPE_MASK)
return -EINVAL;
params[n].attr = ip.attr;
switch (ip.attr) {
case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
break;
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
params[n].u.value.a = ip.a;
params[n].u.value.b = ip.b;
params[n].u.value.c = ip.c;
break;
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
/*
* If we fail to get a pointer to a shared memory
* object (and increase the ref count) from an
* identifier we return an error. All pointers that
* has been added in params have an increased ref
* count. It's the callers responibility to do
* tee_shm_put() on all resolved pointers.
*/
shm = tee_shm_get_from_id(ctx, ip.c);
if (IS_ERR(shm))
return PTR_ERR(shm);
params[n].u.memref.shm_offs = ip.a;
params[n].u.memref.size = ip.b;
params[n].u.memref.shm = shm;
break;
default:
/* Unknown attribute */
return -EINVAL;
}
}
return 0;
}
static int params_to_user(struct tee_ioctl_param __user *uparams,
size_t num_params, struct tee_param *params)
{
size_t n;
for (n = 0; n < num_params; n++) {
struct tee_ioctl_param __user *up = uparams + n;
struct tee_param *p = params + n;
switch (p->attr) {
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
if (put_user(p->u.value.a, &up->a) ||
put_user(p->u.value.b, &up->b) ||
put_user(p->u.value.c, &up->c))
return -EFAULT;
break;
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
if (put_user((u64)p->u.memref.size, &up->b))
return -EFAULT;
default:
break;
}
}
return 0;
}
static bool param_is_memref(struct tee_param *param)
{
switch (param->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
return true;
default:
return false;
}
}
static int tee_ioctl_open_session(struct tee_context *ctx,
struct tee_ioctl_buf_data __user *ubuf)
{
int rc;
size_t n;
struct tee_ioctl_buf_data buf;
struct tee_ioctl_open_session_arg __user *uarg;
struct tee_ioctl_open_session_arg arg;
struct tee_ioctl_param __user *uparams = NULL;
struct tee_param *params = NULL;
bool have_session = false;
if (!ctx->teedev->desc->ops->open_session)
return -EINVAL;
if (copy_from_user(&buf, ubuf, sizeof(buf)))
return -EFAULT;
if (buf.buf_len > TEE_MAX_ARG_SIZE ||
buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
return -EINVAL;
uarg = u64_to_user_ptr(buf.buf_ptr);
if (copy_from_user(&arg, uarg, sizeof(arg)))
return -EFAULT;
if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
return -EINVAL;
if (arg.num_params) {
params = kcalloc(arg.num_params, sizeof(struct tee_param),
GFP_KERNEL);
if (!params)
return -ENOMEM;
uparams = uarg->params;
rc = params_from_user(ctx, params, arg.num_params, uparams);
if (rc)
goto out;
}
rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
if (rc)
goto out;
have_session = true;
if (put_user(arg.session, &uarg->session) ||
put_user(arg.ret, &uarg->ret) ||
put_user(arg.ret_origin, &uarg->ret_origin)) {
rc = -EFAULT;
goto out;
}
rc = params_to_user(uparams, arg.num_params, params);
out:
/*
* If we've succeeded to open the session but failed to communicate
* it back to user space, close the session again to avoid leakage.
*/
if (rc && have_session && ctx->teedev->desc->ops->close_session)
ctx->teedev->desc->ops->close_session(ctx, arg.session);
if (params) {
/* Decrease ref count for all valid shared memory pointers */
for (n = 0; n < arg.num_params; n++)
if (param_is_memref(params + n) &&
params[n].u.memref.shm)
tee_shm_put(params[n].u.memref.shm);
kfree(params);
}
return rc;
}
static int tee_ioctl_invoke(struct tee_context *ctx,
struct tee_ioctl_buf_data __user *ubuf)
{
int rc;
size_t n;
struct tee_ioctl_buf_data buf;
struct tee_ioctl_invoke_arg __user *uarg;
struct tee_ioctl_invoke_arg arg;
struct tee_ioctl_param __user *uparams = NULL;
struct tee_param *params = NULL;
if (!ctx->teedev->desc->ops->invoke_func)
return -EINVAL;
if (copy_from_user(&buf, ubuf, sizeof(buf)))
return -EFAULT;
if (buf.buf_len > TEE_MAX_ARG_SIZE ||
buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
return -EINVAL;
uarg = u64_to_user_ptr(buf.buf_ptr);
if (copy_from_user(&arg, uarg, sizeof(arg)))
return -EFAULT;
if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
return -EINVAL;
if (arg.num_params) {
params = kcalloc(arg.num_params, sizeof(struct tee_param),
GFP_KERNEL);
if (!params)
return -ENOMEM;
uparams = uarg->params;
rc = params_from_user(ctx, params, arg.num_params, uparams);
if (rc)
goto out;
}
rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
if (rc)
goto out;
if (put_user(arg.ret, &uarg->ret) ||
put_user(arg.ret_origin, &uarg->ret_origin)) {
rc = -EFAULT;
goto out;
}
rc = params_to_user(uparams, arg.num_params, params);
out:
if (params) {
/* Decrease ref count for all valid shared memory pointers */
for (n = 0; n < arg.num_params; n++)
if (param_is_memref(params + n) &&
params[n].u.memref.shm)
tee_shm_put(params[n].u.memref.shm);
kfree(params);
}
return rc;
}
static int tee_ioctl_cancel(struct tee_context *ctx,
struct tee_ioctl_cancel_arg __user *uarg)
{
struct tee_ioctl_cancel_arg arg;
if (!ctx->teedev->desc->ops->cancel_req)
return -EINVAL;
if (copy_from_user(&arg, uarg, sizeof(arg)))
return -EFAULT;
return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
arg.session);
}
static int
tee_ioctl_close_session(struct tee_context *ctx,
struct tee_ioctl_close_session_arg __user *uarg)
{
struct tee_ioctl_close_session_arg arg;
if (!ctx->teedev->desc->ops->close_session)
return -EINVAL;
if (copy_from_user(&arg, uarg, sizeof(arg)))
return -EFAULT;
return ctx->teedev->desc->ops->close_session(ctx, arg.session);
}
static int params_to_supp(struct tee_context *ctx,
struct tee_ioctl_param __user *uparams,
size_t num_params, struct tee_param *params)
{
size_t n;
for (n = 0; n < num_params; n++) {
struct tee_ioctl_param ip;
struct tee_param *p = params + n;
ip.attr = p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK;
switch (p->attr) {
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
ip.a = p->u.value.a;
ip.b = p->u.value.b;
ip.c = p->u.value.c;
break;
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
ip.b = p->u.memref.size;
if (!p->u.memref.shm) {
ip.a = 0;
ip.c = (u64)-1; /* invalid shm id */
break;
}
ip.a = p->u.memref.shm_offs;
ip.c = p->u.memref.shm->id;
break;
default:
ip.a = 0;
ip.b = 0;
ip.c = 0;
break;
}
if (copy_to_user(uparams + n, &ip, sizeof(ip)))
return -EFAULT;
}
return 0;
}
static int tee_ioctl_supp_recv(struct tee_context *ctx,
struct tee_ioctl_buf_data __user *ubuf)
{
int rc;
struct tee_ioctl_buf_data buf;
struct tee_iocl_supp_recv_arg __user *uarg;
struct tee_param *params;
u32 num_params;
u32 func;
if (!ctx->teedev->desc->ops->supp_recv)
return -EINVAL;
if (copy_from_user(&buf, ubuf, sizeof(buf)))
return -EFAULT;
if (buf.buf_len > TEE_MAX_ARG_SIZE ||
buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
return -EINVAL;
uarg = u64_to_user_ptr(buf.buf_ptr);
if (get_user(num_params, &uarg->num_params))
return -EFAULT;
if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
return -EINVAL;
params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
if (!params)
return -ENOMEM;
rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
if (rc)
goto out;
if (put_user(func, &uarg->func) ||
put_user(num_params, &uarg->num_params)) {
rc = -EFAULT;
goto out;
}
rc = params_to_supp(ctx, uarg->params, num_params, params);
out:
kfree(params);
return rc;
}
static int params_from_supp(struct tee_param *params, size_t num_params,
struct tee_ioctl_param __user *uparams)
{
size_t n;
for (n = 0; n < num_params; n++) {
struct tee_param *p = params + n;
struct tee_ioctl_param ip;
if (copy_from_user(&ip, uparams + n, sizeof(ip)))
return -EFAULT;
/* All unused attribute bits has to be zero */
if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_TYPE_MASK)
return -EINVAL;
p->attr = ip.attr;
switch (ip.attr) {
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
/* Only out and in/out values can be updated */
p->u.value.a = ip.a;
p->u.value.b = ip.b;
p->u.value.c = ip.c;
break;
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
/*
* Only the size of the memref can be updated.
* Since we don't have access to the original
* parameters here, only store the supplied size.
* The driver will copy the updated size into the
* original parameters.
*/
p->u.memref.shm = NULL;
p->u.memref.shm_offs = 0;
p->u.memref.size = ip.b;
break;
default:
memset(&p->u, 0, sizeof(p->u));
break;
}
}
return 0;
}
static int tee_ioctl_supp_send(struct tee_context *ctx,
struct tee_ioctl_buf_data __user *ubuf)
{
long rc;
struct tee_ioctl_buf_data buf;
struct tee_iocl_supp_send_arg __user *uarg;
struct tee_param *params;
u32 num_params;
u32 ret;
/* Not valid for this driver */
if (!ctx->teedev->desc->ops->supp_send)
return -EINVAL;
if (copy_from_user(&buf, ubuf, sizeof(buf)))
return -EFAULT;
if (buf.buf_len > TEE_MAX_ARG_SIZE ||
buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
return -EINVAL;
uarg = u64_to_user_ptr(buf.buf_ptr);
if (get_user(ret, &uarg->ret) ||
get_user(num_params, &uarg->num_params))
return -EFAULT;
if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
return -EINVAL;
params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
if (!params)
return -ENOMEM;
rc = params_from_supp(params, num_params, uarg->params);
if (rc)
goto out;
rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
out:
kfree(params);
return rc;
}
static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct tee_context *ctx = filp->private_data;
void __user *uarg = (void __user *)arg;
switch (cmd) {
case TEE_IOC_VERSION:
return tee_ioctl_version(ctx, uarg);
case TEE_IOC_SHM_ALLOC:
return tee_ioctl_shm_alloc(ctx, uarg);
case TEE_IOC_OPEN_SESSION:
return tee_ioctl_open_session(ctx, uarg);
case TEE_IOC_INVOKE:
return tee_ioctl_invoke(ctx, uarg);
case TEE_IOC_CANCEL:
return tee_ioctl_cancel(ctx, uarg);
case TEE_IOC_CLOSE_SESSION:
return tee_ioctl_close_session(ctx, uarg);
case TEE_IOC_SUPPL_RECV:
return tee_ioctl_supp_recv(ctx, uarg);
case TEE_IOC_SUPPL_SEND:
return tee_ioctl_supp_send(ctx, uarg);
default:
return -EINVAL;
}
}
static const struct file_operations tee_fops = {
.owner = THIS_MODULE,
.open = tee_open,
.release = tee_release,
.unlocked_ioctl = tee_ioctl,
.compat_ioctl = tee_ioctl,
};
static void tee_release_device(struct device *dev)
{
struct tee_device *teedev = container_of(dev, struct tee_device, dev);
spin_lock(&driver_lock);
clear_bit(teedev->id, dev_mask);
spin_unlock(&driver_lock);
mutex_destroy(&teedev->mutex);
idr_destroy(&teedev->idr);
kfree(teedev);
}
/**
* tee_device_alloc() - Allocate a new struct tee_device instance
* @teedesc: Descriptor for this driver
* @dev: Parent device for this device
* @pool: Shared memory pool, NULL if not used
* @driver_data: Private driver data for this device
*
* Allocates a new struct tee_device instance. The device is
* removed by tee_device_unregister().
*
* @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
*/
struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
struct device *dev,
struct tee_shm_pool *pool,
void *driver_data)
{
struct tee_device *teedev;
void *ret;
int rc;
int offs = 0;
if (!teedesc || !teedesc->name || !teedesc->ops ||
!teedesc->ops->get_version || !teedesc->ops->open ||
!teedesc->ops->release || !pool)
return ERR_PTR(-EINVAL);
teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
if (!teedev) {
ret = ERR_PTR(-ENOMEM);
goto err;
}
if (teedesc->flags & TEE_DESC_PRIVILEGED)
offs = TEE_NUM_DEVICES / 2;
spin_lock(&driver_lock);
teedev->id = find_next_zero_bit(dev_mask, TEE_NUM_DEVICES, offs);
if (teedev->id < TEE_NUM_DEVICES)
set_bit(teedev->id, dev_mask);
spin_unlock(&driver_lock);
if (teedev->id >= TEE_NUM_DEVICES) {
ret = ERR_PTR(-ENOMEM);
goto err;
}
snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
teedev->id - offs);
teedev->dev.class = tee_class;
teedev->dev.release = tee_release_device;
teedev->dev.parent = dev;
teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
rc = dev_set_name(&teedev->dev, "%s", teedev->name);
if (rc) {
ret = ERR_PTR(rc);
goto err_devt;
}
cdev_init(&teedev->cdev, &tee_fops);
teedev->cdev.owner = teedesc->owner;
teedev->cdev.kobj.parent = &teedev->dev.kobj;
dev_set_drvdata(&teedev->dev, driver_data);
device_initialize(&teedev->dev);
/* 1 as tee_device_unregister() does one final tee_device_put() */
teedev->num_users = 1;
init_completion(&teedev->c_no_users);
mutex_init(&teedev->mutex);
idr_init(&teedev->idr);
teedev->desc = teedesc;
teedev->pool = pool;
return teedev;
err_devt:
unregister_chrdev_region(teedev->dev.devt, 1);
err:
pr_err("could not register %s driver\n",
teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
if (teedev && teedev->id < TEE_NUM_DEVICES) {
spin_lock(&driver_lock);
clear_bit(teedev->id, dev_mask);
spin_unlock(&driver_lock);
}
kfree(teedev);
return ret;
}
EXPORT_SYMBOL_GPL(tee_device_alloc);
static ssize_t implementation_id_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tee_device *teedev = container_of(dev, struct tee_device, dev);
struct tee_ioctl_version_data vers;
teedev->desc->ops->get_version(teedev, &vers);
return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
}
static DEVICE_ATTR_RO(implementation_id);
static struct attribute *tee_dev_attrs[] = {
&dev_attr_implementation_id.attr,
NULL
};
static const struct attribute_group tee_dev_group = {
.attrs = tee_dev_attrs,
};
/**
* tee_device_register() - Registers a TEE device
* @teedev: Device to register
*
* tee_device_unregister() need to be called to remove the @teedev if
* this function fails.
*
* @returns < 0 on failure
*/
int tee_device_register(struct tee_device *teedev)
{
int rc;
if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
dev_err(&teedev->dev, "attempt to register twice\n");
return -EINVAL;
}
rc = cdev_add(&teedev->cdev, teedev->dev.devt, 1);
if (rc) {
dev_err(&teedev->dev,
"unable to cdev_add() %s, major %d, minor %d, err=%d\n",
teedev->name, MAJOR(teedev->dev.devt),
MINOR(teedev->dev.devt), rc);
return rc;
}
rc = device_add(&teedev->dev);
if (rc) {
dev_err(&teedev->dev,
"unable to device_add() %s, major %d, minor %d, err=%d\n",
teedev->name, MAJOR(teedev->dev.devt),
MINOR(teedev->dev.devt), rc);
goto err_device_add;
}
rc = sysfs_create_group(&teedev->dev.kobj, &tee_dev_group);
if (rc) {
dev_err(&teedev->dev,
"failed to create sysfs attributes, err=%d\n", rc);
goto err_sysfs_create_group;
}
teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
return 0;
err_sysfs_create_group:
device_del(&teedev->dev);
err_device_add:
cdev_del(&teedev->cdev);
return rc;
}
EXPORT_SYMBOL_GPL(tee_device_register);
void tee_device_put(struct tee_device *teedev)
{
mutex_lock(&teedev->mutex);
/* Shouldn't put in this state */
if (!WARN_ON(!teedev->desc)) {
teedev->num_users--;
if (!teedev->num_users) {
teedev->desc = NULL;
complete(&teedev->c_no_users);
}
}
mutex_unlock(&teedev->mutex);
}
bool tee_device_get(struct tee_device *teedev)
{
mutex_lock(&teedev->mutex);
if (!teedev->desc) {
mutex_unlock(&teedev->mutex);
return false;
}
teedev->num_users++;
mutex_unlock(&teedev->mutex);
return true;
}
/**
* tee_device_unregister() - Removes a TEE device
* @teedev: Device to unregister
*
* This function should be called to remove the @teedev even if
* tee_device_register() hasn't been called yet. Does nothing if
* @teedev is NULL.
*/
void tee_device_unregister(struct tee_device *teedev)
{
if (!teedev)
return;
if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
sysfs_remove_group(&teedev->dev.kobj, &tee_dev_group);
cdev_del(&teedev->cdev);
device_del(&teedev->dev);
}
tee_device_put(teedev);
wait_for_completion(&teedev->c_no_users);
/*
* No need to take a mutex any longer now since teedev->desc was
* set to NULL before teedev->c_no_users was completed.
*/
teedev->pool = NULL;
put_device(&teedev->dev);
}
EXPORT_SYMBOL_GPL(tee_device_unregister);
/**
* tee_get_drvdata() - Return driver_data pointer
* @teedev: Device containing the driver_data pointer
* @returns the driver_data pointer supplied to tee_register().
*/
void *tee_get_drvdata(struct tee_device *teedev)
{
return dev_get_drvdata(&teedev->dev);
}
EXPORT_SYMBOL_GPL(tee_get_drvdata);
static int __init tee_init(void)
{
int rc;
tee_class = class_create(THIS_MODULE, "tee");
if (IS_ERR(tee_class)) {
pr_err("couldn't create class\n");
return PTR_ERR(tee_class);
}
rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
if (rc) {
pr_err("failed to allocate char dev region\n");
class_destroy(tee_class);
tee_class = NULL;
}
return rc;
}
static void __exit tee_exit(void)
{
class_destroy(tee_class);
tee_class = NULL;
unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
}
subsys_initcall(tee_init);
module_exit(tee_exit);
MODULE_AUTHOR("Linaro");
MODULE_DESCRIPTION("TEE Driver");
MODULE_VERSION("1.0");
MODULE_LICENSE("GPL v2");