From: Robert Love Date: Sat, 11 Feb 2012 01:18:41 +0000 (-0800) Subject: [SCSI] fcoe: Do not switch context in vport_delete callback X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ccefd23ed2d683ad3c0282280e6e6d0b163ad041;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git [SCSI] fcoe: Do not switch context in vport_delete callback Currently all port deletion is routed though the FCoE workqueue (fcoe_wq). When fc_remove_host is called on an N_Port (for example, from fcoe_destroy) the vports are queued into a FC Transport workqueue. fc_remove_host flushes that queue and each vport is passed to fcoe's fcoe_vport_destroy, which simply queues the associated fcoe_ports for later deletion. This queue cannot be flushed within the N_Ports destroy path because of circular locking issues. The result is that the NPIV ports are destroyed after the N_Port, which is reverse of how they are created. This quirk causes fcoe to keep references on the fcoe_interface shared by each of these ports (N_Port and NPIV). Changing the ordering such that NPIV ports are destroyed before the N_Port will allow us to remove reference counting on the fcoe_interface instances. This patch simply allows fcoe_vport_destory to destroy NPIV ports without deferring them to a workqueue context. This ensures that when fc_remove_host is called the NPIV ports will be destroyed first before the N_Port and allows reference counting on the fcoe's fcoe_interface to be remove in a later patch. Signed-off-by: Robert Love Tested-by: Ross Brattain Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c index 449d31ea07bd..5126685ab982 100644 --- a/drivers/scsi/fcoe/fcoe.c +++ b/drivers/scsi/fcoe/fcoe.c @@ -2107,20 +2107,14 @@ static void fcoe_destroy_work(struct work_struct *work) { struct fcoe_port *port; struct fcoe_interface *fcoe; - int npiv = 0; port = container_of(work, struct fcoe_port, destroy_work); mutex_lock(&fcoe_config_mutex); - /* set if this is an NPIV port */ - npiv = port->lport->vport ? 1 : 0; - fcoe = port->priv; fcoe_if_destroy(port->lport); - /* Do not tear down the fcoe interface for NPIV port */ - if (!npiv) - fcoe_interface_cleanup(fcoe); + fcoe_interface_cleanup(fcoe); mutex_unlock(&fcoe_config_mutex); } @@ -2691,12 +2685,15 @@ static int fcoe_vport_destroy(struct fc_vport *vport) struct Scsi_Host *shost = vport_to_shost(vport); struct fc_lport *n_port = shost_priv(shost); struct fc_lport *vn_port = vport->dd_data; - struct fcoe_port *port = lport_priv(vn_port); mutex_lock(&n_port->lp_mutex); list_del(&vn_port->list); mutex_unlock(&n_port->lp_mutex); - queue_work(fcoe_wq, &port->destroy_work); + + mutex_lock(&fcoe_config_mutex); + fcoe_if_destroy(vn_port); + mutex_unlock(&fcoe_config_mutex); + return 0; }