[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;

	if (cb) {
		mei_io_cb_free(cb);
		cb = 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
 *
 * 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 (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 > dev->me_clients[id].props.max_msg_length || length <= 0) {
		rets = -EMSGSIZE;
		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)
		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_dbg(&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
a562d5c2 TW	168	if (cb) {
a562d5c2 TW	169	mei_io_cb_free(cb);
ab841160	170	cb = NULL;
ab841160	171	}
a562d5c2 TW	172
	173	kfree(cl);
	174	out:
ab841160 OW	175	mutex_unlock(&dev->device_lock);
	176	return rets;
	177	}
	178
	179
	180	/**
	181	* mei_read - the read function.
	182	*
	183	* @file: pointer to file structure
	184	* @ubuf: pointer to user buffer
	185	* @length: buffer length
	186	* @offset: data offset in buffer
	187	*
	188	* returns >=0 data length on success , <0 on error
	189	*/
	190	static ssize_t mei_read(struct file file, char __user ubuf,
441ab50f	191	size_t length, loff_t *offset)
ab841160 OW	192	{
	193	struct mei_cl *cl = file->private_data;
	194	struct mei_cl_cb *cb_pos = NULL;
	195	struct mei_cl_cb *cb = NULL;
	196	struct mei_device *dev;
ab841160 OW	197	int rets;
	198	int err;
	199
	200
	201	if (WARN_ON(!cl \|\| !cl->dev))
	202	return -ENODEV;
	203
	204	dev = cl->dev;
	205
	206	mutex_lock(&dev->device_lock);
b210d750	207	if (dev->dev_state != MEI_DEV_ENABLED) {
ab841160 OW	208	rets = -ENODEV;
	209	goto out;
	210	}
	211
ab841160	212	if (cl == &dev->iamthif_cl) {
19838fb8	213	rets = mei_amthif_read(dev, file, ubuf, length, offset);
ab841160 OW	214	goto out;
	215	}
	216
139aacf7	217	if (cl->read_cb) {
ab841160	218	cb = cl->read_cb;
139aacf7 TW	219	/* read what left */
	220	if (cb->buf_idx > *offset)
	221	goto copy_buffer;
	222	/* offset is beyond buf_idx we have no more data return 0 */
	223	if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
	224	rets = 0;
	225	goto free;
	226	}
	227	/* Offset needs to be cleaned for contiguous reads*/
	228	if (cb->buf_idx == 0 && *offset > 0)
	229	*offset = 0;
	230	} else if (*offset > 0) {
ab841160	231	*offset = 0;
ab841160 OW	232	}
ab841160 OW	233
fcb136e1	234	err = mei_cl_read_start(cl, length);
ab841160 OW	235	if (err && err != -EBUSY) {
	236	dev_dbg(&dev->pdev->dev,
	237	"mei start read failure with status = %d\n", err);
	238	rets = err;
	239	goto out;
	240	}
	241
	242	if (MEI_READ_COMPLETE != cl->reading_state &&
	243	!waitqueue_active(&cl->rx_wait)) {
	244	if (file->f_flags & O_NONBLOCK) {
	245	rets = -EAGAIN;
	246	goto out;
	247	}
	248
	249	mutex_unlock(&dev->device_lock);
	250
	251	if (wait_event_interruptible(cl->rx_wait,
e2b31644 TW	252	MEI_READ_COMPLETE == cl->reading_state \|\|
	253	mei_cl_is_transitioning(cl))) {
	254
ab841160 OW	255	if (signal_pending(current))
	256	return -EINTR;
	257	return -ERESTARTSYS;
	258	}
	259
	260	mutex_lock(&dev->device_lock);
e2b31644	261	if (mei_cl_is_transitioning(cl)) {
ab841160 OW	262	rets = -EBUSY;
	263	goto out;
	264	}
	265	}
	266
	267	cb = cl->read_cb;
	268
	269	if (!cb) {
	270	rets = -ENODEV;
	271	goto out;
	272	}
	273	if (cl->reading_state != MEI_READ_COMPLETE) {
	274	rets = 0;
	275	goto out;
	276	}
	277	/* now copy the data to user space */
	278	copy_buffer:
fcb136e1 TW	279	dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
fcb136e1 TW	280	cb->response_buffer.size, cb->buf_idx);
ebb108ef	281	if (length == 0 \|\| ubuf == NULL \|\| *offset > cb->buf_idx) {
ab841160 OW	282	rets = -EMSGSIZE;
	283	goto free;
	284	}
	285
ebb108ef TW	286	/* length is being truncated to PAGE_SIZE,
	287	* however buf_idx may point beyond that */
	288	length = min_t(size_t, length, cb->buf_idx - *offset);
ab841160	289
441ab50f	290	if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
ab841160 OW	291	rets = -EFAULT;
	292	goto free;
	293	}
	294
	295	rets = length;
	296	*offset += length;
ebb108ef	297	if ((unsigned long)*offset < cb->buf_idx)
ab841160 OW	298	goto out;
	299
	300	free:
90e0b5f1	301	cb_pos = mei_cl_find_read_cb(cl);
ab841160 OW	302	/* Remove entry from read list */
ab841160 OW	303	if (cb_pos)
fb601adb	304	list_del(&cb_pos->list);
601a1efa	305	mei_io_cb_free(cb);
ab841160 OW	306	cl->reading_state = MEI_IDLE;
ab841160 OW	307	cl->read_cb = NULL;
ab841160 OW	308	out:
	309	dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
	310	mutex_unlock(&dev->device_lock);
	311	return rets;
	312	}
ab841160 OW	313	/**
	314	* mei_write - the write function.
	315	*
	316	* @file: pointer to file structure
	317	* @ubuf: pointer to user buffer
	318	* @length: buffer length
	319	* @offset: data offset in buffer
	320	*
	321	* returns >=0 data length on success , <0 on error
	322	*/
	323	static ssize_t mei_write(struct file file, const char __user ubuf,
441ab50f	324	size_t length, loff_t *offset)
ab841160 OW	325	{
	326	struct mei_cl *cl = file->private_data;
	327	struct mei_cl_cb *write_cb = NULL;
ab841160 OW	328	struct mei_device *dev;
	329	unsigned long timeout = 0;
	330	int rets;
4234a6de	331	int id;
ab841160 OW	332
	333	if (WARN_ON(!cl \|\| !cl->dev))
	334	return -ENODEV;
	335
	336	dev = cl->dev;
	337
	338	mutex_lock(&dev->device_lock);
	339
b210d750	340	if (dev->dev_state != MEI_DEV_ENABLED) {
75f0ee15	341	rets = -ENODEV;
4234a6de	342	goto out;
ab841160 OW	343	}
ab841160 OW	344
4234a6de TW	345	id = mei_me_cl_by_id(dev, cl->me_client_id);
4234a6de TW	346	if (id < 0) {
75f0ee15	347	rets = -ENODEV;
4234a6de	348	goto out;
75f0ee15	349	}
4234a6de	350	if (length > dev->me_clients[id].props.max_msg_length \|\| length <= 0) {
75f0ee15	351	rets = -EMSGSIZE;
4234a6de	352	goto out;
75f0ee15 TW	353	}
	354
	355	if (cl->state != MEI_FILE_CONNECTED) {
75f0ee15 TW	356	dev_err(&dev->pdev->dev, "host client = %d, is not connected to ME client = %d",
75f0ee15 TW	357	cl->host_client_id, cl->me_client_id);
4234a6de TW	358	rets = -ENODEV;
4234a6de TW	359	goto out;
75f0ee15	360	}
ab841160	361	if (cl == &dev->iamthif_cl) {
19838fb8	362	write_cb = mei_amthif_find_read_list_entry(dev, file);
ab841160 OW	363
	364	if (write_cb) {
	365	timeout = write_cb->read_time +
3870c320	366	mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
ab841160 OW	367
ab841160 OW	368	if (time_after(jiffies, timeout) \|\|
75f0ee15 TW	369	cl->reading_state == MEI_READ_COMPLETE) {
75f0ee15 TW	370	*offset = 0;
fb601adb	371	list_del(&write_cb->list);
601a1efa	372	mei_io_cb_free(write_cb);
75f0ee15	373	write_cb = NULL;
ab841160 OW	374	}
	375	}
	376	}
	377
	378	/* free entry used in read */
	379	if (cl->reading_state == MEI_READ_COMPLETE) {
	380	*offset = 0;
90e0b5f1	381	write_cb = mei_cl_find_read_cb(cl);
ab841160	382	if (write_cb) {
fb601adb	383	list_del(&write_cb->list);
601a1efa	384	mei_io_cb_free(write_cb);
ab841160 OW	385	write_cb = NULL;
	386	cl->reading_state = MEI_IDLE;
	387	cl->read_cb = NULL;
ab841160	388	}
d91aaed3	389	} else if (cl->reading_state == MEI_IDLE)
ab841160 OW	390	*offset = 0;
	391
	392
33d28c92	393	write_cb = mei_io_cb_init(cl, file);
ab841160	394	if (!write_cb) {
33d28c92 TW	395	dev_err(&dev->pdev->dev, "write cb allocation failed\n");
33d28c92 TW	396	rets = -ENOMEM;
4234a6de	397	goto out;
ab841160	398	}
33d28c92 TW	399	rets = mei_io_cb_alloc_req_buf(write_cb, length);
33d28c92 TW	400	if (rets)
4234a6de	401	goto out;
ab841160	402
75f0ee15 TW	403	rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
75f0ee15 TW	404	if (rets)
4234a6de	405	goto out;
ab841160	406
ab841160	407	if (cl == &dev->iamthif_cl) {
ab5c4a56	408	rets = mei_amthif_write(dev, write_cb);
ab841160	409
ab5c4a56 TW	410	if (rets) {
ab5c4a56 TW	411	dev_err(&dev->pdev->dev,
1a1aca42	412	"amthif write failed with status = %d\n", rets);
4234a6de	413	goto out;
ab841160 OW	414	}
ab841160 OW	415	mutex_unlock(&dev->device_lock);
75f0ee15	416	return length;
ab841160 OW	417	}
ab841160 OW	418
4234a6de	419	rets = mei_cl_write(cl, write_cb, false);
b0d0cf77	420	out:
ab841160	421	mutex_unlock(&dev->device_lock);
4234a6de TW	422	if (rets < 0)
4234a6de TW	423	mei_io_cb_free(write_cb);
ab841160 OW	424	return rets;
	425	}
	426
9f81abda TW	427	/**
	428	* mei_ioctl_connect_client - the connect to fw client IOCTL function
	429	*
	430	* @dev: the device structure
	431	* @data: IOCTL connect data, input and output parameters
	432	* @file: private data of the file object
	433	*
	434	* Locking: called under "dev->device_lock" lock
	435	*
	436	* returns 0 on success, <0 on failure.
	437	*/
	438	static int mei_ioctl_connect_client(struct file *file,
	439	struct mei_connect_client_data *data)
	440	{
	441	struct mei_device *dev;
	442	struct mei_client *client;
	443	struct mei_cl *cl;
	444	int i;
	445	int rets;
	446
	447	cl = file->private_data;
	448	if (WARN_ON(!cl \|\| !cl->dev))
	449	return -ENODEV;
	450
	451	dev = cl->dev;
	452
	453	if (dev->dev_state != MEI_DEV_ENABLED) {
	454	rets = -ENODEV;
	455	goto end;
	456	}
	457
	458	if (cl->state != MEI_FILE_INITIALIZING &&
	459	cl->state != MEI_FILE_DISCONNECTED) {
	460	rets = -EBUSY;
	461	goto end;
	462	}
	463
	464	/* find ME client we're trying to connect to */
	465	i = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
80fe6361 TW	466	if (i < 0 \|\| dev->me_clients[i].props.fixed_address) {
	467	dev_dbg(&dev->pdev->dev, "Cannot connect to FW Client UUID = %pUl\n",
	468	&data->in_client_uuid);
	469	rets = -ENODEV;
	470	goto end;
9f81abda TW	471	}
9f81abda TW	472
80fe6361 TW	473	cl->me_client_id = dev->me_clients[i].client_id;
	474	cl->state = MEI_FILE_CONNECTING;
	475
9f81abda TW	476	dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
	477	cl->me_client_id);
	478	dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
	479	dev->me_clients[i].props.protocol_version);
	480	dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
	481	dev->me_clients[i].props.max_msg_length);
	482
1a1aca42	483	/* if we're connecting to amthif client then we will use the
9f81abda TW	484	* existing connection
9f81abda TW	485	*/
1a1aca42	486	if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) {
9f81abda TW	487	dev_dbg(&dev->pdev->dev, "FW Client is amthi\n");
	488	if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
	489	rets = -ENODEV;
	490	goto end;
	491	}
	492	clear_bit(cl->host_client_id, dev->host_clients_map);
	493	mei_cl_unlink(cl);
	494
	495	kfree(cl);
	496	cl = NULL;
	497	file->private_data = &dev->iamthif_cl;
	498
	499	client = &data->out_client_properties;
	500	client->max_msg_length =
	501	dev->me_clients[i].props.max_msg_length;
	502	client->protocol_version =
	503	dev->me_clients[i].props.protocol_version;
	504	rets = dev->iamthif_cl.status;
	505
	506	goto end;
	507	}
	508
9f81abda TW	509
	510	/* prepare the output buffer */
	511	client = &data->out_client_properties;
	512	client->max_msg_length = dev->me_clients[i].props.max_msg_length;
	513	client->protocol_version = dev->me_clients[i].props.protocol_version;
	514	dev_dbg(&dev->pdev->dev, "Can connect?\n");
	515
	516
	517	rets = mei_cl_connect(cl, file);
	518
	519	end:
9f81abda TW	520	return rets;
	521	}
	522
ab841160 OW	523
	524	/**
	525	* mei_ioctl - the IOCTL function
	526	*
	527	* @file: pointer to file structure
	528	* @cmd: ioctl command
	529	* @data: pointer to mei message structure
	530	*
	531	* returns 0 on success , <0 on error
	532	*/
	533	static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
	534	{
	535	struct mei_device *dev;
	536	struct mei_cl *cl = file->private_data;
	537	struct mei_connect_client_data *connect_data = NULL;
	538	int rets;
	539
	540	if (cmd != IOCTL_MEI_CONNECT_CLIENT)
	541	return -EINVAL;
	542
	543	if (WARN_ON(!cl \|\| !cl->dev))
	544	return -ENODEV;
	545
	546	dev = cl->dev;
	547
	548	dev_dbg(&dev->pdev->dev, "IOCTL cmd = 0x%x", cmd);
	549
	550	mutex_lock(&dev->device_lock);
b210d750	551	if (dev->dev_state != MEI_DEV_ENABLED) {
ab841160 OW	552	rets = -ENODEV;
	553	goto out;
	554	}
	555
	556	dev_dbg(&dev->pdev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
	557
	558	connect_data = kzalloc(sizeof(struct mei_connect_client_data),
	559	GFP_KERNEL);
	560	if (!connect_data) {
	561	rets = -ENOMEM;
	562	goto out;
	563	}
	564	dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
	565	if (copy_from_user(connect_data, (char __user *)data,
	566	sizeof(struct mei_connect_client_data))) {
	567	dev_dbg(&dev->pdev->dev, "failed to copy data from userland\n");
	568	rets = -EFAULT;
	569	goto out;
	570	}
9f81abda	571
ab841160 OW	572	rets = mei_ioctl_connect_client(file, connect_data);
	573
	574	/* if all is ok, copying the data back to user. */
	575	if (rets)
	576	goto out;
	577
	578	dev_dbg(&dev->pdev->dev, "copy connect data to user\n");
	579	if (copy_to_user((char __user *)data, connect_data,
	580	sizeof(struct mei_connect_client_data))) {
	581	dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
	582	rets = -EFAULT;
	583	goto out;
	584	}
	585
	586	out:
	587	kfree(connect_data);
	588	mutex_unlock(&dev->device_lock);
	589	return rets;
	590	}
	591
	592	/**
	593	* mei_compat_ioctl - the compat IOCTL function
	594	*
	595	* @file: pointer to file structure
	596	* @cmd: ioctl command
	597	* @data: pointer to mei message structure
	598	*
	599	* returns 0 on success , <0 on error
	600	*/
	601	#ifdef CONFIG_COMPAT
	602	static long mei_compat_ioctl(struct file *file,
441ab50f	603	unsigned int cmd, unsigned long data)
ab841160 OW	604	{
	605	return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
	606	}
	607	#endif
	608
	609
	610	/**
	611	* mei_poll - the poll function
	612	*
	613	* @file: pointer to file structure
	614	* @wait: pointer to poll_table structure
	615	*
	616	* returns poll mask
	617	*/
	618	static unsigned int mei_poll(struct file file, poll_table wait)
	619	{
	620	struct mei_cl *cl = file->private_data;
	621	struct mei_device *dev;
	622	unsigned int mask = 0;
	623
	624	if (WARN_ON(!cl \|\| !cl->dev))
b950ac1d	625	return POLLERR;
ab841160 OW	626
	627	dev = cl->dev;
	628
	629	mutex_lock(&dev->device_lock);
	630
b950ac1d TW	631	if (!mei_cl_is_connected(cl)) {
b950ac1d TW	632	mask = POLLERR;
ab841160 OW	633	goto out;
	634	}
	635
	636	mutex_unlock(&dev->device_lock);
b950ac1d TW	637
	638
	639	if (cl == &dev->iamthif_cl)
	640	return mei_amthif_poll(dev, file, wait);
	641
ab841160	642	poll_wait(file, &cl->tx_wait, wait);
b950ac1d	643
ab841160	644	mutex_lock(&dev->device_lock);
b950ac1d TW	645
	646	if (!mei_cl_is_connected(cl)) {
	647	mask = POLLERR;
	648	goto out;
	649	}
	650
ab841160 OW	651	if (MEI_WRITE_COMPLETE == cl->writing_state)
	652	mask \|= (POLLIN \| POLLRDNORM);
	653
	654	out:
	655	mutex_unlock(&dev->device_lock);
	656	return mask;
	657	}
	658
5b881e3c OW	659	/*
	660	* file operations structure will be used for mei char device.
	661	*/
	662	static const struct file_operations mei_fops = {
	663	.owner = THIS_MODULE,
	664	.read = mei_read,
	665	.unlocked_ioctl = mei_ioctl,
	666	#ifdef CONFIG_COMPAT
	667	.compat_ioctl = mei_compat_ioctl,
	668	#endif
	669	.open = mei_open,
	670	.release = mei_release,
	671	.write = mei_write,
	672	.poll = mei_poll,
	673	.llseek = no_llseek
	674	};
	675
5b881e3c OW	676	/*
	677	* Misc Device Struct
	678	*/
	679	static struct miscdevice mei_misc_device = {
c38ea24e	680	.name = "mei",
5b881e3c OW	681	.fops = &mei_fops,
	682	.minor = MISC_DYNAMIC_MINOR,
	683	};
	684
30e53bb8 TW	685
30e53bb8 TW	686	int mei_register(struct mei_device *dev)
9a123f19	687	{
30e53bb8 TW	688	int ret;
	689	mei_misc_device.parent = &dev->pdev->dev;
	690	ret = misc_register(&mei_misc_device);
	691	if (ret)
	692	return ret;
	693
	694	if (mei_dbgfs_register(dev, mei_misc_device.name))
	695	dev_err(&dev->pdev->dev, "cannot register debugfs\n");
	696
	697	return 0;
5b881e3c	698	}
40e0b67b	699	EXPORT_SYMBOL_GPL(mei_register);
5b881e3c	700
30e53bb8	701	void mei_deregister(struct mei_device *dev)
5b881e3c	702	{
30e53bb8	703	mei_dbgfs_deregister(dev);
a44cab4a	704	misc_deregister(&mei_misc_device);
2703d4b2	705	mei_misc_device.parent = NULL;
5b881e3c	706	}
40e0b67b	707	EXPORT_SYMBOL_GPL(mei_deregister);
ab841160	708
cf3baefb SO	709	static int __init mei_init(void)
	710	{
	711	return mei_cl_bus_init();
	712	}
	713
	714	static void __exit mei_exit(void)
	715	{
	716	mei_cl_bus_exit();
	717	}
	718
	719	module_init(mei_init);
	720	module_exit(mei_exit);
	721
40e0b67b TW	722	MODULE_AUTHOR("Intel Corporation");
40e0b67b TW	723	MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
827eef51	724	MODULE_LICENSE("GPL v2");
ab841160	725