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Commit cc8a44c6 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'vfio-v3.17-rc1' of git://github.com/awilliam/linux-vfio 

Pull VFIO updates from Alex Williamson:
 - enable support for bus reset on device release
 - fixes for EEH support

* tag 'vfio-v3.17-rc1' of git://github.com/awilliam/linux-vfio:
  drivers/vfio: Enable VFIO if EEH is not supported
  drivers/vfio: Allow EEH to be built as module
  drivers/vfio: Fix EEH build error
  vfio-pci: Attempt bus/slot reset on release
  vfio-pci: Use mutex around open, release, and remove
  vfio-pci: Release devices with BusMaster disabled
parents 4dacb91c 9b936c96

drivers/vfio/Kconfig

+6 −0
Original line number Diff line number Diff line
@@ -8,11 +8,17 @@ config VFIO_IOMMU_SPAPR_TCE 
	depends on VFIO && SPAPR_TCE_IOMMU

	default n



config VFIO_SPAPR_EEH

	tristate

	depends on EEH && VFIO_IOMMU_SPAPR_TCE

	default n



menuconfig VFIO

	tristate "VFIO Non-Privileged userspace driver framework"

	depends on IOMMU_API

	select VFIO_IOMMU_TYPE1 if X86

	select VFIO_IOMMU_SPAPR_TCE if (PPC_POWERNV || PPC_PSERIES)

	select VFIO_SPAPR_EEH if (PPC_POWERNV || PPC_PSERIES)

	select ANON_INODES

	help

	  VFIO provides a framework for secure userspace device drivers.

drivers/vfio/Makefile

+1 −1
Original line number Diff line number Diff line 
obj-$(CONFIG_VFIO) += vfio.o

obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o

obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o

obj-$(CONFIG_EEH) += vfio_spapr_eeh.o

obj-$(CONFIG_VFIO_SPAPR_EEH) += vfio_spapr_eeh.o

obj-$(CONFIG_VFIO_PCI) += pci/

drivers/vfio/pci/vfio_pci.c

+143 −18
Original line number Diff line number Diff line
@@ -37,6 +37,10 @@ module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR); 
MODULE_PARM_DESC(nointxmask,

		  "Disable support for PCI 2.3 style INTx masking.  If this resolves problems for specific devices, report lspci -vvvxxx to linux-pci@vger.kernel.org so the device can be fixed automatically via the broken_intx_masking flag.");



static DEFINE_MUTEX(driver_lock);



static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev);



static int vfio_pci_enable(struct vfio_pci_device *vdev)

{

	struct pci_dev *pdev = vdev->pdev;
@@ -44,6 +48,9 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev) 
	u16 cmd;

	u8 msix_pos;



	/* Don't allow our initial saved state to include busmaster */

	pci_clear_master(pdev);



	ret = pci_enable_device(pdev);

	if (ret)

		return ret;
@@ -99,7 +106,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev) 
	struct pci_dev *pdev = vdev->pdev;

	int bar;



	pci_disable_device(pdev);

	/* Stop the device from further DMA */

	pci_clear_master(pdev);



	vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE |

				VFIO_IRQ_SET_ACTION_TRIGGER,
@@ -117,6 +125,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev) 
		vdev->barmap[bar] = NULL;

	}



	vdev->needs_reset = true;



	/*

	 * If we have saved state, restore it.  If we can reset the device,

	 * even better.  Resetting with current state seems better than
@@ -128,7 +138,7 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev) 
			__func__, dev_name(&pdev->dev));



		if (!vdev->reset_works)

			return;

			goto out;



		pci_save_state(pdev);

	}
@@ -148,45 +158,54 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev) 
		if (ret)

			pr_warn("%s: Failed to reset device %s (%d)\n",

				__func__, dev_name(&pdev->dev), ret);

		else

			vdev->needs_reset = false;

	}



	pci_restore_state(pdev);

out:

	pci_disable_device(pdev);



	vfio_pci_try_bus_reset(vdev);

}



static void vfio_pci_release(void *device_data)

{

	struct vfio_pci_device *vdev = device_data;



	if (atomic_dec_and_test(&vdev->refcnt)) {

	mutex_lock(&driver_lock);



	if (!(--vdev->refcnt)) {

		vfio_spapr_pci_eeh_release(vdev->pdev);

		vfio_pci_disable(vdev);

	}



	mutex_unlock(&driver_lock);



	module_put(THIS_MODULE);

}



static int vfio_pci_open(void *device_data)

{

	struct vfio_pci_device *vdev = device_data;

	int ret;

	int ret = 0;



	if (!try_module_get(THIS_MODULE))

		return -ENODEV;



	if (atomic_inc_return(&vdev->refcnt) == 1) {

	mutex_lock(&driver_lock);



	if (!vdev->refcnt) {

		ret = vfio_pci_enable(vdev);

		if (ret)

			goto error;



		ret = vfio_spapr_pci_eeh_open(vdev->pdev);

		if (ret) {

			vfio_pci_disable(vdev);

			goto error;

		}

		vfio_spapr_pci_eeh_open(vdev->pdev);

	}



	return 0;

	vdev->refcnt++;

error:

	mutex_unlock(&driver_lock);

	if (ret)

		module_put(THIS_MODULE);

	return ret;

}
@@ -843,7 +862,6 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) 
	vdev->irq_type = VFIO_PCI_NUM_IRQS;

	mutex_init(&vdev->igate);

	spin_lock_init(&vdev->irqlock);

	atomic_set(&vdev->refcnt, 0);



	ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev);

	if (ret) {
@@ -858,14 +876,17 @@ static void vfio_pci_remove(struct pci_dev *pdev) 
{

	struct vfio_pci_device *vdev;



	vdev = vfio_del_group_dev(&pdev->dev);

	if (!vdev)

		return;

	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,

						  pci_channel_state_t state)

{
@@ -906,6 +927,110 @@ 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;

}



/* 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)

{

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



	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 0;



		vdev = vfio_device_data(device);

		if (vdev)

			vdev->needs_reset = false;



		vfio_device_put(device);

	}



	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.

 */

static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev)

{

	bool needs_reset = false, slot = false;

	int ret;



	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)

		return;



	if (slot)

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

	else

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



	if (ret)

		return;



	vfio_pci_for_each_slot_or_bus(vdev->pdev,

				      vfio_pci_clear_needs_reset, NULL, slot);

}



static void __exit vfio_pci_cleanup(void)

{

	pci_unregister_driver(&vfio_pci_driver);

drivers/vfio/pci/vfio_pci_private.h

+2 −1
Original line number Diff line number Diff line
@@ -54,8 +54,9 @@ struct vfio_pci_device { 
	bool			extended_caps;

	bool			bardirty;

	bool			has_vga;

	bool			needs_reset;

	struct pci_saved_state	*pci_saved_state;

	atomic_t		refcnt;

	int			refcnt;

	struct eventfd_ctx	*err_trigger;

};

drivers/vfio/vfio_spapr_eeh.c

+15 −2
Original line number Diff line number Diff line
@@ -9,20 +9,27 @@ 
 * published by the Free Software Foundation.

 */



#include <linux/module.h>

#include <linux/uaccess.h>

#include <linux/vfio.h>

#include <asm/eeh.h>



#define DRIVER_VERSION	"0.1"

#define DRIVER_AUTHOR	"Gavin Shan, IBM Corporation"

#define DRIVER_DESC	"VFIO IOMMU SPAPR EEH"



/* We might build address mapping here for "fast" path later */

int vfio_spapr_pci_eeh_open(struct pci_dev *pdev)

void vfio_spapr_pci_eeh_open(struct pci_dev *pdev)

{

	return eeh_dev_open(pdev);

	eeh_dev_open(pdev);

}

EXPORT_SYMBOL_GPL(vfio_spapr_pci_eeh_open);



void vfio_spapr_pci_eeh_release(struct pci_dev *pdev)

{

	eeh_dev_release(pdev);

}

EXPORT_SYMBOL_GPL(vfio_spapr_pci_eeh_release);



long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,

				unsigned int cmd, unsigned long arg)
@@ -85,3 +92,9 @@ long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group, 


	return ret;

}

EXPORT_SYMBOL(vfio_spapr_iommu_eeh_ioctl);



MODULE_VERSION(DRIVER_VERSION);

MODULE_LICENSE("GPL v2");

MODULE_AUTHOR(DRIVER_AUTHOR);

MODULE_DESCRIPTION(DRIVER_DESC);