[PATCH 5.4.y] s390/dasd: add missing discipline function

["Jan Höppner" <hoeppner@linux.ibm.com>]

From: Stefan Haberland <sth@linux.ibm.com>

Fix crash with illegal operation exception in dasd_device_tasklet.
Commit b72949328869 ("s390/dasd: Prepare for additional path event handling")
renamed the verify_path function for ECKD but not for FBA and DIAG.
This leads to a panic when the path verification function is called for a
FBA or DIAG device.

Fix by defining a wrapper function for dasd_generic_verify_path().

Fixes: b72949328869 ("s390/dasd: Prepare for additional path event handling")
Cc: <stable@vger.kernel.org> #5.11
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20210525125006.157531-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/s390/block/dasd_diag.c | 7 ++++++-
 drivers/s390/block/dasd_fba.c  | 7 ++++++-
 drivers/s390/block/dasd_int.h  | 1 -
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c
index f7ae03fd36cb..f029884eabd1 100644
--- a/drivers/s390/block/dasd_diag.c
+++ b/drivers/s390/block/dasd_diag.c
@@ -644,12 +644,17 @@ static void dasd_diag_setup_blk_queue(struct dasd_block *block)
 	blk_queue_segment_boundary(q, PAGE_SIZE - 1);
 }
 
+static int dasd_diag_pe_handler(struct dasd_device *device, __u8 tbvpm)
+{
+	return dasd_generic_verify_path(device, tbvpm);
+}
+
 static struct dasd_discipline dasd_diag_discipline = {
 	.owner = THIS_MODULE,
 	.name = "DIAG",
 	.ebcname = "DIAG",
 	.check_device = dasd_diag_check_device,
-	.verify_path = dasd_generic_verify_path,
+	.pe_handler = dasd_diag_pe_handler,
 	.fill_geometry = dasd_diag_fill_geometry,
 	.setup_blk_queue = dasd_diag_setup_blk_queue,
 	.start_IO = dasd_start_diag,
diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c
index 1a44e321b54e..b159575a2760 100644
--- a/drivers/s390/block/dasd_fba.c
+++ b/drivers/s390/block/dasd_fba.c
@@ -803,13 +803,18 @@ static void dasd_fba_setup_blk_queue(struct dasd_block *block)
 	blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
 }
 
+static int dasd_fba_pe_handler(struct dasd_device *device, __u8 tbvpm)
+{
+	return dasd_generic_verify_path(device, tbvpm);
+}
+
 static struct dasd_discipline dasd_fba_discipline = {
 	.owner = THIS_MODULE,
 	.name = "FBA ",
 	.ebcname = "FBA ",
 	.check_device = dasd_fba_check_characteristics,
 	.do_analysis = dasd_fba_do_analysis,
-	.verify_path = dasd_generic_verify_path,
+	.pe_handler = dasd_fba_pe_handler,
 	.setup_blk_queue = dasd_fba_setup_blk_queue,
 	.fill_geometry = dasd_fba_fill_geometry,
 	.start_IO = dasd_start_IO,
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index e8a06d85d6f7..5d7d35ca5eb4 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -298,7 +298,6 @@ struct dasd_discipline {
 	 * e.g. verify that new path is compatible with the current
 	 * configuration.
 	 */
-	int (*verify_path)(struct dasd_device *, __u8);
 	int (*pe_handler)(struct dasd_device *, __u8);
 
 	/*
-- 
2.37.2