1 files changed, 655 insertions, 284 deletions

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index d9f06fbfa0b..13f3d303727 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -10,32 +10,63 @@
 #include <linux/mm.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
-#include <linux/init.h>
+#include <linux/export.h>
 #include <linux/ioport.h>
 #include <linux/pci.h>
 #include <linux/proc_fs.h>
 #include <linux/msi.h>
 #include <linux/smp.h>
-
-#include <asm/errno.h>
-#include <asm/io.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/slab.h>
 
 #include "pci.h"
-#include "msi.h"
 
 static int pci_msi_enable = 1;
 
+#define msix_table_size(flags)	((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
+
+
 /* Arch hooks */
 
-#ifndef arch_msi_check_device
-int arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
+int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
 {
+	struct msi_chip *chip = dev->bus->msi;
+	int err;
+
+	if (!chip || !chip->setup_irq)
+		return -EINVAL;
+
+	err = chip->setup_irq(chip, dev, desc);
+	if (err < 0)
+		return err;
+
+	irq_set_chip_data(desc->irq, chip);
+
 	return 0;
 }
-#endif
 
-#ifndef arch_setup_msi_irqs
-int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+void __weak arch_teardown_msi_irq(unsigned int irq)
+{
+	struct msi_chip *chip = irq_get_chip_data(irq);
+
+	if (!chip || !chip->teardown_irq)
+		return;
+
+	chip->teardown_irq(chip, irq);
+}
+
+int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
+{
+	struct msi_chip *chip = dev->bus->msi;
+
+	if (!chip || !chip->check_device)
+		return 0;
+
+	return chip->check_device(chip, dev, nvec, type);
+}
+
+int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
 	struct msi_desc *entry;
 	int ret;
@@ -57,10 +88,12 @@ int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 
 	return 0;
 }
-#endif
 
-#ifndef arch_teardown_msi_irqs
-void arch_teardown_msi_irqs(struct pci_dev *dev)
+/*
+ * We have a default implementation available as a separate non-weak
+ * function, as it is used by the Xen x86 PCI code
+ */
+void default_teardown_msi_irqs(struct pci_dev *dev)
 {
 	struct msi_desc *entry;
 
@@ -68,39 +101,63 @@ void arch_teardown_msi_irqs(struct pci_dev *dev)
 		int i, nvec;
 		if (entry->irq == 0)
 			continue;
-		nvec = 1 << entry->msi_attrib.multiple;
+		if (entry->nvec_used)
+			nvec = entry->nvec_used;
+		else
+			nvec = 1 << entry->msi_attrib.multiple;
 		for (i = 0; i < nvec; i++)
 			arch_teardown_msi_irq(entry->irq + i);
 	}
 }
-#endif
 
-static void msi_set_enable(struct pci_dev *dev, int pos, int enable)
+void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
 {
-	u16 control;
+	return default_teardown_msi_irqs(dev);
+}
+
+static void default_restore_msi_irq(struct pci_dev *dev, int irq)
+{
+	struct msi_desc *entry;
+
+	entry = NULL;
+	if (dev->msix_enabled) {
+		list_for_each_entry(entry, &dev->msi_list, list) {
+			if (irq == entry->irq)
+				break;
+		}
+	} else if (dev->msi_enabled)  {
+		entry = irq_get_msi_desc(irq);
+	}
+
+	if (entry)
+		write_msi_msg(irq, &entry->msg);
+}
+
+void __weak arch_restore_msi_irqs(struct pci_dev *dev)
+{
+	return default_restore_msi_irqs(dev);
+}
 
-	BUG_ON(!pos);
+static void msi_set_enable(struct pci_dev *dev, int enable)
+{
+	u16 control;
 
-	pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
+	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
 	control &= ~PCI_MSI_FLAGS_ENABLE;
 	if (enable)
 		control |= PCI_MSI_FLAGS_ENABLE;
-	pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
+	pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
 }
 
 static void msix_set_enable(struct pci_dev *dev, int enable)
 {
-	int pos;
 	u16 control;
 
-	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
-	if (pos) {
-		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
-		control &= ~PCI_MSIX_FLAGS_ENABLE;
-		if (enable)
-			control |= PCI_MSIX_FLAGS_ENABLE;
-		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
-	}
+	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
+	control &= ~PCI_MSIX_FLAGS_ENABLE;
+	if (enable)
+		control |= PCI_MSIX_FLAGS_ENABLE;
+	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);
 }
 
 static inline __attribute_const__ u32 msi_mask(unsigned x)
@@ -127,17 +184,28 @@ static inline __attribute_const__ u32 msi_enabled_mask(u16 control)
  * reliably as devices without an INTx disable bit will then generate a
  * level IRQ which will never be cleared.
  */
-static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
+u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 {
 	u32 mask_bits = desc->masked;
 
 	if (!desc->msi_attrib.maskbit)
-		return;
+		return 0;
 
 	mask_bits &= ~mask;
 	mask_bits |= flag;
 	pci_write_config_dword(desc->dev, desc->mask_pos, mask_bits);
-	desc->masked = mask_bits;
+
+	return mask_bits;
+}
+
+__weak u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
+{
+	return default_msi_mask_irq(desc, mask, flag);
+}
+
+static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
+{
+	desc->masked = arch_msi_mask_irq(desc, mask, flag);
 }
 
 /*
@@ -147,64 +215,86 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
  * file.  This saves a few milliseconds when initialising devices with lots
  * of MSI-X interrupts.
  */
-static void msix_mask_irq(struct msi_desc *desc, u32 flag)
+u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag)
 {
 	u32 mask_bits = desc->masked;
 	unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
-					PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
-	mask_bits &= ~1;
-	mask_bits |= flag;
+						PCI_MSIX_ENTRY_VECTOR_CTRL;
+	mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
+	if (flag)
+		mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
 	writel(mask_bits, desc->mask_base + offset);
-	desc->masked = mask_bits;
+
+	return mask_bits;
+}
+
+__weak u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag)
+{
+	return default_msix_mask_irq(desc, flag);
+}
+
+static void msix_mask_irq(struct msi_desc *desc, u32 flag)
+{
+	desc->masked = arch_msix_mask_irq(desc, flag);
 }
 
-static void msi_set_mask_bit(unsigned irq, u32 flag)
+static void msi_set_mask_bit(struct irq_data *data, u32 flag)
 {
-	struct msi_desc *desc = get_irq_msi(irq);
+	struct msi_desc *desc = irq_data_get_msi(data);
 
 	if (desc->msi_attrib.is_msix) {
 		msix_mask_irq(desc, flag);
 		readl(desc->mask_base);		/* Flush write to device */
 	} else {
-		unsigned offset = irq - desc->dev->irq;
+		unsigned offset = data->irq - desc->dev->irq;
 		msi_mask_irq(desc, 1 << offset, flag << offset);
 	}
 }
 
-void mask_msi_irq(unsigned int irq)
+void mask_msi_irq(struct irq_data *data)
+{
+	msi_set_mask_bit(data, 1);
+}
+
+void unmask_msi_irq(struct irq_data *data)
 {
-	msi_set_mask_bit(irq, 1);
+	msi_set_mask_bit(data, 0);
 }
 
-void unmask_msi_irq(unsigned int irq)
+void default_restore_msi_irqs(struct pci_dev *dev)
 {
-	msi_set_mask_bit(irq, 0);
+	struct msi_desc *entry;
+
+	list_for_each_entry(entry, &dev->msi_list, list) {
+		default_restore_msi_irq(dev, entry->irq);
+	}
 }
 
-void read_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg)
+void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
-	struct msi_desc *entry = get_irq_desc_msi(desc);
+	BUG_ON(entry->dev->current_state != PCI_D0);
+
 	if (entry->msi_attrib.is_msix) {
 		void __iomem *base = entry->mask_base +
 			entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
 
-		msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
-		msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
-		msg->data = readl(base + PCI_MSIX_ENTRY_DATA_OFFSET);
+		msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR);
+		msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR);
+		msg->data = readl(base + PCI_MSIX_ENTRY_DATA);
 	} else {
 		struct pci_dev *dev = entry->dev;
-		int pos = entry->msi_attrib.pos;
+		int pos = dev->msi_cap;
 		u16 data;
 
-		pci_read_config_dword(dev, msi_lower_address_reg(pos),
-					&msg->address_lo);
+		pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
+				      &msg->address_lo);
 		if (entry->msi_attrib.is_64) {
-			pci_read_config_dword(dev, msi_upper_address_reg(pos),
-						&msg->address_hi);
-			pci_read_config_word(dev, msi_data_reg(pos, 1), &data);
+			pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
+					      &msg->address_hi);
+			pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data);
 		} else {
 			msg->address_hi = 0;
-			pci_read_config_word(dev, msi_data_reg(pos, 0), &data);
+			pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data);
 		}
 		msg->data = data;
 	}
@@ -212,44 +302,60 @@ void read_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg)
 
 void read_msi_msg(unsigned int irq, struct msi_msg *msg)
 {
-	struct irq_desc *desc = irq_to_desc(irq);
+	struct msi_desc *entry = irq_get_msi_desc(irq);
 
-	read_msi_msg_desc(desc, msg);
+	__read_msi_msg(entry, msg);
 }
 
-void write_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg)
+void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
-	struct msi_desc *entry = get_irq_desc_msi(desc);
-	if (entry->msi_attrib.is_msix) {
+	/* Assert that the cache is valid, assuming that
+	 * valid messages are not all-zeroes. */
+	BUG_ON(!(entry->msg.address_hi | entry->msg.address_lo |
+		 entry->msg.data));
+
+	*msg = entry->msg;
+}
+
+void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
+{
+	struct msi_desc *entry = irq_get_msi_desc(irq);
+
+	__get_cached_msi_msg(entry, msg);
+}
+
+void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
+{
+	if (entry->dev->current_state != PCI_D0) {
+		/* Don't touch the hardware now */
+	} else if (entry->msi_attrib.is_msix) {
 		void __iomem *base;
 		base = entry->mask_base +
 			entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
 
-		writel(msg->address_lo,
-			base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
-		writel(msg->address_hi,
-			base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
-		writel(msg->data, base + PCI_MSIX_ENTRY_DATA_OFFSET);
+		writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR);
+		writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR);
+		writel(msg->data, base + PCI_MSIX_ENTRY_DATA);
 	} else {
 		struct pci_dev *dev = entry->dev;
-		int pos = entry->msi_attrib.pos;
+		int pos = dev->msi_cap;
 		u16 msgctl;
 
-		pci_read_config_word(dev, msi_control_reg(pos), &msgctl);
+		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl);
 		msgctl &= ~PCI_MSI_FLAGS_QSIZE;
 		msgctl |= entry->msi_attrib.multiple << 4;
-		pci_write_config_word(dev, msi_control_reg(pos), msgctl);
+		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, msgctl);
 
-		pci_write_config_dword(dev, msi_lower_address_reg(pos),
-					msg->address_lo);
+		pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
+				       msg->address_lo);
 		if (entry->msi_attrib.is_64) {
-			pci_write_config_dword(dev, msi_upper_address_reg(pos),
-						msg->address_hi);
-			pci_write_config_word(dev, msi_data_reg(pos, 1),
-						msg->data);
+			pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
+					       msg->address_hi);
+			pci_write_config_word(dev, pos + PCI_MSI_DATA_64,
+					      msg->data);
 		} else {
-			pci_write_config_word(dev, msi_data_reg(pos, 0),
-						msg->data);
+			pci_write_config_word(dev, pos + PCI_MSI_DATA_32,
+					      msg->data);
 		}
 	}
 	entry->msg = *msg;
@@ -257,12 +363,69 @@ void write_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg)
 
 void write_msi_msg(unsigned int irq, struct msi_msg *msg)
 {
-	struct irq_desc *desc = irq_to_desc(irq);
+	struct msi_desc *entry = irq_get_msi_desc(irq);
 
-	write_msi_msg_desc(desc, msg);
+	__write_msi_msg(entry, msg);
 }
 
-static int msi_free_irqs(struct pci_dev* dev);
+static void free_msi_irqs(struct pci_dev *dev)
+{
+	struct msi_desc *entry, *tmp;
+	struct attribute **msi_attrs;
+	struct device_attribute *dev_attr;
+	int count = 0;
+
+	list_for_each_entry(entry, &dev->msi_list, list) {
+		int i, nvec;
+		if (!entry->irq)
+			continue;
+		if (entry->nvec_used)
+			nvec = entry->nvec_used;
+		else
+			nvec = 1 << entry->msi_attrib.multiple;
+		for (i = 0; i < nvec; i++)
+			BUG_ON(irq_has_action(entry->irq + i));
+	}
+
+	arch_teardown_msi_irqs(dev);
+
+	list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {
+		if (entry->msi_attrib.is_msix) {
+			if (list_is_last(&entry->list, &dev->msi_list))
+				iounmap(entry->mask_base);
+		}
+
+		/*
+		 * Its possible that we get into this path
+		 * When populate_msi_sysfs fails, which means the entries
+		 * were not registered with sysfs.  In that case don't
+		 * unregister them.
+		 */
+		if (entry->kobj.parent) {
+			kobject_del(&entry->kobj);
+			kobject_put(&entry->kobj);
+		}
+
+		list_del(&entry->list);
+		kfree(entry);
+	}
+
+	if (dev->msi_irq_groups) {
+		sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups);
+		msi_attrs = dev->msi_irq_groups[0]->attrs;
+		while (msi_attrs[count]) {
+			dev_attr = container_of(msi_attrs[count],
+						struct device_attribute, attr);
+			kfree(dev_attr->attr.name);
+			kfree(dev_attr);
+			++count;
+		}
+		kfree(msi_attrs);
+		kfree(dev->msi_irq_groups[0]);
+		kfree(dev->msi_irq_groups);
+		dev->msi_irq_groups = NULL;
+	}
+}
 
 static struct msi_desc *alloc_msi_entry(struct pci_dev *dev)
 {
@@ -284,52 +447,48 @@ static void pci_intx_for_msi(struct pci_dev *dev, int enable)
 
 static void __pci_restore_msi_state(struct pci_dev *dev)
 {
-	int pos;
 	u16 control;
 	struct msi_desc *entry;
 
 	if (!dev->msi_enabled)
 		return;
 
-	entry = get_irq_msi(dev->irq);
-	pos = entry->msi_attrib.pos;
+	entry = irq_get_msi_desc(dev->irq);
 
 	pci_intx_for_msi(dev, 0);
-	msi_set_enable(dev, pos, 0);
-	write_msi_msg(dev->irq, &entry->msg);
+	msi_set_enable(dev, 0);
+	arch_restore_msi_irqs(dev);
 
-	pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
+	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
 	msi_mask_irq(entry, msi_capable_mask(control), entry->masked);
 	control &= ~PCI_MSI_FLAGS_QSIZE;
 	control |= (entry->msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE;
-	pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
+	pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
 }
 
 static void __pci_restore_msix_state(struct pci_dev *dev)
 {
-	int pos;
 	struct msi_desc *entry;
 	u16 control;
 
 	if (!dev->msix_enabled)
 		return;
 	BUG_ON(list_empty(&dev->msi_list));
-	entry = list_entry(dev->msi_list.next, struct msi_desc, list);
-	pos = entry->msi_attrib.pos;
-	pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
+	entry = list_first_entry(&dev->msi_list, struct msi_desc, list);
+	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
 
 	/* route the table */
 	pci_intx_for_msi(dev, 0);
 	control |= PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL;
-	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
+	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);
 
+	arch_restore_msi_irqs(dev);
 	list_for_each_entry(entry, &dev->msi_list, list) {
-		write_msi_msg(entry->irq, &entry->msg);
 		msix_mask_irq(entry, entry->masked);
 	}
 
 	control &= ~PCI_MSIX_FLAGS_MASKALL;
-	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
+	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);
 }
 
 void pci_restore_msi_state(struct pci_dev *dev)
@@ -339,6 +498,102 @@ void pci_restore_msi_state(struct pci_dev *dev)
 }
 EXPORT_SYMBOL_GPL(pci_restore_msi_state);
 
+static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct msi_desc *entry;
+	unsigned long irq;
+	int retval;
+
+	retval = kstrtoul(attr->attr.name, 10, &irq);
+	if (retval)
+		return retval;
+
+	list_for_each_entry(entry, &pdev->msi_list, list) {
+		if (entry->irq == irq) {
+			return sprintf(buf, "%s\n",
+				       entry->msi_attrib.is_msix ? "msix" : "msi");
+		}
+	}
+	return -ENODEV;
+}
+
+static int populate_msi_sysfs(struct pci_dev *pdev)
+{
+	struct attribute **msi_attrs;
+	struct attribute *msi_attr;
+	struct device_attribute *msi_dev_attr;
+	struct attribute_group *msi_irq_group;
+	const struct attribute_group **msi_irq_groups;
+	struct msi_desc *entry;
+	int ret = -ENOMEM;
+	int num_msi = 0;
+	int count = 0;
+
+	/* Determine how many msi entries we have */
+	list_for_each_entry(entry, &pdev->msi_list, list) {
+		++num_msi;
+	}
+	if (!num_msi)
+		return 0;
+
+	/* Dynamically create the MSI attributes for the PCI device */
+	msi_attrs = kzalloc(sizeof(void *) * (num_msi + 1), GFP_KERNEL);
+	if (!msi_attrs)
+		return -ENOMEM;
+	list_for_each_entry(entry, &pdev->msi_list, list) {
+		msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL);
+		if (!msi_dev_attr)
+			goto error_attrs;
+		msi_attrs[count] = &msi_dev_attr->attr;
+
+		sysfs_attr_init(&msi_dev_attr->attr);
+		msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d",
+						    entry->irq);
+		if (!msi_dev_attr->attr.name)
+			goto error_attrs;
+		msi_dev_attr->attr.mode = S_IRUGO;
+		msi_dev_attr->show = msi_mode_show;
+		++count;
+	}
+
+	msi_irq_group = kzalloc(sizeof(*msi_irq_group), GFP_KERNEL);
+	if (!msi_irq_group)
+		goto error_attrs;
+	msi_irq_group->name = "msi_irqs";
+	msi_irq_group->attrs = msi_attrs;
+
+	msi_irq_groups = kzalloc(sizeof(void *) * 2, GFP_KERNEL);
+	if (!msi_irq_groups)
+		goto error_irq_group;
+	msi_irq_groups[0] = msi_irq_group;
+
+	ret = sysfs_create_groups(&pdev->dev.kobj, msi_irq_groups);
+	if (ret)
+		goto error_irq_groups;
+	pdev->msi_irq_groups = msi_irq_groups;
+
+	return 0;
+
+error_irq_groups:
+	kfree(msi_irq_groups);
+error_irq_group:
+	kfree(msi_irq_group);
+error_attrs:
+	count = 0;
+	msi_attr = msi_attrs[count];
+	while (msi_attr) {
+		msi_dev_attr = container_of(msi_attr, struct device_attribute, attr);
+		kfree(msi_attr->name);
+		kfree(msi_dev_attr);
+		++count;
+		msi_attr = msi_attrs[count];
+	}
+	kfree(msi_attrs);
+	return ret;
+}
+
 /**
  * msi_capability_init - configure device's MSI capability structure
  * @dev: pointer to the pci_dev data structure of MSI device function
@@ -353,27 +608,29 @@ EXPORT_SYMBOL_GPL(pci_restore_msi_state);
 static int msi_capability_init(struct pci_dev *dev, int nvec)
 {
 	struct msi_desc *entry;
-	int pos, ret;
+	int ret;
 	u16 control;
 	unsigned mask;
 
-   	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
-	msi_set_enable(dev, pos, 0);	/* Disable MSI during set up */
+	msi_set_enable(dev, 0);	/* Disable MSI during set up */
 
-	pci_read_config_word(dev, msi_control_reg(pos), &control);
+	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
 	/* MSI Entry Initialization */
 	entry = alloc_msi_entry(dev);
 	if (!entry)
 		return -ENOMEM;
 
-	entry->msi_attrib.is_msix = 0;
-	entry->msi_attrib.is_64 = is_64bit_address(control);
-	entry->msi_attrib.entry_nr = 0;
-	entry->msi_attrib.maskbit = is_mask_bit_support(control);
-	entry->msi_attrib.default_irq = dev->irq;	/* Save IOAPIC IRQ */
-	entry->msi_attrib.pos = pos;
-
-	entry->mask_pos = msi_mask_reg(pos, entry->msi_attrib.is_64);
+	entry->msi_attrib.is_msix	= 0;
+	entry->msi_attrib.is_64		= !!(control & PCI_MSI_FLAGS_64BIT);
+	entry->msi_attrib.entry_nr	= 0;
+	entry->msi_attrib.maskbit	= !!(control & PCI_MSI_FLAGS_MASKBIT);
+	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
+	entry->msi_attrib.pos		= dev->msi_cap;
+
+	if (control & PCI_MSI_FLAGS_64BIT)
+		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64;
+	else
+		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_32;
 	/* All MSIs are unmasked by default, Mask them all */
 	if (entry->msi_attrib.maskbit)
 		pci_read_config_dword(dev, entry->mask_pos, &entry->masked);
@@ -385,19 +642,90 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
 	/* Configure MSI capability structure */
 	ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
 	if (ret) {
-		msi_free_irqs(dev);
+		msi_mask_irq(entry, mask, ~mask);
+		free_msi_irqs(dev);
+		return ret;
+	}
+
+	ret = populate_msi_sysfs(dev);
+	if (ret) {
+		msi_mask_irq(entry, mask, ~mask);
+		free_msi_irqs(dev);
 		return ret;
 	}
 
 	/* Set MSI enabled bits	 */
 	pci_intx_for_msi(dev, 0);
-	msi_set_enable(dev, pos, 1);
+	msi_set_enable(dev, 1);
 	dev->msi_enabled = 1;
 
 	dev->irq = entry->irq;
 	return 0;
 }
 
+static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries)
+{
+	resource_size_t phys_addr;
+	u32 table_offset;
+	u8 bir;
+
+	pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE,
+			      &table_offset);
+	bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
+	table_offset &= PCI_MSIX_TABLE_OFFSET;
+	phys_addr = pci_resource_start(dev, bir) + table_offset;
+
+	return ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
+}
+
+static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
+			      struct msix_entry *entries, int nvec)
+{
+	struct msi_desc *entry;
+	int i;
+
+	for (i = 0; i < nvec; i++) {
+		entry = alloc_msi_entry(dev);
+		if (!entry) {
+			if (!i)
+				iounmap(base);
+			else
+				free_msi_irqs(dev);
+			/* No enough memory. Don't try again */
+			return -ENOMEM;
+		}
+
+		entry->msi_attrib.is_msix	= 1;
+		entry->msi_attrib.is_64		= 1;
+		entry->msi_attrib.entry_nr	= entries[i].entry;
+		entry->msi_attrib.default_irq	= dev->irq;
+		entry->msi_attrib.pos		= dev->msix_cap;
+		entry->mask_base		= base;
+
+		list_add_tail(&entry->list, &dev->msi_list);
+	}
+
+	return 0;
+}
+
+static void msix_program_entries(struct pci_dev *dev,
+				 struct msix_entry *entries)
+{
+	struct msi_desc *entry;
+	int i = 0;
+
+	list_for_each_entry(entry, &dev->msi_list, list) {
+		int offset = entries[i].entry * PCI_MSIX_ENTRY_SIZE +
+						PCI_MSIX_ENTRY_VECTOR_CTRL;
+
+		entries[i].vector = entry->irq;
+		irq_set_msi_desc(entry->irq, entry);
+		entry->masked = readl(entry->mask_base + offset);
+		msix_mask_irq(entry, 1);
+		i++;
+	}
+}
+
 /**
  * msix_capability_init - configure device's MSI-X capability
  * @dev: pointer to the pci_dev data structure of MSI-X device function
@@ -411,67 +739,28 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
 static int msix_capability_init(struct pci_dev *dev,
 				struct msix_entry *entries, int nvec)
 {
-	struct msi_desc *entry;
-	int pos, i, j, nr_entries, ret;
-	unsigned long phys_addr;
-	u32 table_offset;
- 	u16 control;
-	u8 bir;
+	int ret;
+	u16 control;
 	void __iomem *base;
 
-   	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
-	pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
+	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
 
 	/* Ensure MSI-X is disabled while it is set up */
 	control &= ~PCI_MSIX_FLAGS_ENABLE;
-	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
+	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);
 
 	/* Request & Map MSI-X table region */
-	nr_entries = multi_msix_capable(control);
-
- 	pci_read_config_dword(dev, msix_table_offset_reg(pos), &table_offset);
-	bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
-	table_offset &= ~PCI_MSIX_FLAGS_BIRMASK;
-	phys_addr = pci_resource_start (dev, bir) + table_offset;
-	base = ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
-	if (base == NULL)
+	base = msix_map_region(dev, msix_table_size(control));
+	if (!base)
 		return -ENOMEM;
 
-	for (i = 0; i < nvec; i++) {
-		entry = alloc_msi_entry(dev);
-		if (!entry)
-			break;
-
- 		j = entries[i].entry;
-		entry->msi_attrib.is_msix = 1;
-		entry->msi_attrib.is_64 = 1;
-		entry->msi_attrib.entry_nr = j;
-		entry->msi_attrib.default_irq = dev->irq;
-		entry->msi_attrib.pos = pos;
-		entry->mask_base = base;
-
-		list_add_tail(&entry->list, &dev->msi_list);
-	}
+	ret = msix_setup_entries(dev, base, entries, nvec);
+	if (ret)
+		return ret;
 
 	ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
-	if (ret < 0) {
-		/* If we had some success report the number of irqs
-		 * we succeeded in setting up. */
-		int avail = 0;
-		list_for_each_entry(entry, &dev->msi_list, list) {
-			if (entry->irq != 0) {
-				avail++;
-			}
-		}
-
-		if (avail != 0)
-			ret = avail;
-	}
-
-	if (ret) {
-		msi_free_irqs(dev);
-		return ret;
-	}
+	if (ret)
+		goto out_avail;
 
 	/*
 	 * Some devices require MSI-X to be enabled before we can touch the
@@ -479,27 +768,44 @@ static int msix_capability_init(struct pci_dev *dev,
 	 * interrupts coming in before they're fully set up.
 	 */
 	control |= PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE;
-	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
+	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);
 
-	i = 0;
-	list_for_each_entry(entry, &dev->msi_list, list) {
-		entries[i].vector = entry->irq;
-		set_irq_msi(entry->irq, entry);
-		j = entries[i].entry;
-		entry->masked = readl(base + j * PCI_MSIX_ENTRY_SIZE +
-					PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
-		msix_mask_irq(entry, 1);
-		i++;
-	}
+	msix_program_entries(dev, entries);
+
+	ret = populate_msi_sysfs(dev);
+	if (ret)
+		goto out_free;
 
 	/* Set MSI-X enabled bits and unmask the function */
 	pci_intx_for_msi(dev, 0);
 	dev->msix_enabled = 1;
 
 	control &= ~PCI_MSIX_FLAGS_MASKALL;
-	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
+	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);
 
 	return 0;
+
+out_avail:
+	if (ret < 0) {
+		/*
+		 * If we had some success, report the number of irqs
+		 * we succeeded in setting up.
+		 */
+		struct msi_desc *entry;
+		int avail = 0;
+
+		list_for_each_entry(entry, &dev->msi_list, list) {
+			if (entry->irq != 0)
+				avail++;
+		}
+		if (avail != 0)
+			ret = avail;
+	}
+
+out_free:
+	free_msi_irqs(dev);
+
+	return ret;
 }
 
 /**
@@ -508,11 +814,11 @@ static int msix_capability_init(struct pci_dev *dev,
  * @nvec: how many MSIs have been requested ?
  * @type: are we checking for MSI or MSI-X ?
  *
- * Look at global flags, the device itself, and its parent busses
+ * Look at global flags, the device itself, and its parent buses
  * to determine if MSI/-X are supported for the device. If MSI/-X is
  * supported return 0, else return an error code.
  **/
-static int pci_msi_check_device(struct pci_dev* dev, int nvec, int type)
+static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type)
 {
 	struct pci_bus *bus;
 	int ret;
@@ -529,8 +835,9 @@ static int pci_msi_check_device(struct pci_dev* dev, int nvec, int type)
 	if (nvec < 1)
 		return -ERANGE;
 
-	/* Any bridge which does NOT route MSI transactions from it's
-	 * secondary bus to it's primary bus must set NO_MSI flag on
+	/*
+	 * Any bridge which does NOT route MSI transactions from its
+	 * secondary bus to its primary bus must set NO_MSI flag on
 	 * the secondary pci_bus.
 	 * We expect only arch-specific PCI host bus controller driver
 	 * or quirks for specific PCI bridges to be setting NO_MSI.
@@ -543,143 +850,89 @@ static int pci_msi_check_device(struct pci_dev* dev, int nvec, int type)
 	if (ret)
 		return ret;
 
-	if (!pci_find_capability(dev, type))
-		return -EINVAL;
-
 	return 0;
 }
 
 /**
- * pci_enable_msi_block - configure device's MSI capability structure
- * @dev: device to configure
- * @nvec: number of interrupts to configure
+ * pci_msi_vec_count - Return the number of MSI vectors a device can send
+ * @dev: device to report about
  *
- * Allocate IRQs for a device with the MSI capability.
- * This function returns a negative errno if an error occurs.  If it
- * is unable to allocate the number of interrupts requested, it returns
- * the number of interrupts it might be able to allocate.  If it successfully
- * allocates at least the number of interrupts requested, it returns 0 and
- * updates the @dev's irq member to the lowest new interrupt number; the
- * other interrupt numbers allocated to this device are consecutive.
- */
-int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec)
+ * This function returns the number of MSI vectors a device requested via
+ * Multiple Message Capable register. It returns a negative errno if the
+ * device is not capable sending MSI interrupts. Otherwise, the call succeeds
+ * and returns a power of two, up to a maximum of 2^5 (32), according to the
+ * MSI specification.
+ **/
+int pci_msi_vec_count(struct pci_dev *dev)
 {
-	int status, pos, maxvec;
+	int ret;
 	u16 msgctl;
 
-	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
-	if (!pos)
+	if (!dev->msi_cap)
 		return -EINVAL;
-	pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl);
-	maxvec = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1);
-	if (nvec > maxvec)
-		return maxvec;
-
-	status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI);
-	if (status)
-		return status;
 
-	WARN_ON(!!dev->msi_enabled);
-
-	/* Check whether driver already requested MSI-X irqs */
-	if (dev->msix_enabled) {
-		dev_info(&dev->dev, "can't enable MSI "
-			 "(MSI-X already enabled)\n");
-		return -EINVAL;
-	}
+	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl);
+	ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1);
 
-	status = msi_capability_init(dev, nvec);
-	return status;
+	return ret;
 }
-EXPORT_SYMBOL(pci_enable_msi_block);
+EXPORT_SYMBOL(pci_msi_vec_count);
 
 void pci_msi_shutdown(struct pci_dev *dev)
 {
 	struct msi_desc *desc;
 	u32 mask;
 	u16 ctrl;
-	unsigned pos;
 
 	if (!pci_msi_enable || !dev || !dev->msi_enabled)
 		return;
 
 	BUG_ON(list_empty(&dev->msi_list));
 	desc = list_first_entry(&dev->msi_list, struct msi_desc, list);
-	pos = desc->msi_attrib.pos;
 
-	msi_set_enable(dev, pos, 0);
+	msi_set_enable(dev, 0);
 	pci_intx_for_msi(dev, 1);
 	dev->msi_enabled = 0;
 
-	pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &ctrl);
+	/* Return the device with MSI unmasked as initial states */
+	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &ctrl);
 	mask = msi_capable_mask(ctrl);
-	msi_mask_irq(desc, mask, ~mask);
+	/* Keep cached state to be restored */
+	arch_msi_mask_irq(desc, mask, ~mask);
 
 	/* Restore dev->irq to its default pin-assertion irq */
 	dev->irq = desc->msi_attrib.default_irq;
 }
 
-void pci_disable_msi(struct pci_dev* dev)
+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->msi_attrib.is_msix)
-		return;
-
-	msi_free_irqs(dev);
+	free_msi_irqs(dev);
 }
 EXPORT_SYMBOL(pci_disable_msi);
 
-static int msi_free_irqs(struct pci_dev* dev)
-{
-	struct msi_desc *entry, *tmp;
-
-	list_for_each_entry(entry, &dev->msi_list, list) {
-		int i, nvec;
-		if (!entry->irq)
-			continue;
-		nvec = 1 << entry->msi_attrib.multiple;
-		for (i = 0; i < nvec; i++)
-			BUG_ON(irq_has_action(entry->irq + i));
-	}
-
-	arch_teardown_msi_irqs(dev);
-
-	list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {
-		if (entry->msi_attrib.is_msix) {
-			msix_mask_irq(entry, 1);
-			if (list_is_last(&entry->list, &dev->msi_list))
-				iounmap(entry->mask_base);
-		}
-		list_del(&entry->list);
-		kfree(entry);
-	}
-
-	return 0;
-}
-
 /**
- * pci_msix_table_size - return the number of device's MSI-X table entries
+ * pci_msix_vec_count - return the number of device's MSI-X table entries
  * @dev: pointer to the pci_dev data structure of MSI-X device function
- */
-int pci_msix_table_size(struct pci_dev *dev)
+ * This function returns the number of device's MSI-X table entries and
+ * therefore the number of MSI-X vectors device is capable of sending.
+ * It returns a negative errno if the device is not capable of sending MSI-X
+ * interrupts.
+ **/
+int pci_msix_vec_count(struct pci_dev *dev)
 {
-	int pos;
 	u16 control;
 
-	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
-	if (!pos)
-		return 0;
+	if (!dev->msix_cap)
+		return -EINVAL;
 
-	pci_read_config_word(dev, msi_control_reg(pos), &control);
-	return multi_msix_capable(control);
+	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
+	return msix_table_size(control);
 }
+EXPORT_SYMBOL(pci_msix_vec_count);
 
 /**
  * pci_enable_msix - configure device's MSI-X capability structure
@@ -696,19 +949,21 @@ int pci_msix_table_size(struct pci_dev *dev)
  * of irqs or MSI-X vectors available. Driver should use the returned value to
  * re-send its request.
  **/
-int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
+int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
 {
 	int status, nr_entries;
 	int i, j;
 
-	if (!entries)
- 		return -EINVAL;
+	if (!entries || !dev->msix_cap || dev->current_state != PCI_D0)
+		return -EINVAL;
 
 	status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSIX);
 	if (status)
 		return status;
 
-	nr_entries = pci_msix_table_size(dev);
+	nr_entries = pci_msix_vec_count(dev);
+	if (nr_entries < 0)
+		return nr_entries;
 	if (nvec > nr_entries)
 		return nr_entries;
 
@@ -724,9 +979,8 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
 	WARN_ON(!!dev->msix_enabled);
 
 	/* Check whether driver already requested for MSI irq */
-   	if (dev->msi_enabled) {
-		dev_info(&dev->dev, "can't enable MSI-X "
-		       "(MSI IRQ already assigned)\n");
+	if (dev->msi_enabled) {
+		dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
 		return -EINVAL;
 	}
 	status = msix_capability_init(dev, entries, nvec);
@@ -734,28 +988,31 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
 }
 EXPORT_SYMBOL(pci_enable_msix);
 
-static void msix_free_all_irqs(struct pci_dev *dev)
+void pci_msix_shutdown(struct pci_dev *dev)
 {
-	msi_free_irqs(dev);
-}
+	struct msi_desc *entry;
 
-void pci_msix_shutdown(struct pci_dev* dev)
-{
 	if (!pci_msi_enable || !dev || !dev->msix_enabled)
 		return;
 
+	/* Return the device with MSI-X masked as initial states */
+	list_for_each_entry(entry, &dev->msi_list, list) {
+		/* Keep cached states to be restored */
+		arch_msix_mask_irq(entry, 1);
+	}
+
 	msix_set_enable(dev, 0);
 	pci_intx_for_msi(dev, 1);
 	dev->msix_enabled = 0;
 }
-void pci_disable_msix(struct pci_dev* dev)
+
+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);
+	free_msi_irqs(dev);
 }
 EXPORT_SYMBOL(pci_disable_msix);
 
@@ -768,16 +1025,13 @@ EXPORT_SYMBOL(pci_disable_msix);
  * allocated for this device function, are reclaimed to unused state,
  * which may be used later on.
  **/
-void msi_remove_pci_irq_vectors(struct pci_dev* dev)
+void msi_remove_pci_irq_vectors(struct pci_dev *dev)
 {
 	if (!pci_msi_enable || !dev)
- 		return;
-
-	if (dev->msi_enabled)
-		msi_free_irqs(dev);
+		return;
 
-	if (dev->msix_enabled)
-		msix_free_all_irqs(dev);
+	if (dev->msi_enabled || dev->msix_enabled)
+		free_msi_irqs(dev);
 }
 
 void pci_no_msi(void)
@@ -800,4 +1054,121 @@ EXPORT_SYMBOL(pci_msi_enabled);
 void pci_msi_init_pci_dev(struct pci_dev *dev)
 {
 	INIT_LIST_HEAD(&dev->msi_list);
+
+	/* Disable the msi hardware to avoid screaming interrupts
+	 * during boot.  This is the power on reset default so
+	 * usually this should be a noop.
+	 */
+	dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
+	if (dev->msi_cap)
+		msi_set_enable(dev, 0);
+
+	dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
+	if (dev->msix_cap)
+		msix_set_enable(dev, 0);
+}
+
+/**
+ * pci_enable_msi_range - configure device's MSI capability structure
+ * @dev: device to configure
+ * @minvec: minimal number of interrupts to configure
+ * @maxvec: maximum number of interrupts to configure
+ *
+ * This function tries to allocate a maximum possible number of interrupts in a
+ * range between @minvec and @maxvec. It returns a negative errno if an error
+ * occurs. If it succeeds, it returns the actual number of interrupts allocated
+ * and updates the @dev's irq member to the lowest new interrupt number;
+ * the other interrupt numbers allocated to this device are consecutive.
+ **/
+int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec)
+{
+	int nvec;
+	int rc;
+
+	if (dev->current_state != PCI_D0)
+		return -EINVAL;
+
+	WARN_ON(!!dev->msi_enabled);
+
+	/* Check whether driver already requested MSI-X irqs */
+	if (dev->msix_enabled) {
+		dev_info(&dev->dev,
+			 "can't enable MSI (MSI-X already enabled)\n");
+		return -EINVAL;
+	}
+
+	if (maxvec < minvec)
+		return -ERANGE;
+
+	nvec = pci_msi_vec_count(dev);
+	if (nvec < 0)
+		return nvec;
+	else if (nvec < minvec)
+		return -EINVAL;
+	else if (nvec > maxvec)
+		nvec = maxvec;
+
+	do {
+		rc = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI);
+		if (rc < 0) {
+			return rc;
+		} else if (rc > 0) {
+			if (rc < minvec)
+				return -ENOSPC;
+			nvec = rc;
+		}
+	} while (rc);
+
+	do {
+		rc = msi_capability_init(dev, nvec);
+		if (rc < 0) {
+			return rc;
+		} else if (rc > 0) {
+			if (rc < minvec)
+				return -ENOSPC;
+			nvec = rc;
+		}
+	} while (rc);
+
+	return nvec;
+}
+EXPORT_SYMBOL(pci_enable_msi_range);
+
+/**
+ * pci_enable_msix_range - configure device's MSI-X capability structure
+ * @dev: pointer to the pci_dev data structure of MSI-X device function
+ * @entries: pointer to an array of MSI-X entries
+ * @minvec: minimum number of MSI-X irqs requested
+ * @maxvec: maximum number of MSI-X irqs requested
+ *
+ * Setup the MSI-X capability structure of device function with a maximum
+ * possible number of interrupts in the range between @minvec and @maxvec
+ * upon its software driver call to request for MSI-X mode enabled on its
+ * hardware device function. It returns a negative errno if an error occurs.
+ * If it succeeds, it returns the actual number of interrupts allocated and
+ * indicates the successful configuration of MSI-X capability structure
+ * with new allocated MSI-X interrupts.
+ **/
+int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
+			       int minvec, int maxvec)
+{
+	int nvec = maxvec;
+	int rc;
+
+	if (maxvec < minvec)
+		return -ERANGE;
+
+	do {
+		rc = pci_enable_msix(dev, entries, nvec);
+		if (rc < 0) {
+			return rc;
+		} else if (rc > 0) {
+			if (rc < minvec)
+				return -ENOSPC;
+			nvec = rc;
+		}
+	} while (rc);
+
+	return nvec;
 }
+EXPORT_SYMBOL(pci_enable_msix_range);