[Devel] [PATCH RHEL8 COMMIT] dm: Call io_hints even for device-less drivers

[Konstantin Khorenko]

The commit is pushed to "branch-rh8-4.18.0-240.1.1.vz8.5.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh8-4.18.0-240.1.1.vz8.5.30
------>
commit 6a09c7c0a0b0c098bd442675b375952a34e18111
Author: Kirill Tkhai <ktkhai at virtuozzo.com>
Date:   Mon May 17 19:04:36 2021 +0300

    dm: Call io_hints even for device-less drivers
    
    Ploop wants to set proper discard_granularity
    despite it is not mapped on real device.
    
    Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
    
    =====================
    Patchset description:
    
    dm-ploop: Kill loop
    
    Intermediate patches can't be base for bisect.
    
    In scope of https://jira.sw.ru/browse/PSBM-123654
    
    Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
---
 drivers/md/dm-table.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 3545281e5716..e43e975ea9b4 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1498,8 +1498,11 @@ int dm_calculate_queue_limits(struct dm_table *table,
 
 		ti = dm_table_get_target(table, i);
 
-		if (!ti->type->iterate_devices)
+		if (!ti->type->iterate_devices) {
+			if (ti->type->io_hints)
+				ti->type->io_hints(ti, &ti_limits);
 			goto combine_limits;
+		}
 
 		/*
 		 * Combine queue limits of all the devices this target uses.