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authorLinus Torvalds <torvalds@linux-foundation.org>2013-08-08 09:32:20 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-08-08 09:32:20 -0700
commitbb014db07ce04851f0e19ef5c0f15ad0021ec38c (patch)
treecd5bcbd14c2e25d499bea95211f94074487b3d26
parent67ef62650694d2e8c367855084a8c4af9985b7b7 (diff)
parentaa52aeea2725839bdd3dcce394486e9a043065e0 (diff)
downloadlinux-bb014db07ce04851f0e19ef5c0f15ad0021ec38c.tar.bz2
Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio fixes from Rusty Russell: "More virtio console fixes than I'm happy with, but all real issues, and all CC:stable.." * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: virtio-scsi: Fix virtqueue affinity setup virtio: console: return -ENODEV on all read operations after unplug virtio: console: fix raising SIGIO after port unplug virtio: console: clean up port data immediately at time of unplug virtio: console: fix race in port_fops_open() and port unplug virtio: console: fix race with port unplug and open/close virtio/console: Add pipe_lock/unlock for splice_write virtio/console: Quit from splice_write if pipe->nrbufs is 0
-rw-r--r--drivers/char/virtio_console.c70
-rw-r--r--drivers/scsi/virtio_scsi.c2
2 files changed, 49 insertions, 23 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 1b456fe9b87a..fc45567ad3ac 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -272,9 +272,12 @@ static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
unsigned long flags;
spin_lock_irqsave(&portdev->ports_lock, flags);
- list_for_each_entry(port, &portdev->ports, list)
- if (port->cdev->dev == dev)
+ list_for_each_entry(port, &portdev->ports, list) {
+ if (port->cdev->dev == dev) {
+ kref_get(&port->kref);
goto out;
+ }
+ }
port = NULL;
out:
spin_unlock_irqrestore(&portdev->ports_lock, flags);
@@ -746,6 +749,10 @@ static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
port = filp->private_data;
+ /* Port is hot-unplugged. */
+ if (!port->guest_connected)
+ return -ENODEV;
+
if (!port_has_data(port)) {
/*
* If nothing's connected on the host just return 0 in
@@ -762,7 +769,7 @@ static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
if (ret < 0)
return ret;
}
- /* Port got hot-unplugged. */
+ /* Port got hot-unplugged while we were waiting above. */
if (!port->guest_connected)
return -ENODEV;
/*
@@ -932,13 +939,25 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe,
if (is_rproc_serial(port->out_vq->vdev))
return -EINVAL;
+ /*
+ * pipe->nrbufs == 0 means there are no data to transfer,
+ * so this returns just 0 for no data.
+ */
+ pipe_lock(pipe);
+ if (!pipe->nrbufs) {
+ ret = 0;
+ goto error_out;
+ }
+
ret = wait_port_writable(port, filp->f_flags & O_NONBLOCK);
if (ret < 0)
- return ret;
+ goto error_out;
buf = alloc_buf(port->out_vq, 0, pipe->nrbufs);
- if (!buf)
- return -ENOMEM;
+ if (!buf) {
+ ret = -ENOMEM;
+ goto error_out;
+ }
sgl.n = 0;
sgl.len = 0;
@@ -946,12 +965,17 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe,
sgl.sg = buf->sg;
sg_init_table(sgl.sg, sgl.size);
ret = __splice_from_pipe(pipe, &sd, pipe_to_sg);
+ pipe_unlock(pipe);
if (likely(ret > 0))
ret = __send_to_port(port, buf->sg, sgl.n, sgl.len, buf, true);
if (unlikely(ret <= 0))
free_buf(buf, true);
return ret;
+
+error_out:
+ pipe_unlock(pipe);
+ return ret;
}
static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
@@ -1019,14 +1043,14 @@ static int port_fops_open(struct inode *inode, struct file *filp)
struct port *port;
int ret;
+ /* We get the port with a kref here */
port = find_port_by_devt(cdev->dev);
+ if (!port) {
+ /* Port was unplugged before we could proceed */
+ return -ENXIO;
+ }
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
@@ -1498,14 +1522,6 @@ static void remove_port(struct kref *kref)
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);
}
@@ -1539,12 +1555,14 @@ static void unplug_port(struct port *port)
spin_unlock_irq(&port->portdev->ports_lock);
if (port->guest_connected) {
+ /* Let the app know the port is going down. */
+ send_sigio_to_port(port);
+
+ /* Do this after sigio is actually sent */
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);
+ wake_up_interruptible(&port->waitqueue);
}
if (is_console_port(port)) {
@@ -1563,6 +1581,14 @@ static void unplug_port(struct port *port)
*/
port->portdev = NULL;
+ 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);
+
/*
* Locks around here are not necessary - a port can't be
* opened after we removed the port struct from ports_list
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 2168258fb2c3..74b88efde6ad 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -751,7 +751,7 @@ static void __virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity)
vscsi->affinity_hint_set = true;
} else {
- for (i = 0; i < vscsi->num_queues - VIRTIO_SCSI_VQ_BASE; i++)
+ for (i = 0; i < vscsi->num_queues; i++)
virtqueue_set_affinity(vscsi->req_vqs[i].vq, -1);
vscsi->affinity_hint_set = false;