diff options
Diffstat (limited to 'kernel/drivers/misc/mei/main.c')
| -rw-r--r-- | kernel/drivers/misc/mei/main.c | 788 |
1 files changed, 788 insertions, 0 deletions
diff --git a/kernel/drivers/misc/mei/main.c b/kernel/drivers/misc/mei/main.c new file mode 100644 index 000000000..3e2968159 --- /dev/null +++ b/kernel/drivers/misc/mei/main.c @@ -0,0 +1,788 @@ +/* + * + * Intel Management Engine Interface (Intel MEI) Linux driver + * Copyright (c) 2003-2012, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + */ +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/fcntl.h> +#include <linux/poll.h> +#include <linux/init.h> +#include <linux/ioctl.h> +#include <linux/cdev.h> +#include <linux/sched.h> +#include <linux/uuid.h> +#include <linux/compat.h> +#include <linux/jiffies.h> +#include <linux/interrupt.h> + +#include <linux/mei.h> + +#include "mei_dev.h" +#include "client.h" + +/** + * mei_open - the open function + * + * @inode: pointer to inode structure + * @file: pointer to file structure + * + * Return: 0 on success, <0 on error + */ +static int mei_open(struct inode *inode, struct file *file) +{ + struct mei_device *dev; + struct mei_cl *cl; + + int err; + + dev = container_of(inode->i_cdev, struct mei_device, cdev); + if (!dev) + return -ENODEV; + + mutex_lock(&dev->device_lock); + + if (dev->dev_state != MEI_DEV_ENABLED) { + dev_dbg(dev->dev, "dev_state != MEI_ENABLED dev_state = %s\n", + mei_dev_state_str(dev->dev_state)); + err = -ENODEV; + goto err_unlock; + } + + cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY); + if (IS_ERR(cl)) { + err = PTR_ERR(cl); + goto err_unlock; + } + + file->private_data = cl; + + mutex_unlock(&dev->device_lock); + + return nonseekable_open(inode, file); + +err_unlock: + mutex_unlock(&dev->device_lock); + return err; +} + +/** + * mei_release - the release function + * + * @inode: pointer to inode structure + * @file: pointer to file structure + * + * Return: 0 on success, <0 on error + */ +static int mei_release(struct inode *inode, struct file *file) +{ + struct mei_cl *cl = file->private_data; + struct mei_device *dev; + int rets = 0; + + if (WARN_ON(!cl || !cl->dev)) + return -ENODEV; + + dev = cl->dev; + + mutex_lock(&dev->device_lock); + if (cl == &dev->iamthif_cl) { + rets = mei_amthif_release(dev, file); + goto out; + } + if (mei_cl_is_connected(cl)) { + cl->state = MEI_FILE_DISCONNECTING; + cl_dbg(dev, cl, "disconnecting\n"); + rets = mei_cl_disconnect(cl); + } + mei_cl_flush_queues(cl, file); + cl_dbg(dev, cl, "removing\n"); + + mei_cl_unlink(cl); + + file->private_data = NULL; + + kfree(cl); +out: + mutex_unlock(&dev->device_lock); + return rets; +} + + +/** + * mei_read - the read function. + * + * @file: pointer to file structure + * @ubuf: pointer to user buffer + * @length: buffer length + * @offset: data offset in buffer + * + * Return: >=0 data length on success , <0 on error + */ +static ssize_t mei_read(struct file *file, char __user *ubuf, + size_t length, loff_t *offset) +{ + struct mei_cl *cl = file->private_data; + struct mei_device *dev; + struct mei_cl_cb *cb = NULL; + int rets; + int err; + + + if (WARN_ON(!cl || !cl->dev)) + return -ENODEV; + + dev = cl->dev; + + + mutex_lock(&dev->device_lock); + if (dev->dev_state != MEI_DEV_ENABLED) { + rets = -ENODEV; + goto out; + } + + if (length == 0) { + rets = 0; + goto out; + } + + if (cl == &dev->iamthif_cl) { + rets = mei_amthif_read(dev, file, ubuf, length, offset); + goto out; + } + + cb = mei_cl_read_cb(cl, file); + if (cb) { + /* read what left */ + if (cb->buf_idx > *offset) + goto copy_buffer; + /* offset is beyond buf_idx we have no more data return 0 */ + if (cb->buf_idx > 0 && cb->buf_idx <= *offset) { + rets = 0; + goto free; + } + /* Offset needs to be cleaned for contiguous reads*/ + if (cb->buf_idx == 0 && *offset > 0) + *offset = 0; + } else if (*offset > 0) { + *offset = 0; + } + + err = mei_cl_read_start(cl, length, file); + if (err && err != -EBUSY) { + dev_dbg(dev->dev, + "mei start read failure with status = %d\n", err); + rets = err; + goto out; + } + + if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) { + if (file->f_flags & O_NONBLOCK) { + rets = -EAGAIN; + goto out; + } + + mutex_unlock(&dev->device_lock); + + if (wait_event_interruptible(cl->rx_wait, + (!list_empty(&cl->rd_completed)) || + (!mei_cl_is_connected(cl)))) { + + if (signal_pending(current)) + return -EINTR; + return -ERESTARTSYS; + } + + mutex_lock(&dev->device_lock); + if (!mei_cl_is_connected(cl)) { + rets = -EBUSY; + goto out; + } + } + + cb = mei_cl_read_cb(cl, file); + if (!cb) { + rets = 0; + goto out; + } + +copy_buffer: + /* now copy the data to user space */ + if (cb->status) { + rets = cb->status; + dev_dbg(dev->dev, "read operation failed %d\n", rets); + goto free; + } + + dev_dbg(dev->dev, "buf.size = %d buf.idx= %ld\n", + cb->buf.size, cb->buf_idx); + if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) { + rets = -EMSGSIZE; + goto free; + } + + /* length is being truncated to PAGE_SIZE, + * however buf_idx may point beyond that */ + length = min_t(size_t, length, cb->buf_idx - *offset); + + if (copy_to_user(ubuf, cb->buf.data + *offset, length)) { + dev_dbg(dev->dev, "failed to copy data to userland\n"); + rets = -EFAULT; + goto free; + } + + rets = length; + *offset += length; + if ((unsigned long)*offset < cb->buf_idx) + goto out; + +free: + mei_io_cb_free(cb); + +out: + dev_dbg(dev->dev, "end mei read rets= %d\n", rets); + mutex_unlock(&dev->device_lock); + return rets; +} +/** + * mei_write - the write function. + * + * @file: pointer to file structure + * @ubuf: pointer to user buffer + * @length: buffer length + * @offset: data offset in buffer + * + * Return: >=0 data length on success , <0 on error + */ +static ssize_t mei_write(struct file *file, const char __user *ubuf, + size_t length, loff_t *offset) +{ + struct mei_cl *cl = file->private_data; + struct mei_me_client *me_cl = NULL; + struct mei_cl_cb *write_cb = NULL; + struct mei_device *dev; + unsigned long timeout = 0; + int rets; + + if (WARN_ON(!cl || !cl->dev)) + return -ENODEV; + + dev = cl->dev; + + mutex_lock(&dev->device_lock); + + if (dev->dev_state != MEI_DEV_ENABLED) { + rets = -ENODEV; + goto out; + } + + me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id); + if (!me_cl) { + rets = -ENOTTY; + goto out; + } + + if (length == 0) { + rets = 0; + goto out; + } + + if (length > me_cl->props.max_msg_length) { + rets = -EFBIG; + goto out; + } + + if (!mei_cl_is_connected(cl)) { + cl_err(dev, cl, "is not connected"); + rets = -ENODEV; + goto out; + } + if (cl == &dev->iamthif_cl) { + write_cb = mei_amthif_find_read_list_entry(dev, file); + + if (write_cb) { + timeout = write_cb->read_time + + mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER); + + if (time_after(jiffies, timeout)) { + *offset = 0; + mei_io_cb_free(write_cb); + write_cb = NULL; + } + } + } + + *offset = 0; + write_cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file); + if (!write_cb) { + rets = -ENOMEM; + goto out; + } + + rets = copy_from_user(write_cb->buf.data, ubuf, length); + if (rets) { + dev_dbg(dev->dev, "failed to copy data from userland\n"); + rets = -EFAULT; + goto out; + } + + if (cl == &dev->iamthif_cl) { + rets = mei_amthif_write(cl, write_cb); + + if (rets) { + dev_err(dev->dev, + "amthif write failed with status = %d\n", rets); + goto out; + } + mei_me_cl_put(me_cl); + mutex_unlock(&dev->device_lock); + return length; + } + + rets = mei_cl_write(cl, write_cb, false); +out: + mei_me_cl_put(me_cl); + mutex_unlock(&dev->device_lock); + if (rets < 0) + mei_io_cb_free(write_cb); + return rets; +} + +/** + * mei_ioctl_connect_client - the connect to fw client IOCTL function + * + * @file: private data of the file object + * @data: IOCTL connect data, input and output parameters + * + * Locking: called under "dev->device_lock" lock + * + * Return: 0 on success, <0 on failure. + */ +static int mei_ioctl_connect_client(struct file *file, + struct mei_connect_client_data *data) +{ + struct mei_device *dev; + struct mei_client *client; + struct mei_me_client *me_cl; + struct mei_cl *cl; + int rets; + + cl = file->private_data; + dev = cl->dev; + + if (dev->dev_state != MEI_DEV_ENABLED) + return -ENODEV; + + if (cl->state != MEI_FILE_INITIALIZING && + cl->state != MEI_FILE_DISCONNECTED) + return -EBUSY; + + /* find ME client we're trying to connect to */ + me_cl = mei_me_cl_by_uuid(dev, &data->in_client_uuid); + if (!me_cl || me_cl->props.fixed_address) { + dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n", + &data->in_client_uuid); + return -ENOTTY; + } + + cl->me_client_id = me_cl->client_id; + cl->cl_uuid = me_cl->props.protocol_name; + + dev_dbg(dev->dev, "Connect to FW Client ID = %d\n", + cl->me_client_id); + dev_dbg(dev->dev, "FW Client - Protocol Version = %d\n", + me_cl->props.protocol_version); + dev_dbg(dev->dev, "FW Client - Max Msg Len = %d\n", + me_cl->props.max_msg_length); + + /* if we're connecting to amthif client then we will use the + * existing connection + */ + if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) { + dev_dbg(dev->dev, "FW Client is amthi\n"); + if (!mei_cl_is_connected(&dev->iamthif_cl)) { + rets = -ENODEV; + goto end; + } + mei_cl_unlink(cl); + + kfree(cl); + cl = NULL; + dev->iamthif_open_count++; + file->private_data = &dev->iamthif_cl; + + client = &data->out_client_properties; + client->max_msg_length = me_cl->props.max_msg_length; + client->protocol_version = me_cl->props.protocol_version; + rets = dev->iamthif_cl.status; + + goto end; + } + + /* prepare the output buffer */ + client = &data->out_client_properties; + client->max_msg_length = me_cl->props.max_msg_length; + client->protocol_version = me_cl->props.protocol_version; + dev_dbg(dev->dev, "Can connect?\n"); + + rets = mei_cl_connect(cl, file); + +end: + mei_me_cl_put(me_cl); + return rets; +} + +/** + * mei_ioctl - the IOCTL function + * + * @file: pointer to file structure + * @cmd: ioctl command + * @data: pointer to mei message structure + * + * Return: 0 on success , <0 on error + */ +static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data) +{ + struct mei_device *dev; + struct mei_cl *cl = file->private_data; + struct mei_connect_client_data connect_data; + int rets; + + + if (WARN_ON(!cl || !cl->dev)) + return -ENODEV; + + dev = cl->dev; + + dev_dbg(dev->dev, "IOCTL cmd = 0x%x", cmd); + + mutex_lock(&dev->device_lock); + if (dev->dev_state != MEI_DEV_ENABLED) { + rets = -ENODEV; + goto out; + } + + switch (cmd) { + case IOCTL_MEI_CONNECT_CLIENT: + dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n"); + if (copy_from_user(&connect_data, (char __user *)data, + sizeof(struct mei_connect_client_data))) { + dev_dbg(dev->dev, "failed to copy data from userland\n"); + rets = -EFAULT; + goto out; + } + + rets = mei_ioctl_connect_client(file, &connect_data); + if (rets) + goto out; + + /* if all is ok, copying the data back to user. */ + if (copy_to_user((char __user *)data, &connect_data, + sizeof(struct mei_connect_client_data))) { + dev_dbg(dev->dev, "failed to copy data to userland\n"); + rets = -EFAULT; + goto out; + } + + break; + + default: + dev_err(dev->dev, ": unsupported ioctl %d.\n", cmd); + rets = -ENOIOCTLCMD; + } + +out: + mutex_unlock(&dev->device_lock); + return rets; +} + +/** + * mei_compat_ioctl - the compat IOCTL function + * + * @file: pointer to file structure + * @cmd: ioctl command + * @data: pointer to mei message structure + * + * Return: 0 on success , <0 on error + */ +#ifdef CONFIG_COMPAT +static long mei_compat_ioctl(struct file *file, + unsigned int cmd, unsigned long data) +{ + return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data)); +} +#endif + + +/** + * mei_poll - the poll function + * + * @file: pointer to file structure + * @wait: pointer to poll_table structure + * + * Return: poll mask + */ +static unsigned int mei_poll(struct file *file, poll_table *wait) +{ + unsigned long req_events = poll_requested_events(wait); + struct mei_cl *cl = file->private_data; + struct mei_device *dev; + unsigned int mask = 0; + + if (WARN_ON(!cl || !cl->dev)) + return POLLERR; + + dev = cl->dev; + + mutex_lock(&dev->device_lock); + + + if (dev->dev_state != MEI_DEV_ENABLED || + !mei_cl_is_connected(cl)) { + mask = POLLERR; + goto out; + } + + if (cl == &dev->iamthif_cl) { + mask = mei_amthif_poll(dev, file, wait); + goto out; + } + + if (req_events & (POLLIN | POLLRDNORM)) { + poll_wait(file, &cl->rx_wait, wait); + + if (!list_empty(&cl->rd_completed)) + mask |= POLLIN | POLLRDNORM; + else + mei_cl_read_start(cl, 0, file); + } + +out: + mutex_unlock(&dev->device_lock); + return mask; +} + +/** + * fw_status_show - mei device attribute show method + * + * @device: device pointer + * @attr: attribute pointer + * @buf: char out buffer + * + * Return: number of the bytes printed into buf or error + */ +static ssize_t fw_status_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct mei_device *dev = dev_get_drvdata(device); + struct mei_fw_status fw_status; + int err, i; + ssize_t cnt = 0; + + mutex_lock(&dev->device_lock); + err = mei_fw_status(dev, &fw_status); + mutex_unlock(&dev->device_lock); + if (err) { + dev_err(device, "read fw_status error = %d\n", err); + return err; + } + + for (i = 0; i < fw_status.count; i++) + cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n", + fw_status.status[i]); + return cnt; +} +static DEVICE_ATTR_RO(fw_status); + +static struct attribute *mei_attrs[] = { + &dev_attr_fw_status.attr, + NULL +}; +ATTRIBUTE_GROUPS(mei); + +/* + * file operations structure will be used for mei char device. + */ +static const struct file_operations mei_fops = { + .owner = THIS_MODULE, + .read = mei_read, + .unlocked_ioctl = mei_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = mei_compat_ioctl, +#endif + .open = mei_open, + .release = mei_release, + .write = mei_write, + .poll = mei_poll, + .llseek = no_llseek +}; + +static struct class *mei_class; +static dev_t mei_devt; +#define MEI_MAX_DEVS MINORMASK +static DEFINE_MUTEX(mei_minor_lock); +static DEFINE_IDR(mei_idr); + +/** + * mei_minor_get - obtain next free device minor number + * + * @dev: device pointer + * + * Return: allocated minor, or -ENOSPC if no free minor left + */ +static int mei_minor_get(struct mei_device *dev) +{ + int ret; + + mutex_lock(&mei_minor_lock); + ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL); + if (ret >= 0) + dev->minor = ret; + else if (ret == -ENOSPC) + dev_err(dev->dev, "too many mei devices\n"); + + mutex_unlock(&mei_minor_lock); + return ret; +} + +/** + * mei_minor_free - mark device minor number as free + * + * @dev: device pointer + */ +static void mei_minor_free(struct mei_device *dev) +{ + mutex_lock(&mei_minor_lock); + idr_remove(&mei_idr, dev->minor); + mutex_unlock(&mei_minor_lock); +} + +int mei_register(struct mei_device *dev, struct device *parent) +{ + struct device *clsdev; /* class device */ + int ret, devno; + + ret = mei_minor_get(dev); + if (ret < 0) + return ret; + + /* Fill in the data structures */ + devno = MKDEV(MAJOR(mei_devt), dev->minor); + cdev_init(&dev->cdev, &mei_fops); + dev->cdev.owner = mei_fops.owner; + + /* Add the device */ + ret = cdev_add(&dev->cdev, devno, 1); + if (ret) { + dev_err(parent, "unable to add device %d:%d\n", + MAJOR(mei_devt), dev->minor); + goto err_dev_add; + } + + clsdev = device_create_with_groups(mei_class, parent, devno, + dev, mei_groups, + "mei%d", dev->minor); + + if (IS_ERR(clsdev)) { + dev_err(parent, "unable to create device %d:%d\n", + MAJOR(mei_devt), dev->minor); + ret = PTR_ERR(clsdev); + goto err_dev_create; + } + + ret = mei_dbgfs_register(dev, dev_name(clsdev)); + if (ret) { + dev_err(clsdev, "cannot register debugfs ret = %d\n", ret); + goto err_dev_dbgfs; + } + + return 0; + +err_dev_dbgfs: + device_destroy(mei_class, devno); +err_dev_create: + cdev_del(&dev->cdev); +err_dev_add: + mei_minor_free(dev); + return ret; +} +EXPORT_SYMBOL_GPL(mei_register); + +void mei_deregister(struct mei_device *dev) +{ + int devno; + + devno = dev->cdev.dev; + cdev_del(&dev->cdev); + + mei_dbgfs_deregister(dev); + + device_destroy(mei_class, devno); + + mei_minor_free(dev); +} +EXPORT_SYMBOL_GPL(mei_deregister); + +static int __init mei_init(void) +{ + int ret; + + mei_class = class_create(THIS_MODULE, "mei"); + if (IS_ERR(mei_class)) { + pr_err("couldn't create class\n"); + ret = PTR_ERR(mei_class); + goto err; + } + + ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei"); + if (ret < 0) { + pr_err("unable to allocate char dev region\n"); + goto err_class; + } + + ret = mei_cl_bus_init(); + if (ret < 0) { + pr_err("unable to initialize bus\n"); + goto err_chrdev; + } + + return 0; + +err_chrdev: + unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); +err_class: + class_destroy(mei_class); +err: + return ret; +} + +static void __exit mei_exit(void) +{ + unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); + class_destroy(mei_class); + mei_cl_bus_exit(); +} + +module_init(mei_init); +module_exit(mei_exit); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_DESCRIPTION("Intel(R) Management Engine Interface"); +MODULE_LICENSE("GPL v2"); + |