These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / s390 / block / dasd.c

diff --git a/kernel/drivers/s390/block/dasd.c b/kernel/drivers/s390/block/dasd.c
index 57fd663..4abfbdb 100644 (file)
--- a/kernel/drivers/s390/block/dasd.c
+++ b/kernel/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
  */
@@ -1860,6 +1862,33 @@ 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);
@@ -3006,6 +3030,8 @@ static void dasd_setup_queue(struct dasd_block *block)
        } else {
                max = block->base->discipline->max_blocks << block->s2b_shift;
        }
+       queue_flag_set_unlocked(QUEUE_FLAG_NONROT, block->request_queue);
+       block->request_queue->limits.max_dev_sectors = max;
        blk_queue_logical_block_size(block->request_queue,
                                     block->bp_block);
        blk_queue_max_hw_sectors(block->request_queue, max);
@@ -3300,6 +3326,21 @@ 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);