[SCSI] iscsi: fixup set/get param functions

Reduce duplication in the software iscsi_transport modules by
adding a libiscsi function to handle the common grunt work.

This also has the drivers return specifc -EXXX values for different
errors so userspace can finally handle them in a sane way.

Also just pass the sysfs buffers to the drivers so HW iscsi can
get/set its string values, like targetname, and initiatorname.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

2 files changed, 23 insertions, 21 deletions

diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index cbf7e58bd6f9..ba2760802ded 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -157,6 +157,11 @@ struct iscsi_conn {
         int                     max_xmit_dlength; /* target_max_recv_dsl */
         int                     hdrdgst_en;
         int                     datadgst_en;
+        int                     ifmarker_en;
+        int                     ofmarker_en;
+        /* values userspace uses to id a conn */
+        int                     persistent_port;
+        char                    *persistent_address;
 
         /* MIB-statistics */
         uint64_t                txdata_octets;
@@ -196,8 +201,8 @@ struct iscsi_session {
         int                     pdu_inorder_en;
         int                     dataseq_inorder_en;
         int                     erl;
-        int                     ifmarker_en;
-        int                     ofmarker_en;
+        int                     tpgt;
+        char                    *targetname;
 
         /* control data */
         struct iscsi_transport  *tt;
@@ -240,6 +245,10 @@ iscsi_session_setup(struct iscsi_transport *, struct scsi_transport_template *,
 extern void iscsi_session_teardown(struct iscsi_cls_session *);
 extern struct iscsi_session *class_to_transport_session(struct iscsi_cls_session *);
 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
+extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
+                           enum iscsi_param param, char *buf, int buflen);
+extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
+                                   enum iscsi_param param, char *buf);
 
 #define session_to_cls(_sess) \
         hostdata_session(_sess->host->hostdata)
@@ -255,6 +264,8 @@ extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
                            int);
 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
+extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
+                                enum iscsi_param param, char *buf);
 
 /*
  * pdu and task processing
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index b95151aec602..05397058a9b8 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -34,6 +34,7 @@ struct iscsi_cls_conn;
 struct iscsi_conn;
 struct iscsi_cmd_task;
 struct iscsi_mgmt_task;
+struct sockaddr;
 
 /**
  * struct iscsi_transport - iSCSI Transport template
@@ -46,7 +47,12 @@ struct iscsi_mgmt_task;
  * @bind_conn:          associate this connection with existing iSCSI session
  *                      and specified transport descriptor
  * @destroy_conn:       destroy inactive iSCSI connection
- * @set_param:          set iSCSI Data-Path operational parameter
+ * @set_param:          set iSCSI parameter. Return 0 on success, -ENODATA
+ *                      when param is not supported, and a -Exx value on other
+ *                      error.
+ * @get_param           get iSCSI parameter. Must return number of bytes
+ *                      copied to buffer on success, -ENODATA when param
+ *                      is not supported, and a -Exx value on other error
  * @start_conn:         set connection to be operational
  * @stop_conn:          suspend/recover/terminate connection
  * @send_pdu:           send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
@@ -97,15 +103,11 @@ struct iscsi_transport {
         void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
         void (*destroy_conn) (struct iscsi_cls_conn *conn);
         int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
-                          uint32_t value);
+                          char *buf, int buflen);
         int (*get_conn_param) (struct iscsi_cls_conn *conn,
-                               enum iscsi_param param, uint32_t *value);
+                               enum iscsi_param param, char *buf);
         int (*get_session_param) (struct iscsi_cls_session *session,
-                                  enum iscsi_param param, uint32_t *value);
-        int (*get_conn_str_param) (struct iscsi_cls_conn *conn,
-                                   enum iscsi_param param, char *buf);
-        int (*get_session_str_param) (struct iscsi_cls_session *session,
-                                      enum iscsi_param param, char *buf);
+                                  enum iscsi_param param, char *buf);
         int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
                          char *data, uint32_t data_size);
         void (*get_stats) (struct iscsi_cls_conn *conn,
@@ -157,13 +159,6 @@ struct iscsi_cls_conn {
         struct iscsi_transport *transport;
         uint32_t cid;                   /* connection id */
 
-        /* portal/group values we got during discovery */
-        char *persistent_address;
-        int persistent_port;
-        /* portal/group values we are currently using */
-        char *address;
-        int port;
-
         int active;                     /* must be accessed with the connlock */
         struct device dev;              /* sysfs transport/container device */
         struct mempool_zone *z_error;
@@ -187,10 +182,6 @@ struct iscsi_cls_session {
         struct list_head host_list;
         struct iscsi_transport *transport;
 
-        /* iSCSI values used as unique id by userspace. */
-        char *targetname;
-        int tpgt;
-
         /* recovery fields */
         int recovery_tmo;
         struct work_struct recovery_work;