use is_iommu_enabled() where appropriate...

...rather than testing the global iommu_enabled flag and ops pointer.

Now that there is a per-domain flag indicating whether the domain is
permitted to use the IOMMU (which determines whether the ops pointer will
be set), many tests of the global iommu_enabled flag and ops pointer can
be translated into tests of the per-domain flag. Some of the other tests of
purely the global iommu_enabled flag can also be translated into tests of
the per-domain flag.

NOTE: The comment in iommu_share_p2m_table() is also fixed; need_iommu()
      disappeared some time ago. Also, whilst the style of the 'if' in
      flask_iommu_resource_use_perm() is fixed, I have not translated any
      instances of u32 into uint32_t to keep consistency. IMO such a
      translation would be better done globally for the source module in
      a separate patch.
      The change to the definition of iommu_call() is to keep the PV shim
      build happy. Without this change it will fail to compile with errors
      of the form:

iommu.c:361:32: error: unused variable ‘hd’ [-Werror=unused-variable]
     const struct domain_iommu *hd = dom_iommu(d);
                                     ^~
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: "Roger Pau Monné" <roger.pau@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien.grall@arm.com>

xen/arch/arm/p2m.c

@@ -1531,7 +1531,7 @@ int p2m_init(struct domain *d)
      * shared with the CPU, Xen has to make sure that the PT changes have
      * reached the memory
      */
-    p2m->clean_pte = iommu_enabled &&
+    p2m->clean_pte = is_iommu_enabled(d) &&
         !iommu_has_feature(d, IOMMU_FEAT_COHERENT_WALK);
 
     rc = p2m_alloc_table(d);

xen/arch/x86/dom0_build.c

@@ -356,7 +356,7 @@ unsigned long __init dom0_compute_nr_pages(
         avail -= d->max_vcpus - 1;
 
     /* Reserve memory for iommu_dom0_init() (rough estimate). */
-    if ( iommu_enabled )
+    if ( is_iommu_enabled(d) )
     {
         unsigned int s;
 

xen/arch/x86/domctl.c

@@ -708,7 +708,7 @@ long arch_do_domctl(
             break;
 
         ret = -ESRCH;
-        if ( iommu_enabled )
+        if ( is_iommu_enabled(d) )
         {
             pcidevs_lock();
             ret = pt_irq_create_bind(d, bind);
@@ -737,7 +737,7 @@ long arch_do_domctl(
         if ( ret )
             break;
 
-        if ( iommu_enabled )
+        if ( is_iommu_enabled(d) )
         {
             pcidevs_lock();
             ret = pt_irq_destroy_bind(d, bind);

xen/arch/x86/hvm/hvm.c

@@ -465,7 +465,7 @@ void hvm_migrate_timers(struct vcpu *v)
 
 void hvm_migrate_pirq(struct hvm_pirq_dpci *pirq_dpci, const struct vcpu *v)
 {
-    ASSERT(iommu_enabled &&
+    ASSERT(is_iommu_enabled(v->domain) &&
            (is_hardware_domain(v->domain) || hvm_domain_irq(v->domain)->dpci));
 
     if ( (pirq_dpci->flags & HVM_IRQ_DPCI_MACH_MSI) &&
@@ -496,7 +496,7 @@ void hvm_migrate_pirqs(struct vcpu *v)
 {
     struct domain *d = v->domain;
 
-    if ( !iommu_enabled || !hvm_domain_irq(d)->dpci )
+    if ( !is_iommu_enabled(d) || !hvm_domain_irq(d)->dpci )
        return;
 
     spin_lock(&d->event_lock);
@@ -2264,7 +2264,7 @@ int hvm_set_cr0(unsigned long value, bool may_defer)
     }
 
     if ( ((value ^ old_value) & X86_CR0_CD) &&
-         iommu_enabled && hvm_funcs.handle_cd &&
+         is_iommu_enabled(d) && hvm_funcs.handle_cd &&
          (!rangeset_is_empty(d->iomem_caps) ||
           !rangeset_is_empty(d->arch.ioport_caps) ||
           has_arch_pdevs(d)) )

xen/arch/x86/hvm/vioapic.c

@@ -536,7 +536,7 @@ void vioapic_update_EOI(struct domain *d, u8 vector)
 
             ent->fields.remote_irr = 0;
 
-            if ( iommu_enabled )
+            if ( is_iommu_enabled(d) )
             {
                 spin_unlock(&d->arch.hvm.irq_lock);
                 hvm_dpci_eoi(d, vioapic->base_gsi + pin, ent);

xen/arch/x86/hvm/vmx/vmcs.c

@@ -1087,7 +1087,7 @@ static int construct_vmcs(struct vcpu *v)
         vmx_clear_msr_intercept(v, MSR_IA32_SYSENTER_CS, VMX_MSR_RW);
         vmx_clear_msr_intercept(v, MSR_IA32_SYSENTER_ESP, VMX_MSR_RW);
         vmx_clear_msr_intercept(v, MSR_IA32_SYSENTER_EIP, VMX_MSR_RW);
-        if ( paging_mode_hap(d) && (!iommu_enabled || iommu_snoop) )
+        if ( paging_mode_hap(d) && (!is_iommu_enabled(d) || iommu_snoop) )
             vmx_clear_msr_intercept(v, MSR_IA32_CR_PAT, VMX_MSR_RW);
         if ( (vmexit_ctl & VM_EXIT_CLEAR_BNDCFGS) &&
              (vmentry_ctl & VM_ENTRY_LOAD_BNDCFGS) )

xen/arch/x86/hvm/vmx/vmx.c

@@ -1210,7 +1210,7 @@ static void vmx_handle_cd(struct vcpu *v, unsigned long value)
         {
             v->arch.hvm.cache_mode = NORMAL_CACHE_MODE;
             vmx_set_guest_pat(v, *pat);
-            if ( !iommu_enabled || iommu_snoop )
+            if ( !is_iommu_enabled(v->domain) || iommu_snoop )
                 vmx_clear_msr_intercept(v, MSR_IA32_CR_PAT, VMX_MSR_RW);
             hvm_asid_flush_vcpu(v); /* no need to flush cache */
         }

xen/arch/x86/mm/p2m-ept.c

@@ -260,7 +260,7 @@ static bool_t ept_split_super_page(struct p2m_domain *p2m,
         *epte = *ept_entry;
         epte->sp = (level > 1);
         epte->mfn += i * trunk;
-        epte->snp = (iommu_enabled && iommu_snoop);
+        epte->snp = is_iommu_enabled(p2m->domain) && iommu_snoop;
         epte->suppress_ve = 1;
 
         ept_p2m_type_to_flags(p2m, epte, epte->sa_p2mt, epte->access);
@@ -772,7 +772,7 @@ ept_set_entry(struct p2m_domain *p2m, gfn_t gfn_, mfn_t mfn,
         new_entry.sp = !!i;
         new_entry.sa_p2mt = p2mt;
         new_entry.access = p2ma;
-        new_entry.snp = (iommu_enabled && iommu_snoop);
+        new_entry.snp = is_iommu_enabled(d) && iommu_snoop;
 
         /* the caller should take care of the previous page */
         new_entry.mfn = mfn_x(mfn);

xen/drivers/passthrough/amd/iommu_guest.c

@@ -821,7 +821,7 @@ int guest_iommu_init(struct domain* d)
     struct guest_iommu *iommu;
     struct domain_iommu *hd = dom_iommu(d);
 
-    if ( !is_hvm_domain(d) || !iommu_enabled || !iommuv2_enabled ||
+    if ( !is_hvm_domain(d) || !is_iommu_enabled(d) || !iommuv2_enabled ||
          !has_viommu(d) )
         return 0;
 

xen/drivers/passthrough/device_tree.c

@@ -29,7 +29,7 @@ int iommu_assign_dt_device(struct domain *d, struct dt_device_node *dev)
     int rc = -EBUSY;
     struct domain_iommu *hd = dom_iommu(d);
 
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(d) )
         return -EINVAL;
 
     if ( !dt_device_is_protected(dev) )
@@ -71,7 +71,7 @@ int iommu_deassign_dt_device(struct domain *d, struct dt_device_node *dev)
     const struct domain_iommu *hd = dom_iommu(d);
     int rc;
 
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(d) )
         return -EINVAL;
 
     if ( !dt_device_is_protected(dev) )

xen/drivers/passthrough/io.c

@@ -434,7 +434,7 @@ int pt_irq_create_bind(
             if ( vcpu )
                 pirq_dpci->gmsi.posted = true;
         }
-        if ( vcpu && iommu_enabled )
+        if ( vcpu && is_iommu_enabled(d) )
             hvm_migrate_pirq(pirq_dpci, vcpu);
 
         /* Use interrupt posting if it is supported. */
@@ -817,7 +817,7 @@ int hvm_do_IRQ_dpci(struct domain *d, struct pirq *pirq)
 
     ASSERT(is_hvm_domain(d));
 
-    if ( !iommu_enabled || (!is_hardware_domain(d) && !dpci) ||
+    if ( !is_iommu_enabled(d) || (!is_hardware_domain(d) && !dpci) ||
          !pirq_dpci || !(pirq_dpci->flags & HVM_IRQ_DPCI_MAPPED) )
         return 0;
 
@@ -869,7 +869,7 @@ static int _hvm_dpci_msi_eoi(struct domain *d,
 
 void hvm_dpci_msi_eoi(struct domain *d, int vector)
 {
-    if ( !iommu_enabled ||
+    if ( !is_iommu_enabled(d) ||
          (!hvm_domain_irq(d)->dpci && !is_hardware_domain(d)) )
        return;
 
@@ -1001,7 +1001,7 @@ void hvm_dpci_eoi(struct domain *d, unsigned int guest_gsi,
     const struct hvm_irq_dpci *hvm_irq_dpci;
     const struct hvm_girq_dpci_mapping *girq;
 
-    if ( !iommu_enabled )
+    if ( !is_iommu_enabled(d) )
         return;
 
     if ( is_hardware_domain(d) )

xen/drivers/passthrough/iommu.c

@@ -183,7 +183,7 @@ void __hwdom_init iommu_hwdom_init(struct domain *d)
 
     check_hwdom_reqs(d);
 
-    if ( !iommu_enabled )
+    if ( !is_iommu_enabled(d) )
         return;
 
     register_keyhandler('o', &iommu_dump_p2m_table, "dump iommu p2m table", 0);
@@ -288,7 +288,7 @@ int iommu_construct(struct domain *d)
 
 void iommu_domain_destroy(struct domain *d)
 {
-    if ( !iommu_enabled || !dom_iommu(d)->platform_ops )
+    if ( !is_iommu_enabled(d) )
         return;
 
     iommu_teardown(d);
@@ -304,7 +304,7 @@ int iommu_map(struct domain *d, dfn_t dfn, mfn_t mfn,
     unsigned long i;
     int rc = 0;
 
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(d) )
         return 0;
 
     ASSERT(IS_ALIGNED(dfn_x(dfn), (1ul << page_order)));
@@ -364,7 +364,7 @@ int iommu_unmap(struct domain *d, dfn_t dfn, unsigned int page_order,
     unsigned long i;
     int rc = 0;
 
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(d) )
         return 0;
 
     ASSERT(IS_ALIGNED(dfn_x(dfn), (1ul << page_order)));
@@ -417,7 +417,7 @@ int iommu_lookup_page(struct domain *d, dfn_t dfn, mfn_t *mfn,
 {
     const struct domain_iommu *hd = dom_iommu(d);
 
-    if ( !iommu_enabled || !hd->platform_ops || !hd->platform_ops->lookup_page )
+    if ( !is_iommu_enabled(d) || !hd->platform_ops->lookup_page )
         return -EOPNOTSUPP;
 
     return iommu_call(hd->platform_ops, lookup_page, d, dfn, mfn, flags);
@@ -446,8 +446,8 @@ int iommu_iotlb_flush(struct domain *d, dfn_t dfn, unsigned int page_count,
     const struct domain_iommu *hd = dom_iommu(d);
     int rc;
 
-    if ( !iommu_enabled || !hd->platform_ops ||
-         !hd->platform_ops->iotlb_flush || !page_count || !flush_flags )
+    if ( !is_iommu_enabled(d) || !hd->platform_ops->iotlb_flush ||
+         !page_count || !flush_flags )
         return 0;
 
     if ( dfn_eq(dfn, INVALID_DFN) )
@@ -474,8 +474,8 @@ int iommu_iotlb_flush_all(struct domain *d, unsigned int flush_flags)
     const struct domain_iommu *hd = dom_iommu(d);
     int rc;
 
-    if ( !iommu_enabled || !hd->platform_ops ||
-         !hd->platform_ops->iotlb_flush_all || !flush_flags )
+    if ( !is_iommu_enabled(d) || !hd->platform_ops->iotlb_flush_all ||
+         !flush_flags )
         return 0;
 
     /*
@@ -560,8 +560,8 @@ int iommu_do_domctl(
 {
     int ret = -ENODEV;
 
-    if ( !iommu_enabled )
-        return -ENOSYS;
+    if ( !is_iommu_enabled(d) )
+        return -EOPNOTSUPP;
 
 #ifdef CONFIG_HAS_PCI
     ret = iommu_do_pci_domctl(domctl, d, u_domctl);
@@ -580,9 +580,9 @@ void iommu_share_p2m_table(struct domain* d)
     ASSERT(hap_enabled(d));
     /*
      * iommu_use_hap_pt(d) cannot be used here because during domain
-     * construction need_iommu(d) will always return false here.
+     * construction has_iommu_pt(d) will always return false here.
      */
-    if ( iommu_enabled && iommu_hap_pt_share )
+    if ( is_iommu_enabled(d) && iommu_hap_pt_share )
         iommu_get_ops()->share_p2m(d);
 }
 
@@ -612,10 +612,7 @@ int iommu_get_reserved_device_memory(iommu_grdm_t *func, void *ctxt)
 
 bool_t iommu_has_feature(struct domain *d, enum iommu_feature feature)
 {
-    if ( !iommu_enabled )
-        return 0;
-
-    return test_bit(feature, dom_iommu(d)->features);
+    return is_iommu_enabled(d) && test_bit(feature, dom_iommu(d)->features);
 }
 
 static void iommu_dump_p2m_table(unsigned char key)

xen/drivers/passthrough/pci.c

@@ -601,7 +601,7 @@ static void pci_enable_acs(struct pci_dev *pdev)
     u16 cap, ctrl, seg = pdev->seg;
     u8 bus = pdev->bus;
 
-    if ( !iommu_enabled )
+    if ( !is_iommu_enabled(pdev->domain) )
         return;
 
     pos = pci_find_ext_capability(seg, bus, pdev->devfn, PCI_EXT_CAP_ID_ACS);
@@ -870,7 +870,7 @@ static int pci_clean_dpci_irqs(struct domain *d)
 {
     struct hvm_irq_dpci *hvm_irq_dpci = NULL;
 
-    if ( !iommu_enabled )
+    if ( !is_iommu_enabled(d) )
         return 0;
 
     if ( !is_hvm_domain(d) )
@@ -903,7 +903,7 @@ static int deassign_device(struct domain *d, uint16_t seg, uint8_t bus,
     struct pci_dev *pdev;
     int ret = 0;
 
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(d) )
         return -EINVAL;
 
     ASSERT(pcidevs_locked());
@@ -1389,7 +1389,7 @@ static int iommu_add_device(struct pci_dev *pdev)
     ASSERT(pcidevs_locked());
 
     hd = dom_iommu(pdev->domain);
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(pdev->domain) )
         return 0;
 
     rc = hd->platform_ops->add_device(pdev->devfn, pci_to_dev(pdev));
@@ -1418,7 +1418,7 @@ static int iommu_enable_device(struct pci_dev *pdev)
     ASSERT(pcidevs_locked());
 
     hd = dom_iommu(pdev->domain);
-    if ( !iommu_enabled || !hd->platform_ops ||
+    if ( !is_iommu_enabled(pdev->domain) ||
          !hd->platform_ops->enable_device )
         return 0;
 
@@ -1434,7 +1434,7 @@ static int iommu_remove_device(struct pci_dev *pdev)
         return -EINVAL;
 
     hd = dom_iommu(pdev->domain);
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(pdev->domain) )
         return 0;
 
     for ( devfn = pdev->devfn ; pdev->phantom_stride; )
@@ -1477,7 +1477,7 @@ static int assign_device(struct domain *d, u16 seg, u8 bus, u8 devfn, u32 flag)
     struct pci_dev *pdev;
     int rc = 0;
 
-    if ( !iommu_enabled || !hd->platform_ops )
+    if ( !is_iommu_enabled(d) )
         return 0;
 
     /* Prevent device assign if mem paging or mem sharing have been 
@@ -1543,7 +1543,7 @@ static int iommu_get_device_group(
     int i = 0;
     const struct iommu_ops *ops = hd->platform_ops;
 
-    if ( !iommu_enabled || !ops || !ops->get_device_group_id )
+    if ( !is_iommu_enabled(d) || !ops->get_device_group_id )
         return 0;
 
     group_id = ops->get_device_group_id(seg, bus, devfn);

xen/drivers/passthrough/vtd/iommu.c

@@ -1719,7 +1719,7 @@ static void iommu_domain_teardown(struct domain *d)
         xfree(mrmrr);
     }
 
-    ASSERT(iommu_enabled);
+    ASSERT(is_iommu_enabled(d));
 
     /*
      * We can't use iommu_use_hap_pt here because either IOMMU state

xen/drivers/passthrough/vtd/x86/hvm.c

@@ -51,7 +51,7 @@ void hvm_dpci_isairq_eoi(struct domain *d, unsigned int isairq)
     struct hvm_irq_dpci *dpci = NULL;
 
     ASSERT(isairq < NR_ISAIRQS);
-    if ( !iommu_enabled )
+    if ( !is_iommu_enabled(d) )
         return;
 
     spin_lock(&d->event_lock);

xen/drivers/passthrough/x86/iommu.c

@@ -180,7 +180,7 @@ int arch_iommu_populate_page_table(struct domain *d)
 
 void __hwdom_init arch_iommu_check_autotranslated_hwdom(struct domain *d)
 {
-    if ( !iommu_enabled )
+    if ( !is_iommu_enabled(d) )
         panic("Presently, iommu must be enabled for PVH hardware domain\n");
 }
 

xen/include/asm-x86/iommu.h

@@ -61,8 +61,15 @@ extern struct iommu_ops iommu_ops;
 
 #ifdef NDEBUG
 # include <asm/alternative.h>
-# define iommu_call(ops, fn, args...)  alternative_call(iommu_ops.fn, ## args)
-# define iommu_vcall(ops, fn, args...) alternative_vcall(iommu_ops.fn, ## args)
+# define iommu_call(ops, fn, args...) ({      \
+    (void)(ops);                              \
+    alternative_call(iommu_ops.fn, ## args);  \
+})
+
+# define iommu_vcall(ops, fn, args...) ({     \
+    (void)(ops);                              \
+    alternative_vcall(iommu_ops.fn, ## args); \
+})
 #endif
 
 static inline const struct iommu_ops *iommu_get_ops(void)

xen/xsm/flask/hooks.c

@@ -883,7 +883,7 @@ static int flask_map_domain_msi (struct domain *d, int irq, const void *data,
 #endif
 }
 
-static u32 flask_iommu_resource_use_perm(void)
+static u32 flask_iommu_resource_use_perm(const struct domain *d)
 {
     /* Obtain the permission level required for allowing a domain
      * to use an assigned device.
@@ -896,7 +896,7 @@ static u32 flask_iommu_resource_use_perm(void)
      */
     u32 perm = RESOURCE__USE_NOIOMMU;
 
-    if (iommu_enabled)
+    if ( is_iommu_enabled(d) )
         perm = ( iommu_intremap ? RESOURCE__USE_IOMMU :
                                   RESOURCE__USE_IOMMU_NOINTREMAP );
     return perm;
@@ -907,7 +907,7 @@ static int flask_map_domain_irq (struct domain *d, int irq, const void *data)
     u32 sid, dsid;
     int rc = -EPERM;
     struct avc_audit_data ad;
-    u32 dperm = flask_iommu_resource_use_perm();
+    u32 dperm = flask_iommu_resource_use_perm(d);
 
     if ( irq >= nr_static_irqs && data ) {
         rc = flask_map_domain_msi(d, irq, data, &sid, &ad);
@@ -973,7 +973,7 @@ static int flask_bind_pt_irq (struct domain *d, struct xen_domctl_bind_pt_irq *b
     int rc = -EPERM;
     int irq;
     struct avc_audit_data ad;
-    u32 dperm = flask_iommu_resource_use_perm();
+    u32 dperm = flask_iommu_resource_use_perm(d);
 
     rc = current_has_perm(d, SECCLASS_RESOURCE, RESOURCE__ADD);
     if ( rc )
@@ -1046,7 +1046,7 @@ static int flask_iomem_permission(struct domain *d, uint64_t start, uint64_t end
 
     data.ssid = domain_sid(current->domain);
     data.dsid = domain_sid(d);
-    data.use_perm = flask_iommu_resource_use_perm();
+    data.use_perm = flask_iommu_resource_use_perm(d);
 
     return security_iterate_iomem_sids(start, end, _iomem_has_perm, &data);
 }
@@ -1071,7 +1071,7 @@ static int flask_pci_config_permission(struct domain *d, uint32_t machine_bdf, u
     if ( access && (end >= 0x10 && start < 0x28) )
         perm = RESOURCE__SETUP;
     else
-        perm = flask_iommu_resource_use_perm();
+        perm = flask_iommu_resource_use_perm(d);
 
     AVC_AUDIT_DATA_INIT(&ad, DEV);
     ad.device = (unsigned long) machine_bdf;
@@ -1296,7 +1296,7 @@ static int flask_assign_device(struct domain *d, uint32_t machine_bdf)
     u32 dsid, rsid;
     int rc = -EPERM;
     struct avc_audit_data ad;
-    u32 dperm = flask_iommu_resource_use_perm();
+    u32 dperm = flask_iommu_resource_use_perm(d);
 
     if ( !d )
         return flask_test_assign_device(machine_bdf);
@@ -1355,7 +1355,7 @@ static int flask_assign_dtdevice(struct domain *d, const char *dtpath)
     u32 dsid, rsid;
     int rc = -EPERM;
     struct avc_audit_data ad;
-    u32 dperm = flask_iommu_resource_use_perm();
+    u32 dperm = flask_iommu_resource_use_perm(d);
 
     if ( !d )
         return flask_test_assign_dtdevice(dtpath);
@@ -1540,7 +1540,7 @@ static int flask_ioport_permission(struct domain *d, uint32_t start, uint32_t en
 
     data.ssid = domain_sid(current->domain);
     data.dsid = domain_sid(d);
-    data.use_perm = flask_iommu_resource_use_perm();
+    data.use_perm = flask_iommu_resource_use_perm(d);
 
     return security_iterate_ioport_sids(start, end, _ioport_has_perm, &data);
 }