vhost: Remove vhost_backend_can_merge() callback

Checking whether the memory regions are equal is sufficient: if they are
equal, then most certainly the contained fd is equal.

The whole vhost-user memslot handling is suboptimal and overly
complicated. We shouldn't have to lookup a RAM memory regions we got
notified about in vhost_user_get_mr_data() using a host pointer. But that
requires a bigger rework -- especially an alternative vhost_set_mem_table()
backend call that simply consumes MemoryRegionSections.

For now, let's just drop vhost_backend_can_merge().

Message-ID: <20230926185738.277351-3-david@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
This commit is contained in:
David Hildenbrand 2023-09-26 20:57:22 +02:00
parent 552b25229c
commit 309ebfa691
4 changed files with 1 additions and 24 deletions

View file

@ -728,11 +728,7 @@ static void vhost_region_add_section(struct vhost_dev *dev,
size_t offset = mrs_gpa - prev_gpa_start;
if (prev_host_start + offset == mrs_host &&
section->mr == prev_sec->mr &&
(!dev->vhost_ops->vhost_backend_can_merge ||
dev->vhost_ops->vhost_backend_can_merge(dev,
mrs_host, mrs_size,
prev_host_start, prev_size))) {
section->mr == prev_sec->mr) {
uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size);
need_add = false;
prev_sec->offset_within_address_space =