diff options
Diffstat (limited to 'drivers/target/target_core_transport.c')
| -rw-r--r-- | drivers/target/target_core_transport.c | 35 |
1 files changed, 5 insertions, 30 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 4d1651e46ea9..0c8eca6ae30f 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2911,38 +2911,13 @@ void target_wait_for_sess_cmds(struct se_session *se_sess) } EXPORT_SYMBOL(target_wait_for_sess_cmds); -static void target_lun_confirm(struct percpu_ref *ref) -{ - struct se_lun *lun = container_of(ref, struct se_lun, lun_ref); - - complete(&lun->lun_ref_comp); -} - +/* + * Prevent that new percpu_ref_tryget_live() calls succeed and wait until + * all references to the LUN have been released. Called during LUN shutdown. + */ void transport_clear_lun_ref(struct se_lun *lun) { - /* - * Mark the percpu-ref as DEAD, switch to atomic_t mode, drop - * the initial reference and schedule confirm kill to be - * executed after one full RCU grace period has completed. - */ - percpu_ref_kill_and_confirm(&lun->lun_ref, target_lun_confirm); - /* - * The first completion waits for percpu_ref_switch_to_atomic_rcu() - * to call target_lun_confirm after lun->lun_ref has been marked - * as __PERCPU_REF_DEAD on all CPUs, and switches to atomic_t - * mode so that percpu_ref_tryget_live() lookup of lun->lun_ref - * fails for all new incoming I/O. - */ - wait_for_completion(&lun->lun_ref_comp); - /* - * The second completion waits for percpu_ref_put_many() to - * invoke ->release() after lun->lun_ref has switched to - * atomic_t mode, and lun->lun_ref.count has reached zero. - * - * At this point all target-core lun->lun_ref references have - * been dropped via transport_lun_remove_cmd(), and it's safe - * to proceed with the remaining LUN shutdown. - */ + percpu_ref_kill(&lun->lun_ref); wait_for_completion(&lun->lun_shutdown_comp); } |