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

6 files changed, 90 insertions, 74 deletions

diff --git a/drivers/char/agp/alpha-agp.c b/drivers/char/agp/alpha-agp.c
index dd84af4d4f7e..199b8e99f7d7 100644
--- a/drivers/char/agp/alpha-agp.c
+++ b/drivers/char/agp/alpha-agp.c
@@ -174,7 +174,7 @@ alpha_core_agp_setup(void)
         /*
          * Build a fake pci_dev struct
          */
-        pdev = alloc_pci_dev();
+        pdev = pci_alloc_dev(NULL);
         if (!pdev)
                 return -ENOMEM;
         pdev->vendor = 0xffff;
diff --git a/drivers/char/agp/parisc-agp.c b/drivers/char/agp/parisc-agp.c
index 94821ab01c6d..bf5d2477cb77 100644
--- a/drivers/char/agp/parisc-agp.c
+++ b/drivers/char/agp/parisc-agp.c
@@ -333,7 +333,7 @@ parisc_agp_setup(void __iomem *ioc_hpa, void __iomem *lba_hpa)
         struct agp_bridge_data *bridge;
         int error = 0;
 
-        fake_bridge_dev = alloc_pci_dev();
+        fake_bridge_dev = pci_alloc_dev(NULL);
         if (!fake_bridge_dev) {
                 error = -ENOMEM;
                 goto fail;
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 32e66a6f12d9..b1ff02ab4f13 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -283,6 +283,21 @@ void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
 }
 EXPORT_SYMBOL_GPL(pci_walk_bus);
 
+struct pci_bus *pci_bus_get(struct pci_bus *bus)
+{
+        if (bus)
+                get_device(&bus->dev);
+        return bus;
+}
+EXPORT_SYMBOL(pci_bus_get);
+
+void pci_bus_put(struct pci_bus *bus)
+{
+        if (bus)
+                put_device(&bus->dev);
+}
+EXPORT_SYMBOL(pci_bus_put);
+
 EXPORT_SYMBOL(pci_bus_alloc_resource);
 EXPORT_SYMBOL_GPL(pci_bus_add_device);
 EXPORT_SYMBOL(pci_bus_add_devices);
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;
         }
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index d0c33aac768e..46ada5c098eb 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -470,33 +470,46 @@ void pci_read_bridge_bases(struct pci_bus *child)
         }
 }
 
-static struct pci_bus * pci_alloc_bus(void)
+static struct pci_bus *pci_alloc_bus(void)
 {
         struct pci_bus *b;
 
         b = kzalloc(sizeof(*b), GFP_KERNEL);
-        if (b) {
-                INIT_LIST_HEAD(&b->node);
-                INIT_LIST_HEAD(&b->children);
-                INIT_LIST_HEAD(&b->devices);
-                INIT_LIST_HEAD(&b->slots);
-                INIT_LIST_HEAD(&b->resources);
-                b->max_bus_speed = PCI_SPEED_UNKNOWN;
-                b->cur_bus_speed = PCI_SPEED_UNKNOWN;
-        }
+        if (!b)
+                return NULL;
+
+        INIT_LIST_HEAD(&b->node);
+        INIT_LIST_HEAD(&b->children);
+        INIT_LIST_HEAD(&b->devices);
+        INIT_LIST_HEAD(&b->slots);
+        INIT_LIST_HEAD(&b->resources);
+        b->max_bus_speed = PCI_SPEED_UNKNOWN;
+        b->cur_bus_speed = PCI_SPEED_UNKNOWN;
         return b;
 }
 
+static void pci_release_host_bridge_dev(struct device *dev)
+{
+        struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
+
+        if (bridge->release_fn)
+                bridge->release_fn(bridge);
+
+        pci_free_resource_list(&bridge->windows);
+
+        kfree(bridge);
+}
+
 static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
 {
         struct pci_host_bridge *bridge;
 
         bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
-        if (bridge) {
-                INIT_LIST_HEAD(&bridge->windows);
-                bridge->bus = b;
-        }
+        if (!bridge)
+                return NULL;
 
+        INIT_LIST_HEAD(&bridge->windows);
+        bridge->bus = b;
         return bridge;
 }
 
@@ -1152,6 +1165,7 @@ static void pci_release_dev(struct device *dev)
         pci_release_capabilities(pci_dev);
         pci_release_of_node(pci_dev);
         pcibios_release_device(pci_dev);
+        pci_bus_put(pci_dev->bus);
         kfree(pci_dev);
 }
 
@@ -1208,19 +1222,7 @@ int pci_cfg_space_size(struct pci_dev *dev)
         return PCI_CFG_SPACE_SIZE;
 }
 
-static void pci_release_bus_bridge_dev(struct device *dev)
-{
-        struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
-
-        if (bridge->release_fn)
-                bridge->release_fn(bridge);
-
-        pci_free_resource_list(&bridge->windows);
-
-        kfree(bridge);
-}
-
-struct pci_dev *alloc_pci_dev(void)
+struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
 {
         struct pci_dev *dev;
 
@@ -1230,9 +1232,16 @@ struct pci_dev *alloc_pci_dev(void)
 
         INIT_LIST_HEAD(&dev->bus_list);
         dev->dev.type = &pci_dev_type;
+        dev->bus = pci_bus_get(bus);
 
         return dev;
 }
+EXPORT_SYMBOL(pci_alloc_dev);
+
+struct pci_dev *alloc_pci_dev(void)
+{
+        return pci_alloc_dev(NULL);
+}
 EXPORT_SYMBOL(alloc_pci_dev);
 
 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
@@ -1283,11 +1292,10 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
         if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
                 return NULL;
 
-        dev = alloc_pci_dev();
+        dev = pci_alloc_dev(bus);
         if (!dev)
                 return NULL;
 
-        dev->bus = bus;
         dev->devfn = devfn;
         dev->vendor = l & 0xffff;
         dev->device = (l >> 16) & 0xffff;
@@ -1295,6 +1303,7 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
         pci_set_of_node(dev);
 
         if (pci_setup_device(dev)) {
+                pci_bus_put(dev->bus);
                 kfree(dev);
                 return NULL;
         }
@@ -1720,15 +1729,19 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
                 goto err_out;
 
         bridge->dev.parent = parent;
-        bridge->dev.release = pci_release_bus_bridge_dev;
+        bridge->dev.release = pci_release_host_bridge_dev;
         dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
         error = pcibios_root_bridge_prepare(bridge);
-        if (error)
-                goto bridge_dev_reg_err;
+        if (error) {
+                kfree(bridge);
+                goto err_out;
+        }
 
         error = device_register(&bridge->dev);
-        if (error)
-                goto bridge_dev_reg_err;
+        if (error) {
+                put_device(&bridge->dev);
+                goto err_out;
+        }
         b->bridge = get_device(&bridge->dev);
         device_enable_async_suspend(b->bridge);
         pci_set_bus_of_node(b);
@@ -1784,8 +1797,6 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
 class_dev_reg_err:
         put_device(&bridge->dev);
         device_unregister(&bridge->dev);
-bridge_dev_reg_err:
-        kfree(bridge);
 err_out:
         kfree(b);
         return NULL;
diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index 846f475f62c1..90c95a3385d1 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -2026,7 +2026,7 @@ megaraid_abort_and_reset(adapter_t *adapter, Scsi_Cmnd *cmd, int aor)
 static inline int
 make_local_pdev(adapter_t *adapter, struct pci_dev **pdev)
 {
-        *pdev = alloc_pci_dev();
+        *pdev = pci_alloc_dev(NULL);
 
         if( *pdev == NULL ) return -1;