From e54def4ad8144ab15f826416e2e0f290ef1901b4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 19 Jun 2024 23:00:30 +0200 Subject: Adding upstream version 6.9.2. Signed-off-by: Daniel Baumann --- drivers/s390/crypto/ap_bus.c | 257 ++++++++++++++++++++++++++++++++----------- 1 file changed, 190 insertions(+), 67 deletions(-) (limited to 'drivers/s390/crypto/ap_bus.c') diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c index f46dd6aba..cce0bafd4 100644 --- a/drivers/s390/crypto/ap_bus.c +++ b/drivers/s390/crypto/ap_bus.c @@ -38,6 +38,7 @@ #include #include #include +#include #include "ap_bus.h" #include "ap_debug.h" @@ -83,14 +84,11 @@ EXPORT_SYMBOL(ap_perms); DEFINE_MUTEX(ap_perms_mutex); EXPORT_SYMBOL(ap_perms_mutex); -/* # of bus scans since init */ -static atomic64_t ap_scan_bus_count; - /* # of bindings complete since init */ static atomic64_t ap_bindings_complete_count = ATOMIC64_INIT(0); -/* completion for initial APQN bindings complete */ -static DECLARE_COMPLETION(ap_init_apqn_bindings_complete); +/* completion for APQN bindings complete */ +static DECLARE_COMPLETION(ap_apqn_bindings_complete); static struct ap_config_info *ap_qci_info; static struct ap_config_info *ap_qci_info_old; @@ -101,12 +99,16 @@ static struct ap_config_info *ap_qci_info_old; debug_info_t *ap_dbf_info; /* - * Workqueue timer for bus rescan. + * AP bus rescan related things. */ -static struct timer_list ap_config_timer; -static int ap_config_time = AP_CONFIG_TIME; -static void ap_scan_bus(struct work_struct *); -static DECLARE_WORK(ap_scan_work, ap_scan_bus); +static bool ap_scan_bus(void); +static bool ap_scan_bus_result; /* result of last ap_scan_bus() */ +static DEFINE_MUTEX(ap_scan_bus_mutex); /* mutex ap_scan_bus() invocations */ +static atomic64_t ap_scan_bus_count; /* counter ap_scan_bus() invocations */ +static int ap_scan_bus_time = AP_CONFIG_TIME; +static struct timer_list ap_scan_bus_timer; +static void ap_scan_bus_wq_callback(struct work_struct *); +static DECLARE_WORK(ap_scan_bus_work, ap_scan_bus_wq_callback); /* * Tasklet & timer for AP request polling and interrupts @@ -135,7 +137,7 @@ static int ap_max_domain_id = 15; /* Maximum adapter id, if not given via qci */ static int ap_max_adapter_id = 63; -static struct bus_type ap_bus_type; +static const struct bus_type ap_bus_type; /* Adapter interrupt definitions */ static void ap_interrupt_handler(struct airq_struct *airq, @@ -753,7 +755,7 @@ static void ap_calc_bound_apqns(unsigned int *apqns, unsigned int *bound) } /* - * After initial ap bus scan do check if all existing APQNs are + * After ap bus scan do check if all existing APQNs are * bound to device drivers. */ static void ap_check_bindings_complete(void) @@ -763,9 +765,9 @@ static void ap_check_bindings_complete(void) if (atomic64_read(&ap_scan_bus_count) >= 1) { ap_calc_bound_apqns(&apqns, &bound); if (bound == apqns) { - if (!completion_done(&ap_init_apqn_bindings_complete)) { - complete_all(&ap_init_apqn_bindings_complete); - AP_DBF_INFO("%s complete\n", __func__); + if (!completion_done(&ap_apqn_bindings_complete)) { + complete_all(&ap_apqn_bindings_complete); + pr_debug("%s all apqn bindings complete\n", __func__); } ap_send_bindings_complete_uevent(); } @@ -782,27 +784,29 @@ static void ap_check_bindings_complete(void) * -ETIME is returned. On failures negative return values are * returned to the caller. */ -int ap_wait_init_apqn_bindings_complete(unsigned long timeout) +int ap_wait_apqn_bindings_complete(unsigned long timeout) { + int rc = 0; long l; - if (completion_done(&ap_init_apqn_bindings_complete)) + if (completion_done(&ap_apqn_bindings_complete)) return 0; if (timeout) l = wait_for_completion_interruptible_timeout( - &ap_init_apqn_bindings_complete, timeout); + &ap_apqn_bindings_complete, timeout); else l = wait_for_completion_interruptible( - &ap_init_apqn_bindings_complete); + &ap_apqn_bindings_complete); if (l < 0) - return l == -ERESTARTSYS ? -EINTR : l; + rc = l == -ERESTARTSYS ? -EINTR : l; else if (l == 0 && timeout) - return -ETIME; + rc = -ETIME; - return 0; + pr_debug("%s rc=%d\n", __func__, rc); + return rc; } -EXPORT_SYMBOL(ap_wait_init_apqn_bindings_complete); +EXPORT_SYMBOL(ap_wait_apqn_bindings_complete); static int __ap_queue_devices_with_id_unregister(struct device *dev, void *data) { @@ -826,8 +830,8 @@ static int __ap_revise_reserved(struct device *dev, void *dummy) drvres = to_ap_drv(dev->driver)->flags & AP_DRIVER_FLAG_DEFAULT; if (!!devres != !!drvres) { - AP_DBF_DBG("%s reprobing queue=%02x.%04x\n", - __func__, card, queue); + pr_debug("%s reprobing queue=%02x.%04x\n", + __func__, card, queue); rc = device_reprobe(dev); if (rc) AP_DBF_WARN("%s reprobing queue=%02x.%04x failed\n", @@ -939,8 +943,6 @@ static int ap_device_probe(struct device *dev) if (is_queue_dev(dev)) hash_del(&to_ap_queue(dev)->hnode); spin_unlock_bh(&ap_queues_lock); - } else { - ap_check_bindings_complete(); } out: @@ -1012,16 +1014,47 @@ void ap_driver_unregister(struct ap_driver *ap_drv) } EXPORT_SYMBOL(ap_driver_unregister); -void ap_bus_force_rescan(void) +/* + * Enforce a synchronous AP bus rescan. + * Returns true if the bus scan finds a change in the AP configuration + * and AP devices have been added or deleted when this function returns. + */ +bool ap_bus_force_rescan(void) { + unsigned long scan_counter = atomic64_read(&ap_scan_bus_count); + bool rc = false; + + pr_debug(">%s scan counter=%lu\n", __func__, scan_counter); + /* Only trigger AP bus scans after the initial scan is done */ - if (atomic64_read(&ap_scan_bus_count) <= 0) - return; + if (scan_counter <= 0) + goto out; + + /* Try to acquire the AP scan bus mutex */ + if (mutex_trylock(&ap_scan_bus_mutex)) { + /* mutex acquired, run the AP bus scan */ + ap_scan_bus_result = ap_scan_bus(); + rc = ap_scan_bus_result; + mutex_unlock(&ap_scan_bus_mutex); + goto out; + } + + /* + * Mutex acquire failed. So there is currently another task + * already running the AP bus scan. Then let's simple wait + * for the lock which means the other task has finished and + * stored the result in ap_scan_bus_result. + */ + if (mutex_lock_interruptible(&ap_scan_bus_mutex)) { + /* some error occurred, ignore and go out */ + goto out; + } + rc = ap_scan_bus_result; + mutex_unlock(&ap_scan_bus_mutex); - /* processing a asynchronous bus rescan */ - del_timer(&ap_config_timer); - queue_work(system_long_wq, &ap_scan_work); - flush_work(&ap_scan_work); +out: + pr_debug("%s rc=%d\n", __func__, rc); + return rc; } EXPORT_SYMBOL(ap_bus_force_rescan); @@ -1030,7 +1063,7 @@ EXPORT_SYMBOL(ap_bus_force_rescan); */ void ap_bus_cfg_chg(void) { - AP_DBF_DBG("%s config change, forcing bus rescan\n", __func__); + pr_debug("%s config change, forcing bus rescan\n", __func__); ap_bus_force_rescan(); } @@ -1250,7 +1283,7 @@ static BUS_ATTR_RO(ap_interrupts); static ssize_t config_time_show(const struct bus_type *bus, char *buf) { - return sysfs_emit(buf, "%d\n", ap_config_time); + return sysfs_emit(buf, "%d\n", ap_scan_bus_time); } static ssize_t config_time_store(const struct bus_type *bus, @@ -1260,8 +1293,8 @@ static ssize_t config_time_store(const struct bus_type *bus, if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120) return -EINVAL; - ap_config_time = time; - mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ); + ap_scan_bus_time = time; + mod_timer(&ap_scan_bus_timer, jiffies + ap_scan_bus_time * HZ); return count; } @@ -1603,7 +1636,7 @@ static struct attribute *ap_bus_attrs[] = { }; ATTRIBUTE_GROUPS(ap_bus); -static struct bus_type ap_bus_type = { +static const struct bus_type ap_bus_type = { .name = "ap", .bus_groups = ap_bus_groups, .match = &ap_bus_match, @@ -1888,8 +1921,8 @@ static inline void ap_scan_domains(struct ap_card *ac) aq->last_err_rc = AP_RESPONSE_CHECKSTOPPED; } spin_unlock_bh(&aq->lock); - AP_DBF_DBG("%s(%d,%d) queue dev checkstop on\n", - __func__, ac->id, dom); + pr_debug("%s(%d,%d) queue dev checkstop on\n", + __func__, ac->id, dom); /* 'receive' pending messages with -EAGAIN */ ap_flush_queue(aq); goto put_dev_and_continue; @@ -1899,8 +1932,8 @@ static inline void ap_scan_domains(struct ap_card *ac) if (aq->dev_state > AP_DEV_STATE_UNINITIATED) _ap_queue_init_state(aq); spin_unlock_bh(&aq->lock); - AP_DBF_DBG("%s(%d,%d) queue dev checkstop off\n", - __func__, ac->id, dom); + pr_debug("%s(%d,%d) queue dev checkstop off\n", + __func__, ac->id, dom); goto put_dev_and_continue; } /* config state change */ @@ -1912,8 +1945,8 @@ static inline void ap_scan_domains(struct ap_card *ac) aq->last_err_rc = AP_RESPONSE_DECONFIGURED; } spin_unlock_bh(&aq->lock); - AP_DBF_DBG("%s(%d,%d) queue dev config off\n", - __func__, ac->id, dom); + pr_debug("%s(%d,%d) queue dev config off\n", + __func__, ac->id, dom); ap_send_config_uevent(&aq->ap_dev, aq->config); /* 'receive' pending messages with -EAGAIN */ ap_flush_queue(aq); @@ -1924,8 +1957,8 @@ static inline void ap_scan_domains(struct ap_card *ac) if (aq->dev_state > AP_DEV_STATE_UNINITIATED) _ap_queue_init_state(aq); spin_unlock_bh(&aq->lock); - AP_DBF_DBG("%s(%d,%d) queue dev config on\n", - __func__, ac->id, dom); + pr_debug("%s(%d,%d) queue dev config on\n", + __func__, ac->id, dom); ap_send_config_uevent(&aq->ap_dev, aq->config); goto put_dev_and_continue; } @@ -1997,8 +2030,8 @@ static inline void ap_scan_adapter(int ap) ap_scan_rm_card_dev_and_queue_devs(ac); put_device(dev); } else { - AP_DBF_DBG("%s(%d) no type info (no APQN found), ignored\n", - __func__, ap); + pr_debug("%s(%d) no type info (no APQN found), ignored\n", + __func__, ap); } return; } @@ -2010,8 +2043,8 @@ static inline void ap_scan_adapter(int ap) ap_scan_rm_card_dev_and_queue_devs(ac); put_device(dev); } else { - AP_DBF_DBG("%s(%d) no valid type (0) info, ignored\n", - __func__, ap); + pr_debug("%s(%d) no valid type (0) info, ignored\n", + __func__, ap); } return; } @@ -2135,23 +2168,80 @@ static bool ap_get_configuration(void) sizeof(struct ap_config_info)) != 0; } +/* + * ap_config_has_new_aps - Check current against old qci info if + * new adapters have appeared. Returns true if at least one new + * adapter in the apm mask is showing up. Existing adapters or + * receding adapters are not counted. + */ +static bool ap_config_has_new_aps(void) +{ + + unsigned long m[BITS_TO_LONGS(AP_DEVICES)]; + + if (!ap_qci_info) + return false; + + bitmap_andnot(m, (unsigned long *)ap_qci_info->apm, + (unsigned long *)ap_qci_info_old->apm, AP_DEVICES); + if (!bitmap_empty(m, AP_DEVICES)) + return true; + + return false; +} + +/* + * ap_config_has_new_doms - Check current against old qci info if + * new (usage) domains have appeared. Returns true if at least one + * new domain in the aqm mask is showing up. Existing domains or + * receding domains are not counted. + */ +static bool ap_config_has_new_doms(void) +{ + unsigned long m[BITS_TO_LONGS(AP_DOMAINS)]; + + if (!ap_qci_info) + return false; + + bitmap_andnot(m, (unsigned long *)ap_qci_info->aqm, + (unsigned long *)ap_qci_info_old->aqm, AP_DOMAINS); + if (!bitmap_empty(m, AP_DOMAINS)) + return true; + + return false; +} + /** * ap_scan_bus(): Scan the AP bus for new devices - * Runs periodically, workqueue timer (ap_config_time) - * @unused: Unused pointer. + * Always run under mutex ap_scan_bus_mutex protection + * which needs to get locked/unlocked by the caller! + * Returns true if any config change has been detected + * during the scan, otherwise false. */ -static void ap_scan_bus(struct work_struct *unused) +static bool ap_scan_bus(void) { - int ap, config_changed = 0; + bool config_changed; + int ap; + + pr_debug(">%s\n", __func__); - /* config change notify */ + /* (re-)fetch configuration via QCI */ config_changed = ap_get_configuration(); - if (config_changed) + if (config_changed) { + if (ap_config_has_new_aps() || ap_config_has_new_doms()) { + /* + * Appearance of new adapters and/or domains need to + * build new ap devices which need to get bound to an + * device driver. Thus reset the APQN bindings complete + * completion. + */ + reinit_completion(&ap_apqn_bindings_complete); + } + /* post a config change notify */ notify_config_changed(); + } ap_select_domain(); - AP_DBF_DBG("%s running\n", __func__); - /* loop over all possible adapters */ for (ap = 0; ap <= ap_max_adapter_id; ap++) ap_scan_adapter(ap); @@ -2174,23 +2264,56 @@ static void ap_scan_bus(struct work_struct *unused) } if (atomic64_inc_return(&ap_scan_bus_count) == 1) { - AP_DBF_DBG("%s init scan complete\n", __func__); + pr_debug("%s init scan complete\n", __func__); ap_send_init_scan_done_uevent(); - ap_check_bindings_complete(); } - mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ); + ap_check_bindings_complete(); + + mod_timer(&ap_scan_bus_timer, jiffies + ap_scan_bus_time * HZ); + + pr_debug("<%s config_changed=%d\n", __func__, config_changed); + + return config_changed; } -static void ap_config_timeout(struct timer_list *unused) +/* + * Callback for the ap_scan_bus_timer + * Runs periodically, workqueue timer (ap_scan_bus_time) + */ +static void ap_scan_bus_timer_callback(struct timer_list *unused) { - queue_work(system_long_wq, &ap_scan_work); + /* + * schedule work into the system long wq which when + * the work is finally executed, calls the AP bus scan. + */ + queue_work(system_long_wq, &ap_scan_bus_work); +} + +/* + * Callback for the ap_scan_bus_work + */ +static void ap_scan_bus_wq_callback(struct work_struct *unused) +{ + /* + * Try to invoke an ap_scan_bus(). If the mutex acquisition + * fails there is currently another task already running the + * AP scan bus and there is no need to wait and re-trigger the + * scan again. Please note at the end of the scan bus function + * the AP scan bus timer is re-armed which triggers then the + * ap_scan_bus_timer_callback which enqueues a work into the + * system_long_wq which invokes this function here again. + */ + if (mutex_trylock(&ap_scan_bus_mutex)) { + ap_scan_bus_result = ap_scan_bus(); + mutex_unlock(&ap_scan_bus_mutex); + } } static int __init ap_debug_init(void) { ap_dbf_info = debug_register("ap", 2, 1, - DBF_MAX_SPRINTF_ARGS * sizeof(long)); + AP_DBF_MAX_SPRINTF_ARGS * sizeof(long)); debug_register_view(ap_dbf_info, &debug_sprintf_view); debug_set_level(ap_dbf_info, DBF_ERR); @@ -2274,7 +2397,7 @@ static int __init ap_module_init(void) ap_root_device->bus = &ap_bus_type; /* Setup the AP bus rescan timer. */ - timer_setup(&ap_config_timer, ap_config_timeout, 0); + timer_setup(&ap_scan_bus_timer, ap_scan_bus_timer_callback, 0); /* * Setup the high resolution poll timer. @@ -2292,7 +2415,7 @@ static int __init ap_module_init(void) goto out_work; } - queue_work(system_long_wq, &ap_scan_work); + queue_work(system_long_wq, &ap_scan_bus_work); return 0; -- cgit v1.2.3