pci/irq: let pci_device_shutdown to call pci_msi_shutdown v2

[PATCH 2/2] pci/irq: let pci_device_shutdown to call pci_msi_shutdown v2

this change

| commit 23a274c
| Author: Prakash, Sathya <sathya.prakash@lsi.com>
| Date:   Fri Mar 7 15:53:21 2008 +0530
|
|     [SCSI] mpt fusion: Enable MSI by default for SAS controllers
|
|     This patch modifies the driver to enable MSI by default for all SAS chips.
|
|     Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
|     Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
|
Causes the kexec of a RHEL 5.1 kernel to fail.

root casue: the rhel 5.1 kernel still uses INTx emulation.  and
mptscsih_shutdown doesn't call pci_disable_msi to reenable INTx on kexec path

So call pci_msi_shutdown in the shutdown path to do the same thing to msix

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>

drivers/pci/msi.c

@@ -571,10 +571,9 @@ int pci_enable_msi(struct pci_dev* dev)
 }
 EXPORT_SYMBOL(pci_enable_msi);
 
-void pci_disable_msi(struct pci_dev* dev)
+void pci_msi_shutdown(struct pci_dev* dev)
 {
 	struct msi_desc *entry;
-	int default_irq;
 
 	if (!pci_msi_enable || !dev || !dev->msi_enabled)
 		return;
@@ -590,15 +589,26 @@ void pci_disable_msi(struct pci_dev* dev)
 		u32 mask = entry->msi_attrib.maskbits_mask;
 		msi_set_mask_bits(dev->irq, mask, ~mask);
 	}
-	if (!entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
+	if (!entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI)
 		return;
-	}
-
-	default_irq = entry->msi_attrib.default_irq;
-	msi_free_irqs(dev);
 
 	/* Restore dev->irq to its default pin-assertion irq */
-	dev->irq = default_irq;
+	dev->irq = entry->msi_attrib.default_irq;
+}
+void pci_disable_msi(struct pci_dev* dev)
+{
+	struct msi_desc *entry;
+
+	if (!pci_msi_enable || !dev || !dev->msi_enabled)
+		return;
+
+	pci_msi_shutdown(dev);
+
+	entry = list_entry(dev->msi_list.next, struct msi_desc, list);
+	if (!entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI)
+		return;
+
+	msi_free_irqs(dev);
 }
 EXPORT_SYMBOL(pci_disable_msi);
 
@@ -691,14 +701,21 @@ static void msix_free_all_irqs(struct pci_dev *dev)
 	msi_free_irqs(dev);
 }
 
-void pci_disable_msix(struct pci_dev* dev)
+void pci_msix_shutdown(struct pci_dev* dev)
 {
 	if (!pci_msi_enable || !dev || !dev->msix_enabled)
 		return;
 
 	msix_set_enable(dev, 0);
 	pci_intx_for_msi(dev, 1);
 	dev->msix_enabled = 0;
+}
+void pci_disable_msix(struct pci_dev* dev)
+{
+	if (!pci_msi_enable || !dev || !dev->msix_enabled)
+		return;
+
+	pci_msix_shutdown(dev);
 
 	msix_free_all_irqs(dev);
 }

drivers/pci/pci-driver.c

@@ -360,6 +360,8 @@ static void pci_device_shutdown(struct device *dev)
 
 	if (drv && drv->shutdown)
 		drv->shutdown(pci_dev);
+	pci_msi_shutdown(pci_dev);
+	pci_msix_shutdown(pci_dev);
 }
 
 /**

include/linux/pci.h

@@ -701,6 +701,8 @@ static inline int pci_enable_msi(struct pci_dev *dev)
 	return -1;
 }
 
+static inline void pci_msi_shutdown(struct pci_dev *dev)
+{ }
 static inline void pci_disable_msi(struct pci_dev *dev)
 { }
 
@@ -710,6 +712,8 @@ static inline int pci_enable_msix(struct pci_dev *dev,
 	return -1;
 }
 
+static inline void pci_msix_shutdown(struct pci_dev *dev)
+{ }
 static inline void pci_disable_msix(struct pci_dev *dev)
 { }
 
@@ -720,9 +724,11 @@ static inline void pci_restore_msi_state(struct pci_dev *dev)
 { }
 #else
 extern int pci_enable_msi(struct pci_dev *dev);
+extern void pci_msi_shutdown(struct pci_dev *dev);
 extern void pci_disable_msi(struct pci_dev *dev);
 extern int pci_enable_msix(struct pci_dev *dev,
 	struct msix_entry *entries, int nvec);
+extern void pci_msix_shutdown(struct pci_dev *dev);
 extern void pci_disable_msix(struct pci_dev *dev);
 extern void msi_remove_pci_irq_vectors(struct pci_dev *dev);
 extern void pci_restore_msi_state(struct pci_dev *dev);