From d29425b065cdab5c5e65a48108adde5ea72d4656 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 1 Dec 2016 11:30:50 -0800 Subject: [PATCH] scsi: scsi_dh_alua: Fix RCU annotations This patch avoids that sparse complains about RCU pointer dereferences. Signed-off-by: Bart Van Assche Cc: Hannes Reinecke Cc: tang.junhui Reviewed-by: Christoph Hellwig Signed-off-by: Martin K. Petersen --- drivers/scsi/device_handler/scsi_dh_alua.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 241829e59668..32e48cc4cf71 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -95,7 +95,7 @@ struct alua_port_group { struct alua_dh_data { struct list_head node; - struct alua_port_group *pg; + struct alua_port_group __rcu *pg; int group_id; spinlock_t pg_lock; struct scsi_device *sdev; @@ -369,7 +369,7 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h, /* Check for existing port group references */ spin_lock(&h->pg_lock); - old_pg = h->pg; + old_pg = rcu_dereference_protected(h->pg, lockdep_is_held(&h->pg_lock)); if (old_pg != pg) { /* port group has changed. Update to new port group */ if (h->pg) { @@ -388,7 +388,9 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h, list_add_rcu(&h->node, &pg->dh_list); spin_unlock_irqrestore(&pg->lock, flags); - alua_rtpg_queue(h->pg, sdev, NULL, true); + alua_rtpg_queue(rcu_dereference_protected(h->pg, + lockdep_is_held(&h->pg_lock)), + sdev, NULL, true); spin_unlock(&h->pg_lock); if (old_pg) @@ -937,7 +939,7 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) static int alua_set_params(struct scsi_device *sdev, const char *params) { struct alua_dh_data *h = sdev->handler_data; - struct alua_port_group __rcu *pg = NULL; + struct alua_port_group *pg = NULL; unsigned int optimize = 0, argc; const char *p = params; int result = SCSI_DH_OK; @@ -984,7 +986,7 @@ static int alua_activate(struct scsi_device *sdev, struct alua_dh_data *h = sdev->handler_data; int err = SCSI_DH_OK; struct alua_queue_data *qdata; - struct alua_port_group __rcu *pg; + struct alua_port_group *pg; qdata = kzalloc(sizeof(*qdata), GFP_KERNEL); if (!qdata) { @@ -1048,7 +1050,7 @@ static void alua_check(struct scsi_device *sdev, bool force) static int alua_prep_fn(struct scsi_device *sdev, struct request *req) { struct alua_dh_data *h = sdev->handler_data; - struct alua_port_group __rcu *pg; + struct alua_port_group *pg; unsigned char state = SCSI_ACCESS_STATE_OPTIMAL; int ret = BLKPREP_OK; @@ -1118,7 +1120,7 @@ static void alua_bus_detach(struct scsi_device *sdev) struct alua_port_group *pg; spin_lock(&h->pg_lock); - pg = h->pg; + pg = rcu_dereference_protected(h->pg, lockdep_is_held(&h->pg_lock)); rcu_assign_pointer(h->pg, NULL); h->sdev = NULL; spin_unlock(&h->pg_lock); -- 2.20.1