Changing the number of a bus (therefore changing addresses of this bus, of
its children and all the buses next in the tree) invalidates entries in
/sys/devices/pci*, /proc/bus/pci/* and symlinks in /sys/bus/pci/devices/*
for all the renamed devices and buses.
Remove the affected proc and sysfs entries and symlinks before renaming the
bus, then created them back.
Signed-off-by: Sergey Miroshnichenko <s.miroshnichenko@xxxxxxxxx>
---
drivers/pci/probe.c | 105 +++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 104 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index be9e5754cac7..fe9bf012ef33 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1096,12 +1096,99 @@ static void pci_enable_crs(struct pci_dev *pdev)
PCI_EXP_RTCTL_CRSSVE);
}
+static void pci_buses_remove_sysfs(int domain, int busnr, int max_bus_number)
+{
+ struct pci_bus *bus;
+ struct pci_dev *dev = NULL;
+
+ bus = pci_find_bus(domain, busnr);
+ if (!bus)
+ return;
+
+ if (busnr < max_bus_number)
+ pci_buses_remove_sysfs(domain, busnr + 1, max_bus_number);
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ device_remove_class_symlinks(&dev->dev);
+ pci_remove_sysfs_dev_files(dev);
+ pci_proc_detach_device(dev);
+ bus_disconnect_device(&dev->dev);
+ }
+
+ device_remove_class_symlinks(&bus->dev);
+ pci_proc_detach_bus(bus);
+}
+
+static void pci_buses_create_sysfs(int domain, int busnr, int max_bus_number)
+{
+ struct pci_bus *bus;
+ struct pci_dev *dev = NULL;
+
+ bus = pci_find_bus(domain, busnr);
+ if (!bus)
+ return;
+
+ device_add_class_symlinks(&bus->dev);
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ bus_add_device(&dev->dev);
+ if (pci_dev_is_added(dev)) {
+ pci_proc_attach_device(dev);
+ pci_create_sysfs_dev_files(dev);
+ device_add_class_symlinks(&dev->dev);
+ }
+ }
+
+ if (busnr < max_bus_number)
+ pci_buses_create_sysfs(domain, busnr + 1, max_bus_number);
+}
+
+static void pci_rename_bus(struct pci_bus *bus, const char *new_bus_name)
+{
+ struct class *class;
+ int err;
+
+ class = bus->dev.class;
+ bus->dev.class = NULL;
+ err = device_rename(&bus->dev, new_bus_name);
+ bus->dev.class = class;
+}
+
+static void pci_rename_bus_devices(struct pci_bus *bus, const int domain,
+ const int new_busnr)
+{
+ struct pci_dev *dev = NULL;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ char old_name[64];
+ char new_name[64];
+ struct class *class;
+ int err;
+ int i;
+
+ strncpy(old_name, dev_name(&dev->dev), sizeof(old_name));
+ sprintf(new_name, "%04x:%02x:%02x.%d", domain, new_busnr,
+ PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
+ class = dev->dev.class;
+ dev->dev.class = NULL;
+ err = device_rename(&dev->dev, new_name);
+ dev->dev.class = class;
+
+ for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
+ dev->resource[i].name = pci_name(dev);
+ }
+}
+
static void pci_do_move_buses(const int domain, int busnr, int first_moved_busnr,
int delta, const struct resource *valid_range)
{
struct pci_bus *bus;
- int subordinate;
+ int subordinate, old_primary;
u32 old_buses, buses;
+ char old_bus_name[64];
+ char new_bus_name[64];
+ struct resource old_res;
+ int new_busnr = busnr + delta;
if (busnr < valid_range->start || busnr > valid_range->end)
return;
@@ -1110,11 +1197,21 @@ static void pci_do_move_buses(const int domain, int busnr, int first_moved_busnr
if (!bus)
return;
+ old_primary = bus->primary;
+ strncpy(old_bus_name, dev_name(&bus->dev), sizeof(old_bus_name));
+ sprintf(new_bus_name, "%04x:%02x", domain, new_busnr);
+
if (delta > 0) {
pci_do_move_buses(domain, busnr + 1, first_moved_busnr,
delta, valid_range);
+ pci_rename_bus_devices(bus, domain, new_busnr);
+ pci_rename_bus(bus, new_bus_name);
+ } else {
+ pci_rename_bus(bus, new_bus_name);
+ pci_rename_bus_devices(bus, domain, new_busnr);
}
+ memcpy(&old_res, &bus->busn_res, sizeof(old_res));
bus->number += delta;
bus->busn_res.start += delta;
@@ -1132,6 +1229,10 @@ static void pci_do_move_buses(const int domain, int busnr, int first_moved_busnr
buses |= (unsigned int)(subordinate << 16);
pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
+ dev_warn(&bus->dev, "Renamed bus %s (%02x-%pR) to %s (%02x-%pR)\n",
+ old_bus_name, old_primary, &old_res,
+ new_bus_name, bus->primary, &bus->busn_res);
+
if (delta < 0)
pci_do_move_buses(domain, busnr + 1, first_moved_busnr,
delta, valid_range);
@@ -1192,8 +1293,10 @@ static int pci_move_buses(int domain, int busnr, int delta,
}
}
+ pci_buses_remove_sysfs(domain, busnr, valid_range->end);
pci_do_move_buses(domain, busnr, busnr,
delta, valid_range);
+ pci_buses_create_sysfs(domain, busnr + delta, valid_range->end);
return 0;
}
--
2.23.0
