From: Patrick Fu <patrick.fu@intel.com>
Date: Tue, 27 Oct 2020 02:06:08 +0000 (+0800)
Subject: vhost: fix guest/host physical address conversion
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=fb4b7a131c9ea45fa6381c7492d7568c302d3cc2;p=dpdk.git

vhost: fix guest/host physical address conversion

gpa_to_hpa() function almost always fails due to the wrong setup of
the binary tree search key. Since there has already been a similar
function gpa_to_first_hpa() available in the vhost, instead of fixing
the issue in its original logic, gpa_to_hpa() function is rewritten to
be a wrapper of the gpa_to_first_hpa() to avoid code redundancy.

Fixes: e246896178e6 ("vhost: get guest/host physical address mappings")
Fixes: faa9867c4da2 ("vhost: use binary search in address conversion")
Cc: stable@dpdk.org

Signed-off-by: Patrick Fu <patrick.fu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 75d79f80a7..361c9f79b3 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -563,38 +563,6 @@ static __rte_always_inline int guest_page_addrcmp(const void *p1,
 	return 0;
 }
 
-/* Convert guest physical address to host physical address */
-static __rte_always_inline rte_iova_t
-gpa_to_hpa(struct virtio_net *dev, uint64_t gpa, uint64_t size)
-{
-	uint32_t i;
-	struct guest_page *page;
-	struct guest_page key;
-
-	if (dev->nr_guest_pages >= VHOST_BINARY_SEARCH_THRESH) {
-		key.guest_phys_addr = gpa;
-		page = bsearch(&key, dev->guest_pages, dev->nr_guest_pages,
-			       sizeof(struct guest_page), guest_page_addrcmp);
-		if (page) {
-			if (gpa + size < page->guest_phys_addr + page->size)
-				return gpa - page->guest_phys_addr +
-					page->host_phys_addr;
-		}
-	} else {
-		for (i = 0; i < dev->nr_guest_pages; i++) {
-			page = &dev->guest_pages[i];
-
-			if (gpa >= page->guest_phys_addr &&
-			    gpa + size < page->guest_phys_addr +
-			    page->size)
-				return gpa - page->guest_phys_addr +
-				       page->host_phys_addr;
-		}
-	}
-
-	return 0;
-}
-
 static __rte_always_inline rte_iova_t
 gpa_to_first_hpa(struct virtio_net *dev, uint64_t gpa,
 	uint64_t gpa_size, uint64_t *hpa_size)
@@ -645,6 +613,17 @@ gpa_to_first_hpa(struct virtio_net *dev, uint64_t gpa,
 	return 0;
 }
 
+/* Convert guest physical address to host physical address */
+static __rte_always_inline rte_iova_t
+gpa_to_hpa(struct virtio_net *dev, uint64_t gpa, uint64_t size)
+{
+	rte_iova_t hpa;
+	uint64_t hpa_size;
+
+	hpa = gpa_to_first_hpa(dev, gpa, size, &hpa_size);
+	return hpa_size == size ? hpa : 0;
+}
+
 static __rte_always_inline uint64_t
 hva_to_gpa(struct virtio_net *dev, uint64_t vva, uint64_t len)
 {