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path: root/drivers/s390/block/dasd.c
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Diffstat (limited to 'drivers/s390/block/dasd.c')
-rw-r--r--drivers/s390/block/dasd.c53
1 files changed, 46 insertions, 7 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 57fd66357..f73d2f579 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -38,6 +38,8 @@
*/
#define DASD_CHANQ_MAX_SIZE 4
+#define DASD_DIAG_MOD "dasd_diag_mod"
+
/*
* SECTION: exported variables of dasd.c
*/
@@ -1861,6 +1863,33 @@ static void __dasd_device_check_expire(struct dasd_device *device)
}
/*
+ * return 1 when device is not eligible for IO
+ */
+static int __dasd_device_is_unusable(struct dasd_device *device,
+ struct dasd_ccw_req *cqr)
+{
+ int mask = ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM);
+
+ if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+ /* dasd is being set offline. */
+ return 1;
+ }
+ if (device->stopped) {
+ if (device->stopped & mask) {
+ /* stopped and CQR will not change that. */
+ return 1;
+ }
+ if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
+ /* CQR is not able to change device to
+ * operational. */
+ return 1;
+ }
+ /* CQR required to get device operational. */
+ }
+ return 0;
+}
+
+/*
* Take a look at the first request on the ccw queue and check
* if it needs to be started.
*/
@@ -1874,13 +1903,8 @@ static void __dasd_device_start_head(struct dasd_device *device)
cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
if (cqr->status != DASD_CQR_QUEUED)
return;
- /* when device is stopped, return request to previous layer
- * exception: only the disconnect or unresumed bits are set and the
- * cqr is a path verification request
- */
- if (device->stopped &&
- !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
- && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) {
+ /* if device is not usable return request to upper layer */
+ if (__dasd_device_is_unusable(device, cqr)) {
cqr->intrc = -EAGAIN;
cqr->status = DASD_CQR_CLEARED;
dasd_schedule_device_bh(device);
@@ -3300,6 +3324,21 @@ int dasd_generic_set_online(struct ccw_device *cdev,
discipline = base_discipline;
if (device->features & DASD_FEATURE_USEDIAG) {
if (!dasd_diag_discipline_pointer) {
+ /* Try to load the required module. */
+ rc = request_module(DASD_DIAG_MOD);
+ if (rc) {
+ pr_warn("%s Setting the DASD online failed "
+ "because the required module %s "
+ "could not be loaded (rc=%d)\n",
+ dev_name(&cdev->dev), DASD_DIAG_MOD,
+ rc);
+ dasd_delete_device(device);
+ return -ENODEV;
+ }
+ }
+ /* Module init could have failed, so check again here after
+ * request_module(). */
+ if (!dasd_diag_discipline_pointer) {
pr_warn("%s Setting the DASD online failed because of missing DIAG discipline\n",
dev_name(&cdev->dev));
dasd_delete_device(device);