From 4084168a694381238dadf1f5c0cc4af756ac883f Mon Sep 17 00:00:00 2001
From: Peter Xu <peterx@redhat.com>
Date: Thu, 8 Nov 2018 06:29:37 +0000
Subject: [PATCH 09/35] intel_iommu: move ce fetching out when sync shadow

RH-Author: Peter Xu <peterx@redhat.com>
Message-id: <20181108062938.21143-7-peterx@redhat.com>
Patchwork-id: 82965
O-Subject: [RHEL-8 qemu-kvm PATCH 6/7] intel_iommu: move ce fetching out when sync shadow
Bugzilla: 1625173
RH-Acked-by: Auger Eric <eric.auger@redhat.com>
RH-Acked-by: Michael S. Tsirkin <mst@redhat.com>
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>

Bugzilla: 1629616

There are two callers for vtd_sync_shadow_page_table_range(): one
provided a valid context entry and one not.  Move that fetching
operation into the caller vtd_sync_shadow_page_table() where we need to
fetch the context entry.

Meanwhile, remove the error_report_once() directly since we're already
tracing all the error cases in the previous call.  Instead, return error
number back to caller.  This will not change anything functional since
callers are dropping it after all.

We do this move majorly because we want to do something more later in
vtd_sync_shadow_page_table().

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 95ecd3df7815b4bc4f9a0f47e1c64d81434715aa)
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
 hw/i386/intel_iommu.c | 41 +++++++++++++----------------------------
 1 file changed, 13 insertions(+), 28 deletions(-)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index a6e87a9..c95128d 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -1045,7 +1045,6 @@ static int vtd_sync_shadow_page_hook(IOMMUTLBEntry *entry,
     return 0;
 }
 
-/* If context entry is NULL, we'll try to fetch it on our own. */
 static int vtd_sync_shadow_page_table_range(VTDAddressSpace *vtd_as,
                                             VTDContextEntry *ce,
                                             hwaddr addr, hwaddr size)
@@ -1057,39 +1056,25 @@ static int vtd_sync_shadow_page_table_range(VTDAddressSpace *vtd_as,
         .notify_unmap = true,
         .aw = s->aw_bits,
         .as = vtd_as,
+        .domain_id = VTD_CONTEXT_ENTRY_DID(ce->hi),
     };
-    VTDContextEntry ce_cache;
-    int ret;
-
-    if (ce) {
-        /* If the caller provided context entry, use it */
-        ce_cache = *ce;
-    } else {
-        /* If the caller didn't provide ce, try to fetch */
-        ret = vtd_dev_to_context_entry(s, pci_bus_num(vtd_as->bus),
-                                       vtd_as->devfn, &ce_cache);
-        if (ret) {
-            /*
-             * This should not really happen, but in case it happens,
-             * we just skip the sync for this time.  After all we even
-             * don't have the root table pointer!
-             */
-            error_report_once("%s: invalid context entry for bus 0x%x"
-                              " devfn 0x%x",
-                              __func__, pci_bus_num(vtd_as->bus),
-                              vtd_as->devfn);
-            return 0;
-        }
-    }
 
-    info.domain_id = VTD_CONTEXT_ENTRY_DID(ce_cache.hi);
-
-    return vtd_page_walk(&ce_cache, addr, addr + size, &info);
+    return vtd_page_walk(ce, addr, addr + size, &info);
 }
 
 static int vtd_sync_shadow_page_table(VTDAddressSpace *vtd_as)
 {
-    return vtd_sync_shadow_page_table_range(vtd_as, NULL, 0, UINT64_MAX);
+    int ret;
+    VTDContextEntry ce;
+
+    ret = vtd_dev_to_context_entry(vtd_as->iommu_state,
+                                   pci_bus_num(vtd_as->bus),
+                                   vtd_as->devfn, &ce);
+    if (ret) {
+        return ret;
+    }
+
+    return vtd_sync_shadow_page_table_range(vtd_as, &ce, 0, UINT64_MAX);
 }
 
 /*
-- 
1.8.3.1