PCI: shpchp: Iterate over all devices in slot, not functions 0-7

Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7.  It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.

ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.

[bhelgaas: changelog, check PCI_SLOT, fix shpchp_unconfigure_device()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 16 insertions, 20 deletions

diff --git a/drivers/pci/hotplug/shpchp_pci.c b/drivers/pci/hotplug/shpchp_pci.c
index c627ed9957d1..b0e83132542e 100644
--- a/drivers/pci/hotplug/shpchp_pci.c
+++ b/drivers/pci/hotplug/shpchp_pci.c
@@ -40,7 +40,7 @@ int __ref shpchp_configure_device(struct slot *p_slot)
         struct controller *ctrl = p_slot->ctrl;
         struct pci_dev *bridge = ctrl->pci_dev;
         struct pci_bus *parent = bridge->subordinate;
-        int num, fn;
+        int num;
 
         dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, 0));
         if (dev) {
@@ -57,24 +57,20 @@ int __ref shpchp_configure_device(struct slot *p_slot)
                 return -ENODEV;
         }
 
-        for (fn = 0; fn < 8; fn++) {
-                dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, fn));
-                if (!dev)
+        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))
                         pci_hp_add_bridge(dev);
-                pci_dev_put(dev);
         }
 
         pci_assign_unassigned_bridge_resources(bridge);
 
-        for (fn = 0; fn < 8; fn++) {
-                dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, fn));
-                if (!dev)
+        list_for_each_entry(dev, &parent->devices, bus_list) {
+                if (PCI_SLOT(dev->devfn) != p_slot->device)
                         continue;
                 pci_configure_slot(dev);
-                pci_dev_put(dev);
         }
 
         pci_bus_add_devices(parent);
@@ -85,32 +81,32 @@ int __ref shpchp_configure_device(struct slot *p_slot)
 int shpchp_unconfigure_device(struct slot *p_slot)
 {
         int rc = 0;
-        int j;
         u8 bctl = 0;
         struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
+        struct pci_dev *dev, *temp;
         struct controller *ctrl = p_slot->ctrl;
 
         ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:%02x\n",
                  __func__, pci_domain_nr(parent), p_slot->bus, p_slot->device);
 
-        for (j = 0; j < 8 ; j++) {
-                struct pci_dev *temp = pci_get_slot(parent,
-                                (p_slot->device << 3) | j);
-                if (!temp)
+        list_for_each_entry_safe(dev, temp, &parent->devices, bus_list) {
+                if (PCI_SLOT(dev->devfn) != p_slot->device)
                         continue;
-                if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
-                        pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
+
+                pci_dev_get(dev);
+                if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
+                        pci_read_config_byte(dev, PCI_BRIDGE_CONTROL, &bctl);
                         if (bctl & PCI_BRIDGE_CTL_VGA) {
                                 ctrl_err(ctrl,
                                          "Cannot remove display device %s\n",
-                                         pci_name(temp));
-                                pci_dev_put(temp);
+                                         pci_name(dev));
+                                pci_dev_put(dev);
                                 rc = -EINVAL;
                                 break;
                         }
                 }
-                pci_stop_and_remove_bus_device(temp);
-                pci_dev_put(temp);
+                pci_stop_and_remove_bus_device(dev);
+                pci_dev_put(dev);
         }
         return rc;
 }