[PATCH v3 09/17] intel_iommu: Flush stage-1 cache in iotlb invalidation

Zhenzhong Duan posted 17 patches 2 months ago
There is a newer version of this series
[PATCH v3 09/17] intel_iommu: Flush stage-1 cache in iotlb invalidation
Posted by Zhenzhong Duan 2 months ago
According to spec, Page-Selective-within-Domain Invalidation (11b):

1. IOTLB entries caching second-stage mappings (PGTT=010b) or pass-through
(PGTT=100b) mappings associated with the specified domain-id and the
input-address range are invalidated.
2. IOTLB entries caching first-stage (PGTT=001b) or nested (PGTT=011b)
mapping associated with specified domain-id are invalidated.

So per spec definition the Page-Selective-within-Domain Invalidation
needs to flush first stage and nested cached IOTLB enties as well.

We don't support nested yet and pass-through mapping is never cached,
so what in iotlb cache are only first-stage and second-stage mappings.

Add a tag pgtt in VTDIOTLBEntry to mark PGTT type of the mapping and
invalidate entries based on PGTT type.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Clément Mathieu--Drif<clement.mathieu--drif@eviden.com>
---
 include/hw/i386/intel_iommu.h |  1 +
 hw/i386/intel_iommu.c         | 27 +++++++++++++++++++++------
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
index fe9057c50d..b843d069cc 100644
--- a/include/hw/i386/intel_iommu.h
+++ b/include/hw/i386/intel_iommu.h
@@ -155,6 +155,7 @@ struct VTDIOTLBEntry {
     uint64_t pte;
     uint64_t mask;
     uint8_t access_flags;
+    uint8_t pgtt;
 };
 
 /* VT-d Source-ID Qualifier types */
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 180505423d..0df3fe2b6f 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -305,9 +305,21 @@ static gboolean vtd_hash_remove_by_page(gpointer key, gpointer value,
     VTDIOTLBPageInvInfo *info = (VTDIOTLBPageInvInfo *)user_data;
     uint64_t gfn = (info->addr >> VTD_PAGE_SHIFT_4K) & info->mask;
     uint64_t gfn_tlb = (info->addr & entry->mask) >> VTD_PAGE_SHIFT_4K;
-    return (entry->domain_id == info->domain_id) &&
-            (((entry->gfn & info->mask) == gfn) ||
-             (entry->gfn == gfn_tlb));
+
+    if (entry->domain_id != info->domain_id) {
+        return false;
+    }
+
+    /*
+     * According to spec, IOTLB entries caching first-stage (PGTT=001b) or
+     * nested (PGTT=011b) mapping associated with specified domain-id are
+     * invalidated. Nested isn't supported yet, so only need to check 001b.
+     */
+    if (entry->pgtt == VTD_SM_PASID_ENTRY_FLT) {
+        return true;
+    }
+
+    return (entry->gfn & info->mask) == gfn || entry->gfn == gfn_tlb;
 }
 
 /* Reset all the gen of VTDAddressSpace to zero and set the gen of
@@ -382,7 +394,7 @@ out:
 static void vtd_update_iotlb(IntelIOMMUState *s, uint16_t source_id,
                              uint16_t domain_id, hwaddr addr, uint64_t pte,
                              uint8_t access_flags, uint32_t level,
-                             uint32_t pasid)
+                             uint32_t pasid, uint8_t pgtt)
 {
     VTDIOTLBEntry *entry = g_malloc(sizeof(*entry));
     struct vtd_iotlb_key *key = g_malloc(sizeof(*key));
@@ -400,6 +412,7 @@ static void vtd_update_iotlb(IntelIOMMUState *s, uint16_t source_id,
     entry->access_flags = access_flags;
     entry->mask = vtd_pt_level_page_mask(level);
     entry->pasid = pasid;
+    entry->pgtt = pgtt;
 
     key->gfn = gfn;
     key->sid = source_id;
@@ -2069,7 +2082,7 @@ static bool vtd_do_iommu_translate(VTDAddressSpace *vtd_as, PCIBus *bus,
     bool is_fpd_set = false;
     bool reads = true;
     bool writes = true;
-    uint8_t access_flags;
+    uint8_t access_flags, pgtt;
     bool rid2pasid = (pasid == PCI_NO_PASID) && s->root_scalable;
     VTDIOTLBEntry *iotlb_entry;
 
@@ -2177,9 +2190,11 @@ static bool vtd_do_iommu_translate(VTDAddressSpace *vtd_as, PCIBus *bus,
     if (s->scalable_modern && s->root_scalable) {
         ret_fr = vtd_iova_to_flpte(s, &ce, addr, is_write, &pte, &level,
                                    &reads, &writes, s->aw_bits, pasid);
+        pgtt = VTD_SM_PASID_ENTRY_FLT;
     } else {
         ret_fr = vtd_iova_to_slpte(s, &ce, addr, is_write, &pte, &level,
                                    &reads, &writes, s->aw_bits, pasid);
+        pgtt = VTD_SM_PASID_ENTRY_SLT;
     }
     if (ret_fr) {
         vtd_report_fault(s, -ret_fr, is_fpd_set, source_id,
@@ -2190,7 +2205,7 @@ static bool vtd_do_iommu_translate(VTDAddressSpace *vtd_as, PCIBus *bus,
     page_mask = vtd_pt_level_page_mask(level);
     access_flags = IOMMU_ACCESS_FLAG(reads, writes);
     vtd_update_iotlb(s, source_id, vtd_get_domain_id(s, &ce, pasid),
-                     addr, pte, access_flags, level, pasid);
+                     addr, pte, access_flags, level, pasid, pgtt);
 out:
     vtd_iommu_unlock(s);
     entry->iova = addr & page_mask;
-- 
2.34.1


Re: [PATCH v3 09/17] intel_iommu: Flush stage-1 cache in iotlb invalidation
Posted by Jason Wang 1 month, 2 weeks ago
On Wed, Sep 11, 2024 at 1:26 PM Zhenzhong Duan <zhenzhong.duan@intel.com> wrote:
>
> According to spec, Page-Selective-within-Domain Invalidation (11b):
>
> 1. IOTLB entries caching second-stage mappings (PGTT=010b) or pass-through
> (PGTT=100b) mappings associated with the specified domain-id and the
> input-address range are invalidated.
> 2. IOTLB entries caching first-stage (PGTT=001b) or nested (PGTT=011b)
> mapping associated with specified domain-id are invalidated.
>
> So per spec definition the Page-Selective-within-Domain Invalidation
> needs to flush first stage and nested cached IOTLB enties as well.
>
> We don't support nested yet and pass-through mapping is never cached,
> so what in iotlb cache are only first-stage and second-stage mappings.
>
> Add a tag pgtt in VTDIOTLBEntry to mark PGTT type of the mapping and
> invalidate entries based on PGTT type.
>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> Reviewed-by: Clément Mathieu--Drif<clement.mathieu--drif@eviden.com>
> ---

Acked-by: Jason Wang <jasowang@redhat.com>

Thanks