target: Add target_alloc_session() helper function
Based on HCH's original patch, this adds a full version to
support percpu-ida tag pre-allocation and callback function
pointer into fabric driver code to complete session setup.
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 867bc6d..f5ad9e0 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -281,6 +281,17 @@
struct se_session *se_sess;
int rc;
+ if (tag_num != 0 && !tag_size) {
+ pr_err("init_session_tags called with percpu-ida tag_num:"
+ " %u, but zero tag_size\n", tag_num);
+ return ERR_PTR(-EINVAL);
+ }
+ if (!tag_num && tag_size) {
+ pr_err("init_session_tags called with percpu-ida tag_size:"
+ " %u, but zero tag_num\n", tag_size);
+ return ERR_PTR(-EINVAL);
+ }
+
se_sess = transport_init_session(sup_prot_ops);
if (IS_ERR(se_sess))
return se_sess;
@@ -374,6 +385,51 @@
}
EXPORT_SYMBOL(transport_register_session);
+struct se_session *
+target_alloc_session(struct se_portal_group *tpg,
+ unsigned int tag_num, unsigned int tag_size,
+ enum target_prot_op prot_op,
+ const char *initiatorname, void *private,
+ int (*callback)(struct se_portal_group *,
+ struct se_session *, void *))
+{
+ struct se_session *sess;
+
+ /*
+ * If the fabric driver is using percpu-ida based pre allocation
+ * of I/O descriptor tags, go ahead and perform that setup now..
+ */
+ if (tag_num != 0)
+ sess = transport_init_session_tags(tag_num, tag_size, prot_op);
+ else
+ sess = transport_init_session(prot_op);
+
+ if (IS_ERR(sess))
+ return sess;
+
+ 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);
+ }
+ /*
+ * 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);
+ }
+ }
+
+ transport_register_session(tpg, sess->se_node_acl, sess, private);
+ return sess;
+}
+EXPORT_SYMBOL(target_alloc_session);
+
static void target_release_session(struct kref *kref)
{
struct se_session *se_sess = container_of(kref,