From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: [PATCH 35/36] scsi_dh_alua: update 'access_state' field Date: Tue, 29 Sep 2015 12:47:37 +0200 Message-ID: <1443523658-87622-36-git-send-email-hare@suse.de> References: <1443523658-87622-1-git-send-email-hare@suse.de> Return-path: Received: from mx2.suse.de ([195.135.220.15]:41992 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934696AbbI2KsB (ORCPT ); Tue, 29 Sep 2015 06:48:01 -0400 In-Reply-To: <1443523658-87622-1-git-send-email-hare@suse.de> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: linux-scsi@vger.kernel.org, Christoph Hellwig , Bart van Assche , Ewan Milne , "Martin K. Petersen" , Hannes Reinecke Track attached SCSI devices and update the 'access_state' field whenever an ALUA state change has been detected. Signed-off-by: Hannes Reinecke --- drivers/scsi/device_handler/scsi_dh_alua.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index d9c7b42..12e6ce9 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -72,6 +73,7 @@ static struct workqueue_struct *kaluad_wq; struct alua_port_group { struct kref kref; struct list_head node; + struct list_head dh_list; unsigned char device_id_str[256]; int device_id_len; int group_id; @@ -89,6 +91,7 @@ struct alua_port_group { }; struct alua_dh_data { + struct list_head node; struct alua_port_group *pg; int rel_port; spinlock_t pg_lock; @@ -243,6 +246,7 @@ struct alua_port_group *alua_get_pg(struct scsi_device *sdev, INIT_DELAYED_WORK(&pg->rtpg_work, alua_rtpg_work); INIT_LIST_HEAD(&pg->rtpg_list); INIT_LIST_HEAD(&pg->node); + INIT_LIST_HEAD(&pg->dh_list); spin_lock_init(&pg->lock); /* Re-check list again to catch concurrent updates */ @@ -371,13 +375,26 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h, old_pg = pg; /* port_group has changed. Update to new port group */ if (h->pg != pg) { + unsigned long flags; + old_pg = h->pg; rcu_assign_pointer(h->pg, pg); + spin_lock_irqsave(&old_pg->lock, flags); + list_del_rcu(&h->node); + spin_unlock_irqrestore(&old_pg->lock, flags); + spin_lock_irqsave(&pg->lock, flags); + list_add_rcu(&h->node, &pg->dh_list); + spin_unlock_irqrestore(&pg->lock, flags); h->pg->expiry = 0; pg_found = true; } } else { + unsigned long flags; + rcu_assign_pointer(h->pg, pg); + spin_lock_irqsave(&pg->lock, flags); + list_add_rcu(&h->node, &pg->dh_list); + spin_unlock_irqrestore(&pg->lock, flags); pg_found = true; } alua_rtpg_queue(h->pg, sdev, NULL, true); @@ -629,6 +646,8 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg) spin_lock_irqsave(&port_group_lock, flags); list_for_each_entry(tmp_pg, &port_group_list, node) { + struct alua_dh_data *h; + if (tmp_pg->group_id != group_id) continue; if (tmp_pg->device_id_len != pg->device_id_len) @@ -638,6 +657,12 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg) continue; tmp_pg->state = desc[0] & 0x0f; tmp_pg->pref = desc[0] >> 7; + rcu_read_lock(); + list_for_each_entry_rcu(h, &tmp_pg->dh_list, node) { + if (h->sdev) + h->sdev->access_state = desc[0]; + } + rcu_read_unlock(); if (tmp_pg == pg) valid_states = desc[1]; } @@ -1054,6 +1079,7 @@ static int alua_bus_attach(struct scsi_device *sdev) h->rel_port = -1; h->init_error = SCSI_DH_OK; h->sdev = sdev; + INIT_LIST_HEAD(&h->node); mutex_init(&h->init_mutex); err = alua_initialize(sdev, h); @@ -1084,6 +1110,9 @@ static void alua_bus_detach(struct scsi_device *sdev) h->sdev = NULL; spin_unlock(&h->pg_lock); if (pg) { + spin_lock(&pg->lock); + list_del_rcu(&h->node); + spin_unlock(&pg->lock); synchronize_rcu(); if (pg->rtpg_sdev) flush_delayed_work(&pg->rtpg_work); -- 1.8.5.6