[PATCH v7 3/6] s390/pci: prepare is_passed_through() for dma-iommu

From: Niklas Schnelle
Date: Mon Feb 20 2023 - 10:23:00 EST


With the IOMMU always controlled through the IOMMU driver testing for
zdev->s390_domain is not a valid indication of the device being
passed-through. Instead test if zdev->kzdev is set.

Reviewed-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
Reviewed-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
---
arch/s390/pci/pci_event.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c
index b9324ca2eb94..4ef5a6a1d618 100644
--- a/arch/s390/pci/pci_event.c
+++ b/arch/s390/pci/pci_event.c
@@ -59,9 +59,16 @@ static inline bool ers_result_indicates_abort(pci_ers_result_t ers_res)
}
}

-static bool is_passed_through(struct zpci_dev *zdev)
+static bool is_passed_through(struct pci_dev *pdev)
{
- return zdev->s390_domain;
+ struct zpci_dev *zdev = to_zpci(pdev);
+ bool ret;
+
+ mutex_lock(&zdev->kzdev_lock);
+ ret = !!zdev->kzdev;
+ mutex_unlock(&zdev->kzdev_lock);
+
+ return ret;
}

static bool is_driver_supported(struct pci_driver *driver)
@@ -176,7 +183,7 @@ static pci_ers_result_t zpci_event_attempt_error_recovery(struct pci_dev *pdev)
}
pdev->error_state = pci_channel_io_frozen;

- if (is_passed_through(to_zpci(pdev))) {
+ if (is_passed_through(pdev)) {
pr_info("%s: Cannot be recovered in the host because it is a pass-through device\n",
pci_name(pdev));
goto out_unlock;
@@ -239,7 +246,7 @@ static void zpci_event_io_failure(struct pci_dev *pdev, pci_channel_state_t es)
* we will inject the error event and let the guest recover the device
* itself.
*/
- if (is_passed_through(to_zpci(pdev)))
+ if (is_passed_through(pdev))
goto out;
driver = to_pci_driver(pdev->dev.driver);
if (driver && driver->err_handler && driver->err_handler->error_detected)
--
2.37.2