Commit 032de8e2 authored by Michael Ellerman's avatar Michael Ellerman Committed by Greg Kroah-Hartman
Browse files

MSI: Give archs the option to free all MSI/Xs at once. 



This patch introduces an optional function, arch_teardown_msi_irqs(),
which gives an arch the opportunity to do per-device teardown for
MSI/X. If that's not required, the default version simply calls
arch_teardown_msi_irq() for each msi irq required.

arch_teardown_msi_irqs() is simply passed a pdev, attached to the pdev
is a list of msi_descs, it is up to the arch to free the irq associated
with each of these as appropriate.

For archs that _don't_ implement arch_teardown_msi_irqs(), all msi_descs
with irq == 0 are considered unallocated, and the arch teardown routine
is not called on them.

Signed-off-by: default avatarMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 9c831334

drivers/pci/msi.c

+39 −36
Original line number Diff line number Diff line
@@ -207,7 +207,7 @@ void unmask_msi_irq(unsigned int irq) 
	msix_flush_writes(irq);

}



static int msi_free_irq(struct pci_dev* dev, int irq);

static int msi_free_irqs(struct pci_dev* dev);





static struct msi_desc* alloc_msi_entry(void)
@@ -339,8 +339,7 @@ static int msi_capability_init(struct pci_dev *dev) 
	/* Configure MSI capability structure */

	ret = arch_setup_msi_irqs(dev, 1, PCI_CAP_ID_MSI);

	if (ret) {

		list_del(&entry->list);

		kfree(entry);

		msi_free_irqs(dev);

		return ret;

	}
@@ -415,10 +414,11 @@ static int msix_capability_init(struct pci_dev *dev, 
		list_for_each_entry(entry, &dev->msi_list, list) {

			if (entry->irq != 0) {

				avail++;

				msi_free_irq(dev, entry->irq);

			}

		}



		msi_free_irqs(dev);



		/* If we had some success report the number of irqs

		 * we succeeded in setting up.

		 */
@@ -539,39 +539,33 @@ void pci_disable_msi(struct pci_dev* dev) 
	}



	default_irq = entry->msi_attrib.default_irq;

	msi_free_irq(dev, entry->irq);

	msi_free_irqs(dev);



	/* Restore dev->irq to its default pin-assertion irq */

	dev->irq = default_irq;

}

EXPORT_SYMBOL(pci_disable_msi);



static int msi_free_irq(struct pci_dev* dev, int irq)

static int msi_free_irqs(struct pci_dev* dev)

{

	struct msi_desc *entry;

	int entry_nr, type;

	void __iomem *base;

	struct msi_desc *entry, *tmp;



	BUG_ON(irq_has_action(irq));

	list_for_each_entry(entry, &dev->msi_list, list)

		BUG_ON(irq_has_action(entry->irq));



	entry = get_irq_msi(irq);

	if (!entry || entry->dev != dev) {

		return -EINVAL;

	arch_teardown_msi_irqs(dev);



	list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {

		if (entry->msi_attrib.type == PCI_CAP_ID_MSIX) {

			if (list_is_last(&entry->list, &dev->msi_list))

				iounmap(entry->mask_base);



			writel(1, entry->mask_base + entry->msi_attrib.entry_nr

				  * PCI_MSIX_ENTRY_SIZE

				  + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);

		}

	type = entry->msi_attrib.type;

	entry_nr = entry->msi_attrib.entry_nr;

	base = entry->mask_base;

		list_del(&entry->list);



	arch_teardown_msi_irq(irq);

		kfree(entry);



	if (type == PCI_CAP_ID_MSIX) {

		writel(1, base + entry_nr * PCI_MSIX_ENTRY_SIZE +

			PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);



		if (list_empty(&dev->msi_list))

			iounmap(base);

	}



	return 0;
@@ -636,10 +630,7 @@ EXPORT_SYMBOL(pci_enable_msix); 


static void msix_free_all_irqs(struct pci_dev *dev)

{

	struct msi_desc *entry;



	list_for_each_entry(entry, &dev->msi_list, list)

		msi_free_irq(dev, entry->irq);

	msi_free_irqs(dev);

}



void pci_disable_msix(struct pci_dev* dev)
@@ -669,12 +660,8 @@ void msi_remove_pci_irq_vectors(struct pci_dev* dev) 
	if (!pci_msi_enable || !dev)

 		return;



	if (dev->msi_enabled) {

		struct msi_desc *entry;

		BUG_ON(list_empty(&dev->msi_list));

		entry = list_entry(dev->msi_list.next, struct msi_desc, list);

		msi_free_irq(dev, entry->irq);

	}

	if (dev->msi_enabled)

		msi_free_irqs(dev);



	if (dev->msix_enabled)

		msix_free_all_irqs(dev);
@@ -719,3 +706,19 @@ arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) 


	return 0;

}



void __attribute__ ((weak)) arch_teardown_msi_irq(unsigned int irq)

{

	return;

}



void __attribute__ ((weak))

arch_teardown_msi_irqs(struct pci_dev *dev)

{

	struct msi_desc *entry;



	list_for_each_entry(entry, &dev->msi_list, list) {

		if (entry->irq != 0)

			arch_teardown_msi_irq(entry->irq);

	}

}

include/linux/msi.h

+1 −0
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ struct msi_desc { 
int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc);

void arch_teardown_msi_irq(unsigned int irq);

extern int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);

extern void arch_teardown_msi_irqs(struct pci_dev *dev);

extern int arch_msi_check_device(struct pci_dev* dev, int nvec, int type);

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