PCI/AER: Rationalize error status register clearing

commit 894020fdd8 upstream.

Conflicts:
  - Minor refractor due to code differences, Thanks to Katrin
  - Introduce an compact helper in include/linux/aer
    Too many 3rd part modules depend on this symbol, it can break
    easily later if we drop in some other modules, so use a
    function as alias. We may make is a GPL_SYMBOL later.

The AER interfaces to clear error status registers were a confusing mess:

	- pci_cleanup_aer_uncorrect_error_status() cleared non-fatal errors
	from the Uncorrectable Error Status register.

	- pci_aer_clear_fatal_status() cleared fatal errors from the
	Uncorrectable Error Status register.

	- pci_cleanup_aer_error_status_regs() cleared the Root Error Status
	register (for Root Ports), the Uncorrectable Error Status register,
	and the Correctable Error Status register.

Rename them to make them consistent:

	From                                     To
	---------------------------------------- -------------------------------
	pci_cleanup_aer_uncorrect_error_status() pci_aer_clear_nonfatal_status()
	pci_aer_clear_fatal_status()             pci_aer_clear_fatal_status()
	pci_cleanup_aer_error_status_regs()      pci_aer_clear_status()

Since pci_cleanup_aer_error_status_regs() (renamed to
pci_aer_clear_status()) is only used within drivers/pci/, move the
declaration from <linux/aer.h> to drivers/pci/pci.h.

[bhelgaas: commit log, add renames]
Link: https://lore.kernel.org/r/d1310a75dc3d28f7e8da4e99c45fbd3e60fe238e.1585000084.git.sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Xinghui Li <korantli@tencent.com>

Documentation/PCI/pcieaer-howto.rst

@@ -232,9 +232,9 @@ messages to root port when an error is detected.
 
 ::
 
-  int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev);`
+  int pci_aer_clear_nonfatal_status(struct pci_dev *dev);`
 
-pci_cleanup_aer_uncorrect_error_status cleanups the uncorrectable
+pci_aer_clear_nonfatal_status clears non-fatal errors in the uncorrectable
 error status register.
 
 Frequent Asked Questions

drivers/net/ethernet/intel/ice/ice_main.c

@@ -6601,7 +6601,7 @@ static pci_ers_result_t ice_pci_err_slot_reset(struct pci_dev *pdev)
 
 	err = pci_aer_clear_nonfatal_status(pdev);
 	if (err)
-		dev_dbg(&pdev->dev, "pci_aer_clear_nonfatal_status failed, error %d\n",
+		dev_dbg(&pdev->dev, "pci_aer_clear_nonfatal_status() failed, error %d\n",
 			err);
 		/* non-fatal, continue */
 

drivers/ntb/hw/idt/ntb_hw_idt.c

@@ -2674,8 +2674,8 @@ static int idt_init_pci(struct idt_ntb_dev *ndev)
 	ret = pci_enable_pcie_error_reporting(pdev);
 	if (ret != 0)
 		dev_warn(&pdev->dev, "PCIe AER capability disabled\n");
-	else /* Cleanup uncorrectable error status before getting to init */
-		pci_cleanup_aer_uncorrect_error_status(pdev);
+	else /* Cleanup nonfatal error status before getting to init */
+		pci_aer_clear_nonfatal_status(pdev);
 
 	/* First enable the PCI device */
 	ret = pcim_enable_device(pdev);

drivers/pci/pci.c

@@ -1472,7 +1472,7 @@ void pci_restore_state(struct pci_dev *dev)
 	pci_restore_rebar_state(dev);
 	pci_restore_dpc_state(dev);
 
-	pci_cleanup_aer_error_status_regs(dev);
+	pci_aer_clear_status(dev);
 	pci_restore_aer_state(dev);
 
 	pci_restore_config_space(dev);

drivers/pci/pci.h

@@ -670,12 +670,14 @@ void pci_aer_exit(struct pci_dev *dev);
 extern const struct attribute_group aer_stats_attr_group;
 void pci_aer_clear_fatal_status(struct pci_dev *dev);
 void pci_aer_clear_device_status(struct pci_dev *dev);
+int pci_aer_clear_status(struct pci_dev *dev);
 #else
 static inline void pci_no_aer(void) { }
 static inline void pci_aer_init(struct pci_dev *d) { }
 static inline void pci_aer_exit(struct pci_dev *d) { }
 static inline void pci_aer_clear_fatal_status(struct pci_dev *dev) { }
 static inline void pci_aer_clear_device_status(struct pci_dev *dev) { }
+static inline int pci_aer_clear_status(struct pci_dev *dev) { return -EINVAL; }
 #endif
 
 #ifdef CONFIG_ACPI

drivers/pci/pcie/aer.c

@@ -377,7 +377,7 @@ void pci_aer_clear_device_status(struct pci_dev *dev)
 	pcie_capability_write_word(dev, PCI_EXP_DEVSTA, sta);
 }
 
-int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev)
+int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
 {
 	int pos;
 	u32 status, sev;
@@ -398,7 +398,7 @@ int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev)
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(pci_cleanup_aer_uncorrect_error_status);
+EXPORT_SYMBOL_GPL(pci_aer_clear_nonfatal_status);
 
 void pci_aer_clear_fatal_status(struct pci_dev *dev)
 {
@@ -420,7 +420,7 @@ void pci_aer_clear_fatal_status(struct pci_dev *dev)
 		pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
 }
 
-int pci_cleanup_aer_error_status_regs(struct pci_dev *dev)
+int pci_aer_clear_status(struct pci_dev *dev)
 {
 	int pos;
 	u32 status;
@@ -516,7 +516,7 @@ void pci_aer_init(struct pci_dev *dev)
 	n = pcie_cap_has_rtctl(dev) ? 5 : 4;
 	pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_ERR, sizeof(u32) * n);
 
-	pci_cleanup_aer_error_status_regs(dev);
+	pci_aer_clear_status(dev);
 }
 
 void pci_aer_exit(struct pci_dev *dev)

drivers/pci/pcie/dpc.c

@@ -221,7 +221,7 @@ void dpc_process_error(struct pci_dev *pdev)
 		 dpc_get_aer_uncorrect_severity(pdev, &info) &&
 		 aer_get_device_error_info(pdev, &info)) {
 		aer_print_error(pdev, &info);
-		pci_cleanup_aer_uncorrect_error_status(pdev);
+		pci_aer_clear_nonfatal_status(pdev);
 		pci_aer_clear_fatal_status(pdev);
 	}
 }

drivers/pci/pcie/err.c

@@ -197,7 +197,7 @@ void pcie_do_recovery(struct pci_dev *dev,
 	pci_walk_bus(bus, report_resume, &status);
 
 	pci_aer_clear_device_status(dev);
-	pci_cleanup_aer_uncorrect_error_status(dev);
+	pci_aer_clear_nonfatal_status(dev);
 	pci_info(dev, "AER: Device recovery successful\n");
 	return;
 

drivers/scsi/lpfc/lpfc_attr.c

@@ -5028,7 +5028,7 @@ static DEVICE_ATTR(lpfc_aer_support, S_IRUGO | S_IWUSR,
  * Description:
  * If the @buf contains 1 and the device currently has the AER support
  * enabled, then invokes the kernel AER helper routine
- * pci_aer_clear_nonfatal_status to clean up the uncorrectable error
+ * pci_aer_clear_nonfatal_status() to clean up the uncorrectable
  * status register.
  *
  * Notes:
@@ -5054,11 +5054,7 @@ lpfc_aer_cleanup_state(struct device *dev, struct device_attribute *attr,
 		return -EINVAL;
 
 	if (phba->hba_flag & HBA_AER_ENABLED)
-#if defined(BUILD_SLES15SP2) || defined(BUILD_RHEL83)
 		rc = pci_aer_clear_nonfatal_status(phba->pcidev);
-#else
-		rc = pci_cleanup_aer_uncorrect_error_status(phba->pcidev);
-#endif
 
 	if (rc == 0)
 		return strlen(buf);

include/linux/aer.h

@@ -44,8 +44,7 @@ struct aer_capability_regs {
 /* PCIe port driver needs this function to enable AER */
 int pci_enable_pcie_error_reporting(struct pci_dev *dev);
 int pci_disable_pcie_error_reporting(struct pci_dev *dev);
-int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev);
-int pci_cleanup_aer_error_status_regs(struct pci_dev *dev);
+int pci_aer_clear_nonfatal_status(struct pci_dev *dev);
 void pci_save_aer_state(struct pci_dev *dev);
 void pci_restore_aer_state(struct pci_dev *dev);
 #else
@@ -57,11 +56,7 @@ static inline int pci_disable_pcie_error_reporting(struct pci_dev *dev)
 {
 	return -EINVAL;
 }
-static inline int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev)
-{
-	return -EINVAL;
-}
-static inline int pci_cleanup_aer_error_status_regs(struct pci_dev *dev)
+static inline int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
 {
 	return -EINVAL;
 }
@@ -74,5 +69,17 @@ void cper_print_aer(struct pci_dev *dev, int aer_severity,
 int cper_severity_to_aer(int cper_severity);
 void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn,
 		       int severity, struct aer_capability_regs *aer_regs);
+
+/*
+ * TK4: For compact reason, an alias for pci_cleanup_aer_uncorrect_error_status
+ * to pci_aer_clear_nonfatal_status is added here. Since many modules really
+ * expects an 5.4 kernel to have pci_cleanup_aer_uncorrect_error_status, this
+ * is useful as a compact layer.
+ */
+static inline int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev)
+{
+       return pci_aer_clear_nonfatal_status(dev);
+}
+
 #endif //_AER_H_