virtio: console: Move file back to drivers/char/

Commit 728674a7e466628df2aeec6d11a2ae1ef968fb67 moved virtio_console.c
to drivers/tty/hvc/ under the perception of this being an hvc driver.
It was such once, but these days it has generic communication
capabilities as well, so move it to drivers/char/.

In the future, the hvc part from this file can be split off and moved
under drivers/tty/hvc/.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 0 insertions, 1839 deletions

diff --git a/drivers/tty/hvc/Makefile b/drivers/tty/hvc/Makefile
index e6bed5f177f..d79e7e9bf9d 100644
--- a/drivers/tty/hvc/Makefile
+++ b/drivers/tty/hvc/Makefile
@@ -10,4 +10,3 @@ obj-$(CONFIG_HVC_XEN)		+= hvc_xen.o
 obj-$(CONFIG_HVC_IUCV)		+= hvc_iucv.o
 obj-$(CONFIG_HVC_UDBG)		+= hvc_udbg.o
 obj-$(CONFIG_HVCS)		+= hvcs.o
-obj-$(CONFIG_VIRTIO_CONSOLE)	+= virtio_console.o
diff --git a/drivers/tty/hvc/virtio_console.c b/drivers/tty/hvc/virtio_console.c
deleted file mode 100644
index 896a2ced1d2..00000000000
--- a/drivers/tty/hvc/virtio_console.c
+++ /dev/null
@@ -1,1838 +0,0 @@
-/*
- * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
- * Copyright (C) 2009, 2010 Red Hat, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- */
-#include <linux/cdev.h>
-#include <linux/debugfs.h>
-#include <linux/device.h>
-#include <linux/err.h>
-#include <linux/fs.h>
-#include <linux/init.h>
-#include <linux/list.h>
-#include <linux/poll.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/virtio.h>
-#include <linux/virtio_console.h>
-#include <linux/wait.h>
-#include <linux/workqueue.h>
-#include "hvc_console.h"
-
-/*
- * This is a global struct for storing common data for all the devices
- * this driver handles.
- *
- * Mainly, it has a linked list for all the consoles in one place so
- * that callbacks from hvc for get_chars(), put_chars() work properly
- * across multiple devices and multiple ports per device.
- */
-struct ports_driver_data {
-	/* Used for registering chardevs */
-	struct class *class;
-
-	/* Used for exporting per-port information to debugfs */
-	struct dentry *debugfs_dir;
-
-	/* List of all the devices we're handling */
-	struct list_head portdevs;
-
-	/* Number of devices this driver is handling */
-	unsigned int index;
-
-	/*
-	 * This is used to keep track of the number of hvc consoles
-	 * spawned by this driver.  This number is given as the first
-	 * argument to hvc_alloc().  To correctly map an initial
-	 * console spawned via hvc_instantiate to the console being
-	 * hooked up via hvc_alloc, we need to pass the same vtermno.
-	 *
-	 * We also just assume the first console being initialised was
-	 * the first one that got used as the initial console.
-	 */
-	unsigned int next_vtermno;
-
-	/* All the console devices handled by this driver */
-	struct list_head consoles;
-};
-static struct ports_driver_data pdrvdata;
-
-DEFINE_SPINLOCK(pdrvdata_lock);
-
-/* This struct holds information that's relevant only for console ports */
-struct console {
-	/* We'll place all consoles in a list in the pdrvdata struct */
-	struct list_head list;
-
-	/* The hvc device associated with this console port */
-	struct hvc_struct *hvc;
-
-	/* The size of the console */
-	struct winsize ws;
-
-	/*
-	 * This number identifies the number that we used to register
-	 * with hvc in hvc_instantiate() and hvc_alloc(); this is the
-	 * number passed on by the hvc callbacks to us to
-	 * differentiate between the other console ports handled by
-	 * this driver
-	 */
-	u32 vtermno;
-};
-
-struct port_buffer {
-	char *buf;
-
-	/* size of the buffer in *buf above */
-	size_t size;
-
-	/* used length of the buffer */
-	size_t len;
-	/* offset in the buf from which to consume data */
-	size_t offset;
-};
-
-/*
- * This is a per-device struct that stores data common to all the
- * ports for that device (vdev->priv).
- */
-struct ports_device {
-	/* Next portdev in the list, head is in the pdrvdata struct */
-	struct list_head list;
-
-	/*
-	 * Workqueue handlers where we process deferred work after
-	 * notification
-	 */
-	struct work_struct control_work;
-
-	struct list_head ports;
-
-	/* To protect the list of ports */
-	spinlock_t ports_lock;
-
-	/* To protect the vq operations for the control channel */
-	spinlock_t cvq_lock;
-
-	/* The current config space is stored here */
-	struct virtio_console_config config;
-
-	/* The virtio device we're associated with */
-	struct virtio_device *vdev;
-
-	/*
-	 * A couple of virtqueues for the control channel: one for
-	 * guest->host transfers, one for host->guest transfers
-	 */
-	struct virtqueue *c_ivq, *c_ovq;
-
-	/* Array of per-port IO virtqueues */
-	struct virtqueue **in_vqs, **out_vqs;
-
-	/* Used for numbering devices for sysfs and debugfs */
-	unsigned int drv_index;
-
-	/* Major number for this device.  Ports will be created as minors. */
-	int chr_major;
-};
-
-/* This struct holds the per-port data */
-struct port {
-	/* Next port in the list, head is in the ports_device */
-	struct list_head list;
-
-	/* Pointer to the parent virtio_console device */
-	struct ports_device *portdev;
-
-	/* The current buffer from which data has to be fed to readers */
-	struct port_buffer *inbuf;
-
-	/*
-	 * To protect the operations on the in_vq associated with this
-	 * port.  Has to be a spinlock because it can be called from
-	 * interrupt context (get_char()).
-	 */
-	spinlock_t inbuf_lock;
-
-	/* Protect the operations on the out_vq. */
-	spinlock_t outvq_lock;
-
-	/* The IO vqs for this port */
-	struct virtqueue *in_vq, *out_vq;
-
-	/* File in the debugfs directory that exposes this port's information */
-	struct dentry *debugfs_file;
-
-	/*
-	 * The entries in this struct will be valid if this port is
-	 * hooked up to an hvc console
-	 */
-	struct console cons;
-
-	/* Each port associates with a separate char device */
-	struct cdev *cdev;
-	struct device *dev;
-
-	/* Reference-counting to handle port hot-unplugs and file operations */
-	struct kref kref;
-
-	/* A waitqueue for poll() or blocking read operations */
-	wait_queue_head_t waitqueue;
-
-	/* The 'name' of the port that we expose via sysfs properties */
-	char *name;
-
-	/* We can notify apps of host connect / disconnect events via SIGIO */
-	struct fasync_struct *async_queue;
-
-	/* The 'id' to identify the port with the Host */
-	u32 id;
-
-	bool outvq_full;
-
-	/* Is the host device open */
-	bool host_connected;
-
-	/* We should allow only one process to open a port */
-	bool guest_connected;
-};
-
-/* This is the very early arch-specified put chars function. */
-static int (*early_put_chars)(u32, const char *, int);
-
-static struct port *find_port_by_vtermno(u32 vtermno)
-{
-	struct port *port;
-	struct console *cons;
-	unsigned long flags;
-
-	spin_lock_irqsave(&pdrvdata_lock, flags);
-	list_for_each_entry(cons, &pdrvdata.consoles, list) {
-		if (cons->vtermno == vtermno) {
-			port = container_of(cons, struct port, cons);
-			goto out;
-		}
-	}
-	port = NULL;
-out:
-	spin_unlock_irqrestore(&pdrvdata_lock, flags);
-	return port;
-}
-
-static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
-						 dev_t dev)
-{
-	struct port *port;
-	unsigned long flags;
-
-	spin_lock_irqsave(&portdev->ports_lock, flags);
-	list_for_each_entry(port, &portdev->ports, list)
-		if (port->cdev->dev == dev)
-			goto out;
-	port = NULL;
-out:
-	spin_unlock_irqrestore(&portdev->ports_lock, flags);
-
-	return port;
-}
-
-static struct port *find_port_by_devt(dev_t dev)
-{
-	struct ports_device *portdev;
-	struct port *port;
-	unsigned long flags;
-
-	spin_lock_irqsave(&pdrvdata_lock, flags);
-	list_for_each_entry(portdev, &pdrvdata.portdevs, list) {
-		port = find_port_by_devt_in_portdev(portdev, dev);
-		if (port)
-			goto out;
-	}
-	port = NULL;
-out:
-	spin_unlock_irqrestore(&pdrvdata_lock, flags);
-	return port;
-}
-
-static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
-{
-	struct port *port;
-	unsigned long flags;
-
-	spin_lock_irqsave(&portdev->ports_lock, flags);
-	list_for_each_entry(port, &portdev->ports, list)
-		if (port->id == id)
-			goto out;
-	port = NULL;
-out:
-	spin_unlock_irqrestore(&portdev->ports_lock, flags);
-
-	return port;
-}
-
-static struct port *find_port_by_vq(struct ports_device *portdev,
-				    struct virtqueue *vq)
-{
-	struct port *port;
-	unsigned long flags;
-
-	spin_lock_irqsave(&portdev->ports_lock, flags);
-	list_for_each_entry(port, &portdev->ports, list)
-		if (port->in_vq == vq || port->out_vq == vq)
-			goto out;
-	port = NULL;
-out:
-	spin_unlock_irqrestore(&portdev->ports_lock, flags);
-	return port;
-}
-
-static bool is_console_port(struct port *port)
-{
-	if (port->cons.hvc)
-		return true;
-	return false;
-}
-
-static inline bool use_multiport(struct ports_device *portdev)
-{
-	/*
-	 * This condition can be true when put_chars is called from
-	 * early_init
-	 */
-	if (!portdev->vdev)
-		return 0;
-	return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
-}
-
-static void free_buf(struct port_buffer *buf)
-{
-	kfree(buf->buf);
-	kfree(buf);
-}
-
-static struct port_buffer *alloc_buf(size_t buf_size)
-{
-	struct port_buffer *buf;
-
-	buf = kmalloc(sizeof(*buf), GFP_KERNEL);
-	if (!buf)
-		goto fail;
-	buf->buf = kzalloc(buf_size, GFP_KERNEL);
-	if (!buf->buf)
-		goto free_buf;
-	buf->len = 0;
-	buf->offset = 0;
-	buf->size = buf_size;
-	return buf;
-
-free_buf:
-	kfree(buf);
-fail:
-	return NULL;
-}
-
-/* Callers should take appropriate locks */
-static void *get_inbuf(struct port *port)
-{
-	struct port_buffer *buf;
-	struct virtqueue *vq;
-	unsigned int len;
-
-	vq = port->in_vq;
-	buf = virtqueue_get_buf(vq, &len);
-	if (buf) {
-		buf->len = len;
-		buf->offset = 0;
-	}
-	return buf;
-}
-
-/*
- * Create a scatter-gather list representing our input buffer and put
- * it in the queue.
- *
- * Callers should take appropriate locks.
- */
-static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
-{
-	struct scatterlist sg[1];
-	int ret;
-
-	sg_init_one(sg, buf->buf, buf->size);
-
-	ret = virtqueue_add_buf(vq, sg, 0, 1, buf);
-	virtqueue_kick(vq);
-	return ret;
-}
-
-/* Discard any unread data this port has. Callers lockers. */
-static void discard_port_data(struct port *port)
-{
-	struct port_buffer *buf;
-	struct virtqueue *vq;
-	unsigned int len;
-	int ret;
-
-	vq = port->in_vq;
-	if (port->inbuf)
-		buf = port->inbuf;
-	else
-		buf = virtqueue_get_buf(vq, &len);
-
-	ret = 0;
-	while (buf) {
-		if (add_inbuf(vq, buf) < 0) {
-			ret++;
-			free_buf(buf);
-		}
-		buf = virtqueue_get_buf(vq, &len);
-	}
-	port->inbuf = NULL;
-	if (ret)
-		dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
-			 ret);
-}
-
-static bool port_has_data(struct port *port)
-{
-	unsigned long flags;
-	bool ret;
-
-	spin_lock_irqsave(&port->inbuf_lock, flags);
-	if (port->inbuf) {
-		ret = true;
-		goto out;
-	}
-	port->inbuf = get_inbuf(port);
-	if (port->inbuf) {
-		ret = true;
-		goto out;
-	}
-	ret = false;
-out:
-	spin_unlock_irqrestore(&port->inbuf_lock, flags);
-	return ret;
-}
-
-static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
-				  unsigned int event, unsigned int value)
-{
-	struct scatterlist sg[1];
-	struct virtio_console_control cpkt;
-	struct virtqueue *vq;
-	unsigned int len;
-
-	if (!use_multiport(portdev))
-		return 0;
-
-	cpkt.id = port_id;
-	cpkt.event = event;
-	cpkt.value = value;
-
-	vq = portdev->c_ovq;
-
-	sg_init_one(sg, &cpkt, sizeof(cpkt));
-	if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
-		virtqueue_kick(vq);
-		while (!virtqueue_get_buf(vq, &len))
-			cpu_relax();
-	}
-	return 0;
-}
-
-static ssize_t send_control_msg(struct port *port, unsigned int event,
-				unsigned int value)
-{
-	/* Did the port get unplugged before userspace closed it? */
-	if (port->portdev)
-		return __send_control_msg(port->portdev, port->id, event, value);
-	return 0;
-}
-
-/* Callers must take the port->outvq_lock */
-static void reclaim_consumed_buffers(struct port *port)
-{
-	void *buf;
-	unsigned int len;
-
-	while ((buf = virtqueue_get_buf(port->out_vq, &len))) {
-		kfree(buf);
-		port->outvq_full = false;
-	}
-}
-
-static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
-			bool nonblock)
-{
-	struct scatterlist sg[1];
-	struct virtqueue *out_vq;
-	ssize_t ret;
-	unsigned long flags;
-	unsigned int len;
-
-	out_vq = port->out_vq;
-
-	spin_lock_irqsave(&port->outvq_lock, flags);
-
-	reclaim_consumed_buffers(port);
-
-	sg_init_one(sg, in_buf, in_count);
-	ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf);
-
-	/* Tell Host to go! */
-	virtqueue_kick(out_vq);
-
-	if (ret < 0) {
-		in_count = 0;
-		goto done;
-	}
-
-	if (ret == 0)
-		port->outvq_full = true;
-
-	if (nonblock)
-		goto done;
-
-	/*
-	 * Wait till the host acknowledges it pushed out the data we
-	 * sent.  This is done for data from the hvc_console; the tty
-	 * operations are performed with spinlocks held so we can't
-	 * sleep here.  An alternative would be to copy the data to a
-	 * buffer and relax the spinning requirement.  The downside is
-	 * we need to kmalloc a GFP_ATOMIC buffer each time the
-	 * console driver writes something out.
-	 */
-	while (!virtqueue_get_buf(out_vq, &len))
-		cpu_relax();
-done:
-	spin_unlock_irqrestore(&port->outvq_lock, flags);
-	/*
-	 * We're expected to return the amount of data we wrote -- all
-	 * of it
-	 */
-	return in_count;
-}
-
-/*
- * Give out the data that's requested from the buffer that we have
- * queued up.
- */
-static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
-			    bool to_user)
-{
-	struct port_buffer *buf;
-	unsigned long flags;
-
-	if (!out_count || !port_has_data(port))
-		return 0;
-
-	buf = port->inbuf;
-	out_count = min(out_count, buf->len - buf->offset);
-
-	if (to_user) {
-		ssize_t ret;
-
-		ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
-		if (ret)
-			return -EFAULT;
-	} else {
-		memcpy(out_buf, buf->buf + buf->offset, out_count);
-	}
-
-	buf->offset += out_count;
-
-	if (buf->offset == buf->len) {
-		/*
-		 * We're done using all the data in this buffer.
-		 * Re-queue so that the Host can send us more data.
-		 */
-		spin_lock_irqsave(&port->inbuf_lock, flags);
-		port->inbuf = NULL;
-
-		if (add_inbuf(port->in_vq, buf) < 0)
-			dev_warn(port->dev, "failed add_buf\n");
-
-		spin_unlock_irqrestore(&port->inbuf_lock, flags);
-	}
-	/* Return the number of bytes actually copied */
-	return out_count;
-}
-
-/* The condition that must be true for polling to end */
-static bool will_read_block(struct port *port)
-{
-	if (!port->guest_connected) {
-		/* Port got hot-unplugged. Let's exit. */
-		return false;
-	}
-	return !port_has_data(port) && port->host_connected;
-}
-
-static bool will_write_block(struct port *port)
-{
-	bool ret;
-
-	if (!port->guest_connected) {
-		/* Port got hot-unplugged. Let's exit. */
-		return false;
-	}
-	if (!port->host_connected)
-		return true;
-
-	spin_lock_irq(&port->outvq_lock);
-	/*
-	 * Check if the Host has consumed any buffers since we last
-	 * sent data (this is only applicable for nonblocking ports).
-	 */
-	reclaim_consumed_buffers(port);
-	ret = port->outvq_full;
-	spin_unlock_irq(&port->outvq_lock);
-
-	return ret;
-}
-
-static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
-			      size_t count, loff_t *offp)
-{
-	struct port *port;
-	ssize_t ret;
-
-	port = filp->private_data;
-
-	if (!port_has_data(port)) {
-		/*
-		 * If nothing's connected on the host just return 0 in
-		 * case of list_empty; this tells the userspace app
-		 * that there's no connection
-		 */
-		if (!port->host_connected)
-			return 0;
-		if (filp->f_flags & O_NONBLOCK)
-			return -EAGAIN;
-
-		ret = wait_event_interruptible(port->waitqueue,
-					       !will_read_block(port));
-		if (ret < 0)
-			return ret;
-	}
-	/* Port got hot-unplugged. */
-	if (!port->guest_connected)
-		return -ENODEV;
-	/*
-	 * We could've received a disconnection message while we were
-	 * waiting for more data.
-	 *
-	 * This check is not clubbed in the if() statement above as we
-	 * might receive some data as well as the host could get
-	 * disconnected after we got woken up from our wait.  So we
-	 * really want to give off whatever data we have and only then
-	 * check for host_connected.
-	 */
-	if (!port_has_data(port) && !port->host_connected)
-		return 0;
-
-	return fill_readbuf(port, ubuf, count, true);
-}
-
-static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
-			       size_t count, loff_t *offp)
-{
-	struct port *port;
-	char *buf;
-	ssize_t ret;
-	bool nonblock;
-
-	/* Userspace could be out to fool us */
-	if (!count)
-		return 0;
-
-	port = filp->private_data;
-
-	nonblock = filp->f_flags & O_NONBLOCK;
-
-	if (will_write_block(port)) {
-		if (nonblock)
-			return -EAGAIN;
-
-		ret = wait_event_interruptible(port->waitqueue,
-					       !will_write_block(port));
-		if (ret < 0)
-			return ret;
-	}
-	/* Port got hot-unplugged. */
-	if (!port->guest_connected)
-		return -ENODEV;
-
-	count = min((size_t)(32 * 1024), count);
-
-	buf = kmalloc(count, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	ret = copy_from_user(buf, ubuf, count);
-	if (ret) {
-		ret = -EFAULT;
-		goto free_buf;
-	}
-
-	/*
-	 * We now ask send_buf() to not spin for generic ports -- we
-	 * can re-use the same code path that non-blocking file
-	 * descriptors take for blocking file descriptors since the
-	 * wait is already done and we're certain the write will go
-	 * through to the host.
-	 */
-	nonblock = true;
-	ret = send_buf(port, buf, count, nonblock);
-
-	if (nonblock && ret > 0)
-		goto out;
-
-free_buf:
-	kfree(buf);
-out:
-	return ret;
-}
-
-static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
-{
-	struct port *port;
-	unsigned int ret;
-
-	port = filp->private_data;
-	poll_wait(filp, &port->waitqueue, wait);
-
-	if (!port->guest_connected) {
-		/* Port got unplugged */
-		return POLLHUP;
-	}
-	ret = 0;
-	if (!will_read_block(port))
-		ret |= POLLIN | POLLRDNORM;
-	if (!will_write_block(port))
-		ret |= POLLOUT;
-	if (!port->host_connected)
-		ret |= POLLHUP;
-
-	return ret;
-}
-
-static void remove_port(struct kref *kref);
-
-static int port_fops_release(struct inode *inode, struct file *filp)
-{
-	struct port *port;
-
-	port = filp->private_data;
-
-	/* Notify host of port being closed */
-	send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
-
-	spin_lock_irq(&port->inbuf_lock);
-	port->guest_connected = false;
-
-	discard_port_data(port);
-
-	spin_unlock_irq(&port->inbuf_lock);
-
-	spin_lock_irq(&port->outvq_lock);
-	reclaim_consumed_buffers(port);
-	spin_unlock_irq(&port->outvq_lock);
-
-	/*
-	 * Locks aren't necessary here as a port can't be opened after
-	 * unplug, and if a port isn't unplugged, a kref would already
-	 * exist for the port.  Plus, taking ports_lock here would
-	 * create a dependency on other locks taken by functions
-	 * inside remove_port if we're the last holder of the port,
-	 * creating many problems.
-	 */
-	kref_put(&port->kref, remove_port);
-
-	return 0;
-}
-
-static int port_fops_open(struct inode *inode, struct file *filp)
-{
-	struct cdev *cdev = inode->i_cdev;
-	struct port *port;
-	int ret;
-
-	port = find_port_by_devt(cdev->dev);
-	filp->private_data = port;
-
-	/* Prevent against a port getting hot-unplugged at the same time */
-	spin_lock_irq(&port->portdev->ports_lock);
-	kref_get(&port->kref);
-	spin_unlock_irq(&port->portdev->ports_lock);
-
-	/*
-	 * Don't allow opening of console port devices -- that's done
-	 * via /dev/hvc
-	 */
-	if (is_console_port(port)) {
-		ret = -ENXIO;
-		goto out;
-	}
-
-	/* Allow only one process to open a particular port at a time */
-	spin_lock_irq(&port->inbuf_lock);
-	if (port->guest_connected) {
-		spin_unlock_irq(&port->inbuf_lock);
-		ret = -EMFILE;
-		goto out;
-	}
-
-	port->guest_connected = true;
-	spin_unlock_irq(&port->inbuf_lock);
-
-	spin_lock_irq(&port->outvq_lock);
-	/*
-	 * There might be a chance that we missed reclaiming a few
-	 * buffers in the window of the port getting previously closed
-	 * and opening now.
-	 */
-	reclaim_consumed_buffers(port);
-	spin_unlock_irq(&port->outvq_lock);
-
-	nonseekable_open(inode, filp);
-
-	/* Notify host of port being opened */
-	send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
-
-	return 0;
-out:
-	kref_put(&port->kref, remove_port);
-	return ret;
-}
-
-static int port_fops_fasync(int fd, struct file *filp, int mode)
-{
-	struct port *port;
-
-	port = filp->private_data;
-	return fasync_helper(fd, filp, mode, &port->async_queue);
-}
-
-/*
- * The file operations that we support: programs in the guest can open
- * a console device, read from it, write to it, poll for data and
- * close it.  The devices are at
- *   /dev/vport<device number>p<port number>
- */
-static const struct file_operations port_fops = {
-	.owner = THIS_MODULE,
-	.open  = port_fops_open,
-	.read  = port_fops_read,
-	.write = port_fops_write,
-	.poll  = port_fops_poll,
-	.release = port_fops_release,
-	.fasync = port_fops_fasync,
-	.llseek = no_llseek,
-};
-
-/*
- * The put_chars() callback is pretty straightforward.
- *
- * We turn the characters into a scatter-gather list, add it to the
- * output queue and then kick the Host.  Then we sit here waiting for
- * it to finish: inefficient in theory, but in practice
- * implementations will do it immediately (lguest's Launcher does).
- */
-static int put_chars(u32 vtermno, const char *buf, int count)
-{
-	struct port *port;
-
-	if (unlikely(early_put_chars))
-		return early_put_chars(vtermno, buf, count);
-
-	port = find_port_by_vtermno(vtermno);
-	if (!port)
-		return -EPIPE;
-
-	return send_buf(port, (void *)buf, count, false);
-}
-
-/*
- * get_chars() is the callback from the hvc_console infrastructure
- * when an interrupt is received.
- *
- * We call out to fill_readbuf that gets us the required data from the
- * buffers that are queued up.
- */
-static int get_chars(u32 vtermno, char *buf, int count)
-{
-	struct port *port;
-
-	/* If we've not set up the port yet, we have no input to give. */
-	if (unlikely(early_put_chars))
-		return 0;
-
-	port = find_port_by_vtermno(vtermno);
-	if (!port)
-		return -EPIPE;
-
-	/* If we don't have an input queue yet, we can't get input. */
-	BUG_ON(!port->in_vq);
-
-	return fill_readbuf(port, buf, count, false);
-}
-
-static void resize_console(struct port *port)
-{
-	struct virtio_device *vdev;
-
-	/* The port could have been hot-unplugged */
-	if (!port || !is_console_port(port))
-		return;
-
-	vdev = port->portdev->vdev;
-	if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
-		hvc_resize(port->cons.hvc, port->cons.ws);
-}
-
-/* We set the configuration at this point, since we now have a tty */
-static int notifier_add_vio(struct hvc_struct *hp, int data)
-{
-	struct port *port;
-
-	port = find_port_by_vtermno(hp->vtermno);
-	if (!port)
-		return -EINVAL;
-
-	hp->irq_requested = 1;
-	resize_console(port);
-
-	return 0;
-}
-
-static void notifier_del_vio(struct hvc_struct *hp, int data)
-{
-	hp->irq_requested = 0;
-}
-
-/* The operations for console ports. */
-static const struct hv_ops hv_ops = {
-	.get_chars = get_chars,
-	.put_chars = put_chars,
-	.notifier_add = notifier_add_vio,
-	.notifier_del = notifier_del_vio,
-	.notifier_hangup = notifier_del_vio,
-};
-
-/*
- * Console drivers are initialized very early so boot messages can go
- * out, so we do things slightly differently from the generic virtio
- * initialization of the net and block drivers.
- *
- * At this stage, the console is output-only.  It's too early to set
- * up a virtqueue, so we let the drivers do some boutique early-output
- * thing.
- */
-int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
-{
-	early_put_chars = put_chars;
-	return hvc_instantiate(0, 0, &hv_ops);
-}
-
-int init_port_console(struct port *port)
-{
-	int ret;
-
-	/*
-	 * The Host's telling us this port is a console port.  Hook it
-	 * up with an hvc console.
-	 *
-	 * To set up and manage our virtual console, we call
-	 * hvc_alloc().
-	 *
-	 * The first argument of hvc_alloc() is the virtual console
-	 * number.  The second argument is the parameter for the
-	 * notification mechanism (like irq number).  We currently
-	 * leave this as zero, virtqueues have implicit notifications.
-	 *
-	 * The third argument is a "struct hv_ops" containing the
-	 * put_chars() get_chars(), notifier_add() and notifier_del()
-	 * pointers.  The final argument is the output buffer size: we
-	 * can do any size, so we put PAGE_SIZE here.
-	 */
-	port->cons.vtermno = pdrvdata.next_vtermno;
-
-	port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
-	if (IS_ERR(port->cons.hvc)) {
-		ret = PTR_ERR(port->cons.hvc);
-		dev_err(port->dev,
-			"error %d allocating hvc for port\n", ret);
-		port->cons.hvc = NULL;
-		return ret;
-	}
-	spin_lock_irq(&pdrvdata_lock);
-	pdrvdata.next_vtermno++;
-	list_add_tail(&port->cons.list, &pdrvdata.consoles);
-	spin_unlock_irq(&pdrvdata_lock);
-	port->guest_connected = true;
-
-	/*
-	 * Start using the new console output if this is the first
-	 * console to come up.
-	 */
-	if (early_put_chars)
-		early_put_chars = NULL;
-
-	/* Notify host of port being opened */
-	send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
-
-	return 0;
-}
-
-static ssize_t show_port_name(struct device *dev,
-			      struct device_attribute *attr, char *buffer)
-{
-	struct port *port;
-
-	port = dev_get_drvdata(dev);
-
-	return sprintf(buffer, "%s\n", port->name);
-}
-
-static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
-
-static struct attribute *port_sysfs_entries[] = {
-	&dev_attr_name.attr,
-	NULL
-};
-
-static struct attribute_group port_attribute_group = {
-	.name = NULL,		/* put in device directory */
-	.attrs = port_sysfs_entries,
-};
-
-static int debugfs_open(struct inode *inode, struct file *filp)
-{
-	filp->private_data = inode->i_private;
-	return 0;
-}
-
-static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
-			    size_t count, loff_t *offp)
-{
-	struct port *port;
-	char *buf;
-	ssize_t ret, out_offset, out_count;
-
-	out_count = 1024;
-	buf = kmalloc(out_count, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	port = filp->private_data;
-	out_offset = 0;
-	out_offset += snprintf(buf + out_offset, out_count,
-			       "name: %s\n", port->name ? port->name : "");
-	out_offset += snprintf(buf + out_offset, out_count - out_offset,
-			       "guest_connected: %d\n", port->guest_connected);
-	out_offset += snprintf(buf + out_offset, out_count - out_offset,
-			       "host_connected: %d\n", port->host_connected);
-	out_offset += snprintf(buf + out_offset, out_count - out_offset,
-			       "outvq_full: %d\n", port->outvq_full);
-	out_offset += snprintf(buf + out_offset, out_count - out_offset,
-			       "is_console: %s\n",
-			       is_console_port(port) ? "yes" : "no");
-	out_offset += snprintf(buf + out_offset, out_count - out_offset,
-			       "console_vtermno: %u\n", port->cons.vtermno);
-
-	ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
-	kfree(buf);
-	return ret;
-}
-
-static const struct file_operations port_debugfs_ops = {
-	.owner = THIS_MODULE,
-	.open  = debugfs_open,
-	.read  = debugfs_read,
-};
-
-static void set_console_size(struct port *port, u16 rows, u16 cols)
-{
-	if (!port || !is_console_port(port))
-		return;
-
-	port->cons.ws.ws_row = rows;
-	port->cons.ws.ws_col = cols;
-}
-
-static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
-{
-	struct port_buffer *buf;
-	unsigned int nr_added_bufs;
-	int ret;
-
-	nr_added_bufs = 0;
-	do {
-		buf = alloc_buf(PAGE_SIZE);
-		if (!buf)
-			break;
-
-		spin_lock_irq(lock);
-		ret = add_inbuf(vq, buf);
-		if (ret < 0) {
-			spin_unlock_irq(lock);
-			free_buf(buf);
-			break;
-		}
-		nr_added_bufs++;
-		spin_unlock_irq(lock);
-	} while (ret > 0);
-
-	return nr_added_bufs;
-}
-
-static void send_sigio_to_port(struct port *port)
-{
-	if (port->async_queue && port->guest_connected)
-		kill_fasync(&port->async_queue, SIGIO, POLL_OUT);
-}
-
-static int add_port(struct ports_device *portdev, u32 id)
-{
-	char debugfs_name[16];
-	struct port *port;
-	struct port_buffer *buf;
-	dev_t devt;
-	unsigned int nr_added_bufs;
-	int err;
-
-	port = kmalloc(sizeof(*port), GFP_KERNEL);
-	if (!port) {
-		err = -ENOMEM;
-		goto fail;
-	}
-	kref_init(&port->kref);
-
-	port->portdev = portdev;
-	port->id = id;
-
-	port->name = NULL;
-	port->inbuf = NULL;
-	port->cons.hvc = NULL;
-	port->async_queue = NULL;
-
-	port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
-
-	port->host_connected = port->guest_connected = false;
-
-	port->outvq_full = false;
-
-	port->in_vq = portdev->in_vqs[port->id];
-	port->out_vq = portdev->out_vqs[port->id];
-
-	port->cdev = cdev_alloc();
-	if (!port->cdev) {
-		dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n");
-		err = -ENOMEM;
-		goto free_port;
-	}
-	port->cdev->ops = &port_fops;
-
-	devt = MKDEV(portdev->chr_major, id);
-	err = cdev_add(port->cdev, devt, 1);
-	if (err < 0) {
-		dev_err(&port->portdev->vdev->dev,
-			"Error %d adding cdev for port %u\n", err, id);
-		goto free_cdev;
-	}
-	port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
-				  devt, port, "vport%up%u",
-				  port->portdev->drv_index, id);
-	if (IS_ERR(port->dev)) {
-		err = PTR_ERR(port->dev);
-		dev_err(&port->portdev->vdev->dev,
-			"Error %d creating device for port %u\n",
-			err, id);
-		goto free_cdev;
-	}
-
-	spin_lock_init(&port->inbuf_lock);
-	spin_lock_init(&port->outvq_lock);
-	init_waitqueue_head(&port->waitqueue);
-
-	/* Fill the in_vq with buffers so the host can send us data. */
-	nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
-	if (!nr_added_bufs) {
-		dev_err(port->dev, "Error allocating inbufs\n");
-		err = -ENOMEM;
-		goto free_device;
-	}
-
-	/*
-	 * If we're not using multiport support, this has to be a console port
-	 */
-	if (!use_multiport(port->portdev)) {
-		err = init_port_console(port);
-		if (err)
-			goto free_inbufs;
-	}
-
-	spin_lock_irq(&portdev->ports_lock);
-	list_add_tail(&port-&g