lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 27 Feb 2019 15:53:47 -0500 From: Tony Krowiak <akrowiak@...ux.ibm.com> To: Pierre Morel <pmorel@...ux.ibm.com>, borntraeger@...ibm.com Cc: alex.williamson@...hat.com, cohuck@...hat.com, linux-kernel@...r.kernel.org, linux-s390@...r.kernel.org, kvm@...r.kernel.org, frankja@...ux.ibm.com, pasic@...ux.ibm.com, david@...hat.com, schwidefsky@...ibm.com, heiko.carstens@...ibm.com, freude@...ux.ibm.com, mimu@...ux.ibm.com Subject: Re: [PATCH v4 3/7] s390: ap: associate a ap_vfio_queue and a matrix mdev 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@...ux.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/@...i 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; >
Powered by blists - more mailing lists