| Message ID | 1550849400-27152-4-git-send-email-pmorel@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vfio: ap: AP Queue Interrupt Control | expand |
On 2/22/19 10:29 AM, Pierre Morel wrote: > We need to associate the ap_vfio_queue, which will hold the > per queue information for interrupt with a matrix mediated device > which hold the configuration and the way to the CRYCB. > > Let's do this when assigning a APID or a APQI to the mediated device > and clear the relation when unassigning. > > Queuing the devices on a list of free devices and testing the > matrix_mdev pointer to the associated matrix allow us to know > if the queue is associated to the matrix device and associated > or not to a mediated device. > > When resetting an AP queue we must wait until there are no more > messages in the message queue before considering the queue is really > in a clean state. > > Let's do it and wait until the status response code indicate the > queue is empty after issuing a PAPQ/ZAPQ instruction. > > Being at work on the reset function, let's simplify > vfio_ap_mdev_reset_queue and vfio_ap_mdev_reset_queues by using the > vfio_ap_queue structure as parameter. > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > --- > drivers/s390/crypto/vfio_ap_ops.c | 385 +++++++++++++++++++------------------- > 1 file changed, 189 insertions(+), 196 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 900b9cf..172d6eb 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -24,6 +24,57 @@ > #define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough" > #define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device" > > +/** > + * vfio_ap_get_queue: Retrieve a queue with a specific APQN from a list > + * @apqn: The queue APQN > + * > + * Retrieve a queue with a specific APQN from the list of the > + * devices associated with a list. > + * > + * Returns the pointer to the associated vfio_ap_queue > + */ > +struct vfio_ap_queue *vfio_ap_get_queue(int apqn, struct list_head *l) > +{ > + struct vfio_ap_queue *q; > + > + list_for_each_entry(q, l, list) > + if (q->apqn == apqn) > + return q; > + return NULL; > +} > + > +static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q) > +{ > + struct ap_queue_status status; > + int retry = 20; > + > + do { > + status = ap_zapq(q->apqn); > + switch (status.response_code) { > + case AP_RESPONSE_NORMAL: > + while (!status.queue_empty && retry--) { > + msleep(20); > + status = ap_tapq(q->apqn, NULL); > + } I am not sure the above is necessary. I have an email out to the author of the architecture doc to verify. > + if (retry <= 0) > + pr_warn("%s: queue 0x%04x not empty\n", > + __func__, q->apqn); > + return 0; > + case AP_RESPONSE_RESET_IN_PROGRESS: > + case AP_RESPONSE_BUSY: > + msleep(20); > + break; > + default: > + /* things are really broken, give up */ > + pr_warn("%s: zapq error %02x on apqn 0x%04x\n", > + __func__, status.response_code, q->apqn); > + return -EIO; > + } > + } while (retry--); > + > + return -EBUSY; > +} > + > static void vfio_ap_matrix_init(struct ap_config_info *info, > struct ap_matrix *matrix) > { > @@ -45,6 +96,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) > return -ENOMEM; > } > > + INIT_LIST_HEAD(&matrix_mdev->qlist); > vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix); > mdev_set_drvdata(mdev, matrix_mdev); > mutex_lock(&matrix_dev->lock); > @@ -113,162 +165,160 @@ static struct attribute_group *vfio_ap_mdev_type_groups[] = { > NULL, > }; > > -struct vfio_ap_queue_reserved { > - unsigned long *apid; > - unsigned long *apqi; > - bool reserved; > -}; > +static void vfio_ap_free_queue(int apqn, struct ap_matrix_mdev *matrix_mdev) > +{ > + struct vfio_ap_queue *q; > + > + q = vfio_ap_get_queue(apqn, &matrix_mdev->qlist); > + if (!q) > + return; > + q->matrix_mdev = NULL; > + vfio_ap_mdev_reset_queue(q); > + list_move(&q->list, &matrix_dev->free_list); > +} > > /** > - * vfio_ap_has_queue > - * > - * @dev: an AP queue device > - * @data: a struct vfio_ap_queue_reserved reference > - * > - * Flags whether the AP queue device (@dev) has a queue ID containing the APQN, > - * apid or apqi specified in @data: > + * vfio_ap_put_all_domains > * > - * - If @data contains both an apid and apqi value, then @data will be flagged > - * as reserved if the APID and APQI fields for the AP queue device matches > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apid: The apid which associated with all defined APQI of the > + * mediated device will define a AP queue. > * > - * - If @data contains only an apid value, @data will be flagged as > - * reserved if the APID field in the AP queue device matches > - * > - * - If @data contains only an apqi value, @data will be flagged as > - * reserved if the APQI field in the AP queue device matches > - * > - * Returns 0 to indicate the input to function succeeded. Returns -EINVAL if > - * @data does not contain either an apid or apqi. > + * We remove the queue from the list of queues associated with the > + * mediated device and put them back to the free list of the matrix > + * device and clear the matrix_mdev pointer. > */ > -static int vfio_ap_has_queue(struct device *dev, void *data) > +static void vfio_ap_put_all_domains(struct ap_matrix_mdev *matrix_mdev, > + int apid) I would prefer this be named: vfio_ap_mdev_free_queues_with_apid() get/put is typically used to increment/decrement reference counters. What you are doing in this function freeing all queues connected to specified card. > { > - struct vfio_ap_queue_reserved *qres = data; > - struct ap_queue *ap_queue = to_ap_queue(dev); > - ap_qid_t qid; > - unsigned long id; > + int apqi, apqn; > > - if (qres->apid && qres->apqi) { > - qid = AP_MKQID(*qres->apid, *qres->apqi); > - if (qid == ap_queue->qid) > - qres->reserved = true; > - } else if (qres->apid && !qres->apqi) { > - id = AP_QID_CARD(ap_queue->qid); > - if (id == *qres->apid) > - qres->reserved = true; > - } else if (!qres->apid && qres->apqi) { > - id = AP_QID_QUEUE(ap_queue->qid); > - if (id == *qres->apqi) > - qres->reserved = true; > - } else { > - return -EINVAL; > + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { > + apqn = AP_MKQID(apid, apqi); > + vfio_ap_free_queue(apqn, matrix_mdev); > } Maybe you should clear the bit corresponding to apid from the APM here? > - > - return 0; > } > > /** > - * vfio_ap_verify_queue_reserved > - * > - * @matrix_dev: a mediated matrix device > - * @apid: an AP adapter ID > - * @apqi: an AP queue index > - * > - * Verifies that the AP queue with @apid/@apqi is reserved by the VFIO AP device > - * driver according to the following rules: > + * vfio_ap_put_all_cards: > * > - * - If both @apid and @apqi are not NULL, then there must be an AP queue > - * device bound to the vfio_ap driver with the APQN identified by @apid and > - * @apqi > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apqi: The apqi which associated with all defined APID of the > + * mediated device will define a AP queue. > * > - * - If only @apid is not NULL, then there must be an AP queue device bound > - * to the vfio_ap driver with an APQN containing @apid > - * > - * - If only @apqi is not NULL, then there must be an AP queue device bound > - * to the vfio_ap driver with an APQN containing @apqi > - * > - * Returns 0 if the AP queue is reserved; otherwise, returns -EADDRNOTAVAIL. > + * We remove the queue from the list of queues associated with the > + * mediated device and put them back to the free list of the matrix > + * device and clear the matrix_mdev pointer. > */ > -static int vfio_ap_verify_queue_reserved(unsigned long *apid, > - unsigned long *apqi) > +static void vfio_ap_put_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) I don't like this name for the same reasons I stated above for put_all_domains. I prefer something like: vfio_ap_mdev_free_queues_with_apqi() > { > - int ret; > - struct vfio_ap_queue_reserved qres; > + int apid, apqn; > > - qres.apid = apid; > - qres.apqi = apqi; > - qres.reserved = false; > - > - ret = driver_for_each_device(&matrix_dev->vfio_ap_drv->driver, NULL, > - &qres, vfio_ap_has_queue); > - if (ret) > - return ret; > - > - if (qres.reserved) > - return 0; > - > - return -EADDRNOTAVAIL; > + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { > + apqn = AP_MKQID(apid, apqi); > + vfio_ap_free_queue(apqn, matrix_mdev); > + } Maybe clear the apqi from the APM here? > } > > -static int > -vfio_ap_mdev_verify_queues_reserved_for_apid(struct ap_matrix_mdev *matrix_mdev, > - unsigned long apid) > +static void move_and_set(struct list_head *src, struct list_head *dst, > + struct ap_matrix_mdev *matrix_mdev) > { > - int ret; > - unsigned long apqi; > - unsigned long nbits = matrix_mdev->matrix.aqm_max + 1; > - > - if (find_first_bit_inv(matrix_mdev->matrix.aqm, nbits) >= nbits) > - return vfio_ap_verify_queue_reserved(&apid, NULL); > + struct vfio_ap_queue *q, *qtmp; > > - for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, nbits) { > - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); > - if (ret) > - return ret; > + list_for_each_entry_safe(q, qtmp, src, list) { > + list_move(&q->list, dst); > + q->matrix_mdev = matrix_mdev; > } > - > +} > +/** > + * vfio_ap_get_all_domains: > + * > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apqi: The apqi which associated with all defined APID of the > + * mediated device will define a AP queue. > + * > + * We define a local list to put all queues we find on the matrix device > + * free list when associating the apqi with all already defined apid for > + * this matrix mediated device. > + * > + * If we can get all the devices we roll them to the mediated device list > + * If we get errors we unroll them to the free list. > + */ > +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid) I'd prefer to change this name to something like: vfio_ap_mdev_get_queues_with_apid() > +{ > + int apqi, apqn; > + int ret = 0; > + struct vfio_ap_queue *q; > + struct list_head q_list; > + > + INIT_LIST_HEAD(&q_list); > + > + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { > + apqn = AP_MKQID(apid, apqi); > + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); > + if (!q) { > + ret = -EADDRNOTAVAIL; > + goto rewind; > + } > + if (q->matrix_mdev) { > + ret = -EADDRINUSE; > + goto rewind; > + } > + list_move(&q->list, &q_list); IMHO, all of the list moving and rewinding is over complicated and not necessary If you simply maintain the list of queues in the matrix_mdev. > + } > + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); Maybe set the bit for the apid in the APM here instead of in the calling function? > return 0; > +rewind: > + move_and_set(&q_list, &matrix_dev->free_list, NULL); > + return ret; > } > - > /** > - * vfio_ap_mdev_verify_no_sharing > + * vfio_ap_get_all_cards: > * > - * Verifies that the APQNs derived from the cross product of the AP adapter IDs > - * and AP queue indexes comprising the AP matrix are not configured for another > - * mediated device. AP queue sharing is not allowed. > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apqi: The apqi which associated with all defined APID of the > + * mediated device will define a Avfio_ap_put_all_domainsP queue. > * > - * @matrix_mdev: the mediated matrix device > + * We define a local list to put all queues we find on the matrix device > + * free list when associating the apqi with all already defined apid for > + * this matrix mediated device. > * > - * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE. > + * If we can get all the devices we roll them to the mediated device list > + * If we get errors we unroll them to the free list. > */ > -static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev) > +static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) > { I'd prefer to change this name to something like: vfio_ap_mdev_get_queues_with_apqi() > - struct ap_matrix_mdev *lstdev; > - DECLARE_BITMAP(apm, AP_DEVICES); > - DECLARE_BITMAP(aqm, AP_DOMAINS); > - > - list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) { > - if (matrix_mdev == lstdev) > - continue; > - > - memset(apm, 0, sizeof(apm)); > - memset(aqm, 0, sizeof(aqm));vfio_ap_put_all_domains > - > - /* > - * We work on full longs, as we can only exclude the leftover > - * bits in non-inverse order. The leftover is all zeros. > - */ > - if (!bitmap_and(apm, matrix_mdev->matrix.apm, > - lstdev->matrix.apm, AP_DEVICES)) > - continue; > - > - if (!bitmap_and(aqm, matrix_mdev->matrix.aqm, > - lstdev->matrix.aqm, AP_DOMAINS)) > - continue; > - > - return -EADDRINUSE; > + int apid, apqn; > + int ret = 0; > + struct vfio_ap_queue *q; > + struct list_head q_list; > + struct ap_matrix_mdev *tmp = NULL; > +vfio_ap_put_all_domains > + INIT_LIST_HEAD(&q_list); > + > + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { > + apqn = AP_MKQID(apid, apqi); > + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); > + if (!q) { > + ret = -EADDRNOTAVAIL; > + goto rewind; > + } > + if (q->matrix_mdev) { > + ret = -EADDRINUSE; > + goto rewind; > + } > + list_move(&q->list, &q_list); IMHO, all of the list moving and rewinding is over complicated and not necessary if you simply maintain one list of queues in the matrix_mdev. > } > - > + tmp = matrix_mdev; > + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); > return 0; > +rewind: > + move_and_set(&q_list, &matrix_dev->free_list, NULL); > + return ret; > } > > /** > @@ -330,21 +380,15 @@ static ssize_t assign_adapter_store(struct device *dev, > */ > mutex_lock(&matrix_dev->lock); > > - ret = vfio_ap_mdev_verify_queues_reserved_for_apid(matrix_mdev, apid); > + ret = vfio_ap_get_all_domains(matrix_mdev, apid); > if (ret) > goto done; > > set_bit_inv(apid, matrix_mdev->matrix.apm); > > - ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); > - if (ret) > - goto share_err; > - > ret = count; > goto done; > > -share_err: > - clear_bit_inv(apid, matrix_mdev->matrix.apm); > done: > mutex_unlock(&matrix_dev->lock); > > @@ -391,32 +435,13 @@ static ssize_t unassign_adapter_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm); Maybe clear the bit in the vfio_ap_put_all_domains function (which as I said above should be named vfio_ap_mdev_free_queues_for_apid()? > + vfio_ap_put_all_domains(matrix_mdev, apid); > mutex_unlock(&matrix_dev->lock); > > return count; > } > static DEVICE_ATTR_WO(unassign_adapter); > > -static int > -vfio_ap_mdev_verify_queues_reserved_for_apqi(struct ap_matrix_mdev *matrix_mdev, > - unsigned long apqi) > -{ > - int ret; > - unsigned long apid; > - unsigned long nbits = matrix_mdev->matrix.apm_max + 1; > - > - if (find_first_bit_inv(matrix_mdev->matrix.apm, nbits) >= nbits) > - return vfio_ap_verify_queue_reserved(NULL, &apqi); > - > - for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, nbits) { > - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); > - if (ret) > - return ret; > - } > - > - return 0; > -} > - > /** > * assign_domain_store > * > @@ -471,21 +496,15 @@ static ssize_t assign_domain_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > > - ret = vfio_ap_mdev_verify_queues_reserved_for_apqi(matrix_mdev, apqi); > + ret = vfio_ap_get_all_cards(matrix_mdev, apqi); > if (ret) > goto done; > > set_bit_inv(apqi, matrix_mdev->matrix.aqm); > > - ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); > - if (ret) > - goto share_err; > - > ret = count; > goto done; > > -share_err: > - clear_bit_inv(apqi, matrix_mdev->matrix.aqm); > done: > mutex_unlock(&matrix_dev->lock); > > @@ -533,6 +552,7 @@ static ssize_t unassign_domain_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm); Maybe clear the apqi in the vfio_ap_put_all_cards() function (which I suggested should be called vfio_ap_mdev_free_queues_with_apqi()). > + vfio_ap_put_all_cards(matrix_mdev, apqi); > mutex_unlock(&matrix_dev->lock); > > return count; > @@ -790,49 +810,22 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, > return NOTIFY_OK; > } > > -static int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi, > - unsigned int retry) > -{ > - struct ap_queue_status status; > - > - do { > - status = ap_zapq(AP_MKQID(apid, apqi)); > - switch (status.response_code) { > - case AP_RESPONSE_NORMAL: > - return 0; > - case AP_RESPONSE_RESET_IN_PROGRESS: > - case AP_RESPONSE_BUSY: > - msleep(20); > - break; > - default: > - /* things are really broken, give up */ > - return -EIO; > - } > - } while (retry--); > - > - return -EBUSY; > -} > - > static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev) > { > int ret; > int rc = 0; > - unsigned long apid, apqi; > struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); > + struct vfio_ap_queue *q; > > - 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); > - /* > - * Regardless whether a queue turns out to be busy, or > - * is not operational, we need to continue resetting > - * the remaining queues. > - */ > - if (ret) > - rc = ret; > - } > + list_for_each_entry(q, &matrix_mdev->qlist, list) { > + ret = vfio_ap_mdev_reset_queue(q); > + /* > + * Regardless whether a queue turns out to be busy, or > + * is not operational, we need to continue resetting > + * the remaining queues but notice the last error code. > + */ > + if (ret) > + rc = ret; > } > > return rc; >
On 26/02/2019 19:14, Tony Krowiak wrote: > On 2/22/19 10:29 AM, Pierre Morel wrote: >> We need to associate the ap_vfio_queue, which will hold the >> per queue information for interrupt with a matrix mediated device >> which hold the configuration and the way to the CRYCB. >> >> Let's do this when assigning a APID or a APQI to the mediated device >> and clear the relation when unassigning. >> >> Queuing the devices on a list of free devices and testing the >> matrix_mdev pointer to the associated matrix allow us to know >> if the queue is associated to the matrix device and associated >> or not to a mediated device. >> >> When resetting an AP queue we must wait until there are no more >> messages in the message queue before considering the queue is really >> in a clean state. >> >> Let's do it and wait until the status response code indicate the >> queue is empty after issuing a PAPQ/ZAPQ instruction. >> >> Being at work on the reset function, let's simplify >> vfio_ap_mdev_reset_queue and vfio_ap_mdev_reset_queues by using the >> vfio_ap_queue structure as parameter. >> >> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> >> --- >> drivers/s390/crypto/vfio_ap_ops.c | 385 >> +++++++++++++++++++------------------- >> 1 file changed, 189 insertions(+), 196 deletions(-) ...snip... >> +static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q) >> +{ >> + struct ap_queue_status status; >> + int retry = 20; >> + >> + do { >> + status = ap_zapq(q->apqn); >> + switch (status.response_code) { >> + case AP_RESPONSE_NORMAL: >> + while (!status.queue_empty && retry--) { >> + msleep(20); >> + status = ap_tapq(q->apqn, NULL); >> + } > > I am not sure the above is necessary. I have an email out to the author > of the architecture doc to verify. I do not know the question you asked but the documentation is very clear on the reset behavior: a queue is completely reseted only after the RC of reset/zapq is 0 and the queue_empty bit is set. > >> + if (retry <= 0) >> + pr_warn("%s: queue 0x%04x not empty\n", ...snip... >> + * @matrix_mdev: the matrix mediated device for which we want to >> associate >> + * all available queues with a given apqi. >> + * @apid: The apid which associated with all defined APQI of the >> + * mediated device will define a AP queue. >> * >> - * - If @data contains only an apid value, @data will be flagged as >> - * reserved if the APID field in the AP queue device matches >> - * >> - * - If @data contains only an apqi value, @data will be flagged as >> - * reserved if the APQI field in the AP queue device matches >> - * >> - * Returns 0 to indicate the input to function succeeded. Returns >> -EINVAL if >> - * @data does not contain either an apid or apqi. >> + * We remove the queue from the list of queues associated with the >> + * mediated device and put them back to the free list of the matrix >> + * device and clear the matrix_mdev pointer. >> */ >> -static int vfio_ap_has_queue(struct device *dev, void *data) >> +static void vfio_ap_put_all_domains(struct ap_matrix_mdev *matrix_mdev, >> + int apid) > > I would prefer this be named: > > vfio_ap_mdev_free_queues_with_apid() > > get/put is typically used to increment/decrement reference counters. > What you are doing in this function freeing all queues connected to > specified card. OK, I can change this function name and the further one you mentioned. > >> { >> - struct vfio_ap_queue_reserved *qres = data; >> - struct ap_queue *ap_queue = to_ap_queue(dev); >> - ap_qid_t qid; >> - unsigned long id; >> + int apqi, apqn; >> - if (qres->apid && qres->apqi) { >> - qid = AP_MKQID(*qres->apid, *qres->apqi); >> - if (qid == ap_queue->qid) >> - qres->reserved = true; >> - } else if (qres->apid && !qres->apqi) { >> - id = AP_QID_CARD(ap_queue->qid); >> - if (id == *qres->apid) >> - qres->reserved = true; >> - } else if (!qres->apid && qres->apqi) { >> - id = AP_QID_QUEUE(ap_queue->qid); >> - if (id == *qres->apqi) >> - qres->reserved = true; >> - } else { >> - return -EINVAL; >> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { >> + apqn = AP_MKQID(apid, apqi); >> + vfio_ap_free_queue(apqn, matrix_mdev); >> } > > Maybe you should clear the bit corresponding to apid from the APM here? I do not think so, this is pure list handling, the APM bit is already cleared in the unassign_adapter_store function. I only answered once for all comments on naming and bit mask but will treat them the same way. Thanks for comments. Regards, Pierre
On Fri, 22 Feb 2019 16:29:56 +0100 Pierre Morel <pmorel@linux.ibm.com> wrote: > We need to associate the ap_vfio_queue, which will hold the > per queue information for interrupt with a matrix mediated device > which hold the configuration and the way to the CRYCB. > > Let's do this when assigning a APID or a APQI to the mediated device > and clear the relation when unassigning. > > Queuing the devices on a list of free devices and testing the > matrix_mdev pointer to the associated matrix allow us to know > if the queue is associated to the matrix device and associated > or not to a mediated device. > > When resetting an AP queue we must wait until there are no more > messages in the message queue before considering the queue is really > in a clean state. > > Let's do it and wait until the status response code indicate the > queue is empty after issuing a PAPQ/ZAPQ instruction. I'm a bit confused about the context where that list moving etc. is supposed to take place. When are we assigning/deassigning? Is there even supposed to be any activity that we need to zap on the queues? Do we need any serialization/locking on the lists? > > Being at work on the reset function, let's simplify > vfio_ap_mdev_reset_queue and vfio_ap_mdev_reset_queues by using the > vfio_ap_queue structure as parameter. > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > --- > drivers/s390/crypto/vfio_ap_ops.c | 385 +++++++++++++++++++------------------- > 1 file changed, 189 insertions(+), 196 deletions(-)
On 27/02/2019 10:32, Cornelia Huck wrote: > On Fri, 22 Feb 2019 16:29:56 +0100 > Pierre Morel <pmorel@linux.ibm.com> wrote: > >> We need to associate the ap_vfio_queue, which will hold the >> per queue information for interrupt with a matrix mediated device >> which hold the configuration and the way to the CRYCB. >> >> Let's do this when assigning a APID or a APQI to the mediated device >> and clear the relation when unassigning. >> >> Queuing the devices on a list of free devices and testing the >> matrix_mdev pointer to the associated matrix allow us to know >> if the queue is associated to the matrix device and associated >> or not to a mediated device. >> >> When resetting an AP queue we must wait until there are no more >> messages in the message queue before considering the queue is really >> in a clean state. >> >> Let's do it and wait until the status response code indicate the >> queue is empty after issuing a PAPQ/ZAPQ instruction. > > I'm a bit confused about the context where that list moving etc. is > supposed to take place. > > When are we assigning/deassigning? Is there even supposed to be any > activity that we need to zap on the queues? > > Do we need any serialization/locking on the lists? Did I really forget this!? Yes, thanks. Regards, Pierre
On 27/02/2019 10:32, Cornelia Huck wrote: > On Fri, 22 Feb 2019 16:29:56 +0100 > Pierre Morel <pmorel@linux.ibm.com> wrote: > >> We need to associate the ap_vfio_queue, which will hold the >> per queue information for interrupt with a matrix mediated device >> which hold the configuration and the way to the CRYCB. >> >> Let's do this when assigning a APID or a APQI to the mediated device >> and clear the relation when unassigning. >> >> Queuing the devices on a list of free devices and testing the >> matrix_mdev pointer to the associated matrix allow us to know >> if the queue is associated to the matrix device and associated >> or not to a mediated device. >> >> When resetting an AP queue we must wait until there are no more >> messages in the message queue before considering the queue is really >> in a clean state. >> >> Let's do it and wait until the status response code indicate the >> queue is empty after issuing a PAPQ/ZAPQ instruction. > > I'm a bit confused about the context where that list moving etc. is > supposed to take place. You are confused because... it is confuse. > > When are we assigning/deassigning? Is there even supposed to be any > activity that we need to zap on the queues? No I mixed two functionalities here. It is not right. I think I must: - separate the simplification for the reset may be move the chunks to the previous patch as it is a simplification coming with the use of the lists or move them to a separate patch. - make the commit message less confuse :) Regards, Pierre
On 2/27/19 4:29 AM, Pierre Morel wrote: > On 26/02/2019 19:14, Tony Krowiak wrote: >> On 2/22/19 10:29 AM, Pierre Morel wrote: >>> We need to associate the ap_vfio_queue, which will hold the >>> per queue information for interrupt with a matrix mediated device >>> which hold the configuration and the way to the CRYCB. >>> >>> Let's do this when assigning a APID or a APQI to the mediated device >>> and clear the relation when unassigning. >>> >>> Queuing the devices on a list of free devices and testing the >>> matrix_mdev pointer to the associated matrix allow us to know >>> if the queue is associated to the matrix device and associated >>> or not to a mediated device. >>> >>> When resetting an AP queue we must wait until there are no more >>> messages in the message queue before considering the queue is really >>> in a clean state. >>> >>> Let's do it and wait until the status response code indicate the >>> queue is empty after issuing a PAPQ/ZAPQ instruction. >>> >>> Being at work on the reset function, let's simplify >>> vfio_ap_mdev_reset_queue and vfio_ap_mdev_reset_queues by using the >>> vfio_ap_queue structure as parameter. >>> >>> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> >>> --- >>> drivers/s390/crypto/vfio_ap_ops.c | 385 >>> +++++++++++++++++++------------------- >>> 1 file changed, 189 insertions(+), 196 deletions(-) > > ...snip... > >>> +static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q) >>> +{ >>> + struct ap_queue_status status; >>> + int retry = 20; >>> + >>> + do { >>> + status = ap_zapq(q->apqn); >>> + switch (status.response_code) { >>> + case AP_RESPONSE_NORMAL: >>> + while (!status.queue_empty && retry--) { >>> + msleep(20); >>> + status = ap_tapq(q->apqn, NULL); >>> + } >> >> I am not sure the above is necessary. I have an email out to the author >> of the architecture doc to verify. > > I do not know the question you asked but the documentation is very clear > on the reset behavior: a queue is completely reseted only after the RC > of reset/zapq is 0 and the queue_empty bit is set. You may want to check your email once in a while. I copied you on the email I sent to the doc author. What you say is true and you may very well be right, but I found the doc to be confusing in the way it was worded. I would like to get confirmation of the need for this. Notice that I started my sentence off with I AM NOT SURE, so I clearly wasn't saying it is definitely not necessary. > >> >>> + if (retry <= 0) >>> + pr_warn("%s: queue 0x%04x not empty\n", > > ...snip... > >>> + * @matrix_mdev: the matrix mediated device for which we want to >>> associate >>> + * all available queues with a given apqi. >>> + * @apid: The apid which associated with all defined APQI of the >>> + * mediated device will define a AP queue. >>> * >>> - * - If @data contains only an apid value, @data will be flagged as >>> - * reserved if the APID field in the AP queue device matches >>> - * >>> - * - If @data contains only an apqi value, @data will be flagged as >>> - * reserved if the APQI field in the AP queue device matches >>> - * >>> - * Returns 0 to indicate the input to function succeeded. Returns >>> -EINVAL if >>> - * @data does not contain either an apid or apqi. >>> + * We remove the queue from the list of queues associated with the >>> + * mediated device and put them back to the free list of the matrix >>> + * device and clear the matrix_mdev pointer. >>> */ >>> -static int vfio_ap_has_queue(struct device *dev, void *data) >>> +static void vfio_ap_put_all_domains(struct ap_matrix_mdev *matrix_mdev, >>> + int apid) >> >> I would prefer this be named: >> >> vfio_ap_mdev_free_queues_with_apid() >> >> get/put is typically used to increment/decrement reference counters. >> What you are doing in this function freeing all queues connected to >> specified card. > > OK, I can change this function name and the further one you mentioned. > >> >>> { >>> - struct vfio_ap_queue_reserved *qres = data; >>> - struct ap_queue *ap_queue = to_ap_queue(dev); >>> - ap_qid_t qid; >>> - unsigned long id; >>> + int apqi, apqn; >>> - if (qres->apid && qres->apqi) { >>> - qid = AP_MKQID(*qres->apid, *qres->apqi); >>> - if (qid == ap_queue->qid) >>> - qres->reserved = true; >>> - } else if (qres->apid && !qres->apqi) { >>> - id = AP_QID_CARD(ap_queue->qid); >>> - if (id == *qres->apid) >>> - qres->reserved = true; >>> - } else if (!qres->apid && qres->apqi) { >>> - id = AP_QID_QUEUE(ap_queue->qid); >>> - if (id == *qres->apqi) >>> - qres->reserved = true; >>> - } else { >>> - return -EINVAL; >>> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { >>> + apqn = AP_MKQID(apid, apqi); >>> + vfio_ap_free_queue(apqn, matrix_mdev); >>> } >> >> Maybe you should clear the bit corresponding to apid from the APM here? > > I do not think so, this is pure list handling, the APM bit is already > cleared in the unassign_adapter_store function. > > I only answered once for all comments on naming and bit mask but will > treat them the same way. > Thanks for comments. > > Regards, > Pierre > > >
On 2/22/19 10:29 AM, Pierre Morel wrote: > We need to associate the ap_vfio_queue, which will hold the > per queue information for interrupt with a matrix mediated device > which hold the configuration and the way to the CRYCB. > > Let's do this when assigning a APID or a APQI to the mediated device > and clear the relation when unassigning. > > Queuing the devices on a list of free devices and testing the > matrix_mdev pointer to the associated matrix allow us to know > if the queue is associated to the matrix device and associated > or not to a mediated device. > > When resetting an AP queue we must wait until there are no more > messages in the message queue before considering the queue is really > in a clean state. > > Let's do it and wait until the status response code indicate the > queue is empty after issuing a PAPQ/ZAPQ instruction. > > Being at work on the reset function, let's simplify > vfio_ap_mdev_reset_queue and vfio_ap_mdev_reset_queues by using the > vfio_ap_queue structure as parameter. > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > --- > drivers/s390/crypto/vfio_ap_ops.c | 385 +++++++++++++++++++------------------- > 1 file changed, 189 insertions(+), 196 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 900b9cf..172d6eb 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -24,6 +24,57 @@ > #define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough" > #define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device" > > +/** > + * vfio_ap_get_queue: Retrieve a queue with a specific APQN from a list > + * @apqn: The queue APQN > + * > + * Retrieve a queue with a specific APQN from the list of the > + * devices associated with a list. > + * > + * Returns the pointer to the associated vfio_ap_queue > + */ > +struct vfio_ap_queue *vfio_ap_get_queue(int apqn, struct list_head *l) > +{ > + struct vfio_ap_queue *q; > + > + list_for_each_entry(q, l, list) > + if (q->apqn == apqn) > + return q; > + return NULL; > +} I think you can simplify this patch as well as save a number of LOCs by going restoring your previous version of this function that used the driver_find_device() function to retrieve the queue with a specific APQN. Please see the rest of my comments for further clarification. > + > +static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q) > +{ > + struct ap_queue_status status; > + int retry = 20; > + > + do { > + status = ap_zapq(q->apqn); > + switch (status.response_code) { > + case AP_RESPONSE_NORMAL: > + while (!status.queue_empty && retry--) { > + msleep(20); > + status = ap_tapq(q->apqn, NULL); > + } > + if (retry <= 0) > + pr_warn("%s: queue 0x%04x not empty\n", > + __func__, q->apqn); > + return 0; > + case AP_RESPONSE_RESET_IN_PROGRESS: > + case AP_RESPONSE_BUSY: > + msleep(20); > + break; > + default: > + /* things are really broken, give up */ > + pr_warn("%s: zapq error %02x on apqn 0x%04x\n", > + __func__, status.response_code, q->apqn); > + return -EIO; > + } > + } while (retry--); > + > + return -EBUSY; > +} > + > static void vfio_ap_matrix_init(struct ap_config_info *info, > struct ap_matrix *matrix) > { > @@ -45,6 +96,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) > return -ENOMEM; > } > > + INIT_LIST_HEAD(&matrix_mdev->qlist); > vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix); > mdev_set_drvdata(mdev, matrix_mdev); > mutex_lock(&matrix_dev->lock); > @@ -113,162 +165,160 @@ static struct attribute_group *vfio_ap_mdev_type_groups[] = { > NULL, > }; > > -struct vfio_ap_queue_reserved { > - unsigned long *apid; > - unsigned long *apqi; > - bool reserved; > -}; > +static void vfio_ap_free_queue(int apqn, struct ap_matrix_mdev *matrix_mdev) > +{ > + struct vfio_ap_queue *q; > + > + q = vfio_ap_get_queue(apqn, &matrix_mdev->qlist); If you restore the previous version of vfio_ap_get_queue(), we don't need the qlist to retrieve the q. The apqn is sufficient. > + if (!q) > + return; > + q->matrix_mdev = NULL; > + vfio_ap_mdev_reset_queue(q); > + list_move(&q->list, &matrix_dev->free_list); If we get rid of the qlist and free_list, then we don't need the list_move function. > +} > > /** > - * vfio_ap_has_queue > - * > - * @dev: an AP queue device > - * @data: a struct vfio_ap_queue_reserved reference > - * > - * Flags whether the AP queue device (@dev) has a queue ID containing the APQN, > - * apid or apqi specified in @data: > + * vfio_ap_put_all_domains: > * > - * - If @data contains both an apid and apqi value, then @data will be flagged > - * as reserved if the APID and APQI fields for the AP queue device matches > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apid: The apid which associated with all defined APQI of the > + * mediated device will define a AP queue. > * > - * - If @data contains only an apid value, @data will be flagged as > - * reserved if the APID field in the AP queue device matches > - * > - * - If @data contains only an apqi value, @data will be flagged as > - * reserved if the APQI field in the AP queue device matches > - * > - * Returns 0 to indicate the input to function succeeded. Returns -EINVAL if > - * @data does not contain either an apid or apqi. > + * We remove the queue from the list of queues associated with the > + * mediated device and put them back to the free list of the matrix > + * device and clear the matrix_mdev pointer. > */ > -static int vfio_ap_has_queue(struct device *dev, void *data) > +static void vfio_ap_put_all_domains(struct ap_matrix_mdev *matrix_mdev, > + int apid) > { > - struct vfio_ap_queue_reserved *qres = data; > - struct ap_queue *ap_queue = to_ap_queue(dev); > - ap_qid_t qid; > - unsigned long id; > + int apqi, apqn; > > - if (qres->apid && qres->apqi) { > - qid = AP_MKQID(*qres->apid, *qres->apqi); > - if (qid == ap_queue->qid) > - qres->reserved = true; > - } else if (qres->apid && !qres->apqi) { > - id = AP_QID_CARD(ap_queue->qid); > - if (id == *qres->apid) > - qres->reserved = true; > - } else if (!qres->apid && qres->apqi) { > - id = AP_QID_QUEUE(ap_queue->qid); > - if (id == *qres->apqi) > - qres->reserved = true; > - } else { > - return -EINVAL; > + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { > + apqn = AP_MKQID(apid, apqi); > + vfio_ap_free_queue(apqn, matrix_mdev); > } > - > - return 0; > } > > /** > - * vfio_ap_verify_queue_reserved > - * > - * @matrix_dev: a mediated matrix device > - * @apid: an AP adapter ID > - * @apqi: an AP queue index > - * > - * Verifies that the AP queue with @apid/@apqi is reserved by the VFIO AP device > - * driver according to the following rules: > + * vfio_ap_put_all_cards: > * > - * - If both @apid and @apqi are not NULL, then there must be an AP queue > - * device bound to the vfio_ap driver with the APQN identified by @apid and > - * @apqi > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apqi: The apqi which associated with all defined APID of the > + * mediated device will define a AP queue. > * > - * - If only @apid is not NULL, then there must be an AP queue device bound > - * to the vfio_ap driver with an APQN containing @apid > - * > - * - If only @apqi is not NULL, then there must be an AP queue device bound > - * to the vfio_ap driver with an APQN containing @apqi > - * > - * Returns 0 if the AP queue is reserved; otherwise, returns -EADDRNOTAVAIL. > + * We remove the queue from the list of queues associated with the > + * mediated device and put them back to the free list of the matrix > + * device and clear the matrix_mdev pointer. > */ > -static int vfio_ap_verify_queue_reserved(unsigned long *apid, > - unsigned long *apqi) > +static void vfio_ap_put_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) > { > - int ret; > - struct vfio_ap_queue_reserved qres; > + int apid, apqn; > > - qres.apid = apid; > - qres.apqi = apqi; > - qres.reserved = false; > - > - ret = driver_for_each_device(&matrix_dev->vfio_ap_drv->driver, NULL, > - &qres, vfio_ap_has_queue); > - if (ret) > - return ret; > - > - if (qres.reserved) > - return 0; > - > - return -EADDRNOTAVAIL; > + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { > + apqn = AP_MKQID(apid, apqi); > + vfio_ap_free_queue(apqn, matrix_mdev); > + } > } > > -static int > -vfio_ap_mdev_verify_queues_reserved_for_apid(struct ap_matrix_mdev *matrix_mdev, > - unsigned long apid) > +static void move_and_set(struct list_head *src, struct list_head *dst, > + struct ap_matrix_mdev *matrix_mdev) > { > - int ret; > - unsigned long apqi; > - unsigned long nbits = matrix_mdev->matrix.aqm_max + 1; > - > - if (find_first_bit_inv(matrix_mdev->matrix.aqm, nbits) >= nbits) > - return vfio_ap_verify_queue_reserved(&apid, NULL); > + struct vfio_ap_queue *q, *qtmp; > > - for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, nbits) { > - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); > - if (ret) > - return ret; > + list_for_each_entry_safe(q, qtmp, src, list) { > + list_move(&q->list, dst); > + q->matrix_mdev = matrix_mdev; > } If we get rid of the lists, this function becomes unnecessary. > - > +} > +/** > + * vfio_ap_get_all_domains: > + * > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apqi: The apqi which associated with all defined APID of the > + * mediated device will define a AP queue. > + * > + * We define a local list to put all queues we find on the matrix device > + * free list when associating the apqi with all already defined apid for > + * this matrix mediated device. > + * > + * If we can get all the devices we roll them to the mediated device list > + * If we get errors we unroll them to the free list. > + */ > +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid) > +{ > + int apqi, apqn; > + int ret = 0; > + struct vfio_ap_queue *q; > + struct list_head q_list; > + > + INIT_LIST_HEAD(&q_list); > + > + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { > + apqn = AP_MKQID(apid, apqi); > + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); > + if (!q) { > + ret = -EADDRNOTAVAIL; > + goto rewind; If we get rid of the lists, there is no need to rewind > + } > + if (q->matrix_mdev) { > + ret = -EADDRINUSE; > + goto rewind; If we get rid of the lists, there is no need to rewind > + } > + list_move(&q->list, &q_list); If we get rid of the lists, there is no need to move the queue to q_list. > + } > + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); If we get rid of the lists, this call becomes unnecessary. > return 0; > +rewind: > + move_and_set(&q_list, &matrix_dev->free_list, NULL); If we get rid of the lists, this call becomes unnecessary. > + return ret; > } > - > /** > - * vfio_ap_mdev_verify_no_sharing > + * vfio_ap_get_all_cards: > * > - * Verifies that the APQNs derived from the cross product of the AP adapter IDs > - * and AP queue indexes comprising the AP matrix are not configured for another > - * mediated device. AP queue sharing is not allowed. > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apqi: The apqi which associated with all defined APID of the > + * mediated device will define a AP queue. > * > - * @matrix_mdev: the mediated matrix device > + * We define a local list to put all queues we find on the matrix device > + * free list when associating the apqi with all already defined apid for > + * this matrix mediated device. > * > - * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE. > + * If we can get all the devices we roll them to the mediated device list > + * If we get errors we unroll them to the free list. > */ > -static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev) > +static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) > { > - struct ap_matrix_mdev *lstdev; > - DECLARE_BITMAP(apm, AP_DEVICES); > - DECLARE_BITMAP(aqm, AP_DOMAINS); > - > - list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) { > - if (matrix_mdev == lstdev) > - continue; > - > - memset(apm, 0, sizeof(apm)); > - memset(aqm, 0, sizeof(aqm)); > - > - /* > - * We work on full longs, as we can only exclude the leftover > - * bits in non-inverse order. The leftover is all zeros. > - */ > - if (!bitmap_and(apm, matrix_mdev->matrix.apm, > - lstdev->matrix.apm, AP_DEVICES)) > - continue; > - > - if (!bitmap_and(aqm, matrix_mdev->matrix.aqm, > - lstdev->matrix.aqm, AP_DOMAINS)) > - continue; > - > - return -EADDRINUSE; > + int apid, apqn; > + int ret = 0; > + struct vfio_ap_queue *q; > + struct list_head q_list; > + struct ap_matrix_mdev *tmp = NULL; > + > + INIT_LIST_HEAD(&q_list); > + > + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { > + apqn = AP_MKQID(apid, apqi); > + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); > + if (!q) { > + ret = -EADDRNOTAVAIL; > + goto rewind; No lists, no rewind necessary > + } > + if (q->matrix_mdev) { > + ret = -EADDRINUSE; > + goto rewind; No lists, no rewind necessary > + } > + list_move(&q->list, &q_list); No lists, no need to move the queue to q_list > } > - > + tmp = matrix_mdev; > + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); No lists, no need to move and set. > return 0; > +rewind: > + move_and_set(&q_list, &matrix_dev->free_list, NULL); No lists, no need to move and set. > + return ret; > } > > /** > @@ -330,21 +380,15 @@ static ssize_t assign_adapter_store(struct device *dev, > */ > mutex_lock(&matrix_dev->lock); > > - ret = vfio_ap_mdev_verify_queues_reserved_for_apid(matrix_mdev, apid); > + ret = vfio_ap_get_all_domains(matrix_mdev, apid); > if (ret) > goto done; > > set_bit_inv(apid, matrix_mdev->matrix.apm); > > - ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); > - if (ret) > - goto share_err; > - > ret = count; > goto done; > > -share_err: > - clear_bit_inv(apid, matrix_mdev->matrix.apm); > done: > mutex_unlock(&matrix_dev->lock); > > @@ -391,32 +435,13 @@ static ssize_t unassign_adapter_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm); > + vfio_ap_put_all_domains(matrix_mdev, apid); > mutex_unlock(&matrix_dev->lock); > > return count; > } > static DEVICE_ATTR_WO(unassign_adapter); > > -static int > -vfio_ap_mdev_verify_queues_reserved_for_apqi(struct ap_matrix_mdev *matrix_mdev, > - unsigned long apqi) > -{ > - int ret; > - unsigned long apid; > - unsigned long nbits = matrix_mdev->matrix.apm_max + 1; > - > - if (find_first_bit_inv(matrix_mdev->matrix.apm, nbits) >= nbits) > - return vfio_ap_verify_queue_reserved(NULL, &apqi); > - > - for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, nbits) { > - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); > - if (ret) > - return ret; > - } > - > - return 0; > -} > - > /** > * assign_domain_store > * > @@ -471,21 +496,15 @@ static ssize_t assign_domain_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > > - ret = vfio_ap_mdev_verify_queues_reserved_for_apqi(matrix_mdev, apqi); > + ret = vfio_ap_get_all_cards(matrix_mdev, apqi); > if (ret) > goto done; > > set_bit_inv(apqi, matrix_mdev->matrix.aqm); > > - ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); > - if (ret) > - goto share_err; > - > ret = count; > goto done; > > -share_err: > - clear_bit_inv(apqi, matrix_mdev->matrix.aqm); > done: > mutex_unlock(&matrix_dev->lock); > > @@ -533,6 +552,7 @@ static ssize_t unassign_domain_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm); > + vfio_ap_put_all_cards(matrix_mdev, apqi); > mutex_unlock(&matrix_dev->lock); > > return count; > @@ -790,49 +810,22 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, > return NOTIFY_OK; > } > > -static int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi, > - unsigned int retry) > -{ > - struct ap_queue_status status; > - > - do { > - status = ap_zapq(AP_MKQID(apid, apqi)); > - switch (status.response_code) { > - case AP_RESPONSE_NORMAL: > - return 0; > - case AP_RESPONSE_RESET_IN_PROGRESS: > - case AP_RESPONSE_BUSY: > - msleep(20); > - break; > - default: > - /* things are really broken, give up */ > - return -EIO; > - } > - } while (retry--); > - > - return -EBUSY; > -} > - > static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev) > { > int ret; > int rc = 0; > - unsigned long apid, apqi; > struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); > + struct vfio_ap_queue *q; > > - 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); > - /* > - * Regardless whether a queue turns out to be busy, or > - * is not operational, we need to continue resetting > - * the remaining queues. > - */ > - if (ret) > - rc = ret; > - } > + list_for_each_entry(q, &matrix_mdev->qlist, list) { > + ret = vfio_ap_mdev_reset_queue(q); > + /* > + * Regardless whether a queue turns out to be busy, or > + * is not operational, we need to continue resetting > + * the remaining queues but notice the last error code. > + */ > + if (ret) > + rc = ret; > } There is no need for this change. Without the lists, we can keep the code as-is above. Having the list buys us absolutely nothing here. > > return rc; >
On Fri, 22 Feb 2019 16:29:56 +0100 Pierre Morel <pmorel@linux.ibm.com> wrote: > We need to associate the ap_vfio_queue, which will hold the > per queue information for interrupt with a matrix mediated device > which hold the configuration and the way to the CRYCB. [..] > +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid) > +{ > + int apqi, apqn; > + int ret = 0; > + struct vfio_ap_queue *q; > + struct list_head q_list; > + > + INIT_LIST_HEAD(&q_list); > + > + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { > + apqn = AP_MKQID(apid, apqi); > + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); > + if (!q) { > + ret = -EADDRNOTAVAIL; > + goto rewind; > + } > + if (q->matrix_mdev) { > + ret = -EADDRINUSE; You tried to get the q from matrix_dev->free_list thus modulo races q->matrix_mdev should be 0. This change breaks the error codes in a sense that it becomes impossible to provoke EADDRINUSE (the proper error code for taken by another matrix_mdev). > + goto rewind; > + } > + list_move(&q->list, &q_list); > + } > + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); > return 0; > +rewind: > + move_and_set(&q_list, &matrix_dev->free_list, NULL); > + return ret; > } > - > /** > - * vfio_ap_mdev_verify_no_sharing > + * vfio_ap_get_all_cards: > * > - * Verifies that the APQNs derived from the cross product of the AP adapter IDs > - * and AP queue indexes comprising the AP matrix are not configured for another > - * mediated device. AP queue sharing is not allowed. > + * @matrix_mdev: the matrix mediated device for which we want to associate > + * all available queues with a given apqi. > + * @apqi: The apqi which associated with all defined APID of the > + * mediated device will define a AP queue. > * > - * @matrix_mdev: the mediated matrix device > + * We define a local list to put all queues we find on the matrix device > + * free list when associating the apqi with all already defined apid for > + * this matrix mediated device. > * > - * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE. > + * If we can get all the devices we roll them to the mediated device list > + * If we get errors we unroll them to the free list. > */ > -static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev) > +static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) > { > - struct ap_matrix_mdev *lstdev; > - DECLARE_BITMAP(apm, AP_DEVICES); > - DECLARE_BITMAP(aqm, AP_DOMAINS); > - > - list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) { > - if (matrix_mdev == lstdev) > - continue; > - > - memset(apm, 0, sizeof(apm)); > - memset(aqm, 0, sizeof(aqm)); > - > - /* > - * We work on full longs, as we can only exclude the leftover > - * bits in non-inverse order. The leftover is all zeros. > - */ > - if (!bitmap_and(apm, matrix_mdev->matrix.apm, > - lstdev->matrix.apm, AP_DEVICES)) > - continue; > - > - if (!bitmap_and(aqm, matrix_mdev->matrix.aqm, > - lstdev->matrix.aqm, AP_DOMAINS)) > - continue; > - > - return -EADDRINUSE; > + int apid, apqn; > + int ret = 0; > + struct vfio_ap_queue *q; > + struct list_head q_list; > + struct ap_matrix_mdev *tmp = NULL; > + > + INIT_LIST_HEAD(&q_list); > + > + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { > + apqn = AP_MKQID(apid, apqi); > + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); > + if (!q) { > + ret = -EADDRNOTAVAIL; > + goto rewind; > + } > + if (q->matrix_mdev) { > + ret = -EADDRINUSE; Same here! Regards, Halil > + goto rewind; > + } > + list_move(&q->list, &q_list); > } [..]
On 04/03/2019 03:09, Halil Pasic wrote: > On Fri, 22 Feb 2019 16:29:56 +0100 > Pierre Morel <pmorel@linux.ibm.com> wrote: > >> We need to associate the ap_vfio_queue, which will hold the >> per queue information for interrupt with a matrix mediated device >> which hold the configuration and the way to the CRYCB. > [..] >> +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid) >> +{ >> + int apqi, apqn; >> + int ret = 0; >> + struct vfio_ap_queue *q; >> + struct list_head q_list; >> + >> + INIT_LIST_HEAD(&q_list); >> + >> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { >> + apqn = AP_MKQID(apid, apqi); >> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); >> + if (!q) { >> + ret = -EADDRNOTAVAIL; >> + goto rewind; >> + } >> + if (q->matrix_mdev) { >> + ret = -EADDRINUSE; > > You tried to get the q from matrix_dev->free_list thus modulo races > q->matrix_mdev should be 0. This change breaks the error codes in a > sense that it becomes impossible to provoke EADDRINUSE (the proper > error code for taken by another matrix_mdev). > right. I will change this. Regards, Pierre
On 3/3/19 9:09 PM, Halil Pasic wrote: > On Fri, 22 Feb 2019 16:29:56 +0100 > Pierre Morel <pmorel@linux.ibm.com> wrote: > >> We need to associate the ap_vfio_queue, which will hold the >> per queue information for interrupt with a matrix mediated device >> which hold the configuration and the way to the CRYCB. > [..] >> +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid) >> +{ >> + int apqi, apqn; >> + int ret = 0; >> + struct vfio_ap_queue *q; >> + struct list_head q_list; >> + >> + INIT_LIST_HEAD(&q_list); >> + >> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { >> + apqn = AP_MKQID(apid, apqi); >> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); >> + if (!q) { >> + ret = -EADDRNOTAVAIL; >> + goto rewind; >> + } >> + if (q->matrix_mdev) { >> + ret = -EADDRINUSE; > > You tried to get the q from matrix_dev->free_list thus modulo races > q->matrix_mdev should be 0. This change breaks the error codes in a > sense that it becomes impossible to provoke EADDRINUSE (the proper > error code for taken by another matrix_mdev). I don't understand what you are saying here. AFIU, the idea here is to pull the q from the free list. If there is no q for the apqn on the free list, then that would indicate the queue has not been bound to a driver in which case the appropriate rc is EADDRNOTAVAIL. If the queue has been bound, then a check is done to see whether the queue has been associated with an mdev device. If so, the rc is -EADDRINUSE, which is also appropriate. What am I missing? > >> + goto rewind; >> + } >> + list_move(&q->list, &q_list); >> + } >> + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); >> return 0; >> +rewind: >> + move_and_set(&q_list, &matrix_dev->free_list, NULL); >> + return ret; >> } >> - >> /** >> - * vfio_ap_mdev_verify_no_sharing >> + * vfio_ap_get_all_cards: >> * >> - * Verifies that the APQNs derived from the cross product of the AP adapter IDs >> - * and AP queue indexes comprising the AP matrix are not configured for another >> - * mediated device. AP queue sharing is not allowed. >> + * @matrix_mdev: the matrix mediated device for which we want to associate >> + * all available queues with a given apqi. >> + * @apqi: The apqi which associated with all defined APID of the >> + * mediated device will define a AP queue. >> * >> - * @matrix_mdev: the mediated matrix device >> + * We define a local list to put all queues we find on the matrix device >> + * free list when associating the apqi with all already defined apid for >> + * this matrix mediated device. >> * >> - * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE. >> + * If we can get all the devices we roll them to the mediated device list >> + * If we get errors we unroll them to the free list. >> */ >> -static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev) >> +static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) >> { >> - struct ap_matrix_mdev *lstdev; >> - DECLARE_BITMAP(apm, AP_DEVICES); >> - DECLARE_BITMAP(aqm, AP_DOMAINS); >> - >> - list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) { >> - if (matrix_mdev == lstdev) >> - continue; >> - >> - memset(apm, 0, sizeof(apm)); >> - memset(aqm, 0, sizeof(aqm)); >> - >> - /* >> - * We work on full longs, as we can only exclude the leftover >> - * bits in non-inverse order. The leftover is all zeros. >> - */ >> - if (!bitmap_and(apm, matrix_mdev->matrix.apm, >> - lstdev->matrix.apm, AP_DEVICES)) >> - continue; >> - >> - if (!bitmap_and(aqm, matrix_mdev->matrix.aqm, >> - lstdev->matrix.aqm, AP_DOMAINS)) >> - continue; >> - >> - return -EADDRINUSE; >> + int apid, apqn; >> + int ret = 0; >> + struct vfio_ap_queue *q; >> + struct list_head q_list; >> + struct ap_matrix_mdev *tmp = NULL; >> + >> + INIT_LIST_HEAD(&q_list); >> + >> + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { >> + apqn = AP_MKQID(apid, apqi); >> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); >> + if (!q) { >> + ret = -EADDRNOTAVAIL; >> + goto rewind; >> + } >> + if (q->matrix_mdev) { >> + ret = -EADDRINUSE; > > Same here! > > Regards, > Halil > >> + goto rewind; >> + } >> + list_move(&q->list, &q_list); >> } > > [..] >
On 3/3/19 9:09 PM, Halil Pasic wrote: > On Fri, 22 Feb 2019 16:29:56 +0100 > Pierre Morel <pmorel@linux.ibm.com> wrote: > >> We need to associate the ap_vfio_queue, which will hold the >> per queue information for interrupt with a matrix mediated device >> which hold the configuration and the way to the CRYCB. > [..] >> +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid) >> +{ >> + int apqi, apqn; >> + int ret = 0; >> + struct vfio_ap_queue *q; >> + struct list_head q_list; >> + >> + INIT_LIST_HEAD(&q_list); >> + >> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { >> + apqn = AP_MKQID(apid, apqi); >> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); >> + if (!q) { >> + ret = -EADDRNOTAVAIL; >> + goto rewind; >> + } >> + if (q->matrix_mdev) { >> + ret = -EADDRINUSE; > > You tried to get the q from matrix_dev->free_list thus modulo races > q->matrix_mdev should be 0. This change breaks the error codes in a > sense that it becomes impossible to provoke EADDRINUSE (the proper > error code for taken by another matrix_mdev). It is necessary to determine if the queue is in use by another mdev, so it will still be necessary to traverse all of the matrix_mdev structs to see if q is in matrix_mdev->qlist. It seems that maintaining the qlist does not buy us much. > >> + goto rewind; >> + } >> + list_move(&q->list, &q_list); >> + } >> + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); >> return 0; >> +rewind: >> + move_and_set(&q_list, &matrix_dev->free_list, NULL); >> + return ret; >> } >> - >> /** >> - * vfio_ap_mdev_verify_no_sharing >> + * vfio_ap_get_all_cards: >> * >> - * Verifies that the APQNs derived from the cross product of the AP adapter IDs >> - * and AP queue indexes comprising the AP matrix are not configured for another >> - * mediated device. AP queue sharing is not allowed. >> + * @matrix_mdev: the matrix mediated device for which we want to associate >> + * all available queues with a given apqi. >> + * @apqi: The apqi which associated with all defined APID of the >> + * mediated device will define a AP queue. >> * >> - * @matrix_mdev: the mediated matrix device >> + * We define a local list to put all queues we find on the matrix device >> + * free list when associating the apqi with all already defined apid for >> + * this matrix mediated device. >> * >> - * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE. >> + * If we can get all the devices we roll them to the mediated device list >> + * If we get errors we unroll them to the free list. >> */ >> -static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev) >> +static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) >> { >> - struct ap_matrix_mdev *lstdev; >> - DECLARE_BITMAP(apm, AP_DEVICES); >> - DECLARE_BITMAP(aqm, AP_DOMAINS); >> - >> - list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) { >> - if (matrix_mdev == lstdev) >> - continue; >> - >> - memset(apm, 0, sizeof(apm)); >> - memset(aqm, 0, sizeof(aqm)); >> - >> - /* >> - * We work on full longs, as we can only exclude the leftover >> - * bits in non-inverse order. The leftover is all zeros. >> - */ >> - if (!bitmap_and(apm, matrix_mdev->matrix.apm, >> - lstdev->matrix.apm, AP_DEVICES)) >> - continue; >> - >> - if (!bitmap_and(aqm, matrix_mdev->matrix.aqm, >> - lstdev->matrix.aqm, AP_DOMAINS)) >> - continue; >> - >> - return -EADDRINUSE; >> + int apid, apqn; >> + int ret = 0; >> + struct vfio_ap_queue *q; >> + struct list_head q_list; >> + struct ap_matrix_mdev *tmp = NULL; >> + >> + INIT_LIST_HEAD(&q_list); >> + >> + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { >> + apqn = AP_MKQID(apid, apqi); >> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); >> + if (!q) { >> + ret = -EADDRNOTAVAIL; >> + goto rewind; >> + } >> + if (q->matrix_mdev) { >> + ret = -EADDRINUSE; > > Same here! > > Regards, > Halil > >> + goto rewind; >> + } >> + list_move(&q->list, &q_list); >> } > > [..] >
On 12/03/2019 22:39, Tony Krowiak wrote: > On 3/3/19 9:09 PM, Halil Pasic wrote: >> On Fri, 22 Feb 2019 16:29:56 +0100 >> Pierre Morel <pmorel@linux.ibm.com> wrote: >> >>> We need to associate the ap_vfio_queue, which will hold the >>> per queue information for interrupt with a matrix mediated device >>> which hold the configuration and the way to the CRYCB. >> [..] >>> +static int vfio_ap_get_all_domains(struct ap_matrix_mdev >>> *matrix_mdev, int apid) >>> +{ >>> + int apqi, apqn; >>> + int ret = 0; >>> + struct vfio_ap_queue *q; >>> + struct list_head q_list; >>> + >>> + INIT_LIST_HEAD(&q_list); >>> + >>> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { >>> + apqn = AP_MKQID(apid, apqi); >>> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); >>> + if (!q) { >>> + ret = -EADDRNOTAVAIL; >>> + goto rewind; >>> + } >>> + if (q->matrix_mdev) { >>> + ret = -EADDRINUSE; >> >> You tried to get the q from matrix_dev->free_list thus modulo races >> q->matrix_mdev should be 0. This change breaks the error codes in a >> sense that it becomes impossible to provoke EADDRINUSE (the proper >> error code for taken by another matrix_mdev). > > It is necessary to determine if the queue is in use by another mdev, so > it will still be necessary to traverse all of the matrix_mdev structs to > see if q is in matrix_mdev->qlist. It seems that maintaining the qlist > does not buy us much. > Tony, Halil already pointed out this issue and I already answered. Please, no need to duplicate the remarks. Pierre
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index 900b9cf..172d6eb 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -24,6 +24,57 @@ #define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough" #define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device" +/** + * vfio_ap_get_queue: Retrieve a queue with a specific APQN from a list + * @apqn: The queue APQN + * + * Retrieve a queue with a specific APQN from the list of the + * devices associated with a list. + * + * Returns the pointer to the associated vfio_ap_queue + */ +struct vfio_ap_queue *vfio_ap_get_queue(int apqn, struct list_head *l) +{ + struct vfio_ap_queue *q; + + list_for_each_entry(q, l, list) + if (q->apqn == apqn) + return q; + return NULL; +} + +static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q) +{ + struct ap_queue_status status; + int retry = 20; + + do { + status = ap_zapq(q->apqn); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + while (!status.queue_empty && retry--) { + msleep(20); + status = ap_tapq(q->apqn, NULL); + } + if (retry <= 0) + pr_warn("%s: queue 0x%04x not empty\n", + __func__, q->apqn); + return 0; + case AP_RESPONSE_RESET_IN_PROGRESS: + case AP_RESPONSE_BUSY: + msleep(20); + break; + default: + /* things are really broken, give up */ + pr_warn("%s: zapq error %02x on apqn 0x%04x\n", + __func__, status.response_code, q->apqn); + return -EIO; + } + } while (retry--); + + return -EBUSY; +} + static void vfio_ap_matrix_init(struct ap_config_info *info, struct ap_matrix *matrix) { @@ -45,6 +96,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) return -ENOMEM; } + INIT_LIST_HEAD(&matrix_mdev->qlist); vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix); mdev_set_drvdata(mdev, matrix_mdev); mutex_lock(&matrix_dev->lock); @@ -113,162 +165,160 @@ static struct attribute_group *vfio_ap_mdev_type_groups[] = { NULL, }; -struct vfio_ap_queue_reserved { - unsigned long *apid; - unsigned long *apqi; - bool reserved; -}; +static void vfio_ap_free_queue(int apqn, struct ap_matrix_mdev *matrix_mdev) +{ + struct vfio_ap_queue *q; + + q = vfio_ap_get_queue(apqn, &matrix_mdev->qlist); + if (!q) + return; + q->matrix_mdev = NULL; + vfio_ap_mdev_reset_queue(q); + list_move(&q->list, &matrix_dev->free_list); +} /** - * vfio_ap_has_queue - * - * @dev: an AP queue device - * @data: a struct vfio_ap_queue_reserved reference - * - * Flags whether the AP queue device (@dev) has a queue ID containing the APQN, - * apid or apqi specified in @data: + * vfio_ap_put_all_domains: * - * - If @data contains both an apid and apqi value, then @data will be flagged - * as reserved if the APID and APQI fields for the AP queue device matches + * @matrix_mdev: the matrix mediated device for which we want to associate + * all available queues with a given apqi. + * @apid: The apid which associated with all defined APQI of the + * mediated device will define a AP queue. * - * - If @data contains only an apid value, @data will be flagged as - * reserved if the APID field in the AP queue device matches - * - * - If @data contains only an apqi value, @data will be flagged as - * reserved if the APQI field in the AP queue device matches - * - * Returns 0 to indicate the input to function succeeded. Returns -EINVAL if - * @data does not contain either an apid or apqi. + * We remove the queue from the list of queues associated with the + * mediated device and put them back to the free list of the matrix + * device and clear the matrix_mdev pointer. */ -static int vfio_ap_has_queue(struct device *dev, void *data) +static void vfio_ap_put_all_domains(struct ap_matrix_mdev *matrix_mdev, + int apid) { - struct vfio_ap_queue_reserved *qres = data; - struct ap_queue *ap_queue = to_ap_queue(dev); - ap_qid_t qid; - unsigned long id; + int apqi, apqn; - if (qres->apid && qres->apqi) { - qid = AP_MKQID(*qres->apid, *qres->apqi); - if (qid == ap_queue->qid) - qres->reserved = true; - } else if (qres->apid && !qres->apqi) { - id = AP_QID_CARD(ap_queue->qid); - if (id == *qres->apid) - qres->reserved = true; - } else if (!qres->apid && qres->apqi) { - id = AP_QID_QUEUE(ap_queue->qid); - if (id == *qres->apqi) - qres->reserved = true; - } else { - return -EINVAL; + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { + apqn = AP_MKQID(apid, apqi); + vfio_ap_free_queue(apqn, matrix_mdev); } - - return 0; } /** - * vfio_ap_verify_queue_reserved - * - * @matrix_dev: a mediated matrix device - * @apid: an AP adapter ID - * @apqi: an AP queue index - * - * Verifies that the AP queue with @apid/@apqi is reserved by the VFIO AP device - * driver according to the following rules: + * vfio_ap_put_all_cards: * - * - If both @apid and @apqi are not NULL, then there must be an AP queue - * device bound to the vfio_ap driver with the APQN identified by @apid and - * @apqi + * @matrix_mdev: the matrix mediated device for which we want to associate + * all available queues with a given apqi. + * @apqi: The apqi which associated with all defined APID of the + * mediated device will define a AP queue. * - * - If only @apid is not NULL, then there must be an AP queue device bound - * to the vfio_ap driver with an APQN containing @apid - * - * - If only @apqi is not NULL, then there must be an AP queue device bound - * to the vfio_ap driver with an APQN containing @apqi - * - * Returns 0 if the AP queue is reserved; otherwise, returns -EADDRNOTAVAIL. + * We remove the queue from the list of queues associated with the + * mediated device and put them back to the free list of the matrix + * device and clear the matrix_mdev pointer. */ -static int vfio_ap_verify_queue_reserved(unsigned long *apid, - unsigned long *apqi) +static void vfio_ap_put_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) { - int ret; - struct vfio_ap_queue_reserved qres; + int apid, apqn; - qres.apid = apid; - qres.apqi = apqi; - qres.reserved = false; - - ret = driver_for_each_device(&matrix_dev->vfio_ap_drv->driver, NULL, - &qres, vfio_ap_has_queue); - if (ret) - return ret; - - if (qres.reserved) - return 0; - - return -EADDRNOTAVAIL; + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { + apqn = AP_MKQID(apid, apqi); + vfio_ap_free_queue(apqn, matrix_mdev); + } } -static int -vfio_ap_mdev_verify_queues_reserved_for_apid(struct ap_matrix_mdev *matrix_mdev, - unsigned long apid) +static void move_and_set(struct list_head *src, struct list_head *dst, + struct ap_matrix_mdev *matrix_mdev) { - int ret; - unsigned long apqi; - unsigned long nbits = matrix_mdev->matrix.aqm_max + 1; - - if (find_first_bit_inv(matrix_mdev->matrix.aqm, nbits) >= nbits) - return vfio_ap_verify_queue_reserved(&apid, NULL); + struct vfio_ap_queue *q, *qtmp; - for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, nbits) { - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); - if (ret) - return ret; + list_for_each_entry_safe(q, qtmp, src, list) { + list_move(&q->list, dst); + q->matrix_mdev = matrix_mdev; } - +} +/** + * vfio_ap_get_all_domains: + * + * @matrix_mdev: the matrix mediated device for which we want to associate + * all available queues with a given apqi. + * @apqi: The apqi which associated with all defined APID of the + * mediated device will define a AP queue. + * + * We define a local list to put all queues we find on the matrix device + * free list when associating the apqi with all already defined apid for + * this matrix mediated device. + * + * If we can get all the devices we roll them to the mediated device list + * If we get errors we unroll them to the free list. + */ +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid) +{ + int apqi, apqn; + int ret = 0; + struct vfio_ap_queue *q; + struct list_head q_list; + + INIT_LIST_HEAD(&q_list); + + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { + apqn = AP_MKQID(apid, apqi); + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); + if (!q) { + ret = -EADDRNOTAVAIL; + goto rewind; + } + if (q->matrix_mdev) { + ret = -EADDRINUSE; + goto rewind; + } + list_move(&q->list, &q_list); + } + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); return 0; +rewind: + move_and_set(&q_list, &matrix_dev->free_list, NULL); + return ret; } - /** - * vfio_ap_mdev_verify_no_sharing + * vfio_ap_get_all_cards: * - * Verifies that the APQNs derived from the cross product of the AP adapter IDs - * and AP queue indexes comprising the AP matrix are not configured for another - * mediated device. AP queue sharing is not allowed. + * @matrix_mdev: the matrix mediated device for which we want to associate + * all available queues with a given apqi. + * @apqi: The apqi which associated with all defined APID of the + * mediated device will define a AP queue. * - * @matrix_mdev: the mediated matrix device + * We define a local list to put all queues we find on the matrix device + * free list when associating the apqi with all already defined apid for + * this matrix mediated device. * - * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE. + * If we can get all the devices we roll them to the mediated device list + * If we get errors we unroll them to the free list. */ -static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev) +static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi) { - struct ap_matrix_mdev *lstdev; - DECLARE_BITMAP(apm, AP_DEVICES); - DECLARE_BITMAP(aqm, AP_DOMAINS); - - list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) { - if (matrix_mdev == lstdev) - continue; - - memset(apm, 0, sizeof(apm)); - memset(aqm, 0, sizeof(aqm)); - - /* - * We work on full longs, as we can only exclude the leftover - * bits in non-inverse order. The leftover is all zeros. - */ - if (!bitmap_and(apm, matrix_mdev->matrix.apm, - lstdev->matrix.apm, AP_DEVICES)) - continue; - - if (!bitmap_and(aqm, matrix_mdev->matrix.aqm, - lstdev->matrix.aqm, AP_DOMAINS)) - continue; - - return -EADDRINUSE; + int apid, apqn; + int ret = 0; + struct vfio_ap_queue *q; + struct list_head q_list; + struct ap_matrix_mdev *tmp = NULL; + + INIT_LIST_HEAD(&q_list); + + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { + apqn = AP_MKQID(apid, apqi); + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list); + if (!q) { + ret = -EADDRNOTAVAIL; + goto rewind; + } + if (q->matrix_mdev) { + ret = -EADDRINUSE; + goto rewind; + } + list_move(&q->list, &q_list); } - + tmp = matrix_mdev; + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev); return 0; +rewind: + move_and_set(&q_list, &matrix_dev->free_list, NULL); + return ret; } /** @@ -330,21 +380,15 @@ static ssize_t assign_adapter_store(struct device *dev, */ mutex_lock(&matrix_dev->lock); - ret = vfio_ap_mdev_verify_queues_reserved_for_apid(matrix_mdev, apid); + ret = vfio_ap_get_all_domains(matrix_mdev, apid); if (ret) goto done; set_bit_inv(apid, matrix_mdev->matrix.apm); - ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); - if (ret) - goto share_err; - ret = count; goto done; -share_err: - clear_bit_inv(apid, matrix_mdev->matrix.apm); done: mutex_unlock(&matrix_dev->lock); @@ -391,32 +435,13 @@ static ssize_t unassign_adapter_store(struct device *dev, mutex_lock(&matrix_dev->lock); clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm); + vfio_ap_put_all_domains(matrix_mdev, apid); mutex_unlock(&matrix_dev->lock); return count; } static DEVICE_ATTR_WO(unassign_adapter); -static int -vfio_ap_mdev_verify_queues_reserved_for_apqi(struct ap_matrix_mdev *matrix_mdev, - unsigned long apqi) -{ - int ret; - unsigned long apid; - unsigned long nbits = matrix_mdev->matrix.apm_max + 1; - - if (find_first_bit_inv(matrix_mdev->matrix.apm, nbits) >= nbits) - return vfio_ap_verify_queue_reserved(NULL, &apqi); - - for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, nbits) { - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); - if (ret) - return ret; - } - - return 0; -} - /** * assign_domain_store * @@ -471,21 +496,15 @@ static ssize_t assign_domain_store(struct device *dev, mutex_lock(&matrix_dev->lock); - ret = vfio_ap_mdev_verify_queues_reserved_for_apqi(matrix_mdev, apqi); + ret = vfio_ap_get_all_cards(matrix_mdev, apqi); if (ret) goto done; set_bit_inv(apqi, matrix_mdev->matrix.aqm); - ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); - if (ret) - goto share_err; - ret = count; goto done; -share_err: - clear_bit_inv(apqi, matrix_mdev->matrix.aqm); done: mutex_unlock(&matrix_dev->lock); @@ -533,6 +552,7 @@ static ssize_t unassign_domain_store(struct device *dev, mutex_lock(&matrix_dev->lock); clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm); + vfio_ap_put_all_cards(matrix_mdev, apqi); mutex_unlock(&matrix_dev->lock); return count; @@ -790,49 +810,22 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, return NOTIFY_OK; } -static int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi, - unsigned int retry) -{ - struct ap_queue_status status; - - do { - status = ap_zapq(AP_MKQID(apid, apqi)); - switch (status.response_code) { - case AP_RESPONSE_NORMAL: - return 0; - case AP_RESPONSE_RESET_IN_PROGRESS: - case AP_RESPONSE_BUSY: - msleep(20); - break; - default: - /* things are really broken, give up */ - return -EIO; - } - } while (retry--); - - return -EBUSY; -} - static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev) { int ret; int rc = 0; - unsigned long apid, apqi; struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + struct vfio_ap_queue *q; - 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); - /* - * Regardless whether a queue turns out to be busy, or - * is not operational, we need to continue resetting - * the remaining queues. - */ - if (ret) - rc = ret; - } + list_for_each_entry(q, &matrix_mdev->qlist, list) { + ret = vfio_ap_mdev_reset_queue(q); + /* + * Regardless whether a queue turns out to be busy, or + * is not operational, we need to continue resetting + * the remaining queues but notice the last error code. + */ + if (ret) + rc = ret; } return rc;
We need to associate the ap_vfio_queue, which will hold the per queue information for interrupt with a matrix mediated device which hold the configuration and the way to the CRYCB. Let's do this when assigning a APID or a APQI to the mediated device and clear the relation when unassigning. Queuing the devices on a list of free devices and testing the matrix_mdev pointer to the associated matrix allow us to know if the queue is associated to the matrix device and associated or not to a mediated device. When resetting an AP queue we must wait until there are no more messages in the message queue before considering the queue is really in a clean state. Let's do it and wait until the status response code indicate the queue is empty after issuing a PAPQ/ZAPQ instruction. Being at work on the reset function, let's simplify vfio_ap_mdev_reset_queue and vfio_ap_mdev_reset_queues by using the vfio_ap_queue structure as parameter. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> --- drivers/s390/crypto/vfio_ap_ops.c | 385 +++++++++++++++++++------------------- 1 file changed, 189 insertions(+), 196 deletions(-)