Commit 3c298b84 authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

Merge branch 'pci/vpd' 

- Ensure device is accessible before VPD access via sysfs (Alex Williamson)

- Ensure device doesn't go to a low-power state while we're polling for PME
  (Alex Williamson)

* pci/vpd:
  PCI: Fix runtime PM race with PME polling
  PCI/VPD: Add runtime power management to sysfs interface
parents 93a3241d d3fcd736

drivers/pci/pci.c

+16 −7
Original line number Diff line number Diff line
@@ -2420,10 +2420,13 @@ static void pci_pme_list_scan(struct work_struct *work) 


	mutex_lock(&pci_pme_list_mutex);

	list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {

		if (pme_dev->dev->pme_poll) {

			struct pci_dev *bridge;

		struct pci_dev *pdev = pme_dev->dev;



		if (pdev->pme_poll) {

			struct pci_dev *bridge = pdev->bus->self;

			struct device *dev = &pdev->dev;

			int pm_status;



			bridge = pme_dev->dev->bus->self;

			/*

			 * If bridge is in low power state, the

			 * configuration space of subordinate devices
@@ -2431,14 +2434,20 @@ static void pci_pme_list_scan(struct work_struct *work) 
			 */

			if (bridge && bridge->current_state != PCI_D0)

				continue;



			/*

			 * If the device is in D3cold it should not be

			 * polled either.

			 * If the device is in a low power state it

			 * should not be polled either.

			 */

			if (pme_dev->dev->current_state == PCI_D3cold)

			pm_status = pm_runtime_get_if_active(dev, true);

			if (!pm_status)

				continue;



			pci_pme_wakeup(pme_dev->dev, NULL);

			if (pdev->current_state != PCI_D3cold)

				pci_pme_wakeup(pdev, NULL);



			if (pm_status > 0)

				pm_runtime_put(dev);

		} else {

			list_del(&pme_dev->list);

			kfree(pme_dev);

drivers/pci/vpd.c

+32 −2
Original line number Diff line number Diff line
@@ -275,8 +275,23 @@ static ssize_t vpd_read(struct file *filp, struct kobject *kobj, 
			size_t count)

{

	struct pci_dev *dev = to_pci_dev(kobj_to_dev(kobj));

	struct pci_dev *vpd_dev = dev;

	ssize_t ret;



	if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) {

		vpd_dev = pci_get_func0_dev(dev);

		if (!vpd_dev)

			return -ENODEV;

	}



	pci_config_pm_runtime_get(vpd_dev);

	ret = pci_read_vpd(vpd_dev, off, count, buf);

	pci_config_pm_runtime_put(vpd_dev);



	return pci_read_vpd(dev, off, count, buf);

	if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0)

		pci_dev_put(vpd_dev);



	return ret;

}



static ssize_t vpd_write(struct file *filp, struct kobject *kobj,
@@ -284,8 +299,23 @@ static ssize_t vpd_write(struct file *filp, struct kobject *kobj, 
			 size_t count)

{

	struct pci_dev *dev = to_pci_dev(kobj_to_dev(kobj));

	struct pci_dev *vpd_dev = dev;

	ssize_t ret;



	if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) {

		vpd_dev = pci_get_func0_dev(dev);

		if (!vpd_dev)

			return -ENODEV;

	}



	pci_config_pm_runtime_get(vpd_dev);

	ret = pci_write_vpd(vpd_dev, off, count, buf);

	pci_config_pm_runtime_put(vpd_dev);



	return pci_write_vpd(dev, off, count, buf);

	if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0)

		pci_dev_put(vpd_dev);



	return ret;

}

static BIN_ATTR(vpd, 0600, vpd_read, vpd_write, 0);