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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2015-02-10 11:35:36 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2015-02-10 11:35:36 -0800
commit4ba24fef3eb3b142197135223b90ced2f319cd53 (patch)
treea20c125b27740ec7b4c761b11d801108e1b316b2 /drivers/virtio/virtio.c
parent47c1ffb2b6b630894e9a16442611c056ab21c057 (diff)
parent98a4a59ee31a12105a2b84f5b8b515ac2cb208ef (diff)
Merge branch 'next' into for-linus
Prepare first round of input updates for 3.20.
Diffstat (limited to 'drivers/virtio/virtio.c')
-rw-r--r--drivers/virtio/virtio.c200
1 files changed, 183 insertions, 17 deletions
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index fed0ce198ae..b9f70dfc475 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -3,6 +3,7 @@
#include <linux/virtio_config.h>
#include <linux/module.h>
#include <linux/idr.h>
+#include <uapi/linux/virtio_ids.h>
/* Unique numbering for virtio devices. */
static DEFINE_IDA(virtio_index_ida);
@@ -49,9 +50,9 @@ static ssize_t features_show(struct device *_d,
/* We actually represent this as a bitstring, as it could be
* arbitrary length in future. */
- for (i = 0; i < ARRAY_SIZE(dev->features)*BITS_PER_LONG; i++)
+ for (i = 0; i < sizeof(dev->features)*8; i++)
len += sprintf(buf+len, "%c",
- test_bit(i, dev->features) ? '1' : '0');
+ __virtio_test_bit(dev, i) ? '1' : '0');
len += sprintf(buf+len, "\n");
return len;
}
@@ -113,16 +114,83 @@ void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
for (i = 0; i < drv->feature_table_size; i++)
if (drv->feature_table[i] == fbit)
return;
+
+ if (drv->feature_table_legacy) {
+ for (i = 0; i < drv->feature_table_size_legacy; i++)
+ if (drv->feature_table_legacy[i] == fbit)
+ return;
+ }
+
BUG();
}
EXPORT_SYMBOL_GPL(virtio_check_driver_offered_feature);
+static void __virtio_config_changed(struct virtio_device *dev)
+{
+ struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+
+ if (!dev->config_enabled)
+ dev->config_change_pending = true;
+ else if (drv && drv->config_changed)
+ drv->config_changed(dev);
+}
+
+void virtio_config_changed(struct virtio_device *dev)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->config_lock, flags);
+ __virtio_config_changed(dev);
+ spin_unlock_irqrestore(&dev->config_lock, flags);
+}
+EXPORT_SYMBOL_GPL(virtio_config_changed);
+
+static void virtio_config_disable(struct virtio_device *dev)
+{
+ spin_lock_irq(&dev->config_lock);
+ dev->config_enabled = false;
+ spin_unlock_irq(&dev->config_lock);
+}
+
+static void virtio_config_enable(struct virtio_device *dev)
+{
+ spin_lock_irq(&dev->config_lock);
+ dev->config_enabled = true;
+ if (dev->config_change_pending)
+ __virtio_config_changed(dev);
+ dev->config_change_pending = false;
+ spin_unlock_irq(&dev->config_lock);
+}
+
+static int virtio_finalize_features(struct virtio_device *dev)
+{
+ int ret = dev->config->finalize_features(dev);
+ unsigned status;
+
+ if (ret)
+ return ret;
+
+ if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1))
+ return 0;
+
+ add_status(dev, VIRTIO_CONFIG_S_FEATURES_OK);
+ status = dev->config->get_status(dev);
+ if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) {
+ dev_err(&dev->dev, "virtio: device refuses features: %x\n",
+ status);
+ return -ENODEV;
+ }
+ return 0;
+}
+
static int virtio_dev_probe(struct device *_d)
{
int err, i;
struct virtio_device *dev = dev_to_virtio(_d);
struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
- u32 device_features;
+ u64 device_features;
+ u64 driver_features;
+ u64 driver_features_legacy;
/* We have a driver! */
add_status(dev, VIRTIO_CONFIG_S_DRIVER);
@@ -130,32 +198,55 @@ static int virtio_dev_probe(struct device *_d)
/* Figure out what features the device supports. */
device_features = dev->config->get_features(dev);
- /* Features supported by both device and driver into dev->features. */
- memset(dev->features, 0, sizeof(dev->features));
+ /* Figure out what features the driver supports. */
+ driver_features = 0;
for (i = 0; i < drv->feature_table_size; i++) {
unsigned int f = drv->feature_table[i];
- BUG_ON(f >= 32);
- if (device_features & (1 << f))
- set_bit(f, dev->features);
+ BUG_ON(f >= 64);
+ driver_features |= (1ULL << f);
+ }
+
+ /* Some drivers have a separate feature table for virtio v1.0 */
+ if (drv->feature_table_legacy) {
+ driver_features_legacy = 0;
+ for (i = 0; i < drv->feature_table_size_legacy; i++) {
+ unsigned int f = drv->feature_table_legacy[i];
+ BUG_ON(f >= 64);
+ driver_features_legacy |= (1ULL << f);
+ }
+ } else {
+ driver_features_legacy = driver_features;
}
+ if (device_features & (1ULL << VIRTIO_F_VERSION_1))
+ dev->features = driver_features & device_features;
+ else
+ dev->features = driver_features_legacy & device_features;
+
/* Transport features always preserved to pass to finalize_features. */
for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++)
- if (device_features & (1 << i))
- set_bit(i, dev->features);
+ if (device_features & (1ULL << i))
+ __virtio_set_bit(dev, i);
- dev->config->finalize_features(dev);
+ err = virtio_finalize_features(dev);
+ if (err)
+ goto err;
err = drv->probe(dev);
if (err)
- add_status(dev, VIRTIO_CONFIG_S_FAILED);
- else {
- add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
- if (drv->scan)
- drv->scan(dev);
- }
+ goto err;
+
+ add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
+ if (drv->scan)
+ drv->scan(dev);
+ virtio_config_enable(dev);
+
+ return 0;
+err:
+ add_status(dev, VIRTIO_CONFIG_S_FAILED);
return err;
+
}
static int virtio_dev_remove(struct device *_d)
@@ -163,6 +254,8 @@ static int virtio_dev_remove(struct device *_d)
struct virtio_device *dev = dev_to_virtio(_d);
struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+ virtio_config_disable(dev);
+
drv->remove(dev);
/* Driver should have reset device. */
@@ -182,6 +275,12 @@ static struct bus_type virtio_bus = {
.remove = virtio_dev_remove,
};
+bool virtio_device_is_legacy_only(struct virtio_device_id id)
+{
+ return id.device == VIRTIO_ID_BALLOON;
+}
+EXPORT_SYMBOL_GPL(virtio_device_is_legacy_only);
+
int register_virtio_driver(struct virtio_driver *driver)
{
/* Catch this early. */
@@ -211,6 +310,10 @@ int register_virtio_device(struct virtio_device *dev)
dev->index = err;
dev_set_name(&dev->dev, "virtio%u", dev->index);
+ spin_lock_init(&dev->config_lock);
+ dev->config_enabled = false;
+ dev->config_change_pending = false;
+
/* We always start by resetting the device, in case a previous
* driver messed it up. This also tests that code path a little. */
dev->config->reset(dev);
@@ -239,6 +342,69 @@ void unregister_virtio_device(struct virtio_device *dev)
}
EXPORT_SYMBOL_GPL(unregister_virtio_device);
+#ifdef CONFIG_PM_SLEEP
+int virtio_device_freeze(struct virtio_device *dev)
+{
+ struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+
+ virtio_config_disable(dev);
+
+ dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
+
+ if (drv && drv->freeze)
+ return drv->freeze(dev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_device_freeze);
+
+int virtio_device_restore(struct virtio_device *dev)
+{
+ struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+ int ret;
+
+ /* We always start by resetting the device, in case a previous
+ * driver messed it up. */
+ dev->config->reset(dev);
+
+ /* Acknowledge that we've seen the device. */
+ add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+
+ /* Maybe driver failed before freeze.
+ * Restore the failed status, for debugging. */
+ if (dev->failed)
+ add_status(dev, VIRTIO_CONFIG_S_FAILED);
+
+ if (!drv)
+ return 0;
+
+ /* We have a driver! */
+ add_status(dev, VIRTIO_CONFIG_S_DRIVER);
+
+ ret = virtio_finalize_features(dev);
+ if (ret)
+ goto err;
+
+ if (drv->restore) {
+ ret = drv->restore(dev);
+ if (ret)
+ goto err;
+ }
+
+ /* Finally, tell the device we're all set */
+ add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
+
+ virtio_config_enable(dev);
+
+ return 0;
+
+err:
+ add_status(dev, VIRTIO_CONFIG_S_FAILED);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(virtio_device_restore);
+#endif
+
static int virtio_init(void)
{
if (bus_register(&virtio_bus) != 0)