/*
* 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
#include <linux/spinlock.h>
#include <linux/virtio.h>
#include <linux/virtio_console.h>
+#include <linux/workqueue.h>
#include "hvc_console.h"
/*
u32 vtermno;
};
-/*
- * This is a per-device struct that stores data common to all the
- * ports for that device (vdev->priv).
- */
-struct ports_device {
- /* Array of per-port IO virtqueues */
- struct virtqueue **in_vqs, **out_vqs;
-
- struct virtio_device *vdev;
-};
-
struct port_buffer {
char *buf;
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 {
+ /*
+ * 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;
+};
+
/* 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;
* hooked up to an hvc console
*/
struct console cons;
+
+ /* The 'id' to identify the port with the Host */
+ u32 id;
};
/* This is the very early arch-specified put chars function. */
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;
- struct console *cons;
unsigned long flags;
- spin_lock_irqsave(&pdrvdata_lock, flags);
- list_for_each_entry(cons, &pdrvdata.consoles, list) {
- port = container_of(cons, struct port, cons);
+ 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(&pdrvdata_lock, flags);
+ 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);
return ret;
}
+static ssize_t send_control_msg(struct port *port, unsigned int event,
+ unsigned int value)
+{
+ struct scatterlist sg[1];
+ struct virtio_console_control cpkt;
+ struct virtqueue *vq;
+ int len;
+
+ if (!use_multiport(port->portdev))
+ return 0;
+
+ cpkt.id = port->id;
+ cpkt.event = event;
+ cpkt.value = value;
+
+ vq = port->portdev->c_ovq;
+
+ sg_init_one(sg, &cpkt, sizeof(cpkt));
+ if (vq->vq_ops->add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
+ vq->vq_ops->kick(vq);
+ while (!vq->vq_ops->get_buf(vq, &len))
+ cpu_relax();
+ }
+ return 0;
+}
+
static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count)
{
struct scatterlist sg[1];
hp->irq_requested = 0;
}
-static void hvc_handle_input(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);
- port->inbuf = get_inbuf(port);
- spin_unlock_irqrestore(&port->inbuf_lock, flags);
-
- if (hvc_poll(port->cons.hvc))
- hvc_kick();
-}
-
-/* The operations for the console. */
+/* The operations for console ports. */
static const struct hv_ops hv_ops = {
.get_chars = get_chars,
.put_chars = put_chars,
return hvc_instantiate(0, 0, &hv_ops);
}
-int __devinit init_port_console(struct port *port)
+int init_port_console(struct port *port)
{
int ret;
return 0;
}
-static int __devinit add_port(struct ports_device *portdev)
+/* 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;
+
+ cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
+
+ port = find_port_by_id(portdev, cpkt->id);
+ if (!port) {
+ /* 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_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:
+ if (!is_console_port(port))
+ break;
+ port->cons.hvc->irq_requested = 1;
+ resize_console(port);
+ 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 = vq->vq_ops->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);
+ port->inbuf = get_inbuf(port);
+
+ spin_unlock_irqrestore(&port->inbuf_lock, flags);
+
+ 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 fill_queue(struct virtqueue *vq, spinlock_t *lock)
+{
+ struct port_buffer *buf;
+ int ret;
+
+ 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;
+ }
+ spin_unlock_irq(lock);
+ } while (ret > 0);
+}
+
+static int add_port(struct ports_device *portdev, u32 id)
{
struct port *port;
struct port_buffer *inbuf;
}
port->portdev = portdev;
+ port->id = id;
port->inbuf = NULL;
+ port->cons.hvc = NULL;
- port->in_vq = portdev->in_vqs[0];
- port->out_vq = portdev->out_vqs[0];
+ port->in_vq = portdev->in_vqs[port->id];
+ port->out_vq = portdev->out_vqs[port->id];
spin_lock_init(&port->inbuf_lock);
/* Register the input buffer the first time. */
add_inbuf(port->in_vq, inbuf);
- err = init_port_console(port);
- if (err)
- goto free_inbuf;
+ /*
+ * 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_inbuf;
+ }
+
+ 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);
return 0;
vq_callback_t **io_callbacks;
char **io_names;
struct virtqueue **vqs;
- u32 nr_ports, nr_queues;
+ u32 i, j, nr_ports, nr_queues;
int err;
- /* We currently only have one port and two queues for that port */
- nr_ports = 1;
- nr_queues = 2;
+ 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);
if (!vqs) {
goto free_invqs;
}
- io_callbacks[0] = hvc_handle_input;
- io_callbacks[1] = NULL;
- io_names[0] = "input";
- io_names[1] = "output";
-
+ /*
+ * 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,
if (err)
goto free_outvqs;
+ 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_callbacks);
kfree(io_names);
kfree(vqs);
/*
* 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;
+ u32 i;
int err;
+ bool multiport;
portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
if (!portdev) {
portdev->vdev = vdev;
vdev->priv = portdev;
+ multiport = false;
+ portdev->config.nr_ports = 1;
+ 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,
+ nr_ports),
+ &portdev->config.nr_ports,
+ sizeof(portdev->config.nr_ports));
+ vdev->config->get(vdev, offsetof(struct virtio_console_config,
+ max_nr_ports),
+ &portdev->config.max_nr_ports,
+ sizeof(portdev->config.max_nr_ports));
+ if (portdev->config.nr_ports > portdev->config.max_nr_ports) {
+ dev_warn(&vdev->dev,
+ "More ports (%u) specified than allowed (%u). Will init %u ports.",
+ portdev->config.nr_ports,
+ portdev->config.max_nr_ports,
+ portdev->config.max_nr_ports);
+
+ portdev->config.nr_ports = 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;
}
- /* We only have one port. */
- err = add_port(portdev);
- if (err)
- goto free_vqs;
+ spin_lock_init(&portdev->ports_lock);
+ INIT_LIST_HEAD(&portdev->ports);
+
+ if (multiport) {
+ spin_lock_init(&portdev->cvq_lock);
+ INIT_WORK(&portdev->control_work, &control_work_handler);
+
+ fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+ }
+
+ for (i = 0; i < portdev->config.nr_ports; i++)
+ add_port(portdev, i);
/* Start using the new console output. */
early_put_chars = NULL;
static unsigned int features[] = {
VIRTIO_CONSOLE_F_SIZE,
+ VIRTIO_CONSOLE_F_MULTIPORT,
};
static struct virtio_driver virtio_console = {
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