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path: root/drivers/s390/char/sclp.c
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Diffstat (limited to 'drivers/s390/char/sclp.c')
-rw-r--r--drivers/s390/char/sclp.c90
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;