diff options
| -rw-r--r-- | Documentation/driver-api/uio-howto.rst | 4 | ||||
| -rw-r--r-- | drivers/uio/uio_hv_generic.c | 19 |
2 files changed, 23 insertions, 0 deletions
diff --git a/Documentation/driver-api/uio-howto.rst b/Documentation/driver-api/uio-howto.rst index 97e6435b3934..693e3bd84e79 100644 --- a/Documentation/driver-api/uio-howto.rst +++ b/Documentation/driver-api/uio-howto.rst @@ -698,6 +698,10 @@ prevents the device from generating further interrupts until the bit is cleared. The userspace driver should clear this bit before blocking and waiting for more interrupts. +When host rescinds a device, the interrupt file descriptor is marked down +and any reads of the interrupt file descriptor will return -EIO. Similar +to a closed socket or disconnected serial device. + The vmbus device regions are mapped into uio device resources: 0) Channel ring buffers: guest to host and host to guest 1) Guest to host interrupt signalling pages diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c index ee6d862ef4bd..8c6b04a26c47 100644 --- a/drivers/uio/uio_hv_generic.c +++ b/drivers/uio/uio_hv_generic.c @@ -103,6 +103,23 @@ static void hv_uio_channel_cb(void *context) uio_event_notify(&pdata->info); } +/* + * Callback from vmbus_event when channel is rescinded. + */ +static void hv_uio_rescind(struct vmbus_channel *channel) +{ + struct hv_device *hv_dev = channel->primary_channel->device_obj; + struct hv_uio_private_data *pdata = hv_get_drvdata(hv_dev); + + /* + * Turn off the interrupt file handle + * Next read for event will return -EIO + */ + pdata->info.irq = 0; + + /* Wake up reader */ + uio_event_notify(&pdata->info); +} static void hv_uio_cleanup(struct hv_device *dev, struct hv_uio_private_data *pdata) @@ -218,6 +235,8 @@ hv_uio_probe(struct hv_device *dev, goto fail_close; } + vmbus_set_chn_rescind_callback(dev->channel, hv_uio_rescind); + hv_set_drvdata(dev, pdata); return 0; |