From 3f3007afda8bb731a3422430752ca91ddc102e4d Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Mon, 14 Sep 2015 17:01:23 +0200 Subject: [PATCH] s390/zcrypt: introduce state machine for the AP bus Replace the two fields 'unregistered' and 'reset' with a device state with 5 possible values. Introduce two events for the AP devices, device poll and device timeout. With the state machine it is easier to deal with device initialization and suspend/resume. Device polling is simpler as well, the arkane 'flags' passing is gone. Reviewd-by: Ingo Tuchscherer Signed-off-by: Martin Schwidefsky --- drivers/s390/crypto/ap_bus.c | 1033 ++++++++++++++++------------------ drivers/s390/crypto/ap_bus.h | 53 +- 2 files changed, 522 insertions(+), 564 deletions(-) diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c index 7224bf7fa9bf..92d3b67b3839 100644 --- a/drivers/s390/crypto/ap_bus.c +++ b/drivers/s390/crypto/ap_bus.c @@ -49,17 +49,6 @@ #include "ap_bus.h" -/* Some prototypes. */ -static void ap_scan_bus(struct work_struct *); -static void ap_poll_all(unsigned long); -static void ap_request_timeout(unsigned long); -static int __ap_poll_device(struct ap_device *ap_dev, unsigned long *flags); -static int ap_device_remove(struct device *dev); -static int ap_device_probe(struct device *dev); -static void ap_interrupt_handler(struct airq_struct *airq); -static void ap_reset(struct ap_device *ap_dev, unsigned long *flags); -static int ap_select_domain(void); - /* * Module description. */ @@ -92,12 +81,14 @@ static LIST_HEAD(ap_device_list); static struct workqueue_struct *ap_work_queue; 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_config_work, ap_scan_bus); /* * Tasklet & timer for AP request polling and interrupts */ -static DECLARE_TASKLET(ap_tasklet, ap_poll_all, 0); +static void ap_tasklet_fn(unsigned long); +static DECLARE_TASKLET(ap_tasklet, ap_tasklet_fn, 0); static atomic_t ap_poll_requests = ATOMIC_INIT(0); static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait); static struct task_struct *ap_poll_kthread = NULL; @@ -119,6 +110,8 @@ static int user_set_domain = 0; static struct bus_type ap_bus_type; /* Adapter interrupt definitions */ +static void ap_interrupt_handler(struct airq_struct *airq); + static int ap_airq_flag; static struct airq_struct ap_airq = { @@ -343,7 +336,9 @@ static int ap_queue_enable_interruption(struct ap_device *ap_dev, void *ind) case AP_RESPONSE_DECONFIGURED: case AP_RESPONSE_CHECKSTOPPED: case AP_RESPONSE_INVALID_ADDRESS: - return -ENODEV; + pr_err("Registering adapter interrupts for AP %d failed\n", + AP_QID_DEVICE(ap_dev->qid)); + return -EOPNOTSUPP; case AP_RESPONSE_RESET_IN_PROGRESS: case AP_RESPONSE_BUSY: default: @@ -468,37 +463,6 @@ int ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length) } EXPORT_SYMBOL(ap_recv); -/** - * __ap_schedule_poll_timer(): Schedule poll timer. - * - * Set up the timer to run the poll tasklet - */ -static inline void __ap_schedule_poll_timer(void) -{ - ktime_t hr_time; - - spin_lock_bh(&ap_poll_timer_lock); - if (!hrtimer_is_queued(&ap_poll_timer) && !ap_suspend_flag) { - hr_time = ktime_set(0, poll_timeout); - hrtimer_forward_now(&ap_poll_timer, hr_time); - hrtimer_restart(&ap_poll_timer); - } - spin_unlock_bh(&ap_poll_timer_lock); -} - -/** - * ap_schedule_poll_timer(): Schedule poll timer. - * - * Set up the timer to run the poll tasklet - */ -static inline void ap_schedule_poll_timer(void) -{ - if (ap_using_interrupts()) - return; - __ap_schedule_poll_timer(); -} - - /** * ap_query_queue(): Check if an AP queue is available. * @qid: The AP queue number @@ -541,73 +505,404 @@ static int ap_query_queue(ap_qid_t qid, int *queue_depth, int *device_type, } } +/* State machine definitions and helpers */ + +static void ap_sm_wait(enum ap_wait wait) +{ + ktime_t hr_time; + + switch (wait) { + case AP_WAIT_AGAIN: + case AP_WAIT_INTERRUPT: + if (ap_using_interrupts()) + break; + if (ap_poll_kthread) { + wake_up(&ap_poll_wait); + break; + } + /* Fall through */ + case AP_WAIT_TIMEOUT: + spin_lock_bh(&ap_poll_timer_lock); + if (!hrtimer_is_queued(&ap_poll_timer)) { + hr_time = ktime_set(0, poll_timeout); + hrtimer_forward_now(&ap_poll_timer, hr_time); + hrtimer_restart(&ap_poll_timer); + } + spin_unlock_bh(&ap_poll_timer_lock); + break; + case AP_WAIT_NONE: + default: + break; + } +} + +static enum ap_wait ap_sm_nop(struct ap_device *ap_dev) +{ + return AP_WAIT_NONE; +} + +/** + * ap_sm_recv(): Receive pending reply messages from an AP device but do + * not change the state of the device. + * @ap_dev: pointer to the AP device + * + * Returns AP_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT + */ +static struct ap_queue_status ap_sm_recv(struct ap_device *ap_dev) +{ + struct ap_queue_status status; + struct ap_message *ap_msg; + + status = __ap_recv(ap_dev->qid, &ap_dev->reply->psmid, + ap_dev->reply->message, ap_dev->reply->length); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + atomic_dec(&ap_poll_requests); + ap_dev->queue_count--; + if (ap_dev->queue_count > 0) + mod_timer(&ap_dev->timeout, + jiffies + ap_dev->drv->request_timeout); + list_for_each_entry(ap_msg, &ap_dev->pendingq, list) { + if (ap_msg->psmid != ap_dev->reply->psmid) + continue; + list_del_init(&ap_msg->list); + ap_dev->pendingq_count--; + ap_msg->receive(ap_dev, ap_msg, ap_dev->reply); + break; + } + case AP_RESPONSE_NO_PENDING_REPLY: + if (!status.queue_empty || ap_dev->queue_count <= 0) + break; + /* The card shouldn't forget requests but who knows. */ + atomic_sub(ap_dev->queue_count, &ap_poll_requests); + ap_dev->queue_count = 0; + list_splice_init(&ap_dev->pendingq, &ap_dev->requestq); + ap_dev->requestq_count += ap_dev->pendingq_count; + ap_dev->pendingq_count = 0; + break; + default: + break; + } + return status; +} + +/** + * ap_sm_read(): Receive pending reply messages from an AP device. + * @ap_dev: pointer to the AP device + * + * Returns AP_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT + */ +static enum ap_wait ap_sm_read(struct ap_device *ap_dev) +{ + struct ap_queue_status status; + + status = ap_sm_recv(ap_dev); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + if (ap_dev->queue_count > 0) + return AP_WAIT_AGAIN; + ap_dev->state = AP_STATE_IDLE; + return AP_WAIT_NONE; + case AP_RESPONSE_NO_PENDING_REPLY: + if (ap_dev->queue_count > 0) + return AP_WAIT_INTERRUPT; + ap_dev->state = AP_STATE_IDLE; + return AP_WAIT_NONE; + default: + ap_dev->state = AP_STATE_BORKED; + return AP_WAIT_NONE; + } +} + +/** + * ap_sm_write(): Send messages from the request queue to an AP device. + * @ap_dev: pointer to the AP device + * + * Returns AP_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT + */ +static enum ap_wait ap_sm_write(struct ap_device *ap_dev) +{ + struct ap_queue_status status; + struct ap_message *ap_msg; + + if (ap_dev->requestq_count <= 0) + return AP_WAIT_NONE; + /* Start the next request on the queue. */ + ap_msg = list_entry(ap_dev->requestq.next, struct ap_message, list); + status = __ap_send(ap_dev->qid, ap_msg->psmid, + ap_msg->message, ap_msg->length, ap_msg->special); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + atomic_inc(&ap_poll_requests); + ap_dev->queue_count++; + if (ap_dev->queue_count == 1) + mod_timer(&ap_dev->timeout, + jiffies + ap_dev->drv->request_timeout); + list_move_tail(&ap_msg->list, &ap_dev->pendingq); + ap_dev->requestq_count--; + ap_dev->pendingq_count++; + if (ap_dev->queue_count < ap_dev->queue_depth) { + ap_dev->state = AP_STATE_WORKING; + return AP_WAIT_AGAIN; + } + /* fall through */ + case AP_RESPONSE_Q_FULL: + ap_dev->state = AP_STATE_QUEUE_FULL; + return AP_WAIT_INTERRUPT; + case AP_RESPONSE_RESET_IN_PROGRESS: + ap_dev->state = AP_STATE_RESET_WAIT; + return AP_WAIT_TIMEOUT; + case AP_RESPONSE_MESSAGE_TOO_BIG: + case AP_RESPONSE_REQ_FAC_NOT_INST: + list_del_init(&ap_msg->list); + ap_dev->requestq_count--; + ap_msg->rc = -EINVAL; + ap_msg->receive(ap_dev, ap_msg, NULL); + return AP_WAIT_AGAIN; + default: + ap_dev->state = AP_STATE_BORKED; + return AP_WAIT_NONE; + } +} + /** - * ap_init_queue(): Reset an AP queue. + * ap_sm_read_write(): Send and receive messages to/from an AP device. + * @ap_dev: pointer to the AP device + * + * Returns AP_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT + */ +static enum ap_wait ap_sm_read_write(struct ap_device *ap_dev) +{ + return min(ap_sm_read(ap_dev), ap_sm_write(ap_dev)); +} + +/** + * ap_sm_reset(): Reset an AP queue. * @qid: The AP queue number * * Submit the Reset command to an AP queue. - * Since the reset is asynchron set the state to 'RESET_IN_PROGRESS' - * and check later via ap_poll_queue() if the reset is done. */ -static int ap_init_queue(struct ap_device *ap_dev) +static enum ap_wait ap_sm_reset(struct ap_device *ap_dev) { struct ap_queue_status status; status = ap_reset_queue(ap_dev->qid); switch (status.response_code) { case AP_RESPONSE_NORMAL: - ap_dev->interrupt = AP_INTR_DISABLED; - ap_dev->reset = AP_RESET_IN_PROGRESS; - return 0; case AP_RESPONSE_RESET_IN_PROGRESS: + ap_dev->state = AP_STATE_RESET_WAIT; + ap_dev->interrupt = AP_INTR_DISABLED; + return AP_WAIT_TIMEOUT; case AP_RESPONSE_BUSY: - return -EBUSY; + return AP_WAIT_TIMEOUT; case AP_RESPONSE_Q_NOT_AVAIL: case AP_RESPONSE_DECONFIGURED: case AP_RESPONSE_CHECKSTOPPED: default: - return -ENODEV; + ap_dev->state = AP_STATE_BORKED; + return AP_WAIT_NONE; } } /** - * ap_increase_queue_count(): Arm request timeout. - * @ap_dev: Pointer to an AP device. + * ap_sm_reset_wait(): Test queue for completion of the reset operation + * @ap_dev: pointer to the AP device * - * Arm request timeout if an AP device was idle and a new request is submitted. + * Returns AP_POLL_IMMEDIATELY, AP_POLL_AFTER_TIMEROUT or 0. */ -static void ap_increase_queue_count(struct ap_device *ap_dev) +static enum ap_wait ap_sm_reset_wait(struct ap_device *ap_dev) { - int timeout = ap_dev->drv->request_timeout; + struct ap_queue_status status; + unsigned long info; - ap_dev->queue_count++; - if (ap_dev->queue_count == 1) { - mod_timer(&ap_dev->timeout, jiffies + timeout); - ap_dev->reset = AP_RESET_ARMED; + if (ap_dev->queue_count > 0) + /* Try to read a completed message and get the status */ + status = ap_sm_recv(ap_dev); + else + /* Get the status with TAPQ */ + status = ap_test_queue(ap_dev->qid, &info); + + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + if (ap_using_interrupts() && + ap_queue_enable_interruption(ap_dev, + ap_airq.lsi_ptr) == 0) + ap_dev->state = AP_STATE_SETIRQ_WAIT; + else + ap_dev->state = (ap_dev->queue_count > 0) ? + AP_STATE_WORKING : AP_STATE_IDLE; + return AP_WAIT_AGAIN; + case AP_RESPONSE_BUSY: + case AP_RESPONSE_RESET_IN_PROGRESS: + return AP_WAIT_TIMEOUT; + case AP_RESPONSE_Q_NOT_AVAIL: + case AP_RESPONSE_DECONFIGURED: + case AP_RESPONSE_CHECKSTOPPED: + default: + ap_dev->state = AP_STATE_BORKED; + return AP_WAIT_NONE; } } /** - * ap_decrease_queue_count(): Decrease queue count. - * @ap_dev: Pointer to an AP device. + * ap_sm_setirq_wait(): Test queue for completion of the irq enablement + * @ap_dev: pointer to the AP device * - * If AP device is still alive, re-schedule request timeout if there are still - * pending requests. + * Returns AP_POLL_IMMEDIATELY, AP_POLL_AFTER_TIMEROUT or 0. */ -static void ap_decrease_queue_count(struct ap_device *ap_dev) +static enum ap_wait ap_sm_setirq_wait(struct ap_device *ap_dev) { - int timeout = ap_dev->drv->request_timeout; + struct ap_queue_status status; + unsigned long info; - ap_dev->queue_count--; if (ap_dev->queue_count > 0) - mod_timer(&ap_dev->timeout, jiffies + timeout); + /* Try to read a completed message and get the status */ + status = ap_sm_recv(ap_dev); else - /* - * The timeout timer should to be disabled now - since - * del_timer_sync() is very expensive, we just tell via the - * reset flag to ignore the pending timeout timer. - */ - ap_dev->reset = AP_RESET_IGNORE; + /* Get the status with TAPQ */ + status = ap_test_queue(ap_dev->qid, &info); + + if (status.int_enabled == 1) { + /* Irqs are now enabled */ + ap_dev->interrupt = AP_INTR_ENABLED; + ap_dev->state = (ap_dev->queue_count > 0) ? + AP_STATE_WORKING : AP_STATE_IDLE; + } + + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + if (ap_dev->queue_count > 0) + return AP_WAIT_AGAIN; + /* fallthrough */ + case AP_RESPONSE_NO_PENDING_REPLY: + return AP_WAIT_TIMEOUT; + default: + ap_dev->state = AP_STATE_BORKED; + return AP_WAIT_NONE; + } +} + +/* + * AP state machine jump table + */ +ap_func_t *ap_jumptable[NR_AP_STATES][NR_AP_EVENTS] = { + [AP_STATE_RESET_START] = { + [AP_EVENT_POLL] = ap_sm_reset, + [AP_EVENT_TIMEOUT] = ap_sm_nop, + }, + [AP_STATE_RESET_WAIT] = { + [AP_EVENT_POLL] = ap_sm_reset_wait, + [AP_EVENT_TIMEOUT] = ap_sm_nop, + }, + [AP_STATE_SETIRQ_WAIT] = { + [AP_EVENT_POLL] = ap_sm_setirq_wait, + [AP_EVENT_TIMEOUT] = ap_sm_nop, + }, + [AP_STATE_IDLE] = { + [AP_EVENT_POLL] = ap_sm_write, + [AP_EVENT_TIMEOUT] = ap_sm_nop, + }, + [AP_STATE_WORKING] = { + [AP_EVENT_POLL] = ap_sm_read_write, + [AP_EVENT_TIMEOUT] = ap_sm_reset, + }, + [AP_STATE_QUEUE_FULL] = { + [AP_EVENT_POLL] = ap_sm_read, + [AP_EVENT_TIMEOUT] = ap_sm_reset, + }, + [AP_STATE_SUSPEND_WAIT] = { + [AP_EVENT_POLL] = ap_sm_read, + [AP_EVENT_TIMEOUT] = ap_sm_nop, + }, + [AP_STATE_BORKED] = { + [AP_EVENT_POLL] = ap_sm_nop, + [AP_EVENT_TIMEOUT] = ap_sm_nop, + }, +}; + +static inline enum ap_wait ap_sm_event(struct ap_device *ap_dev, + enum ap_event event) +{ + return ap_jumptable[ap_dev->state][event](ap_dev); +} + +static inline enum ap_wait ap_sm_event_loop(struct ap_device *ap_dev, + enum ap_event event) +{ + enum ap_wait wait; + + while ((wait = ap_sm_event(ap_dev, event)) == AP_WAIT_AGAIN) + ; + return wait; +} + +/** + * ap_request_timeout(): Handling of request timeouts + * @data: Holds the AP device. + * + * Handles request timeouts. + */ +static void ap_request_timeout(unsigned long data) +{ + struct ap_device *ap_dev = (struct ap_device *) data; + + if (ap_suspend_flag) + return; + spin_lock_bh(&ap_dev->lock); + ap_sm_wait(ap_sm_event(ap_dev, AP_EVENT_TIMEOUT)); + spin_unlock_bh(&ap_dev->lock); +} + +/** + * ap_poll_timeout(): AP receive polling for finished AP requests. + * @unused: Unused pointer. + * + * Schedules the AP tasklet using a high resolution timer. + */ +static enum hrtimer_restart ap_poll_timeout(struct hrtimer *unused) +{ + if (!ap_suspend_flag) + tasklet_schedule(&ap_tasklet); + return HRTIMER_NORESTART; +} + +/** + * ap_interrupt_handler() - Schedule ap_tasklet on interrupt + * @airq: pointer to adapter interrupt descriptor + */ +static void ap_interrupt_handler(struct airq_struct *airq) +{ + inc_irq_stat(IRQIO_APB); + if (!ap_suspend_flag) + tasklet_schedule(&ap_tasklet); +} + +/** + * ap_tasklet_fn(): Tasklet to poll all AP devices. + * @dummy: Unused variable + * + * Poll all AP devices on the bus. + */ +static void ap_tasklet_fn(unsigned long dummy) +{ + struct ap_device *ap_dev; + enum ap_wait wait = AP_WAIT_NONE; + + /* Reset the indicator if interrupts are used. Thus new interrupts can + * be received. Doing it in the beginning of the tasklet is therefor + * important that no requests on any AP get lost. + */ + if (ap_using_interrupts()) + xchg(ap_airq.lsi_ptr, 0); + + spin_lock(&ap_device_list_lock); + list_for_each_entry(ap_dev, &ap_device_list, list) { + spin_lock_bh(&ap_dev->lock); + wait = min(wait, ap_sm_event_loop(ap_dev, AP_EVENT_POLL)); + spin_unlock_bh(&ap_dev->lock); + } + spin_unlock(&ap_device_list_lock); + ap_sm_wait(wait); } /** @@ -623,8 +918,6 @@ static void ap_decrease_queue_count(struct ap_device *ap_dev) static int ap_poll_thread(void *data) { DECLARE_WAITQUEUE(wait, current); - unsigned long flags; - struct ap_device *ap_dev; set_user_nice(current, MAX_NICE); set_freezable(); @@ -638,21 +931,12 @@ static int ap_poll_thread(void *data) } set_current_state(TASK_RUNNING); remove_wait_queue(&ap_poll_wait, &wait); - if (need_resched()) { schedule(); try_to_freeze(); continue; } - - flags = 0; - spin_lock_bh(&ap_device_list_lock); - list_for_each_entry(ap_dev, &ap_device_list, list) { - spin_lock(&ap_dev->lock); - __ap_poll_device(ap_dev, &flags); - spin_unlock(&ap_dev->lock); - } - spin_unlock_bh(&ap_device_list_lock); + ap_tasklet_fn(0); } while (!kthread_should_stop()); return 0; } @@ -682,6 +966,57 @@ static void ap_poll_thread_stop(void) mutex_unlock(&ap_poll_thread_mutex); } +/** + * ap_queue_message(): Queue a request to an AP device. + * @ap_dev: The AP device to queue the message to + * @ap_msg: The message that is to be added + */ +void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg) +{ + /* For asynchronous message handling a valid receive-callback + * is required. */ + BUG_ON(!ap_msg->receive); + + spin_lock_bh(&ap_dev->lock); + /* Queue the message. */ + list_add_tail(&ap_msg->list, &ap_dev->requestq); + ap_dev->requestq_count++; + ap_dev->total_request_count++; + /* Send/receive as many request from the queue as possible. */ + ap_sm_wait(ap_sm_event_loop(ap_dev, AP_EVENT_POLL)); + spin_unlock_bh(&ap_dev->lock); +} +EXPORT_SYMBOL(ap_queue_message); + +/** + * ap_cancel_message(): Cancel a crypto request. + * @ap_dev: The AP device that has the message queued + * @ap_msg: The message that is to be removed + * + * Cancel a crypto request. This is done by removing the request + * from the device pending or request queue. Note that the + * request stays on the AP queue. When it finishes the message + * reply will be discarded because the psmid can't be found. + */ +void ap_cancel_message(struct ap_device *ap_dev, struct ap_message *ap_msg) +{ + struct ap_message *tmp; + + spin_lock_bh(&ap_dev->lock); + if (!list_empty(&ap_msg->list)) { + list_for_each_entry(tmp, &ap_dev->pendingq, list) + if (tmp->psmid == ap_msg->psmid) { + ap_dev->pendingq_count--; + goto found; + } + ap_dev->requestq_count--; +found: + list_del_init(&ap_msg->list); + } + spin_unlock_bh(&ap_dev->lock); +} +EXPORT_SYMBOL(ap_cancel_message); + /* * AP device related attributes. */ @@ -762,21 +1097,17 @@ static ssize_t ap_reset_show(struct device *dev, int rc = 0; spin_lock_bh(&ap_dev->lock); - switch (ap_dev->reset) { - case AP_RESET_IGNORE: - rc = snprintf(buf, PAGE_SIZE, "No Reset Timer set.\n"); + switch (ap_dev->state) { + case AP_STATE_RESET_START: + case AP_STATE_RESET_WAIT: + rc = snprintf(buf, PAGE_SIZE, "Reset in progress.\n"); break; - case AP_RESET_ARMED: + case AP_STATE_WORKING: + case AP_STATE_QUEUE_FULL: rc = snprintf(buf, PAGE_SIZE, "Reset Timer armed.\n"); break; - case AP_RESET_DO: - rc = snprintf(buf, PAGE_SIZE, "Reset Timer expired.\n"); - break; - case AP_RESET_IN_PROGRESS: - rc = snprintf(buf, PAGE_SIZE, "Reset in progress.\n"); - break; default: - break; + rc = snprintf(buf, PAGE_SIZE, "No Reset Timer set.\n"); } spin_unlock_bh(&ap_dev->lock); return rc; @@ -791,17 +1122,12 @@ static ssize_t ap_interrupt_show(struct device *dev, int rc = 0; spin_lock_bh(&ap_dev->lock); - switch (ap_dev->interrupt) { - case AP_INTR_DISABLED: - rc = snprintf(buf, PAGE_SIZE, "Interrupts disabled.\n"); - break; - case AP_INTR_ENABLED: - rc = snprintf(buf, PAGE_SIZE, "Interrupts enabled.\n"); - break; - case AP_INTR_IN_PROGRESS: + if (ap_dev->state == AP_STATE_SETIRQ_WAIT) rc = snprintf(buf, PAGE_SIZE, "Enable Interrupt pending.\n"); - break; - } + else if (ap_dev->interrupt == AP_INTR_ENABLED) + rc = snprintf(buf, PAGE_SIZE, "Interrupts enabled.\n"); + else + rc = snprintf(buf, PAGE_SIZE, "Interrupts disabled.\n"); spin_unlock_bh(&ap_dev->lock); return rc; } @@ -898,16 +1224,14 @@ static int ap_uevent (struct device *dev, struct kobj_uevent_env *env) static int ap_dev_suspend(struct device *dev, pm_message_t state) { struct ap_device *ap_dev = to_ap_dev(dev); - unsigned long flags; /* Poll on the device until all requests are finished. */ - do { - flags = 0; - spin_lock_bh(&ap_dev->lock); - __ap_poll_device(ap_dev, &flags); - spin_unlock_bh(&ap_dev->lock); - } while ((flags & 1) || (flags & 2)); - + spin_lock_bh(&ap_dev->lock); + ap_dev->state = AP_STATE_SUSPEND_WAIT; + while (ap_sm_event(ap_dev, AP_EVENT_POLL) != AP_WAIT_NONE) + ; + ap_dev->state = AP_STATE_BORKED; + spin_unlock_bh(&ap_dev->lock); return 0; } @@ -957,7 +1281,6 @@ static void ap_bus_resume(void) xchg(ap_airq.lsi_ptr, 0); tasklet_enable(&ap_tasklet); queue_work(ap_work_queue, &ap_config_work); - wake_up(&ap_poll_wait); } static int ap_power_event(struct notifier_block *this, unsigned long event, @@ -993,24 +1316,12 @@ static int ap_device_probe(struct device *dev) { struct ap_device *ap_dev = to_ap_dev(dev); struct ap_driver *ap_drv = to_ap_drv(dev->driver); - int rc; - - ap_dev->drv = ap_drv; - - spin_lock_bh(&ap_device_list_lock); - list_add(&ap_dev->list, &ap_device_list); - spin_unlock_bh(&ap_device_list_lock); + int rc; + ap_dev->drv = ap_drv; rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV; - if (rc) { - spin_lock_bh(&ap_device_list_lock); - list_del_init(&ap_dev->list); - spin_unlock_bh(&ap_device_list_lock); - } else { - if (ap_dev->reset == AP_RESET_IN_PROGRESS || - ap_dev->interrupt == AP_INTR_IN_PROGRESS) - __ap_schedule_poll_timer(); - } + if (rc) + ap_dev->drv = NULL; return rc; } @@ -1064,6 +1375,11 @@ static int ap_device_remove(struct device *dev) return 0; } +static void ap_device_release(struct device *dev) +{ + kfree(to_ap_dev(dev)); +} + int ap_driver_register(struct ap_driver *ap_drv, struct module *owner, char *name) { @@ -1371,13 +1687,6 @@ out: return rc; } -static void ap_interrupt_handler(struct airq_struct *airq) -{ - inc_irq_stat(IRQIO_APB); - if (!ap_suspend_flag) - tasklet_schedule(&ap_tasklet); -} - /** * __ap_scan_bus(): Scan the AP bus. * @dev: Pointer to device @@ -1390,21 +1699,14 @@ static int __ap_scan_bus(struct device *dev, void *data) return to_ap_dev(dev)->qid == (ap_qid_t)(unsigned long) data; } -static void ap_device_release(struct device *dev) -{ - struct ap_device *ap_dev = to_ap_dev(dev); - - kfree(ap_dev); -} - static void ap_scan_bus(struct work_struct *unused) { struct ap_device *ap_dev; struct device *dev; ap_qid_t qid; int queue_depth = 0, device_type = 0; - unsigned int device_functions; - int rc, i; + unsigned int device_functions = 0; + int rc, i, borked; ap_query_configuration(); if (ap_select_domain() != 0) @@ -1420,17 +1722,15 @@ static void ap_scan_bus(struct work_struct *unused) if (dev) { ap_dev = to_ap_dev(dev); spin_lock_bh(&ap_dev->lock); - if (rc == -ENODEV || ap_dev->unregistered) { - spin_unlock_bh(&ap_dev->lock); - if (ap_dev->unregistered) - i--; - device_unregister(dev); - put_device(dev); - continue; - } + if (rc == -ENODEV) + ap_dev->state = AP_STATE_BORKED; + borked = ap_dev->state == AP_STATE_BORKED; spin_unlock_bh(&ap_dev->lock); + if (borked) /* Remove broken device */ + device_unregister(dev); put_device(dev); - continue; + if (!borked) + continue; } if (rc) continue; @@ -1438,16 +1738,12 @@ static void ap_scan_bus(struct work_struct *unused) if (!ap_dev) break; ap_dev->qid = qid; - rc = ap_init_queue(ap_dev); - if ((rc != 0) && (rc != -EBUSY)) { - kfree(ap_dev); - continue; - } + ap_dev->state = AP_STATE_RESET_START; + ap_dev->interrupt = AP_INTR_DISABLED; ap_dev->queue_depth = queue_depth; ap_dev->raw_hwtype = device_type; ap_dev->device_type = device_type; ap_dev->functions = device_functions; - ap_dev->unregistered = 1; spin_lock_init(&ap_dev->lock); INIT_LIST_HEAD(&ap_dev->pendingq); INIT_LIST_HEAD(&ap_dev->requestq); @@ -1463,27 +1759,37 @@ static void ap_scan_bus(struct work_struct *unused) ap_dev->device.bus = &ap_bus_type; ap_dev->device.parent = ap_root_device; - if (dev_set_name(&ap_dev->device, "card%02x", - AP_QID_DEVICE(ap_dev->qid))) { + rc = dev_set_name(&ap_dev->device, "card%02x", + AP_QID_DEVICE(ap_dev->qid)); + if (rc) { kfree(ap_dev); continue; } + /* Add to list of devices */ + spin_lock_bh(&ap_device_list_lock); + list_add(&ap_dev->list, &ap_device_list); + spin_unlock_bh(&ap_device_list_lock); + /* Start with a device reset */ + spin_lock_bh(&ap_dev->lock); + ap_sm_wait(ap_sm_event(ap_dev, AP_EVENT_POLL)); + spin_unlock_bh(&ap_dev->lock); + /* Register device */ ap_dev->device.release = ap_device_release; rc = device_register(&ap_dev->device); if (rc) { + spin_lock_bh(&ap_dev->lock); + list_del_init(&ap_dev->list); + spin_unlock_bh(&ap_dev->lock); put_device(&ap_dev->device); continue; } /* Add device attributes. */ rc = sysfs_create_group(&ap_dev->device.kobj, &ap_dev_attr_group); - if (!rc) { - spin_lock_bh(&ap_dev->lock); - ap_dev->unregistered = 0; - spin_unlock_bh(&ap_dev->lock); - } - else + if (rc) { device_unregister(&ap_dev->device); + continue; + } } out: mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ); @@ -1496,377 +1802,6 @@ static void ap_config_timeout(unsigned long ptr) queue_work(ap_work_queue, &ap_config_work); } -/** - * ap_poll_read(): Receive pending reply messages from an AP device. - * @ap_dev: pointer to the AP device - * @flags: pointer to control flags, bit 2^0 is set if another poll is - * required, bit 2^1 is set if the poll timer needs to get armed - * - * Returns 0 if the device is still present, -ENODEV if not. - */ -static int ap_poll_read(struct ap_device *ap_dev, unsigned long *flags) -{ - struct ap_queue_status status; - struct ap_message *ap_msg; - - if (ap_dev->queue_count <= 0) - return 0; - status = __ap_recv(ap_dev->qid, &ap_dev->reply->psmid, - ap_dev->reply->message, ap_dev->reply->length); - switch (status.response_code) { - case AP_RESPONSE_NORMAL: - ap_dev->interrupt = status.int_enabled; - atomic_dec(&ap_poll_requests); - ap_decrease_queue_count(ap_dev); - list_for_each_entry(ap_msg, &ap_dev->pendingq, list) { - if (ap_msg->psmid != ap_dev->reply->psmid) - continue; - list_del_init(&ap_msg->list); - ap_dev->pendingq_count--; - ap_msg->receive(ap_dev, ap_msg, ap_dev->reply); - break; - } - if (ap_dev->queue_count > 0) - *flags |= 1; - break; - case AP_RESPONSE_NO_PENDING_REPLY: - ap_dev->interrupt = status.int_enabled; - if (status.queue_empty) { - /* The card shouldn't forget requests but who knows. */ - atomic_sub(ap_dev->queue_count, &ap_poll_requests); - ap_dev->queue_count = 0; - list_splice_init(&ap_dev->pendingq, &ap_dev->requestq); - ap_dev->requestq_count += ap_dev->pendingq_count; - ap_dev->pendingq_count = 0; - } else - *flags |= 2; - break; - default: - return -ENODEV; - } - return 0; -} - -/** - * ap_poll_write(): Send messages from the request queue to an AP device. - * @ap_dev: pointer to the AP device - * @flags: pointer to control flags, bit 2^0 is set if another poll is - * required, bit 2^1 is set if the poll timer needs to get armed - * - * Returns 0 if the device is still present, -ENODEV if not. - */ -static int ap_poll_write(struct ap_device *ap_dev, unsigned long *flags) -{ - struct ap_queue_status status; - struct ap_message *ap_msg; - - if (ap_dev->requestq_count <= 0 || - (ap_dev->queue_count >= ap_dev->queue_depth) || - (ap_dev->reset == AP_RESET_IN_PROGRESS)) - return 0; - /* Start the next request on the queue. */ - ap_msg = list_entry(ap_dev->requestq.next, struct ap_message, list); - status = __ap_send(ap_dev->qid, ap_msg->psmid, - ap_msg->message, ap_msg->length, ap_msg->special); - switch (status.response_code) { - case AP_RESPONSE_NORMAL: - atomic_inc(&ap_poll_requests); - ap_increase_queue_count(ap_dev); - list_move_tail(&ap_msg->list, &ap_dev->pendingq); - ap_dev->requestq_count--; - ap_dev->pendingq_count++; - if (ap_dev->queue_count < ap_dev->queue_depth && - ap_dev->requestq_count > 0) - *flags |= 1; - *flags |= 2; - break; - case AP_RESPONSE_RESET_IN_PROGRESS: - __ap_schedule_poll_timer(); - case AP_RESPONSE_Q_FULL: - *flags |= 2; - break; - case AP_RESPONSE_MESSAGE_TOO_BIG: - case AP_RESPONSE_REQ_FAC_NOT_INST: - return -EINVAL; - default: - return -ENODEV; - } - return 0; -} - -/** - * ap_poll_queue(): Poll AP device for pending replies and send new messages. - * Check if the queue has a pending reset. In case it's done re-enable - * interrupts, otherwise reschedule the poll_timer for another attempt. - * @ap_dev: pointer to the bus device - * @flags: pointer to control flags, bit 2^0 is set if another poll is - * required, bit 2^1 is set if the poll timer needs to get armed - * - * Poll AP device for pending replies and send new messages. If either - * ap_poll_read or ap_poll_write returns -ENODEV unregister the device. - * Returns 0. - */ -static inline int ap_poll_queue(struct ap_device *ap_dev, unsigned long *flags) -{ - struct ap_queue_status status; - int rc; - - if (ap_dev->reset == AP_RESET_IN_PROGRESS) { - status = ap_test_queue(ap_dev->qid, NULL); - switch (status.response_code) { - case AP_RESPONSE_NORMAL: - ap_dev->reset = AP_RESET_IGNORE; - if (ap_using_interrupts()) { - rc = ap_queue_enable_interruption( - ap_dev, ap_airq.lsi_ptr); - if (!rc) - ap_dev->interrupt = AP_INTR_IN_PROGRESS; - else if (rc == -ENODEV) { - pr_err("Registering adapter interrupts for " - "AP %d failed\n", AP_QID_DEVICE(ap_dev->qid)); - return rc; - } - } - /* fall through */ - case AP_RESPONSE_BUSY: - case AP_RESPONSE_RESET_IN_PROGRESS: - *flags |= AP_POLL_AFTER_TIMEOUT; - break; - case AP_RESPONSE_Q_NOT_AVAIL: - case AP_RESPONSE_DECONFIGURED: - case AP_RESPONSE_CHECKSTOPPED: - return -ENODEV; - default: - break; - } - } - - if ((ap_dev->reset != AP_RESET_IN_PROGRESS) && - (ap_dev->interrupt == AP_INTR_IN_PROGRESS)) { - status = ap_test_queue(ap_dev->qid, NULL); - if (ap_using_interrupts()) { - if (status.int_enabled == 1) - ap_dev->interrupt = AP_INTR_ENABLED; - else - *flags |= AP_POLL_AFTER_TIMEOUT; - } else - ap_dev->interrupt = AP_INTR_DISABLED; - } - - rc = ap_poll_read(ap_dev, flags); - if (rc) - return rc; - return ap_poll_write(ap_dev, flags); -} - -/** - * __ap_queue_message(): Queue a message to a device. - * @ap_dev: pointer to the AP device - * @ap_msg: the message to be queued - * - * Queue a message to a device. Returns 0 if successful. - */ -static int __ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg) -{ - struct ap_queue_status status; - - if (list_empty(&ap_dev->requestq) && - (ap_dev->queue_count < ap_dev->queue_depth) && - (ap_dev->reset != AP_RESET_IN_PROGRESS)) { - status = __ap_send(ap_dev->qid, ap_msg->psmid, - ap_msg->message, ap_msg->length, - ap_msg->special); - switch (status.response_code) { - case AP_RESPONSE_NORMAL: - list_add_tail(&ap_msg->list, &ap_dev->pendingq); - atomic_inc(&ap_poll_requests); - ap_dev->pendingq_count++; - ap_increase_queue_count(ap_dev); - ap_dev->total_request_count++; - break; - case AP_RESPONSE_Q_FULL: - case AP_RESPONSE_RESET_IN_PROGRESS: - list_add_tail(&ap_msg->list, &ap_dev->requestq); - ap_dev->requestq_count++; - ap_dev->total_request_count++; - return -EBUSY; - case AP_RESPONSE_REQ_FAC_NOT_INST: - case AP_RESPONSE_MESSAGE_TOO_BIG: - ap_msg->rc = -EINVAL; - ap_msg->receive(ap_dev, ap_msg, NULL); - return -EINVAL; - default: /* Device is gone. */ - ap_msg->rc = -ENODEV; - ap_msg->receive(ap_dev, ap_msg, NULL); - return -ENODEV; - } - } else { - list_add_tail(&ap_msg->list, &ap_dev->requestq); - ap_dev->requestq_count++; - ap_dev->total_request_count++; - return -EBUSY; - } - ap_schedule_poll_timer(); - return 0; -} - -void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg) -{ - unsigned long flags; - int rc; - - /* For asynchronous message handling a valid receive-callback - * is required. */ - BUG_ON(!ap_msg->receive); - - spin_lock_bh(&ap_dev->lock); - if (!ap_dev->unregistered) { - /* Make room on the queue by polling for finished requests. */ - rc = ap_poll_queue(ap_dev, &flags); - if (!rc) - rc = __ap_queue_message(ap_dev, ap_msg); - if (!rc) - wake_up(&ap_poll_wait); - if (rc == -ENODEV) - ap_dev->unregistered = 1; - } else { - ap_msg->rc = -ENODEV; - ap_msg->receive(ap_dev, ap_msg, NULL); - rc = -ENODEV; - } - spin_unlock_bh(&ap_dev->lock); -} -EXPORT_SYMBOL(ap_queue_message); - -/** - * ap_cancel_message(): Cancel a crypto request. - * @ap_dev: The AP device that has the message queued - * @ap_msg: The message that is to be removed - * - * Cancel a crypto request. This is done by removing the request - * from the device pending or request queue. Note that the - * request stays on the AP queue. When it finishes the message - * reply will be discarded because the psmid can't be found. - */ -void ap_cancel_message(struct ap_device *ap_dev, struct ap_message *ap_msg) -{ - struct ap_message *tmp; - - spin_lock_bh(&ap_dev->lock); - if (!list_empty(&ap_msg->list)) { - list_for_each_entry(tmp, &ap_dev->pendingq, list) - if (tmp->psmid == ap_msg->psmid) { - ap_dev->pendingq_count--; - goto found; - } - ap_dev->requestq_count--; - found: - list_del_init(&ap_msg->list); - } - spin_unlock_bh(&ap_dev->lock); -} -EXPORT_SYMBOL(ap_cancel_message); - -/** - * ap_poll_timeout(): AP receive polling for finished AP requests. - * @unused: Unused pointer. - * - * Schedules the AP tasklet using a high resolution timer. - */ -static enum hrtimer_restart ap_poll_timeout(struct hrtimer *unused) -{ - if (!ap_suspend_flag) - tasklet_schedule(&ap_tasklet); - return HRTIMER_NORESTART; -} - -/** - * ap_reset(): Reset a not responding AP device. - * @ap_dev: Pointer to the AP device - * - * Reset a not responding AP device and move all requests from the - * pending queue to the request queue. - */ -static void ap_reset(struct ap_device *ap_dev, unsigned long *flags) -{ - int rc; - - atomic_sub(ap_dev->queue_count, &ap_poll_requests); - ap_dev->queue_count = 0; - list_splice_init(&ap_dev->pendingq, &ap_dev->requestq); - ap_dev->requestq_count += ap_dev->pendingq_count; - ap_dev->pendingq_count = 0; - rc = ap_init_queue(ap_dev); - if (rc == -ENODEV) - ap_dev->unregistered = 1; - else - *flags |= AP_POLL_AFTER_TIMEOUT; -} - -static int __ap_poll_device(struct ap_device *ap_dev, unsigned long *flags) -{ - if (!ap_dev->unregistered) { - if (ap_poll_queue(ap_dev, flags)) - ap_dev->unregistered = 1; - if (ap_dev->reset == AP_RESET_DO) - ap_reset(ap_dev, flags); - } - return 0; -} - -/** - * ap_poll_all(): Poll all AP devices. - * @dummy: Unused variable - * - * Poll all AP devices on the bus in a round robin fashion. Continue - * polling until bit 2^0 of the control flags is not set. If bit 2^1 - * of the control flags has been set arm the poll timer. - */ -static void ap_poll_all(unsigned long dummy) -{ - unsigned long flags; - struct ap_device *ap_dev; - - /* Reset the indicator if interrupts are used. Thus new interrupts can - * be received. Doing it in the beginning of the tasklet is therefor - * important that no requests on any AP get lost. - */ - if (ap_using_interrupts()) - xchg(ap_airq.lsi_ptr, 0); - do { - flags = 0; - spin_lock(&ap_device_list_lock); - list_for_each_entry(ap_dev, &ap_device_list, list) { - spin_lock(&ap_dev->lock); - __ap_poll_device(ap_dev, &flags); - spin_unlock(&ap_dev->lock); - } - spin_unlock(&ap_device_list_lock); - } while (flags & AP_POLL_IMMEDIATELY); - if (flags & AP_POLL_AFTER_TIMEOUT) - __ap_schedule_poll_timer(); -} - -/** - * ap_request_timeout(): Handling of request timeouts - * @data: Holds the AP device. - * - * Handles request timeouts. - */ -static void ap_request_timeout(unsigned long data) -{ - struct ap_device *ap_dev = (struct ap_device *) data; - - if (ap_suspend_flag) - return; - if (ap_dev->reset == AP_RESET_ARMED) { - ap_dev->reset = AP_RESET_DO; - - if (ap_using_interrupts()) - tasklet_schedule(&ap_tasklet); - } -} - static void ap_reset_domain(void) { int i; @@ -1958,14 +1893,11 @@ int __init ap_module_init(void) goto out_root; } - if (ap_select_domain() == 0) - ap_scan_bus(NULL); - /* Setup the AP bus rescan timer. */ setup_timer(&ap_config_timer, ap_config_timeout, 0); - add_timer(&ap_config_timer); - /* Setup the high resultion poll timer. + /* + * Setup the high resultion poll timer. * If we are running under z/VM adjust polling to z/VM polling rate. */ if (MACHINE_IS_VM) @@ -1985,12 +1917,13 @@ int __init ap_module_init(void) if (rc) goto out_pm; + queue_work(ap_work_queue, &ap_config_work); + return 0; out_pm: ap_poll_thread_stop(); out_work: - del_timer_sync(&ap_config_timer); hrtimer_cancel(&ap_poll_timer); destroy_workqueue(ap_work_queue); out_root: diff --git a/drivers/s390/crypto/ap_bus.h b/drivers/s390/crypto/ap_bus.h index af9b705976bc..6adcbdf225d1 100644 --- a/drivers/s390/crypto/ap_bus.h +++ b/drivers/s390/crypto/ap_bus.h @@ -36,9 +36,6 @@ #define AP_CONFIG_TIME 30 /* Time in seconds between AP bus rescans. */ #define AP_POLL_TIME 1 /* Time in ticks between receive polls. */ -#define AP_POLL_IMMEDIATELY 1 /* continue running poll tasklet */ -#define AP_POLL_AFTER_TIMEOUT 2 /* run poll tasklet again after timout */ - extern int ap_domain_index; /** @@ -119,20 +116,46 @@ static inline int ap_test_bit(unsigned int *ptr, unsigned int nr) #define AP_FUNC_EP11 5 #define AP_FUNC_APXA 6 -/* - * AP reset flag states - */ -#define AP_RESET_IGNORE 0 /* request timeout will be ignored */ -#define AP_RESET_ARMED 1 /* request timeout timer is active */ -#define AP_RESET_DO 2 /* AP reset required */ -#define AP_RESET_IN_PROGRESS 3 /* AP reset in progress */ - /* * AP interrupt states */ #define AP_INTR_DISABLED 0 /* AP interrupt disabled */ #define AP_INTR_ENABLED 1 /* AP interrupt enabled */ -#define AP_INTR_IN_PROGRESS 3 /* AP interrupt in progress */ + +/* + * AP device states + */ +enum ap_state { + AP_STATE_RESET_START, + AP_STATE_RESET_WAIT, + AP_STATE_SETIRQ_WAIT, + AP_STATE_IDLE, + AP_STATE_WORKING, + AP_STATE_QUEUE_FULL, + AP_STATE_SUSPEND_WAIT, + AP_STATE_BORKED, + NR_AP_STATES +}; + +/* + * AP device events + */ +enum ap_event { + AP_EVENT_POLL, + AP_EVENT_TIMEOUT, + NR_AP_EVENTS +}; + +/* + * AP wait behaviour + */ +enum ap_wait { + AP_WAIT_AGAIN, /* retry immediately */ + AP_WAIT_TIMEOUT, /* wait for timeout */ + AP_WAIT_INTERRUPT, /* wait for thin interrupt (if available) */ + AP_WAIT_NONE, /* no wait */ + NR_AP_WAIT +}; struct ap_device; struct ap_message; @@ -151,20 +174,22 @@ struct ap_driver { int ap_driver_register(struct ap_driver *, struct module *, char *); void ap_driver_unregister(struct ap_driver *); +typedef enum ap_wait (ap_func_t)(struct ap_device *ap_dev); + struct ap_device { struct device device; struct ap_driver *drv; /* Pointer to AP device driver. */ spinlock_t lock; /* Per device lock. */ struct list_head list; /* private list of all AP devices. */ + enum ap_state state; /* State of the AP device. */ + ap_qid_t qid; /* AP queue id. */ int queue_depth; /* AP queue depth.*/ int device_type; /* AP device type. */ int raw_hwtype; /* AP raw hardware type. */ unsigned int functions; /* AP device function bitfield. */ - int unregistered; /* marks AP device as unregistered */ struct timer_list timeout; /* Timer for request timeouts. */ - int reset; /* Reset required after req. timeout. */ int interrupt; /* indicate if interrupts are enabled */ int queue_count; /* # messages currently on AP queue. */ -- 2.20.1