Commit Graph

151 Commits

Author SHA1 Message Date
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
Steve Ma
30121d14f5 [SCSI] libfc: Check if exchange is completed when receiving a sequence
When a sequence is received in response to an exchange we issued previously,
we should check to see if the exchange has completed. If yes, the sequence
should be discarded. Since the exchange might be still in the completion
process, it should be untouched.

Signed-off-by: Steve Ma <steve.ma@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-06-08 13:29:11 -05:00
Mike Christie
d5e6054a0a [SCSI] libfc: use DID_ERROR when we have internall aborted command
If we aborted a command, because it timed out we should not use
DID_ABORT. It will fail the command right away back to the upper
layer. We want to use something that indicated that the problem
did not complete normally, but it was not a fatal problem.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-06-08 13:29:10 -05:00
Abhijeet Joglekar
a366695592 [SCSI] libfc,fcoe,fnic: Separate rport and lport max retry counts
This allows fnic to configure number of retries for lport and rport
separately.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Acked-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:18 -05:00
Randy Dunlap
b0d428adeb [SCSI] fcoe, libfc: fix function declarations to be ANSI-compliant
Fix function declarations:

drivers/scsi/fcoe/fcoe.c:1356:28: warning: non-ANSI function declaration of function 'fcoe_dev_setup'
drivers/scsi/libfc/fc_rport.c:1293:20: warning: non-ANSI function declaration of function 'fc_setup_rport'
drivers/scsi/libfc/fc_rport.c:1302:23: warning: non-ANSI function declaration of function 'fc_destroy_rport'

[jejb: fixed wrong doc in comment noticed during inspection]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-20 17:21:15 -05:00
Robert Love
a29e7646f4 [SCSI] libfc: Fix compilation warnings with allmodconfig
When building with a .config generated from 'make allmodconfig'
some build warnings are generated. This patch corrects the warnings,
adds a FC_FID_NONE (= 0) enumeration for FC-IDs and cleans up one
variable naming to meet our variable naming conventions. For example,
fc_lport's should be named "lport," not "lp."

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:19:31 -05:00
Abhijeet Joglekar
55c7a60cf0 [SCSI] libfc: whenever queueing delete ev for rport, set state to NONE
When a delete event is queued for an rport, set state to NONE so that no
other processing is done on the rport as it is being removed.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:19:03 -05:00
Abhijeet Joglekar
bbf156697a [SCSI] libfc: Change state to NONE in fc_lport_destroy
After lport_destroy, the local port should not be used again. Transition
to state NONE, any incoming frames or link up should not transition out
of this state since we are deleting exchange table and cleaning up the
local port. Also, mark link as down.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:19:01 -05:00
Abhijeet Joglekar
a0fd2e49ec [SCSI] libfc: During fabric logoff, flush the rport Q after logging off dns port
We want to generate the rport queue event (from the logoff)
before flushing the queue otherwise the event may still be
in the queue when we logoff.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:19:00 -05:00
Abhijeet Joglekar
b4c6f54632 [SCSI] libfc: Track rogue remote ports
Rogue ports are currently not tracked on any list. The only reference
to them is through any outstanding exchanges pending on the rogue ports.
If the module is removed while a retry is set on a rogue port
(say a Plogi retry for instance), this retry is not cancelled because there
is no reference to the rogue port in the discovery rports list. Thus the
local port can clean itself up, delete the exchange pool, and then the
rogue port timeout can fire and try to start up another exchange.

This patch tracks the rogue ports in a new list disc->rogue_rports. Creating
a new list instead of using the disc->rports list keeps remote port code
change to a minimum.

1)  Whenever a rogue port is created, it is immediately added to the
disc->rogue_rports list.

2) When the rogues port goes to ready, it is removed from the rogue list
and the real remote port is added to the disc->rports list

3) The removal of the rogue from the disc->rogue_rports list is done in
the context of the fc_rport_work() workQ thread in discovery callback.

4) Real rports are removed from the disc->rports list like before. Lookup
is done only in the real rports list. This avoids making large changes
to the remote port code.

5) In fc_disc_stop_rports, the rogues list is traversed in addition to the
real list to stop the rogue ports and issue logoffs on them. This way, rogue
ports get cleaned up when the local port goes away.

6) rogue remote ports are not removed from the list right away, but
removed late in fc_rport_work() context, multiple threads can find the same
remote port in the list and call rport_logoff(). Rport_logoff() only
continues with the logoff if port is not in NONE state, thus preventing
multiple logoffs and multiple list deletions.

7) Since the rport is removed from the disc list at a later stage
(in the disc callback), incoming frames can find the rport even if
rport_logoff() has been called on the rport. When rport_logoff() is called,
the rport state is set to NONE, and we are trying to cancel all exchanges
and retries on that port. While in this state, if an incoming
Plogi/Prli/Logo or other frames match the rport, we should not reply
because the rport is in the NONE state. Just drop the frame, since the
rport will be deleted soon in the disc callback (fc_rport_work)

8)  In fc_disc_single(), remove rport lookup and call to fc_disc_del_target.
fc_disc_single() is called from recv_rscn_req() where rport lookup
and rport_logoff is already done.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:18:57 -05:00
Abhijeet Joglekar
76f6804e7e [SCSI] libfc: Do not retry if the new state is not the same as old state
For instance, if there is a Plogi pending (remote port is in Plogi state),
and the state changes to say NONE (because the port is being logged off),
then when the Plogi resp times out, do not start a retry.

This patch partially reverts an earlier patch (libfc: check for err when
recv and state is incorrect), by moving the state check back to before
checking for error. However, if the state does not match, then there is
an additional check to see if its an error ptr or a real frame before
jumping to err or out respectively.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:18:51 -05:00
Abhijeet Joglekar
0d228c0f7f [SCSI] libfc: Hold disc mutex while processing gpn ft resp
gpn_ft_resp processing currently does not hold the discovery lock.
disc_done() thus gets called from gpn_ft_resp or from gpn_ft_parse
without the lock held. This then sets disc->pending to zero or calls
gpn_ft_req() without disc_lock held.

- Hold disc mutex during gpn_ft resp processing
- In disc_done, release the disc mutex while calling lport callback

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:18:48 -05:00
Vasu Dev
9b34ecffd5 [SCSI] fcoe, libfc: add libfcoe module
Just sets up build environment for libfcoe module towards a
libfcoe library for libfc LLDs using FCoE as libfc transport.

Common library code to libfcoe is added in next patch.

Also, updated MODULE_LICENSE from "GPL" string to "GPL v2" for
libfc, libfcoe and fcoe modules to accurately match the licenses.

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>
2009-04-03 09:23:04 -05:00
Robert Love
582b45bc57 [SCSI] fcoe: Use per-CPU kernel function for dev_stats instead of an array
Remove the hotplug creation of dev_stats, we allocate for all possible CPUs
now when we allocate the lport.

v2: Durring the 2.6.30 merge window, before these patches were comitted,
'percpu_ptr' was renamed 'per_cpu_ptr'. This latest update updates this
patch for the name change.

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>
2009-04-03 09:22:58 -05:00
Yi Zou
b277d2aa9a [SCSI] libfc: add support of large receive offload by ddp in fc_fcp
When LLD supports direct data placement (ddp) for large receive of an scsi
i/o coming into fc_fcp, we call into libfc_function_template's ddp_setup()
to prepare for a ddp of large receive for this read I/O. When I/O is complete,
we call the corresponding ddp_done() to get the length of data ddped as well
as to let LLD do clean up.

fc_fcp_ddp_setup()/fc_fcp_ddp_done() are added to setup and complete a ddped
read I/O described by the given fc_fcp_pkt. They would call into corresponding
ddp_setup/ddp_done implemented by the fcoe layer. Eventually, fcoe layer calls
into LLD's ddp_setup/ddp_done provided through net_device

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:15:15 -05:00
Yi Zou
276d68142b [SCSI] libfc: use lso_max for sequence offload
Make sure for large send is supported by LLD in outgoing FCP data, we are only
sending the lso_max a time in one single large send, since that is what
supported by LLD.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:14:33 -05:00
Julia Lawall
aa6cd29b72 [SCSI] libfc: Correct use of ! and &
!ep->esb_stat is either 1 or 0, and the rightmost bit of ESB_ST_COMPLETE is
always 0, making the result of !ep->esb_stat & ESB_ST_COMPLETE always 0.
Thus parentheses around the argument to ! seem needed.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@ expression E; constant C; @@
(
  !E & !C
|
- !E & C
+ !(E & C)
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-12 12:58:13 -05:00
Martin K. Petersen
1c9fbafc8c [SCSI] Remove SUGGEST flags
The SUGGEST_* flags in the SCSI command result have been out of fashion
for a while and we don't actually use them in the error handling.
Remove the remaining occurrences.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-12 12:58:02 -05:00
FUJITA Tomonori
6e7490c73d [SCSI] libfc: fix compile warning
I got the following warnings on IA64:

drivers/scsi/libfc/fc_lport.c: In function 'fc_lport_recv_flogi_req':
drivers/scsi/libfc/fc_lport.c:788: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'u64'
drivers/scsi/libfc/fc_lport.c:792: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'u64'
scsi/libfc/fc_rport.c: In function 'fc_rport_recv_plogi_req':
/home/fujita/git/linux-2.6/drivers/scsi/libfc/fc_rport.c:968: warning: format '%llx' expects type 'long long unsigned int', but argument 4 has type 'u64'

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-12 12:57:56 -05:00
Yi Zou
422819cfa3 [SCSI] libfc: do not change the fh_rx_id of a recevied frame
We shouldn't be altering inbound frames.

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>
2009-03-10 09:06:36 -05:00
Robert Love
b2ab99c9a3 [SCSI] libfc, fcoe: Cleanup function formatting and minor typos
1) There were a few functions with a strange layout, i.e. all
   arguments on the second line, when not necessary.

   Where ever possible I moved the return value to the same line
   as the function name. However, when the line was too long
   to have a single argument on the same line I moved the
   return value to above line. For example:

   <short return> <function name>(<arg 1>, <arg2>)

   and

   <very long return value>
   <function name>(<arg1>,
		   <arg2>)

2) Removed one extra whitespace line

3) Fixed two typos

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:05:09 -05:00
Robert Love
34f42a070f [SCSI] libfc, fcoe: Fix kerneldoc comments
1) Added '()' for function names in kerneldoc comments

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

3) Removed incorrect linebreaks in kerneldoc comments where found

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

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:40:06 -06:00
Chris Leech
6755db1cd4 [SCSI] libfc: rport retry on LS_RJT from certain ELS
This allows any rport ELS to retry on LS_RJT.

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

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

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:39:34 -06:00
Vasu Dev
bc0e17f691 [SCSI] libfc, fcoe: fixed locking issues with lport->lp_mutex around lport->link_status
The fcoe_xmit could call fc_pause in case the pending skb queue len is larger
than FCOE_MAX_QUEUE_DEPTH, the fc_pause was trying to grab lport->lp_muex to
change lport->link_status and that had these issues :-

1. The fcoe_xmit was getting called with bh disabled, thus causing
"BUG: scheduling while atomic" when grabbing lport->lp_muex with bh disabled.

2. fc_linkup and fc_linkdown function calls lport_enter function with
lport->lp_mutex held and these enter function in turn calls fcoe_xmit to send
lport related FC frame, e.g. fc_linkup => fc_lport_enter_flogi to send flogi
req. In this case grabbing the same lport->lp_mutex again in fc_puase from
fcoe_xmit would cause deadlock.

The lport->lp_mutex was used for setting FC_PAUSE in fcoe_xmit path but
FC_PAUSE bit was not used anywhere beside just setting and clear this
bit in lport->link_status, instead used a separate field qfull in fc_lport
to eliminate need for lport->lp_mutex to track pending queue full condition
and in turn avoid above described two locking issues.

Also added check for lp->qfull in fc_fcp_lport_queue_ready to trigger
SCSI_MLQUEUE_HOST_BUSY when lp->qfull is set to prevent more scsi-ml cmds
while lp->qfull is set.

This patch eliminated FC_LINK_UP and FC_PAUSE and instead used dedicated
fields in fc_lport for this, this simplified all related conditional
code.

Also removed fc_pause and fc_unpause functions and instead used newly added
lport->qfull directly in fcoe.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:37:49 -06:00
Vasu Dev
a7e84f2b83 [SCSI] libfc: fixed a soft lockup issue in fc_exch_recv_abts
The fc_seq_start_next grabs ep->ex_lock but this lock was already held here,
so instead called fc_seq_start_next_locked to avoid soft lockup.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:37:23 -06:00
Vasu Dev
78342da368 [SCSI] libfc: handle RRQ exch timeout
Cleanup exchange held due to RRQ when RRQ exch times out, in this case the
ABTS is already done causing RRQ req therefore proceeding with cleanup in
fc_exch_rrq_resp should be okay to restore exch resource.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:36:56 -06:00
Abhijeet Joglekar
571f824c3c [SCSI] libfc: when rport goes away (re-plogi), clean up exchanges to/from rport
When a rport goes away, libFC does a plogi which will reset exchanges
    at the rport. Clean exchanges at our end, both in transport and libFC.
    If transport hooks into exch_mgr_reset, it will call back into
    fc_exch_mgr_reset() to clean up libFC exchanges.

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

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

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

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

The framing library frames ELS and CT commands.

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

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

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

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

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