diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c index e301092e94ef..b7bb16f92ac6 100644 --- a/drivers/vfio/pci/vfio_pci_core.c +++ b/drivers/vfio/pci/vfio_pci_core.c @@ -228,6 +228,19 @@ int vfio_pci_set_power_state(struct vfio_pci_core_device *vdev, pci_power_t stat if (!ret) { /* D3 might be unsupported via quirk, skip unless in D3 */ if (needs_save && pdev->current_state >= PCI_D3hot) { + /* + * The current PCI state will be saved locally in + * 'pm_save' during the D3hot transition. When the + * device state is changed to D0 again with the current + * function, then pci_store_saved_state() will restore + * the state and will free the memory pointed by + * 'pm_save'. There are few cases where the PCI power + * state can be changed to D0 without the involvement + * of the driver. For these cases, free the earlier + * allocated memory first before overwriting 'pm_save' + * to prevent the memory leak. + */ + kfree(vdev->pm_save); vdev->pm_save = pci_store_saved_state(pdev); } else if (needs_restore) { pci_load_and_free_saved_state(pdev, &vdev->pm_save); @@ -322,6 +335,17 @@ void vfio_pci_core_disable(struct vfio_pci_core_device *vdev) /* For needs_reset */ lockdep_assert_held(&vdev->vdev.dev_set->lock); + /* + * This function can be invoked while the power state is non-D0. + * This function calls __pci_reset_function_locked() which internally + * can use pci_pm_reset() for the function reset. pci_pm_reset() will + * fail if the power state is non-D0. Also, for the devices which + * have NoSoftRst-, the reset function can cause the PCI config space + * reset without restoring the original state (saved locally in + * 'vdev->pm_save'). + */ + vfio_pci_set_power_state(vdev, PCI_D0); + /* Stop the device from further DMA */ pci_clear_master(pdev); @@ -921,6 +945,19 @@ long vfio_pci_core_ioctl(struct vfio_device *core_vdev, unsigned int cmd, return -EINVAL; vfio_pci_zap_and_down_write_memory_lock(vdev); + + /* + * This function can be invoked while the power state is non-D0. + * If pci_try_reset_function() has been called while the power + * state is non-D0, then pci_try_reset_function() will + * internally set the power state to D0 without vfio driver + * involvement. For the devices which have NoSoftRst-, the + * reset function can cause the PCI config space reset without + * restoring the original state (saved locally in + * 'vdev->pm_save'). + */ + vfio_pci_set_power_state(vdev, PCI_D0); + ret = pci_try_reset_function(vdev->pdev); up_write(&vdev->memory_lock); @@ -2036,6 +2073,18 @@ static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set, } cur_mem = NULL; + /* + * The pci_reset_bus() will reset all the devices in the bus. + * The power state can be non-D0 for some of the devices in the bus. + * For these devices, the pci_reset_bus() will internally set + * the power state to D0 without vfio driver involvement. + * For the devices which have NoSoftRst-, the reset function can + * cause the PCI config space reset without restoring the original + * state (saved locally in 'vdev->pm_save'). + */ + list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) + vfio_pci_set_power_state(cur, PCI_D0); + ret = pci_reset_bus(pdev); err_undo: @@ -2089,6 +2138,18 @@ static bool vfio_pci_dev_set_try_reset(struct vfio_device_set *dev_set) if (!pdev) return false; + /* + * The pci_reset_bus() will reset all the devices in the bus. + * The power state can be non-D0 for some of the devices in the bus. + * For these devices, the pci_reset_bus() will internally set + * the power state to D0 without vfio driver involvement. + * For the devices which have NoSoftRst-, the reset function can + * cause the PCI config space reset without restoring the original + * state (saved locally in 'vdev->pm_save'). + */ + list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) + vfio_pci_set_power_state(cur, PCI_D0); + ret = pci_reset_bus(pdev); if (ret) return false; diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c b/drivers/vfio/pci/vfio_pci_rdwr.c index 57d3b2cbbd8e..82ac1569deb0 100644 --- a/drivers/vfio/pci/vfio_pci_rdwr.c +++ b/drivers/vfio/pci/vfio_pci_rdwr.c @@ -288,6 +288,7 @@ out: return done; } +#ifdef CONFIG_VFIO_PCI_VGA ssize_t vfio_pci_vga_rw(struct vfio_pci_core_device *vdev, char __user *buf, size_t count, loff_t *ppos, bool iswrite) { @@ -355,6 +356,7 @@ ssize_t vfio_pci_vga_rw(struct vfio_pci_core_device *vdev, char __user *buf, return done; } +#endif static void vfio_pci_ioeventfd_do_write(struct vfio_pci_ioeventfd *ioeventfd, bool test_mem) diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h index 9f1bf8e49d43..74a4a0f17b28 100644 --- a/include/linux/vfio_pci_core.h +++ b/include/linux/vfio_pci_core.h @@ -159,8 +159,17 @@ extern ssize_t vfio_pci_config_rw(struct vfio_pci_core_device *vdev, extern ssize_t vfio_pci_bar_rw(struct vfio_pci_core_device *vdev, char __user *buf, size_t count, loff_t *ppos, bool iswrite); +#ifdef CONFIG_VFIO_PCI_VGA extern ssize_t vfio_pci_vga_rw(struct vfio_pci_core_device *vdev, char __user *buf, size_t count, loff_t *ppos, bool iswrite); +#else +static inline ssize_t vfio_pci_vga_rw(struct vfio_pci_core_device *vdev, + char __user *buf, size_t count, + loff_t *ppos, bool iswrite) +{ + return -EINVAL; +} +#endif extern long vfio_pci_ioeventfd(struct vfio_pci_core_device *vdev, loff_t offset, uint64_t data, int count, int fd);