diff --git a/MAINTAINERS b/MAINTAINERS index d371022..63c3620 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2336,12 +2336,6 @@ L: linuxppc-dev@ozlabs.org S: Odd Fixes F: drivers/char/hvc_* -VIRTIO CONSOLE DRIVER -M: Amit Shah -L: virtualization@lists.linux-foundation.org -S: Maintained -F: drivers/char/virtio_console.c - GSPCA FINEPIX SUBDRIVER M: Frank Zago L: linux-media@vger.kernel.org @@ -5682,6 +5676,13 @@ S: Maintained F: Documentation/filesystems/vfat.txt F: fs/fat/ +VIRTIO CONSOLE DRIVER +M: Amit Shah +L: virtualization@lists.linux-foundation.org +S: Maintained +F: drivers/char/virtio_console.c +F: include/linux/virtio_console.h + VIRTIO HOST (VHOST) M: "Michael S. Tsirkin" L: kvm@vger.kernel.org diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 213373b..ab29b98 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -109,7 +109,6 @@ struct ports_device { * notification */ struct work_struct control_work; - struct work_struct config_work; struct list_head ports; @@ -159,6 +158,9 @@ struct port { */ 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; @@ -184,6 +186,8 @@ struct port { /* The 'id' to identify the port with the Host */ u32 id; + bool outvq_full; + /* Is the host device open */ bool host_connected; @@ -373,22 +377,22 @@ out: return ret; } -static ssize_t send_control_msg(struct port *port, unsigned int event, - unsigned int value) +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; - int len; + unsigned int len; - if (!use_multiport(port->portdev)) + if (!use_multiport(portdev)) return 0; - cpkt.id = port->id; + cpkt.id = port_id; cpkt.event = event; cpkt.value = value; - vq = port->portdev->c_ovq; + vq = portdev->c_ovq; sg_init_one(sg, &cpkt, sizeof(cpkt)); if (vq->vq_ops->add_buf(vq, sg, 1, 0, &cpkt) >= 0) { @@ -399,15 +403,39 @@ static ssize_t send_control_msg(struct port *port, unsigned int event, return 0; } -static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count) +static ssize_t send_control_msg(struct port *port, unsigned int event, + unsigned int value) +{ + return __send_control_msg(port->portdev, port->id, event, value); +} + +/* Callers must take the port->outvq_lock */ +static void reclaim_consumed_buffers(struct port *port) +{ + void *buf; + unsigned int len; + + while ((buf = port->out_vq->vq_ops->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 = out_vq->vq_ops->add_buf(out_vq, sg, 1, 0, in_buf); @@ -415,20 +443,31 @@ static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count) out_vq->vq_ops->kick(out_vq); if (ret < 0) { - len = 0; - goto fail; + 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. Also ensure we return to userspace the number of - * bytes that were successfully consumed by the host. + * sent. This is done for ports in blocking mode or for data + * from the hvc_console; the tty operations are performed with + * spinlocks held so we can't sleep here. */ while (!out_vq->vq_ops->get_buf(out_vq, &len)) cpu_relax(); -fail: - /* We're expected to return the amount of data we wrote */ - return len; +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; } /* @@ -477,9 +516,28 @@ static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count, } /* The condition that must be true for polling to end */ -static bool wait_is_over(struct port *port) +static bool will_read_block(struct port *port) +{ + return !port_has_data(port) && port->host_connected; +} + +static bool will_write_block(struct port *port) { - return port_has_data(port) || !port->host_connected; + bool ret; + + 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, @@ -502,7 +560,7 @@ static ssize_t port_fops_read(struct file *filp, char __user *ubuf, return -EAGAIN; ret = wait_event_interruptible(port->waitqueue, - wait_is_over(port)); + !will_read_block(port)); if (ret < 0) return ret; } @@ -528,9 +586,22 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf, struct port *port; char *buf; ssize_t ret; + bool nonblock; 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; + } + count = min((size_t)(32 * 1024), count); buf = kmalloc(count, GFP_KERNEL); @@ -543,9 +614,14 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf, goto free_buf; } - ret = send_buf(port, buf, count); + ret = send_buf(port, buf, count, nonblock); + + if (nonblock && ret > 0) + goto out; + free_buf: kfree(buf); +out: return ret; } @@ -560,7 +636,7 @@ static unsigned int port_fops_poll(struct file *filp, poll_table *wait) ret = 0; if (port->inbuf) ret |= POLLIN | POLLRDNORM; - if (port->host_connected) + if (!will_write_block(port)) ret |= POLLOUT; if (!port->host_connected) ret |= POLLHUP; @@ -584,6 +660,10 @@ static int port_fops_release(struct inode *inode, struct file *filp) spin_unlock_irq(&port->inbuf_lock); + spin_lock_irq(&port->outvq_lock); + reclaim_consumed_buffers(port); + spin_unlock_irq(&port->outvq_lock); + return 0; } @@ -612,6 +692,15 @@ static int port_fops_open(struct inode *inode, struct file *filp) 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); + /* Notify host of port being opened */ send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1); @@ -645,14 +734,14 @@ static int put_chars(u32 vtermno, const char *buf, int count) { struct port *port; - port = find_port_by_vtermno(vtermno); - if (!port) - return 0; - if (unlikely(early_put_chars)) return early_put_chars(vtermno, buf, count); - return send_buf(port, (void *)buf, count); + port = find_port_by_vtermno(vtermno); + if (!port) + return -EPIPE; + + return send_buf(port, (void *)buf, count, false); } /* @@ -666,9 +755,13 @@ 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 0; + return -EPIPE; /* If we don't have an input queue yet, we can't get input. */ BUG_ON(!port->in_vq); @@ -681,6 +774,10 @@ static void resize_console(struct port *port) struct virtio_device *vdev; struct winsize ws; + /* The port could have been hot-unplugged */ + if (!port) + return; + vdev = port->portdev->vdev; if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)) { vdev->config->get(vdev, @@ -774,6 +871,13 @@ int init_port_console(struct port *port) 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); @@ -829,6 +933,8 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf, 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, @@ -845,6 +951,140 @@ static const struct file_operations port_debugfs_ops = { .read = debugfs_read, }; +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 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; + } + + port->portdev = portdev; + port->id = id; + + port->name = NULL; + port->inbuf = NULL; + port->cons.hvc = NULL; + + 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]; + + cdev_init(&port->cdev, &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_port; + } + 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 = port->in_vq->vq_ops->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: + return err; +} + /* Remove all port-specific data. */ static int remove_port(struct port *port) { @@ -858,7 +1098,18 @@ static int remove_port(struct 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 } if (port->guest_connected) send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0); @@ -870,6 +1121,8 @@ static int remove_port(struct port *port) /* 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 = port->in_vq->vq_ops->detach_unused_buf(port->in_vq))) free_buf(buf); @@ -894,7 +1147,7 @@ static void handle_control_message(struct ports_device *portdev, cpkt = (struct virtio_console_control *)(buf->buf + buf->offset); port = find_port_by_id(portdev, cpkt->id); - if (!port) { + 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); @@ -902,6 +1155,24 @@ static void handle_control_message(struct ports_device *portdev, } 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: + remove_port(port); + break; case VIRTIO_CONSOLE_CONSOLE_PORT: if (!cpkt->value) break; @@ -923,6 +1194,14 @@ static void handle_control_message(struct ports_device *portdev, 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); break; case VIRTIO_CONSOLE_PORT_NAME: /* @@ -947,37 +1226,18 @@ static void handle_control_message(struct ports_device *portdev, */ err = sysfs_create_group(&port->dev->kobj, &port_attribute_group); - if (err) + if (err) { dev_err(port->dev, "Error %d creating sysfs device attributes\n", err); - - break; - case VIRTIO_CONSOLE_PORT_REMOVE: - /* - * Hot unplug the port. We don't decrement nr_ports - * since we don't want to deal with extra complexities - * of using the lowest-available port id: We can just - * pick up the nr_ports number as the id and not have - * userspace send it to us. This helps us in two - * ways: - * - * - We don't need to have a 'port_id' field in the - * config space when a port is hot-added. This is a - * good thing as we might queue up multiple hotplug - * requests issued in our workqueue. - * - * - Another way to deal with this would have been to - * use a bitmap of the active ports and select the - * lowest non-active port from that map. That - * bloats the already tight config space and we - * would end up artificially limiting the - * max. number of ports to sizeof(bitmap). Right - * now we can support 2^32 ports (as the port id is - * stored in a u32 type). - * - */ - remove_port(port); + } else { + /* + * Generate a udev event so that appropriate + * symlinks can be created based on udev + * rules. + */ + kobject_uevent(&port->dev->kobj, KOBJ_CHANGE); + } break; } } @@ -1055,10 +1315,7 @@ static void config_intr(struct virtio_device *vdev) struct ports_device *portdev; portdev = vdev->priv; - if (use_multiport(portdev)) { - /* Handle port hot-add */ - schedule_work(&portdev->config_work); - } + /* * We'll use this way of resizing only for legacy support. * For newer userspace (VIRTIO_CONSOLE_F_MULTPORT+), use @@ -1068,192 +1325,6 @@ static void config_intr(struct virtio_device *vdev) resize_console(find_port_by_id(portdev, 0)); } -static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock) -{ - struct port_buffer *buf; - unsigned int ret; - int err; - - ret = 0; - do { - buf = alloc_buf(PAGE_SIZE); - if (!buf) - break; - - spin_lock_irq(lock); - err = add_inbuf(vq, buf); - if (err < 0) { - spin_unlock_irq(lock); - free_buf(buf); - break; - } - ret++; - spin_unlock_irq(lock); - } while (err > 0); - - return ret; -} - -static int add_port(struct ports_device *portdev, u32 id) -{ - char debugfs_name[16]; - struct port *port; - struct port_buffer *buf; - dev_t devt; - int err; - - port = kmalloc(sizeof(*port), GFP_KERNEL); - if (!port) { - err = -ENOMEM; - goto fail; - } - - port->portdev = portdev; - port->id = id; - - port->name = NULL; - port->inbuf = NULL; - port->cons.hvc = NULL; - - port->host_connected = port->guest_connected = false; - - port->in_vq = portdev->in_vqs[port->id]; - port->out_vq = portdev->out_vqs[port->id]; - - cdev_init(&port->cdev, &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_port; - } - 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); - init_waitqueue_head(&port->waitqueue); - - /* Fill the in_vq with buffers so the host can send us data. */ - err = fill_queue(port->in_vq, &port->inbuf_lock); - if (!err) { - 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 = port->in_vq->vq_ops->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: - return err; -} - -/* - * The workhandler for config-space updates. - * - * This is called when ports are hot-added. - */ -static void config_work_handler(struct work_struct *work) -{ - struct virtio_console_config virtconconf; - struct ports_device *portdev; - struct virtio_device *vdev; - int err; - - portdev = container_of(work, struct ports_device, config_work); - - vdev = portdev->vdev; - vdev->config->get(vdev, - offsetof(struct virtio_console_config, nr_ports), - &virtconconf.nr_ports, - sizeof(virtconconf.nr_ports)); - - if (portdev->config.nr_ports == virtconconf.nr_ports) { - /* - * Port 0 got hot-added. Since we already did all the - * other initialisation for it, just tell the Host - * that the port is ready if we find the port. In - * case the port was hot-removed earlier, we call - * add_port to add the port. - */ - struct port *port; - - port = find_port_by_id(portdev, 0); - if (!port) - add_port(portdev, 0); - else - send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); - return; - } - if (virtconconf.nr_ports > portdev->config.max_nr_ports) { - dev_warn(&vdev->dev, - "More ports specified (%u) than allowed (%u)", - portdev->config.nr_ports + 1, - portdev->config.max_nr_ports); - return; - } - if (virtconconf.nr_ports < portdev->config.nr_ports) - return; - - /* Hot-add ports */ - while (virtconconf.nr_ports - portdev->config.nr_ports) { - err = add_port(portdev, portdev->config.nr_ports); - if (err) - break; - portdev->config.nr_ports++; - } -} - static int init_vqs(struct ports_device *portdev) { vq_callback_t **io_callbacks; @@ -1375,7 +1446,6 @@ static const struct file_operations portdev_fops = { static int __devinit virtcons_probe(struct virtio_device *vdev) { struct ports_device *portdev; - u32 i; int err; bool multiport; @@ -1404,29 +1474,15 @@ static int __devinit virtcons_probe(struct virtio_device *vdev) } 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.*/ @@ -1442,24 +1498,28 @@ static int __devinit virtcons_probe(struct virtio_device *vdev) 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); - INIT_WORK(&portdev->config_work, &config_work_handler); - err = fill_queue(portdev->c_ivq, &portdev->cvq_lock); - if (!err) { + 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); } - for (i = 0; i < portdev->config.nr_ports; i++) - add_port(portdev, i); - - /* Start using the new console output. */ - early_put_chars = NULL; + __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID, + VIRTIO_CONSOLE_DEVICE_READY, 1); return 0; free_vqs: @@ -1471,6 +1531,9 @@ free_chrdev: free: kfree(portdev); fail: + /* 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); return err; } @@ -1484,7 +1547,6 @@ static void virtcons_remove(struct virtio_device *vdev) portdev = vdev->priv; cancel_work_sync(&portdev->control_work); - cancel_work_sync(&portdev->config_work); list_for_each_entry_safe(port, port2, &portdev->ports, list) remove_port(port); diff --git a/include/linux/virtio_console.h b/include/linux/virtio_console.h index ae4f039..a85064d 100644 --- a/include/linux/virtio_console.h +++ b/include/linux/virtio_console.h @@ -14,6 +14,8 @@ #define VIRTIO_CONSOLE_F_SIZE 0 /* Does host provide console size? */ #define VIRTIO_CONSOLE_F_MULTIPORT 1 /* Does host provide multiple ports? */ +#define VIRTIO_CONSOLE_BAD_ID (~(u32)0) + struct virtio_console_config { /* colums of the screens */ __u16 cols; @@ -21,8 +23,6 @@ struct virtio_console_config { __u16 rows; /* max. number of ports this device can hold */ __u32 max_nr_ports; - /* number of ports added so far */ - __u32 nr_ports; } __attribute__((packed)); /* @@ -36,12 +36,14 @@ struct virtio_console_control { }; /* Some events for control messages */ -#define VIRTIO_CONSOLE_PORT_READY 0 -#define VIRTIO_CONSOLE_CONSOLE_PORT 1 -#define VIRTIO_CONSOLE_RESIZE 2 -#define VIRTIO_CONSOLE_PORT_OPEN 3 -#define VIRTIO_CONSOLE_PORT_NAME 4 -#define VIRTIO_CONSOLE_PORT_REMOVE 5 +#define VIRTIO_CONSOLE_DEVICE_READY 0 +#define VIRTIO_CONSOLE_PORT_ADD 1 +#define VIRTIO_CONSOLE_PORT_REMOVE 2 +#define VIRTIO_CONSOLE_PORT_READY 3 +#define VIRTIO_CONSOLE_CONSOLE_PORT 4 +#define VIRTIO_CONSOLE_RESIZE 5 +#define VIRTIO_CONSOLE_PORT_OPEN 6 +#define VIRTIO_CONSOLE_PORT_NAME 7 #ifdef __KERNEL__ int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int));