diff options
| author | Harald Freudenberger <freude@linux.ibm.com> | 2018-11-26 17:50:04 +0300 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2018-12-13 12:42:26 +0300 |
| commit | 42a87d4103ae365e18c3be1333592ab583b8ad9d (patch) | |
| tree | 0ee25e594ab56b2345bc811393e65f9e18f7a0db /drivers/s390 | |
| parent | 98dfd32620e970eb576ebce5ea39d905cb005e72 (diff) | |
| download | linux-42a87d4103ae365e18c3be1333592ab583b8ad9d.tar.xz | |
s390/zcrypt: make sysfs reset attribute trigger queue reset
Until now there is no way to reset a AP queue or card. Driving a card
or queue offline and online again does only toggle the 'software'
online state. The only way to trigger a (hardware) reset is by running
hot-unplug/hot-plug for example on the HMC.
This patch makes the queue reset attribute in sysfs writable.
Writing into this attribute triggers a reset on the AP queue's state
machine. So the AP queue is flushed and state machine runs through the
initial states which cause a reset (PQAP(RAPQ)) and a re-registration
to interrupts (PQAP(AQIC)) if available.
The reset sysfs attribute is writable by root only. So only an
administrator is allowed to initiate a reset of AP queues. Please note
that the queue's counter values are left untouched by the reset.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390')
| -rw-r--r-- | drivers/s390/crypto/ap_queue.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/drivers/s390/crypto/ap_queue.c b/drivers/s390/crypto/ap_queue.c index 0aa4b3ccc948..576ac08777c5 100644 --- a/drivers/s390/crypto/ap_queue.c +++ b/drivers/s390/crypto/ap_queue.c @@ -14,6 +14,9 @@ #include <asm/facility.h> #include "ap_bus.h" +#include "ap_debug.h" + +static void __ap_flush_queue(struct ap_queue *aq); /** * ap_queue_enable_interruption(): Enable interruption on an AP queue. @@ -541,7 +544,25 @@ static ssize_t reset_show(struct device *dev, return rc; } -static DEVICE_ATTR_RO(reset); +static ssize_t reset_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); + __ap_flush_queue(aq); + aq->state = AP_STATE_RESET_START; + ap_wait(ap_sm_event(aq, AP_EVENT_POLL)); + spin_unlock_bh(&aq->lock); + + AP_DBF(DBF_INFO, "reset queue=%02x.%04x triggered by user\n", + AP_QID_CARD(aq->qid), AP_QID_QUEUE(aq->qid)); + + return count; +} + +static DEVICE_ATTR_RW(reset); static ssize_t interrupt_show(struct device *dev, struct device_attribute *attr, char *buf) |