diff options
Diffstat (limited to 'drivers/vhost/vhost.c')
| -rw-r--r-- | drivers/vhost/vhost.c | 85 |
1 files changed, 62 insertions, 23 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index e05557d5299..c579dcc9200 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -60,22 +60,25 @@ static int vhost_poll_wakeup(wait_queue_t *wait, unsigned mode, int sync, return 0; } +static void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn) +{ + INIT_LIST_HEAD(&work->node); + work->fn = fn; + init_waitqueue_head(&work->done); + work->flushing = 0; + work->queue_seq = work->done_seq = 0; +} + /* Init poll structure */ void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, unsigned long mask, struct vhost_dev *dev) { - struct vhost_work *work = &poll->work; - init_waitqueue_func_entry(&poll->wait, vhost_poll_wakeup); init_poll_funcptr(&poll->table, vhost_poll_func); poll->mask = mask; poll->dev = dev; - INIT_LIST_HEAD(&work->node); - work->fn = fn; - init_waitqueue_head(&work->done); - work->flushing = 0; - work->queue_seq = work->done_seq = 0; + vhost_work_init(&poll->work, fn); } /* Start polling a file. We add ourselves to file's wait queue. The caller must @@ -95,35 +98,38 @@ void vhost_poll_stop(struct vhost_poll *poll) remove_wait_queue(poll->wqh, &poll->wait); } -/* Flush any work that has been scheduled. When calling this, don't hold any - * locks that are also used by the callback. */ -void vhost_poll_flush(struct vhost_poll *poll) +static void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work) { - struct vhost_work *work = &poll->work; unsigned seq; int left; int flushing; - spin_lock_irq(&poll->dev->work_lock); + spin_lock_irq(&dev->work_lock); seq = work->queue_seq; work->flushing++; - spin_unlock_irq(&poll->dev->work_lock); + spin_unlock_irq(&dev->work_lock); wait_event(work->done, ({ - spin_lock_irq(&poll->dev->work_lock); + spin_lock_irq(&dev->work_lock); left = seq - work->done_seq <= 0; - spin_unlock_irq(&poll->dev->work_lock); + spin_unlock_irq(&dev->work_lock); left; })); - spin_lock_irq(&poll->dev->work_lock); + spin_lock_irq(&dev->work_lock); flushing = --work->flushing; - spin_unlock_irq(&poll->dev->work_lock); + spin_unlock_irq(&dev->work_lock); BUG_ON(flushing < 0); } -void vhost_poll_queue(struct vhost_poll *poll) +/* Flush any work that has been scheduled. When calling this, don't hold any + * locks that are also used by the callback. */ +void vhost_poll_flush(struct vhost_poll *poll) +{ + vhost_work_flush(poll->dev, &poll->work); +} + +static inline void vhost_work_queue(struct vhost_dev *dev, + struct vhost_work *work) { - struct vhost_dev *dev = poll->dev; - struct vhost_work *work = &poll->work; unsigned long flags; spin_lock_irqsave(&dev->work_lock, flags); @@ -135,6 +141,11 @@ void vhost_poll_queue(struct vhost_poll *poll) spin_unlock_irqrestore(&dev->work_lock, flags); } +void vhost_poll_queue(struct vhost_poll *poll) +{ + vhost_work_queue(poll->dev, &poll->work); +} + static void vhost_vq_reset(struct vhost_dev *dev, struct vhost_virtqueue *vq) { @@ -236,6 +247,29 @@ long vhost_dev_check_owner(struct vhost_dev *dev) return dev->mm == current->mm ? 0 : -EPERM; } +struct vhost_attach_cgroups_struct { + struct vhost_work work; + struct task_struct *owner; + int ret; +}; + +static void vhost_attach_cgroups_work(struct vhost_work *work) +{ + struct vhost_attach_cgroups_struct *s; + s = container_of(work, struct vhost_attach_cgroups_struct, work); + s->ret = cgroup_attach_task_all(s->owner, current); +} + +static int vhost_attach_cgroups(struct vhost_dev *dev) +{ + struct vhost_attach_cgroups_struct attach; + attach.owner = current; + vhost_work_init(&attach.work, vhost_attach_cgroups_work); + vhost_work_queue(dev, &attach.work); + vhost_work_flush(dev, &attach.work); + return attach.ret; +} + /* Caller should have device mutex */ static long vhost_dev_set_owner(struct vhost_dev *dev) { @@ -255,14 +289,16 @@ static long vhost_dev_set_owner(struct vhost_dev *dev) } dev->worker = worker; - err = cgroup_attach_task_current_cg(worker); + wake_up_process(worker); /* avoid contributing to loadavg */ + + err = vhost_attach_cgroups(dev); if (err) goto err_cgroup; - wake_up_process(worker); /* avoid contributing to loadavg */ return 0; err_cgroup: kthread_stop(worker); + dev->worker = NULL; err_worker: if (dev->mm) mmput(dev->mm); @@ -323,7 +359,10 @@ void vhost_dev_cleanup(struct vhost_dev *dev) dev->mm = NULL; WARN_ON(!list_empty(&dev->work_list)); - kthread_stop(dev->worker); + if (dev->worker) { + kthread_stop(dev->worker); + dev->worker = NULL; + } } static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz) |