vhost: correctly set bits of dirty pages
Fix two bugs in dirty page logging:
When counting pages we should increase address by 1 instead of
VHOST_PAGE_SIZE. Make log_write() correctly process requests
that cross pages with write_address not starting at page boundary.
Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 916cdbc..4c256d1 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -885,6 +885,7 @@
int r;
if (!write_length)
return 0;
+ write_length += write_address % VHOST_PAGE_SIZE;
write_address /= VHOST_PAGE_SIZE;
for (;;) {
u64 base = (u64)(unsigned long)log_base;
@@ -898,7 +899,7 @@
if (write_length <= VHOST_PAGE_SIZE)
break;
write_length -= VHOST_PAGE_SIZE;
- write_address += VHOST_PAGE_SIZE;
+ write_address += 1;
}
return r;
}