qemu-kvm/kvm-virtio-iommu-Rework-the-traces-in-virtio_iommu_set_p.patch

From 643d93343759a350fe0f6327d308bf6a93c79d25 Mon Sep 17 00:00:00 2001
From: Eric Auger <eric.auger@redhat.com>
Date: Wed, 5 Jul 2023 18:51:18 +0200
Subject: [PATCH 02/37] virtio-iommu: Rework the traces in
 virtio_iommu_set_page_size_mask()

RH-Author: Eric Auger <eric.auger@redhat.com>
RH-MergeRequest: 182: VIRTIO-IOMMU/VFIO page size related fixes
RH-Bugzilla: 2211609 2211634
RH-Acked-by: Gavin Shan <gshan@redhat.com>
RH-Acked-by: Sebastian Ott <None>
RH-Commit: [2/2] 0af7078dde158f07c83e2b293adc5d9d475688ae (eauger1/centos-qemu-kvm)

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2211609

The current error messages in virtio_iommu_set_page_size_mask()
sound quite similar for different situations and miss the IOMMU
memory region that causes the issue.

Clarify them and rework the comment.

Also remove the trace when the new page_size_mask is not applied as
the current frozen granule is kept. This message is rather confusing
for the end user and anyway the current granule would have been used
by the driver.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Message-Id: <20230705165118.28194-3-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Tested-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
(cherry picked from commit 587a7641d53055054d68d67d94c9408ef808f127)
Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 hw/virtio/virtio-iommu.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 542679b321..421e2a944f 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -1101,29 +1101,24 @@ static int virtio_iommu_set_page_size_mask(IOMMUMemoryRegion *mr,
                                           new_mask);
 
     if ((cur_mask & new_mask) == 0) {
-        error_setg(errp, "virtio-iommu page mask 0x%"PRIx64
-                   " is incompatible with mask 0x%"PRIx64, cur_mask, new_mask);
+        error_setg(errp, "virtio-iommu %s reports a page size mask 0x%"PRIx64
+                   " incompatible with currently supported mask 0x%"PRIx64,
+                   mr->parent_obj.name, new_mask, cur_mask);
         return -1;
     }
 
     /*
      * Once the granule is frozen we can't change the mask anymore. If by
      * chance the hotplugged device supports the same granule, we can still
-     * accept it. Having a different masks is possible but the guest will use
-     * sub-optimal block sizes, so warn about it.
+     * accept it.
      */
     if (s->granule_frozen) {
-        int new_granule = ctz64(new_mask);
         int cur_granule = ctz64(cur_mask);
 
-        if (new_granule != cur_granule) {
-            error_setg(errp, "virtio-iommu page mask 0x%"PRIx64
-                       " is incompatible with mask 0x%"PRIx64, cur_mask,
-                       new_mask);
+        if (!(BIT(cur_granule) & new_mask)) {
+            error_setg(errp, "virtio-iommu %s does not support frozen granule 0x%llx",
+                       mr->parent_obj.name, BIT_ULL(cur_granule));
             return -1;
-        } else if (new_mask != cur_mask) {
-            warn_report("virtio-iommu page mask 0x%"PRIx64
-                        " does not match 0x%"PRIx64, cur_mask, new_mask);
         }
         return 0;
     }
-- 
2.39.3