From 0daf9878a7990058e74025493820bce0f67654c4 Mon Sep 17 00:00:00 2001 From: Tony Krowiak Date: Wed, 18 Jan 2023 15:31:07 -0500 Subject: [PATCH] s390/vfio_ap: check TAPQ response code when waiting for queue reset The vfio_ap_mdev_reset_queue() function does not check the status response code returned form the PQAP(TAPQ) function when verifying the queue's status; consequently, there is no way of knowing whether verification failed because the wait time was exceeded, or because the PQAP(TAPQ) failed. This patch adds a function to check the status response code from the PQAP(TAPQ) instruction and logs an appropriate message if it fails. Signed-off-by: Tony Krowiak Reviewed-by: Jason J. Herne Reviewed-by: Harald Freudenberger Link: https://lore.kernel.org/r/20230118203111.529766-3-akrowiak@linux.ibm.com Signed-off-by: Christian Borntraeger Signed-off-by: Heiko Carstens --- drivers/s390/crypto/vfio_ap_ops.c | 36 +++++++++++++++++++++++++++++++----- 1 file changed, 31 insertions(+), 5 deletions(-) diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index 785d079..7031e36 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -1598,23 +1598,49 @@ static struct vfio_ap_queue *vfio_ap_find_queue(int apqn) return q; } +static int apq_status_check(int apqn, struct ap_queue_status *status) +{ + switch (status->response_code) { + case AP_RESPONSE_NORMAL: + case AP_RESPONSE_RESET_IN_PROGRESS: + if (status->queue_empty && !status->irq_enabled) + return 0; + return -EBUSY; + case AP_RESPONSE_DECONFIGURED: + /* + * If the AP queue is deconfigured, any subsequent AP command + * targeting the queue will fail with the same response code. On the + * other hand, when an AP adapter is deconfigured, the associated + * queues are reset, so let's return a value indicating the reset + * for which we're waiting completed successfully. + */ + return 0; + default: + WARN(true, + "failed to verify reset of queue %02x.%04x: TAPQ rc=%u\n", + AP_QID_CARD(apqn), AP_QID_QUEUE(apqn), + status->response_code); + return -EIO; + } +} + static int apq_reset_check(struct vfio_ap_queue *q) { - int iters = 2; + int iters = 2, ret; struct ap_queue_status status; while (iters--) { msleep(20); status = ap_tapq(q->apqn, NULL); - if (status.queue_empty && !status.irq_enabled) - return 0; + ret = apq_status_check(q->apqn, &status); + if (ret != -EBUSY) + return ret; } WARN_ONCE(iters <= 0, "timeout verifying reset of queue %02x.%04x (%u, %u, %u)", AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn), status.queue_empty, status.irq_enabled, status.response_code); - - return -EBUSY; + return ret; } static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q, -- 2.7.4