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Author SHA1 Message Date
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
Joe Eykholt
141940548c [SCSI] libfc: rename rport state "NONE" to "DELETE".
State RPORT_ST_NONE was intented to be an invalid state (0), never used.
This was a misguided attempt to be sure it was always initialized.
Having an extra state meaning nothing requires switch statements to
have a case covering that state.

State NONE has been used instead to mean the remote port is being deleted.
Changing the name to RPORT_ST_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
Joe Eykholt
84b05445b9 [SCSI] libfc: fix WARNING from fc_seq_start_next on closed exchanges
We saw periodic messages like:

WARNING: at drivers/scsi/libfc/fc_exch.c:825 fc_seq_start_next+0x30/0x4b

This was due to trying to allocate a sequence in a request handler
when the exchange had been reset.

Delete the WARN_ON.

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
Joe Eykholt
e9ba8b4278 [SCSI] libfc: in fc_lport_destroy, flush rports after turning off link
During an fcoe module unload, we saw a problem where fc_rport_work()
finds the lport has been freed.  The rdata points to an area
containing 0x6b6b6b6b... the pool poison value from kmem_free().

In fcoe_if_destroy() we call fc_fabric_logoff() then fc_lport_destroy().
fc_fabric_logoff() flushes the remote port work, but we're still receiving
requests, and an RSCN or PLOGI arrives which creates more rports.

Note that although the LLD also checks link_up, it doesn't do it
under the lport mutex, so it can deliver frames to
fc_lport_recv_req() even after link_up is cleared.
So, re-check link_up there.

We need to flush the rports by calling disc_stop_final()
after we clear link_up.

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 17:52:05 -05:00
Joe Eykholt
1190d92581 [SCSI] libfc: stop login after fabric logoff
When removing the fcoe module, several lports were being shut down
through fc_lport_fabric_logoff().

Occasionally, one would enter reset state before fc_lport_destroy()
was called, and since link_up was still true, it would log back in.

If we just clear link_up earlier, then we wouldn't be accepting LOGO
requests from other initiators while we are shutting down.

Fix by changing the LOGO response handler to enter DISABLED instead
of RESET.  Add an fc_lport_enter_disabled() function which does
what fc_lport_enter_reset() did, except it doesn't proceed to FLOGI state.

Move the code that was common between fc_lport_enter_reset() and
fc_lport_enter_disabled() into a new fc_lport_reset_locked() function.

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 17:52:05 -05:00
Joe Eykholt
b1d9fd5574 [SCSI] libfc: rename lport NONE state to DISABLED
The state NONE was meant to be invalid, but has been used as
the initial state.  Rename it to be DISABLED, as more descriptive.
Further patches will make it the like the RESET state, except
it won't transition to FLOGI until fc_lport_fabric_login() is called.

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 17:52:04 -05:00
Vasu Dev
a0cc1ecc09 [SCSI] libfc: fix a circular locking warning during sending RRQ
Currently the fc_exch_rrq is called with fc_exch's ex_lock held.
The fc_exch_rrq allocates new exch and that requires taking
ex_lock again after EM lock. This locking order causes warning,
see more details on this warning at :-

 http://www.open-fcoe.org/pipermail/devel/2009-July/003251.html

This patch fixes this by dropping the ex_lock before calling
fc_exch_rrq().

The fc_exch_rrq needs to grab ex_lock lock again to schedule
RRQ retry and in the meanwhile fc_exch_reset could occur before
ex_lock is grabbed inside fc_exch_rrq. So to handle this case,
this patch adds additional check to detect fc_exch_reset after
ex_lock acquired and in case the fc_exch_reset occurred then
abandons the RRQ retry and releases the exch.

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>
2009-07-30 08:50:02 -05:00
Robert Love
7414705ea4 libfc: Add runtime debugging with debug_logging module parameter
This patch adds the /sys/module/libfc/parameters/debug_logging
file to sysfs as a module parameter. It accepts an integer
bitmask for logging. Currently it supports:

   bit
LSB 0 = general libfc debugging
    1 = lport debugging
    2 = disc debugging
    3 = rport debugging
    4 = fcp debugging
    5 = EM debugging
    6 = exch/seq debugging
    7 = scsi logging (mostly error handling)

the other bits are not used at this time.

The patch converts all of the libfc source files to use
these new macros and removes the old FC_DBG macro.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-06-21 11:07:08 -05:00