iommu: initialisation cleanup and bugfix.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>

5 files changed, 43 insertions, 95 deletions

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 4418c51ff9..da9c4e2503 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -521,10 +521,10 @@ int arch_domain_create(struct domain *d, unsigned int domcr_flags)
         clear_page(d->shared_info);
         share_xen_page_with_guest(
             virt_to_page(d->shared_info), d, XENSHARE_writable);
-    }
 
-    if ( (rc = iommu_domain_init(d)) != 0 )
-        goto fail;
+        if ( (rc = iommu_domain_init(d)) != 0 )
+            goto fail;
+    }
 
     if ( is_hvm_domain(d) )
     {
@@ -562,7 +562,8 @@ void arch_domain_destroy(struct domain *d)
     if ( is_hvm_domain(d) )
         hvm_domain_destroy(d);
 
-    iommu_domain_destroy(d);
+    if ( !is_idle_domain(d) )
+        iommu_domain_destroy(d);
 
     paging_final_teardown(d);
 
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 3f271890fb..cc54a4ac5f 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1019,8 +1019,6 @@ void __init __start_xen(unsigned long mbi_p)
         _initrd_len   = mod[initrdidx].mod_end - mod[initrdidx].mod_start;
     }
 
-    iommu_setup();
-
     /*
      * We're going to setup domain0 using the module(s) that we stashed safely
      * above our heap. The second module, if present, is an initrd ramdisk.
diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index 9fbd41a584..ba32f9af21 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -140,7 +140,7 @@ void deassign_device(struct domain *d, u8 bus, u8 devfn)
     return hd->platform_ops->reassign_device(d, dom0, bus, devfn);
 }
 
-int iommu_setup(void)
+static int iommu_setup(void)
 {
     int rc = -ENODEV;
 
@@ -163,3 +163,4 @@ int iommu_setup(void)
     printk("I/O virtualisation %sabled\n", iommu_enabled ? "en" : "dis");
     return rc;
 }
+__initcall(iommu_setup);
diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index 9396959dc1..d84126bb9d 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -78,7 +78,7 @@ static struct intel_iommu *alloc_intel_iommu(void)
     struct intel_iommu *intel;
 
     intel = xmalloc(struct intel_iommu);
-    if ( !intel )
+    if ( intel == NULL )
     {
         gdprintk(XENLOG_ERR VTDPREFIX,
                  "Allocate intel_iommu failed.\n");
@@ -88,7 +88,6 @@ static struct intel_iommu *alloc_intel_iommu(void)
 
     spin_lock_init(&intel->qi_ctrl.qinval_lock);
     spin_lock_init(&intel->qi_ctrl.qinval_poll_lock);
-
     spin_lock_init(&intel->ir_ctrl.iremap_lock);
 
     return intel;
@@ -96,68 +95,22 @@ static struct intel_iommu *alloc_intel_iommu(void)
 
 static void free_intel_iommu(struct intel_iommu *intel)
 {
-    if ( intel )
-    {
-        xfree(intel);
-        intel = NULL;
-    }
+    xfree(intel);
 }
 
 struct qi_ctrl *iommu_qi_ctrl(struct iommu *iommu)
 {
-    if ( !iommu )
-        return NULL;
-
-    if ( !iommu->intel )
-    {
-        iommu->intel = alloc_intel_iommu();
-        if ( !iommu->intel )
-        {
-            dprintk(XENLOG_ERR VTDPREFIX,
-                    "iommu_qi_ctrl: Allocate iommu->intel failed.\n");
-            return NULL;
-        }
-    }
-
-    return &(iommu->intel->qi_ctrl);
+    return iommu ? &iommu->intel->qi_ctrl : NULL;
 }
 
 struct ir_ctrl *iommu_ir_ctrl(struct iommu *iommu)
 {
-    if ( !iommu )
-        return NULL;
-
-    if ( !iommu->intel )
-    {
-        iommu->intel = alloc_intel_iommu();
-        if ( !iommu->intel )
-        {
-            dprintk(XENLOG_ERR VTDPREFIX,
-                    "iommu_ir_ctrl: Allocate iommu->intel failed.\n");
-            return NULL;
-        }
-    }
-
-    return &(iommu->intel->ir_ctrl);
+    return iommu ? &iommu->intel->ir_ctrl : NULL;
 }
 
 struct iommu_flush *iommu_get_flush(struct iommu *iommu)
 {
-    if ( !iommu )
-        return NULL;
-
-    if ( !iommu->intel )
-    {
-        iommu->intel = alloc_intel_iommu();
-        if ( !iommu->intel )
-        {
-            dprintk(XENLOG_ERR VTDPREFIX,
-                    "iommu_get_flush: Allocate iommu->intel failed.\n");
-            return NULL;
-        }
-    }
-
-    return &(iommu->intel->flush);
+    return iommu ? &iommu->intel->flush : NULL;
 }
 
 unsigned int clflush_size;
@@ -1039,69 +992,65 @@ int iommu_set_interrupt(struct iommu *iommu)
     return vector;
 }
 
-struct iommu *iommu_alloc(void *hw_data)
+static int iommu_alloc(struct acpi_drhd_unit *drhd)
 {
-    struct acpi_drhd_unit *drhd = (struct acpi_drhd_unit *) hw_data;
     struct iommu *iommu;
 
     if ( nr_iommus > MAX_IOMMUS )
     {
         gdprintk(XENLOG_ERR VTDPREFIX,
                  "IOMMU: nr_iommus %d > MAX_IOMMUS\n", nr_iommus);
-        return NULL;
+        return -ENOMEM;
     }
 
     iommu = xmalloc(struct iommu);
-    if ( !iommu )
-        return NULL;
+    if ( iommu == NULL )
+        return -ENOMEM;
     memset(iommu, 0, sizeof(struct iommu));
 
-    set_fixmap_nocache(FIX_IOMMU_REGS_BASE_0 + nr_iommus, drhd->address);
-    iommu->reg = (void *) fix_to_virt(FIX_IOMMU_REGS_BASE_0 + nr_iommus);
-
-    printk("iommu_alloc: iommu->reg = %p drhd->address = %lx\n",
-           iommu->reg, drhd->address);
-
-    nr_iommus++;
-
-    if ( !iommu->reg )
+    iommu->intel = alloc_intel_iommu();
+    if ( iommu->intel == NULL )
     {
-        printk(KERN_ERR VTDPREFIX "IOMMU: can't mapping the region\n");
-        goto error;
+        xfree(iommu);
+        return -ENOMEM;
     }
 
+    set_fixmap_nocache(FIX_IOMMU_REGS_BASE_0 + nr_iommus, drhd->address);
+    iommu->reg = (void *)fix_to_virt(FIX_IOMMU_REGS_BASE_0 + nr_iommus);
+    nr_iommus++;
+
     iommu->cap = dmar_readq(iommu->reg, DMAR_CAP_REG);
     iommu->ecap = dmar_readq(iommu->reg, DMAR_ECAP_REG);
 
-    printk("iommu_alloc: cap = %"PRIx64"\n",iommu->cap);
-    printk("iommu_alloc: ecap = %"PRIx64"\n", iommu->ecap);
-
     spin_lock_init(&iommu->lock);
     spin_lock_init(&iommu->register_lock);
 
-    iommu->intel = alloc_intel_iommu();
 
     drhd->iommu = iommu;
-    return iommu;
- error:
-    xfree(iommu);
-    return NULL;
+    return 0;
 }
 
-static void free_iommu(struct iommu *iommu)
+static void iommu_free(struct acpi_drhd_unit *drhd)
 {
-    if ( !iommu )
+    struct iommu *iommu = drhd->iommu;
+
+    if ( iommu == NULL )
         return;
+
     if ( iommu->root_maddr != 0 )
     {
         free_pgtable_maddr(iommu->root_maddr);
         iommu->root_maddr = 0;
     }
+
     if ( iommu->reg )
         iounmap(iommu->reg);
+
     free_intel_iommu(iommu->intel);
     free_irq(iommu->vector);
     xfree(iommu);
+
+    drhd->iommu = NULL;
 }
 
 #define guestwidth_to_adjustwidth(gaw) ({       \
@@ -1120,10 +1069,10 @@ static int intel_iommu_domain_init(struct domain *domain)
     unsigned long sagaw;
     struct acpi_drhd_unit *drhd;
 
-    for_each_drhd_unit ( drhd )
-        iommu = drhd->iommu ? : iommu_alloc(drhd);
+    drhd = list_entry(acpi_drhd_units.next, typeof(*drhd), list);
+    iommu = drhd->iommu;
 
-    /* calculate AGAW */
+    /* Calculate AGAW. */
     if ( guest_width > cap_mgaw(iommu->cap) )
         guest_width = cap_mgaw(iommu->cap);
     adjust_width = guestwidth_to_adjustwidth(guest_width);
@@ -1913,9 +1862,12 @@ int intel_vtd_setup(void)
     spin_lock_init(&domid_bitmap_lock);
     INIT_LIST_HEAD(&hd->pdev_list);
 
-    /* setup clflush size */
     clflush_size = get_clflush_size();
 
+    for_each_drhd_unit ( drhd )
+        if ( iommu_alloc(drhd) != 0 )
+            goto error;
+
     /* Allocate IO page directory page for the domain. */
     drhd = list_entry(acpi_drhd_units.next, typeof(*drhd), list);
     iommu = drhd->iommu;
@@ -1929,7 +1881,7 @@ int intel_vtd_setup(void)
     memset(domid_bitmap, 0, domid_bitmap_size / 8);
     set_bit(0, domid_bitmap);
 
-    /* setup 1:1 page table for dom0 */
+    /* Set up 1:1 page table for dom0. */
     for ( i = 0; i < max_page; i++ )
         iommu_map_page(dom0, i, i);
 
@@ -1944,10 +1896,7 @@ int intel_vtd_setup(void)
 
  error:
     for_each_drhd_unit ( drhd )
-    {
-        iommu = drhd->iommu;
-        free_iommu(iommu);
-    }
+        iommu_free(drhd);
     vtd_enabled = 0;
     return -ENOMEM;
 }
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 7ad55190fa..b7311be81e 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -71,7 +71,6 @@ struct iommu {
     struct intel_iommu *intel;
 };
 
-int iommu_setup(void);
 int iommu_domain_init(struct domain *d);
 void iommu_domain_destroy(struct domain *d);
 int device_assigned(u8 bus, u8 devfn);