Commit Graph

14 Commits

Author SHA1 Message Date
Robert Love
34f42a070f [SCSI] libfc, fcoe: Fix kerneldoc comments
1) Added '()' for function names in kerneldoc comments

2) Changed comment bookends from '**/' to '*/'. The comment on the the
   mailing list was that '**/' "is consistently unconventional.  Not
   wrong, just odd." The Documentation/kernel-doc-nano-HOWTO.txt
   states that kerneldoc comment blocks should end with '**/' but most
   (if not all) instance I found under drivers/scsi/ were only using
   the '*/' so I converted to that style.

3) Removed incorrect linebreaks in kerneldoc comments where found

4) Removed a few unnecessary blank comment lines in kerneldoc comment
   blocks

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:04:40 -05:00
Robert Love
efaf5c085d [SCSI] libfc: check for err when recv and state is incorrect
If we've just created an interface and the an rport is
logging in we may have a request on the wire (say PRLI).
If we destroy the interface, we'll go through each rport
on the disc->rports list and set each rport's state to NONE.
Then the lport will reset the EM. The EM reset will send a
CLOSED event to the prli_resp() handler which will notice
that the state != PRLI. In this case it frees the frame
pointer, decrements the refcount and unlocks the rport.

The problem is that there isn't a frame in this case. It's
just a pointer with an embedded error code. The free causes
an Oops.

This patch moves the error checking to be before the state
checking.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:44:36 -06:00
Robert Love
d3b33327ca [SCSI] libfc: rename rp to rdata in fc_disc_new_target()
Just rename the variable as per our naming convention.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:41:37 -06:00
Robert Love
23f11f9076 [SCSI] libfc: correct RPORT_TO_PRIV usage
We only need to use this macro when assigning a value to
rport->dd_data. All other accesses should just use dd_data.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:41:16 -06:00
Robert Love
5101ff99f5 [SCSI] libfc: Don't violate transport template for rogue port creation
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:41:01 -06:00
Steve Ma
f7db2c150c [SCSI] libfc: exch mgr is freed while lport still retrying sequences
When a sequence cannot be delivered to the target, the local
port will schedule retries, While this process is in progress,
if we destroy the FCoE interface, the fcoe_sw_destroy routine is
entered, and the fc_exch_mgr_free(lp->emp) is called.  Thus
if fc_exch_alloc() is called when retrying the sequence,
the mempool_alloc() will fail to allocate the exchange because
the mempool of the exchange manager has already been released.
This patch is to cancel any pending retry work of the local
port before we start to destroy the interface.

Also, when resetting the local port, we should also stop the
scheduled pending retries.

Signed-off-by: Steve Ma <steve.ma@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:40:45 -06:00
Vasu Dev
26d9cab558 [SCSI] libfc: fixed a read IO data integrity issue when a IO data frame lost
The fc_fcp_complete_locked detected data underrun in this case and set
the FC_DATA_UNDRUN but that was ignored by fc_io_compl for all cases
including read underrun.

Added code to not to ignore FC_DATA_UNDRUN for read IO and instead
suggested scsi-ml to retry cmd to  recover from lost data frame.

Not sure if it is okay to ignore FC_DATA_UNDRUN for other case, so let
code as is for other cases but removed or-ing with zero valued fsp->cdb_status
for those cases.

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>
2009-03-06 15:40:06 -06:00
Chris Leech
6755db1cd4 [SCSI] libfc: rport retry on LS_RJT from certain ELS
This allows any rport ELS to retry on LS_RJT.

The rport error handling would only retry on resource allocation failures
and exchange timeouts.  I have a target that will occasionally reject PLOGI
when we do a quick LOGO/PLOGI.  When a critical ELS was rejected, libfc would
fail silently leaving the rport in a dead state.

The retry count and delay are managed by fc_rport_error_retry.  If the retry
count is exceeded fc_rport_error will be called.  When retrying is not the
correct course of action, fc_rport_error can be called directly.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:39:34 -06:00
Vasu Dev
bc0e17f691 [SCSI] libfc, fcoe: fixed locking issues with lport->lp_mutex around 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>
2009-03-06 15:37:49 -06:00
Vasu Dev
a7e84f2b83 [SCSI] libfc: fixed a soft lockup issue in fc_exch_recv_abts
The fc_seq_start_next grabs ep->ex_lock but this lock was already held here,
so instead called fc_seq_start_next_locked to avoid soft lockup.

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>
2009-03-06 15:37:23 -06:00
Vasu Dev
78342da368 [SCSI] libfc: handle RRQ exch timeout
Cleanup exchange held due to RRQ when RRQ exch times out, in this case the
ABTS is already done causing RRQ req therefore proceeding with cleanup in
fc_exch_rrq_resp should be okay to restore exch resource.

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>
2009-03-06 15:36:56 -06:00
Abhijeet Joglekar
571f824c3c [SCSI] libfc: when rport goes away (re-plogi), clean up exchanges to/from rport
When a rport goes away, libFC does a plogi which will reset exchanges
    at the rport. Clean exchanges at our end, both in transport and libFC.
    If transport hooks into exch_mgr_reset, it will call back into
    fc_exch_mgr_reset() to clean up libFC exchanges.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:36:28 -06:00
Abhijeet Joglekar
1f6ff364ce [SCSI] libfc: Pass lport in exch_mgr_reset
fc_exch_mgr structure is private to fc_exch.c. To export exch_mgr_reset to
transport, transport needs access to the exch manager. Change
exch_mgr_reset to use lport param which is the shared structure between
libFC and transport.

Alternatively, fc_exch_mgr definition can be moved to libfc.h so that lport
can be accessed from mp*.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:35:47 -06:00
Robert Love
42e9a92fe6 [SCSI] libfc: A modular Fibre Channel library
libFC is composed of 4 blocks supported by an exchange manager
and a framing library. The upper 4 layers are fc_lport, fc_disc,
fc_rport and fc_fcp. A LLD that uses libfc could choose to
either use libfc's block, or using the transport template
defined in libfc.h, override one or more blocks with its own
implementation.

The EM (Exchange Manager) manages exhcanges/sequences for all
commands- ELS, CT and FCP.

The framing library frames ELS and CT commands.

The fc_lport block manages the library's representation of the
host's FC enabled ports.

The fc_disc block manages discovery of targets as well as
handling changes that occur in the FC fabric (via. RSCN events).

The fc_rport block manages the library's representation of other
entities in the FC fabric. Currently the library uses this block
for targets, its peer when in point-to-point mode and the
directory server, but can be extended for other entities if
needed.

The fc_fcp block interacts with the scsi-ml and handles all
I/O.

Signed-off-by: Robert Love <robert.w.love@intel.com>
[jejb: added include of delay.h to fix ppc64 compile prob spotted by sfr]
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:33 -06:00