From f53d9910d009bc015b42d88114e2d86a93b0e6b7 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Mon, 15 Mar 2021 17:34:38 +0100 Subject: vringh: add 'iotlb_lock' to synchronize iotlb accesses Usually iotlb accesses are synchronized with a spinlock. Let's request it as a new parameter in vringh_set_iotlb() and hold it when we navigate the iotlb in iotlb_translate() to avoid race conditions with any new additions/deletions of ranges from the ioltb. Acked-by: Jason Wang Signed-off-by: Stefano Garzarella Link: https://lore.kernel.org/r/20210315163450.254396-3-sgarzare@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vringh.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'drivers/vhost/vringh.c') diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c index 85d85faba058..f68122705719 100644 --- a/drivers/vhost/vringh.c +++ b/drivers/vhost/vringh.c @@ -1074,6 +1074,8 @@ static int iotlb_translate(const struct vringh *vrh, int ret = 0; u64 s = 0; + spin_lock(vrh->iotlb_lock); + while (len > s) { u64 size, pa, pfn; @@ -1103,6 +1105,8 @@ static int iotlb_translate(const struct vringh *vrh, ++ret; } + spin_unlock(vrh->iotlb_lock); + return ret; } @@ -1262,10 +1266,13 @@ EXPORT_SYMBOL(vringh_init_iotlb); * vringh_set_iotlb - initialize a vringh for a ring with IOTLB. * @vrh: the vring * @iotlb: iotlb associated with this vring + * @iotlb_lock: spinlock to synchronize the iotlb accesses */ -void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb) +void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, + spinlock_t *iotlb_lock) { vrh->iotlb = iotlb; + vrh->iotlb_lock = iotlb_lock; } EXPORT_SYMBOL(vringh_set_iotlb); -- cgit v1.2.3