s390/zcrypt: Enable request count reset for cards and queues.

This patch introduces the possibility to reset the
request_count attribute for cards and queues to zero.
This can be used to set a clear state on the counters before
running an application and try out if and which hardware is
actually used. If the request_count counter of a card is
reset, for all associated queues the request_count is also
zeroed. If just a queue request_count is reset the card
counter is not updated however.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

2 files changed, 37 insertions, 8 deletions

diff --git a/drivers/s390/crypto/ap_card.c b/drivers/s390/crypto/ap_card.c
index 1cd9128593e4..cfa161ccc74e 100644
--- a/drivers/s390/crypto/ap_card.c
+++ b/drivers/s390/crypto/ap_card.c
@@ -58,9 +58,9 @@ static ssize_t ap_functions_show(struct device *dev,
 
 static DEVICE_ATTR(ap_functions, 0444, ap_functions_show, NULL);
 
-static ssize_t ap_request_count_show(struct device *dev,
-                                     struct device_attribute *attr,
-                                     char *buf)
+static ssize_t ap_req_count_show(struct device *dev,
+                                 struct device_attribute *attr,
+                                 char *buf)
 {
         struct ap_card *ac = to_ap_card(dev);
         unsigned int req_cnt;
@@ -72,7 +72,23 @@ static ssize_t ap_request_count_show(struct device *dev,
         return snprintf(buf, PAGE_SIZE, "%d\n", req_cnt);
 }
 
-static DEVICE_ATTR(request_count, 0444, ap_request_count_show, NULL);
+static ssize_t ap_req_count_store(struct device *dev,
+                                  struct device_attribute *attr,
+                                  const char *buf, size_t count)
+{
+        struct ap_card *ac = to_ap_card(dev);
+        struct ap_queue *aq;
+
+        spin_lock_bh(&ap_list_lock);
+        for_each_ap_queue(aq, ac)
+                aq->total_request_count = 0;
+        spin_unlock_bh(&ap_list_lock);
+        atomic_set(&ac->total_request_count, 0);
+
+        return count;
+}
+
+static DEVICE_ATTR(request_count, 0644, ap_req_count_show, ap_req_count_store);
 
 static ssize_t ap_requestq_count_show(struct device *dev,
                                       struct device_attribute *attr, char *buf)
diff --git a/drivers/s390/crypto/ap_queue.c b/drivers/s390/crypto/ap_queue.c
index 7be67fa9f224..480c58a63769 100644
--- a/drivers/s390/crypto/ap_queue.c
+++ b/drivers/s390/crypto/ap_queue.c
@@ -459,9 +459,9 @@ EXPORT_SYMBOL(ap_queue_resume);
 /*
  * AP queue related attributes.
  */
-static ssize_t ap_request_count_show(struct device *dev,
-                                     struct device_attribute *attr,
-                                     char *buf)
+static ssize_t ap_req_count_show(struct device *dev,
+                                 struct device_attribute *attr,
+                                 char *buf)
 {
         struct ap_queue *aq = to_ap_queue(dev);
         unsigned int req_cnt;
@@ -472,7 +472,20 @@ static ssize_t ap_request_count_show(struct device *dev,
         return snprintf(buf, PAGE_SIZE, "%d\n", req_cnt);
 }
 
-static DEVICE_ATTR(request_count, 0444, ap_request_count_show, NULL);
+static ssize_t ap_req_count_store(struct device *dev,
+                                  struct device_attribute *attr,
+                                  const char *buf, size_t count)
+{
+        struct ap_queue *aq = to_ap_queue(dev);
+
+        spin_lock_bh(&aq->lock);
+        aq->total_request_count = 0;
+        spin_unlock_bh(&aq->lock);
+
+        return count;
+}
+
+static DEVICE_ATTR(request_count, 0644, ap_req_count_show, ap_req_count_store);
 
 static ssize_t ap_requestq_count_show(struct device *dev,
                                       struct device_attribute *attr, char *buf)