Merge branch 'pci/jiang-bus-lock-v3' into next

* pci/jiang-bus-lock-v3:
  PCI: Return early on allocation failures to unindent mainline code
  PCI: Simplify IOV implementation and fix reference count races
  PCI: Drop redundant setting of bus->is_added in virtfn_add_bus()
  unicore32/PCI: Remove redundant call of pci_bus_add_devices()
  m68k/PCI: Remove redundant call of pci_bus_add_devices()
  PCI: Rename pci_release_bus_bridge_dev() to pci_release_host_bridge_dev()
  PCI: Fix refcount issue in pci_create_root_bus() error recovery path
  ia64/PCI: Clean up pci_scan_root_bus() usage
  PCI: Convert alloc_pci_dev(void) to pci_alloc_dev(bus)
  PCI: Introduce pci_alloc_dev(struct pci_bus*) to replace alloc_pci_dev()
  PCI: Introduce pci_bus_{get|put}() to manage PCI bus reference count

Conflicts:
	drivers/pci/probe.c

1 files changed, 25 insertions, 35 deletions

diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index a971a6f6268d..de8ffacf9c9b 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -47,46 +47,36 @@ static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
                 return NULL;
 
         pci_bus_insert_busn_res(child, busnr, busnr);
-        bus->is_added = 1;
 
         return child;
 }
 
-static void virtfn_remove_bus(struct pci_bus *bus, int busnr)
+static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
 {
-        struct pci_bus *child;
-
-        if (bus->number == busnr)
-                return;
-
-        child = pci_find_bus(pci_domain_nr(bus), busnr);
-        BUG_ON(!child);
-
-        if (list_empty(&child->devices))
-                pci_remove_bus(child);
+        if (physbus != virtbus && list_empty(&virtbus->devices))
+                pci_remove_bus(virtbus);
 }
 
 static int virtfn_add(struct pci_dev *dev, int id, int reset)
 {
         int i;
-        int rc;
+        int rc = -ENOMEM;
         u64 size;
         char buf[VIRTFN_ID_LEN];
         struct pci_dev *virtfn;
         struct resource *res;
         struct pci_sriov *iov = dev->sriov;
+        struct pci_bus *bus;
 
-        virtfn = alloc_pci_dev();
+        mutex_lock(&iov->dev->sriov->lock);
+        bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
+        if (!bus)
+                goto failed;
+
+        virtfn = pci_alloc_dev(bus);
         if (!virtfn)
-                return -ENOMEM;
+                goto failed0;
 
-        mutex_lock(&iov->dev->sriov->lock);
-        virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
-        if (!virtfn->bus) {
-                kfree(virtfn);
-                mutex_unlock(&iov->dev->sriov->lock);
-                return -ENOMEM;
-        }
         virtfn->devfn = virtfn_devfn(dev, id);
         virtfn->vendor = dev->vendor;
         pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
@@ -134,7 +124,9 @@ failed1:
         pci_dev_put(dev);
         mutex_lock(&iov->dev->sriov->lock);
         pci_stop_and_remove_bus_device(virtfn);
-        virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
+failed0:
+        virtfn_remove_bus(dev->bus, bus);
+failed:
         mutex_unlock(&iov->dev->sriov->lock);
 
         return rc;
@@ -143,20 +135,15 @@ failed1:
 static void virtfn_remove(struct pci_dev *dev, int id, int reset)
 {
         char buf[VIRTFN_ID_LEN];
-        struct pci_bus *bus;
         struct pci_dev *virtfn;
         struct pci_sriov *iov = dev->sriov;
 
-        bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id));
-        if (!bus)
-                return;
-
-        virtfn = pci_get_slot(bus, virtfn_devfn(dev, id));
+        virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
+                                             virtfn_bus(dev, id),
+                                             virtfn_devfn(dev, id));
         if (!virtfn)
                 return;
 
-        pci_dev_put(virtfn);
-
         if (reset) {
                 device_release_driver(&virtfn->dev);
                 __pci_reset_function(virtfn);
@@ -174,9 +161,11 @@ static void virtfn_remove(struct pci_dev *dev, int id, int reset)
 
         mutex_lock(&iov->dev->sriov->lock);
         pci_stop_and_remove_bus_device(virtfn);
-        virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
+        virtfn_remove_bus(dev->bus, virtfn->bus);
         mutex_unlock(&iov->dev->sriov->lock);
 
+        /* balance pci_get_domain_bus_and_slot() */
+        pci_dev_put(virtfn);
         pci_dev_put(dev);
 }
 
@@ -333,13 +322,14 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
                 if (!pdev)
                         return -ENODEV;
 
-                pci_dev_put(pdev);
-
-                if (!pdev->is_physfn)
+                if (!pdev->is_physfn) {
+                        pci_dev_put(pdev);
                         return -ENODEV;
+                }
 
                 rc = sysfs_create_link(&dev->dev.kobj,
                                         &pdev->dev.kobj, "dep_link");
+                pci_dev_put(pdev);
                 if (rc)
                         return rc;
         }