IOMMU/x86: switch to alternatives-call patching in further instances

This is, once again, to limit the number of indirect calls as much as
possible. The only hook invocation which isn't sensible to convert is
setup(). And of course Arm-only use sites are left alone as well.

Note regarding the introduction / use of local variables in pci.c:
struct pci_dev's involved fields are const. This const propagates, via
typeof(), to the local helper variables in the altcall macros. These
helper variables are, however, used as outputs (and hence can't be
const). In iommu_get_device_group() make use of the new local variables
to also simplify some adjacent code.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Rahul Singh <rahul.singh@arm.com>
Tested-by: Rahul Singh <rahul.singh@arm.com>

diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index 6334370109fc66e33db51314f9ce9ec8005d5bcc..fc18f63bd4ac7af8fe1ddf850fbdc1c6b4233c52 100644 (file)
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -198,7 +198,7 @@ int iommu_domain_init(struct domain *d, unsigned int opts)
         return ret;
 
     hd->platform_ops = iommu_get_ops();
-    ret = hd->platform_ops->init(d);
+    ret = iommu_call(hd->platform_ops, init, d);
     if ( ret || is_system_domain(d) )
         return ret;
 
@@ -233,7 +233,7 @@ void __hwdom_init iommu_hwdom_init(struct domain *d)
 
     register_keyhandler('o', &iommu_dump_page_tables, "dump iommu page tables", 0);
 
-    hd->platform_ops->hwdom_init(d);
+    iommu_vcall(hd->platform_ops, hwdom_init, d);
 }
 
 static void iommu_teardown(struct domain *d)
@@ -576,7 +576,7 @@ int iommu_get_reserved_device_memory(iommu_grdm_t *func, void *ctxt)
     if ( !ops->get_reserved_device_memory )
         return 0;
 
-    return ops->get_reserved_device_memory(func, ctxt);
+    return iommu_call(ops, get_reserved_device_memory, func, ctxt);
 }
 
 bool_t iommu_has_feature(struct domain *d, enum iommu_feature feature)
@@ -603,7 +603,7 @@ static void iommu_dump_page_tables(unsigned char key)
             continue;
         }
 
-        dom_iommu(d)->platform_ops->dump_page_tables(d);
+        iommu_vcall(dom_iommu(d)->platform_ops, dump_page_tables, d);
     }
 
     rcu_read_unlock(&domlist_read_lock);

diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index 0d8ab2e716b8592e38069c64fdd877fd998f050e..1fad80362f0ef3cd80f1fe97f5a7c8a2db28c546 100644 (file)
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -861,15 +861,15 @@ static int deassign_device(struct domain *d, uint16_t seg, uint8_t bus,
         devfn += pdev->phantom_stride;
         if ( PCI_SLOT(devfn) != PCI_SLOT(pdev->devfn) )
             break;
-        ret = hd->platform_ops->reassign_device(d, target, devfn,
-                                                pci_to_dev(pdev));
+        ret = iommu_call(hd->platform_ops, reassign_device, d, target, devfn,
+                         pci_to_dev(pdev));
         if ( ret )
             goto out;
     }
 
     devfn = pdev->devfn;
-    ret = hd->platform_ops->reassign_device(d, target, devfn,
-                                            pci_to_dev(pdev));
+    ret = iommu_call(hd->platform_ops, reassign_device, d, target, devfn,
+                     pci_to_dev(pdev));
     if ( ret )
         goto out;
 
@@ -1300,7 +1300,7 @@ static int iommu_add_device(struct pci_dev *pdev)
 {
     const struct domain_iommu *hd;
     int rc;
-    u8 devfn;
+    unsigned int devfn = pdev->devfn;
 
     if ( !pdev->domain )
         return -EINVAL;
@@ -1311,16 +1311,16 @@ static int iommu_add_device(struct pci_dev *pdev)
     if ( !is_iommu_enabled(pdev->domain) )
         return 0;
 
-    rc = hd->platform_ops->add_device(pdev->devfn, pci_to_dev(pdev));
+    rc = iommu_call(hd->platform_ops, add_device, devfn, pci_to_dev(pdev));
     if ( rc || !pdev->phantom_stride )
         return rc;
 
-    for ( devfn = pdev->devfn ; ; )
+    for ( ; ; )
     {
         devfn += pdev->phantom_stride;
         if ( PCI_SLOT(devfn) != PCI_SLOT(pdev->devfn) )
             return 0;
-        rc = hd->platform_ops->add_device(devfn, pci_to_dev(pdev));
+        rc = iommu_call(hd->platform_ops, add_device, devfn, pci_to_dev(pdev));
         if ( rc )
             printk(XENLOG_WARNING "IOMMU: add %pp failed (%d)\n",
                    &pdev->sbdf, rc);
@@ -1341,7 +1341,7 @@ static int iommu_enable_device(struct pci_dev *pdev)
          !hd->platform_ops->enable_device )
         return 0;
 
-    return hd->platform_ops->enable_device(pci_to_dev(pdev));
+    return iommu_call(hd->platform_ops, enable_device, pci_to_dev(pdev));
 }
 
 static int iommu_remove_device(struct pci_dev *pdev)
@@ -1363,7 +1363,8 @@ static int iommu_remove_device(struct pci_dev *pdev)
         devfn += pdev->phantom_stride;
         if ( PCI_SLOT(devfn) != PCI_SLOT(pdev->devfn) )
             break;
-        rc = hd->platform_ops->remove_device(devfn, pci_to_dev(pdev));
+        rc = iommu_call(hd->platform_ops, remove_device, devfn,
+                        pci_to_dev(pdev));
         if ( !rc )
             continue;
 
@@ -1371,7 +1372,9 @@ static int iommu_remove_device(struct pci_dev *pdev)
         return rc;
     }
 
-    return hd->platform_ops->remove_device(pdev->devfn, pci_to_dev(pdev));
+    devfn = pdev->devfn;
+
+    return iommu_call(hd->platform_ops, remove_device, devfn, pci_to_dev(pdev));
 }
 
 static int device_assigned(u16 seg, u8 bus, u8 devfn)
@@ -1421,7 +1424,8 @@ static int assign_device(struct domain *d, u16 seg, u8 bus, u8 devfn, u32 flag)
 
     pdev->fault.count = 0;
 
-    if ( (rc = hd->platform_ops->assign_device(d, devfn, pci_to_dev(pdev), flag)) )
+    if ( (rc = iommu_call(hd->platform_ops, assign_device, d, devfn,
+                          pci_to_dev(pdev), flag)) )
         goto done;
 
     for ( ; pdev->phantom_stride; rc = 0 )
@@ -1429,7 +1433,8 @@ static int assign_device(struct domain *d, u16 seg, u8 bus, u8 devfn, u32 flag)
         devfn += pdev->phantom_stride;
         if ( PCI_SLOT(devfn) != PCI_SLOT(pdev->devfn) )
             break;
-        rc = hd->platform_ops->assign_device(d, devfn, pci_to_dev(pdev), flag);
+        rc = iommu_call(hd->platform_ops, assign_device, d, devfn,
+                        pci_to_dev(pdev), flag);
     }
 
  done:
@@ -1457,24 +1462,24 @@ static int iommu_get_device_group(
     if ( !is_iommu_enabled(d) || !ops->get_device_group_id )
         return 0;
 
-    group_id = ops->get_device_group_id(seg, bus, devfn);
+    group_id = iommu_call(ops, get_device_group_id, seg, bus, devfn);
 
     pcidevs_lock();
     for_each_pdev( d, pdev )
     {
-        if ( (pdev->seg != seg) ||
-             ((pdev->bus == bus) && (pdev->devfn == devfn)) )
+        unsigned int b = pdev->bus;
+        unsigned int df = pdev->devfn;
+
+        if ( (pdev->seg != seg) || ((b == bus) && (df == devfn)) )
             continue;
 
-        if ( xsm_get_device_group(XSM_HOOK, (seg << 16) | (pdev->bus << 8) | pdev->devfn) )
+        if ( xsm_get_device_group(XSM_HOOK, (seg << 16) | (b << 8) | df) )
             continue;
 
-        sdev_id = ops->get_device_group_id(seg, pdev->bus, pdev->devfn);
+        sdev_id = iommu_call(ops, get_device_group_id, seg, b, df);
         if ( (sdev_id == group_id) && (i < max_sdevs) )
         {
-            bdf = 0;
-            bdf |= (pdev->bus & 0xff) << 16;
-            bdf |= (pdev->devfn & 0xff) << 8;
+            bdf = (b << 16) | (df << 8);
 
             if ( unlikely(copy_to_guest_offset(buf, i, &bdf, 1)) )
             {

diff --git a/xen/drivers/passthrough/x86/iommu.c b/xen/drivers/passthrough/x86/iommu.c
index f11280f4b208597a1eaab1dbe78f5f857cc6d4a3..583abed9bd1513d0b521782065edff9ab8eda153 100644 (file)
--- a/xen/drivers/passthrough/x86/iommu.c
+++ b/xen/drivers/passthrough/x86/iommu.c
@@ -145,7 +145,7 @@ unsigned int iommu_read_apic_from_ire(unsigned int apic, unsigned int reg)
 int __init iommu_setup_hpet_msi(struct msi_desc *msi)
 {
     const struct iommu_ops *ops = iommu_get_ops();
-    return ops->setup_hpet_msi ? ops->setup_hpet_msi(msi) : -ENODEV;
+    return ops->setup_hpet_msi ? iommu_call(ops, setup_hpet_msi, msi) : -ENODEV;
 }
 
 void __hwdom_init arch_iommu_check_autotranslated_hwdom(struct domain *d)
@@ -406,7 +406,7 @@ int iommu_free_pgtables(struct domain *d)
      * Pages will be moved to the free list below. So we want to
      * clear the root page-table to avoid any potential use after-free.
      */
-    hd->platform_ops->clear_root_pgtable(d);
+    iommu_vcall(hd->platform_ops, clear_root_pgtable, d);
 
     while ( (pg = page_list_remove_head(&hd->arch.pgtables.list)) )
     {