[PATCH] iommu/amd-vi: adjust _amd_iommu_flush_pages() to handle pseudo-domids

[Roger Pau Monne]

When the passed domain is DomIO iterate over the list of DomIO
assigned devices and flush each pseudo-domid found.

invalidate_all_domain_pages() does call amd_iommu_flush_all_pages()
with DomIO as a parameter, and hence the underlying
_amd_iommu_flush_pages() implementation must be capable of flushing
all pseudo-domids used by the quarantine domain logic.

While there fix invalidate_all_domain_pages() to only attempt to flush
the domains that have IOMMU enabled, otherwise the flush is pointless.

Fixes: 14dd241aad8a ('IOMMU/x86: use per-device page tables for quarantining')
Signed-off-by: Roger Pau Monné <roger....@citrix.com>
---
Only build tested, as I don't have an AMD system that I can do
suspend/resume on.
---
 xen/drivers/passthrough/amd/iommu_cmd.c  | 29 ++++++++++++++++++++----
 xen/drivers/passthrough/amd/iommu_init.c |  4 +++-
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/xen/drivers/passthrough/amd/iommu_cmd.c 
b/xen/drivers/passthrough/amd/iommu_cmd.c
index 40ddf366bb4d..ff55e3b88ae6 100644
--- a/xen/drivers/passthrough/amd/iommu_cmd.c
+++ b/xen/drivers/passthrough/amd/iommu_cmd.c
@@ -330,13 +330,34 @@ static void _amd_iommu_flush_pages(struct domain *d,
                                    daddr_t daddr, unsigned int order)
 {
     struct amd_iommu *iommu;
-    unsigned int dom_id = d->domain_id;
 
     /* send INVALIDATE_IOMMU_PAGES command */
-    for_each_amd_iommu ( iommu )
+    if ( d != dom_io )
     {
-        invalidate_iommu_pages(iommu, daddr, dom_id, order);
-        flush_command_buffer(iommu, 0);
+        for_each_amd_iommu ( iommu )
+        {
+            invalidate_iommu_pages(iommu, daddr, d->domain_id, order);
+            flush_command_buffer(iommu, 0);
+        }
+    }
+    else
+    {
+        const struct pci_dev *pdev;
+
+        for_each_pdev(dom_io, pdev)
+            if ( pdev->arch.pseudo_domid != DOMID_INVALID )
+            {
+                iommu = find_iommu_for_device(pdev->sbdf.seg, pdev->sbdf.bdf);
+                if ( !iommu )
+                {
+                    ASSERT_UNREACHABLE();
+                    continue;
+                }
+
+                invalidate_iommu_pages(iommu, daddr, pdev->arch.pseudo_domid,
+                                       order);
+                flush_command_buffer(iommu, 0);
+            }
     }
 
     if ( ats_enabled )
diff --git a/xen/drivers/passthrough/amd/iommu_init.c 
b/xen/drivers/passthrough/amd/iommu_init.c
index 7dbd7e7d094a..af6713d2fc02 100644
--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -1532,8 +1532,10 @@ int __init amd_iommu_init_late(void)
 static void invalidate_all_domain_pages(void)
 {
     struct domain *d;
+
     for_each_domain( d )
-        amd_iommu_flush_all_pages(d);
+        if ( is_iommu_enabled(d) )
+            amd_iommu_flush_all_pages(d);
 }
 
 static int cf_check _invalidate_all_devices(
-- 
2.40.0