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path: root/drivers/scsi/fcoe
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2009-03-06[SCSI] libfc, fcoe: fixed locking issues with lport->lp_mutex around ↵Vasu Dev
lport->link_status The fcoe_xmit could call fc_pause in case the pending skb queue len is larger than FCOE_MAX_QUEUE_DEPTH, the fc_pause was trying to grab lport->lp_muex to change lport->link_status and that had these issues :- 1. The fcoe_xmit was getting called with bh disabled, thus causing "BUG: scheduling while atomic" when grabbing lport->lp_muex with bh disabled. 2. fc_linkup and fc_linkdown function calls lport_enter function with lport->lp_mutex held and these enter function in turn calls fcoe_xmit to send lport related FC frame, e.g. fc_linkup => fc_lport_enter_flogi to send flogi req. In this case grabbing the same lport->lp_mutex again in fc_puase from fcoe_xmit would cause deadlock. The lport->lp_mutex was used for setting FC_PAUSE in fcoe_xmit path but FC_PAUSE bit was not used anywhere beside just setting and clear this bit in lport->link_status, instead used a separate field qfull in fc_lport to eliminate need for lport->lp_mutex to track pending queue full condition and in turn avoid above described two locking issues. Also added check for lp->qfull in fc_fcp_lport_queue_ready to trigger SCSI_MLQUEUE_HOST_BUSY when lp->qfull is set to prevent more scsi-ml cmds while lp->qfull is set. This patch eliminated FC_LINK_UP and FC_PAUSE and instead used dedicated fields in fc_lport for this, this simplified all related conditional code. Also removed fc_pause and fc_unpause functions and instead used newly added lport->qfull directly in fcoe. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-30[SCSI] fcoe: fix incorrect use of struct moduleJames Bottomley
This structure may not be defined if CONFIG_MODULE=n, so never deref it. Change uses of module->name to module_name(module) and corrects some dyslexic printks and docbook comments. Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29[SCSI] fcoe: Fibre Channel over EthernetRobert Love
Encapsulation protocol for running Fibre Channel over Ethernet interfaces. Creates virtual Fibre Channel host adapters using libfc. This layer is the LLD to the scsi-ml. It allocates the Scsi_Host, utilizes libfc for Fibre Channel protocol processing and interacts with netdev to send/receive Ethernet packets. Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>