[PATCH V4 09/11] powerpc/eeh: handle VF PE properly

[Wei Yang <weiyang@linux.vnet.ibm.com>]

Compared with Bus PE, VF PE just has one single pci function. This
introduces the difference of error handling on a VF PE.

For example in the hotplug case, EEH needs to remove and re-create the VF
properly. In the case when PF's error_detected() disable SRIOV, this patch
introduces a flag to mark the eeh_dev of a VF to avoid the slot_reset() and
resume(). Since the FW is not ware of the VF, this patch handles the VF
restore/reset in kernel directly.

This patch is to handle the VF PE properly in these cases.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/eeh.h   |    1 +
 arch/powerpc/kernel/eeh.c        |    1 +
 arch/powerpc/kernel/eeh_driver.c |  103 ++++++++++++++++++++++++++++++--------
 arch/powerpc/kernel/eeh_pe.c     |    3 +-
 4 files changed, 85 insertions(+), 23 deletions(-)

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index 3d64cf3..d24382c 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -140,6 +140,7 @@ struct eeh_dev {
 	struct pci_controller *phb;	/* Associated PHB		*/
 	struct pci_dn *pdn;		/* Associated PCI device node	*/
 	struct pci_dev *pdev;		/* Associated PCI device	*/
+	int    in_error;		/* Error flag for eeh_dev	*/
 	struct pci_dev *physfn;		/* Associated PF PORT		*/
 	struct pci_bus *bus;		/* PCI bus for partial hotplug	*/
 };
diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
index 221e280..077c3d1 100644
--- a/arch/powerpc/kernel/eeh.c
+++ b/arch/powerpc/kernel/eeh.c
@@ -1226,6 +1226,7 @@ void eeh_remove_device(struct pci_dev *dev)
 	 * from the parent PE during the BAR resotre.
 	 */
 	edev->pdev = NULL;
+	edev->in_error = 0;
 	dev->dev.archdata.edev = NULL;
 	if (!(edev->pe->state & EEH_PE_KEEP))
 		eeh_rmv_from_parent_pe(edev);
diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c
index 89eb4bc..292089e 100644
--- a/arch/powerpc/kernel/eeh_driver.c
+++ b/arch/powerpc/kernel/eeh_driver.c
@@ -211,6 +211,7 @@ static void *eeh_report_error(void *data, void *userdata)
 	if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
 	if (*res == PCI_ERS_RESULT_NONE) *res = rc;
 
+	edev->in_error = 1;
 	eeh_pcid_put(dev);
 	return NULL;
 }
@@ -282,7 +283,8 @@ static void *eeh_report_reset(void *data, void *userdata)
 
 	if (!driver->err_handler ||
 	    !driver->err_handler->slot_reset ||
-	    (edev->mode & EEH_DEV_NO_HANDLER)) {
+	    (edev->mode & EEH_DEV_NO_HANDLER) ||
+	    (!edev->in_error)) {
 		eeh_pcid_put(dev);
 		return NULL;
 	}
@@ -339,14 +341,16 @@ static void *eeh_report_resume(void *data, void *userdata)
 
 	if (!driver->err_handler ||
 	    !driver->err_handler->resume ||
-	    (edev->mode & EEH_DEV_NO_HANDLER)) {
+	    (edev->mode & EEH_DEV_NO_HANDLER) ||
+	    (!edev->in_error)) {
 		edev->mode &= ~EEH_DEV_NO_HANDLER;
-		eeh_pcid_put(dev);
-		return NULL;
+		goto out;
 	}
 
 	driver->err_handler->resume(dev);
 
+out:
+	edev->in_error = 0;
 	eeh_pcid_put(dev);
 	return NULL;
 }
@@ -386,12 +390,40 @@ static void *eeh_report_failure(void *data, void *userdata)
 	return NULL;
 }
 
+#ifdef CONFIG_PCI_IOV
+static void *eeh_add_virt_device(void *data, void *userdata)
+{
+	struct pci_driver *driver;
+	struct eeh_dev *edev = (struct eeh_dev *)data;
+	struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
+	struct pci_dn *pdn = eeh_dev_to_pdn(edev);
+
+	if (!(edev->physfn)) {
+		pr_warn("%s: EEH dev %04x:%02x:%02x:%01x not for VF\n",
+			__func__, edev->phb->global_number, pdn->busno,
+			PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));
+		return NULL;
+	}
+
+	driver = eeh_pcid_get(dev);
+	if (driver) {
+		eeh_pcid_put(dev);
+		if (driver->err_handler)
+			return NULL;
+	}
+
+	pci_iov_virtfn_add(edev->physfn, pdn->vf_index, 0);
+	return NULL;
+}
+#endif /* CONFIG_PCI_IOV */
+
 static void *eeh_rmv_device(void *data, void *userdata)
 {
 	struct pci_driver *driver;
 	struct eeh_dev *edev = (struct eeh_dev *)data;
 	struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
 	int *removed = (int *)userdata;
+	struct pci_dn *pdn = eeh_dev_to_pdn(edev);
 
 	/*
 	 * Actually, we should remove the PCI bridges as well.
@@ -416,7 +448,7 @@ static void *eeh_rmv_device(void *data, void *userdata)
 	driver = eeh_pcid_get(dev);
 	if (driver) {
 		eeh_pcid_put(dev);
-		if (driver->err_handler)
+		if (removed && driver->err_handler)
 			return NULL;
 	}
 
@@ -425,11 +457,18 @@ static void *eeh_rmv_device(void *data, void *userdata)
 		 pci_name(dev));
 	edev->bus = dev->bus;
 	edev->mode |= EEH_DEV_DISCONNECTED;
-	(*removed)++;
-
-	pci_lock_rescan_remove();
-	pci_stop_and_remove_bus_device(dev);
-	pci_unlock_rescan_remove();
+	if (removed)
+		(*removed)++;
+
+	if (edev->physfn) {
+		pci_iov_virtfn_remove(edev->physfn, pdn->vf_index, 0);
+		edev->pdev = NULL;
+		pdn->pe_number = IODA_INVALID_PE;
+	} else {
+		pci_lock_rescan_remove();
+		pci_stop_and_remove_bus_device(dev);
+		pci_unlock_rescan_remove();
+	}
 
 	return NULL;
 }
@@ -548,6 +587,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus)
 	struct pci_bus *frozen_bus = eeh_pe_bus_get(pe);
 	struct timeval tstamp;
 	int cnt, rc, removed = 0;
+	struct eeh_dev *edev;
 
 	/* pcibios will clear the counter; save the value */
 	cnt = pe->freeze_count;
@@ -561,12 +601,15 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus)
 	 */
 	eeh_pe_state_mark(pe, EEH_PE_KEEP);
 	if (bus) {
-		pci_lock_rescan_remove();
-		pcibios_remove_pci_devices(bus);
-		pci_unlock_rescan_remove();
-	} else if (frozen_bus) {
+		if (pe->type & EEH_PE_VF)
+			eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
+		else {
+			pci_lock_rescan_remove();
+			pcibios_remove_pci_devices(bus);
+			pci_unlock_rescan_remove();
+		}
+	} else if (frozen_bus)
 		eeh_pe_dev_traverse(pe, eeh_rmv_device, &removed);
-	}
 
 	/*
 	 * Reset the pci controller. (Asserts RST#; resets config space).
@@ -607,14 +650,26 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus)
 		 * PE. We should disconnect it so the binding can be
 		 * rebuilt when adding PCI devices.
 		 */
+		edev = list_first_entry(&pe->edevs, struct eeh_dev, list);
 		eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL);
-		pcibios_add_pci_devices(bus);
+#ifdef CONFIG_PCI_IOV
+		if (pe->type & EEH_PE_VF)
+			eeh_add_virt_device(edev, NULL);
+		else
+#endif
+			pcibios_add_pci_devices(bus);
 	} else if (frozen_bus && removed) {
 		pr_info("EEH: Sleep 5s ahead of partial hotplug\n");
 		ssleep(5);
 
+		edev = list_first_entry(&pe->edevs, struct eeh_dev, list);
 		eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL);
-		pcibios_add_pci_devices(frozen_bus);
+#ifdef CONFIG_PCI_IOV
+		if (pe->type & EEH_PE_VF)
+			eeh_add_virt_device(edev, NULL);
+		else
+#endif
+			pcibios_add_pci_devices(frozen_bus);
 	}
 	eeh_pe_state_clear(pe, EEH_PE_KEEP);
 
@@ -792,11 +847,15 @@ perm_error:
 	 * the their PCI config any more.
 	 */
 	if (frozen_bus) {
-		eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
-
-		pci_lock_rescan_remove();
-		pcibios_remove_pci_devices(frozen_bus);
-		pci_unlock_rescan_remove();
+		if (pe->type & EEH_PE_VF) {
+			eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
+			eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
+		} else {
+			eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
+			pci_lock_rescan_remove();
+			pcibios_remove_pci_devices(frozen_bus);
+			pci_unlock_rescan_remove();
+		}
 	}
 }
 
diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index 260a701..5cde950 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c
@@ -914,7 +914,8 @@ struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
 	if (pe->type & EEH_PE_PHB) {
 		bus = pe->phb->bus;
 	} else if (pe->type & EEH_PE_BUS ||
-		   pe->type & EEH_PE_DEVICE) {
+		   pe->type & EEH_PE_DEVICE ||
+		   pe->type & EEH_PE_VF) {
 		if (pe->bus) {
 			bus = pe->bus;
 			goto out;
-- 
1.7.9.5