[PATCH 06/17] ublk: don't dereference ublk_queue in ublk_check_and_get_req()

[Caleb Sander Mateos <csander@purestorage.com>]

For ublk servers with many ublk queues, accessing the ublk_queue in
ublk_ch_{read,write}_iter() is a frequent cache miss. Get the flags and
queue depth from the ublk_device instead, which is accessed just before.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
---
 drivers/block/ublk_drv.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 58f688eac742..d6d8dcb72e4b 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -2525,14 +2525,14 @@ static struct request *ublk_check_and_get_req(struct kiocb *iocb,
 
 	if (q_id >= ub->dev_info.nr_hw_queues)
 		return ERR_PTR(-EINVAL);
 
 	ubq = ublk_get_queue(ub, q_id);
-	if (!ublk_support_user_copy(ubq))
+	if (!ublk_dev_support_user_copy(ub))
 		return ERR_PTR(-EACCES);
 
-	if (tag >= ubq->q_depth)
+	if (tag >= ub->dev_info.queue_depth)
 		return ERR_PTR(-EINVAL);
 
 	*io = &ubq->ios[tag];
 	req = __ublk_check_and_get_req(ub, ubq, *io, buf_off);
 	if (!req)
-- 
2.45.2