drbd: split out a drbd_discard_supported helper

Add a helper to check if discard is supported for a given connection /
backing device combination.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Philipp Reisner <philipp.reisner@linbit.com>
Reviewed-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20240306140332.623759-7-philipp.reisner@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index a79b7fe5335de4763dd537a30b2bde367a081e20..94ed2b3ea6361d48109462438e2bedd993fd0fcf 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1231,24 +1231,33 @@ static unsigned int drbd_max_discard_sectors(struct drbd_connection *connection)
        return AL_EXTENT_SIZE >> 9;
 }
 
-static void decide_on_discard_support(struct drbd_device *device,
+static bool drbd_discard_supported(struct drbd_connection *connection,
                struct drbd_backing_dev *bdev)
 {
-       struct drbd_connection *connection =
-               first_peer_device(device)->connection;
-       struct request_queue *q = device->rq_queue;
-       unsigned int max_discard_sectors;
-
        if (bdev && !bdev_max_discard_sectors(bdev->backing_bdev))
-               goto not_supported;
+               return false;
 
        if (connection->cstate >= C_CONNECTED &&
            !(connection->agreed_features & DRBD_FF_TRIM)) {
                drbd_info(connection,
                        "peer DRBD too old, does not support TRIM: disabling discards\n");
-               goto not_supported;
+               return false;
        }
 
+       return true;
+}
+
+static void decide_on_discard_support(struct drbd_device *device,
+               struct drbd_backing_dev *bdev)
+{
+       struct drbd_connection *connection =
+               first_peer_device(device)->connection;
+       struct request_queue *q = device->rq_queue;
+       unsigned int max_discard_sectors;
+
+       if (!drbd_discard_supported(connection, bdev))
+               goto not_supported;
+
        /*
         * We don't care for the granularity, really.
         *