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2009-09-10[SCSI] libfc: don't swap OX_ID and RX_ID when sending BA_RJTJoe Eykholt
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[SCSI] libfc: send GPN_ID in reaction to single-port RSCNs.Joe Eykholt
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[SCSI] libfc: fix handling of incoming Discover Address (ADISC) requestsJoe Eykholt
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[SCSI] libfc: use ADISC to verify rport login stateJoe Eykholt
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[SCSI] libfc: LOGO response code had extraeous enter_rtvJoe Eykholt
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[SCSI] libfc: re-login to remote ports that send us LOGOJoe Eykholt
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[SCSI] libfc: fix rport error handling for login-required and invalid opsJoe Eykholt
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[SCSI] libfc: correctly handle incoming PLOGI request.Joe Eykholt
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[SCSI] libfc: improve debug messages for ELS response handlersJoe Eykholt
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[SCSI] libfc: fix: rport_recv_req needs disc_mutex when calling rport_lookupJoe Eykholt
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[SCSI] libfc: move remote port lookup for ELS requests into fc_rport.c.Joe Eykholt
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[SCSI] libfc: Always reset remote port roles when receiving PRLIRobert Love
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[SCSI] libfc: Initialize fc_rport_identifiers inside fc_rport_createRobert Love
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[SCSI] libfc: don't do discovery before callback is setJoe Eykholt
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[SCSI] libfc: clean up point-to-point discovery code.Joe Eykholt
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[SCSI] libfc: discovery gpn_ft parse bugJoe Eykholt
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[SCSI] libfc: discovery retry should clear pending first.Joe Eykholt
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[SCSI] libfc: fix: empty zone causes endless discovery retries.Joe Eykholt
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[SCSI] libfc: handle discovery failure more correctly.Joe Eykholt
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[SCSI] libfc: rearrange code in fc_disc_gpn_ft_resp()Joe Eykholt
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[SCSI] libfc: discovery restart sequence error fixJoe Eykholt
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[SCSI] libfc: do not log off rports before or after discoveryJoe Eykholt
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[SCSI] libfc: move rport_lookup into fc_rport.cJoe Eykholt
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[SCSI] libfc: change to make remote port callback optionalJoe Eykholt
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[SCSI] libfc: have rport_create do a lookup for pre-existing rports firstJoe Eykholt
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[SCSI] libfc: make rport module maintain the rport listJoe Eykholt
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[SCSI] libfc: simplify fc_lport_rport_callbackJoe Eykholt
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[SCSI] libfc: rport debug messages were printing pointer valuesJoe Eykholt
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[SCSI] libfc: remove unused disc->delay elementJoe Eykholt
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[SCSI] libfc: eliminate disc->eventJoe Eykholt
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[SCSI] libfc: fix rport event race between READY and LOGOJoe Eykholt
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[SCSI] libfc: don't create dummy (rogue) remote portsJoe Eykholt
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[SCSI] libfc: rename rport event CREATED to READYJoe Eykholt
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[SCSI] libfc: rearrange code in fc_rport_workJoe Eykholt
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[SCSI] libfc: make rport structure optionalJoe Eykholt
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[SCSI] libfc: change elsct to use FC_ID instead of rdataJoe Eykholt
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[SCSI] libfc: make fc_rport_priv the primary rport interface.Joe Eykholt
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[SCSI] libfc: change interface for rport_createJoe Eykholt
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[SCSI] libfc: prepare to split off struct fc_rport_priv from fc_rport_libfc_privJoe Eykholt
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>
2009-09-05[SCSI] fcoe, libfc: fully makes use of per cpu exch pool and then removes ↵Vasu Dev
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[SCSI] fcoe, libfc: adds per cpu exch pool within exchange manager(EM)Vasu Dev
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[SCSI] libfc: Fix misleading debug statementRobert Love
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>
2009-08-22[SCSI] libfc: Remove page flags check for sglistYi Zou
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[SCSI] libfc: Remove FC_FRAME_SG_LEN in fc_fcp_send_dataYi Zou
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[SCSI] fcoe, libfc: adds offload EM per eth device with only single xid ↵Vasu Dev
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[SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor listVasu Dev
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[SCSI] libfc: Remove the FC_EM_DBG macroRobert Love
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[SCSI] fcoe, libfc: adds exchange manager(EM) anchor list per lport and ↵Vasu Dev
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[SCSI] libfc: fix: cancel rport retry timerJoe Eykholt
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[SCSI] libfc: fc_rport_logoff should not drop the lockJoe Eykholt
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>