Commit 27a9716b authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'vfio-v3.18-rc1' of git://github.com/awilliam/linux-vfio 

Pull VFIO updates from Alex Williamson:
 - Nested IOMMU extension to type1 (Will Deacon)
 - Restore MSIx message before enabling (Gavin Shan)
 - Fix remove path locking (Alex Williamson)

* tag 'vfio-v3.18-rc1' of git://github.com/awilliam/linux-vfio:
  vfio-pci: Fix remove path locking
  drivers/vfio: Export vfio_spapr_iommu_eeh_ioctl() with GPL
  vfio/pci: Restore MSIx message prior to enabling
  PCI: Export MSI message relevant functions
  vfio/iommu_type1: add new VFIO_TYPE1_NESTING_IOMMU IOMMU type
  iommu: introduce domain attribute for nesting IOMMUs
parents e98d6e7f 93899a67

drivers/pci/msi.c

+2 −0
Original line number Diff line number Diff line
@@ -302,6 +302,7 @@ void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg) 


	__get_cached_msi_msg(entry, msg);

}

EXPORT_SYMBOL_GPL(get_cached_msi_msg);



void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)

{
@@ -346,6 +347,7 @@ void write_msi_msg(unsigned int irq, struct msi_msg *msg) 


	__write_msi_msg(entry, msg);

}

EXPORT_SYMBOL_GPL(write_msi_msg);



static void free_msi_irqs(struct pci_dev *dev)

{

drivers/vfio/pci/vfio_pci.c

+57 −79
Original line number Diff line number Diff line
@@ -876,15 +876,11 @@ static void vfio_pci_remove(struct pci_dev *pdev) 
{

	struct vfio_pci_device *vdev;



	mutex_lock(&driver_lock);



	vdev = vfio_del_group_dev(&pdev->dev);

	if (vdev) {

		iommu_group_put(pdev->dev.iommu_group);

		kfree(vdev);

	}



	mutex_unlock(&driver_lock);

}



static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,
@@ -927,108 +923,90 @@ static struct pci_driver vfio_pci_driver = { 
	.err_handler	= &vfio_err_handlers,

};



/*

 * Test whether a reset is necessary and possible.  We mark devices as

 * needs_reset when they are released, but don't have a function-local reset

 * available.  If any of these exist in the affected devices, we want to do

 * a bus/slot reset.  We also need all of the affected devices to be unused,

 * so we abort if any device has a non-zero refcnt.  driver_lock prevents a

 * device from being opened during the scan or unbound from vfio-pci.

 */

static int vfio_pci_test_bus_reset(struct pci_dev *pdev, void *data)

{

	bool *needs_reset = data;

	struct pci_driver *pci_drv = ACCESS_ONCE(pdev->driver);

	int ret = -EBUSY;



	if (pci_drv == &vfio_pci_driver) {

		struct vfio_device *device;

		struct vfio_pci_device *vdev;



		device = vfio_device_get_from_dev(&pdev->dev);

		if (!device)

			return ret;



		vdev = vfio_device_data(device);

		if (vdev) {

			if (vdev->needs_reset)

				*needs_reset = true;



			if (!vdev->refcnt)

				ret = 0;

		}



		vfio_device_put(device);

	}



	/*

	 * TODO: vfio-core considers groups to be viable even if some devices

	 * are attached to known drivers, like pci-stub or pcieport.  We can't

	 * freeze devices from being unbound to those drivers like we can

	 * here though, so it would be racy to test for them.  We also can't

	 * use device_lock() to prevent changes as that would interfere with

	 * PCI-core taking device_lock during bus reset.  For now, we require

	 * devices to be bound to vfio-pci to get a bus/slot reset on release.

	 */



	return ret;

}

struct vfio_devices {

	struct vfio_device **devices;

	int cur_index;

	int max_index;

};



/* Clear needs_reset on all affected devices after successful bus/slot reset */

static int vfio_pci_clear_needs_reset(struct pci_dev *pdev, void *data)

static int vfio_pci_get_devs(struct pci_dev *pdev, void *data)

{

	struct vfio_devices *devs = data;

	struct pci_driver *pci_drv = ACCESS_ONCE(pdev->driver);



	if (pci_drv == &vfio_pci_driver) {

		struct vfio_device *device;

		struct vfio_pci_device *vdev;

	if (pci_drv != &vfio_pci_driver)

		return -EBUSY;



		device = vfio_device_get_from_dev(&pdev->dev);

		if (!device)

			return 0;



		vdev = vfio_device_data(device);

		if (vdev)

			vdev->needs_reset = false;

	if (devs->cur_index == devs->max_index)

		return -ENOSPC;



		vfio_device_put(device);

	}

	devs->devices[devs->cur_index] = vfio_device_get_from_dev(&pdev->dev);

	if (!devs->devices[devs->cur_index])

		return -EINVAL;



	devs->cur_index++;

	return 0;

}



/*

 * Attempt to do a bus/slot reset if there are devices affected by a reset for

 * this device that are needs_reset and all of the affected devices are unused

 * (!refcnt).  Callers of this function are required to hold driver_lock such

 * that devices can not be unbound from vfio-pci or opened by a user while we

 * test for and perform a bus/slot reset.

 * (!refcnt).  Callers are required to hold driver_lock when calling this to

 * prevent device opens and concurrent bus reset attempts.  We prevent device

 * unbinds by acquiring and holding a reference to the vfio_device.

 *

 * NB: vfio-core considers a group to be viable even if some devices are

 * bound to drivers like pci-stub or pcieport.  Here we require all devices

 * to be bound to vfio_pci since that's the only way we can be sure they

 * stay put.

 */

static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev)

{

	struct vfio_devices devs = { .cur_index = 0 };

	int i = 0, ret = -EINVAL;

	bool needs_reset = false, slot = false;

	int ret;

	struct vfio_pci_device *tmp;



	if (!pci_probe_reset_slot(vdev->pdev->slot))

		slot = true;

	else if (pci_probe_reset_bus(vdev->pdev->bus))

		return;



	if (vfio_pci_for_each_slot_or_bus(vdev->pdev,

					  vfio_pci_test_bus_reset,

					  &needs_reset, slot) || !needs_reset)

	if (vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_count_devs,

					  &i, slot) || !i)

		return;



	if (slot)

		ret = pci_try_reset_slot(vdev->pdev->slot);

	else

		ret = pci_try_reset_bus(vdev->pdev->bus);



	if (ret)

	devs.max_index = i;

	devs.devices = kcalloc(i, sizeof(struct vfio_device *), GFP_KERNEL);

	if (!devs.devices)

		return;



	vfio_pci_for_each_slot_or_bus(vdev->pdev,

				      vfio_pci_clear_needs_reset, NULL, slot);

	if (vfio_pci_for_each_slot_or_bus(vdev->pdev,

					  vfio_pci_get_devs, &devs, slot))

		goto put_devs;



	for (i = 0; i < devs.cur_index; i++) {

		tmp = vfio_device_data(devs.devices[i]);

		if (tmp->needs_reset)

			needs_reset = true;

		if (tmp->refcnt)

			goto put_devs;

	}



	if (needs_reset)

		ret = slot ? pci_try_reset_slot(vdev->pdev->slot) :

			     pci_try_reset_bus(vdev->pdev->bus);



put_devs:

	for (i = 0; i < devs.cur_index; i++) {

		if (!ret) {

			tmp = vfio_device_data(devs.devices[i]);

			tmp->needs_reset = false;

		}

		vfio_device_put(devs.devices[i]);

	}



	kfree(devs.devices);

}



static void __exit vfio_pci_cleanup(void)

drivers/vfio/pci/vfio_pci_intrs.c

+15 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <linux/device.h>

#include <linux/interrupt.h>

#include <linux/eventfd.h>

#include <linux/msi.h>

#include <linux/pci.h>

#include <linux/file.h>

#include <linux/poll.h>
@@ -548,6 +549,20 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev, 
		return PTR_ERR(trigger);

	}



	/*

	 * The MSIx vector table resides in device memory which may be cleared

	 * via backdoor resets. We don't allow direct access to the vector

	 * table so even if a userspace driver attempts to save/restore around

	 * such a reset it would be unsuccessful. To avoid this, restore the

	 * cached value of the message prior to enabling.

	 */

	if (msix) {

		struct msi_msg msg;



		get_cached_msi_msg(irq, &msg);

		write_msi_msg(irq, &msg);

	}



	ret = request_irq(irq, vfio_msihandler, 0,

			  vdev->ctx[vector].name, trigger);

	if (ret) {

drivers/vfio/vfio_iommu_type1.c

+25 −5
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ struct vfio_iommu { 
	struct mutex		lock;

	struct rb_root		dma_list;

	bool			v2;

	bool			nesting;

};



struct vfio_domain {
@@ -705,6 +706,15 @@ static int vfio_iommu_type1_attach_group(void *iommu_data, 
		goto out_free;

	}



	if (iommu->nesting) {

		int attr = 1;



		ret = iommu_domain_set_attr(domain->domain, DOMAIN_ATTR_NESTING,

					    &attr);

		if (ret)

			goto out_domain;

	}



	ret = iommu_attach_group(domain->domain, iommu_group);

	if (ret)

		goto out_domain;
@@ -819,17 +829,26 @@ static void *vfio_iommu_type1_open(unsigned long arg) 
{

	struct vfio_iommu *iommu;



	if (arg != VFIO_TYPE1_IOMMU && arg != VFIO_TYPE1v2_IOMMU)

		return ERR_PTR(-EINVAL);



	iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);

	if (!iommu)

		return ERR_PTR(-ENOMEM);



	switch (arg) {

	case VFIO_TYPE1_IOMMU:

		break;

	case VFIO_TYPE1_NESTING_IOMMU:

		iommu->nesting = true;

	case VFIO_TYPE1v2_IOMMU:

		iommu->v2 = true;

		break;

	default:

		kfree(iommu);

		return ERR_PTR(-EINVAL);

	}



	INIT_LIST_HEAD(&iommu->domain_list);

	iommu->dma_list = RB_ROOT;

	mutex_init(&iommu->lock);

	iommu->v2 = (arg == VFIO_TYPE1v2_IOMMU);



	return iommu;

}
@@ -885,6 +904,7 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, 
		switch (arg) {

		case VFIO_TYPE1_IOMMU:

		case VFIO_TYPE1v2_IOMMU:

		case VFIO_TYPE1_NESTING_IOMMU:

			return 1;

		case VFIO_DMA_CC_IOMMU:

			if (!iommu)

drivers/vfio/vfio_spapr_eeh.c

+1 −1
Original line number Diff line number Diff line
@@ -92,7 +92,7 @@ long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group, 


	return ret;

}

EXPORT_SYMBOL(vfio_spapr_iommu_eeh_ioctl);

EXPORT_SYMBOL_GPL(vfio_spapr_iommu_eeh_ioctl);



MODULE_VERSION(DRIVER_VERSION);

MODULE_LICENSE("GPL v2");

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