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Diffstat (limited to 'drivers/virtio/virtio.c')
-rw-r--r--drivers/virtio/virtio.c65
1 files changed, 18 insertions, 47 deletions
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 69d7ea02cd48..b535483bc556 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -102,9 +102,13 @@ static int virtio_dev_remove(struct device *_d)
102 struct virtio_driver *drv = container_of(dev->dev.driver, 102 struct virtio_driver *drv = container_of(dev->dev.driver,
103 struct virtio_driver, driver); 103 struct virtio_driver, driver);
104 104
105 dev->config->set_status(dev, dev->config->get_status(dev)
106 & ~VIRTIO_CONFIG_S_DRIVER);
107 drv->remove(dev); 105 drv->remove(dev);
106
107 /* Driver should have reset device. */
108 BUG_ON(dev->config->get_status(dev));
109
110 /* Acknowledge the device's existence again. */
111 add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
108 return 0; 112 return 0;
109} 113}
110 114
@@ -130,6 +134,10 @@ int register_virtio_device(struct virtio_device *dev)
130 dev->dev.bus = &virtio_bus; 134 dev->dev.bus = &virtio_bus;
131 sprintf(dev->dev.bus_id, "%u", dev->index); 135 sprintf(dev->dev.bus_id, "%u", dev->index);
132 136
137 /* We always start by resetting the device, in case a previous
138 * driver messed it up. This also tests that code path a little. */
139 dev->config->reset(dev);
140
133 /* Acknowledge that we've seen the device. */ 141 /* Acknowledge that we've seen the device. */
134 add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE); 142 add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
135 143
@@ -148,55 +156,18 @@ void unregister_virtio_device(struct virtio_device *dev)
148} 156}
149EXPORT_SYMBOL_GPL(unregister_virtio_device); 157EXPORT_SYMBOL_GPL(unregister_virtio_device);
150 158
151int __virtio_config_val(struct virtio_device *vdev,
152 u8 type, void *val, size_t size)
153{
154 void *token;
155 unsigned int len;
156
157 token = vdev->config->find(vdev, type, &len);
158 if (!token)
159 return -ENOENT;
160
161 if (len != size)
162 return -EIO;
163
164 vdev->config->get(vdev, token, val, size);
165 return 0;
166}
167EXPORT_SYMBOL_GPL(__virtio_config_val);
168
169int virtio_use_bit(struct virtio_device *vdev,
170 void *token, unsigned int len, unsigned int bitnum)
171{
172 unsigned long bits[16];
173
174 /* This makes it convenient to pass-through find() results. */
175 if (!token)
176 return 0;
177
178 /* bit not in range of this bitfield? */
179 if (bitnum * 8 >= len / 2)
180 return 0;
181
182 /* Giant feature bitfields are silly. */
183 BUG_ON(len > sizeof(bits));
184 vdev->config->get(vdev, token, bits, len);
185
186 if (!test_bit(bitnum, bits))
187 return 0;
188
189 /* Set acknowledge bit, and write it back. */
190 set_bit(bitnum + len * 8 / 2, bits);
191 vdev->config->set(vdev, token, bits, len);
192 return 1;
193}
194EXPORT_SYMBOL_GPL(virtio_use_bit);
195
196static int virtio_init(void) 159static int virtio_init(void)
197{ 160{
198 if (bus_register(&virtio_bus) != 0) 161 if (bus_register(&virtio_bus) != 0)
199 panic("virtio bus registration failed"); 162 panic("virtio bus registration failed");
200 return 0; 163 return 0;
201} 164}
165
166static void __exit virtio_exit(void)
167{
168 bus_unregister(&virtio_bus);
169}
202core_initcall(virtio_init); 170core_initcall(virtio_init);
171module_exit(virtio_exit);
172
173MODULE_LICENSE("GPL");