BACKPORT: tee: generic TEE subsystem
Initial patch for generic TEE subsystem.
This subsystem provides:
* Registration/un-registration of TEE drivers.
* Shared memory between normal world and secure world.
* Ioctl interface for interaction with user space.
* Sysfs implementation_id of TEE driver
A TEE (Trusted Execution Environment) driver is a driver that interfaces
with a trusted OS running in some secure environment, for example,
TrustZone on ARM cpus, or a separate secure co-processor etc.
The TEE subsystem can serve a TEE driver for a Global Platform compliant
TEE, but it's not limited to only Global Platform TEEs.
This patch builds on other similar implementations trying to solve
the same problem:
* "optee_linuxdriver" by among others
Jean-michel DELORME<jean-michel.delorme@st.com> and
Emmanuel MICHEL <emmanuel.michel@st.com>
* "Generic TrustZone Driver" by Javier González <javier@javigon.com>
Change-Id: I2336be6189bafb63ca0f49e0a1b16ec75b4514ac
Acked-by: Andreas Dannenberg <dannenberg@ti.com>
Tested-by: Jerome Forissier <jerome.forissier@linaro.org> (HiKey)
Tested-by: Volodymyr Babchuk <vlad.babchuk@gmail.com> (RCAR H3)
Tested-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
(cherry picked from commit 967c9cca2cc50569efc65945325c173cecba83bd)
Signed-off-by: Victor Chong <victor.chong@linaro.org>
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
new file mode 100644
index 0000000..5c60bf4
--- /dev/null
+++ b/drivers/tee/tee_core.c
@@ -0,0 +1,893 @@
+/*
+ * 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");