scsi: target: Move cmd counter allocation

iSCSI needs to allocate its cmd counter per connection for MCS support
where we need to stop and wait on commands running on a connection instead
of per session. This moves the cmd counter allocation to
target_setup_session() which is used by drivers that need the stop+wait
behavior per session.

xcopy doesn't need stop+wait at all, so we will be OK moving the cmd
counter allocation outside of transport_init_session().

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230319015620.96006-3-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c
index 27e448c..8ab6c01 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_login.c
+++ b/drivers/target/iscsi/iscsi_target_login.c
@@ -324,8 +324,18 @@ static int iscsi_login_zero_tsih_s1(
                goto free_ops;
        }
 
+       /*
+        * This is temp for iser. It will be moved to per conn in later
+        * patches for iscsi.
+        */
+       sess->se_sess->cmd_cnt = target_alloc_cmd_counter();
+       if (!sess->se_sess->cmd_cnt)
+               goto free_se_sess;
+
        return 0;
 
+free_se_sess:
+       transport_free_session(sess->se_sess);
 free_ops:
        kfree(sess->sess_ops);
 free_id:

diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h
index 38a6d08..85e35cf 100644 (file)
--- a/drivers/target/target_core_internal.h
+++ b/drivers/target/target_core_internal.h
@@ -138,7 +138,6 @@ int init_se_kmem_caches(void);
 void   release_se_kmem_caches(void);
 u32    scsi_get_new_index(scsi_index_t);
 void   transport_subsystem_check_init(void);
-void   transport_uninit_session(struct se_session *);
 unsigned char *transport_dump_cmd_direction(struct se_cmd *);
 void   transport_dump_dev_state(struct se_device *, char *, int *);
 void   transport_dump_dev_info(struct se_device *, struct se_lun *,

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 3d6034f..60647a4 100644 (file)
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -228,7 +228,7 @@ static void target_release_cmd_refcnt(struct percpu_ref *ref)
        wake_up(&cmd_cnt->refcnt_wq);
 }
 
-static struct target_cmd_counter *target_alloc_cmd_counter(void)
+struct target_cmd_counter *target_alloc_cmd_counter(void)
 {
        struct target_cmd_counter *cmd_cnt;
        int rc;
@@ -252,6 +252,7 @@ free_cmd_cnt:
        kfree(cmd_cnt);
        return NULL;
 }
+EXPORT_SYMBOL_GPL(target_alloc_cmd_counter);
 
 static void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt)
 {
@@ -271,24 +272,14 @@ static void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt)
  *
  * The caller must have zero-initialized @se_sess before calling this function.
  */
-int transport_init_session(struct se_session *se_sess)
+void transport_init_session(struct se_session *se_sess)
 {
        INIT_LIST_HEAD(&se_sess->sess_list);
        INIT_LIST_HEAD(&se_sess->sess_acl_list);
        spin_lock_init(&se_sess->sess_cmd_lock);
-       se_sess->cmd_cnt = target_alloc_cmd_counter();
-       if (!se_sess->cmd_cnt)
-               return -ENOMEM;
-
-       return  0;
 }
 EXPORT_SYMBOL(transport_init_session);
 
-void transport_uninit_session(struct se_session *se_sess)
-{
-       target_free_cmd_counter(se_sess->cmd_cnt);
-}
-
 /**
  * transport_alloc_session - allocate a session object and initialize it
  * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
@@ -296,7 +287,6 @@ void transport_uninit_session(struct se_session *se_sess)
 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
 {
        struct se_session *se_sess;
-       int ret;
 
        se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
        if (!se_sess) {
@@ -304,11 +294,7 @@ struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
                                " se_sess_cache\n");
                return ERR_PTR(-ENOMEM);
        }
-       ret = transport_init_session(se_sess);
-       if (ret < 0) {
-               kmem_cache_free(se_sess_cache, se_sess);
-               return ERR_PTR(ret);
-       }
+       transport_init_session(se_sess);
        se_sess->sup_prot_ops = sup_prot_ops;
 
        return se_sess;
@@ -474,8 +460,13 @@ target_setup_session(struct se_portal_group *tpg,
                     int (*callback)(struct se_portal_group *,
                                     struct se_session *, void *))
 {
+       struct target_cmd_counter *cmd_cnt;
        struct se_session *sess;
+       int rc;
 
+       cmd_cnt = target_alloc_cmd_counter();
+       if (!cmd_cnt)
+               return ERR_PTR(-ENOMEM);
        /*
         * If the fabric driver is using percpu-ida based pre allocation
         * of I/O descriptor tags, go ahead and perform that setup now..
@@ -485,29 +476,36 @@ target_setup_session(struct se_portal_group *tpg,
        else
                sess = transport_alloc_session(prot_op);
 
-       if (IS_ERR(sess))
-               return sess;
+       if (IS_ERR(sess)) {
+               rc = PTR_ERR(sess);
+               goto free_cnt;
+       }
+       sess->cmd_cnt = cmd_cnt;
 
        sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
                                        (unsigned char *)initiatorname);
        if (!sess->se_node_acl) {
-               transport_free_session(sess);
-               return ERR_PTR(-EACCES);
+               rc = -EACCES;
+               goto free_sess;
        }
        /*
         * Go ahead and perform any remaining fabric setup that is
         * required before transport_register_session().
         */
        if (callback != NULL) {
-               int rc = callback(tpg, sess, private);
-               if (rc) {
-                       transport_free_session(sess);
-                       return ERR_PTR(rc);
-               }
+               rc = callback(tpg, sess, private);
+               if (rc)
+                       goto free_sess;
        }
 
        transport_register_session(tpg, sess->se_node_acl, sess, private);
        return sess;
+
+free_sess:
+       transport_free_session(sess);
+free_cnt:
+       target_free_cmd_counter(cmd_cnt);
+       return ERR_PTR(rc);
 }
 EXPORT_SYMBOL(target_setup_session);
 
@@ -632,7 +630,8 @@ void transport_free_session(struct se_session *se_sess)
                sbitmap_queue_free(&se_sess->sess_tag_pool);
                kvfree(se_sess->sess_cmd_map);
        }
-       transport_uninit_session(se_sess);
+       if (se_sess->cmd_cnt)
+               target_free_cmd_counter(se_sess->cmd_cnt);
        kmem_cache_free(se_sess_cache, se_sess);
 }
 EXPORT_SYMBOL(transport_free_session);

diff --git a/drivers/target/target_core_xcopy.c b/drivers/target/target_core_xcopy.c
index 49eaee0..49a8350 100644 (file)
--- a/drivers/target/target_core_xcopy.c
+++ b/drivers/target/target_core_xcopy.c
@@ -461,8 +461,6 @@ static const struct target_core_fabric_ops xcopy_pt_tfo = {
 
 int target_xcopy_setup_pt(void)
 {
-       int ret;
-
        xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
        if (!xcopy_wq) {
                pr_err("Unable to allocate xcopy_wq\n");
@@ -479,9 +477,7 @@ int target_xcopy_setup_pt(void)
        INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
        INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
        memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
-       ret = transport_init_session(&xcopy_pt_sess);
-       if (ret < 0)
-               goto destroy_wq;
+       transport_init_session(&xcopy_pt_sess);
 
        xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
        xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
@@ -490,19 +486,12 @@ int target_xcopy_setup_pt(void)
        xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
 
        return 0;
-
-destroy_wq:
-       destroy_workqueue(xcopy_wq);
-       xcopy_wq = NULL;
-       return ret;
 }
 
 void target_xcopy_release_pt(void)
 {
-       if (xcopy_wq) {
+       if (xcopy_wq)
                destroy_workqueue(xcopy_wq);
-               transport_uninit_session(&xcopy_pt_sess);
-       }
 }
 
 /*

diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h
index 38f0662..6552717 100644 (file)
--- a/include/target/target_core_fabric.h
+++ b/include/target/target_core_fabric.h
@@ -133,7 +133,9 @@ struct se_session *target_setup_session(struct se_portal_group *,
                                struct se_session *, void *));
 void target_remove_session(struct se_session *);
 
-int transport_init_session(struct se_session *se_sess);
+struct target_cmd_counter *target_alloc_cmd_counter(void);
+
+void transport_init_session(struct se_session *se_sess);
 struct se_session *transport_alloc_session(enum target_prot_op);
 int transport_alloc_session_tags(struct se_session *, unsigned int,
                unsigned int);