From 9d34876f820d55c94bd0b2a2ed3d2e2976cbd997 Mon Sep 17 00:00:00 2001 From: Robert Love Date: Thu, 5 Sep 2013 07:47:27 +0000 Subject: libfcoe: Make fcoe_sysfs optional / fix fnic NULL exception fnic doesn't use any of the create/destroy/enable/disable interfaces either from the (legacy) module paramaters or the (new) fcoe_sysfs interfaces. When fcoe_sysfs was introduced fnic wasn't changed since it wasn't using the interfaces. libfcoe incorrectly assumed that that all of its users were using fcoe_sysfs and when adding and deleting FCFs would assume the existance of a fcoe_ctlr_device. fnic was not allocating this structure because it doesn't care about the standard user interfaces (fnic starts on link only). If/When libfcoe tried to use the fcoe_ctlr_device's lock for the first time a NULL pointer exception would be triggered. Since fnic doesn't care about sysfs or user interfaces, the solution is to drop libfcoe's assumption that all drivers are using fcoe_sysfs. This patch accomplishes this by changing some of the structure relationships. We need a way to determine when a LLD is using fcoe_sysfs or not and we can do that by checking for the existance of the fcoe_ctlr_device. Prior to this patch, it was assumed that the fcoe_ctlr structure was allocated with the fcoe_ctlr_device and immediately followed it in memory. To reach the fcoe_ctlr_device we would simply go back in memory from the fcoe_ctlr to get the fcoe_ctlr_device. Since fnic doesn't allocate the fcoe_ctlr_device, we cannot keep that assumption. This patch adds a pointer from the fcoe_ctlr to the fcoe_ctlr_device. For bnx2fc and fcoe we will continue to allocate the two structures together, but then we'll set the ctlr->cdev pointer to point at the fcoe_ctlr_device. fnic will not change and will continue to allocate the fcoe_ctlr itself, and ctlr->cdev will remain NULL. When libfcoe adds fcoe_fcf's to the fcoe_ctlr it will check if ctlr->cdev is set and only if so will it continue to interact with fcoe_sysfs. Signed-off-by: Robert Love Acked-by: Neil Horman Tested-by: Hiral Patel --- drivers/scsi/bnx2fc/bnx2fc_fcoe.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/scsi/bnx2fc/bnx2fc_fcoe.c') diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c index 69ac55495c1d..27f2cc4b97a5 100644 --- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c +++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c @@ -1381,6 +1381,7 @@ struct bnx2fc_interface *bnx2fc_interface_create(struct bnx2fc_hba *hba, return NULL; } ctlr = fcoe_ctlr_device_priv(ctlr_dev); + ctlr->cdev = ctlr_dev; interface = fcoe_ctlr_priv(ctlr); dev_hold(netdev); kref_init(&interface->kref); -- cgit v1.2.1