From: Jan Beulich <jbeulich@suse.com>
Subject: VT-d: prepare for per-device quarantine page tables (part II)

Replace the passing of struct domain * by domid_t in preparation of
per-device quarantine page tables also requiring per-device pseudo
domain IDs, which aren't going to be associated with any struct domain
instances.

No functional change intended (except for slightly adjusted log message
text).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>

--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -58,8 +58,8 @@ static struct tasklet vtd_fault_tasklet;
 static int setup_hwdom_device(u8 devfn, struct pci_dev *);
 static void setup_hwdom_rmrr(struct domain *d);
 
-static int domain_iommu_domid(struct domain *d,
-                              struct vtd_iommu *iommu)
+static int get_iommu_did(domid_t domid, const struct vtd_iommu *iommu,
+                         bool warn)
 {
     unsigned long nr_dom, i;
 
@@ -67,16 +67,16 @@ static int domain_iommu_domid(struct dom
     i = find_first_bit(iommu->domid_bitmap, nr_dom);
     while ( i < nr_dom )
     {
-        if ( iommu->domid_map[i] == d->domain_id )
+        if ( iommu->domid_map[i] == domid )
             return i;
 
         i = find_next_bit(iommu->domid_bitmap, nr_dom, i+1);
     }
 
-    if ( !d->is_dying )
+    if ( warn )
         dprintk(XENLOG_ERR VTDPREFIX,
-                "Cannot get valid iommu %u domid: %pd\n",
-                iommu->index, d);
+                "No valid iommu %u domid for Dom%d\n",
+                iommu->index, domid);
 
     return -1;
 }
@@ -84,8 +84,7 @@ static int domain_iommu_domid(struct dom
 #define DID_FIELD_WIDTH 16
 #define DID_HIGH_OFFSET 8
 static int context_set_domain_id(struct context_entry *context,
-                                 struct domain *d,
-                                 struct vtd_iommu *iommu)
+                                 domid_t domid, struct vtd_iommu *iommu)
 {
     unsigned long nr_dom, i;
     int found = 0;
@@ -96,7 +95,7 @@ static int context_set_domain_id(struct
     i = find_first_bit(iommu->domid_bitmap, nr_dom);
     while ( i < nr_dom )
     {
-        if ( iommu->domid_map[i] == d->domain_id )
+        if ( iommu->domid_map[i] == domid )
         {
             found = 1;
             break;
@@ -112,7 +111,7 @@ static int context_set_domain_id(struct
             dprintk(XENLOG_ERR VTDPREFIX, "IOMMU: no free domain ids\n");
             return -EFAULT;
         }
-        iommu->domid_map[i] = d->domain_id;
+        iommu->domid_map[i] = domid;
     }
 
     set_bit(i, iommu->domid_bitmap);
@@ -121,9 +120,9 @@ static int context_set_domain_id(struct
     return 0;
 }
 
-static void cleanup_domid_map(struct domain *domain, struct vtd_iommu *iommu)
+static void cleanup_domid_map(domid_t domid, struct vtd_iommu *iommu)
 {
-    int iommu_domid = domain_iommu_domid(domain, iommu);
+    int iommu_domid = get_iommu_did(domid, iommu, false);
 
     if ( iommu_domid >= 0 )
     {
@@ -179,7 +178,7 @@ static void check_cleanup_domid_map(stru
     if ( !found )
     {
         clear_bit(iommu->index, &dom_iommu(d)->arch.iommu_bitmap);
-        cleanup_domid_map(d, iommu);
+        cleanup_domid_map(d->domain_id, iommu);
     }
 }
 
@@ -636,7 +635,7 @@ static int __must_check iommu_flush_iotl
             continue;
 
         flush_dev_iotlb = !!find_ats_dev_drhd(iommu);
-        iommu_domid= domain_iommu_domid(d, iommu);
+        iommu_domid = get_iommu_did(d->domain_id, iommu, !d->is_dying);
         if ( iommu_domid == -1 )
             continue;
 
@@ -1457,7 +1456,7 @@ int domain_context_mapping_one(
         spin_unlock(&hd->arch.mapping_lock);
     }
 
-    rc = context_set_domain_id(&lctxt, domain, iommu);
+    rc = context_set_domain_id(&lctxt, domid, iommu);
     if ( rc )
     {
     unlock:
@@ -1782,7 +1781,7 @@ int domain_context_unmap_one(
     context_clear_entry(*context);
     iommu_sync_cache(context, sizeof(struct context_entry));
 
-    iommu_domid= domain_iommu_domid(domain, iommu);
+    iommu_domid = get_iommu_did(domid, iommu, !domain->is_dying);
     if ( iommu_domid == -1 )
     {
         spin_unlock(&iommu->lock);
@@ -1954,7 +1953,7 @@ static void iommu_domain_teardown(struct
     spin_unlock(&hd->arch.mapping_lock);
 
     for_each_drhd_unit ( drhd )
-        cleanup_domid_map(d, drhd->iommu);
+        cleanup_domid_map(d->domain_id, drhd->iommu);
 }
 
 static int __must_check intel_iommu_map_page(struct domain *d, dfn_t dfn,