diff options
| author |   Stefan Haberland <sth@linux.vnet.ibm.com> | 2018-02-07 17:39:14 +0100 |
|---|---|---|
| committer |   Martin Schwidefsky <schwidefsky@de.ibm.com> | 2018-02-19 08:00:06 +0100 |
| commit | 9487cfd3430d07366801886bdf185799a2b6f066 (patch) | |
| tree | fafddcb9486322303475f687d41b30ce6dad7c34 /drivers | |
| parent | Linux 4.16-rc2 (diff) | |
| download | linux-dev-9487cfd3430d07366801886bdf185799a2b6f066.tar.xz linux-dev-9487cfd3430d07366801886bdf185799a2b6f066.zip | |
s390/dasd: fix handling of internal requests
Internal DASD device driver I/O such as query host access count or
path verification is started using the _sleep_on() function.
To mark a request as started or ended the callback_data is set to either
DASD_SLEEPON_START_TAG or DASD_SLEEPON_END_TAG.
In cases where the request has to be stopped unconditionally the status is
set to DASD_SLEEPON_END_TAG as well which leads to immediate clearing of
the request.
But the request might still be on a device request queue for normal
operation which might lead to a panic because of a BUG() statement in
__dasd_device_process_final_queue() or a list corruption of the device
request queue.
Fix by removing the setting of DASD_SLEEPON_END_TAG in the
dasd_cancel_req() and dasd_generic_requeue_all_requests() functions and
ensure that the request is not deleted in the requeue function.
Trigger the device tasklet in the requeue function and let the normal
processing cleanup the request.
Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/s390/block/dasd.c | 21 |
1 files changed, 7 insertions, 14 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index a7c15f0085e2..ecef8e73d40b 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -2581,8 +2581,6 @@ int dasd_cancel_req(struct dasd_ccw_req *cqr) case DASD_CQR_QUEUED: /* request was not started - just set to cleared */ cqr->status = DASD_CQR_CLEARED; - if (cqr->callback_data == DASD_SLEEPON_START_TAG) - cqr->callback_data = DASD_SLEEPON_END_TAG; break; case DASD_CQR_IN_IO: /* request in IO - terminate IO and release again */ @@ -3902,9 +3900,12 @@ static int dasd_generic_requeue_all_requests(struct dasd_device *device) wait_event(dasd_flush_wq, (cqr->status != DASD_CQR_CLEAR_PENDING)); - /* mark sleepon requests as ended */ - if (cqr->callback_data == DASD_SLEEPON_START_TAG) - cqr->callback_data = DASD_SLEEPON_END_TAG; + /* + * requeue requests to blocklayer will only work + * for block device requests + */ + if (_dasd_requeue_request(cqr)) + continue; /* remove requests from device and block queue */ list_del_init(&cqr->devlist); @@ -3917,13 +3918,6 @@ static int dasd_generic_requeue_all_requests(struct dasd_device *device) cqr = refers; } - /* - * requeue requests to blocklayer will only work - * for block device requests - */ - if (_dasd_requeue_request(cqr)) - continue; - if (cqr->block) list_del_init(&cqr->blocklist); cqr->block->base->discipline->free_cp( @@ -3940,8 +3934,7 @@ static int dasd_generic_requeue_all_requests(struct dasd_device *device) list_splice_tail(&requeue_queue, &device->ccw_queue); spin_unlock_irq(get_ccwdev_lock(device->cdev)); } - /* wake up generic waitqueue for eventually ended sleepon requests */ - wake_up(&generic_waitq); + dasd_schedule_device_bh(device); return rc; } |