[deliverable/linux.git] / drivers / misc / mei / main.c

/*
 *
 * 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.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/aio.h>
#include <linux/pci.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/miscdevice.h>

#include <linux/mei.h>

#include "mei_dev.h"
#include "hw-me.h"
#include "client.h"

/**
 * mei_open - the open function
 *
 * @inode: pointer to inode structure
 * @file: pointer to file structure
 e
 * returns 0 on success, <0 on error
 */
static int mei_open(struct inode *inode, struct file *file)
{
	struct miscdevice *misc = file->private_data;
	struct pci_dev *pdev;
	struct mei_cl *cl;
	struct mei_device *dev;

	int err;

	err = -ENODEV;
	if (!misc->parent)
		goto out;

	pdev = container_of(misc->parent, struct pci_dev, dev);

	dev = pci_get_drvdata(pdev);
	if (!dev)
		goto out;

	mutex_lock(&dev->device_lock);
	err = -ENOMEM;
	cl = mei_cl_allocate(dev);
	if (!cl)
		goto out_unlock;

	err = -ENODEV;
	if (dev->dev_state != MEI_DEV_ENABLED) {
		dev_dbg(&dev->pdev->dev, "dev_state != MEI_ENABLED  dev_state = %s\n",
		    mei_dev_state_str(dev->dev_state));
		goto out_unlock;
	}
	err = -EMFILE;
	if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
		dev_err(&dev->pdev->dev, "open_handle_count exceded %d",
			MEI_MAX_OPEN_HANDLE_COUNT);
		goto out_unlock;
	}

	err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
	if (err)
		goto out_unlock;

	file->private_data = cl;
	mutex_unlock(&dev->device_lock);

	return nonseekable_open(inode, file);

out_unlock:
	mutex_unlock(&dev->device_lock);
	kfree(cl);
out:
	return err;
}

/**
 * mei_release - the release function
 *
 * @inode: pointer to inode structure
 * @file: pointer to file structure
 *
 * returns 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_cl_cb *cb;
	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 (cl->state == MEI_FILE_CONNECTED) {
		cl->state = MEI_FILE_DISCONNECTING;
		dev_dbg(&dev->pdev->dev,
			"disconnecting client host client = %d, "
		    "ME client = %d\n",
		    cl->host_client_id,
		    cl->me_client_id);
		rets = mei_cl_disconnect(cl);
	}
	mei_cl_flush_queues(cl);
	dev_dbg(&dev->pdev->dev, "remove client host client = %d, ME client = %d\n",
	    cl->host_client_id,
	    cl->me_client_id);

	if (dev->open_handle_count > 0) {
		clear_bit(cl->host_client_id, dev->host_clients_map);
		dev->open_handle_count--;
	}
	mei_cl_unlink(cl);


	/* free read cb */
	cb = NULL;
	if (cl->read_cb) {
		cb = mei_cl_find_read_cb(cl);
		/* Remove entry from read list */
		if (cb)
			list_del(&cb->list);

		cb = cl->read_cb;
		cl->read_cb = NULL;
	}

	file->private_data = NULL;

	mei_io_cb_free(cb);

	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
 *
 * returns >=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_cl_cb *cb_pos = NULL;
	struct mei_cl_cb *cb = NULL;
	struct mei_device *dev;
	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;
	}

	if (cl->read_cb) {
		cb = cl->read_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);
	if (err && err != -EBUSY) {
		dev_dbg(&dev->pdev->dev,
			"mei start read failure with status = %d\n", err);
		rets = err;
		goto out;
	}

	if (MEI_READ_COMPLETE != cl->reading_state &&
			!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,
				MEI_READ_COMPLETE == cl->reading_state ||
				mei_cl_is_transitioning(cl))) {

			if (signal_pending(current))
				return -EINTR;
			return -ERESTARTSYS;
		}

		mutex_lock(&dev->device_lock);
		if (mei_cl_is_transitioning(cl)) {
			rets = -EBUSY;
			goto out;
		}
	}

	cb = cl->read_cb;

	if (!cb) {
		rets = -ENODEV;
		goto out;
	}
	if (cl->reading_state != MEI_READ_COMPLETE) {
		rets = 0;
		goto out;
	}
	/* now copy the data to user space */
copy_buffer:
	dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
	    cb->response_buffer.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->response_buffer.data + *offset, length)) {
		rets = -EFAULT;
		goto free;
	}

	rets = length;
	*offset += length;
	if ((unsigned long)*offset < cb->buf_idx)
		goto out;

free:
	cb_pos = mei_cl_find_read_cb(cl);
	/* Remove entry from read list */
	if (cb_pos)
		list_del(&cb_pos->list);
	mei_io_cb_free(cb);
	cl->reading_state = MEI_IDLE;
	cl->read_cb = NULL;
out:
	dev_dbg(&dev->pdev->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
 *
 * returns >=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_cl_cb *write_cb = NULL;
	struct mei_device *dev;
	unsigned long timeout = 0;
	int rets;
	int id;

	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;
	}

	id = mei_me_cl_by_id(dev, cl->me_client_id);
	if (id < 0) {
		rets = -ENODEV;
		goto out;
	}

	if (length == 0) {
		rets = 0;
		goto out;
	}

	if (length > dev->me_clients[id].props.max_msg_length) {
		rets = -EFBIG;
		goto out;
	}

	if (cl->state != MEI_FILE_CONNECTED) {
		dev_err(&dev->pdev->dev, "host client = %d,  is not connected to ME client = %d",
			cl->host_client_id, cl->me_client_id);
		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) ||
			    cl->reading_state == MEI_READ_COMPLETE) {
				*offset = 0;
				list_del(&write_cb->list);
				mei_io_cb_free(write_cb);
				write_cb = NULL;
			}
		}
	}

	/* free entry used in read */
	if (cl->reading_state == MEI_READ_COMPLETE) {
		*offset = 0;
		write_cb = mei_cl_find_read_cb(cl);
		if (write_cb) {
			list_del(&write_cb->list);
			mei_io_cb_free(write_cb);
			write_cb = NULL;
			cl->reading_state = MEI_IDLE;
			cl->read_cb = NULL;
		}
	} else if (cl->reading_state == MEI_IDLE)
		*offset = 0;


	write_cb = mei_io_cb_init(cl, file);
	if (!write_cb) {
		dev_err(&dev->pdev->dev, "write cb allocation failed\n");
		rets = -ENOMEM;
		goto out;
	}
	rets = mei_io_cb_alloc_req_buf(write_cb, length);
	if (rets)
		goto out;

	rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
	if (rets) {
		dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
		rets = -EFAULT;
		goto out;
	}

	if (cl == &dev->iamthif_cl) {
		rets = mei_amthif_write(dev, write_cb);

		if (rets) {
			dev_err(&dev->pdev->dev,
				"amthif write failed with status = %d\n", rets);
			goto out;
		}
		mutex_unlock(&dev->device_lock);
		return length;
	}

	rets = mei_cl_write(cl, write_cb, false);
out:
	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
 *
 * @dev: the device structure
 * @data: IOCTL connect data, input and output parameters
 * @file: private data of the file object
 *
 * Locking: called under "dev->device_lock" lock
 *
 * returns 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_cl *cl;
	int i;
	int rets;

	cl = file->private_data;
	if (WARN_ON(!cl || !cl->dev))
		return -ENODEV;

	dev = cl->dev;

	if (dev->dev_state != MEI_DEV_ENABLED) {
		rets = -ENODEV;
		goto end;
	}

	if (cl->state != MEI_FILE_INITIALIZING &&
	    cl->state != MEI_FILE_DISCONNECTED) {
		rets = -EBUSY;
		goto end;
	}

	/* find ME client we're trying to connect to */
	i = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
	if (i < 0 || dev->me_clients[i].props.fixed_address) {
		dev_dbg(&dev->pdev->dev, "Cannot connect to FW Client UUID = %pUl\n",
				&data->in_client_uuid);
		rets = -ENODEV;
		goto end;
	}

	cl->me_client_id = dev->me_clients[i].client_id;
	cl->state = MEI_FILE_CONNECTING;

	dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
			cl->me_client_id);
	dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
			dev->me_clients[i].props.protocol_version);
	dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
			dev->me_clients[i].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->pdev->dev, "FW Client is amthi\n");
		if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
			rets = -ENODEV;
			goto end;
		}
		clear_bit(cl->host_client_id, dev->host_clients_map);
		mei_cl_unlink(cl);

		kfree(cl);
		cl = NULL;
		file->private_data = &dev->iamthif_cl;

		client = &data->out_client_properties;
		client->max_msg_length =
			dev->me_clients[i].props.max_msg_length;
		client->protocol_version =
			dev->me_clients[i].props.protocol_version;
		rets = dev->iamthif_cl.status;

		goto end;
	}


	/* prepare the output buffer */
	client = &data->out_client_properties;
	client->max_msg_length = dev->me_clients[i].props.max_msg_length;
	client->protocol_version = dev->me_clients[i].props.protocol_version;
	dev_dbg(&dev->pdev->dev, "Can connect?\n");


	rets = mei_cl_connect(cl, file);

end:
	return rets;
}


/**
 * mei_ioctl - the IOCTL function
 *
 * @file: pointer to file structure
 * @cmd: ioctl command
 * @data: pointer to mei message structure
 *
 * returns 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 = NULL;
	int rets;

	if (cmd != IOCTL_MEI_CONNECT_CLIENT)
		return -EINVAL;

	if (WARN_ON(!cl || !cl->dev))
		return -ENODEV;

	dev = cl->dev;

	dev_dbg(&dev->pdev->dev, "IOCTL cmd = 0x%x", cmd);

	mutex_lock(&dev->device_lock);
	if (dev->dev_state != MEI_DEV_ENABLED) {
		rets = -ENODEV;
		goto out;
	}

	dev_dbg(&dev->pdev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");

	connect_data = kzalloc(sizeof(struct mei_connect_client_data),
							GFP_KERNEL);
	if (!connect_data) {
		rets = -ENOMEM;
		goto out;
	}
	dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
	if (copy_from_user(connect_data, (char __user *)data,
				sizeof(struct mei_connect_client_data))) {
		dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
		rets = -EFAULT;
		goto out;
	}

	rets = mei_ioctl_connect_client(file, connect_data);

	/* if all is ok, copying the data back to user. */
	if (rets)
		goto out;

	dev_dbg(&dev->pdev->dev, "copy connect data to user\n");
	if (copy_to_user((char __user *)data, connect_data,
				sizeof(struct mei_connect_client_data))) {
		dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
		rets = -EFAULT;
		goto out;
	}

out:
	kfree(connect_data);
	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
 *
 * returns 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
 *
 * returns poll mask
 */
static unsigned int mei_poll(struct file *file, poll_table *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 (!mei_cl_is_connected(cl)) {
		mask = POLLERR;
		goto out;
	}

	mutex_unlock(&dev->device_lock);


	if (cl == &dev->iamthif_cl)
		return mei_amthif_poll(dev, file, wait);

	poll_wait(file, &cl->tx_wait, wait);

	mutex_lock(&dev->device_lock);

	if (!mei_cl_is_connected(cl)) {
		mask = POLLERR;
		goto out;
	}

	if (MEI_WRITE_COMPLETE == cl->writing_state)
		mask |= (POLLIN | POLLRDNORM);

out:
	mutex_unlock(&dev->device_lock);
	return mask;
}

/*
 * 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
};

/*
 * Misc Device Struct
 */
static struct miscdevice  mei_misc_device = {
		.name = "mei",
		.fops = &mei_fops,
		.minor = MISC_DYNAMIC_MINOR,
};


int mei_register(struct mei_device *dev)
{
	int ret;
	mei_misc_device.parent = &dev->pdev->dev;
	ret = misc_register(&mei_misc_device);
	if (ret)
		return ret;

	if (mei_dbgfs_register(dev, mei_misc_device.name))
		dev_err(&dev->pdev->dev, "cannot register debugfs\n");

	return 0;
}
EXPORT_SYMBOL_GPL(mei_register);

void mei_deregister(struct mei_device *dev)
{
	mei_dbgfs_deregister(dev);
	misc_deregister(&mei_misc_device);
	mei_misc_device.parent = NULL;
}
EXPORT_SYMBOL_GPL(mei_deregister);

static int __init mei_init(void)
{
	return mei_cl_bus_init();
}

static void __exit mei_exit(void)
{
	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");
Commit	Line	Data
ab841160 OW	1	/*
	2	*
	3	* Intel Management Engine Interface (Intel MEI) Linux driver
733ba91c	4	* Copyright (c) 2003-2012, Intel Corporation.
ab841160 OW	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms and conditions of the GNU General Public License,
	8	* version 2, as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope it will be useful, but WITHOUT
	11	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	12	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	13	* more details.
	14	*
	15	*/
	16
2f3d2b49 TW	17	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
2f3d2b49 TW	18
ab841160 OW	19	#include <linux/module.h>
	20	#include <linux/moduleparam.h>
	21	#include <linux/kernel.h>
	22	#include <linux/device.h>
	23	#include <linux/fs.h>
	24	#include <linux/errno.h>
	25	#include <linux/types.h>
	26	#include <linux/fcntl.h>
	27	#include <linux/aio.h>
	28	#include <linux/pci.h>
	29	#include <linux/poll.h>
	30	#include <linux/init.h>
	31	#include <linux/ioctl.h>
	32	#include <linux/cdev.h>
ab841160 OW	33	#include <linux/sched.h>
	34	#include <linux/uuid.h>
	35	#include <linux/compat.h>
	36	#include <linux/jiffies.h>
	37	#include <linux/interrupt.h>
5b881e3c	38	#include <linux/miscdevice.h>
ab841160	39
4f3afe1d	40	#include <linux/mei.h>
47a73801 TW	41
47a73801 TW	42	#include "mei_dev.h"
9dc64d6a	43	#include "hw-me.h"
90e0b5f1	44	#include "client.h"
ab841160	45
ab841160 OW	46	/**
	47	* mei_open - the open function
	48	*
	49	* @inode: pointer to inode structure
	50	* @file: pointer to file structure
9b0d5efc	51	e
ab841160 OW	52	* returns 0 on success, <0 on error
	53	*/
	54	static int mei_open(struct inode inode, struct file file)
	55	{
2703d4b2 TW	56	struct miscdevice *misc = file->private_data;
2703d4b2 TW	57	struct pci_dev *pdev;
ab841160	58	struct mei_cl *cl;
ab841160	59	struct mei_device *dev;
2703d4b2	60
6f37aca8	61	int err;
ab841160 OW	62
ab841160 OW	63	err = -ENODEV;
2703d4b2	64	if (!misc->parent)
ab841160 OW	65	goto out;
ab841160 OW	66
2703d4b2 TW	67	pdev = container_of(misc->parent, struct pci_dev, dev);
	68
	69	dev = pci_get_drvdata(pdev);
5b881e3c	70	if (!dev)
ab841160 OW	71	goto out;
	72
	73	mutex_lock(&dev->device_lock);
	74	err = -ENOMEM;
c95efb74	75	cl = mei_cl_allocate(dev);
ab841160	76	if (!cl)
303dfbf5	77	goto out_unlock;
ab841160 OW	78
ab841160 OW	79	err = -ENODEV;
b210d750 TW	80	if (dev->dev_state != MEI_DEV_ENABLED) {
	81	dev_dbg(&dev->pdev->dev, "dev_state != MEI_ENABLED dev_state = %s\n",
	82	mei_dev_state_str(dev->dev_state));
ab841160 OW	83	goto out_unlock;
	84	}
	85	err = -EMFILE;
1b812947 TW	86	if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
	87	dev_err(&dev->pdev->dev, "open_handle_count exceded %d",
	88	MEI_MAX_OPEN_HANDLE_COUNT);
ab841160	89	goto out_unlock;
1b812947	90	}
ab841160	91
781d0d89 TW	92	err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
781d0d89 TW	93	if (err)
ab841160	94	goto out_unlock;
ab841160 OW	95
	96	file->private_data = cl;
	97	mutex_unlock(&dev->device_lock);
	98
5b881e3c	99	return nonseekable_open(inode, file);
ab841160 OW	100
	101	out_unlock:
	102	mutex_unlock(&dev->device_lock);
	103	kfree(cl);
	104	out:
	105	return err;
	106	}
	107
	108	/**
	109	* mei_release - the release function
	110	*
	111	* @inode: pointer to inode structure
	112	* @file: pointer to file structure
	113	*
	114	* returns 0 on success, <0 on error
	115	*/
	116	static int mei_release(struct inode inode, struct file file)
	117	{
	118	struct mei_cl *cl = file->private_data;
	119	struct mei_cl_cb *cb;
	120	struct mei_device *dev;
	121	int rets = 0;
	122
	123	if (WARN_ON(!cl \|\| !cl->dev))
	124	return -ENODEV;
	125
	126	dev = cl->dev;
	127
	128	mutex_lock(&dev->device_lock);
a562d5c2 TW	129	if (cl == &dev->iamthif_cl) {
	130	rets = mei_amthif_release(dev, file);
	131	goto out;
	132	}
	133	if (cl->state == MEI_FILE_CONNECTED) {
	134	cl->state = MEI_FILE_DISCONNECTING;
	135	dev_dbg(&dev->pdev->dev,
	136	"disconnecting client host client = %d, "
	137	"ME client = %d\n",
ab841160 OW	138	cl->host_client_id,
ab841160 OW	139	cl->me_client_id);
90e0b5f1	140	rets = mei_cl_disconnect(cl);
a562d5c2 TW	141	}
	142	mei_cl_flush_queues(cl);
	143	dev_dbg(&dev->pdev->dev, "remove client host client = %d, ME client = %d\n",
	144	cl->host_client_id,
	145	cl->me_client_id);
	146
	147	if (dev->open_handle_count > 0) {
	148	clear_bit(cl->host_client_id, dev->host_clients_map);
	149	dev->open_handle_count--;
	150	}
90e0b5f1	151	mei_cl_unlink(cl);
a562d5c2	152
781d0d89	153
a562d5c2 TW	154	/* free read cb */
	155	cb = NULL;
	156	if (cl->read_cb) {
90e0b5f1	157	cb = mei_cl_find_read_cb(cl);
a562d5c2 TW	158	/* Remove entry from read list */
	159	if (cb)
	160	list_del(&cb->list);
	161
	162	cb = cl->read_cb;
	163	cl->read_cb = NULL;
	164	}
ab841160	165
a562d5c2	166	file->private_data = NULL;
ab841160	167
a9c8a17a	168	mei_io_cb_free(cb);
a562d5c2 TW	169
	170	kfree(cl);
	171	out:
ab841160 OW	172	mutex_unlock(&dev->device_lock);
	173	return rets;
	174	}
	175
	176
	177	/**
	178	* mei_read - the read function.
	179	*
	180	* @file: pointer to file structure
	181	* @ubuf: pointer to user buffer
	182	* @length: buffer length
	183	* @offset: data offset in buffer
	184	*
	185	* returns >=0 data length on success , <0 on error
	186	*/
	187	static ssize_t mei_read(struct file file, char __user ubuf,
441ab50f	188	size_t length, loff_t *offset)
ab841160 OW	189	{
	190	struct mei_cl *cl = file->private_data;
	191	struct mei_cl_cb *cb_pos = NULL;
	192	struct mei_cl_cb *cb = NULL;
	193	struct mei_device *dev;
ab841160 OW	194	int rets;
	195	int err;
	196
	197
	198	if (WARN_ON(!cl \|\| !cl->dev))
	199	return -ENODEV;
	200
	201	dev = cl->dev;
	202
dd5de1f1	203
ab841160	204	mutex_lock(&dev->device_lock);
b210d750	205	if (dev->dev_state != MEI_DEV_ENABLED) {
ab841160 OW	206	rets = -ENODEV;
	207	goto out;
	208	}
	209
dd5de1f1 TW	210	if (length == 0) {
	211	rets = 0;
	212	goto out;
	213	}
	214
ab841160	215	if (cl == &dev->iamthif_cl) {
19838fb8	216	rets = mei_amthif_read(dev, file, ubuf, length, offset);
ab841160 OW	217	goto out;
	218	}
	219
139aacf7	220	if (cl->read_cb) {
ab841160	221	cb = cl->read_cb;
139aacf7 TW	222	/* read what left */
	223	if (cb->buf_idx > *offset)
	224	goto copy_buffer;
	225	/* offset is beyond buf_idx we have no more data return 0 */
	226	if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
	227	rets = 0;
	228	goto free;
	229	}
	230	/* Offset needs to be cleaned for contiguous reads*/
	231	if (cb->buf_idx == 0 && *offset > 0)
	232	*offset = 0;
	233	} else if (*offset > 0) {
ab841160	234	*offset = 0;
ab841160 OW	235	}
ab841160 OW	236
fcb136e1	237	err = mei_cl_read_start(cl, length);
ab841160 OW	238	if (err && err != -EBUSY) {
	239	dev_dbg(&dev->pdev->dev,
	240	"mei start read failure with status = %d\n", err);
	241	rets = err;
	242	goto out;
	243	}
	244
	245	if (MEI_READ_COMPLETE != cl->reading_state &&
	246	!waitqueue_active(&cl->rx_wait)) {
	247	if (file->f_flags & O_NONBLOCK) {
	248	rets = -EAGAIN;
	249	goto out;
	250	}
	251
	252	mutex_unlock(&dev->device_lock);
	253
	254	if (wait_event_interruptible(cl->rx_wait,
e2b31644 TW	255	MEI_READ_COMPLETE == cl->reading_state \|\|
	256	mei_cl_is_transitioning(cl))) {
	257
ab841160 OW	258	if (signal_pending(current))
	259	return -EINTR;
	260	return -ERESTARTSYS;
	261	}
	262
	263	mutex_lock(&dev->device_lock);
e2b31644	264	if (mei_cl_is_transitioning(cl)) {
ab841160 OW	265	rets = -EBUSY;
	266	goto out;
	267	}
	268	}
	269
	270	cb = cl->read_cb;
	271
	272	if (!cb) {
	273	rets = -ENODEV;
	274	goto out;
	275	}
	276	if (cl->reading_state != MEI_READ_COMPLETE) {
	277	rets = 0;
	278	goto out;
	279	}
	280	/* now copy the data to user space */
	281	copy_buffer:
fcb136e1 TW	282	dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
fcb136e1 TW	283	cb->response_buffer.size, cb->buf_idx);
ebb108ef	284	if (length == 0 \|\| ubuf == NULL \|\| *offset > cb->buf_idx) {
ab841160 OW	285	rets = -EMSGSIZE;
	286	goto free;
	287	}
	288
ebb108ef TW	289	/* length is being truncated to PAGE_SIZE,
	290	* however buf_idx may point beyond that */
	291	length = min_t(size_t, length, cb->buf_idx - *offset);
ab841160	292
441ab50f	293	if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
ab841160 OW	294	rets = -EFAULT;
	295	goto free;
	296	}
	297
	298	rets = length;
	299	*offset += length;
ebb108ef	300	if ((unsigned long)*offset < cb->buf_idx)
ab841160 OW	301	goto out;
	302
	303	free:
90e0b5f1	304	cb_pos = mei_cl_find_read_cb(cl);
ab841160 OW	305	/* Remove entry from read list */
ab841160 OW	306	if (cb_pos)
fb601adb	307	list_del(&cb_pos->list);
601a1efa	308	mei_io_cb_free(cb);
ab841160 OW	309	cl->reading_state = MEI_IDLE;
ab841160 OW	310	cl->read_cb = NULL;
ab841160 OW	311	out:
	312	dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
	313	mutex_unlock(&dev->device_lock);
	314	return rets;
	315	}
ab841160 OW	316	/**
	317	* mei_write - the write function.
	318	*
	319	* @file: pointer to file structure
	320	* @ubuf: pointer to user buffer
	321	* @length: buffer length
	322	* @offset: data offset in buffer
	323	*
	324	* returns >=0 data length on success , <0 on error
	325	*/
	326	static ssize_t mei_write(struct file file, const char __user ubuf,
441ab50f	327	size_t length, loff_t *offset)
ab841160 OW	328	{
	329	struct mei_cl *cl = file->private_data;
	330	struct mei_cl_cb *write_cb = NULL;
ab841160 OW	331	struct mei_device *dev;
	332	unsigned long timeout = 0;
	333	int rets;
4234a6de	334	int id;
ab841160 OW	335
	336	if (WARN_ON(!cl \|\| !cl->dev))
	337	return -ENODEV;
	338
	339	dev = cl->dev;
	340
	341	mutex_lock(&dev->device_lock);
	342
b210d750	343	if (dev->dev_state != MEI_DEV_ENABLED) {
75f0ee15	344	rets = -ENODEV;
4234a6de	345	goto out;
ab841160 OW	346	}
ab841160 OW	347
4234a6de TW	348	id = mei_me_cl_by_id(dev, cl->me_client_id);
4234a6de TW	349	if (id < 0) {
75f0ee15	350	rets = -ENODEV;
4234a6de	351	goto out;
75f0ee15	352	}
dd5de1f1 TW	353
	354	if (length == 0) {
	355	rets = 0;
	356	goto out;
	357	}
	358
	359	if (length > dev->me_clients[id].props.max_msg_length) {
	360	rets = -EFBIG;
4234a6de	361	goto out;
75f0ee15 TW	362	}
	363
	364	if (cl->state != MEI_FILE_CONNECTED) {
75f0ee15 TW	365	dev_err(&dev->pdev->dev, "host client = %d, is not connected to ME client = %d",
75f0ee15 TW	366	cl->host_client_id, cl->me_client_id);
4234a6de TW	367	rets = -ENODEV;
4234a6de TW	368	goto out;
75f0ee15	369	}
ab841160	370	if (cl == &dev->iamthif_cl) {
19838fb8	371	write_cb = mei_amthif_find_read_list_entry(dev, file);
ab841160 OW	372
	373	if (write_cb) {
	374	timeout = write_cb->read_time +
3870c320	375	mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
ab841160 OW	376
ab841160 OW	377	if (time_after(jiffies, timeout) \|\|
75f0ee15 TW	378	cl->reading_state == MEI_READ_COMPLETE) {
75f0ee15 TW	379	*offset = 0;
fb601adb	380	list_del(&write_cb->list);
601a1efa	381	mei_io_cb_free(write_cb);
75f0ee15	382	write_cb = NULL;
ab841160 OW	383	}
	384	}
	385	}
	386
	387	/* free entry used in read */
	388	if (cl->reading_state == MEI_READ_COMPLETE) {
	389	*offset = 0;
90e0b5f1	390	write_cb = mei_cl_find_read_cb(cl);
ab841160	391	if (write_cb) {
fb601adb	392	list_del(&write_cb->list);
601a1efa	393	mei_io_cb_free(write_cb);
ab841160 OW	394	write_cb = NULL;
	395	cl->reading_state = MEI_IDLE;
	396	cl->read_cb = NULL;
ab841160	397	}
d91aaed3	398	} else if (cl->reading_state == MEI_IDLE)
ab841160 OW	399	*offset = 0;
	400
	401
33d28c92	402	write_cb = mei_io_cb_init(cl, file);
ab841160	403	if (!write_cb) {
33d28c92 TW	404	dev_err(&dev->pdev->dev, "write cb allocation failed\n");
33d28c92 TW	405	rets = -ENOMEM;
4234a6de	406	goto out;
ab841160	407	}
33d28c92 TW	408	rets = mei_io_cb_alloc_req_buf(write_cb, length);
33d28c92 TW	409	if (rets)
4234a6de	410	goto out;
ab841160	411
75f0ee15	412	rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
d8b29efa AU	413	if (rets) {
	414	dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
	415	rets = -EFAULT;
4234a6de	416	goto out;
d8b29efa	417	}
ab841160	418
ab841160	419	if (cl == &dev->iamthif_cl) {
ab5c4a56	420	rets = mei_amthif_write(dev, write_cb);
ab841160	421
ab5c4a56 TW	422	if (rets) {
ab5c4a56 TW	423	dev_err(&dev->pdev->dev,
1a1aca42	424	"amthif write failed with status = %d\n", rets);
4234a6de	425	goto out;
ab841160 OW	426	}
ab841160 OW	427	mutex_unlock(&dev->device_lock);
75f0ee15	428	return length;
ab841160 OW	429	}
ab841160 OW	430
4234a6de	431	rets = mei_cl_write(cl, write_cb, false);
b0d0cf77	432	out:
ab841160	433	mutex_unlock(&dev->device_lock);
4234a6de TW	434	if (rets < 0)
4234a6de TW	435	mei_io_cb_free(write_cb);
ab841160 OW	436	return rets;
	437	}
	438
9f81abda TW	439	/**
	440	* mei_ioctl_connect_client - the connect to fw client IOCTL function
	441	*
	442	* @dev: the device structure
	443	* @data: IOCTL connect data, input and output parameters
	444	* @file: private data of the file object
	445	*
	446	* Locking: called under "dev->device_lock" lock
	447	*
	448	* returns 0 on success, <0 on failure.
	449	*/
	450	static int mei_ioctl_connect_client(struct file *file,
	451	struct mei_connect_client_data *data)
	452	{
	453	struct mei_device *dev;
	454	struct mei_client *client;
	455	struct mei_cl *cl;
	456	int i;
	457	int rets;
	458
	459	cl = file->private_data;
	460	if (WARN_ON(!cl \|\| !cl->dev))
	461	return -ENODEV;
	462
	463	dev = cl->dev;
	464
	465	if (dev->dev_state != MEI_DEV_ENABLED) {
	466	rets = -ENODEV;
	467	goto end;
	468	}
	469
	470	if (cl->state != MEI_FILE_INITIALIZING &&
	471	cl->state != MEI_FILE_DISCONNECTED) {
	472	rets = -EBUSY;
	473	goto end;
	474	}
	475
	476	/* find ME client we're trying to connect to */
	477	i = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
80fe6361 TW	478	if (i < 0 \|\| dev->me_clients[i].props.fixed_address) {
	479	dev_dbg(&dev->pdev->dev, "Cannot connect to FW Client UUID = %pUl\n",
	480	&data->in_client_uuid);
	481	rets = -ENODEV;
	482	goto end;
9f81abda TW	483	}
9f81abda TW	484
80fe6361 TW	485	cl->me_client_id = dev->me_clients[i].client_id;
	486	cl->state = MEI_FILE_CONNECTING;
	487
9f81abda TW	488	dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
	489	cl->me_client_id);
	490	dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
	491	dev->me_clients[i].props.protocol_version);
	492	dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
	493	dev->me_clients[i].props.max_msg_length);
	494
1a1aca42	495	/* if we're connecting to amthif client then we will use the
9f81abda TW	496	* existing connection
9f81abda TW	497	*/
1a1aca42	498	if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) {
9f81abda TW	499	dev_dbg(&dev->pdev->dev, "FW Client is amthi\n");
	500	if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
	501	rets = -ENODEV;
	502	goto end;
	503	}
	504	clear_bit(cl->host_client_id, dev->host_clients_map);
	505	mei_cl_unlink(cl);
	506
	507	kfree(cl);
	508	cl = NULL;
	509	file->private_data = &dev->iamthif_cl;
	510
	511	client = &data->out_client_properties;
	512	client->max_msg_length =
	513	dev->me_clients[i].props.max_msg_length;
	514	client->protocol_version =
	515	dev->me_clients[i].props.protocol_version;
	516	rets = dev->iamthif_cl.status;
	517
	518	goto end;
	519	}
	520
9f81abda TW	521
	522	/* prepare the output buffer */
	523	client = &data->out_client_properties;
	524	client->max_msg_length = dev->me_clients[i].props.max_msg_length;
	525	client->protocol_version = dev->me_clients[i].props.protocol_version;
	526	dev_dbg(&dev->pdev->dev, "Can connect?\n");
	527
	528
	529	rets = mei_cl_connect(cl, file);
	530
	531	end:
9f81abda TW	532	return rets;
	533	}
	534
ab841160 OW	535
	536	/**
	537	* mei_ioctl - the IOCTL function
	538	*
	539	* @file: pointer to file structure
	540	* @cmd: ioctl command
	541	* @data: pointer to mei message structure
	542	*
	543	* returns 0 on success , <0 on error
	544	*/
	545	static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
	546	{
	547	struct mei_device *dev;
	548	struct mei_cl *cl = file->private_data;
	549	struct mei_connect_client_data *connect_data = NULL;
	550	int rets;
	551
	552	if (cmd != IOCTL_MEI_CONNECT_CLIENT)
	553	return -EINVAL;
	554
	555	if (WARN_ON(!cl \|\| !cl->dev))
	556	return -ENODEV;
	557
	558	dev = cl->dev;
	559
	560	dev_dbg(&dev->pdev->dev, "IOCTL cmd = 0x%x", cmd);
	561
	562	mutex_lock(&dev->device_lock);
b210d750	563	if (dev->dev_state != MEI_DEV_ENABLED) {
ab841160 OW	564	rets = -ENODEV;
	565	goto out;
	566	}
	567
	568	dev_dbg(&dev->pdev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
	569
	570	connect_data = kzalloc(sizeof(struct mei_connect_client_data),
	571	GFP_KERNEL);
	572	if (!connect_data) {
	573	rets = -ENOMEM;
	574	goto out;
	575	}
	576	dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
	577	if (copy_from_user(connect_data, (char __user *)data,
	578	sizeof(struct mei_connect_client_data))) {
d8b29efa	579	dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
ab841160 OW	580	rets = -EFAULT;
	581	goto out;
	582	}
9f81abda	583
ab841160 OW	584	rets = mei_ioctl_connect_client(file, connect_data);
	585
	586	/* if all is ok, copying the data back to user. */
	587	if (rets)
	588	goto out;
	589
	590	dev_dbg(&dev->pdev->dev, "copy connect data to user\n");
	591	if (copy_to_user((char __user *)data, connect_data,
	592	sizeof(struct mei_connect_client_data))) {
	593	dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
	594	rets = -EFAULT;
	595	goto out;
	596	}
	597
	598	out:
	599	kfree(connect_data);
	600	mutex_unlock(&dev->device_lock);
	601	return rets;
	602	}
	603
	604	/**
	605	* mei_compat_ioctl - the compat IOCTL function
	606	*
	607	* @file: pointer to file structure
	608	* @cmd: ioctl command
	609	* @data: pointer to mei message structure
	610	*
	611	* returns 0 on success , <0 on error
	612	*/
	613	#ifdef CONFIG_COMPAT
	614	static long mei_compat_ioctl(struct file *file,
441ab50f	615	unsigned int cmd, unsigned long data)
ab841160 OW	616	{
	617	return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
	618	}
	619	#endif
	620
	621
	622	/**
	623	* mei_poll - the poll function
	624	*
	625	* @file: pointer to file structure
	626	* @wait: pointer to poll_table structure
	627	*
	628	* returns poll mask
	629	*/
	630	static unsigned int mei_poll(struct file file, poll_table wait)
	631	{
	632	struct mei_cl *cl = file->private_data;
	633	struct mei_device *dev;
	634	unsigned int mask = 0;
	635
	636	if (WARN_ON(!cl \|\| !cl->dev))
b950ac1d	637	return POLLERR;
ab841160 OW	638
	639	dev = cl->dev;
	640
	641	mutex_lock(&dev->device_lock);
	642
b950ac1d TW	643	if (!mei_cl_is_connected(cl)) {
b950ac1d TW	644	mask = POLLERR;
ab841160 OW	645	goto out;
	646	}
	647
	648	mutex_unlock(&dev->device_lock);
b950ac1d TW	649
	650
	651	if (cl == &dev->iamthif_cl)
	652	return mei_amthif_poll(dev, file, wait);
	653
ab841160	654	poll_wait(file, &cl->tx_wait, wait);
b950ac1d	655
ab841160	656	mutex_lock(&dev->device_lock);
b950ac1d TW	657
	658	if (!mei_cl_is_connected(cl)) {
	659	mask = POLLERR;
	660	goto out;
	661	}
	662
ab841160 OW	663	if (MEI_WRITE_COMPLETE == cl->writing_state)
	664	mask \|= (POLLIN \| POLLRDNORM);
	665
	666	out:
	667	mutex_unlock(&dev->device_lock);
	668	return mask;
	669	}
	670
5b881e3c OW	671	/*
	672	* file operations structure will be used for mei char device.
	673	*/
	674	static const struct file_operations mei_fops = {
	675	.owner = THIS_MODULE,
	676	.read = mei_read,
	677	.unlocked_ioctl = mei_ioctl,
	678	#ifdef CONFIG_COMPAT
	679	.compat_ioctl = mei_compat_ioctl,
	680	#endif
	681	.open = mei_open,
	682	.release = mei_release,
	683	.write = mei_write,
	684	.poll = mei_poll,
	685	.llseek = no_llseek
	686	};
	687
5b881e3c OW	688	/*
	689	* Misc Device Struct
	690	*/
	691	static struct miscdevice mei_misc_device = {
c38ea24e	692	.name = "mei",
5b881e3c OW	693	.fops = &mei_fops,
	694	.minor = MISC_DYNAMIC_MINOR,
	695	};
	696
30e53bb8 TW	697
30e53bb8 TW	698	int mei_register(struct mei_device *dev)
9a123f19	699	{
30e53bb8 TW	700	int ret;
	701	mei_misc_device.parent = &dev->pdev->dev;
	702	ret = misc_register(&mei_misc_device);
	703	if (ret)
	704	return ret;
	705
	706	if (mei_dbgfs_register(dev, mei_misc_device.name))
	707	dev_err(&dev->pdev->dev, "cannot register debugfs\n");
	708
	709	return 0;
5b881e3c	710	}
40e0b67b	711	EXPORT_SYMBOL_GPL(mei_register);
5b881e3c	712
30e53bb8	713	void mei_deregister(struct mei_device *dev)
5b881e3c	714	{
30e53bb8	715	mei_dbgfs_deregister(dev);
a44cab4a	716	misc_deregister(&mei_misc_device);
2703d4b2	717	mei_misc_device.parent = NULL;
5b881e3c	718	}
40e0b67b	719	EXPORT_SYMBOL_GPL(mei_deregister);
ab841160	720
cf3baefb SO	721	static int __init mei_init(void)
	722	{
	723	return mei_cl_bus_init();
	724	}
	725
	726	static void __exit mei_exit(void)
	727	{
	728	mei_cl_bus_exit();
	729	}
	730
	731	module_init(mei_init);
	732	module_exit(mei_exit);
	733
40e0b67b TW	734	MODULE_AUTHOR("Intel Corporation");
40e0b67b TW	735	MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
827eef51	736	MODULE_LICENSE("GPL v2");
ab841160	737