22 files changed, 154 insertions, 45 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index ab8d76dfaa80..6615fda0abfb 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -250,3 +250,24 @@ Description:
                 valid.  For example, writing a 2 to this file when sriov_numvfs
                 is not 0 and not 2 already will return an error. Writing a 10
                 when the value of sriov_totalvfs is 8 will return an error.
+
+What:           /sys/bus/pci/devices/.../driver_override
+Date:           April 2014
+Contact:        Alex Williamson <alex.williamson@redhat.com>
+Description:
+                This file allows the driver for a device to be specified which
+                will override standard static and dynamic ID matching.  When
+                specified, only a driver with a name matching the value written
+                to driver_override will have an opportunity to bind to the
+                device.  The override is specified by writing a string to the
+                driver_override file (echo pci-stub > driver_override) and
+                may be cleared with an empty string (echo > driver_override).
+                This returns the device to standard matching rules binding.
+                Writing to driver_override does not automatically unbind the
+                device from its current driver or make any attempt to
+                automatically load the specified driver.  If no driver with a
+                matching name is currently loaded in the kernel, the device
+                will not bind to any driver.  This also allows devices to
+                opt-out of driver binding using a driver_override name such as
+                "none".  Only a single driver may be specified in the override,
+                there is no support for parsing delimiters.
diff --git a/arch/ia64/pci/fixup.c b/arch/ia64/pci/fixup.c
index eee069a0b539..1fe9aa5068ea 100644
--- a/arch/ia64/pci/fixup.c
+++ b/arch/ia64/pci/fixup.c
@@ -49,9 +49,7 @@ static void pci_fixup_video(struct pci_dev *pdev)
                  * type BRIDGE, or CARDBUS. Host to PCI controllers use
                  * PCI header type NORMAL.
                  */
-                if (bridge
-                    &&((bridge->hdr_type == PCI_HEADER_TYPE_BRIDGE)
-                       ||(bridge->hdr_type == PCI_HEADER_TYPE_CARDBUS))) {
+                if (bridge && (pci_is_bridge(bridge))) {
                         pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
                                                 &config);
                         if (!(config & PCI_BRIDGE_CTL_VGA))
diff --git a/arch/powerpc/kernel/pci-hotplug.c b/arch/powerpc/kernel/pci-hotplug.c
index c1e17ae68a08..5b789177aa29 100644
--- a/arch/powerpc/kernel/pci-hotplug.c
+++ b/arch/powerpc/kernel/pci-hotplug.c
@@ -98,8 +98,7 @@ void pcibios_add_pci_devices(struct pci_bus * bus)
                 max = bus->busn_res.start;
                 for (pass = 0; pass < 2; pass++) {
                         list_for_each_entry(dev, &bus->devices, bus_list) {
-                                if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-                                    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+                                if (pci_is_bridge(dev))
                                         max = pci_scan_bridge(bus, dev,
                                                               max, pass);
                         }
diff --git a/arch/powerpc/kernel/pci_of_scan.c b/arch/powerpc/kernel/pci_of_scan.c
index 83c26d829991..059e244484fe 100644
--- a/arch/powerpc/kernel/pci_of_scan.c
+++ b/arch/powerpc/kernel/pci_of_scan.c
@@ -362,8 +362,7 @@ static void __of_scan_bus(struct device_node *node, struct pci_bus *bus,
 
         /* Now scan child busses */
         list_for_each_entry(dev, &bus->devices, bus_list) {
-                if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-                    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
+                if (pci_is_bridge(dev)) {
                         of_scan_pci_bridge(dev);
                 }
         }
diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index 1555bbcae1ee..857ad77df9c0 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -543,8 +543,7 @@ static void pci_of_scan_bus(struct pci_pbm_info *pbm,
                         printk("PCI: dev header type: %x\n",
                                dev->hdr_type);
 
-                if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-                    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+                if (pci_is_bridge(dev))
                         of_scan_pci_bridge(pbm, child, dev);
         }
 }
diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
index ef334a003f3c..b5e60268d93f 100644
--- a/arch/x86/pci/fixup.c
+++ b/arch/x86/pci/fixup.c
@@ -338,9 +338,7 @@ static void pci_fixup_video(struct pci_dev *pdev)
                  * type BRIDGE, or CARDBUS. Host to PCI controllers use
                  * PCI header type NORMAL.
                  */
-                if (bridge
-                    && ((bridge->hdr_type == PCI_HEADER_TYPE_BRIDGE)
-                       || (bridge->hdr_type == PCI_HEADER_TYPE_CARDBUS))) {
+                if (bridge && (pci_is_bridge(bridge))) {
                         pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
                                                 &config);
                         if (!(config & PCI_BRIDGE_CTL_VGA))
diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 7c64fa756cce..a842c71dcc21 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -2775,6 +2775,16 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
         return result;
 }
 
+static void nvme_reset_notify(struct pci_dev *pdev, bool prepare)
+{
+       struct nvme_dev *dev = pci_get_drvdata(pdev);
+
+       if (prepare)
+               nvme_dev_shutdown(dev);
+       else
+               nvme_dev_resume(dev);
+}
+
 static void nvme_shutdown(struct pci_dev *pdev)
 {
         struct nvme_dev *dev = pci_get_drvdata(pdev);
@@ -2839,6 +2849,7 @@ static const struct pci_error_handlers nvme_err_handler = {
         .link_reset     = nvme_link_reset,
         .slot_reset     = nvme_slot_reset,
         .resume         = nvme_error_resume,
+        .reset_notify   = nvme_reset_notify,
 };
 
 /* Move to pci_ids.h later */
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index bb945e33b1ec..75e178330215 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -515,8 +515,7 @@ static void enable_slot(struct acpiphp_slot *slot)
                         if (PCI_SLOT(dev->devfn) != slot->device)
                                 continue;
 
-                        if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-                            dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
+                        if (pci_is_bridge(dev)) {
                                 max = pci_scan_bridge(bus, dev, max, pass);
                                 if (pass && dev->subordinate) {
                                         check_hotplug_bridge(slot, dev);
diff --git a/drivers/pci/hotplug/cpci_hotplug_pci.c b/drivers/pci/hotplug/cpci_hotplug_pci.c
index b238a1a28372..f6ef64c2ccb5 100644
--- a/drivers/pci/hotplug/cpci_hotplug_pci.c
+++ b/drivers/pci/hotplug/cpci_hotplug_pci.c
@@ -289,8 +289,7 @@ int cpci_configure_slot(struct slot *slot)
         list_for_each_entry(dev, &parent->devices, bus_list)
                 if (PCI_SLOT(dev->devfn) != PCI_SLOT(slot->devfn))
                         continue;
-                if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
-                    (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS))
+                if (pci_is_bridge(dev))
                         pci_hp_add_bridge(dev);
 
 
diff --git a/drivers/pci/hotplug/cpqphp_ctrl.c b/drivers/pci/hotplug/cpqphp_ctrl.c
index 11845b796799..f593585f2784 100644
--- a/drivers/pci/hotplug/cpqphp_ctrl.c
+++ b/drivers/pci/hotplug/cpqphp_ctrl.c
@@ -709,7 +709,8 @@ static struct pci_resource *get_max_resource(struct pci_resource **head, u32 siz
                                 temp = temp->next;
                         }
 
-                        temp->next = max->next;
+                        if (temp)
+                                temp->next = max->next;
                 }
 
                 max->next = NULL;
diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index 1b533060ce65..b6cb1df67097 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -62,8 +62,7 @@ int pciehp_configure_device(struct slot *p_slot)
         }
 
         list_for_each_entry(dev, &parent->devices, bus_list)
-                if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
-                                (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS))
+                if (pci_is_bridge(dev))
                         pci_hp_add_bridge(dev);
 
         pci_assign_unassigned_bridge_resources(bridge);
diff --git a/drivers/pci/hotplug/rpadlpar_core.c b/drivers/pci/hotplug/rpadlpar_core.c
index 4fcdeedda31b..7660232ef460 100644
--- a/drivers/pci/hotplug/rpadlpar_core.c
+++ b/drivers/pci/hotplug/rpadlpar_core.c
@@ -157,8 +157,7 @@ static void dlpar_pci_add_bus(struct device_node *dn)
         }
 
         /* Scan below the new bridge */
-        if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-            dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+        if (pci_is_bridge(dev))
                 of_scan_pci_bridge(dev);
 
         /* Map IO space for child bus, which may or may not succeed */
diff --git a/drivers/pci/hotplug/shpchp_pci.c b/drivers/pci/hotplug/shpchp_pci.c
index 18209ebc0979..9202d133485c 100644
--- a/drivers/pci/hotplug/shpchp_pci.c
+++ b/drivers/pci/hotplug/shpchp_pci.c
@@ -64,8 +64,7 @@ int shpchp_configure_device(struct slot *p_slot)
         list_for_each_entry(dev, &parent->devices, bus_list) {
                 if (PCI_SLOT(dev->devfn) != p_slot->device)
                         continue;
-                if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
-                    (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS))
+                if (pci_is_bridge(dev))
                         pci_hp_add_bridge(dev);
         }
 
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index f49abef88485..ca4927ba8433 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -309,13 +309,7 @@ static struct acpi_device *acpi_pci_find_companion(struct device *dev)
         bool check_children;
         u64 addr;
 
-        /*
-         * pci_is_bridge() is not suitable here, because pci_dev->subordinate
-         * is set only after acpi_pci_find_device() has been called for the
-         * given device.
-         */
-        check_children = pci_dev->hdr_type == PCI_HEADER_TYPE_BRIDGE
-                        || pci_dev->hdr_type == PCI_HEADER_TYPE_CARDBUS;
+        check_children = pci_is_bridge(pci_dev);
         /* Please ref to ACPI spec for the syntax of _ADR */
         addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
         return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index ff236ed4f5cf..837d71f5390b 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -236,6 +236,13 @@ const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
         return NULL;
 }
 
+static const struct pci_device_id pci_device_id_any = {
+        .vendor = PCI_ANY_ID,
+        .device = PCI_ANY_ID,
+        .subvendor = PCI_ANY_ID,
+        .subdevice = PCI_ANY_ID,
+};
+
 /**
  * pci_match_device - Tell if a PCI device structure has a matching PCI device id structure
  * @drv: the PCI driver to match against
@@ -249,18 +256,30 @@ static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
                                                     struct pci_dev *dev)
 {
         struct pci_dynid *dynid;
+        const struct pci_device_id *found_id = NULL;
+
+        /* When driver_override is set, only bind to the matching driver */
+        if (dev->driver_override && strcmp(dev->driver_override, drv->name))
+                return NULL;
 
         /* Look at the dynamic ids first, before the static ones */
         spin_lock(&drv->dynids.lock);
         list_for_each_entry(dynid, &drv->dynids.list, node) {
                 if (pci_match_one_device(&dynid->id, dev)) {
-                        spin_unlock(&drv->dynids.lock);
-                        return &dynid->id;
+                        found_id = &dynid->id;
+                        break;
                 }
         }
         spin_unlock(&drv->dynids.lock);
 
-        return pci_match_id(drv->id_table, dev);
+        if (!found_id)
+                found_id = pci_match_id(drv->id_table, dev);
+
+        /* driver_override will always match, send a dummy id */
+        if (!found_id && dev->driver_override)
+                found_id = &pci_device_id_any;
+
+        return found_id;
 }
 
 struct drv_dev_and_id {
@@ -600,14 +619,14 @@ static void pci_pm_default_resume(struct pci_dev *pci_dev)
 {
         pci_fixup_device(pci_fixup_resume, pci_dev);
 
-        if (!pci_is_bridge(pci_dev))
+        if (!pci_has_subordinate(pci_dev))
                 pci_enable_wake(pci_dev, PCI_D0, false);
 }
 
 static void pci_pm_default_suspend(struct pci_dev *pci_dev)
 {
         /* Disable non-bridge devices without PM support */
-        if (!pci_is_bridge(pci_dev))
+        if (!pci_has_subordinate(pci_dev))
                 pci_disable_enabled_device(pci_dev);
 }
 
@@ -737,7 +756,7 @@ static int pci_pm_suspend_noirq(struct device *dev)
 
         if (!pci_dev->state_saved) {
                 pci_save_state(pci_dev);
-                if (!pci_is_bridge(pci_dev))
+                if (!pci_has_subordinate(pci_dev))
                         pci_prepare_to_sleep(pci_dev);
         }
 
@@ -991,7 +1010,7 @@ static int pci_pm_poweroff_noirq(struct device *dev)
                         return error;
         }
 
-        if (!pci_dev->state_saved && !pci_is_bridge(pci_dev))
+        if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
                 pci_prepare_to_sleep(pci_dev);
 
         /*
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index b7333fa5f80d..84c350994b06 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -514,6 +514,45 @@ static struct device_attribute sriov_numvfs_attr =
                        sriov_numvfs_show, sriov_numvfs_store);
 #endif /* CONFIG_PCI_IOV */
 
+static ssize_t driver_override_store(struct device *dev,
+                                     struct device_attribute *attr,
+                                     const char *buf, size_t count)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+        char *driver_override, *old = pdev->driver_override, *cp;
+
+        if (count > PATH_MAX)
+                return -EINVAL;
+
+        driver_override = kstrndup(buf, count, GFP_KERNEL);
+        if (!driver_override)
+                return -ENOMEM;
+
+        cp = strchr(driver_override, '\n');
+        if (cp)
+                *cp = '\0';
+
+        if (strlen(driver_override)) {
+                pdev->driver_override = driver_override;
+        } else {
+                kfree(driver_override);
+                pdev->driver_override = NULL;
+        }
+
+        kfree(old);
+
+        return count;
+}
+
+static ssize_t driver_override_show(struct device *dev,
+                                    struct device_attribute *attr, char *buf)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+
+        return sprintf(buf, "%s\n", pdev->driver_override);
+}
+static DEVICE_ATTR_RW(driver_override);
+
 static struct attribute *pci_dev_attrs[] = {
         &dev_attr_resource.attr,
         &dev_attr_vendor.attr,
@@ -539,6 +578,7 @@ static struct attribute *pci_dev_attrs[] = {
 #ifdef CONFIG_OF
         &dev_attr_devspec.attr,
 #endif
+        &dev_attr_driver_override.attr,
         NULL,
 };
 
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 39012831867e..f988bb18eba5 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3305,8 +3305,27 @@ static void pci_dev_unlock(struct pci_dev *dev)
         pci_cfg_access_unlock(dev);
 }
 
+/**
+ * pci_reset_notify - notify device driver of reset
+ * @dev: device to be notified of reset
+ * @prepare: 'true' if device is about to be reset; 'false' if reset attempt
+ *           completed
+ *
+ * Must be called prior to device access being disabled and after device
+ * access is restored.
+ */
+static void pci_reset_notify(struct pci_dev *dev, bool prepare)
+{
+        const struct pci_error_handlers *err_handler =
+                        dev->driver ? dev->driver->err_handler : NULL;
+        if (err_handler && err_handler->reset_notify)
+                err_handler->reset_notify(dev, prepare);
+}
+
 static void pci_dev_save_and_disable(struct pci_dev *dev)
 {
+        pci_reset_notify(dev, true);
+
         /*
          * Wake-up device prior to save.  PM registers default to D0 after
          * reset and a simple register restore doesn't reliably return
@@ -3328,6 +3347,7 @@ static void pci_dev_save_and_disable(struct pci_dev *dev)
 static void pci_dev_restore(struct pci_dev *dev)
 {
         pci_restore_state(dev);
+        pci_reset_notify(dev, false);
 }
 
 static int pci_dev_reset(struct pci_dev *dev, int probe)
@@ -3344,6 +3364,7 @@ static int pci_dev_reset(struct pci_dev *dev, int probe)
 
         return rc;
 }
+
 /**
  * __pci_reset_function - reset a PCI device function
  * @dev: PCI device to reset
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index fe233a3099cf..0601890db22d 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -77,7 +77,7 @@ static inline void pci_wakeup_event(struct pci_dev *dev)
         pm_wakeup_event(&dev->dev, 100);
 }
 
-static inline bool pci_is_bridge(struct pci_dev *pci_dev)
+static inline bool pci_has_subordinate(struct pci_dev *pci_dev)
 {
         return !!(pci_dev->subordinate);
 }
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 52d05e054cd8..36f1fd174b07 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1225,6 +1225,7 @@ static void pci_release_dev(struct device *dev)
         pci_release_of_node(pci_dev);
         pcibios_release_device(pci_dev);
         pci_bus_put(pci_dev->bus);
+        kfree(pci_dev->driver_override);
         kfree(pci_dev);
 }
 
@@ -1680,8 +1681,7 @@ unsigned int pci_scan_child_bus(struct pci_bus *bus)
 
         for (pass=0; pass < 2; pass++)
                 list_for_each_entry(dev, &bus->devices, bus_list) {
-                        if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-                            dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+                        if (pci_is_bridge(dev))
                                 max = pci_scan_bridge(bus, dev, max, pass);
                 }
 
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index d9fdcea4412a..fd9b545c3cf5 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1716,9 +1716,7 @@ void pci_assign_unassigned_bus_resources(struct pci_bus *bus)
 
         down_read(&pci_bus_sem);
         list_for_each_entry(dev, &bus->devices, bus_list)
-                if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-                    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
-                        if (dev->subordinate)
+                if (pci_is_bridge(dev) && pci_has_subordinate(dev))
                                 __pci_bus_size_bridges(dev->subordinate,
                                                          &add_list);
         up_read(&pci_bus_sem);
diff --git a/drivers/pcmcia/cardbus.c b/drivers/pcmcia/cardbus.c
index 8bde61952d20..4fe4cc4ae19a 100644
--- a/drivers/pcmcia/cardbus.c
+++ b/drivers/pcmcia/cardbus.c
@@ -78,8 +78,7 @@ int __ref cb_alloc(struct pcmcia_socket *s)
         max = bus->busn_res.start;
         for (pass = 0; pass < 2; pass++)
                 list_for_each_entry(dev, &bus->devices, bus_list)
-                        if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-                            dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+                        if (pci_is_bridge(dev))
                                 max = pci_scan_bridge(bus, dev, max, pass);
 
         /*
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 5dbd15422b55..4eb99966570e 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -365,6 +365,7 @@ struct pci_dev {
 #endif
         phys_addr_t rom; /* Physical address of ROM if it's not from the BAR */
         size_t romlen; /* Length of ROM if it's not from the BAR */
+        char *driver_override; /* Driver name to force a match */
 };
 
 static inline struct pci_dev *pci_physfn(struct pci_dev *dev)
@@ -477,6 +478,19 @@ static inline bool pci_is_root_bus(struct pci_bus *pbus)
         return !(pbus->parent);
 }
 
+/**
+ * pci_is_bridge - check if the PCI device is a bridge
+ * @dev: PCI device
+ *
+ * Return true if the PCI device is bridge whether it has subordinate
+ * or not.
+ */
+static inline bool pci_is_bridge(struct pci_dev *dev)
+{
+        return dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
+                dev->hdr_type == PCI_HEADER_TYPE_CARDBUS;
+}
+
 static inline struct pci_dev *pci_upstream_bridge(struct pci_dev *dev)
 {
         dev = pci_physfn(dev);
@@ -603,6 +617,9 @@ struct pci_error_handlers {
         /* PCI slot has been reset */
         pci_ers_result_t (*slot_reset)(struct pci_dev *dev);
 
+        /* PCI function reset prepare or completed */
+        void (*reset_notify)(struct pci_dev *dev, bool prepare);
+
         /* Device driver may resume normal operations */
         void (*resume)(struct pci_dev *dev);
 };