diff options
Diffstat (limited to 'drivers/s390/char/sclp.c')
| -rw-r--r-- | drivers/s390/char/sclp.c | 90 |
1 files changed, 86 insertions, 4 deletions
diff --git a/drivers/s390/char/sclp.c b/drivers/s390/char/sclp.c index 1fe2643..c316051 100644 --- a/drivers/s390/char/sclp.c +++ b/drivers/s390/char/sclp.c @@ -91,6 +91,9 @@ static struct sclp_req sclp_suspend_req; /* Timer for request retries. */ static struct timer_list sclp_request_timer; +/* Timer for queued requests. */ +static struct timer_list sclp_queue_timer; + /* Internal state: is the driver initialized? */ static volatile enum sclp_init_state_t { sclp_init_state_uninitialized, @@ -215,6 +218,76 @@ sclp_request_timeout(unsigned long data) sclp_process_queue(); } +/* + * Returns the expire value in jiffies of the next pending request timeout, + * if any. Needs to be called with sclp_lock. + */ +static unsigned long __sclp_req_queue_find_next_timeout(void) +{ + unsigned long expires_next = 0; + struct sclp_req *req; + + list_for_each_entry(req, &sclp_req_queue, list) { + if (!req->queue_expires) + continue; + if (!expires_next || + (time_before(req->queue_expires, expires_next))) + expires_next = req->queue_expires; + } + return expires_next; +} + +/* + * Returns expired request, if any, and removes it from the list. + */ +static struct sclp_req *__sclp_req_queue_remove_expired_req(void) +{ + unsigned long flags, now; + struct sclp_req *req; + + spin_lock_irqsave(&sclp_lock, flags); + now = jiffies; + /* Don't need list_for_each_safe because we break out after list_del */ + list_for_each_entry(req, &sclp_req_queue, list) { + if (!req->queue_expires) + continue; + if (time_before_eq(req->queue_expires, now)) { + if (req->status == SCLP_REQ_QUEUED) { + req->status = SCLP_REQ_QUEUED_TIMEOUT; + list_del(&req->list); + goto out; + } + } + } + req = NULL; +out: + spin_unlock_irqrestore(&sclp_lock, flags); + return req; +} + +/* + * Timeout handler for queued requests. Removes request from list and + * invokes callback. This timer can be set per request in situations where + * waiting too long would be harmful to the system, e.g. during SE reboot. + */ +static void sclp_req_queue_timeout(unsigned long data) +{ + unsigned long flags, expires_next; + struct sclp_req *req; + + do { + req = __sclp_req_queue_remove_expired_req(); + if (req && req->callback) + req->callback(req, req->callback_data); + } while (req); + + spin_lock_irqsave(&sclp_lock, flags); + expires_next = __sclp_req_queue_find_next_timeout(); + if (expires_next) + mod_timer(&sclp_queue_timer, expires_next); + spin_unlock_irqrestore(&sclp_lock, flags); +} + /* Try to start a request. Return zero if the request was successfully * started or if it will be started at a later time. Return non-zero otherwise. * Called while sclp_lock is locked. */ @@ -317,6 +390,13 @@ sclp_add_request(struct sclp_req *req) req->start_count = 0; list_add_tail(&req->list, &sclp_req_queue); rc = 0; + if (req->queue_timeout) { + req->queue_expires = jiffies + req->queue_timeout * HZ; + if (!timer_pending(&sclp_queue_timer) || + time_after(sclp_queue_timer.expires, req->queue_expires)) + mod_timer(&sclp_queue_timer, req->queue_expires); + } else + req->queue_expires = 0; /* Start if request is first in list */ if (sclp_running_state == sclp_running_state_idle && req->list.prev == &sclp_req_queue) { @@ -892,7 +972,7 @@ sclp_check_interface(void) spin_lock_irqsave(&sclp_lock, flags); /* Prepare init mask command */ - rc = register_external_interrupt(0x2401, sclp_check_handler); + rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler); if (rc) { spin_unlock_irqrestore(&sclp_lock, flags); return rc; @@ -925,7 +1005,7 @@ sclp_check_interface(void) } else rc = -EBUSY; } - unregister_external_interrupt(0x2401, sclp_check_handler); + unregister_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler); spin_unlock_irqrestore(&sclp_lock, flags); return rc; } @@ -1113,6 +1193,8 @@ sclp_init(void) INIT_LIST_HEAD(&sclp_reg_list); list_add(&sclp_state_change_event.list, &sclp_reg_list); init_timer(&sclp_request_timer); + init_timer(&sclp_queue_timer); + sclp_queue_timer.function = sclp_req_queue_timeout; /* Check interface */ spin_unlock_irqrestore(&sclp_lock, flags); rc = sclp_check_interface(); @@ -1124,7 +1206,7 @@ sclp_init(void) if (rc) goto fail_init_state_uninitialized; /* Register interrupt handler */ - rc = register_external_interrupt(0x2401, sclp_interrupt_handler); + rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_interrupt_handler); if (rc) goto fail_unregister_reboot_notifier; sclp_init_state = sclp_init_state_initialized; @@ -1170,7 +1252,7 @@ static __init int sclp_initcall(void) return rc; sclp_pdev = platform_device_register_simple("sclp", -1, NULL, 0); - rc = PTR_RET(sclp_pdev); + rc = PTR_ERR_OR_ZERO(sclp_pdev); if (rc) goto fail_platform_driver_unregister; |