pci_lock_rescan_remove();
- bus = eeh_pe_bus_get(pe);
+ bus = eeh_pe_bus_get_nolock(pe);
if (!bus) {
pr_err("%s: Cannot find PCI bus for PHB#%x-PE#%x\n",
__func__, pe->phb->global_number, pe->addr);
/* Log the event */
if (pe->type & EEH_PE_PHB) {
pr_err("EEH: Recovering PHB#%x, location: %s\n",
- pe->phb->global_number, eeh_pe_loc_get(pe));
+ pe->phb->global_number, eeh_pe_loc_get_bus(bus));
} else {
struct eeh_pe *phb_pe = eeh_phb_pe_get(pe->phb);
pr_err("EEH: Recovering PHB#%x-PE#%x\n",
pe->phb->global_number, pe->addr);
pr_err("EEH: PE location: %s, PHB location: %s\n",
- eeh_pe_loc_get(pe), eeh_pe_loc_get(phb_pe));
+ eeh_pe_loc_get_bus(bus),
+ eeh_pe_loc_get_bus(eeh_pe_bus_get_nolock(phb_pe)));
}
#ifdef CONFIG_STACKTRACE
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
- bus = eeh_pe_bus_get(pe);
+ bus = eeh_pe_bus_get_nolock(pe);
if (bus)
pci_hp_remove_devices(bus);
else
(phb_pe->state & EEH_PE_RECOVERING))
continue;
- bus = eeh_pe_bus_get(phb_pe);
+ bus = eeh_pe_bus_get_nolock(phb_pe);
if (!bus) {
pr_err("%s: Cannot find PCI bus for "
"PHB#%x-PE#%x\n",
const char *eeh_pe_loc_get(struct eeh_pe *pe)
{
struct pci_bus *bus = eeh_pe_bus_get(pe);
+ return eeh_pe_loc_get_bus(bus);
+}
+
+/**
+ * eeh_pe_loc_get_bus - Retrieve location code binding to the given PCI bus
+ * @bus: PCI bus
+ *
+ * Retrieve the location code associated with the given PCI bus. If the bus
+ * is a root bus, the location code is fetched from the PHB device tree node
+ * or root port. Otherwise, the location code is obtained from the device
+ * tree node of the upstream bridge of the bus. The function walks up the
+ * bus hierarchy if necessary, checking each node for the appropriate
+ * location code property ("ibm,io-base-loc-code" for root buses,
+ * "ibm,slot-location-code" for others). If no location code is found,
+ * returns "N/A".
+ */
+const char *eeh_pe_loc_get_bus(struct pci_bus *bus)
+{
struct device_node *dn;
const char *loc = NULL;
}
/**
- * eeh_pe_bus_get - Retrieve PCI bus according to the given PE
+ * _eeh_pe_bus_get - Retrieve PCI bus according to the given PE
* @pe: EEH PE
+ * @do_lock: Is the caller already held the pci_lock_rescan_remove?
*
* Retrieve the PCI bus according to the given PE. Basically,
* there're 3 types of PEs: PHB/Bus/Device. For PHB PE, the
* returned for BUS PE. However, we don't have associated PCI
* bus for DEVICE PE.
*/
-struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
+static struct pci_bus *_eeh_pe_bus_get(struct eeh_pe *pe, bool do_lock)
{
struct eeh_dev *edev;
struct pci_dev *pdev;
/* Retrieve the parent PCI bus of first (top) PCI device */
edev = list_first_entry_or_null(&pe->edevs, struct eeh_dev, entry);
- pci_lock_rescan_remove();
+ if (do_lock)
+ pci_lock_rescan_remove();
pdev = eeh_dev_to_pci_dev(edev);
if (pdev)
bus = pdev->bus;
- pci_unlock_rescan_remove();
+ if (do_lock)
+ pci_unlock_rescan_remove();
return bus;
}
+
+/**
+ * eeh_pe_bus_get - Retrieve PCI bus associated with the given EEH PE, locking
+ * if needed
+ * @pe: Pointer to the EEH PE
+ *
+ * This function is a wrapper around _eeh_pe_bus_get(), which retrieves the PCI
+ * bus associated with the provided EEH PE structure. It acquires the PCI
+ * rescans lock to ensure safe access to shared data during the retrieval
+ * process. This function should be used when the caller requires the PCI bus
+ * while holding the rescan/remove lock, typically during operations that modify
+ * or inspect PCIe device state in a safe manner.
+ *
+ * RETURNS:
+ * A pointer to the PCI bus associated with the EEH PE, or NULL if none found.
+ */
+
+struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
+{
+ return _eeh_pe_bus_get(pe, true);
+}
+
+/**
+ * eeh_pe_bus_get_nolock - Retrieve PCI bus associated with the given EEH PE
+ * without locking
+ * @pe: Pointer to the EEH PE
+ *
+ * This function is a variant of _eeh_pe_bus_get() that retrieves the PCI bus
+ * associated with the specified EEH PE without acquiring the
+ * pci_lock_rescan_remove lock. It should only be used when the caller can
+ * guarantee safe access to PE structures without the need for that lock,
+ * typically in contexts where the lock is already held locking is otherwise
+ * managed.
+ *
+ * RETURNS:
+ * pointer to the PCI bus associated with the EEH PE, or NULL if none is found.
+ *
+ * NOTE:
+ * Use this function carefully to avoid race conditions and data corruption.
+ */
+
+struct pci_bus *eeh_pe_bus_get_nolock(struct eeh_pe *pe)
+{
+ return _eeh_pe_bus_get(pe, false);
+}
projects / thirdparty / kernel / linux.git / commitdiff
