From: Tony Krowiak akrowiak@linux.ibm.com
commit 6c12a6384e0c0b96debd88b24028e58f2ebd417b upstream.
The queues assigned to a matrix mediated device are currently reset when:
* The VFIO_DEVICE_RESET ioctl is invoked * The mdev fd is closed by userspace (QEMU) * The mdev is removed from sysfs.
Immediately after the reset of a queue, a call is made to disable interrupts for the queue. This is entirely unnecessary because the reset of a queue disables interrupts, so this will be removed.
Furthermore, vfio_ap_irq_disable() does an unconditional PQAP/AQIC which can result in a specification exception (when the corresponding facility is not available), so this is actually a bugfix.
Signed-off-by: Tony Krowiak akrowiak@linux.ibm.com [pasic@linux.ibm.com: minor rework before merging] Signed-off-by: Halil Pasic pasic@linux.ibm.com Fixes: ec89b55e3bce ("s390: ap: implement PAPQ AQIC interception in kernel") Cc: stable@vger.kernel.org Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/s390/crypto/vfio_ap_drv.c | 6 -- drivers/s390/crypto/vfio_ap_ops.c | 100 +++++++++++++++++++++------------- drivers/s390/crypto/vfio_ap_private.h | 12 ++-- 3 files changed, 69 insertions(+), 49 deletions(-)
--- a/drivers/s390/crypto/vfio_ap_drv.c +++ b/drivers/s390/crypto/vfio_ap_drv.c @@ -71,15 +71,11 @@ static int vfio_ap_queue_dev_probe(struc static void vfio_ap_queue_dev_remove(struct ap_device *apdev) { struct vfio_ap_queue *q; - int apid, apqi;
mutex_lock(&matrix_dev->lock); q = dev_get_drvdata(&apdev->device); + vfio_ap_mdev_reset_queue(q, 1); dev_set_drvdata(&apdev->device, NULL); - apid = AP_QID_CARD(q->apqn); - apqi = AP_QID_QUEUE(q->apqn); - vfio_ap_mdev_reset_queue(apid, apqi, 1); - vfio_ap_irq_disable(q); kfree(q); mutex_unlock(&matrix_dev->lock); } --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -25,6 +25,7 @@ #define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device"
static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev); +static struct vfio_ap_queue *vfio_ap_find_queue(int apqn);
static int match_apqn(struct device *dev, const void *data) { @@ -49,20 +50,15 @@ static struct vfio_ap_queue *vfio_ap_get int apqn) { struct vfio_ap_queue *q; - struct device *dev;
if (!test_bit_inv(AP_QID_CARD(apqn), matrix_mdev->matrix.apm)) return NULL; if (!test_bit_inv(AP_QID_QUEUE(apqn), matrix_mdev->matrix.aqm)) return NULL;
- dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL, - &apqn, match_apqn); - if (!dev) - return NULL; - q = dev_get_drvdata(dev); - q->matrix_mdev = matrix_mdev; - put_device(dev); + q = vfio_ap_find_queue(apqn); + if (q) + q->matrix_mdev = matrix_mdev;
return q; } @@ -119,13 +115,18 @@ static void vfio_ap_wait_for_irqclear(in */ static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q) { - if (q->saved_isc != VFIO_AP_ISC_INVALID && q->matrix_mdev) + if (!q) + return; + if (q->saved_isc != VFIO_AP_ISC_INVALID && + !WARN_ON(!(q->matrix_mdev && q->matrix_mdev->kvm))) { kvm_s390_gisc_unregister(q->matrix_mdev->kvm, q->saved_isc); - if (q->saved_pfn && q->matrix_mdev) + q->saved_isc = VFIO_AP_ISC_INVALID; + } + if (q->saved_pfn && !WARN_ON(!q->matrix_mdev)) { vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev), &q->saved_pfn, 1); - q->saved_pfn = 0; - q->saved_isc = VFIO_AP_ISC_INVALID; + q->saved_pfn = 0; + } }
/** @@ -144,7 +145,7 @@ static void vfio_ap_free_aqic_resources( * Returns if ap_aqic function failed with invalid, deconfigured or * checkstopped AP. */ -struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q) +static struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q) { struct ap_qirq_ctrl aqic_gisa = {}; struct ap_queue_status status; @@ -1114,48 +1115,70 @@ static int vfio_ap_mdev_group_notifier(s return NOTIFY_OK; }
-static void vfio_ap_irq_disable_apqn(int apqn) +static struct vfio_ap_queue *vfio_ap_find_queue(int apqn) { struct device *dev; - struct vfio_ap_queue *q; + struct vfio_ap_queue *q = NULL;
dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL, &apqn, match_apqn); if (dev) { q = dev_get_drvdata(dev); - vfio_ap_irq_disable(q); put_device(dev); } + + return q; }
-int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi, +int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q, unsigned int retry) { struct ap_queue_status status; + int ret; int retry2 = 2; - int apqn = AP_MKQID(apid, apqi);
- do { - status = ap_zapq(apqn); - switch (status.response_code) { - case AP_RESPONSE_NORMAL: - while (!status.queue_empty && retry2--) { - msleep(20); - status = ap_tapq(apqn, NULL); - } - WARN_ON_ONCE(retry2 <= 0); - return 0; - case AP_RESPONSE_RESET_IN_PROGRESS: - case AP_RESPONSE_BUSY: + if (!q) + return 0; + +retry_zapq: + status = ap_zapq(q->apqn); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + ret = 0; + break; + case AP_RESPONSE_RESET_IN_PROGRESS: + if (retry--) { msleep(20); - break; - default: - /* things are really broken, give up */ - return -EIO; + goto retry_zapq; } - } while (retry--); + ret = -EBUSY; + break; + case AP_RESPONSE_Q_NOT_AVAIL: + case AP_RESPONSE_DECONFIGURED: + case AP_RESPONSE_CHECKSTOPPED: + WARN_ON_ONCE(status.irq_enabled); + ret = -EBUSY; + goto free_resources; + default: + /* things are really broken, give up */ + WARN(true, "PQAP/ZAPQ completed with invalid rc (%x)\n", + status.response_code); + return -EIO; + } + + /* wait for the reset to take effect */ + while (retry2--) { + if (status.queue_empty && !status.irq_enabled) + break; + msleep(20); + status = ap_tapq(q->apqn, NULL); + } + WARN_ON_ONCE(retry2 <= 0);
- return -EBUSY; +free_resources: + vfio_ap_free_aqic_resources(q); + + return ret; }
static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev) @@ -1163,13 +1186,15 @@ static int vfio_ap_mdev_reset_queues(str int ret; int rc = 0; unsigned long apid, apqi; + struct vfio_ap_queue *q; struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, matrix_mdev->matrix.apm_max + 1) { for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, matrix_mdev->matrix.aqm_max + 1) { - ret = vfio_ap_mdev_reset_queue(apid, apqi, 1); + q = vfio_ap_find_queue(AP_MKQID(apid, apqi)); + ret = vfio_ap_mdev_reset_queue(q, 1); /* * Regardless whether a queue turns out to be busy, or * is not operational, we need to continue resetting @@ -1177,7 +1202,6 @@ static int vfio_ap_mdev_reset_queues(str */ if (ret) rc = ret; - vfio_ap_irq_disable_apqn(AP_MKQID(apid, apqi)); } }
--- a/drivers/s390/crypto/vfio_ap_private.h +++ b/drivers/s390/crypto/vfio_ap_private.h @@ -88,11 +88,6 @@ struct ap_matrix_mdev { struct mdev_device *mdev; };
-extern int vfio_ap_mdev_register(void); -extern void vfio_ap_mdev_unregister(void); -int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi, - unsigned int retry); - struct vfio_ap_queue { struct ap_matrix_mdev *matrix_mdev; unsigned long saved_pfn; @@ -100,5 +95,10 @@ struct vfio_ap_queue { #define VFIO_AP_ISC_INVALID 0xff unsigned char saved_isc; }; -struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q); + +int vfio_ap_mdev_register(void); +void vfio_ap_mdev_unregister(void); +int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q, + unsigned int retry); + #endif /* _VFIO_AP_PRIVATE_H_ */