Skip to content

Commit

Permalink
virtio: console: struct ports for multiple ports per device.
Browse files Browse the repository at this point in the history 
Rather than assume a single port, add a 'struct ports_device' which
stores data related to all the ports for that device.

Currently, there's only one port and is hooked up with hvc, but that
will change.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
  • Loading branch information
Amit Shah authored and Rusty Russell committed Feb 24, 2010
1 parent d8a02bd commit 1c85bf3
Showing 1 changed file with 89 additions and 63 deletions.
152 changes: 89 additions & 63 deletions drivers/char/virtio_console.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -51,6 +51,15 @@ static struct ports_driver_data pdrvdata;

DEFINE_SPINLOCK(pdrvdata_lock);

/*
* This is a per-device struct that stores data common to all the
* ports for that device (vdev->priv).
*/
struct ports_device {
struct virtqueue *in_vq, *out_vq;
struct virtio_device *vdev;
};

struct port_buffer {
char *buf;

Expand All @@ -63,13 +72,17 @@ struct port_buffer {
size_t offset;
};

/* This struct holds the per-port data */
struct port {
struct virtqueue *in_vq, *out_vq;
struct virtio_device *vdev;
/* 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;

/* The IO vqs for this port */
struct virtqueue *in_vq, *out_vq;

/* For console ports, hvc != NULL and these are valid. */
/* The hvc device */
struct hvc_struct *hvc;
Expand Down Expand Up @@ -152,6 +165,7 @@ static void *get_inbuf(struct port *port)
static void add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
{
struct scatterlist sg[1];

sg_init_one(sg, buf->buf, buf->size);

if (vq->vq_ops->add_buf(vq, sg, 0, 1, buf) < 0)
Expand All @@ -171,6 +185,7 @@ static int put_chars(u32 vtermno, const char *buf, int count)
{
struct scatterlist sg[1];
struct port *port;
struct virtqueue *out_vq;
unsigned int len;

port = find_port_by_vtermno(vtermno);
Expand All @@ -180,14 +195,15 @@ static int put_chars(u32 vtermno, const char *buf, int count)
if (unlikely(early_put_chars))
return early_put_chars(vtermno, buf, count);

out_vq = port->out_vq;
/* This is a convenient routine to initialize a single-elem sg list */
sg_init_one(sg, buf, count);

/* This shouldn't fail: if it does, we lose chars. */
if (port->out_vq->vq_ops->add_buf(port->out_vq, sg, 1, 0, port) >= 0) {
if (out_vq->vq_ops->add_buf(out_vq, sg, 1, 0, port) >= 0) {
/* Tell Host to go! */
port->out_vq->vq_ops->kick(port->out_vq);
while (!port->out_vq->vq_ops->get_buf(port->out_vq, &len))
out_vq->vq_ops->kick(out_vq);
while (!out_vq->vq_ops->get_buf(out_vq, &len))
cpu_relax();
}

Expand All @@ -207,7 +223,6 @@ static int get_chars(u32 vtermno, char *buf, int count)
{
struct port *port;


port = find_port_by_vtermno(vtermno);
if (!port)
return 0;
Expand Down Expand Up @@ -242,7 +257,6 @@ static int get_chars(u32 vtermno, char *buf, int count)
*/
static void virtcons_apply_config(struct virtio_device *dev)
{
struct port *port = dev->priv;
struct winsize ws;

if (virtio_has_feature(dev, VIRTIO_CONSOLE_F_SIZE)) {
Expand All @@ -252,7 +266,9 @@ static void virtcons_apply_config(struct virtio_device *dev)
dev->config->get(dev,
offsetof(struct virtio_console_config, rows),
&ws.ws_row, sizeof(u16));
hvc_resize(port->hvc, ws);
/* This is the pre-multiport style: we use control messages
* these days which specify the port. So this means port 0. */
hvc_resize(find_port_by_vtermno(0)->hvc, ws);
}
}

Expand All @@ -266,7 +282,7 @@ static int notifier_add_vio(struct hvc_struct *hp, int data)
return -EINVAL;

hp->irq_requested = 1;
virtcons_apply_config(port->vdev);
virtcons_apply_config(port->portdev->vdev);

return 0;
}
Expand All @@ -278,9 +294,13 @@ static void notifier_del_vio(struct hvc_struct *hp, int data)

static void hvc_handle_input(struct virtqueue *vq)
{
struct port *port = vq->vdev->priv;
struct port *port;
bool activity = false;

list_for_each_entry(port, &pdrvdata.consoles, list)
activity |= hvc_poll(port->hvc);

if (hvc_poll(port->hvc))
if (activity)
hvc_kick();
}

Expand Down Expand Up @@ -308,66 +328,26 @@ int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
return hvc_instantiate(0, 0, &hv_ops);
}

static struct port *__devinit add_port(u32 vtermno)
{
struct port *port;

port = kmalloc(sizeof(*port), GFP_KERNEL);
if (!port)
return NULL;

port->inbuf = alloc_buf(PAGE_SIZE);
if (!port->inbuf) {
kfree(port);
return NULL;
}
port->hvc = NULL;
port->vtermno = vtermno;
return port;
}

static void free_port(struct port *port)
static int __devinit add_port(struct ports_device *portdev)
{
free_buf(port->inbuf);
kfree(port);
}

/*
* Once we're further in boot, we get probed like any other virtio
* device. At this stage we set up the output virtqueue.
*
* To set up and manage our virtual console, we call hvc_alloc().
* Since we never remove the console device we never need this pointer
* again.
*
* Finally we put our input buffer in the input queue, ready to
* receive.
*/
static int __devinit virtcons_probe(struct virtio_device *vdev)
{
vq_callback_t *callbacks[] = { hvc_handle_input, NULL};
const char *names[] = { "input", "output" };
struct virtqueue *vqs[2];
struct port *port;
int err;

port = add_port(pdrvdata.next_vtermno);
port = kmalloc(sizeof(*port), GFP_KERNEL);
if (!port) {
err = -ENOMEM;
goto fail;
}

/* Attach this port to this virtio_device, and vice-versa. */
port->vdev = vdev;
vdev->priv = port;
port->portdev = portdev;
port->in_vq = portdev->in_vq;
port->out_vq = portdev->out_vq;

/* Find the queues. */
err = vdev->config->find_vqs(vdev, 2, vqs, callbacks, names);
if (err)
goto free;

port->in_vq = vqs[0];
port->out_vq = vqs[1];
port->inbuf = alloc_buf(PAGE_SIZE);
if (!port->inbuf) {
err = -ENOMEM;
goto free_port;
}

/*
* The first argument of hvc_alloc() is the virtual console
Expand All @@ -380,10 +360,11 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
* pointers. The final argument is the output buffer size: we
* can do any size, so we put PAGE_SIZE here.
*/
port->vtermno = pdrvdata.next_vtermno;
port->hvc = hvc_alloc(port->vtermno, 0, &hv_ops, PAGE_SIZE);
if (IS_ERR(port->hvc)) {
err = PTR_ERR(port->hvc);
goto free_vqs;
goto free_inbuf;
}

/* Add to vtermno list. */
Expand All @@ -395,14 +376,59 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
/* Register the input buffer the first time. */
add_inbuf(port->in_vq, port->inbuf);

return 0;

free_inbuf:
free_buf(port->inbuf);
free_port:
kfree(port);
fail:
return err;
}

/*
* Once we're further in boot, we get probed like any other virtio
* device.
*/
static int __devinit virtcons_probe(struct virtio_device *vdev)
{
vq_callback_t *callbacks[] = { hvc_handle_input, NULL};
const char *names[] = { "input", "output" };
struct virtqueue *vqs[2];
struct ports_device *portdev;
int err;

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;

/* Find the queues. */
err = vdev->config->find_vqs(vdev, 2, vqs, callbacks, names);
if (err)
goto free;

portdev->in_vq = vqs[0];
portdev->out_vq = vqs[1];

/* We only have one port. */
err = add_port(portdev);
if (err)
goto free_vqs;

/* Start using the new console output. */
early_put_chars = NULL;
return 0;

free_vqs:
vdev->config->del_vqs(vdev);
free:
free_port(port);
kfree(portdev);
fail:
return err;
}
Expand Down

0 comments on commit 1c85bf3

Please sign in to comment.