From 7221d7e59d1c675828b6de50b757cd8282011a5d Mon Sep 17 00:00:00 2001 From: Yi Zou Date: Wed, 21 Oct 2009 16:27:52 -0700 Subject: [SCSI] fcoe: Use NETIF_F_FCOE_MTU flag to set up max frame size (lport->mfs) 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 Signed-off-by: Robert Love Signed-off-by: James Bottomley --- drivers/scsi/fcoe/fcoe.c | 10 ++++++++-- drivers/scsi/fcoe/fcoe.h | 6 ++++++ 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c index 8702c8d728d..c66b9fa7d67 100644 --- a/drivers/scsi/fcoe/fcoe.c +++ b/drivers/scsi/fcoe/fcoe.c @@ -439,8 +439,12 @@ 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 = netdev->mtu - (sizeof(struct fcoe_hdr) + - sizeof(struct fcoe_crc_eof)); + mfs = netdev->mtu; + if (netdev->features & NETIF_F_FCOE_MTU) { + mfs = FCOE_MTU; + FCOE_NETDEV_DBG(netdev, "Supports FCOE_MTU of %d bytes\n", mfs); + } + mfs -= (sizeof(struct fcoe_hdr) + sizeof(struct fcoe_crc_eof)); if (fc_set_mfs(lp, mfs)) return -EINVAL; @@ -1570,6 +1574,8 @@ static int fcoe_device_notification(struct notifier_block *notifier, case NETDEV_CHANGE: break; case NETDEV_CHANGEMTU: + if (netdev->features & NETIF_F_FCOE_MTU) + break; mfs = netdev->mtu - (sizeof(struct fcoe_hdr) + sizeof(struct fcoe_crc_eof)); if (mfs >= FC_MIN_MAX_FRAME) diff --git a/drivers/scsi/fcoe/fcoe.h b/drivers/scsi/fcoe/fcoe.h index ce7f60fb1bc..c578082aef8 100644 --- a/drivers/scsi/fcoe/fcoe.h +++ b/drivers/scsi/fcoe/fcoe.h @@ -40,6 +40,12 @@ #define FCOE_MIN_XID 0x0000 /* the min xid supported by fcoe_sw */ #define FCOE_MAX_XID 0x0FFF /* the max xid supported by fcoe_sw */ +/* + * 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 + unsigned int fcoe_debug_logging; module_param_named(debug_logging, fcoe_debug_logging, int, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels"); -- cgit v1.2.3-70-g09d2