[PATCH 4.14 140/211] scsi: mpt3sas: Fix Sync cache command failure during driver unload

From: Greg Kroah-Hartman
Date: Wed Nov 27 2019 - 15:53:27 EST


From: Suganath Prabu <suganath-prabu.subramani@xxxxxxxxxxxx>

[ Upstream commit 9029a72500b95578a35877a43473b82cb0386c53 ]

This is to fix SYNC CACHE and START STOP command failures with
DID_NO_CONNECT during driver unload.

In driver's IO submission patch (i.e. in driver's .queuecommand()) driver
won't allow any SCSI commands to the IOC when ioc->remove_host flag is set
and hence SYNC CACHE commands which are issued to the target drives (where
write cache is enabled) during driver unload time is failed with
DID_NO_CONNECT status.

Now modified the driver to allow SYNC CACHE and START STOP commands to IOC,
even when remove_host flag is set.

Signed-off-by: Suganath Prabu <suganath-prabu.subramani@xxxxxxxxxxxx>
Reviewed-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/scsi/mpt3sas/mpt3sas_scsih.c | 36 +++++++++++++++++++++++++++-
1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
index b28efddab7b1a..9ef0c6265cd2b 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -3328,6 +3328,40 @@ _scsih_tm_tr_complete(struct MPT3SAS_ADAPTER *ioc, u16 smid, u8 msix_index,
return _scsih_check_for_pending_tm(ioc, smid);
}

+/** _scsih_allow_scmd_to_device - check whether scmd needs to
+ * issue to IOC or not.
+ * @ioc: per adapter object
+ * @scmd: pointer to scsi command object
+ *
+ * Returns true if scmd can be issued to IOC otherwise returns false.
+ */
+inline bool _scsih_allow_scmd_to_device(struct MPT3SAS_ADAPTER *ioc,
+ struct scsi_cmnd *scmd)
+{
+
+ if (ioc->pci_error_recovery)
+ return false;
+
+ if (ioc->hba_mpi_version_belonged == MPI2_VERSION) {
+ if (ioc->remove_host)
+ return false;
+
+ return true;
+ }
+
+ if (ioc->remove_host) {
+
+ switch (scmd->cmnd[0]) {
+ case SYNCHRONIZE_CACHE:
+ case START_STOP:
+ return true;
+ default:
+ return false;
+ }
+ }
+
+ return true;
+}

/**
* _scsih_sas_control_complete - completion routine
@@ -4100,7 +4134,7 @@ scsih_qcmd(struct Scsi_Host *shost, struct scsi_cmnd *scmd)
return 0;
}

- if (ioc->pci_error_recovery || ioc->remove_host) {
+ if (!(_scsih_allow_scmd_to_device(ioc, scmd))) {
scmd->result = DID_NO_CONNECT << 16;
scmd->scsi_done(scmd);
return 0;
--
2.20.1