Commit 90e03207f468e84258270ad07095ef50f925c17d
Committed by
Rusty Russell
Rusty Russell
1 parent
c877bab507
Exists in
smarc-l5.0.0_1.0.0-ga
and in
5 other branches
virtio: Use ida to allocate virtio index
Current index allocation in virtio is based on a monotonically
increasing variable "index". This means we'll run out of numbers
after a while. E.g. someone crazy doing this in host side.
while(1) {
hot-plug a virtio device
hot-unplug the virito devcie
}
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Showing 1 changed file with 9 additions and 2 deletions Side-by-side Diff
drivers/virtio/virtio.c
| ... | ... | @@ -2,9 +2,10 @@ |
| 2 | 2 | #include <linux/spinlock.h> |
| 3 | 3 | #include <linux/virtio_config.h> |
| 4 | 4 | #include <linux/module.h> |
| 5 | +#include <linux/idr.h> | |
| 5 | 6 | |
| 6 | 7 | /* Unique numbering for virtio devices. */ |
| 7 | -static unsigned int dev_index; | |
| 8 | +static DEFINE_IDA(virtio_index_ida); | |
| 8 | 9 | |
| 9 | 10 | static ssize_t device_show(struct device *_d, |
| 10 | 11 | struct device_attribute *attr, char *buf) |
| ... | ... | @@ -193,7 +194,11 @@ |
| 193 | 194 | dev->dev.bus = &virtio_bus; |
| 194 | 195 | |
| 195 | 196 | /* Assign a unique device index and hence name. */ |
| 196 | - dev->index = dev_index++; | |
| 197 | + err = ida_simple_get(&virtio_index_ida, 0, 0, GFP_KERNEL); | |
| 198 | + if (err < 0) | |
| 199 | + goto out; | |
| 200 | + | |
| 201 | + dev->index = err; | |
| 197 | 202 | dev_set_name(&dev->dev, "virtio%u", dev->index); |
| 198 | 203 | |
| 199 | 204 | /* We always start by resetting the device, in case a previous |
| ... | ... | @@ -208,6 +213,7 @@ |
| 208 | 213 | /* device_register() causes the bus infrastructure to look for a |
| 209 | 214 | * matching driver. */ |
| 210 | 215 | err = device_register(&dev->dev); |
| 216 | +out: | |
| 211 | 217 | if (err) |
| 212 | 218 | add_status(dev, VIRTIO_CONFIG_S_FAILED); |
| 213 | 219 | return err; |
| ... | ... | @@ -217,6 +223,7 @@ |
| 217 | 223 | void unregister_virtio_device(struct virtio_device *dev) |
| 218 | 224 | { |
| 219 | 225 | device_unregister(&dev->dev); |
| 226 | + ida_simple_remove(&virtio_index_ida, dev->index); | |
| 220 | 227 | } |
| 221 | 228 | EXPORT_SYMBOL_GPL(unregister_virtio_device); |
| 222 | 229 |