IOMMU: properly check whether interrupt remapping is enabled

... rather than the IOMMU as a whole.

That in turn required to make sure iommu_intremap gets properly
cleared when the respective initialization fails (or isn't being
done at all).

Along with making sure interrupt remapping doesn't get inconsistently
enabled on some IOMMUs and not on others in the VT-d code, this in turn
allowed quite a bit of cleanup on the VT-d side (if desired, that
cleanup could of course be broken out into a separate patch).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: "Zhang, Xiantao" <xiantao.zhang@intel.com>

diff --git a/xen/arch/x86/msi.c b/xen/arch/x86/msi.c
index 88043065d645c2217dd7c453337603079a652088..37ed8f80d26e560576f35750f8e7fee0fdf7810c 100644 (file)
--- a/xen/arch/x86/msi.c
+++ b/xen/arch/x86/msi.c
@@ -210,7 +210,7 @@ static void read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
         BUG();
     }
 
-    if ( iommu_enabled )
+    if ( iommu_intremap )
         iommu_read_msi_from_ire(entry, msg);
 }
 
@@ -218,7 +218,7 @@ static void write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
     entry->msg = *msg;
 
-    if ( iommu_enabled )
+    if ( iommu_intremap )
     {
         ASSERT(msg != &entry->msg);
         iommu_update_ire_from_msi(entry, msg);
@@ -492,7 +492,7 @@ int msi_free_irq(struct msi_desc *entry)
     }
 
     /* Free the unused IRTE if intr remap enabled */
-    if ( iommu_enabled )
+    if ( iommu_intremap )
         iommu_update_ire_from_msi(entry, NULL);
 
     list_del(&entry->list);

diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index c1d3c122e3864a2f7930d6977a86d5123a4a2c35..2db2e174941889df02864ed43b1424c5156d824c 100644 (file)
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -470,6 +470,8 @@ int __init iommu_setup(void)
         rc = iommu_hardware_setup();
         iommu_enabled = (rc == 0);
     }
+    if ( !iommu_enabled )
+        iommu_intremap = 0;
 
     if ( (force_iommu && !iommu_enabled) ||
          (force_intremap && !iommu_intremap) )
@@ -484,9 +486,12 @@ int __init iommu_setup(void)
     }
     printk("I/O virtualisation %sabled\n", iommu_enabled ? "en" : "dis");
     if ( iommu_enabled )
+    {
         printk(" - Dom0 mode: %s\n",
                iommu_passthrough ? "Passthrough" :
                iommu_dom0_strict ? "Strict" : "Relaxed");
+        printk("Interrupt remapping %sabled\n", iommu_intremap ? "en" : "dis");
+    }
 
     return rc;
 }

diff --git a/xen/drivers/passthrough/vtd/intremap.c b/xen/drivers/passthrough/vtd/intremap.c
index a9c3bc4c10acebf1e4977022911bd4786f62977d..0dc1788b24c0d4d47b3b953e6a5f71c38100789c 100644 (file)
--- a/xen/drivers/passthrough/vtd/intremap.c
+++ b/xen/drivers/passthrough/vtd/intremap.c
@@ -373,7 +373,7 @@ unsigned int io_apic_read_remap_rte(
     struct iommu *iommu = ioapic_to_iommu(IO_APIC_ID(apic));
     struct ir_ctrl *ir_ctrl = iommu_ir_ctrl(iommu);
 
-    if ( !ir_ctrl || !ir_ctrl->iremap_maddr || !ir_ctrl->iremap_num ||
+    if ( !ir_ctrl->iremap_num ||
         ( (index = apic_pin_2_ir_idx[apic][ioapic_pin]) < 0 ) )
         return __io_apic_read(apic, reg);
 
@@ -396,15 +396,8 @@ void io_apic_write_remap_rte(
     struct IO_APIC_route_remap_entry *remap_rte;
     unsigned int rte_upper = (reg & 1) ? 1 : 0;
     struct iommu *iommu = ioapic_to_iommu(IO_APIC_ID(apic));
-    struct ir_ctrl *ir_ctrl = iommu_ir_ctrl(iommu);
     int saved_mask;
 
-    if ( !ir_ctrl || !ir_ctrl->iremap_maddr )
-    {
-        __io_apic_write(apic, reg, value);
-        return;
-    }
-
     old_rte = __ioapic_read_entry(apic, ioapic_pin, 1);
 
     remap_rte = (struct IO_APIC_route_remap_entry *) &old_rte;
@@ -653,20 +646,11 @@ void msi_msg_read_remap_rte(
 {
     struct pci_dev *pdev = msi_desc->dev;
     struct acpi_drhd_unit *drhd = NULL;
-    struct iommu *iommu = NULL;
-    struct ir_ctrl *ir_ctrl;
 
     drhd = pdev ? acpi_find_matched_drhd_unit(pdev)
                 : hpet_to_drhd(msi_desc->hpet_id);
-    if ( !drhd )
-        return;
-    iommu = drhd->iommu;
-
-    ir_ctrl = iommu_ir_ctrl(iommu);
-    if ( !ir_ctrl || !ir_ctrl->iremap_maddr )
-        return;
-
-    remap_entry_to_msi_msg(iommu, msg);
+    if ( drhd )
+        remap_entry_to_msi_msg(drhd->iommu, msg);
 }
 
 void msi_msg_write_remap_rte(
@@ -674,20 +658,11 @@ void msi_msg_write_remap_rte(
 {
     struct pci_dev *pdev = msi_desc->dev;
     struct acpi_drhd_unit *drhd = NULL;
-    struct iommu *iommu = NULL;
-    struct ir_ctrl *ir_ctrl;
 
     drhd = pdev ? acpi_find_matched_drhd_unit(pdev)
                 : hpet_to_drhd(msi_desc->hpet_id);
-    if ( !drhd )
-        return;
-    iommu = drhd->iommu;
-
-    ir_ctrl = iommu_ir_ctrl(iommu);
-    if ( !ir_ctrl || !ir_ctrl->iremap_maddr )
-        return;
-
-    msi_msg_to_remap_entry(iommu, pdev, msi_desc, msg);
+    if ( drhd )
+        msi_msg_to_remap_entry(drhd->iommu, pdev, msi_desc, msg);
 }
 
 int __init intel_setup_hpet_msi(struct msi_desc *msi_desc)

diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index 132f04a0836a991987527d7f5c45df63f916d825..ef8bc95b7226c02305164abfc843094803b6e34f 100644 (file)
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -2065,6 +2065,9 @@ static int init_vtd_hw(void)
                 break;
             }
         }
+        if ( !iommu_intremap )
+            for_each_drhd_unit ( drhd )
+                disable_intremap(drhd->iommu);
     }
 
     /*

diff --git a/xen/include/asm-x86/io_apic.h b/xen/include/asm-x86/io_apic.h
index 0cbd04039b24f179e8bd190f772b2ed739c8985e..6d90628055a77221a08670e5520f06a5e74c1aad 100644 (file)
--- a/xen/include/asm-x86/io_apic.h
+++ b/xen/include/asm-x86/io_apic.h
@@ -129,7 +129,7 @@ struct IO_APIC_route_entry {
 extern struct mpc_config_ioapic mp_ioapics[MAX_IO_APICS];
 
 /* Only need to remap ioapic RTE (reg: 10~3Fh) */
-#define ioapic_reg_remapped(reg) (iommu_enabled && ((reg) >= 0x10))
+#define ioapic_reg_remapped(reg) (iommu_intremap && ((reg) >= 0x10))
 
 static inline unsigned int __io_apic_read(unsigned int apic, unsigned int reg)
 {