Re: [PATCH 6/7] scsi: pm8001: use dev_and_phy_addr_same() instead of open coded

From: Jason Yan
Date: Fri Sep 23 2022 - 06:13:56 EST



On 2022/9/23 18:00, John Garry wrote:
On 23/09/2022 10:44, Jason Yan wrote:
          for (phy_id = 0; phy_id < parent_dev->ex_dev.num_phys;

This code seems the same between many libsas LLDDs - could we factor it out into libsas? If so, then maybe those new helpers could be put in sas_internal.h

For the part of putting helpers in sas_internal.h, this needs to make the helpers exported.

Please explain why.

I would assume that if those helpers were only used in libsas code (and not LLDDs) then they could be put in sas_internal.h and no need for export



Sorry, I did not make it clear. I mean we need to export sas_find_attathed_phy() below. Not the sas address comparation helpers.



I think it's not worth to do this because they are very small. I'd still like to make them inline functions in libsas.h such as:


diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
index 2dbead74a2af..e9e76c898287 100644
--- a/include/scsi/libsas.h
+++ b/include/scsi/libsas.h
@@ -648,6 +648,22 @@ static inline bool sas_is_internal_abort(struct sas_task *task)
         return task->task_proto == SAS_PROTOCOL_INTERNAL_ABORT;
  }

+static inline int sas_find_attathed_phy(struct expander_device *ex_dev,
+                                       struct domain_device *dev)
+{
+       struct ex_phy *phy;
+       int phy_id;
+
+       for (phy_id = 0; phy_id < ex_dev->num_phys; phy_id++) {
+               phy = &ex_dev->ex_phy[phy_id];
+               if (SAS_ADDR(phy->attached_sas_addr)
+                       == SAS_ADDR(dev->sas_addr))
+                       return phy_id;
+       }
+
+       return ex_dev->num_phys;

I will note that this code does not use your new helpers

+}
+
  struct sas_domain_function_template {
         /* The class calls these to notify the LLDD of an event. */
         void (*lldd_port_formed)(struct asd_sas_phy *);



And the LLDDs change like:


diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c
index 8e3f2f9ddaac..4e7350609b3d 100644
--- a/drivers/scsi/pm8001/pm8001_sas.c
+++ b/drivers/scsi/pm8001/pm8001_sas.c
@@ -645,16 +645,8 @@ static int pm8001_dev_found_notify(struct domain_device *dev)
         pm8001_device->dcompletion = &completion;
         if (parent_dev && dev_is_expander(parent_dev->dev_type)) {
                 int phy_id;
-               struct ex_phy *phy;
-               for (phy_id = 0; phy_id < parent_dev->ex_dev.num_phys;
-               phy_id++) {
-                       phy = &parent_dev->ex_dev.ex_phy[phy_id];
-                       if (SAS_ADDR(phy->attached_sas_addr)
-                               == SAS_ADDR(dev->sas_addr)) {
-                               pm8001_device->attached_phy = phy_id;
-                               break;
-                       }
-               }
+
+               phy_id = sas_find_attathed_phy(&parent_dev->ex_dev, dev);
                 if (phy_id == parent_dev->ex_dev.num_phys) {
                         pm8001_dbg(pm8001_ha, FAIL,
                                    "Error: no attached dev:%016llx at ex:%016llx.\n",
@@ -662,6 +654,7 @@ static int pm8001_dev_found_notify(struct domain_device *dev)
                                    SAS_ADDR(parent_dev->sas_addr));
                         res = -1;
                 }
+               pm8001_device->attached_phy = phy_id;
         } else {
                 if (dev->dev_type == SAS_SATA_DEV) {
                         pm8001_device->attached_phy =


So I wonder if you have any reasons to insist exporting the helper
Thanks,
John
.