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Author SHA1 Message Date
Joe Eykholt 1d490ce33e [SCSI] libfc: don't swap OX_ID and RX_ID when sending BA_RJT
I saw an lport debug message from the exchange manager saying:
"lport  70500: Received response for out of range oxid:ffff"

A trace showed this was a BA_RJT sent due to an incoming ABTS
which arrived on an unknown exchange.  So, the sender of the
BA_RJT was in error, but in this case, both the initiator and
responder were the same machine.

The OX_ID and RX_ID should not have been reversed in this case.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:03 -05:00
Joe Eykholt 2ab7e1ecb8 [SCSI] libfc: send GPN_ID in reaction to single-port RSCNs.
When an RSCN indicates changes to individual remote ports,
don't blindly log them out and then back in.  Instead, determine
whether they're still in the directory, by doing GPN_ID.

If that is successful, call login, which will send ADISC and reverify,
otherwise, call logoff.  Perhaps we should just delete the rport,
not send LOGO, but it seems safer.

Also, fix a possible issue where if a mix of records in the RSCN
cause us to queue disc_ports for disc_single and then we decide
to do full rediscovery, we leak memory for those disc_ports queued.

So, go through the list of disc_ports even if doing full discovery.
Free the disc_ports in any case.  If any of the disc_single() calls
return error, do a full discovery.

The ability to fill in GPN_ID requests was added to fc_ct_fill().
For this, it needs the FC_ID to be passed in as an arg.
The did parameter for fc_elsct_send() is used for that, since the
actual D_DID will always be 0xfffffc for all CT requests so far.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:03 -05:00
Joe Eykholt 8abbe3a423 [SCSI] libfc: fix handling of incoming Discover Address (ADISC) requests
The local port facility has been replying to ADISC requests without
looking to see if the remote port is logged in.  This is incorrect.
An ADISC request requires PLOGI first.  It should be rejected if
the sending remote port is not logged in.

This is like other incoming requests that require login, all of
which should be handled in the remote port module.

Move the ADISC request handling from fc_lport.c to fc_rport.c.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:02 -05:00
Joe Eykholt 370c3bd05c [SCSI] libfc: use ADISC to verify rport login state
When rport_login is called on an rport that is already thought
to be logged in, use ADISC.  If that fails, redo PLOGI.
This is less disruptive after fabric changes that don't affect
the state of the target.

Implement the sending of ADISC via fc_els_fill.

Add ADISC state to the rport state machine.  This is entered from READY
and returns to READY after successful completion.  If it fails, the rport
is either logged off and deleted or re-does PLOGI.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:02 -05:00
Joe Eykholt 68a1750b46 [SCSI] libfc: LOGO response code had extraeous enter_rtv
fc_rport_logo_resp() had a call to fc_rport_enter_rtv() if the
LOGO was accepted.  This must've been a copy/paste mistake, but
it didn't matter since we don't stay in the LOGO state long enough
to hit this code.

Change fc_rport_logo_resp() to just enter the delete state
no matter what.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:01 -05:00
Joe Eykholt feab4ae730 [SCSI] libfc: re-login to remote ports that send us LOGO
After a quick link flap, a target was seen to send us a LOGO.
Apparently, it saw an RSCN reporting that we had dropped out of the
fabric after we had logged back into it.

This is likely in larger fabrics (more than 2 FC switches) after
a quick link flap at the initiator.  Each link transition causes
an port-specific RSCN to the target.  After the link comes back up,
the initiator successfully discovers and does a PLOGI to the target
before the target sees the first RSCN reporting the initiator is gone,
and it sends a LOGO.  The target may see a subsequent RSCN saying the
port is back, but probably wouldn't send a PLOGI and leaves it
up to the initiator to re-login.

An RSCN can be delayed by the switches due to software layers but a
PLOGI is forwarded in hardware causing the PLOGI to beat the RSCN.

If a remote port is in the discovered set and sends a LOGO, re-login to it.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:01 -05:00
Joe Eykholt 83fe6a9346 [SCSI] libfc: fix rport error handling for login-required and invalid ops
When receiving an ELS request, if the request isn't recognized,
the unsupported operation error should be given even if the port
is not found or not logged in.

Also, the LOGO request shouldn't give the login-required explanation.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:00 -05:00
Joe Eykholt 3ac6f98f41 [SCSI] libfc: correctly handle incoming PLOGI request.
libfc receives PLOGIs from switches which are trying to discover what
kind of devices are present, and from other initiators to find out
if we're a target.

As an initiator, some argue we don't need to handle incoming PLOGI
requests, and we currently reject them from unknown remote ports,
but accept them is we're in the middle of a PLOGI to the remote port.

For eventual target implementations, we want to handle them always.

For incoming PLOGI, don't fail if the rport_priv doesn't exist.
Just create it and go become READY without going through PRLI.  If
PRLI occurs, then our roles will be set and we'll become READY again.

Also, allow incoming PRLI in RTV state.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:00 -05:00
Joe Eykholt f657d299cf [SCSI] libfc: improve debug messages for ELS response handlers
Improve lport and rport debug messages to indicate whether
the response is LS_ACC, LS_RJT, closed, or timeout.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:59 -05:00
Joe Eykholt 25b37b981e [SCSI] libfc: fix: rport_recv_req needs disc_mutex when calling rport_lookup
The rport_lookup function must be called while holding the disc_mutex.
Otherwise, the rdata could be deleted just after that by another thread.

All callers now check the state after grabbing the rdata rp_mutex.
Even though rport_lookup skips ports in DELETE state, it does that
without holding the rdata rp_mutex, so that the state may change.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:59 -05:00
Joe Eykholt 131203a1ef [SCSI] libfc: move remote port lookup for ELS requests into fc_rport.c.
This moves the remote port lookup for incoming ELS requests into
fc_rport.c, in preparation for handing PLOGI and LOGO from
unknown rports.

This changes the arg to rport_recv_req from an rdata to an lport.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:58 -05:00
Robert Love 6bd054cbf3 [SCSI] libfc: Always reset remote port roles when receiving PRLI
Don't trust previous roles, reset them when we receive a PRLI.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:58 -05:00
Robert Love 9737e6a7b5 [SCSI] libfc: Initialize fc_rport_identifiers inside fc_rport_create
Currently these values are initialized by the callers. This was exposed
by a later patch that adds PLOGI request support. The patch failed to
initialize the new remote port's roles and it caused problems. This patch
has the rport_create routine initialize the identifiers and then the
callers can override them with real values.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:57 -05:00
Joe Eykholt 935d0fce44 [SCSI] libfc: don't do discovery before callback is set
It's possible to "restart" discovery before it was started if
an RSCN is received early enough.  We were jumping to 0
due to the disc_callback function pointer not getting set.

Don't restart discovery if disc_callback is NULL.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:56 -05:00
Joe Eykholt 29d898e909 [SCSI] libfc: clean up point-to-point discovery code.
The discovery code had a special-case for the point-to-point mode,
which used a bunch of code that wasn't really needed.

Now that rport_create adds the rport to the discovery list,
completely skip discovery for the point-to-point case.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:53 -05:00
Joe Eykholt 81a67b9717 [SCSI] libfc: discovery gpn_ft parse bug
In fc_disc_gpn_ft_parse(), after fc_disc_done() is called, the
disc state is changed by setting buf_len = 0.  This is wrong
since the discovery may have restarted.   Instead, return
after calling fc_disc_done.

Also, return an error on memory allocation failure.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:52 -05:00
Joe Eykholt 3667d7e7f7 [SCSI] libfc: discovery retry should clear pending first.
Currently fc_disc_timeout() restarts discovery only if it is not pending.
When the timer is scheduled, the discovery is left pending, so the
timeout never restarts it.

Fix by not checking for pending in the timeout handler.

If discovery is stopped and restarted in the meantime, the timeout will
be canceled.

Also, when a new discovery is started, the retry count wasn't cleared.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:51 -05:00
Joe Eykholt c762608bf7 [SCSI] libfc: fix: empty zone causes endless discovery retries.
On some switches, an empty zone causes GPN_FT to be rejected
with reason 9 (unable) explanation 7 (FC-4 types not registered),
which causes discovery to be retried endlessly.  Treat this as
just an empty response and consider discovery complete.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:50 -05:00
Joe Eykholt 883a337cf8 [SCSI] libfc: handle discovery failure more correctly.
Abhijeet Joglekar wrote: "In gpn_ft_resp, if the payload is short,
or unexpected response or out of sequence frame, then we just
return and do nothing. We should either enter fc_disc_done()
with DISC_EV_FAIL which will then restart any queued discovery
requests or call lport module which will reset local port,
or we should call fc_disc_error() so that the gpn_ft is retried.

The situation as is causes discovery to remain pending and never
get restarted, in these rare cases.  We saw this due to a coding
bug in fc_disc before.  The only ways it could happen would be
bugs, packet corruption or an FC fabric problem.

Change it to fail discovery.  The local port will restart
discovery, although it probably should just give up until
the next link flap.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:50 -05:00
Joe Eykholt a1c1e4e76c [SCSI] libfc: rearrange code in fc_disc_gpn_ft_resp()
Code cleanup for fc_disc_gpn_ft_resp().

Some of the fc_disc.c code was poorly formatted. For example, some lines
in fc_disc.c were unnecessarily truncated and the buf variable could
be eliminated.

Also moved the increment of seq_count into fc_disc_gpn_ft_parse(), to
avoid doing it separately before each call.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:49 -05:00
Joe Eykholt c356afd486 [SCSI] libfc: discovery restart sequence error fix
When an RSCN is received during fabric discovery, it restarts.
After the restart, disc->seq_count was incremented, so when
the first frame was received, it was considered "out of sequence".
That left the state disc->active, preventing further discoveries.

Change to advance the sequence count before parsing, so that it
won't be changed after a potential restart.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:49 -05:00
Joe Eykholt 0f6c614987 [SCSI] libfc: do not log off rports before or after discovery
When receiving an RSCN, do not log off all rports.  This is
extremely disruptive.  If, after the GPN_FT response, some
rports haven't been listed, delete them.

Add field disc_id to structs fc_rport_priv and fc_disc.
disc_id is an arbitrary serial number used to identify the
rports found by the latest discovery.  This eliminates the need
to go through the rport list when restarting discovery.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:48 -05:00
Joe Eykholt 8025b5db7e [SCSI] libfc: move rport_lookup into fc_rport.c
Move the libfc remote port lookup function into fc_rport.c.
This seems like the best place for it.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:47 -05:00
Joe Eykholt 8345592b83 [SCSI] libfc: change to make remote port callback optional
Since the rport list maintenance is now done in the rport module,
the callback (and ops) are usually not necessary.

Allow rdata->ops to be left NULL if nothing needs
to be done in an event callback.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:47 -05:00
Joe Eykholt 19f97e3c0a [SCSI] libfc: have rport_create do a lookup for pre-existing rports first
For future discovery patches, change rport_create to return a previously
created rport_priv that has the FC_ID as long as it isn't in deleted state.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:46 -05:00
Joe Eykholt 48f00902ba [SCSI] libfc: make rport module maintain the rport list
The list of remote ports (struct fc_rport_priv) has been
maintained by the discovery module.  In preparation for having
lport->tt.rport_create() do a lookup first, maintain the
rports list in the rport module.  It will still be protected
by the disc_mutex.

The DNS rport is an exception for until after further patches.
For now, do not add it to the list.

The point-to-point rport will be in the discovery list.
So at shutdown, it doesn't need to be separately logged out.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:46 -05:00
Joe Eykholt b5cbf08373 [SCSI] libfc: simplify fc_lport_rport_callback
The lport rport callback can only be called for the dNS rport,
since its the only rport who's ops point to that function.

Remove unnecessary checking and debug messages.
Put the locking outside the switch statement as a simplification.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:46 -05:00
Joe Eykholt cdbe6dfece [SCSI] libfc: rport debug messages were printing pointer values
Don't print large negative decimal numbers for frame pointers in
the debug messages from fc_rport_error().  Just print 0 if its a
frame pointer, and print the error numbers as positive.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:45 -05:00
Joe Eykholt b84c796265 [SCSI] libfc: remove unused disc->delay element
Delete unused disc->delay element.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:45 -05:00
Joe Eykholt 786681b96f [SCSI] libfc: eliminate disc->event
There was no need to have the discovery status stored in struct fc_disc.

Change fc_disc_done() to take the discovery status as an argument
and just pass it on to the discovery callback.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:44 -05:00
Joe Eykholt 00fea930d4 [SCSI] libfc: fix rport event race between READY and LOGO
When a remote port becomes ready and a LOGO is received before
the READY event is in rport_work waiting on the mutex, the
event is changed to LOGO and the work queued, so both the
calls to rport_work see the LOGO event, and both try to do
the list_del(), causing a crash.

Don't change the event if it is already set.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:44 -05:00
Joe Eykholt 9e9d0452fe [SCSI] libfc: don't create dummy (rogue) remote ports
Don't create a "dummy" remote port to go with fc_rport_priv.

Make the rport truly optional by allocating fc_rport_priv separately
and not requiring a dummy rport to be there if we haven't yet done
fc_remote_port_add().

The fc_rport_libfc_priv remains as a structure attached to the
rport for I/O purposes.

Be sure to hold references on rdata when the lock is dropped in
fc_rport_work().

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:43 -05:00
Joe Eykholt 4c0f62b567 [SCSI] libfc: rename rport event CREATED to READY
Remote ports will become READY more than once after
ADISC is implemented in a later patch.

The event callback that has been called "CREATED" will mean "READY".
Rename it now in preparation for those changes.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:43 -05:00
Joe Eykholt 629f44279d [SCSI] libfc: rearrange code in fc_rport_work
This is a cleanup without semantic changes to use a switch
statement instead of a series of if-statements in fc_rport_work(),
and to move some declarations up to the top.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:42 -05:00
Joe Eykholt f211fa514a [SCSI] libfc: make rport structure optional
Allow a struct fc_rport_priv to have no fc_rport associated with it.
This sets up to remove the need for "rogue" rports.

Add a few fields to fc_rport_priv that are needed before the fc_rport
is created.  These are the ids, maxframe_size, classes, and rport pointer.

Remove the macro PRIV_TO_RPORT().  Just use rdata->rport where appropriate.

To take the place of the get_device()/put_device ops that were used to
hold both the rport and rdata, add a reference count to rdata structures
using kref.  When kref_get decrements the refcount to zero, a new template
function releasing the rdata should be called.  This will take care of
freeing the rdata and releasing the hold on the rport (for now).  After
subsequent patches make the rport truly optional, this release function
will simply free the rdata.

Remove the simple inline function fc_rport_set_name(), which becomes
semanticly ambiguous otherwise.  The caller will set the port_name and
node_name in the rdata->Ids, which will later be copied to the rport
when it its created.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:42 -05:00
Joe Eykholt a46f327aa5 [SCSI] libfc: change elsct to use FC_ID instead of rdata
tt.elsct_send is used by both FCP and by the rport state machine.
After further patches, these two modules will use different
structures for the remote port.

So, change elsct_send to use the FC_ID instead of the fc_rport_priv
as its argument.  It currently only uses the FC_ID anyway.

For CT requests the destination FC_ID is still implicitly 0xfffffc.
After further patches the did arg on CT requests will be used to
specify the FC_ID being inquired about for GPN_ID or other queries.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:41 -05:00
Joe Eykholt 9fb9d32831 [SCSI] libfc: make fc_rport_priv the primary rport interface.
The rport and discovery modules deal with remote ports
before fc_remote_port_add() can be done, because the
full set of rport identifiers is not known at early stages.

In preparation for splitting the fc_rport/fc_rport_priv allocation,
make fc_rport_priv the primary interface for the remote port and
discovery engines.

The FCP / SCSI layers still deal with fc_rport and
fc_rport_libfc_priv, however.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:41 -05:00
Joe Eykholt 795d86f55e [SCSI] libfc: change interface for rport_create
The interface for lport->tt.rport_create() takes a fc_disc_port arg,
which is unnatural for most calls.   The only reason for this was
to avoid passing in the local port as an argument, but otherwise
added to complexity.

Simplify by just using lport and fc_rport_identifiers.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:40 -05:00
Joe Eykholt ab28f1fd3b [SCSI] libfc: prepare to split off struct fc_rport_priv from fc_rport_libfc_priv
While the I/O and LLD interfaces use fc_rport_libfc_priv, the
disc and rport interfaces will use fc_rport_priv, which will
be separately allocated.

Change the disc and rport usage of fc_rport_libfc_priv to fc_rport_priv.

Use #define temporarily to make both names equivalent until a
subsequent patch splits them.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:39 -05:00
Vasu Dev b2f0091fbf [SCSI] fcoe, libfc: fully makes use of per cpu exch pool and then removes em_lock
1. Updates fcoe_rcv() to queue incoming frames to the fcoe per
   cpu thread on which this frame's exch was originated and simply
   use current cpu for request exch not originated by initiator.
   It is redundant to add this code under CONFIG_SMP, so removes
   CONFIG_SMP uses around this code.

2. Updates fc_exch_em_alloc, fc_exch_delete, fc_exch_find to use
   per cpu exch pools, here fc_exch_delete is rename of older
   fc_exch_mgr_delete_ep since ep/exch are now deleted in pools
   of EM and so brief new name is sufficient and better name.

   Updates these functions to map exch id to their index into exch
   pool using fc_cpu_mask, fc_cpu_order and EM min_xid.
   This mapping is as per detailed explanation about this in
   last patch and basically this is just as lower fc_cpu_mask
   bits of exch id as cpu number and upper bit sum of EM min_xid
   and exch index in pool.

   Uses pool next_index to keep track of exch allocation from
   pool along with pool_max_index as upper bound of exches array
   in pool.

3. Adds exch pool ptr to fc_exch to free exch to its pool in
   fc_exch_delete.

4. Updates fc_exch_mgr_reset to reset all exch pools of an EM,
   this required adding fc_exch_pool_reset func to reset exches
   in pool and then have fc_exch_mgr_reset call fc_exch_pool_reset
   for each pool within each EM for a lport.

5. Removes no longer needed exches array, em_lock, next_xid, and
   total_exches from struct fc_exch_mgr, these are not needed after
   use of per cpu exch pool, also removes not used max_read,
   last_read from struct fc_exch_mgr.

6. Updates locking notes for exch pool lock with fc_exch lock and
   uses pool lock in exch allocation, lookup and reset.

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@suse.de>
2009-09-05 09:47:37 -05:00
Vasu Dev e4bc50bedf [SCSI] fcoe, libfc: adds per cpu exch pool within exchange manager(EM)
Adds per cpu exch pool for these reasons:-

 1. Currently an EM instance is shared across all cpus to manage
    all exches for all cpus. This required em_lock across all
    cpus for an exch alloc, free, lookup and reset each frame
    and that made em_lock expensive, so instead having per cpu
    exch pool with their own per cpu pool lock will likely reduce
    locking contention in fast path for an exch alloc, free and
    lookup.

 2. Per cpu exch pool will likely improve cache hit ratio since
    all frames of an exch will be processed on the same cpu on
    which exch originated.

This patch is only prep work to help in keeping complexity of next
patch low, so this patch only sets up per cpu exch pool and related
helper funcs to be used by next patch. The next patch fully makes
use of per cpu exch pool in all code paths ie. tx, rx and reset.

Divides per EM exch id range equally across all cpus to setup per
cpu exch pool. This division is such that lower bits of exch id
carries cpu number info on which exch originated, later a simple
bitwise AND operation on exch id of incoming frame with fc_cpu_mask
retrieves cpu number info to direct all frames to same cpu on which
exch originated. This required a global fc_cpu_mask and fc_cpu_order
initialized to max possible cpus number nr_cpu_ids rounded up to 2's
power, this will be used in mapping exch id and exch ptr array
index in pool during exch allocation, find or reset code paths.

Adds a check in fc_exch_mgr_alloc() to ensure specified min_xid
lower bits are zero since these bits are used to carry cpu info.

Adds and initializes struct fc_exch_pool with all required fields
to manage exches in pool.

Allocates per cpu struct fc_exch_pool with memory for exches array
for range of exches per pool. The exches array memory is followed
by struct fc_exch_pool.

Adds fc_exch_ptr_get/set() helper functions to get/set exch ptr in
pool exches array at specified array index.

Increases default FCOE_MAX_XID to 0x0FFF from 0x07EF, so that more
exches are available per cpu after above described exch id range
division across all cpus to each pool.

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@suse.de>
2009-09-05 09:47:36 -05:00
Robert Love cd305ce41b [SCSI] libfc: Fix misleading debug statement
The statement reads, "Exchange timed out, notifying the upper layer",
however, this statement is printed whenever the timer is armed. This
is confusing to someone debugging the code because every time an
exchange is initialized, there is an incorrect statement stating that
the timer has already timed out. This patch changes the statement to
read, "Exchange timer armed" which is more accurate.

This patch also adds a debug statement in the timeout handler to
properly indicate that the exchange has timed out.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-05 09:47:32 -05:00
Yi Zou 53fcfbbef5 [SCSI] libfc: Remove page flags check for sglist
I don't believe this check is needed any more in the current kernel, which,
if I understand correctly, is for compound page where only the first page
is supposed to get ref-counted.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:10 -05:00
Yi Zou 537029f8e9 [SCSI] libfc: Remove FC_FRAME_SG_LEN in fc_fcp_send_data
FC_FRAME_SG_LEN is 4 which is too small when offload is enabled. Actually, the
WARN_ON() in fc_fcp_send_data() should be:

	WARN_ON(skb_shinfo(fp_skb(fp))->nr_frags > MAX_SKB_FRAGS);

But since we will not get anything more than 64K anyway, so there is no need
to do this anyway here. Therefore, I am getting rid of FC_FRAME_SG_LEN here
and the WARN_ON here.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:10 -05:00
Vasu Dev d7179680d0 [SCSI] fcoe, libfc: adds offload EM per eth device with only single xid range per EM
Updates fcoe_em_config to allocate a single instance of sharable offload
EM for supported lp->lro_xid per eth device, and then share this EM
for subsequently more lports creation on same eth device (e.g when using
VLAN).

Adds tiny fcoe_oem_match function for offload EM to return true for read
types IO to have read IO exchanges allocated from offload shared EM.

Removes fc_em_alloc_xid function completely which was needed to manage
two xid ranges within a EM, this is not needed any more with allocation
of separate sharable offload EM per eth device. Instead this patch adds
simple xid allocation logic to manage single xid range.

Adds fc_exch_em_alloc with mp->next_xid as cursor to allocate new xid
from single xid range of EM, uses mp->next_xid instead removed mp->last_xid
which slightly increase probability of finding empty xid on exch allocation.

Removes restriction of not allowing use of xid zero along with changing
two xid range change to single xid range.

Makes fc_fcp_ddp_setup calling conditional to only xid allocated from
shared offload EM.

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>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:09 -05:00
Vasu Dev 52ff878c91 [SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor list
Modifies current code to use EM anchor list in EM allocation, EM free,
EM reset, exch allocation and exch lookup code paths.

 1. Modifies fc_exch_mgr_alloc to accept EM match function and then
    have allocated EM added to the lport using fc_exch_mgr_add API
    while also updating EM kref for newly added EM.

 2. Updates fc_exch_mgr_free API to accept only lport pointer instead
    EM and then have this API free all EMs of the lport from EM anchor
    list.

 3. Removes single lport pointer link from the EM, which was used in
    associating lport pointer in newly allocated exchange. Instead have
    lport pointer passed along new exchange allocation call path and
    then store passed lport pointer in newly allocated exchange, this
    will allow a single EM instance to be used across more than one
    lport and used in EM reset to reset only lport specific exchanges.

 4. Modifies fc_exch_mgr_reset to reset all EMs from the EM anchor list
    of the lport, adds additional exch lport pointer (ep->lp) check for
    shared EM case to reset exchange specific to a lport requested reset.

 5. Updates exch allocation API fc_exch_alloc to use EM anchor list and
    its anchor match func pointer. The fc_exch_alloc will walk the list
    of EMs until it finds a match, a match will be either null match
    func pointer or call to match function returning true value.

 6. Updates fc_exch_recv to accept incoming frame on local port using
    only lport pointer and frame pointer without specifying EM instance
    of incoming frame. Instead modified fc_exch_recv to locate EM for the
    incoming frame by matching xid of incoming frame against a EM xid range.
    This change was required to use EM list in libfc Rx path and after this
    change the lport fc_exch_mgr pointer emp is not needed anymore, so
    removed emp pointer.

 7. Updates fnic for removed lport emp pointer and above modified libfc APIs
    fc_exch_recv, fc_exch_mgr_alloc and fc_exch_mgr_free.

 8. Removes exch_get and exch_put from libfc_function_template as these
    are no longer needed with EM anchor list and its match function use.
    Also removes its default function fc_exch_get.

A defect this patch introduced regarding the libfc initialization order in
the fnic driver was fixed by Joe Eykholt <jeykholt@cisco.com>.

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>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:08 -05:00
Robert Love d459b7ea1b [SCSI] libfc: Remove the FC_EM_DBG macro
Currently there is a 1:1 relationship between the lport
and exchange manager. This macro takes an EM as an argument
and determines the lport from it. However, later patches
will use an EM list per lport, so we will no longer have
this 1:1 relationship- this macro must change.

The FC_EM_DBG macro is rarely used. There are four callers,
two can use FC_LPORT_DBG instead and two can be removed
since they're not necessary. This patch makes those changes
and removes the macro.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:08 -05:00
Vasu Dev 96316099ac [SCSI] fcoe, libfc: adds exchange manager(EM) anchor list per lport and related APIs
Adds EM list using a anchor struct fc_exch_mgr_anchor, anchor is used
to allow same EM instance sharing across more than one lport on a eth
device, this implementation is per discussed design posted at
http://www.open-fcoe.org/pipermail/devel/2009-June/002566.html.

The shared EM is required for multiple lports on eth device when
using multiple VLANs or NPIV.

Adds fc_exch_mgr_add API to add a EM to the lport and fc_exch_mgr_del
API to delete previously added EM.

Also adds function fc_exch_mgr_destroy() to destroy allocated EM.
The kref is added to the EM to keep track of EM usage count, the EM is
destroyed when no longer in use upon kref reaching to zero.

The caller can specify match function to fc_exch_mgr_add, this
will be used in determining exchange allocation from its EM or not.

Moved calling of fcoe_em_config below fcoe_libfc_config calling,
so that list head lp->ema_list is initialized before configuring
EM.

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>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:07 -05:00
Joe Eykholt 201e5795b7 [SCSI] libfc: fix: cancel rport retry timer
The timer for rport retries wasn't getting canceled, and
would occasionally go off after the module was unloaded.

Add logic to cancel the timer in fc_rport_work().

Since we cancel the timer before deleting the rdata,
it is no longer necessary to do a get_device() for the pending timer.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:07 -05:00
Joe Eykholt 5f7ea3b7f8 [SCSI] libfc: fc_rport_logoff should not drop the lock
fc_rport_logoff drops the rport lock in order to cancel work
that may be pending.  This is undesirable as the state can
completely change, and the caller may not expect that the
lock could've been dropped.

If there is work pending, it will acquire the rdata mutex and
so we're protected and can change the event from READY to DELETE.
Queue the work only if there is no event already pending.

There were a couple other cases where the state was set to
DELETE and work queued, even though the state may have already
been DELETE.  Fix these using a common function fc_rport_enter_delete().

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:52:06 -05:00