diff options
Diffstat (limited to 'drivers/tee/tee_core.c')
| -rw-r--r-- | drivers/tee/tee_core.c | 893 |
1 files changed, 893 insertions, 0 deletions
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c new file mode 100644 index 000000000000..5c60bf4423e6 --- /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"); |
