vfio: add local lock for virqfd instead of depending on VFIO PCI
The Virqfd code needs to keep accesses to any struct *virqfd safe, but this comes into play only when creating or destroying eventfds, so sharing the same spinlock with the VFIO bus driver is not necessary. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
parent
bb78e9eaab
commit
9269c393e7
|
@ -44,6 +44,7 @@ struct virqfd {
|
|||
};
|
||||
|
||||
static struct workqueue_struct *vfio_irqfd_cleanup_wq;
|
||||
DEFINE_SPINLOCK(virqfd_lock);
|
||||
|
||||
int __init vfio_virqfd_init(void)
|
||||
{
|
||||
|
@ -80,21 +81,21 @@ static int virqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
|
|||
|
||||
if (flags & POLLHUP) {
|
||||
unsigned long flags;
|
||||
spin_lock_irqsave(&virqfd->vdev->irqlock, flags);
|
||||
spin_lock_irqsave(&virqfd_lock, flags);
|
||||
|
||||
/*
|
||||
* The eventfd is closing, if the virqfd has not yet been
|
||||
* queued for release, as determined by testing whether the
|
||||
* vdev pointer to it is still valid, queue it now. As
|
||||
* virqfd pointer to it is still valid, queue it now. As
|
||||
* with kvm irqfds, we know we won't race against the virqfd
|
||||
* going away because we hold wqh->lock to get here.
|
||||
* going away because we hold the lock to get here.
|
||||
*/
|
||||
if (*(virqfd->pvirqfd) == virqfd) {
|
||||
*(virqfd->pvirqfd) = NULL;
|
||||
virqfd_deactivate(virqfd);
|
||||
}
|
||||
|
||||
spin_unlock_irqrestore(&virqfd->vdev->irqlock, flags);
|
||||
spin_unlock_irqrestore(&virqfd_lock, flags);
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
@ -170,16 +171,16 @@ int vfio_virqfd_enable(struct vfio_pci_device *vdev,
|
|||
* we update the pointer to the virqfd under lock to avoid
|
||||
* pushing multiple jobs to release the same virqfd.
|
||||
*/
|
||||
spin_lock_irq(&vdev->irqlock);
|
||||
spin_lock_irq(&virqfd_lock);
|
||||
|
||||
if (*pvirqfd) {
|
||||
spin_unlock_irq(&vdev->irqlock);
|
||||
spin_unlock_irq(&virqfd_lock);
|
||||
ret = -EBUSY;
|
||||
goto err_busy;
|
||||
}
|
||||
*pvirqfd = virqfd;
|
||||
|
||||
spin_unlock_irq(&vdev->irqlock);
|
||||
spin_unlock_irq(&virqfd_lock);
|
||||
|
||||
/*
|
||||
* Install our own custom wake-up handling so we are notified via
|
||||
|
@ -217,18 +218,18 @@ err_fd:
|
|||
}
|
||||
EXPORT_SYMBOL_GPL(vfio_virqfd_enable);
|
||||
|
||||
void vfio_virqfd_disable(struct vfio_pci_device *vdev, struct virqfd **pvirqfd)
|
||||
void vfio_virqfd_disable(struct virqfd **pvirqfd)
|
||||
{
|
||||
unsigned long flags;
|
||||
|
||||
spin_lock_irqsave(&vdev->irqlock, flags);
|
||||
spin_lock_irqsave(&virqfd_lock, flags);
|
||||
|
||||
if (*pvirqfd) {
|
||||
virqfd_deactivate(*pvirqfd);
|
||||
*pvirqfd = NULL;
|
||||
}
|
||||
|
||||
spin_unlock_irqrestore(&vdev->irqlock, flags);
|
||||
spin_unlock_irqrestore(&virqfd_lock, flags);
|
||||
|
||||
/*
|
||||
* Block until we know all outstanding shutdown jobs have completed.
|
||||
|
@ -441,8 +442,8 @@ static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd)
|
|||
static void vfio_intx_disable(struct vfio_pci_device *vdev)
|
||||
{
|
||||
vfio_intx_set_signal(vdev, -1);
|
||||
vfio_virqfd_disable(vdev, &vdev->ctx[0].unmask);
|
||||
vfio_virqfd_disable(vdev, &vdev->ctx[0].mask);
|
||||
vfio_virqfd_disable(&vdev->ctx[0].unmask);
|
||||
vfio_virqfd_disable(&vdev->ctx[0].mask);
|
||||
vdev->irq_type = VFIO_PCI_NUM_IRQS;
|
||||
vdev->num_ctx = 0;
|
||||
kfree(vdev->ctx);
|
||||
|
@ -606,8 +607,8 @@ static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix)
|
|||
vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
|
||||
|
||||
for (i = 0; i < vdev->num_ctx; i++) {
|
||||
vfio_virqfd_disable(vdev, &vdev->ctx[i].unmask);
|
||||
vfio_virqfd_disable(vdev, &vdev->ctx[i].mask);
|
||||
vfio_virqfd_disable(&vdev->ctx[i].unmask);
|
||||
vfio_virqfd_disable(&vdev->ctx[i].mask);
|
||||
}
|
||||
|
||||
if (msix) {
|
||||
|
@ -645,7 +646,7 @@ static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev,
|
|||
vfio_send_intx_eventfd, NULL,
|
||||
&vdev->ctx[0].unmask, fd);
|
||||
|
||||
vfio_virqfd_disable(vdev, &vdev->ctx[0].unmask);
|
||||
vfio_virqfd_disable(&vdev->ctx[0].unmask);
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
|
Loading…
Reference in a new issue