Commit 4aa9bc95 authored by Michael Ellerman's avatar Michael Ellerman Committed by Greg Kroah-Hartman
Browse files

MSI: Use a list instead of the custom link structure 



The msi descriptors are linked together with what looks a lot like
a linked list, but isn't a struct list_head list. Make it one.

The only complication is that previously we walked a list of irqs, and
got the descriptor for each with get_irq_msi(). Now we have a list of
descriptors and need to get the irq out of it, so it needs to be in the
actual struct msi_desc. We use 0 to indicate no irq is setup.

Signed-off-by: default avatarMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent bab41e9b

drivers/pci/msi.c

+24 −42
Original line number Diff line number Diff line
@@ -218,7 +218,8 @@ static struct msi_desc* alloc_msi_entry(void) 
	if (!entry)

		return NULL;



	entry->link.tail = entry->link.head = 0;	/* single message */

	INIT_LIST_HEAD(&entry->list);

	entry->irq = 0;

	entry->dev = NULL;



	return entry;
@@ -253,7 +254,6 @@ static void __pci_restore_msi_state(struct pci_dev *dev) 
static void __pci_restore_msix_state(struct pci_dev *dev)

{

	int pos;

	int irq, head, tail = 0;

	struct msi_desc *entry;

	u16 control;
@@ -263,18 +263,14 @@ static void __pci_restore_msix_state(struct pci_dev *dev) 
	/* route the table */

	pci_intx(dev, 0);		/* disable intx */

	msix_set_enable(dev, 0);

	irq = head = dev->first_msi_irq;

	entry = get_irq_msi(irq);

	pos = entry->msi_attrib.pos;

	while (head != tail) {

		entry = get_irq_msi(irq);

		write_msi_msg(irq, &entry->msg);

		msi_set_mask_bit(irq, entry->msi_attrib.masked);



		tail = entry->link.tail;

		irq = tail;

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

		write_msi_msg(entry->irq, &entry->msg);

		msi_set_mask_bit(entry->irq, entry->msi_attrib.masked);

	}



	entry = get_irq_msi(dev->first_msi_irq);

	pos = entry->msi_attrib.pos;

	pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);

	control &= ~PCI_MSIX_FLAGS_MASKALL;

	control |= PCI_MSIX_FLAGS_ENABLE;
@@ -343,8 +339,8 @@ static int msi_capability_init(struct pci_dev *dev) 
		kfree(entry);

		return irq;

	}

	entry->link.head = irq;

	entry->link.tail = irq;

	entry->irq = irq;

	list_add(&entry->list, &dev->msi_list);

	dev->first_msi_irq = irq;

	set_irq_msi(irq, entry);
@@ -370,8 +366,8 @@ static int msi_capability_init(struct pci_dev *dev) 
static int msix_capability_init(struct pci_dev *dev,

				struct msix_entry *entries, int nvec)

{

	struct msi_desc *head = NULL, *tail = NULL, *entry = NULL;

	int irq, pos, i, j, nr_entries, temp = 0;

	struct msi_desc *entry;

	int irq, pos, i, j, nr_entries;

	unsigned long phys_addr;

	u32 table_offset;

 	u16 control;
@@ -416,19 +412,9 @@ static int msix_capability_init(struct pci_dev *dev, 
			kfree(entry);

			break;

		}

		entry->irq = irq;

 		entries[i].vector = irq;

		if (!head) {

			entry->link.head = irq;

			entry->link.tail = irq;

			head = entry;

		} else {

			entry->link.head = temp;

			entry->link.tail = tail->link.tail;

			tail->link.tail = irq;

			head->link.head = irq;

		}

		temp = irq;

		tail = entry;

		list_add(&entry->list, &dev->msi_list);



		set_irq_msi(irq, entry);

	}
@@ -557,7 +543,7 @@ EXPORT_SYMBOL(pci_disable_msi); 
static int msi_free_irq(struct pci_dev* dev, int irq)

{

	struct msi_desc *entry;

	int head, entry_nr, type;

	int entry_nr, type;

	void __iomem *base;



	BUG_ON(irq_has_action(irq));
@@ -568,10 +554,8 @@ static int msi_free_irq(struct pci_dev* dev, int irq) 
	}

	type = entry->msi_attrib.type;

	entry_nr = entry->msi_attrib.entry_nr;

	head = entry->link.head;

	base = entry->mask_base;

	get_irq_msi(entry->link.head)->link.tail = entry->link.tail;

	get_irq_msi(entry->link.tail)->link.head = entry->link.head;

	list_del(&entry->list);



	arch_teardown_msi_irq(irq);

	kfree(entry);
@@ -580,7 +564,7 @@ static int msi_free_irq(struct pci_dev* dev, int irq) 
		writel(1, base + entry_nr * PCI_MSIX_ENTRY_SIZE +

			PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);



		if (head == irq)

		if (list_empty(&dev->msi_list))

			iounmap(base);

	}
@@ -646,17 +630,10 @@ EXPORT_SYMBOL(pci_enable_msix); 


static void msix_free_all_irqs(struct pci_dev *dev)

{

	int irq, head, tail = 0;



	irq = head = dev->first_msi_irq;

	while (head != tail) {

		tail = get_irq_msi(irq)->link.tail;

	struct msi_desc *entry;



		if (irq != head)

			msi_free_irq(dev, irq);

		irq = tail;

	}

	msi_free_irq(dev, irq);

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

		msi_free_irq(dev, entry->irq);

	dev->first_msi_irq = 0;

}
@@ -699,6 +676,11 @@ void pci_no_msi(void) 
	pci_msi_enable = 0;

}



void pci_msi_init_pci_dev(struct pci_dev *dev)

{

	INIT_LIST_HEAD(&dev->msi_list);

}





/* Arch hooks */

drivers/pci/pci.h

+2 −0
Original line number Diff line number Diff line
@@ -47,8 +47,10 @@ extern unsigned int pci_pm_d3_delay; 


#ifdef CONFIG_PCI_MSI

void pci_no_msi(void);

extern void pci_msi_init_pci_dev(struct pci_dev *dev);

#else

static inline void pci_no_msi(void) { }

static inline void pci_msi_init_pci_dev(struct pci_dev *dev) { }

#endif



#if defined(CONFIG_PCI_MSI) && defined(CONFIG_PM)

drivers/pci/probe.c

+2 −0
Original line number Diff line number Diff line
@@ -857,6 +857,8 @@ struct pci_dev *alloc_pci_dev(void) 
	INIT_LIST_HEAD(&dev->global_list);

	INIT_LIST_HEAD(&dev->bus_list);



	pci_msi_init_pci_dev(dev);



	return dev;

}

EXPORT_SYMBOL(alloc_pci_dev);

include/linux/msi.h

+4 −4
Original line number Diff line number Diff line 
#ifndef LINUX_MSI_H

#define LINUX_MSI_H



#include <linux/list.h>



struct msi_msg {

	u32	address_lo;	/* low 32 bits of msi message address */

	u32	address_hi;	/* high 32 bits of msi message address */
@@ -24,10 +26,8 @@ struct msi_desc { 
		unsigned default_irq;	/* default pre-assigned irq	  */

	}msi_attrib;



	struct {

		__u16	head;

		__u16	tail;

	}link;

	unsigned int irq;

	struct list_head list;



	void __iomem *mask_base;

	struct pci_dev *dev;

include/linux/pci.h

+1 −0
Original line number Diff line number Diff line
@@ -190,6 +190,7 @@ struct pci_dev { 
	struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */

#ifdef CONFIG_PCI_MSI

	unsigned int first_msi_irq;

	struct list_head msi_list;

#endif

};

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