diff options
author | Rusty Russell <rusty@rustcorp.com.au> | 2008-02-04 23:50:03 -0500 |
---|---|---|
committer | Rusty Russell <rusty@rustcorp.com.au> | 2008-02-04 07:50:03 -0500 |
commit | 6e5aa7efb27aec7e55b6463fa2c8db594c4226fa (patch) | |
tree | 060a955e711ac224136157a5410e88dcdab965af /drivers/block/virtio_blk.c | |
parent | b3369c1fb410fddeb38a404316c861395f6d6ae8 (diff) |
virtio: reset function
A reset function solves three problems:
1) It allows us to renegotiate features, eg. if we want to upgrade a
guest driver without rebooting the guest.
2) It gives us a clean way of shutting down virtqueues: after a reset,
we know that the buffers won't be used by the host, and
3) It helps the guest recover from messed-up drivers.
So we remove the ->shutdown hook, and the only way we now remove
feature bits is via reset.
We leave it to the driver to do the reset before it deletes queues:
the balloon driver, for example, needs to chat to the host in its
remove function.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'drivers/block/virtio_blk.c')
-rw-r--r-- | drivers/block/virtio_blk.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 54a8017ad487..6143337527e7 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c | |||
@@ -264,12 +264,16 @@ static void virtblk_remove(struct virtio_device *vdev) | |||
264 | struct virtio_blk *vblk = vdev->priv; | 264 | struct virtio_blk *vblk = vdev->priv; |
265 | int major = vblk->disk->major; | 265 | int major = vblk->disk->major; |
266 | 266 | ||
267 | /* Nothing should be pending. */ | ||
267 | BUG_ON(!list_empty(&vblk->reqs)); | 268 | BUG_ON(!list_empty(&vblk->reqs)); |
269 | |||
270 | /* Stop all the virtqueues. */ | ||
271 | vdev->config->reset(vdev); | ||
272 | |||
268 | blk_cleanup_queue(vblk->disk->queue); | 273 | blk_cleanup_queue(vblk->disk->queue); |
269 | put_disk(vblk->disk); | 274 | put_disk(vblk->disk); |
270 | unregister_blkdev(major, "virtblk"); | 275 | unregister_blkdev(major, "virtblk"); |
271 | mempool_destroy(vblk->pool); | 276 | mempool_destroy(vblk->pool); |
272 | /* There should be nothing in the queue now, so no need to shutdown */ | ||
273 | vdev->config->del_vq(vblk->vq); | 277 | vdev->config->del_vq(vblk->vq); |
274 | kfree(vblk); | 278 | kfree(vblk); |
275 | } | 279 | } |