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authorAmit Shah <amit.shah@redhat.com>2011-02-01 09:31:25 +0530
committerGreg Kroah-Hartman <gregkh@suse.de>2011-02-03 14:43:12 -0800
commit51df0acc3d76cf41d5496ef044cc5717ab5c7f71 (patch)
tree414f9c3934d96213b0c092ad91f2c81469d84520 /drivers/tty
parentebf53826e105f488f4f628703a108e98940d1dc5 (diff)
downloadop-kernel-dev-51df0acc3d76cf41d5496ef044cc5717ab5c7f71.zip
op-kernel-dev-51df0acc3d76cf41d5496ef044cc5717ab5c7f71.tar.gz
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>
Diffstat (limited to 'drivers/tty')
-rw-r--r--drivers/tty/hvc/Makefile1
-rw-r--r--drivers/tty/hvc/virtio_console.c1838
2 files changed, 0 insertions, 1839 deletions
diff --git a/drivers/tty/hvc/Makefile b/drivers/tty/hvc/Makefile
index e6bed5f..d79e7e9 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 896a2ce..0000000
--- 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->list, &port->portdev->ports);
- spin_unlock_irq(&portdev->ports_lock);
-
- /*
- * Tell the Host we're set so that it can send us various
- * configuration parameters for this port (eg, port name,
- * caching, whether this is a console port, etc.)
- */
- send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
-
- if (pdrvdata.debugfs_dir) {
- /*
- * Finally, create the debugfs file that we can use to
- * inspect a port's state at any time
- */
- sprintf(debugfs_name, "vport%up%u",
- port->portdev->drv_index, id);
- port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
- pdrvdata.debugfs_dir,
- port,
- &port_debugfs_ops);
- }
- return 0;
-
-free_inbufs:
- while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
- free_buf(buf);
-free_device:
- device_destroy(pdrvdata.class, port->dev->devt);
-free_cdev:
- cdev_del(port->cdev);
-free_port:
- kfree(port);
-fail:
- /* The host might want to notify management sw about port add failure */
- __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
- return err;
-}
-
-/* No users remain, remove all port-specific data. */
-static void remove_port(struct kref *kref)
-{
- struct port *port;
-
- port = container_of(kref, struct port, kref);
-
- sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
- device_destroy(pdrvdata.class, port->dev->devt);
- cdev_del(port->cdev);
-
- kfree(port->name);
-
- debugfs_remove(port->debugfs_file);
-
- kfree(port);
-}
-
-/*
- * Port got unplugged. Remove port from portdev's list and drop the
- * kref reference. If no userspace has this port opened, it will
- * result in immediate removal the port.
- */
-static void unplug_port(struct port *port)
-{
- struct port_buffer *buf;
-
- spin_lock_irq(&port->portdev->ports_lock);
- list_del(&port->list);
- spin_unlock_irq(&port->portdev->ports_lock);
-
- if (port->guest_connected) {
- port->guest_connected = false;
- port->host_connected = false;
- wake_up_interruptible(&port->waitqueue);
-
- /* Let the app know the port is going down. */
- send_sigio_to_port(port);
- }
-
- if (is_console_port(port)) {
- spin_lock_irq(&pdrvdata_lock);
- list_del(&port->cons.list);
- spin_unlock_irq(&pdrvdata_lock);
-#if 0
- /*
- * hvc_remove() not called as removing one hvc port
- * results in other hvc ports getting frozen.
- *
- * Once this is resolved in hvc, this functionality
- * will be enabled. Till that is done, the -EPIPE
- * return from get_chars() above will help
- * hvc_console.c to clean up on ports we remove here.
- */
- hvc_remove(port->cons.hvc);
-#endif
- }
-
- /* Remove unused data this port might have received. */
- discard_port_data(port);
-
- reclaim_consumed_buffers(port);
-
- /* Remove buffers we queued up for the Host to send us data in. */
- while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
- free_buf(buf);
-
- /*
- * We should just assume the device itself has gone off --
- * else a close on an open port later will try to send out a
- * control message.
- */
- port->portdev = NULL;
-
- /*
- * Locks around here are not necessary - a port can't be
- * opened after we removed the port struct from ports_list
- * above.
- */
- kref_put(&port->kref, remove_port);
-}
-
-/* Any private messages that the Host and Guest want to share */
-static void handle_control_message(struct ports_device *portdev,
- struct port_buffer *buf)
-{
- struct virtio_console_control *cpkt;
- struct port *port;
- size_t name_size;
- int err;
-
- cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
-
- port = find_port_by_id(portdev, cpkt->id);
- if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) {
- /* No valid header at start of buffer. Drop it. */
- dev_dbg(&portdev->vdev->dev,
- "Invalid index %u in control packet\n", cpkt->id);
- return;
- }
-
- switch (cpkt->event) {
- case VIRTIO_CONSOLE_PORT_ADD:
- if (port) {
- dev_dbg(&portdev->vdev->dev,
- "Port %u already added\n", port->id);
- send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
- break;
- }
- if (cpkt->id >= portdev->config.max_nr_ports) {
- dev_warn(&portdev->vdev->dev,
- "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
- cpkt->id, portdev->config.max_nr_ports - 1);
- break;
- }
- add_port(portdev, cpkt->id);
- break;
- case VIRTIO_CONSOLE_PORT_REMOVE:
- unplug_port(port);
- break;
- case VIRTIO_CONSOLE_CONSOLE_PORT:
- if (!cpkt->value)
- break;
- if (is_console_port(port))
- break;
-
- init_port_console(port);
- /*
- * Could remove the port here in case init fails - but
- * have to notify the host first.
- */
- break;
- case VIRTIO_CONSOLE_RESIZE: {
- struct {
- __u16 rows;
- __u16 cols;
- } size;
-
- if (!is_console_port(port))
- break;
-
- memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
- sizeof(size));
- set_console_size(port, size.rows, size.cols);
-
- port->cons.hvc->irq_requested = 1;
- resize_console(port);
- break;
- }
- case VIRTIO_CONSOLE_PORT_OPEN:
- port->host_connected = cpkt->value;
- wake_up_interruptible(&port->waitqueue);
- /*
- * If the host port got closed and the host had any
- * unconsumed buffers, we'll be able to reclaim them
- * now.
- */
- spin_lock_irq(&port->outvq_lock);
- reclaim_consumed_buffers(port);
- spin_unlock_irq(&port->outvq_lock);
-
- /*
- * If the guest is connected, it'll be interested in
- * knowing the host connection state changed.
- */
- send_sigio_to_port(port);
- break;
- case VIRTIO_CONSOLE_PORT_NAME:
- /*
- * Skip the size of the header and the cpkt to get the size
- * of the name that was sent
- */
- name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
-
- port->name = kmalloc(name_size, GFP_KERNEL);
- if (!port->name) {
- dev_err(port->dev,
- "Not enough space to store port name\n");
- break;
- }
- strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
- name_size - 1);
- port->name[name_size - 1] = 0;
-
- /*
- * Since we only have one sysfs attribute, 'name',
- * create it only if we have a name for the port.
- */
- err = sysfs_create_group(&port->dev->kobj,
- &port_attribute_group);
- if (err) {
- dev_err(port->dev,
- "Error %d creating sysfs device attributes\n",
- err);
- } else {
- /*
- * Generate a udev event so that appropriate
- * symlinks can be created based on udev
- * rules.
- */
- kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
- }
- break;
- }
-}
-
-static void control_work_handler(struct work_struct *work)
-{
- struct ports_device *portdev;
- struct virtqueue *vq;
- struct port_buffer *buf;
- unsigned int len;
-
- portdev = container_of(work, struct ports_device, control_work);
- vq = portdev->c_ivq;
-
- spin_lock(&portdev->cvq_lock);
- while ((buf = virtqueue_get_buf(vq, &len))) {
- spin_unlock(&portdev->cvq_lock);
-
- buf->len = len;
- buf->offset = 0;
-
- handle_control_message(portdev, buf);
-
- spin_lock(&portdev->cvq_lock);
- if (add_inbuf(portdev->c_ivq, buf) < 0) {
- dev_warn(&portdev->vdev->dev,
- "Error adding buffer to queue\n");
- free_buf(buf);
- }
- }
- spin_unlock(&portdev->cvq_lock);
-}
-
-static void in_intr(struct virtqueue *vq)
-{
- struct port *port;
- unsigned long flags;
-
- port = find_port_by_vq(vq->vdev->priv, vq);
- if (!port)
- return;
-
- spin_lock_irqsave(&port->inbuf_lock, flags);
- if (!port->inbuf)
- port->inbuf = get_inbuf(port);
-
- /*
- * Don't queue up data when port is closed. This condition
- * can be reached when a console port is not yet connected (no
- * tty is spawned) and the host sends out data to console
- * ports. For generic serial ports, the host won't
- * (shouldn't) send data till the guest is connected.
- */
- if (!port->guest_connected)
- discard_port_data(port);
-
- spin_unlock_irqrestore(&port->inbuf_lock, flags);
-
- wake_up_interruptible(&port->waitqueue);
-
- /* Send a SIGIO indicating new data in case the process asked for it */
- send_sigio_to_port(port);
-
- if (is_console_port(port) && hvc_poll(port->cons.hvc))
- hvc_kick();
-}
-
-static void control_intr(struct virtqueue *vq)
-{
- struct ports_device *portdev;
-
- portdev = vq->vdev->priv;
- schedule_work(&portdev->control_work);
-}
-
-static void config_intr(struct virtio_device *vdev)
-{
- struct ports_device *portdev;
-
- portdev = vdev->priv;
-
- if (!use_multiport(portdev)) {
- struct port *port;
- u16 rows, cols;
-
- vdev->config->get(vdev,
- offsetof(struct virtio_console_config, cols),
- &cols, sizeof(u16));
- vdev->config->get(vdev,
- offsetof(struct virtio_console_config, rows),
- &rows, sizeof(u16));
-
- port = find_port_by_id(portdev, 0);
- set_console_size(port, rows, cols);
-
- /*
- * We'll use this way of resizing only for legacy
- * support. For newer userspace
- * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
- * to indicate console size changes so that it can be
- * done per-port.
- */
- resize_console(port);
- }
-}
-
-static int init_vqs(struct ports_device *portdev)
-{
- vq_callback_t **io_callbacks;
- char **io_names;
- struct virtqueue **vqs;
- u32 i, j, nr_ports, nr_queues;
- int err;
-
- nr_ports = portdev->config.max_nr_ports;
- nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
-
- vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
- io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
- io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
- portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
- GFP_KERNEL);
- portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
- GFP_KERNEL);
- if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs ||
- !portdev->out_vqs) {
- err = -ENOMEM;
- goto free;
- }
-
- /*
- * For backward compat (newer host but older guest), the host
- * spawns a console port first and also inits the vqs for port
- * 0 before others.
- */
- j = 0;
- io_callbacks[j] = in_intr;
- io_callbacks[j + 1] = NULL;
- io_names[j] = "input";
- io_names[j + 1] = "output";
- j += 2;
-
- if (use_multiport(portdev)) {
- io_callbacks[j] = control_intr;
- io_callbacks[j + 1] = NULL;
- io_names[j] = "control-i";
- io_names[j + 1] = "control-o";
-
- for (i = 1; i < nr_ports; i++) {
- j += 2;
- io_callbacks[j] = in_intr;
- io_callbacks[j + 1] = NULL;
- io_names[j] = "input";
- io_names[j + 1] = "output";
- }
- }
- /* Find the queues. */
- err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
- io_callbacks,
- (const char **)io_names);
- if (err)
- goto free;
-
- j = 0;
- portdev->in_vqs[0] = vqs[0];
- portdev->out_vqs[0] = vqs[1];
- j += 2;
- if (use_multiport(portdev)) {
- portdev->c_ivq = vqs[j];
- portdev->c_ovq = vqs[j + 1];
-
- for (i = 1; i < nr_ports; i++) {
- j += 2;
- portdev->in_vqs[i] = vqs[j];
- portdev->out_vqs[i] = vqs[j + 1];
- }
- }
- kfree(io_names);
- kfree(io_callbacks);
- kfree(vqs);
-
- return 0;
-
-free:
- kfree(portdev->out_vqs);
- kfree(portdev->in_vqs);
- kfree(io_names);
- kfree(io_callbacks);
- kfree(vqs);
-
- return err;
-}
-
-static const struct file_operations portdev_fops = {
- .owner = THIS_MODULE,
-};
-
-/*
- * Once we're further in boot, we get probed like any other virtio
- * device.
- *
- * If the host also supports multiple console ports, we check the
- * config space to see how many ports the host has spawned. We
- * initialize each port found.
- */
-static int __devinit virtcons_probe(struct virtio_device *vdev)
-{
- struct ports_device *portdev;
- int err;
- bool multiport;
-
- portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
- if (!portdev) {
- err = -ENOMEM;
- goto fail;
- }
-
- /* Attach this portdev to this virtio_device, and vice-versa. */
- portdev->vdev = vdev;
- vdev->priv = portdev;
-
- spin_lock_irq(&pdrvdata_lock);
- portdev->drv_index = pdrvdata.index++;
- spin_unlock_irq(&pdrvdata_lock);
-
- portdev->chr_major = register_chrdev(0, "virtio-portsdev",
- &portdev_fops);
- if (portdev->chr_major < 0) {
- dev_err(&vdev->dev,
- "Error %d registering chrdev for device %u\n",
- portdev->chr_major, portdev->drv_index);
- err = portdev->chr_major;
- goto free;
- }
-
- multiport = false;
- portdev->config.max_nr_ports = 1;
- if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
- multiport = true;
- vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
-
- vdev->config->get(vdev, offsetof(struct virtio_console_config,
- max_nr_ports),
- &portdev->config.max_nr_ports,
- sizeof(portdev->config.max_nr_ports));
- }
-
- /* Let the Host know we support multiple ports.*/
- vdev->config->finalize_features(vdev);
-
- err = init_vqs(portdev);
- if (err < 0) {
- dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
- goto free_chrdev;
- }
-
- spin_lock_init(&portdev->ports_lock);
- INIT_LIST_HEAD(&portdev->ports);
-
- if (multiport) {
- unsigned int nr_added_bufs;
-
- spin_lock_init(&portdev->cvq_lock);
- INIT_WORK(&portdev->control_work, &control_work_handler);
-
- nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
- if (!nr_added_bufs) {
- dev_err(&vdev->dev,
- "Error allocating buffers for control queue\n");
- err = -ENOMEM;
- goto free_vqs;
- }
- } else {
- /*
- * For backward compatibility: Create a console port
- * if we're running on older host.
- */
- add_port(portdev, 0);
- }
-
- spin_lock_irq(&pdrvdata_lock);
- list_add_tail(&portdev->list, &pdrvdata.portdevs);
- spin_unlock_irq(&pdrvdata_lock);
-
- __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
- VIRTIO_CONSOLE_DEVICE_READY, 1);
- return 0;
-
-free_vqs:
- /* The host might want to notify mgmt sw about device add failure */
- __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
- VIRTIO_CONSOLE_DEVICE_READY, 0);
- vdev->config->del_vqs(vdev);
- kfree(portdev->in_vqs);
- kfree(portdev->out_vqs);
-free_chrdev:
- unregister_chrdev(portdev->chr_major, "virtio-portsdev");
-free:
- kfree(portdev);
-fail:
- return err;
-}
-
-static void virtcons_remove(struct virtio_device *vdev)
-{
- struct ports_device *portdev;
- struct port *port, *port2;
-
- portdev = vdev->priv;
-
- spin_lock_irq(&pdrvdata_lock);
- list_del(&portdev->list);
- spin_unlock_irq(&pdrvdata_lock);
-
- /* Disable interrupts for vqs */
- vdev->config->reset(vdev);
- /* Finish up work that's lined up */
- cancel_work_sync(&portdev->control_work);
-
- list_for_each_entry_safe(port, port2, &portdev->ports, list)
- unplug_port(port);
-
- unregister_chrdev(portdev->chr_major, "virtio-portsdev");
-
- /*
- * When yanking out a device, we immediately lose the
- * (device-side) queues. So there's no point in keeping the
- * guest side around till we drop our final reference. This
- * also means that any ports which are in an open state will
- * have to just stop using the port, as the vqs are going
- * away.
- */
- if (use_multiport(portdev)) {
- struct port_buffer *buf;
- unsigned int len;
-
- while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
- free_buf(buf);
-
- while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
- free_buf(buf);
- }
-
- vdev->config->del_vqs(vdev);
- kfree(portdev->in_vqs);
- kfree(portdev->out_vqs);
-
- kfree(portdev);
-}
-
-static struct virtio_device_id id_table[] = {
- { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
- { 0 },
-};
-
-static unsigned int features[] = {
- VIRTIO_CONSOLE_F_SIZE,
- VIRTIO_CONSOLE_F_MULTIPORT,
-};
-
-static struct virtio_driver virtio_console = {
- .feature_table = features,
- .feature_table_size = ARRAY_SIZE(features),
- .driver.name = KBUILD_MODNAME,
- .driver.owner = THIS_MODULE,
- .id_table = id_table,
- .probe = virtcons_probe,
- .remove = virtcons_remove,
- .config_changed = config_intr,
-};
-
-static int __init init(void)
-{
- int err;
-
- pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
- if (IS_ERR(pdrvdata.class)) {
- err = PTR_ERR(pdrvdata.class);
- pr_err("Error %d creating virtio-ports class\n", err);
- return err;
- }
-
- pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
- if (!pdrvdata.debugfs_dir) {
- pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
- PTR_ERR(pdrvdata.debugfs_dir));
- }
- INIT_LIST_HEAD(&pdrvdata.consoles);
- INIT_LIST_HEAD(&pdrvdata.portdevs);
-
- return register_virtio_driver(&virtio_console);
-}
-
-static void __exit fini(void)
-{
- unregister_virtio_driver(&virtio_console);
-
- class_destroy(pdrvdata.class);
- if (pdrvdata.debugfs_dir)
- debugfs_remove_recursive(pdrvdata.debugfs_dir);
-}
-module_init(init);
-module_exit(fini);
-
-MODULE_DEVICE_TABLE(virtio, id_table);
-MODULE_DESCRIPTION("Virtio console driver");
-MODULE_LICENSE("GPL");
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