From c0add7fd05ff99c3a516c78eb6b1e6460a3efdae Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Fri, 7 Jun 2013 17:38:58 -0700 Subject: [PATCH] target: Add transport_init_session_tags using per-cpu ida This patch adds lib/idr.c based transport_init_session_tags() logic that allows fabric drivers to setup a per-cpu se_sess->sess_tag_pool and associated se_sess->sess_cmd_map for basic tagged pre-allocation of fabric descriptor sized memory. v5 changes: - Convert to percpu_ida.h include v4 changes: - Add transport_alloc_session_tags() for fabrics that need early transport_init_session() v3 changes: - Update to percpu-ida usage Cc: Kent Overstreet Cc: Asias He Cc: Michael S. Tsirkin Reviewed-by: Asias He Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 48 ++++++++++++++++++++++++++ include/target/target_core_base.h | 5 +++ include/target/target_core_fabric.h | 3 ++ 3 files changed, 56 insertions(+) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 7172d005d063..98ec7110873b 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -232,6 +232,50 @@ struct se_session *transport_init_session(void) } EXPORT_SYMBOL(transport_init_session); +int transport_alloc_session_tags(struct se_session *se_sess, + unsigned int tag_num, unsigned int tag_size) +{ + int rc; + + se_sess->sess_cmd_map = kzalloc(tag_num * tag_size, GFP_KERNEL); + if (!se_sess->sess_cmd_map) { + pr_err("Unable to allocate se_sess->sess_cmd_map\n"); + return -ENOMEM; + } + + rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num); + if (rc < 0) { + pr_err("Unable to init se_sess->sess_tag_pool," + " tag_num: %u\n", tag_num); + kfree(se_sess->sess_cmd_map); + se_sess->sess_cmd_map = NULL; + return -ENOMEM; + } + + return 0; +} +EXPORT_SYMBOL(transport_alloc_session_tags); + +struct se_session *transport_init_session_tags(unsigned int tag_num, + unsigned int tag_size) +{ + struct se_session *se_sess; + int rc; + + se_sess = transport_init_session(); + if (IS_ERR(se_sess)) + return se_sess; + + rc = transport_alloc_session_tags(se_sess, tag_num, tag_size); + if (rc < 0) { + transport_free_session(se_sess); + return ERR_PTR(-ENOMEM); + } + + return se_sess; +} +EXPORT_SYMBOL(transport_init_session_tags); + /* * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called. */ @@ -367,6 +411,10 @@ EXPORT_SYMBOL(transport_deregister_session_configfs); void transport_free_session(struct se_session *se_sess) { + if (se_sess->sess_cmd_map) { + percpu_ida_destroy(&se_sess->sess_tag_pool); + kfree(se_sess->sess_cmd_map); + } kmem_cache_free(se_sess_cache, se_sess); } EXPORT_SYMBOL(transport_free_session); diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index e34fc904f2e1..bd55acd43005 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -415,6 +416,8 @@ struct se_cmd { enum dma_data_direction data_direction; /* For SAM Task Attribute */ int sam_task_attr; + /* Used for se_sess->sess_tag_pool */ + unsigned int map_tag; /* Transport protocol dependent state, see transport_state_table */ enum transport_state_table t_state; unsigned cmd_wait_set:1; @@ -536,6 +539,8 @@ struct se_session { struct list_head sess_wait_list; spinlock_t sess_cmd_lock; struct kref sess_kref; + void *sess_cmd_map; + struct percpu_ida sess_tag_pool; }; struct se_device; diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h index 7a16178424f9..d559c36692af 100644 --- a/include/target/target_core_fabric.h +++ b/include/target/target_core_fabric.h @@ -84,6 +84,9 @@ struct target_core_fabric_ops { }; struct se_session *transport_init_session(void); +int transport_alloc_session_tags(struct se_session *, unsigned int, + unsigned int); +struct se_session *transport_init_session_tags(unsigned int, unsigned int); void __transport_register_session(struct se_portal_group *, struct se_node_acl *, struct se_session *, void *); void transport_register_session(struct se_portal_group *,