From: Yi Zou <[email protected]> Add a define of FCOE_MTU as 2158 bytes and use FCOE_MTU when the LLD is found to support NETIF_F_FCOE_MTU. The lport->mfs is then calculated out of the 2158 FCOE_MTU. Otherwise, we stick with the netdev->mtu, i.e., LAN MTU. Also, change the notification on NETDEV_CHANGEMTU event to bypass changing mfs when LAN MTU is changed if NETIF_F_FCOE_MTU is supported.
Signed-off-by: Yi Zou <[email protected]> Signed-off-by: Jeff Kirsher <[email protected]> --- drivers/scsi/fcoe/fcoe.c | 11 +++++++++-- drivers/scsi/fcoe/fcoe.h | 4 ++++ 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c index 0a5609b..e0a885c 100644 --- a/drivers/scsi/fcoe/fcoe.c +++ b/drivers/scsi/fcoe/fcoe.c @@ -291,8 +291,13 @@ static int fcoe_netdev_config(struct fc_lport *lp, struct net_device *netdev) * user-configured limit. If the MFS is too low, fcoe_link_ok() * will return 0, so do this first. */ - mfs = fc->real_dev->mtu - (sizeof(struct fcoe_hdr) + - sizeof(struct fcoe_crc_eof)); + mfs = fc->real_dev->mtu; + if (fc->phys_dev->features & NETIF_F_FCOE_MTU) { + mfs = FCOE_MTU; + printk(KERN_DEBUG "fcoe:%s supports FCOE_MTU of %d bytes\n", + netdev->name, mfs); + } + mfs -= (sizeof(struct fcoe_hdr) + sizeof(struct fcoe_crc_eof)); if (fc_set_mfs(lp, mfs)) return -EINVAL; @@ -1420,6 +1425,8 @@ static int fcoe_device_notification(struct notifier_block *notifier, case NETDEV_CHANGE: break; case NETDEV_CHANGEMTU: + if (fc->phys_dev->features & NETIF_F_FCOE_MTU) + break; mfs = fc->real_dev->mtu - (sizeof(struct fcoe_hdr) + sizeof(struct fcoe_crc_eof)); diff --git a/drivers/scsi/fcoe/fcoe.h b/drivers/scsi/fcoe/fcoe.h index 0d724fa..be9735d 100644 --- a/drivers/scsi/fcoe/fcoe.h +++ b/drivers/scsi/fcoe/fcoe.h @@ -64,6 +64,10 @@ do { \ printk(KERN_INFO "fcoe: %s" fmt, \ netdev->name, ##args);) +/* Max MTU for FCoE: 14 (FCoE header) + 24 (FC header) + 2112 (max FC payload) + * + 4 (FC CRC) + 4 (FCoE trailer) = 2158 bytes */ +#define FCOE_MTU 2158 + /* * this percpu struct for fcoe */ _______________________________________________ devel mailing list [email protected] http://www.open-fcoe.org/mailman/listinfo/devel
