From 8fb456bc9f9b136d5369f8fdd54597edd692d36d Mon Sep 17 00:00:00 2001 From: "Jason J. Herne" Date: Mon, 15 Apr 2024 11:25:54 -0400 Subject: s390/vfio-ap: Add write support to sysfs attr ap_config Allow writing a complete set of masks to ap_config. Doing so will cause the vfio-ap driver to replace the vfio-ap mediated device's matrix masks with the given set of masks. If the given state cannot be set, then no changes are made to the vfio-ap mediated device. The format of the data written to ap_config is as follows: {amask},{dmask},{cmask}\n \n is a newline character. amask, dmask, and cmask are masks identifying which adapters, domains, and control domains should be assigned to the mediated device. The format of a mask is as follows: 0xNN..NN Where NN..NN is 64 hexadecimal characters representing a 256-bit value. The leftmost (highest order) bit represents adapter/domain 0. For an example set of masks that represent your mdev's current configuration, simply cat ap_config. This attribute is intended to be used by an mdevctl callout script supporting the mdev type vfio_ap-passthrough to atomically update a vfio-ap mediated device's state. Signed-off-by: "Jason J. Herne" Reviewed-by: Tony Krowiak Tested-by: Matthew Rosato Link: https://lore.kernel.org/r/20240415152555.13152-5-jjherne@linux.ibm.com Signed-off-by: Alexander Gordeev --- drivers/s390/crypto/vfio_ap_ops.c | 190 +++++++++++++++++++++++++++++++--- drivers/s390/crypto/vfio_ap_private.h | 6 +- 2 files changed, 180 insertions(+), 16 deletions(-) (limited to 'drivers/s390') diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index 1499c2181122..9f76f2d7b66e 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -1119,20 +1119,29 @@ static void vfio_ap_mdev_unlink_adapter(struct ap_matrix_mdev *matrix_mdev, } } -static void vfio_ap_mdev_hot_unplug_adapter(struct ap_matrix_mdev *matrix_mdev, - unsigned long apid) +static void vfio_ap_mdev_hot_unplug_adapters(struct ap_matrix_mdev *matrix_mdev, + unsigned long *apids) { struct vfio_ap_queue *q, *tmpq; struct list_head qlist; + unsigned long apid; + bool apcb_update = false; INIT_LIST_HEAD(&qlist); - vfio_ap_mdev_unlink_adapter(matrix_mdev, apid, &qlist); - if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm)) { - clear_bit_inv(apid, matrix_mdev->shadow_apcb.apm); - vfio_ap_mdev_update_guest_apcb(matrix_mdev); + for_each_set_bit_inv(apid, apids, AP_DEVICES) { + vfio_ap_mdev_unlink_adapter(matrix_mdev, apid, &qlist); + + if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm)) { + clear_bit_inv(apid, matrix_mdev->shadow_apcb.apm); + apcb_update = true; + } } + /* Only update apcb if needed to avoid impacting guest */ + if (apcb_update) + vfio_ap_mdev_update_guest_apcb(matrix_mdev); + vfio_ap_mdev_reset_qlist(&qlist); list_for_each_entry_safe(q, tmpq, &qlist, reset_qnode) { @@ -1141,6 +1150,16 @@ static void vfio_ap_mdev_hot_unplug_adapter(struct ap_matrix_mdev *matrix_mdev, } } +static void vfio_ap_mdev_hot_unplug_adapter(struct ap_matrix_mdev *matrix_mdev, + unsigned long apid) +{ + DECLARE_BITMAP(apids, AP_DEVICES); + + bitmap_zero(apids, AP_DEVICES); + set_bit_inv(apid, apids); + vfio_ap_mdev_hot_unplug_adapters(matrix_mdev, apids); +} + /** * unassign_adapter_store - parses the APID from @buf and clears the * corresponding bit in the mediated matrix device's APM @@ -1301,20 +1320,29 @@ static void vfio_ap_mdev_unlink_domain(struct ap_matrix_mdev *matrix_mdev, } } -static void vfio_ap_mdev_hot_unplug_domain(struct ap_matrix_mdev *matrix_mdev, - unsigned long apqi) +static void vfio_ap_mdev_hot_unplug_domains(struct ap_matrix_mdev *matrix_mdev, + unsigned long *apqis) { struct vfio_ap_queue *q, *tmpq; struct list_head qlist; + unsigned long apqi; + bool apcb_update = false; INIT_LIST_HEAD(&qlist); - vfio_ap_mdev_unlink_domain(matrix_mdev, apqi, &qlist); - if (test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm)) { - clear_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm); - vfio_ap_mdev_update_guest_apcb(matrix_mdev); + for_each_set_bit_inv(apqi, apqis, AP_DOMAINS) { + vfio_ap_mdev_unlink_domain(matrix_mdev, apqi, &qlist); + + if (test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm)) { + clear_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm); + apcb_update = true; + } } + /* Only update apcb if needed to avoid impacting guest */ + if (apcb_update) + vfio_ap_mdev_update_guest_apcb(matrix_mdev); + vfio_ap_mdev_reset_qlist(&qlist); list_for_each_entry_safe(q, tmpq, &qlist, reset_qnode) { @@ -1323,6 +1351,16 @@ static void vfio_ap_mdev_hot_unplug_domain(struct ap_matrix_mdev *matrix_mdev, } } +static void vfio_ap_mdev_hot_unplug_domain(struct ap_matrix_mdev *matrix_mdev, + unsigned long apqi) +{ + DECLARE_BITMAP(apqis, AP_DOMAINS); + + bitmap_zero(apqis, AP_DEVICES); + set_bit_inv(apqi, apqis); + vfio_ap_mdev_hot_unplug_domains(matrix_mdev, apqis); +} + /** * unassign_domain_store - parses the APQI from @buf and clears the * corresponding bit in the mediated matrix device's AQM @@ -1590,10 +1628,136 @@ static ssize_t ap_config_show(struct device *dev, struct device_attribute *attr, return idx; } +/* Number of characters needed for a complete hex mask representing the bits in .. */ +#define AP_DEVICES_STRLEN (AP_DEVICES / 4 + 3) +#define AP_DOMAINS_STRLEN (AP_DOMAINS / 4 + 3) +#define AP_CONFIG_STRLEN (AP_DEVICES_STRLEN + 2 * AP_DOMAINS_STRLEN) + +static int parse_bitmap(char **strbufptr, unsigned long *bitmap, int nbits) +{ + char *curmask; + + curmask = strsep(strbufptr, ",\n"); + if (!curmask) + return -EINVAL; + + bitmap_clear(bitmap, 0, nbits); + return ap_hex2bitmap(curmask, bitmap, nbits); +} + +static int ap_matrix_overflow_check(struct ap_matrix_mdev *matrix_mdev) +{ + unsigned long bit; + + for_each_set_bit_inv(bit, matrix_mdev->matrix.apm, AP_DEVICES) { + if (bit > matrix_mdev->matrix.apm_max) + return -ENODEV; + } + + for_each_set_bit_inv(bit, matrix_mdev->matrix.aqm, AP_DOMAINS) { + if (bit > matrix_mdev->matrix.aqm_max) + return -ENODEV; + } + + for_each_set_bit_inv(bit, matrix_mdev->matrix.adm, AP_DOMAINS) { + if (bit > matrix_mdev->matrix.adm_max) + return -ENODEV; + } + + return 0; +} + +static void ap_matrix_copy(struct ap_matrix *dst, struct ap_matrix *src) +{ + /* This check works around false positive gcc -Wstringop-overread */ + if (!src) + return; + + bitmap_copy(dst->apm, src->apm, AP_DEVICES); + bitmap_copy(dst->aqm, src->aqm, AP_DOMAINS); + bitmap_copy(dst->adm, src->adm, AP_DOMAINS); +} + static ssize_t ap_config_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { - return count; + struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev); + struct ap_matrix m_new, m_old, m_added, m_removed; + DECLARE_BITMAP(apm_filtered, AP_DEVICES); + unsigned long newbit; + char *newbuf, *rest; + int rc = count; + bool do_update; + + newbuf = kstrndup(buf, AP_CONFIG_STRLEN, GFP_KERNEL); + if (!newbuf) + return -ENOMEM; + rest = newbuf; + + mutex_lock(&ap_perms_mutex); + get_update_locks_for_mdev(matrix_mdev); + + /* Save old state */ + ap_matrix_copy(&m_old, &matrix_mdev->matrix); + if (parse_bitmap(&rest, m_new.apm, AP_DEVICES) || + parse_bitmap(&rest, m_new.aqm, AP_DOMAINS) || + parse_bitmap(&rest, m_new.adm, AP_DOMAINS)) { + rc = -EINVAL; + goto out; + } + + bitmap_andnot(m_removed.apm, m_old.apm, m_new.apm, AP_DEVICES); + bitmap_andnot(m_removed.aqm, m_old.aqm, m_new.aqm, AP_DOMAINS); + bitmap_andnot(m_added.apm, m_new.apm, m_old.apm, AP_DEVICES); + bitmap_andnot(m_added.aqm, m_new.aqm, m_old.aqm, AP_DOMAINS); + + /* Need new bitmaps in matrix_mdev for validation */ + ap_matrix_copy(&matrix_mdev->matrix, &m_new); + + /* Ensure new state is valid, else undo new state */ + rc = vfio_ap_mdev_validate_masks(matrix_mdev); + if (rc) { + ap_matrix_copy(&matrix_mdev->matrix, &m_old); + goto out; + } + rc = ap_matrix_overflow_check(matrix_mdev); + if (rc) { + ap_matrix_copy(&matrix_mdev->matrix, &m_old); + goto out; + } + rc = count; + + /* Need old bitmaps in matrix_mdev for unplug/unlink */ + ap_matrix_copy(&matrix_mdev->matrix, &m_old); + + /* Unlink removed adapters/domains */ + vfio_ap_mdev_hot_unplug_adapters(matrix_mdev, m_removed.apm); + vfio_ap_mdev_hot_unplug_domains(matrix_mdev, m_removed.aqm); + + /* Need new bitmaps in matrix_mdev for linking new adapters/domains */ + ap_matrix_copy(&matrix_mdev->matrix, &m_new); + + /* Link newly added adapters */ + for_each_set_bit_inv(newbit, m_added.apm, AP_DEVICES) + vfio_ap_mdev_link_adapter(matrix_mdev, newbit); + + for_each_set_bit_inv(newbit, m_added.aqm, AP_DOMAINS) + vfio_ap_mdev_link_domain(matrix_mdev, newbit); + + /* filter resources not bound to vfio-ap */ + do_update = vfio_ap_mdev_filter_matrix(matrix_mdev, apm_filtered); + do_update |= vfio_ap_mdev_filter_cdoms(matrix_mdev); + + /* Apply changes to shadow apbc if things changed */ + if (do_update) { + vfio_ap_mdev_update_guest_apcb(matrix_mdev); + reset_queues_for_apids(matrix_mdev, apm_filtered); + } +out: + release_update_locks_for_mdev(matrix_mdev); + mutex_unlock(&ap_perms_mutex); + kfree(newbuf); + return rc; } static DEVICE_ATTR_RW(ap_config); diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h index 98d37aa27044..437a161c8659 100644 --- a/drivers/s390/crypto/vfio_ap_private.h +++ b/drivers/s390/crypto/vfio_ap_private.h @@ -75,11 +75,11 @@ extern struct ap_matrix_dev *matrix_dev; */ struct ap_matrix { unsigned long apm_max; - DECLARE_BITMAP(apm, 256); + DECLARE_BITMAP(apm, AP_DEVICES); unsigned long aqm_max; - DECLARE_BITMAP(aqm, 256); + DECLARE_BITMAP(aqm, AP_DOMAINS); unsigned long adm_max; - DECLARE_BITMAP(adm, 256); + DECLARE_BITMAP(adm, AP_DOMAINS); }; /** -- cgit v1.2.3