Commit Graph

31 Commits (a70757ba9a3719f99760713c3b72134b21016c6e)

Author SHA1 Message Date
Vasu Dev 4ae1e19f25 [SCSI] libfc: fix an issue of pending exch/es after i/f destroyed or rmmod fcoe
All exches must be freed before its EM mempool destroyed in this
case but currently some exches could be still pending in their
scheduled delayed work after EM mempool is destroyed causing
this issue discussed and reported in this latest email thread:-

 http://www.open-fcoe.org/pipermail/devel/2009-October/004788.html

This patch fixes this issue by adding dedicated work queue thread
fc_exch_workqueue for exch delayed work and then flush this work
queue before destroying EM mempool.

The cancel_delayed_work_sync cannot be called during final
fc_exch_reset due to lport and exch locking ordering, so removes
related comment block not relevant any more with this patch.

Reported-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@suse.de>
2009-12-04 12:01:26 -06:00
Robert Love 3a3b42bf89 [SCSI] libfc: Formatting cleanups across libfc
This patch makes a variety of cleanup changes to all libfc files.

This patch adds kernel-doc headers to all functions lacking them
and attempts to better format existing headers. It also add kernel-doc
headers to structures.

This patch ensures that the current naming conventions for local ports,
remote ports and remote port private data is upheld in the following
manner.

struct               instance (i.e. variable name)
--------------------------------------------------
fc_lport                      lport
fc_rport                      rport
fc_rport_libfc_priv           rpriv
fc_rport_priv                 rdata

I also renamed dns_rp and ptp_rp to dns_rdata and ptp_rdata
respectively.

I used emacs 'indent-region' and 'tabify' on all libfc files
to correct spacing alignments.

I feel sorry for anyone attempting to review this patch.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:01:07 -06:00
Chris Leech 174e1ebffd [SCSI] libfc: add some generic NPIV support routines to libfc
Adds a function to create a new VN_Port instances, which share the EM
list with the N_Port, VN_Port lookup by fabric ID when responding to a new
request (otherwise the exchange lookup from the N_Ports EM list is trusted to
return an exchange with a cached lport value for the correct VN_Port),
a pointer to a fc_vport structure for VN_Ports, and flags to indicate if an
N_Port supports NPIV and if the switch/fabric allows it.

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@suse.de>
2009-12-04 12:00:56 -06:00
Robert Love 8866a5d907 [SCSI] libfc: Add libfc/fc_libfc.[ch] for libfc internal routines
include/scsi/libfc.h is currently loaded with common code
shared between libfc's sub-modules as well as shared between
libfc and fcoe. Previous patches attempted to move out
non-common code. This patch creates two files for common
libfc routines that will not be shared with fcoe, fnic or
any other LLDs.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:00:55 -06:00
Robert Love 1a7b75ae71 [SCSI] libfc: Move non-common routines and prototypes out of libfc.h
This patch moves all non-common routines and function prototypes
out of libfc.h and into the appropriate .c files. It makes these
routines 'static' when necessary and removes any unnecessary EXPORT_SYMBOL
statements.

A result of moving the fc_exch_seq_send, fc_seq_els_rsp_send, fc_exch_alloc
and fc_seq_start_next prototypes out of libfc.h is that they were no longer
being imported into fc_exch.c when libfc.h was included. This caused errors
where routines in fc_exch.c were looking for undefined symbols. To fix this
this patch reorganizes fc_seq_alloc, fc_seq_start_next and
fc_seq_start_next_locked. This move also made it so that
fc_seq_start_next_locked did not need to be prototyped at the top of
fc_exch.c.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:00:53 -06:00
Vasu Dev e95147d8fa [SCSI] libfc: removes unused disc_work and ex_list
Reported-by: Alex Lyakas <alexl@mellanox.co.il>
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>
2009-12-04 12:00:31 -06:00
Vasu Dev 3f127ad97a [SCSI] libfc: adds missing exch release for accepted RRQ
Adds missing exch release when RRQ is accepted by calling
fc_seq_ls_acc. Adds common exch release for fc_exch_els_rrq
by use of out label.

Reported-by: Alex Lyakas <alexl@mellanox.co.il>
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>
2009-12-04 12:00:30 -06:00
Vasu Dev 89f19a59de [SCSI] libfc: removes initializing fc_cpu_order and fc_cpu_mask per lport
Initializing these libfc globals per lport could mess up exch
allocation/free for existing lport.

So this patch moves their initialization to fc_setup_exch_mgr
so that these globals gets initialized only once for libfc.

Reported-by: Alex Lyakas <alexl@mellanox.co.il>
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>
2009-12-04 12:00:29 -06:00
Robert Love 473e28563f [SCSI] libfc, fcoe: Don't EXPORT_SYMBOLS unnecessarily
These are a few functions that were not used by other
modules. They did not need to be exported so this patch
removes the EXPORT_SYMBOLS call for each.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:00:24 -06:00
Joe Eykholt 1d490ce33e [SCSI] libfc: don't swap OX_ID and RX_ID when sending BA_RJT
I saw an lport debug message from the exchange manager saying:
"lport  70500: Received response for out of range oxid:ffff"

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

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

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:08:03 -05:00
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
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 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 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
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
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
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
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 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 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