[xen staging] IOMMU/x86: switch to alternatives-call patching in further instances

[patchbot@xxxxxxx]

commit f66e3d6afcc1315a34475fbee5f46e7110397950
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Mon Jan 31 10:57:27 2022 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Jan 31 10:57:27 2022 +0100

    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@xxxxxxxx>
    Reviewed-by: Paul Durrant <paul@xxxxxxx>
    Reviewed-by: Rahul Singh <rahul.singh@xxxxxxx>
    Tested-by: Rahul Singh <rahul.singh@xxxxxxx>
---
 xen/drivers/passthrough/iommu.c     |  8 +++----
 xen/drivers/passthrough/pci.c       | 47 ++++++++++++++++++++-----------------
 xen/drivers/passthrough/x86/iommu.c |  4 ++--
 3 files changed, 32 insertions(+), 27 deletions(-)

diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index 6334370109..fc18f63bd4 100644
--- 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 0d8ab2e716..1fad80362f 100644
--- 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 f11280f4b2..583abed9bd 100644
--- 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)) )
     {
--
generated by git-patchbot for /home/xen/git/xen.git#staging