[PATCH 4.14 043/189] scsi: storvsc: Set up correct queue depth values for IDE devices

Greg Kroah-Hartman
2018-06-18T08:30:56Z

From: Long Li <longli@microsoft.com>

[ Upstream commit f286299c1d0ba5e2ca0377610307b370fe178767 ]

Unlike SCSI and FC, we don't use multiple channels for IDE. Also fix
the calculation for sub-channels.

Signed-off-by: Long Li <longli@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/scsi/storvsc_drv.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1725,11 +1725,14 @@ static int storvsc_probe(struct hv_devic
max_targets = STORVSC_MAX_TARGETS;
max_channels = STORVSC_MAX_CHANNELS;
/*
- * On Windows8 and above, we support sub-channels for storage.
+ * On Windows8 and above, we support sub-channels for storage
+ * on SCSI and FC controllers.
* The number of sub-channels offerred is based on the number of
* VCPUs in the guest.
*/
- max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel);
+ if (!dev_is_ide)
+ max_sub_channels =
+ (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
}

scsi_driver.can_queue = (max_outstanding_req_per_channel *