On 06/28/2017 10:32 AM, Hannes Reinecke wrote:
zfcp_task_mgmt_function() is only used for lun and device reset,
so it should be using the scsi device as an argument, not the
scsi command.

Signed-off-by: Hannes Reinecke <h...@suse.com>
---
  drivers/s390/scsi/zfcp_ext.h  |  2 +-
  drivers/s390/scsi/zfcp_fc.h   |  9 +--------
  drivers/s390/scsi/zfcp_fsf.c  | 21 +++++++++++----------
  drivers/s390/scsi/zfcp_scsi.c | 12 ++++++------
  4 files changed, 19 insertions(+), 25 deletions(-)

diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h
index 57f1d4a..64d4db7 100644
--- a/drivers/s390/scsi/zfcp_ext.h
+++ b/drivers/s390/scsi/zfcp_ext.h
@@ -117,7 +117,7 @@ extern int zfcp_fsf_send_els(struct zfcp_adapter *, u32,
                             struct zfcp_fsf_ct_els *, unsigned int);
  extern int zfcp_fsf_fcp_cmnd(struct scsi_cmnd *);
  extern void zfcp_fsf_req_free(struct zfcp_fsf_req *);
-extern struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_cmnd *, u8);
+extern struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_device *, u8);
  extern struct zfcp_fsf_req *zfcp_fsf_abort_fcp_cmnd(struct scsi_cmnd *);
  extern void zfcp_fsf_reqid_check(struct zfcp_qdio *, int);

diff --git a/drivers/s390/scsi/zfcp_fc.h b/drivers/s390/scsi/zfcp_fc.h
index df2b541..f08eaf9 100644
--- a/drivers/s390/scsi/zfcp_fc.h
+++ b/drivers/s390/scsi/zfcp_fc.h
@@ -206,19 +206,12 @@ struct zfcp_fc_wka_ports {
   * zfcp_fc_scsi_to_fcp - setup FCP command with data from scsi_cmnd
   * @fcp: fcp_cmnd to setup
   * @scsi: scsi_cmnd where to get LUN, task attributes/flags and CDB
- * @tm: task management flags to setup task management command
   */
  static inline
-void zfcp_fc_scsi_to_fcp(struct fcp_cmnd *fcp, struct scsi_cmnd *scsi,
-                        u8 tm_flags)
+void zfcp_fc_scsi_to_fcp(struct fcp_cmnd *fcp, struct scsi_cmnd *scsi)
  {
        int_to_scsilun(scsi->device->lun, (struct scsi_lun *) &fcp->fc_lun);

-       if (unlikely(tm_flags)) {
-               fcp->fc_tm_flags = tm_flags;
-               return;
-       }
-
        fcp->fc_pri_ta = FCP_PTA_SIMPLE;

        if (scsi->sc_data_direction == DMA_FROM_DEVICE)

When I wrote my zfcp decoupling patch series I did a lot of git history research in order to double check if my changes are OK.

Here, I figured that I'd like to separately revert commit 2443c8b23aea ("[SCSI] zfcp: Merge FCP task management setup with regular FCP command setup"), because this introduced a dependency on the unsuitable SCSI command for scsi_eh / TMF. Even though it was one of the first commits I posted upstream as newbie zfcp maintainer... little did I know.

diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index 27ff38f..c4bd3d4 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -2036,10 +2036,9 @@ static void zfcp_fsf_req_trace(struct zfcp_fsf_req *req, 
struct scsi_cmnd *scsi)

-static void zfcp_fsf_fcp_handler_common(struct zfcp_fsf_req *req)
+static void zfcp_fsf_fcp_handler_common(struct zfcp_fsf_req *req,
+                                       struct scsi_device *sdev)


@@ -2120,7 +2119,7 @@ static void zfcp_fsf_fcp_cmnd_handler(struct zfcp_fsf_req 
*req)

-       zfcp_fsf_fcp_handler_common(req);
+       zfcp_fsf_fcp_handler_common(req, scpnt->device);

@@ -2296,8 +2295,9 @@ static void zfcp_fsf_fcp_task_mgmt_handler(struct 
zfcp_fsf_req *req)
  {

+       struct scsi_device *sdev = req->data;

-       zfcp_fsf_fcp_handler_common(req);
+       zfcp_fsf_fcp_handler_common(req, sdev);

Moving the resolving of req->data into the callers of zfcp_fsf_fcp_handler_common() I did the same way in my own patch series.

@@ -2313,12 +2313,12 @@ static void zfcp_fsf_fcp_task_mgmt_handler(struct 
zfcp_fsf_req *req)

-struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_cmnd *scmnd,
+struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_device *sdev,
                                            u8 tm_flags)

@@ -2338,7 +2338,7 @@ struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct 
scsi_cmnd *scmnd,

-       req->data = scmnd;
+       req->data = sdev;

diff --git a/drivers/s390/scsi/zfcp_scsi.c b/drivers/s390/scsi/zfcp_scsi.c
index 5fada93..dd7bea0 100644
--- a/drivers/s390/scsi/zfcp_scsi.c
+++ b/drivers/s390/scsi/zfcp_scsi.c
@@ -259,17 +259,17 @@ static void zfcp_scsi_forget_cmnds(struct zfcp_scsi_dev 
*zsdev, u8 tm_flags)

-static int zfcp_task_mgmt_function(struct scsi_cmnd *scpnt, u8 tm_flags)
+static int zfcp_task_mgmt_function(struct scsi_device *sdev, u8 tm_flags)
  {
-       struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
+       struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
        struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
-       struct fc_port *rport = zfcp_sdev->port->rport;

This smells very odd: fc_port instead of fc_*r*port.
Looks like this was introduced buggy in "[PATCH 15/47] scsi_transport_fc: Use fc_rport as argument for fc_block_scsi_eh" and should be avoided for bisectability.

+       struct fc_rport *rport = zfcp_sdev->port->rport;

-               fsf_req = zfcp_fsf_fcp_task_mgmt(scpnt, tm_flags);
+               fsf_req = zfcp_fsf_fcp_task_mgmt(sdev, tm_flags);

  static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
  {
-       return zfcp_task_mgmt_function(scpnt, FCP_TMF_LUN_RESET);
+       return zfcp_task_mgmt_function(scpnt->device, FCP_TMF_LUN_RESET);
  }

  static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *scpnt)
  {
-       return zfcp_task_mgmt_function(scpnt, FCP_TMF_TGT_RESET);
+       return zfcp_task_mgmt_function(scpnt->device, FCP_TMF_TGT_RESET);
  }

Won't the target_reset_handler eventually have scsi_target as argument and thus we will not have any particular scsi_device to pass anymore later in the patch set?

In my patch series, I replaced scsi_cmnd with a mandatory zfcp_port and an optional(!) scsi_device for the TMF call chains in zfcp. I thought scsi_device must be optional because it only exists for LUN reset but not for target reset.
Does this make sense?

--
Mit freundlichen Grüßen / Kind regards
Steffen Maier

Linux on z Systems Development

IBM Deutschland Research & Development GmbH
Vorsitzende des Aufsichtsrats: Martina Koederitz
Geschaeftsfuehrung: Dirk Wittkopp
Sitz der Gesellschaft: Boeblingen
Registergericht: Amtsgericht Stuttgart, HRB 243294

Reply via email to