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hisi_acc_vfio_pci: Use its own PCI reset_done error handler

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Register private handler for pci_error_handlers.reset_done and update
state accordingly.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Longfang Liu <liulongfang@huawei.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20220308184902.2242-10-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Shameer Kolothum 2022-03-08 18:49:02 +00:00 committed by Alex Williamson
parent b0eed08590
commit 4406f46c9b
2 changed files with 57 additions and 4 deletions
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57
drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
View file

@ -626,6 +626,27 @@ static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vde
}
}
/*
* This function is called in all state_mutex unlock cases to
* handle a 'deferred_reset' if exists.
*/
static void
hisi_acc_vf_state_mutex_unlock(struct hisi_acc_vf_core_device *hisi_acc_vdev)
{
again:
spin_lock(&hisi_acc_vdev->reset_lock);
if (hisi_acc_vdev->deferred_reset) {
hisi_acc_vdev->deferred_reset = false;
spin_unlock(&hisi_acc_vdev->reset_lock);
hisi_acc_vdev->vf_qm_state = QM_NOT_READY;
hisi_acc_vdev->mig_state = VFIO_DEVICE_STATE_RUNNING;
hisi_acc_vf_disable_fds(hisi_acc_vdev);
goto again;
}
mutex_unlock(&hisi_acc_vdev->state_mutex);
spin_unlock(&hisi_acc_vdev->reset_lock);
}
static void hisi_acc_vf_start_device(struct hisi_acc_vf_core_device *hisi_acc_vdev)
{
struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
@ -922,7 +943,7 @@ hisi_acc_vfio_pci_set_device_state(struct vfio_device *vdev,
break;
}
}
mutex_unlock(&hisi_acc_vdev->state_mutex);
hisi_acc_vf_state_mutex_unlock(hisi_acc_vdev);
return res;
}
@ -935,10 +956,35 @@ hisi_acc_vfio_pci_get_device_state(struct vfio_device *vdev,
mutex_lock(&hisi_acc_vdev->state_mutex);
*curr_state = hisi_acc_vdev->mig_state;
mutex_unlock(&hisi_acc_vdev->state_mutex);
hisi_acc_vf_state_mutex_unlock(hisi_acc_vdev);
return 0;
}
static void hisi_acc_vf_pci_aer_reset_done(struct pci_dev *pdev)
{
struct hisi_acc_vf_core_device *hisi_acc_vdev = dev_get_drvdata(&pdev->dev);
if (hisi_acc_vdev->core_device.vdev.migration_flags !=
VFIO_MIGRATION_STOP_COPY)
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(&hisi_acc_vdev->reset_lock);
hisi_acc_vdev->deferred_reset = true;
if (!mutex_trylock(&hisi_acc_vdev->state_mutex)) {
spin_unlock(&hisi_acc_vdev->reset_lock);
return;
}
spin_unlock(&hisi_acc_vdev->reset_lock);
hisi_acc_vf_state_mutex_unlock(hisi_acc_vdev);
}
static int hisi_acc_vf_qm_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
{
struct vfio_pci_core_device *vdev = &hisi_acc_vdev->core_device;
@ -1259,12 +1305,17 @@ static const struct pci_device_id hisi_acc_vfio_pci_table[] = {
MODULE_DEVICE_TABLE(pci, hisi_acc_vfio_pci_table);
static const struct pci_error_handlers hisi_acc_vf_err_handlers = {
.reset_done = hisi_acc_vf_pci_aer_reset_done,
.error_detected = vfio_pci_core_aer_err_detected,
};
static struct pci_driver hisi_acc_vfio_pci_driver = {
.name = KBUILD_MODNAME,
.id_table = hisi_acc_vfio_pci_table,
.probe = hisi_acc_vfio_pci_probe,
.remove = hisi_acc_vfio_pci_remove,
.err_handler = &vfio_pci_core_err_handlers,
.err_handler = &hisi_acc_vf_err_handlers,
};
module_pci_driver(hisi_acc_vfio_pci_driver);

4
drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
View file

@ -98,6 +98,7 @@ struct hisi_acc_vf_migration_file {
struct hisi_acc_vf_core_device {
struct vfio_pci_core_device core_device;
u8 deferred_reset:1;
/* for migration state */
struct mutex state_mutex;
enum vfio_device_mig_state mig_state;
@ -107,7 +108,8 @@ struct hisi_acc_vf_core_device {
struct hisi_qm vf_qm;
u32 vf_qm_state;
int vf_id;
/* for reset handler */
spinlock_t reset_lock;
struct hisi_acc_vf_migration_file *resuming_migf;
struct hisi_acc_vf_migration_file *saving_migf;
};