Move the migration device state reset code from .reset_done() to dedicated callback. Remove the deferred reset mechanism, as it's no longer needed. Signed-off-by: Michał Winiarski --- drivers/vfio/pci/virtio/common.h | 3 -- drivers/vfio/pci/virtio/main.c | 1 - drivers/vfio/pci/virtio/migrate.c | 71 +++++++++---------------------- 3 files changed, 21 insertions(+), 54 deletions(-) diff --git a/drivers/vfio/pci/virtio/common.h b/drivers/vfio/pci/virtio/common.h index c7d7e27af386e..cb27d3d2d3bb9 100644 --- a/drivers/vfio/pci/virtio/common.h +++ b/drivers/vfio/pci/virtio/common.h @@ -92,12 +92,9 @@ struct virtiovf_pci_core_device { /* LM related */ u8 migrate_cap:1; - u8 deferred_reset:1; /* protect migration state */ struct mutex state_mutex; enum vfio_device_mig_state mig_state; - /* protect the reset_done flow */ - spinlock_t reset_lock; struct virtiovf_migration_file *resuming_migf; struct virtiovf_migration_file *saving_migf; }; diff --git a/drivers/vfio/pci/virtio/main.c b/drivers/vfio/pci/virtio/main.c index 8084f3e36a9f7..b80cb740f9a5d 100644 --- a/drivers/vfio/pci/virtio/main.c +++ b/drivers/vfio/pci/virtio/main.c @@ -203,7 +203,6 @@ static void virtiovf_pci_aer_reset_done(struct pci_dev *pdev) #ifdef CONFIG_VIRTIO_VFIO_PCI_ADMIN_LEGACY virtiovf_legacy_io_reset_done(pdev); #endif - virtiovf_migration_reset_done(pdev); } static const struct pci_error_handlers virtiovf_err_handlers = { diff --git a/drivers/vfio/pci/virtio/migrate.c b/drivers/vfio/pci/virtio/migrate.c index 7dd0ac866461d..5c7f9091d84e8 100644 --- a/drivers/vfio/pci/virtio/migrate.c +++ b/drivers/vfio/pci/virtio/migrate.c @@ -247,49 +247,6 @@ static void virtiovf_disable_fds(struct virtiovf_pci_core_device *virtvdev) } } -/* - * This function is called in all state_mutex unlock cases to - * handle a 'deferred_reset' if exists. - */ -static void virtiovf_state_mutex_unlock(struct virtiovf_pci_core_device *virtvdev) -{ -again: - spin_lock(&virtvdev->reset_lock); - if (virtvdev->deferred_reset) { - virtvdev->deferred_reset = false; - spin_unlock(&virtvdev->reset_lock); - virtvdev->mig_state = VFIO_DEVICE_STATE_RUNNING; - virtiovf_disable_fds(virtvdev); - goto again; - } - mutex_unlock(&virtvdev->state_mutex); - spin_unlock(&virtvdev->reset_lock); -} - -void virtiovf_migration_reset_done(struct pci_dev *pdev) -{ - struct virtiovf_pci_core_device *virtvdev = dev_get_drvdata(&pdev->dev); - - if (!virtvdev->migrate_cap) - return; - - /* - * As the higher VFIO layers are holding locks across reset and using - * those same locks with the mm_lock we need to prevent ABBA deadlock - * with the state_mutex and mm_lock. - * In case the state_mutex was taken already we defer the cleanup work - * to the unlock flow of the other running context. - */ - spin_lock(&virtvdev->reset_lock); - virtvdev->deferred_reset = true; - if (!mutex_trylock(&virtvdev->state_mutex)) { - spin_unlock(&virtvdev->reset_lock); - return; - } - spin_unlock(&virtvdev->reset_lock); - virtiovf_state_mutex_unlock(virtvdev); -} - static int virtiovf_release_file(struct inode *inode, struct file *filp) { struct virtiovf_migration_file *migf = filp->private_data; @@ -513,7 +470,7 @@ static long virtiovf_precopy_ioctl(struct file *filp, unsigned int cmd, goto err_state_unlock; done: - virtiovf_state_mutex_unlock(virtvdev); + mutex_unlock(&virtvdev->state_mutex); if (copy_to_user((void __user *)arg, &info, minsz)) return -EFAULT; return 0; @@ -521,7 +478,7 @@ static long virtiovf_precopy_ioctl(struct file *filp, unsigned int cmd, err_migf_unlock: mutex_unlock(&migf->lock); err_state_unlock: - virtiovf_state_mutex_unlock(virtvdev); + mutex_unlock(&virtvdev->state_mutex); return ret; } @@ -1048,7 +1005,7 @@ static ssize_t virtiovf_resume_write(struct file *filp, const char __user *buf, if (ret) migf->state = VIRTIOVF_MIGF_STATE_ERROR; mutex_unlock(&migf->lock); - virtiovf_state_mutex_unlock(migf->virtvdev); + mutex_unlock(&migf->virtvdev->state_mutex); return ret ? ret : done; } @@ -1245,7 +1202,7 @@ virtiovf_pci_set_device_state(struct vfio_device *vdev, break; } } - virtiovf_state_mutex_unlock(virtvdev); + mutex_unlock(&virtvdev->state_mutex); return res; } @@ -1257,10 +1214,24 @@ static int virtiovf_pci_get_device_state(struct vfio_device *vdev, mutex_lock(&virtvdev->state_mutex); *curr_state = virtvdev->mig_state; - virtiovf_state_mutex_unlock(virtvdev); + mutex_unlock(&virtvdev->state_mutex); return 0; } +static void virtiovf_pci_reset_device_state(struct vfio_device *vdev) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + vdev, struct virtiovf_pci_core_device, core_device.vdev); + + if (!virtvdev->migrate_cap) + return; + + mutex_lock(&virtvdev->state_mutex); + virtvdev->mig_state = VFIO_DEVICE_STATE_RUNNING; + virtiovf_disable_fds(virtvdev); + mutex_unlock(&virtvdev->state_mutex); +} + static int virtiovf_pci_get_data_size(struct vfio_device *vdev, unsigned long *stop_copy_length) { @@ -1297,13 +1268,14 @@ static int virtiovf_pci_get_data_size(struct vfio_device *vdev, if (!obj_id_exists) virtiovf_pci_free_obj_id(virtvdev, obj_id); end: - virtiovf_state_mutex_unlock(virtvdev); + mutex_unlock(&virtvdev->state_mutex); return ret; } static const struct vfio_migration_ops virtvdev_pci_mig_ops = { .migration_set_state = virtiovf_pci_set_device_state, .migration_get_state = virtiovf_pci_get_device_state, + .migration_reset_state = virtiovf_pci_reset_device_state, .migration_get_data_size = virtiovf_pci_get_data_size, }; @@ -1311,7 +1283,6 @@ void virtiovf_set_migratable(struct virtiovf_pci_core_device *virtvdev) { virtvdev->migrate_cap = 1; mutex_init(&virtvdev->state_mutex); - spin_lock_init(&virtvdev->reset_lock); virtvdev->core_device.vdev.migration_flags = VFIO_MIGRATION_STOP_COPY | VFIO_MIGRATION_P2P | -- 2.51.2