PCI: sgihp: 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 disable_slot()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 29 insertions, 34 deletions

diff --git a/drivers/pci/hotplug/sgi_hotplug.c b/drivers/pci/hotplug/sgi_hotplug.c
index f64ca92253da..14ad22e07e00 100644
--- a/drivers/pci/hotplug/sgi_hotplug.c
+++ b/drivers/pci/hotplug/sgi_hotplug.c
@@ -334,7 +334,7 @@ static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
         struct slot *slot = bss_hotplug_slot->private;
         struct pci_bus *new_bus = NULL;
         struct pci_dev *dev;
-        int func, num_funcs;
+        int num_funcs;
         int new_ppb = 0;
         int rc;
         char *ssdt = NULL;
@@ -381,29 +381,26 @@ static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
          * to the Linux PCI interface and tell the drivers
          * about them.
          */
-        for (func = 0; func < num_funcs;  func++) {
-                dev = pci_get_slot(slot->pci_bus,
-                                   PCI_DEVFN(slot->device_num + 1,
-                                             PCI_FUNC(func)));
-                if (dev) {
-                        /* Need to do slot fixup on PPB before fixup of children
-                         * (PPB's pcidev_info needs to be in pcidev_info list
-                         * before child's SN_PCIDEV_INFO() call to setup
-                         * pdi_host_pcidev_info).
-                         */
-                        pcibios_fixup_device_resources(dev);
-                        if (SN_ACPI_BASE_SUPPORT())
-                                sn_acpi_slot_fixup(dev);
-                        else
-                                sn_io_slot_fixup(dev);
-                        if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
-                                pci_hp_add_bridge(dev);
-                                if (dev->subordinate) {
-                                        new_bus = dev->subordinate;
-                                        new_ppb = 1;
-                                }
+        list_for_each_entry(dev, &slot->pci_bus->devices, bus_list) {
+                if (PCI_SLOT(dev->devfn) != slot->device_num + 1)
+                        continue;
+
+                /* Need to do slot fixup on PPB before fixup of children
+                 * (PPB's pcidev_info needs to be in pcidev_info list
+                 * before child's SN_PCIDEV_INFO() call to setup
+                 * pdi_host_pcidev_info).
+                 */
+                pcibios_fixup_device_resources(dev);
+                if (SN_ACPI_BASE_SUPPORT())
+                        sn_acpi_slot_fixup(dev);
+                else
+                        sn_io_slot_fixup(dev);
+                if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
+                        pci_hp_add_bridge(dev);
+                        if (dev->subordinate) {
+                                new_bus = dev->subordinate;
+                                new_ppb = 1;
                         }
-                        pci_dev_put(dev);
                 }
         }
 
@@ -485,8 +482,7 @@ static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
 static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
 {
         struct slot *slot = bss_hotplug_slot->private;
-        struct pci_dev *dev;
-        int func;
+        struct pci_dev *dev, *temp;
         int rc;
         acpi_owner_id ssdt_id = 0;
 
@@ -546,15 +542,14 @@ static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
         }
 
         /* Free the SN resources assigned to the Linux device.*/
-        for (func = 0; func < 8;  func++) {
-                dev = pci_get_slot(slot->pci_bus,
-                                   PCI_DEVFN(slot->device_num + 1,
-                                             PCI_FUNC(func)));
-                if (dev) {
-                        sn_bus_free_data(dev);
-                        pci_stop_and_remove_bus_device(dev);
-                        pci_dev_put(dev);
-                }
+        list_for_each_entry_safe(dev, temp, &slot->pci_bus->devices, bus_list) {
+                if (PCI_SLOT(dev->devfn) != slot->device_num + 1)
+                        continue;
+
+                pci_dev_get(dev);
+                sn_bus_free_data(dev);
+                pci_stop_and_remove_bus_device(dev);
+                pci_dev_put(dev);
         }
 
         /* Remove the SSDT for the slot from the ACPI namespace */