Merge tag 'iommu-fixes-v3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU fixes from Joerg Roedel:
 "These patches fix a couple of issues.  First of all a few problems
  with ACS on x86 introduced in the last merge window, where ACS did not
  work on AMD and a NULL pointer dereference when there ran against
  SR-IOV devices.

  The patches fallen out of coccinelle checks fix a possible invalid
  memory reference and a possible memory leak.  The other patches mostly
  fix build errors and warnings and a wrong return value."

* tag 'iommu-fixes-v3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Fix ACS path checking
  iommu/intel: Fix ACS path checking
  iommu/amd: Fix pci_request_acs() call-place
  iommu/exynos: Fix build error
  iommu/tegra: smmu: Fix error initial value at domain_init
  iommu/tegra: smmu: Cleanup with lesser nest
  iommu: Add missing forward declaration in include file
  iommu: Include linux/types.h
  iommu/intel: add missing free_domain_mem
  iommu/tegra: remove invalid reference to list iterator variable

6 files changed, 63 insertions, 19 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 6d1cbdfc9b2a..b64502dfa9f4 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -296,8 +296,13 @@ static int iommu_init_device(struct device *dev)
         } else
                 dma_pdev = pci_dev_get(pdev);
 
+        /* Account for quirked devices */
         swap_pci_ref(&dma_pdev, pci_get_dma_source(dma_pdev));
 
+        /*
+         * If it's a multifunction device that does not support our
+         * required ACS flags, add to the same group as function 0.
+         */
         if (dma_pdev->multifunction &&
             !pci_acs_enabled(dma_pdev, REQ_ACS_FLAGS))
                 swap_pci_ref(&dma_pdev,
@@ -305,14 +310,28 @@ static int iommu_init_device(struct device *dev)
                                           PCI_DEVFN(PCI_SLOT(dma_pdev->devfn),
                                           0)));
 
+        /*
+         * Devices on the root bus go through the iommu.  If that's not us,
+         * find the next upstream device and test ACS up to the root bus.
+         * Finding the next device may require skipping virtual buses.
+         */
         while (!pci_is_root_bus(dma_pdev->bus)) {
-                if (pci_acs_path_enabled(dma_pdev->bus->self,
-                                         NULL, REQ_ACS_FLAGS))
+                struct pci_bus *bus = dma_pdev->bus;
+
+                while (!bus->self) {
+                        if (!pci_is_root_bus(bus))
+                                bus = bus->parent;
+                        else
+                                goto root_bus;
+                }
+
+                if (pci_acs_path_enabled(bus->self, NULL, REQ_ACS_FLAGS))
                         break;
 
-                swap_pci_ref(&dma_pdev, pci_dev_get(dma_pdev->bus->self));
+                swap_pci_ref(&dma_pdev, pci_dev_get(bus->self));
         }
 
+root_bus:
         group = iommu_group_get(&dma_pdev->dev);
         pci_dev_put(dma_pdev);
         if (!group) {
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 500e7f15f5c2..0a2ea317120a 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1131,9 +1131,6 @@ static int __init amd_iommu_init_pci(void)
                         break;
         }
 
-        /* Make sure ACS will be enabled */
-        pci_request_acs();
-
         ret = amd_iommu_init_devices();
 
         print_iommu_info();
@@ -1652,6 +1649,9 @@ static bool detect_ivrs(void)
 
         early_acpi_os_unmap_memory((char __iomem *)ivrs_base, ivrs_size);
 
+        /* Make sure ACS will be enabled during PCI probe */
+        pci_request_acs();
+
         return true;
 }
 
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 45350ff5e93c..80bad32aa463 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -732,9 +732,9 @@ static int exynos_iommu_domain_init(struct iommu_domain *domain)
         spin_lock_init(&priv->pgtablelock);
         INIT_LIST_HEAD(&priv->clients);
 
-        dom->geometry.aperture_start = 0;
-        dom->geometry.aperture_end   = ~0UL;
-        dom->geometry.force_aperture = true;
+        domain->geometry.aperture_start = 0;
+        domain->geometry.aperture_end   = ~0UL;
+        domain->geometry.force_aperture = true;
 
         domain->priv = priv;
         return 0;
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 7469b5346643..2297ec193eb4 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -2008,6 +2008,7 @@ static struct dmar_domain *get_domain_for_dev(struct pci_dev *pdev, int gaw)
         if (!drhd) {
                 printk(KERN_ERR "IOMMU: can't find DMAR for device %s\n",
                         pci_name(pdev));
+                free_domain_mem(domain);
                 return NULL;
         }
         iommu = drhd->iommu;
@@ -4124,8 +4125,13 @@ static int intel_iommu_add_device(struct device *dev)
         } else
                 dma_pdev = pci_dev_get(pdev);
 
+        /* Account for quirked devices */
         swap_pci_ref(&dma_pdev, pci_get_dma_source(dma_pdev));
 
+        /*
+         * If it's a multifunction device that does not support our
+         * required ACS flags, add to the same group as function 0.
+         */
         if (dma_pdev->multifunction &&
             !pci_acs_enabled(dma_pdev, REQ_ACS_FLAGS))
                 swap_pci_ref(&dma_pdev,
@@ -4133,14 +4139,28 @@ static int intel_iommu_add_device(struct device *dev)
                                           PCI_DEVFN(PCI_SLOT(dma_pdev->devfn),
                                           0)));
 
+        /*
+         * Devices on the root bus go through the iommu.  If that's not us,
+         * find the next upstream device and test ACS up to the root bus.
+         * Finding the next device may require skipping virtual buses.
+         */
         while (!pci_is_root_bus(dma_pdev->bus)) {
-                if (pci_acs_path_enabled(dma_pdev->bus->self,
-                                         NULL, REQ_ACS_FLAGS))
+                struct pci_bus *bus = dma_pdev->bus;
+
+                while (!bus->self) {
+                        if (!pci_is_root_bus(bus))
+                                bus = bus->parent;
+                        else
+                                goto root_bus;
+                }
+
+                if (pci_acs_path_enabled(bus->self, NULL, REQ_ACS_FLAGS))
                         break;
 
-                swap_pci_ref(&dma_pdev, pci_dev_get(dma_pdev->bus->self));
+                swap_pci_ref(&dma_pdev, pci_dev_get(bus->self));
         }
 
+root_bus:
         group = iommu_group_get(&dma_pdev->dev);
         pci_dev_put(dma_pdev);
         if (!group) {
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 4ba325ab6262..2a4bb36bc688 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -799,14 +799,14 @@ static void smmu_iommu_detach_dev(struct iommu_domain *domain,
                         goto out;
                 }
         }
-        dev_err(smmu->dev, "Couldn't find %s\n", dev_name(c->dev));
+        dev_err(smmu->dev, "Couldn't find %s\n", dev_name(dev));
 out:
         spin_unlock(&as->client_lock);
 }
 
 static int smmu_iommu_domain_init(struct iommu_domain *domain)
 {
-        int i, err = -ENODEV;
+        int i, err = -EAGAIN;
         unsigned long flags;
         struct smmu_as *as;
         struct smmu_device *smmu = smmu_handle;
@@ -814,11 +814,14 @@ static int smmu_iommu_domain_init(struct iommu_domain *domain)
         /* Look for a free AS with lock held */
         for  (i = 0; i < smmu->num_as; i++) {
                 as = &smmu->as[i];
-                if (!as->pdir_page) {
-                        err = alloc_pdir(as);
-                        if (!err)
-                                goto found;
-                }
+
+                if (as->pdir_page)
+                        continue;
+
+                err = alloc_pdir(as);
+                if (!err)
+                        goto found;
+
                 if (err != -EAGAIN)
                         break;
         }
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 54d6d690073c..7e83370e6fd2 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -20,6 +20,7 @@
 #define __LINUX_IOMMU_H
 
 #include <linux/errno.h>
+#include <linux/types.h>
 
 #define IOMMU_READ      (1)
 #define IOMMU_WRITE     (2)
@@ -30,6 +31,7 @@ struct iommu_group;
 struct bus_type;
 struct device;
 struct iommu_domain;
+struct notifier_block;
 
 /* iommu fault flags */
 #define IOMMU_FAULT_READ        0x0