Fix lock issue for hvm pass-through domain

This patch protect the hvm_irq_dpci structure with evtchn_lock, thus
the access to domain's pirq_vector mapping is also protected.

Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com>

9 files changed, 137 insertions, 87 deletions

diff --git a/xen/arch/x86/hvm/svm/intr.c b/xen/arch/x86/hvm/svm/intr.c
index 7fec5dc35e..9027790247 100644
--- a/xen/arch/x86/hvm/svm/intr.c
+++ b/xen/arch/x86/hvm/svm/intr.c
@@ -124,9 +124,11 @@ static void svm_dirq_assist(struct vcpu *v)
         if ( !test_and_clear_bit(irq, &hvm_irq_dpci->dirq_mask) )
             continue;
 
+        spin_lock(&d->evtchn_lock);
         if ( test_bit(_HVM_IRQ_DPCI_MSI, &hvm_irq_dpci->mirq[irq].flags) )
         {
             hvm_pci_msi_assert(d, irq);
+            spin_unlock(&d->evtchn_lock);
             continue;
         }
 
@@ -137,9 +139,7 @@ static void svm_dirq_assist(struct vcpu *v)
             device = digl->device;
             intx = digl->intx;
             hvm_pci_intx_assert(d, device, intx);
-            spin_lock(&hvm_irq_dpci->dirq_lock);
             hvm_irq_dpci->mirq[irq].pending++;
-            spin_unlock(&hvm_irq_dpci->dirq_lock);
         }
 
         /*
@@ -151,6 +151,7 @@ static void svm_dirq_assist(struct vcpu *v)
          */
         set_timer(&hvm_irq_dpci->hvm_timer[domain_irq_to_vector(d, irq)],
                   NOW() + PT_IRQ_TIME_OUT);
+        spin_unlock(&d->evtchn_lock);
     }
 }
 
diff --git a/xen/arch/x86/hvm/vmsi.c b/xen/arch/x86/hvm/vmsi.c
index d6ad008f4a..6eefb61bfa 100644
--- a/xen/arch/x86/hvm/vmsi.c
+++ b/xen/arch/x86/hvm/vmsi.c
@@ -134,7 +134,7 @@ int vmsi_deliver(struct domain *d, int pirq)
                 "vector=%x trig_mode=%x\n",
                 dest, dest_mode, delivery_mode, vector, trig_mode);
 
-    if ( !(hvm_irq_dpci->mirq[pirq].flags & HVM_IRQ_DPCI_MSI) )
+    if ( !test_bit(_HVM_IRQ_DPCI_MSI, &hvm_irq_dpci->mirq[pirq].flags) )
     {
         gdprintk(XENLOG_WARNING, "pirq %x not msi \n", pirq);
         return 0;
diff --git a/xen/arch/x86/hvm/vmx/intr.c b/xen/arch/x86/hvm/vmx/intr.c
index 7379066734..808446f4c9 100644
--- a/xen/arch/x86/hvm/vmx/intr.c
+++ b/xen/arch/x86/hvm/vmx/intr.c
@@ -127,11 +127,13 @@ static void vmx_dirq_assist(struct vcpu *v)
         if ( !test_and_clear_bit(irq, &hvm_irq_dpci->dirq_mask) )
             continue;
 
-		if ( test_bit(_HVM_IRQ_DPCI_MSI, &hvm_irq_dpci->mirq[irq].flags) )
-		{
-			hvm_pci_msi_assert(d, irq);
-			continue;
-		}
+        spin_lock(&d->evtchn_lock);
+        if ( test_bit(_HVM_IRQ_DPCI_MSI, &hvm_irq_dpci->mirq[irq].flags) )
+        {
+            hvm_pci_msi_assert(d, irq);
+            spin_unlock(&d->evtchn_lock);
+            continue;
+        }
 
         stop_timer(&hvm_irq_dpci->hvm_timer[domain_irq_to_vector(d, irq)]);
 
@@ -140,9 +142,7 @@ static void vmx_dirq_assist(struct vcpu *v)
             device = digl->device;
             intx = digl->intx;
             hvm_pci_intx_assert(d, device, intx);
-            spin_lock(&hvm_irq_dpci->dirq_lock);
             hvm_irq_dpci->mirq[irq].pending++;
-            spin_unlock(&hvm_irq_dpci->dirq_lock);
         }
 
         /*
@@ -154,6 +154,7 @@ static void vmx_dirq_assist(struct vcpu *v)
          */
         set_timer(&hvm_irq_dpci->hvm_timer[domain_irq_to_vector(d, irq)],
                   NOW() + PT_IRQ_TIME_OUT);
+        spin_unlock(&d->evtchn_lock);
     }
 }
 
diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
index 718b3dde39..eb1d2ef776 100644
--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -285,7 +285,7 @@ static void __do_IRQ_guest(int vector)
  * The descriptor is returned locked. This function is safe against changes
  * to the per-domain irq-to-vector mapping.
  */
-static irq_desc_t *domain_spin_lock_irq_desc(
+irq_desc_t *domain_spin_lock_irq_desc(
     struct domain *d, int irq, unsigned long *pflags)
 {
     unsigned int vector;
diff --git a/xen/drivers/passthrough/io.c b/xen/drivers/passthrough/io.c
index c8d81bcefa..074fc35183 100644
--- a/xen/drivers/passthrough/io.c
+++ b/xen/drivers/passthrough/io.c
@@ -26,10 +26,14 @@ static void pt_irq_time_out(void *data)
     struct hvm_mirq_dpci_mapping *irq_map = data;
     unsigned int guest_gsi, machine_gsi = 0;
     int vector;
-    struct hvm_irq_dpci *dpci = domain_get_irq_dpci(irq_map->dom);
+    struct hvm_irq_dpci *dpci = NULL;
     struct dev_intx_gsi_link *digl;
     uint32_t device, intx;
 
+    spin_lock(&irq_map->dom->evtchn_lock);
+
+    dpci = domain_get_irq_dpci(irq_map->dom);
+    ASSERT(dpci);
     list_for_each_entry ( digl, &irq_map->digl_list, list )
     {
         guest_gsi = digl->gsi;
@@ -41,55 +45,65 @@ static void pt_irq_time_out(void *data)
 
     clear_bit(machine_gsi, dpci->dirq_mask);
     vector = domain_irq_to_vector(irq_map->dom, machine_gsi);
-    stop_timer(&dpci->hvm_timer[vector]);
-    spin_lock(&dpci->dirq_lock);
     dpci->mirq[machine_gsi].pending = 0;
-    spin_unlock(&dpci->dirq_lock);
+    spin_unlock(&irq_map->dom->evtchn_lock);
     pirq_guest_eoi(irq_map->dom, machine_gsi);
 }
 
 int pt_irq_create_bind_vtd(
     struct domain *d, xen_domctl_bind_pt_irq_t *pt_irq_bind)
 {
-    struct hvm_irq_dpci *hvm_irq_dpci = domain_get_irq_dpci(d);
+    struct hvm_irq_dpci *hvm_irq_dpci = NULL;
     uint32_t machine_gsi, guest_gsi;
     uint32_t device, intx, link;
     struct dev_intx_gsi_link *digl;
+    int pirq = pt_irq_bind->machine_irq;
+
+    if ( pirq < 0 || pirq >= NR_PIRQS )
+        return -EINVAL;
+
+    spin_lock(&d->evtchn_lock);
 
+    hvm_irq_dpci = domain_get_irq_dpci(d);
     if ( hvm_irq_dpci == NULL )
     {
         hvm_irq_dpci = xmalloc(struct hvm_irq_dpci);
         if ( hvm_irq_dpci == NULL )
+        {
+            spin_unlock(&d->evtchn_lock);
             return -ENOMEM;
-
+        }
         memset(hvm_irq_dpci, 0, sizeof(*hvm_irq_dpci));
-        spin_lock_init(&hvm_irq_dpci->dirq_lock);
         for ( int i = 0; i < NR_IRQS; i++ )
             INIT_LIST_HEAD(&hvm_irq_dpci->mirq[i].digl_list);
+    }
 
-        if ( domain_set_irq_dpci(d, hvm_irq_dpci) == 0 )
-            xfree(hvm_irq_dpci);
+    if ( domain_set_irq_dpci(d, hvm_irq_dpci) == 0 )
+    {
+        xfree(hvm_irq_dpci);
+        spin_unlock(&d->evtchn_lock);
+        return -EINVAL;
     }
 
     if ( pt_irq_bind->irq_type == PT_IRQ_TYPE_MSI )
     {
-        int pirq = pt_irq_bind->machine_irq;
-
-        if ( pirq < 0 || pirq >= NR_IRQS )
-            return -EINVAL;
 
-        if ( !(hvm_irq_dpci->mirq[pirq].flags & HVM_IRQ_DPCI_VALID ) )
+        if ( !test_and_set_bit(pirq, hvm_irq_dpci->mapping))
         {
-            hvm_irq_dpci->mirq[pirq].flags |= HVM_IRQ_DPCI_VALID |
-                                              HVM_IRQ_DPCI_MSI ;
+            set_bit(_HVM_IRQ_DPCI_MSI, &hvm_irq_dpci->mirq[pirq].flags);
+            hvm_irq_dpci->mirq[pirq].gmsi.gvec = pt_irq_bind->u.msi.gvec;
+            hvm_irq_dpci->mirq[pirq].gmsi.gflags = pt_irq_bind->u.msi.gflags;
+            hvm_irq_dpci->msi_gvec_pirq[pt_irq_bind->u.msi.gvec] = pirq;
+            /* bind after hvm_irq_dpci is setup to avoid race with irq handler*/
             pirq_guest_bind(d->vcpu[0], pirq, 0);
         }
+        else if (hvm_irq_dpci->mirq[pirq].gmsi.gvec != pt_irq_bind->u.msi.gvec
+                ||hvm_irq_dpci->msi_gvec_pirq[pt_irq_bind->u.msi.gvec] != pirq)
 
-        hvm_irq_dpci->mirq[pirq].flags |= HVM_IRQ_DPCI_VALID |HVM_IRQ_DPCI_MSI ;
-        hvm_irq_dpci->mirq[pirq].gmsi.gvec = pt_irq_bind->u.msi.gvec;
-        hvm_irq_dpci->mirq[pirq].gmsi.gflags = pt_irq_bind->u.msi.gflags;
-        hvm_irq_dpci->msi_gvec_pirq[pt_irq_bind->u.msi.gvec] = pirq;
-
+        {
+            spin_unlock(&d->evtchn_lock);
+            return -EBUSY;
+        }
     }
     else
     {
@@ -102,7 +116,10 @@ int pt_irq_create_bind_vtd(
 
         digl = xmalloc(struct dev_intx_gsi_link);
         if ( !digl )
+        {
+            spin_unlock(&d->evtchn_lock);
             return -ENOMEM;
+        }
 
         digl->device = device;
         digl->intx = intx;
@@ -117,11 +134,11 @@ int pt_irq_create_bind_vtd(
         hvm_irq_dpci->girq[guest_gsi].machine_gsi = machine_gsi;
 
         /* Bind the same mirq once in the same domain */
-        if ( !(hvm_irq_dpci->mirq[machine_gsi].flags & HVM_IRQ_DPCI_VALID) )
+        if ( !test_and_set_bit(machine_gsi, hvm_irq_dpci->mapping))
         {
-            hvm_irq_dpci->mirq[machine_gsi].flags |= HVM_IRQ_DPCI_VALID;
             hvm_irq_dpci->mirq[machine_gsi].dom = d;
 
+            /* Init timer before binding */
             init_timer(&hvm_irq_dpci->hvm_timer[domain_irq_to_vector(d, machine_gsi)],
                        pt_irq_time_out, &hvm_irq_dpci->mirq[machine_gsi], 0);
             /* Deal with gsi for legacy devices */
@@ -132,37 +149,45 @@ int pt_irq_create_bind_vtd(
                  "VT-d irq bind: m_irq = %x device = %x intx = %x\n",
                  machine_gsi, device, intx);
     }
+    spin_unlock(&d->evtchn_lock);
     return 0;
 }
 
 int pt_irq_destroy_bind_vtd(
     struct domain *d, xen_domctl_bind_pt_irq_t *pt_irq_bind)
 {
-    struct hvm_irq_dpci *hvm_irq_dpci = domain_get_irq_dpci(d);
+    struct hvm_irq_dpci *hvm_irq_dpci = NULL;
     uint32_t machine_gsi, guest_gsi;
     uint32_t device, intx, link;
     struct list_head *digl_list, *tmp;
     struct dev_intx_gsi_link *digl;
 
-    if ( hvm_irq_dpci == NULL )
-        return 0;
-
     machine_gsi = pt_irq_bind->machine_irq;
     device = pt_irq_bind->u.pci.device;
     intx = pt_irq_bind->u.pci.intx;
     guest_gsi = hvm_pci_intx_gsi(device, intx);
     link = hvm_pci_intx_link(device, intx);
-    hvm_irq_dpci->link_cnt[link]--;
 
     gdprintk(XENLOG_INFO,
              "pt_irq_destroy_bind_vtd: machine_gsi=%d "
              "guest_gsi=%d, device=%d, intx=%d.\n",
              machine_gsi, guest_gsi, device, intx);
+    spin_lock(&d->evtchn_lock);
+
+    hvm_irq_dpci = domain_get_irq_dpci(d);
+
+    if ( hvm_irq_dpci == NULL )
+    {
+        spin_unlock(&d->evtchn_lock);
+        return -EINVAL;
+    }
+
+    hvm_irq_dpci->link_cnt[link]--;
     memset(&hvm_irq_dpci->girq[guest_gsi], 0,
            sizeof(struct hvm_girq_dpci_mapping));
 
     /* clear the mirq info */
-    if ( (hvm_irq_dpci->mirq[machine_gsi].flags & HVM_IRQ_DPCI_VALID) )
+    if ( test_bit(machine_gsi, hvm_irq_dpci->mapping))
     {
         list_for_each_safe ( digl_list, tmp,
                 &hvm_irq_dpci->mirq[machine_gsi].digl_list )
@@ -185,9 +210,10 @@ int pt_irq_destroy_bind_vtd(
             kill_timer(&hvm_irq_dpci->hvm_timer[domain_irq_to_vector(d, machine_gsi)]);
             hvm_irq_dpci->mirq[machine_gsi].dom   = NULL;
             hvm_irq_dpci->mirq[machine_gsi].flags = 0;
+            clear_bit(machine_gsi, hvm_irq_dpci->mapping);
         }
     }
-
+    spin_unlock(&d->evtchn_lock);
     gdprintk(XENLOG_INFO,
              "XEN_DOMCTL_irq_unmapping: m_irq = %x device = %x intx = %x\n",
              machine_gsi, device, intx);
@@ -199,8 +225,9 @@ int hvm_do_IRQ_dpci(struct domain *d, unsigned int mirq)
 {
     struct hvm_irq_dpci *dpci = domain_get_irq_dpci(d);
 
+    ASSERT(spin_is_locked(&irq_desc[domain_irq_to_vector(d, mirq)].lock));
     if ( !iommu_enabled || (d == dom0) || !dpci ||
-         !dpci->mirq[mirq].flags & HVM_IRQ_DPCI_VALID )
+         !test_bit(mirq, dpci->mapping))
         return 0;
 
     /*
@@ -218,44 +245,46 @@ int hvm_do_IRQ_dpci(struct domain *d, unsigned int mirq)
     return 1;
 }
 
-
 void hvm_dpci_msi_eoi(struct domain *d, int vector)
 {
     struct hvm_irq_dpci *hvm_irq_dpci = d->arch.hvm_domain.irq.dpci;
-    int pirq;
-    unsigned long flags;
     irq_desc_t *desc;
+    int pirq;
 
     if ( !iommu_enabled || (hvm_irq_dpci == NULL) )
        return;
 
+    spin_lock(&d->evtchn_lock);
     pirq = hvm_irq_dpci->msi_gvec_pirq[vector];
 
     if ( ( pirq >= 0 ) && (pirq < NR_PIRQS) &&
-         (hvm_irq_dpci->mirq[pirq].flags & HVM_IRQ_DPCI_VALID) &&
-         (hvm_irq_dpci->mirq[pirq].flags & HVM_IRQ_DPCI_MSI) )
-    {
-        int vec;
-        vec = domain_irq_to_vector(d, pirq);
-        desc = &irq_desc[vec];
-
-        spin_lock_irqsave(&desc->lock, flags);
-        desc->status &= ~IRQ_INPROGRESS;
-        spin_unlock_irqrestore(&desc->lock, flags);
-
-        pirq_guest_eoi(d, pirq);
-    }
+          test_bit(pirq, hvm_irq_dpci->mapping) &&
+         (test_bit(_HVM_IRQ_DPCI_MSI, &hvm_irq_dpci->mirq[pirq].flags)))
+     {
+         BUG_ON(!local_irq_is_enabled());
+         desc = domain_spin_lock_irq_desc(d, pirq, NULL);
+         if (!desc)
+         {
+            spin_unlock(&d->evtchn_lock);
+            return;
+         }
+
+         desc->status &= ~IRQ_INPROGRESS;
+         spin_unlock_irq(&desc->lock);
+
+         pirq_guest_eoi(d, pirq);
+     }
+
+    spin_unlock(&d->evtchn_lock);
 }
 
 void hvm_dpci_eoi(struct domain *d, unsigned int guest_gsi,
                   union vioapic_redir_entry *ent)
 {
-    struct hvm_irq_dpci *hvm_irq_dpci = domain_get_irq_dpci(d);
+    struct hvm_irq_dpci *hvm_irq_dpci = NULL;
     uint32_t device, intx, machine_gsi;
 
-    if ( !iommu_enabled || (hvm_irq_dpci == NULL) ||
-         (guest_gsi >= NR_ISAIRQS &&
-          !hvm_irq_dpci->girq[guest_gsi].valid) )
+    if ( !iommu_enabled)
         return;
 
     if ( guest_gsi < NR_ISAIRQS )
@@ -264,23 +293,34 @@ void hvm_dpci_eoi(struct domain *d, unsigned int guest_gsi,
         return;
     }
 
-    machine_gsi = hvm_irq_dpci->girq[guest_gsi].machine_gsi;
+    spin_lock(&d->evtchn_lock);
+    hvm_irq_dpci = domain_get_irq_dpci(d);
+
+    if((hvm_irq_dpci == NULL) ||
+         (guest_gsi >= NR_ISAIRQS &&
+          !hvm_irq_dpci->girq[guest_gsi].valid) )
+    {
+        spin_unlock(&d->evtchn_lock);
+        return;
+    }
+
     device = hvm_irq_dpci->girq[guest_gsi].device;
     intx = hvm_irq_dpci->girq[guest_gsi].intx;
     hvm_pci_intx_deassert(d, device, intx);
 
-    spin_lock(&hvm_irq_dpci->dirq_lock);
+    machine_gsi = hvm_irq_dpci->girq[guest_gsi].machine_gsi;
     if ( --hvm_irq_dpci->mirq[machine_gsi].pending == 0 )
     {
-        spin_unlock(&hvm_irq_dpci->dirq_lock);
-
         if ( (ent == NULL) || !ent->fields.mask )
         {
+            /*
+             * No need to get vector lock for timer
+             * since interrupt is still not EOIed
+             */
             stop_timer(&hvm_irq_dpci->hvm_timer[
                 domain_irq_to_vector(d, machine_gsi)]);
             pirq_guest_eoi(d, machine_gsi);
         }
     }
-    else
-        spin_unlock(&hvm_irq_dpci->dirq_lock);
+    spin_unlock(&d->evtchn_lock);
 }
diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index df7161d539..fab74611da 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -154,7 +154,7 @@ int pci_remove_device(u8 bus, u8 devfn)
 
 static void pci_clean_dpci_irqs(struct domain *d)
 {
-    struct hvm_irq_dpci *hvm_irq_dpci = domain_get_irq_dpci(d);
+    struct hvm_irq_dpci *hvm_irq_dpci = NULL;
     uint32_t i;
     struct list_head *digl_list, *tmp;
     struct dev_intx_gsi_link *digl;
@@ -165,13 +165,14 @@ static void pci_clean_dpci_irqs(struct domain *d)
     if ( !is_hvm_domain(d) && !need_iommu(d) )
         return;
 
+    spin_lock(&d->evtchn_lock);
+    hvm_irq_dpci = domain_get_irq_dpci(d);
     if ( hvm_irq_dpci != NULL )
     {
-        for ( i = 0; i < NR_IRQS; i++ )
+        for ( i = find_first_bit(hvm_irq_dpci->mapping, NR_PIRQS);
+              i < NR_PIRQS;
+              i = find_next_bit(hvm_irq_dpci->mapping, NR_PIRQS, i + 1) )
         {
-            if ( !(hvm_irq_dpci->mirq[i].flags & HVM_IRQ_DPCI_VALID) )
-                continue;
-
             pirq_guest_unbind(d, i);
             kill_timer(&hvm_irq_dpci->hvm_timer[irq_to_vector(i)]);
 
@@ -188,6 +189,7 @@ static void pci_clean_dpci_irqs(struct domain *d)
         d->arch.hvm_domain.irq.dpci = NULL;
         xfree(hvm_irq_dpci);
     }
+    spin_unlock(&d->evtchn_lock);
 }
 
 void pci_release_devices(struct domain *d)
diff --git a/xen/drivers/passthrough/vtd/x86/vtd.c b/xen/drivers/passthrough/vtd/x86/vtd.c
index 62e7d0d5be..71ec004f4a 100644
--- a/xen/drivers/passthrough/vtd/x86/vtd.c
+++ b/xen/drivers/passthrough/vtd/x86/vtd.c
@@ -85,37 +85,41 @@ int domain_set_irq_dpci(struct domain *domain, struct hvm_irq_dpci *dpci)
 void hvm_dpci_isairq_eoi(struct domain *d, unsigned int isairq)
 {
     struct hvm_irq *hvm_irq = &d->arch.hvm_domain.irq;
-    struct hvm_irq_dpci *dpci = domain_get_irq_dpci(d);
+    struct hvm_irq_dpci *dpci = NULL;
     struct dev_intx_gsi_link *digl, *tmp;
     int i;
 
     ASSERT(isairq < NR_ISAIRQS);
-    if ( !vtd_enabled || !dpci ||
-         !test_bit(isairq, dpci->isairq_map) )
+    if ( !vtd_enabled)
         return;
 
+    spin_lock(&d->evtchn_lock);
+
+    dpci = domain_get_irq_dpci(d);
+
+    if ( !dpci || !test_bit(isairq, dpci->isairq_map) )
+    {
+        spin_unlock(&d->evtchn_lock);
+        return;
+    }
     /* Multiple mirq may be mapped to one isa irq */
-    for ( i = 0; i < NR_IRQS; i++ )
+    for ( i = find_first_bit(dpci->mapping, NR_PIRQS);
+          i < NR_PIRQS;
+          i = find_next_bit(dpci->mapping, NR_PIRQS, i + 1) )
     {
-        if ( !dpci->mirq[i].flags & HVM_IRQ_DPCI_VALID )
-            continue;
-
         list_for_each_entry_safe ( digl, tmp,
             &dpci->mirq[i].digl_list, list )
         {
             if ( hvm_irq->pci_link.route[digl->link] == isairq )
             {
                 hvm_pci_intx_deassert(d, digl->device, digl->intx);
-                spin_lock(&dpci->dirq_lock);
                 if ( --dpci->mirq[i].pending == 0 )
                 {
-                    spin_unlock(&dpci->dirq_lock);
                     stop_timer(&dpci->hvm_timer[domain_irq_to_vector(d, i)]);
                     pirq_guest_eoi(d, i);
                 }
-                else
-                    spin_unlock(&dpci->dirq_lock);
             }
         }
     }
+    spin_unlock(&d->evtchn_lock);
 }
diff --git a/xen/include/asm-x86/hvm/irq.h b/xen/include/asm-x86/hvm/irq.h
index 1daa60c244..ed0bf0f4fd 100644
--- a/xen/include/asm-x86/hvm/irq.h
+++ b/xen/include/asm-x86/hvm/irq.h
@@ -25,6 +25,7 @@
 #include <xen/types.h>
 #include <xen/spinlock.h>
 #include <asm/irq.h>
+#include <asm/pirq.h>
 #include <asm/hvm/hvm.h>
 #include <asm/hvm/vpic.h>
 #include <asm/hvm/vioapic.h>
@@ -38,8 +39,6 @@ struct dev_intx_gsi_link {
     uint8_t link;
 };
 
-#define HVM_IRQ_DPCI_VALID 0x1
-#define HVM_IRQ_DPCI_MSI   0x2
 #define _HVM_IRQ_DPCI_MSI  0x1
 
 struct hvm_gmsi_info {
@@ -64,9 +63,10 @@ struct hvm_girq_dpci_mapping {
 
 #define NR_ISAIRQS  16
 #define NR_LINK     4
+/* Protected by domain's evtchn_lock */
 struct hvm_irq_dpci {
-    spinlock_t dirq_lock;
     /* Machine IRQ to guest device/intx mapping. */
+    DECLARE_BITMAP(mapping, NR_PIRQS);
     struct hvm_mirq_dpci_mapping mirq[NR_IRQS];
     /* Guest IRQ to guest device/intx mapping. */
     struct hvm_girq_dpci_mapping girq[NR_IRQS];
diff --git a/xen/include/xen/irq.h b/xen/include/xen/irq.h
index 71f17d6e87..a4dd3f6333 100644
--- a/xen/include/xen/irq.h
+++ b/xen/include/xen/irq.h
@@ -78,6 +78,8 @@ extern int pirq_guest_eoi(struct domain *d, int irq);
 extern int pirq_guest_unmask(struct domain *d);
 extern int pirq_guest_bind(struct vcpu *v, int irq, int will_share);
 extern void pirq_guest_unbind(struct domain *d, int irq);
+extern irq_desc_t *domain_spin_lock_irq_desc(
+    struct domain *d, int irq, unsigned long *pflags);
 
 static inline void set_native_irq_info(int irq, cpumask_t mask)
 {