Commit Graph

232 Commits

Author SHA1 Message Date
Sagi Grimberg 55e51eda48 SCSI/libiscsi: Add check_protection callback for transports
iSCSI needs to be at least aware that a task involves protection
information.  In case it does, after the transaction completed libiscsi
will ask the transport to check the protection status of the
transaction.

Unlike transport errors, DIF errors should not prevent successful
completion of the transaction from the transport point of view, but
should be escelated to scsi mid-layer when constructing the scsi
result and sense data.

check_protection routine will return the ascq corresponding to the DIF
error that occured (or 0 if no error happened).

return ascq:
- 0x1: GUARD_CHECK_FAILED
- 0x2: APPTAG_CHECK_FAILED
- 0x3: REFTAG_CHECK_FAILED

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
2014-03-17 22:33:58 -07:00
Mike Christie 46a84c6516 [SCSI] libiscsi: remove unneeded queue work when max_cmdsn is increased
iscsi_queuecommand will only take in commands that can fit in the
current window. So, if a command is on the cmdqueue then it can
fit in the current window. If a command is on the mgmtqueue, then
we are setting the immediate bit so they will also fit in the
window. As a result, we never need to to do a iscsi_conn_queue_work
when the maxCmdSn is increased.

What should happen is that a command will complete the window will
be increased, then the scsi layer will send us more commands by
running the scsi_device queues.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:19:18 -07:00
Shlomo Pongratz 659743b02c [SCSI] libiscsi: Reduce locking contention in fast path
Replace the session lock with two locks, a forward lock and
a backwards lock named frwd_lock and back_lock respectively.

The forward lock protects resources that change while sending a
request to the target, such as cmdsn, queued_cmdsn, and allocating
task from the commands' pool with kfifo_out.

The backward lock protects resources that change while processing
a response or in error path, such as cmdsn_exp, cmdsn_max, and
returning tasks to the commands' pool with kfifo_in.

Under a steady state fast-path situation, that is when one
or more processes/threads submit IO to an iscsi device and
a single kernel upcall (e.g softirq) is dealing with processing
of responses without errors, this patch eliminates the contention
between the queuecommand()/request response/scsi_done() flows
associated with iscsi sessions.

Between the forward and the backward locks exists a strict locking
hierarchy. The mutual exclusion zone protected by the forward lock can
enclose the mutual exclusion zone protected by the backward lock but not
vice versa.

For example, in iscsi_conn_teardown or in iscsi_xmit_data when there is
a failure and __iscsi_put_task is called, the backward lock is taken while
the forward lock is still taken. On the other hand, if in the RX path a nop
is to be sent, for example in iscsi_handle_reject or __iscsi_complete_pdu
than the forward lock is released and the backward lock is taken for the
duration of iscsi_send_nopout, later the backward lock is released and the
forward lock is retaken.

libiscsi_tcp uses two kernel fifos the r2t pool and the r2t queue.

The insertion and deletion from these queues didn't corespond to the
assumption taken by the new forward/backwards session locking paradigm.

That is, in iscsi_tcp_clenup_task which belongs to the RX (backwards)
path, r2t is taken out from r2t queue and inserted to the r2t pool.
In iscsi_tcp_get_curr_r2t which belong to the TX (forward) path, r2t
is also inserted to the r2t pool and another r2t is pulled from r2t
queue.

Only in iscsi_tcp_r2t_rsp which is called in the RX path but can requeue
to the TX path, r2t is taken from the r2t pool and inserted to the r2t
queue.

In order to cope with this situation, two spin locks were added,
pool2queue and queue2pool. The former protects extracting from the
r2t pool and inserting to the r2t queue, and the later protects the
extracing from the r2t queue and inserting to the r2t pool.

Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
[minor fix up to apply cleanly and compile fix]
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:19:18 -07:00
Vaughan Cao e5dbbe273f [SCSI] iscsi: fix wrong order of opcode and itt in iscsi_handle_reject prompt
This patch makes reject messages show right value for opcode and itt, which
is converse previously.

Signed-off-by: Vaughan Cao <vaughan.cao@oracle.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:19:00 -07:00
Adheer Chandravanshi ae56ff4084 [SCSI] libiscsi: Add local_ipaddr parameter in iscsi_conn struct
Add local_ipaddr param and support get/set operations on it.

Signed-off-by: Adheer Chandravanshi <adheer.chandravanshi@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-12-19 20:56:26 -08:00
Or Gerlitz 6a06a4b8cf [SCSI] IB/iser: Add Discovery support
To run discovery over iSER we need to advertize the CAP_TEXT_NEGO capability
towards user space. Also need to make sure the login RX buffer is posted when
SendTargets TEXT PDUs are sent. For that end, we use a setting of the
ISCSI_PARAM_DISCOVERY_SESS iscsi param as an indication that this is
discovery session.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-26 18:53:49 +04:00
Adheer Chandravanshi 5f09e1f310 [SCSI] libiscsi: Add missing prints for session and connection sysfs attrs
Signed-off-by: Adheer Chandravanshi <adheer.chandravanshi@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-23 13:46:31 -04:00
Adheer Chandravanshi 9a2307b144 [SCSI] libiscsi: Add a missing break statement
Signed-off-by: Adheer Chandravanshi <adheer.chandravanshi@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-23 13:45:30 -04:00
Adheer Chandravanshi f8525eb4cf [SCSI] libiscsi: Exporting new attrs for iscsi session and connection in sysfs
Signed-off-by: Adheer Chandravanshi <adheer.chandravanshi@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-23 13:10:16 -04:00
Eddie Wai 3b9373e95a [SCSI] libiscsi: Added new boot entries in the session sysfs
This is the kernel part of the modification to extract the net params
from the ibft sysfs to the iface struct used for the connection
request upon sync_session in the open-iscsi util.

Three new session sysfs params are defined:
boot_root - holds the name of the /sys/firmware/ibft or iscsi_rootN
boot_nic  - holds the ethernetN name
boot_target - holds the targetN name

Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-06-26 18:04:11 -07:00
Masatake YAMATO 1fc2b00fba [SCSI] libiscsi: avoid unnecessary multiple NULL assignments
In iscsi_free_task, NULL is assigned to task->sc twice: before and
after kfifo_in invocatoin. Allocating and freeing iscsi_task are guarded
with session->lock, so multiple NULL assignments cause no trouble. But
people reading the source code may be confused.

The second NULL assignment comes from commit:

    3e5c28ad03

It seems that the line after kfifo_in invocation was introduced
accidentally.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-11 16:54:01 -07:00
Adheer Chandravanshi adaf6990dd [SCSI] libiscsi: export function iscsi_switch_str_param
Signed-off-by: Adheer Chandravanshi <adheer.chandravanshi@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-11 15:26:48 -07:00
Mike Christie e3d338a536 [SCSI] libiscsi: fix cmd timeout/completion race
If the driver/lib has called scsi_done and cleaned up internally but
scsi layer has not yet called blk_mark_rq_complete when the command
times out we hit a problem if the timeout code calls blk_mark_rq_complete first.
When the time out code calls into the driver we were returning
BLK_EH_RESET_TIMER and that causes the timeout code to just call
us again later.

We need to be calling BLK_EH_HANDLED so the timeout code can complete
the completion process because it had called blk_mark_rq_complete
on the command and now owns its processing.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 08:09:00 -06:00
Mike Christie 1304be5fe0 [SCSI] libiscsi_tcp: fix max_r2t manipulation
Problem description from Xi Wang:
A large max_r2t could lead to integer overflow in subsequent call to
iscsi_tcp_r2tpool_alloc(), allocating a smaller buffer than expected
and leading to out-of-bounds write.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 08:09:00 -06:00
Vikas Chaudhary 3c5c480118 [SCSI] libiscsi: Added support to show targetalias in sysfs
sysfs patch to view target alias:
  /sys/class/iscsi_session/session*/targetalias

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 08:08:54 -06:00
Paul Gortmaker acf3368ffb scsi: Fix up files implicitly depending on module.h inclusion
The module.h header was implicitly present everywhere, so files
with no explicit include of the module infrastructure would build
anyway.  We are now removing the implicit include, and so we need
to call out the module.h file that we need explicitly.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:24 -04:00
Mike Christie 5431ae267a [SCSI] libiscsi: don't bugon when if user sets markers
libiscsi does not support markers and if someone tries
to set them the driver does a BUG(). There is not need
to be that extreme. Just return -ENOSYS.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-27 08:36:19 -06:00
Nicholas Bellinger 8304bbceee iscsi: Add Serial Number Arithmetic LT and GT into iscsi_proto.h
This patch moves the iscsi_sna_lt() and iscsi_sna_lte(), along with
iscsi_sna_gt() and iscsi_sna_gte() from iscsi_target_mod into
static inlines inside of include/scsi/iscsi_proto.h

This patch also includes the ISCSI_HDR_LEN and ISCSI_CRC_LEN
definitions.

(Added JesperJ simpliciation for iscsi_sna_* usage)

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-07-25 07:48:08 +00:00
Andy Grover 55bdabdf41 iscsi: Use struct scsi_lun in iscsi structs instead of u8[8]
struct scsi_lun is also just a struct with an array of 8 octets (64 bits)
but using it instead in iscsi structs lets us call scsilun_to_int
without a cast, and also lets us copy it using assignment, instead of
memcpy().

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-07-25 07:47:59 +00:00
Nicholas Bellinger 123521830c iscsi: Resolve iscsi_proto.h naming conflicts with drivers/target/iscsi
This patch renames the following iscsi_proto.h structures to avoid
namespace issues with drivers/target/iscsi/iscsi_target_core.h:

*) struct iscsi_cmd -> struct iscsi_scsi_req
*) struct iscsi_cmd_rsp -> struct iscsi_scsi_rsp
*) struct iscsi_login -> struct iscsi_login_req

This patch includes useful ISCSI_FLAG_LOGIN_[CURRENT,NEXT]_STAGE*,
and ISCSI_FLAG_SNACK_TYPE_* definitions used by iscsi_target_mod, and
fixes the incorrect definition of struct iscsi_snack to following
RFC-3720 Section 10.16. SNACK Request.

Also, this patch updates libiscsi, iSER, be2iscsi, and bn2xi to
use the updated structure definitions in a handful of locations.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-07-25 07:18:45 +00:00
Mike Christie 00f3708e6e [SCSI] libiscsi: add helper to convert addr to string
This adds a helper to convert a addr struct to
a string. This will be used by the drivers in
the next patches.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-24 12:41:08 -05:00
Mike Christie bfcf72e442 [SCSI] libiscsi: use bh locking instead of irq with session lock
The session lock is taken in threads, timers, and bottom halves
like softirqs and tasklets. All the code but
iscsi_conn/session_failure take the session lock with the spin_lock_bh
call. This was done because I thought some offload drivers
would be calling these functions from a irq. They never did,
so this patch has iscsi_conn/session_failure use the bh
locking.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-12-31 09:53:09 -06:00
Mike Christie f41d472179 [SCSI] libiscsi: do not take host lock in queuecommand
iscsi_tcp, ib_iser, cxgb*, be2iscsi and bnx2i do not use
the host lock and do not take the session lock against
a irq, so this patch drops the DEF_SCSI_QCMD use. Instead
we just take the session lock and disable bhs.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-12-31 09:52:44 -06:00
Mike Christie df4da5cdfc [SCSI] libiscsi: add more informative failure message during iscsi scsi eh
This adds a more informative error code and message
for the iscsi scsi eh session drop paths. This allows
you to distinguish if the session was dropped due to
a connection failure vs the iscsi layer dropping
the session due to scsi eh failure processing.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-12-31 09:51:54 -06:00
Eddie Wai 8eea2f55a6 [SCSI] bnx2i: Added fix for NOP-Out response panic from unsolicited NOP-In
The patch fixes the following situations where NOP-Out pkt is called for:
- local unsolicited NOP-Out requests (requesting no NOP-In response)
- local NOP-Out responses to unsolicited NOP-In requests

kernel panic is observed due to double session spin_lock requests; one in the
bnx2i_process_nopin_local_cmpl routine in bnx2i_hwi.c and the other in the
iscsi_put_task routine in libiscsi.c

The proposed fix is to export the currently static __iscsi_put_task() routine
and have bnx2i call it directly instead of the iscsi_put_task() routine which
holds the session spin lock.

Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Reviewed-by: Anil Veerabhadrappa <anilgv@broadcom.com>
Acked-by: Benjamin Li <benli@broadcom.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-12-21 12:24:10 -06:00
Jeff Garzik f281233d3e SCSI host lock push-down
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-16 13:33:23 -08:00
Mike Christie 96b1f96dca [SCSI] libiscsi: regression: fix header digest errors
This fixes a regression introduced with this commit:

commit d3305f3407
Author: Mike Christie <michaelc@cs.wisc.edu>
Date:   Thu Aug 20 15:10:58 2009 -0500

    [SCSI] libiscsi: don't increment cmdsn if cmd is not sent

in 2.6.32.

When I moved the hdr->cmdsn after init_task, I added
a bug when header digests are used. The problem is
that the LLD may calculate the header digest in init_task,
so if we then set the cmdsn after the init_task call we
change what the digest will be calculated by the target.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-05-02 11:16:50 -04:00
Linus Torvalds 7da23b86e1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] qla1280: retain firmware for error recovery
  [SCSI] attirbute_container: Initialize sysfs attributes with sysfs_attr_init
  [SCSI] advansys: fix regression with request_firmware change
  [SCSI] qla2xxx: Updated version number to 8.03.02-k2.
  [SCSI] qla2xxx: Prevent sending mbx commands from sysfs during isp reset.
  [SCSI] qla2xxx: Disable MSI on qla24xx chips other than QLA2432.
  [SCSI] qla2xxx: Check to make sure multique and CPU affinity support is not enabled at the same time.
  [SCSI] qla2xxx: Correct vp_idx checking during PORT_UPDATE processing.
  [SCSI] qla2xxx: Honour "Extended BB credits" bit for CNAs.
  [SCSI] scsi_transport_fc: Make sure commands are completed when rport is offline
  [SCSI] libiscsi: Fix recovery slowdown regression
2010-04-05 15:37:12 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Mike Christie 4ae0a6c15e [SCSI] libiscsi: Fix recovery slowdown regression
We could be failing/stopping a connection due to libiscsi starting
recovery/cleanup, but the xmit path or scsi eh thread path
could be dropping the connection at the same time.

As a result the session->state gets set to failed instead of in
recovery. We end up not blocking the session
and so the replacement timeout never gets started and we only end up
failing the IO when scsi_softirq_done sees that the
cmd has been running for (cmd->allowed + 1) * rq->timeout secs.

We used to fail the IO right away so users are seeing a long
delay when using dm-multipath. This problem was added in
2.6.28.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-03-27 15:02:48 -04:00
Jayamohan Kallickal 309ce156aa [SCSI] libiscsi: Make iscsi_eh_target_reset start with session reset
The iscsi_eh_target_reset has been modified to attempt
target reset only. If it fails, then iscsi_eh_session_reset
will be called.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jayamohan Kallickal <jayamohank@serverengines.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-03-03 17:39:04 +05:30
Mike Christie 92ed4d6993 [SCSI] libiscsi: reset cmd timer if cmds are making progress
This patch resets the cmd timer if cmds started before
the timedout command are making progress. The idea is
that the cmd probably timed out because we are trying
to exeucte too many commands. If it turns out that the
device the IO timedout on was bad or the cmd just got
screwed up but other IO/devs were ok then we will
will figure this out when the cmds ahead of the timed
out one complete ok.

This also fixes a bug where we were sort of detecting
this by setting the last_timeout and last_xfer to the
same value when the task was allocated. That caught
the case where we never got to send any IO for it. However,
if the problem had started right before we started the
new task, then we were forced to wait an extra cmd
timeout seconds to start the scsi eh.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-02-17 13:40:10 -06:00
Stefani Seibold 7acd72eb85 kfifo: rename kfifo_put... into kfifo_in... and kfifo_get... into kfifo_out...
rename kfifo_put...  into kfifo_in...  to prevent miss use of old non in
kernel-tree drivers

ditto for kfifo_get...  -> kfifo_out...

Improve the prototypes of kfifo_in and kfifo_out to make the kerneldoc
annotations more readable.

Add mini "howto porting to the new API" in kfifo.h

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:56 -08:00
Stefani Seibold e64c026dd0 kfifo: cleanup namespace
change name of __kfifo_* functions to kfifo_*, because the prefix __kfifo
should be reserved for internal functions only.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:56 -08:00
Stefani Seibold c1e13f2567 kfifo: move out spinlock
Move the pointer to the spinlock out of struct kfifo.  Most users in
tree do not actually use a spinlock, so the few exceptions now have to
call kfifo_{get,put}_locked, which takes an extra argument to a
spinlock.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:56 -08:00
Stefani Seibold 4546548789 kfifo: move struct kfifo in place
This is a new generic kernel FIFO implementation.

The current kernel fifo API is not very widely used, because it has to
many constrains.  Only 17 files in the current 2.6.31-rc5 used it.
FIFO's are like list's a very basic thing and a kfifo API which handles
the most use case would save a lot of development time and memory
resources.

I think this are the reasons why kfifo is not in use:

 - The API is to simple, important functions are missing
 - A fifo can be only allocated dynamically
 - There is a requirement of a spinlock whether you need it or not
 - There is no support for data records inside a fifo

So I decided to extend the kfifo in a more generic way without blowing up
the API to much.  The new API has the following benefits:

 - Generic usage: For kernel internal use and/or device driver.
 - Provide an API for the most use case.
 - Slim API: The whole API provides 25 functions.
 - Linux style habit.
 - DECLARE_KFIFO, DEFINE_KFIFO and INIT_KFIFO Macros
 - Direct copy_to_user from the fifo and copy_from_user into the fifo.
 - The kfifo itself is an in place member of the using data structure, this save an
   indirection access and does not waste the kernel allocator.
 - Lockless access: if only one reader and one writer is active on the fifo,
   which is the common use case, no additional locking is necessary.
 - Remove spinlock - give the user the freedom of choice what kind of locking to use if
   one is required.
 - Ability to handle records. Three type of records are supported:
   - Variable length records between 0-255 bytes, with a record size
     field of 1 bytes.
   - Variable length records between 0-65535 bytes, with a record size
     field of 2 bytes.
   - Fixed size records, which no record size field.
 - Preserve memory resource.
 - Performance!
 - Easy to use!

This patch:

Since most users want to have the kfifo as part of another object,
reorganize the code to allow including struct kfifo in another data
structure.  This requires changing the kfifo_alloc and kfifo_init
prototypes so that we pass an existing kfifo pointer into them.  This
patch changes the implementation and all existing users.

[akpm@linux-foundation.org: fix warning]
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:55 -08:00
Mike Christie 1796e72291 [SCSI] libiscsi: hook into ramp up/down handling
It is rare to get a queue full with iscsi, because targets seem to
just reduce the iscsi cmd window. However, there is at least
one iscsi target that will throw a queue full when overloaded.
This hooks the iscsi code in to the ramp up/down code, so we
can handle it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:01:39 -06:00
Mike Christie 3fe5ae8b4c [SCSI] libiscsi: add warm target reset tmf support
This implements warm target reset tmf support for
the scsi-ml target reset callback. Previously we would
just drop the session in that callback. This patch will
now try a target reset and if that fails drop the session.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:01:36 -06:00
Mike Christie 5d12c05e29 [SCSI] libiscsi: Check TMF state before sending PDU
Patch and mail from both MikeC and HannesR:

Before we're trying to send a PDU we have to check whether a TMF
is active. If so and if the PDU will be affected by the TMF
we should allow only Data-out PDUs to be sent.

If fast_abort is set, no Data-out PDUs will be sent while
a LUN reset is being processed for a affected LUN.

fast_abort is now ingored during a ABORT TASK tmf. We will not
send any Data-outs for a task if the task is being aborted.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:01:36 -06:00
Mike Christie 4f704dc032 [SCSI] libiscsi: fix login/text checks in pdu injection code
For some reason we used to check for the the immediate bit
set and the opcocde in many places instead of just masking
the opcode. In the passthrough code this is a problem
because userspace may or may not have set the immediate bit
and it does not have to. This fixes up the opcode checks
in the passthrough code, so we mask off the opcode then
check against the iscsi proto definition like is done in
other places.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:01:35 -06:00
Mike Christie e881a172da [SCSI] modify change_queue_depth to take in reason why it is being called
This patch modifies scsi_host_template->change_queue_depth so that
it takes an argument indicating why it is being called. This will be
used so that if a LLD needs to do some extra processing when
handling queue fulls or later ramp ups, it can do so.

This is a simple port of the drivers setting a change_queue_depth
callback. In the patch I just have these LLDs adjust the queue depth
if the user was requesting it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>

[Vasu.Dev: v2
	Also converted pmcraid_change_queue_depth and then verified
all modules compile  using "make allmodconfig" for any new build
warnings on X86_64.

	Updated original description after combing two original
patches from Mike to make this patch git bisectable.]
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
[jejb: fixed up 53c700]
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:00:41 -06:00
Jayamohan Kallickal b8b9e1b812 [SCSI] libiscsi: iscsi_session_setup to allow for private space
This patch contains changes that allow iscsi_session_setup
to allocate private space for LLD's

Signed-off-by: Jayamohan Kallickal <jayamohank@serverengines.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-10-02 14:01:39 -05:00
Mike Christie 661134ad37 [SCSI] libiscsi, bnx2i: make bound ep check common
bnx2i currently has a check for if a ep is properly bound, so if
iscsi_queuecommand/xmit_task is called while there is no ep
we will not queue IO.

be2iscsi sends IO from queuecommand/xmit_task like how bnx2i does
and needs a similar test. This patch has us just use the suspend_bit
test for this.

When ep_poll has succeeed iscsid will call conn_bind, the LLD will
then call iscsi_conn_bind which will clear the suspend bit.
When ep_disconnect is called (or if there is a conn error) we set
the suspend bit. For the ep_disconnect case I am adding a helper
in this patch that will take the session lock to make sure
iscsi_queuecommand/xmit_task is not running and it will set
the suspend bit.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jayamohan Kallickal <jayamohank@serverengines.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-12 09:35:33 -05:00
Mike Christie 4c0ba5d259 [SCSI] libiscsi: add completion function for drivers that do not need pdu processing
beiscsi does not need the iscsi scsi cmd processing. It does not
even get this info on the completion path. This adds a function
to just update the sequencing numbers and complete a task.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jayamohan Kallickal <jayamohank@serverengines.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-12 09:35:33 -05:00
Mike Christie 70b31c152d [SCSI] libiscsi, iscsi_tcp: check suspend bit before each call to xmit_task
If we had multiple tasks on the cmd or requeue  lists, and iscsi_tcp
returns a error, the write_space function can still run and queue
iscsi_data_xmit. If it was a legetimate problem and iscsi_conn_failure
was run but we raced and iscsi_data_xmit was run first it could miss
the suspend bit checks, and start trying to send data again and hit
another timeout. A similar problem is present when using cxgb3i.

This has libiscsi check the suspend bit before calling the xmit
task callout, so we at least do not try sending multiple tasks
(one could be sent).

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-05 09:42:48 -05:00
Mike Christie 8afa1439fc [SCSI] libiscsi: handle immediate command rejections
If we sent multiple pdus as immediate the target could be
rejecting some and we have just been dropping the rejection
notification. This adds code to handle nop-out rejections,
so if a nop-out was sent as a ping and rejected we do not
mark the connection bad. Instead we just clean up the timers
since we have pdu making a rount trip we know the connection
is good.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-05 09:42:42 -05:00
Mike Christie d3305f3407 [SCSI] libiscsi: don't increment cmdsn if cmd is not sent
We increment session->cmdsn at the top of iscsi_prep_scsi_cmd_pdu, but
if the prep  ecb or prep bidi or init_task calls fails then we leave the
session->cmdsn incremented. This moves the cmdsn manipulation to the end
of the function when we know it has succeeded.

It also adds a session->cmdsn--; in queuecommand for if a driver like
bnx2i tries to send a a task from that context but it fails. We do not
have to do this in the xmit thread context because that code will retry
the same task if the initial call fails.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-05 09:42:41 -05:00
Mike Christie 6187c24208 [SCSI] libiscsi: disable bh in and abort handler.
The session lock can be held in the scsi eh thread or the completion
paths run from the net softirq. This disables bhs in iscsi_eh_abort when
taking the session lock.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-07-30 08:49:59 -05:00
Erez Zilber bd2199d417 libiscsi: add conn and scsi eh log debug flags
Allow the user to control the debug logs in libiscsi. We will now
have a module param for connection, session & error handling.

[Mike Christie - Fixed up to compile on current code and added
missing ISCSI_DBG_EH conversions]

Signed-off-by: Erez Zilber <erezzi.list@gmail.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-06-21 10:52:41 -05:00
Mike Christie d355e57d58 libiscsi: don't run scsi eh if iscsi task is making progress
If we are sending or receiving data for the task successfully do
not run the scsi eh, because we know the task is making progress.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-06-21 10:52:39 -05:00
Mike Christie 4421c9ebee [SCSI] libiscsi: add debug printks for iscsi command completion path
This patch just adds some debug statements for the abort
and completion paths.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:13 -05:00
Mike Christie b3cd5050bf [SCSI] libiscsi: add task aborted state
If a task did not complete normally due to a TMF, libiscsi will
now complete the task with the state ISCSI_TASK_ABRT_TMF. Drivers
like bnx2i that need to free resources if a command did not complete normally
can then check the task state. If a driver does not need to send
a special command if we have dropped the session then they can check
for ISCSI_TASK_ABRT_SESS_RECOV.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:13 -05:00
Mike Christie 1336aed10b [SCSI] libiscsi: check if iscsi host has work queue before queueing work
Instead of having libiscsi check if the offload bit is set, have
it check if the lld created a work queue. I think this is more
clear.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:12 -05:00
Mike Christie 301e0f7e4d [SCSI] libiscsi: don't let io sit in queue when session has failed
If the session is failed, but we have not yet fully transitioned
to the recovery stage we were still queueuing IO. The idea is
that for some failures we can recvover at the command level
and still continue to execute other IO. Well, we never have
added the recovery within a command code, so queueing up IO here
just creates the possibility that it might time time out so
this just has us requeue the IO the scsi layer for now.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:12 -05:00
Mike Christie 3bbaaad95f [SCSI] libiscsi: handle cleanup task races
bnx2i needs to send a hardware specific cleanup command if
a command has not completed normally (iscsi/scsi response from
target), and the session is still ok (this is the case when we
send a TMF to stop the command).

At this time it will need to drop the session lock. The problem
with the current code is that fail_all_commands assumes we
will hold the lock the entire time, so it uses list_for_each_entry_safe.
If while bnx2i drops the session lock multiple cmds complete then
list_for_each_entry_safe will not handle this correctly.

This patch removes the running lists and just has us loop over
the cmds array (in later patches we will then replace that
array with a block tag map at the session level). It also fixes
up the completion path so that if the TMF code and the normal recv
path were completing the same command then they both do not try
to do release the refcount taken when the task is queued.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:12 -05:00
Mike Christie 4c48a82935 [SCSI] libiscsi: fix iscsi transport checks to account for slower links
If we have not got any pdus for recv_timeout seconds, then we will
send a iscsi ping/nop to make sure the target is still around. The
problem is if this is a slow link, and the ping got queued after
the data for a data_out (read), then the transport code could think
the ping has failed when it is just slowly making its way through
the network. This patch has us check if we are making progress while
the nop is outstanding. If we are still reading in data, then we
do not fail the session at that time.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:11 -05:00
Mike Christie 26013ad4c4 [SCSI] libiscsi: fix nop response/reply and session cleanup race
If we are responding to a nop from the target by sending our nop,
and the session is getting torn down, then iscsi_start_session_recovery
could set the conn stop bits while the recv path is sending the nop
response and we will hit the bug ons in __iscsi_conn_send_pdu.

This has us check the state in __iscsi_conn_send_pdu and fail all
incoming mgmt IO if we are  not logged in and if the pdu is not login
related. It also changes the ordering of the setting of conn stop state
bits so they are set after the session state is set (both are set under
the session lock).

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:11 -05:00
Mike Christie edbc9aa058 [SCSI] libiscsi: have iscsi_data_in_rsp call iscsi_update_cmdsn
This has iscsi_data_in_rsp call iscsi_update_cmdsn when a pdu is
completed like is done for other pdu's that are don.

For libiscsi_tcp, this means that it calls iscsi_update_cmdsn when
it is handling the pdu internally to only transfer data, but if there is
status then it does not need to call it since the completion handling
will do it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:10 -05:00
Mike Christie 8f9256cea1 [SCSI] libiscsi: export iscsi_itt_to_task for bnx2i
bnx2i needs to be able to look up mgmt task like login and nop, because
it does some processing of them on the completion path. This exports
iscsi_itt_to_task so it can look up the task.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:10 -05:00
Mike Christie 5700b1af93 [SCSI] libiscsi: handle param allocation failures
If we could not allocate the initiator name or some other id like
the hwaddress or netdev, then userspace could deal with the failure
by just running in a dregraded mode.

Now we want to be able to switch values for the params and we
want some feedback, so this patch will check if a string like
the initiatorname could not be allocated and return an error.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:10 -05:00
Mike Christie 184b57c630 [SCSI] libiscsi: check of LLD has a alloc pdu callout.
bnx2i does not have one. It currently preallocates the bdt
when the session is setup.

We probably want to change that to a dma pool, then allocate from
the pool in the alloc pdu. Until then check if there is a alloc
pdu callout.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:09 -05:00
Mike Christie 6b5d6c443a [SCSI] cxgb3i, iser, iscsi_tcp: set target can queue
Set target can queue limit to the number of preallocated
session tasks we have.

This along with the cxgb3i can_queue patch will fix a throughput
problem where it could only queue one LU worth of data at a time.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 10:09:54 -05:00
Jean Delvare fd6e1c14b7 [SCSI] libiscsi: fix iscsi pool error path
Le lundi 30 mars 2009, Chris Wright a écrit :
> q->queue could be ERR_PTR(-ENOMEM) which will break unwinding
> on error.  Make iscsi_pool_free more defensive.
>

Making the freeing of q->queue dependent on q->pool being set looks
really weird (although it is correct at the moment. But this seems
to be fixable in a much simpler way.

With the benefit that only the error case is slowed down. In both
cases we have a problem if q->queue contains an error value but it's
not -ENOMEM. Apparently this can't happen today, but it doesn't feel
right to assume this will always be true. Maybe it's the right time
to fix this as well.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-03 09:23:14 -05:00
Mike Christie 728996829b [SCSI] libiscsi: fix possbile null ptr session command cleanup
If the iscsi eh fires when the current task is a nop, then
the task->sc pointer is null. fail_all_commands could
then try to do task->sc->device and oops. We actually do
not need to access the curr task in this path, because
if it is a cmd task the fail_command call will handle
this and if it is mgmt task then the flush of the mgmt
queues will handle that.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:29:54 -05:00
Mike Christie 40a06e755d [SCSI] libiscsi: pass session failure a session struct
The api for conn and session failures is akward because
one takes a conn from the lib and one takes a session
from the class. This syncs up the interfaces to use
structs from the lib.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:29:12 -05:00
Mike Christie 4d1083509a [SCSI] iscsi lib: remove qdepth param from iscsi host allocation
The qdepth setting was useful when we needed libiscsi to verify
the setting. Now we just need to make sure if older tools
passed in zero then we need to set some default.

So this patch just has us use the sht->cmd_per_lun or if
for LLD does a host per session then we can set it on per
host basis.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:28:55 -05:00
Mike Christie 32ae763e3f [SCSI] iscsi lib: have lib create work queue for transmitting IO
We were using the shost work queue which ended up being
a little akward since all iscsi hosts need a thread for
scanning, but only drivers hooked into libiscsi need
a workqueue for transmitting. So this patch moves the
xmit workqueue to the lib.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:28:37 -05:00
Mike Christie e28f3d5b51 [SCSI] libiscsi: don't cap queue depth in iscsi modules
There is no need to cap the queue depth in the modules. We set
this in userspace and can do that there. For performance testing
with ram based targets, this is helpful since we can have very
high queue depths.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:28:06 -05:00
Mike Christie 1b2c7af877 [SCSI] libiscsi: replace scsi_debug logging with session/conn logging
This makes the logging a compile time option and replaces
the scsi_debug macro with session and connection ones
that print out a driver model id prefix.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:27:09 -05:00
Jean Delvare f474a37bc4 [SCSI] libiscsi: fix iscsi pool error path
Memory freeing in iscsi_pool_free() looks wrong to me. Either q->pool
can be NULL and this should be tested before dereferencing it, or it
can't be NULL and it shouldn't be tested at all. As far as I can see,
the only case where q->pool is NULL is on early error in
iscsi_pool_init(). One possible way to fix the bug is thus to not
call iscsi_pool_free() in this case (nothing needs to be freed anyway)
and then we can get rid of the q->pool check.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:25:53 -05:00
Mike Christie 308cec14e6 [SCSI] libiscsi: Fix scsi command timeout oops in iscsi_eh_timed_out
Yanling Qi from LSI found the root cause of the panic, below is his
analysis:

Problem description: the open iscsi driver installs eh_timed_out handler
to the
blank_transport_template of the scsi middle level that causes panic of
timed
out command of other host

Here are the details

Iscsi Session creation

During iscsi session creation time, the iscsi_tcp_session_create() of
iscsi_tpc.c will create a scsi-host for the session. See the statement
marked
with the label A. The statement B replaces the shost->transportt point
with a
local struct variable.

static struct iscsi_cls_session *
iscsi_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
                         uint16_t qdepth, uint32_t initial_cmdsn,
                         uint32_t *hostno)
{
        struct iscsi_cls_session *cls_session;
        struct iscsi_session *session;
        struct Scsi_Host *shost;
        int cmd_i;
        if (ep) {
                printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
                return NULL;
        }

A        shost = iscsi_host_alloc(&iscsi_sht, 0, qdepth);

        if (!shost)

                return NULL;

B         shost->transportt = iscsi_tcp_scsi_transport;

        shost->max_lun = iscsi_max_lun;

Please note the scsi host is allocated by invoking isccsi_host_alloc()
in
libiscsi.c

Polluting the middle level blank_transport_template in
iscsi_host_alloc() of
libiscsi.c

The iscsi_host_alloc() invokes the middle level function
scsi_host_alloc() in
hosts.c for allocating a scsi_host. Then the statement marked with C
assigns
the iscsi_eh_cmd_timed_out handler to the eh_timed_out callback
function.

struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,

                                   int dd_data_size, uint16_t qdepth)

{
        struct Scsi_Host *shost;
        struct iscsi_host *ihost;
        shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) +
dd_data_size);
        if (!shost)
                return NULL;

 C      shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;

Please note the shost->transport is the middle level
blank_transport_template
as shown in the code segment below. We see two problems here. 1.
iscsi_eh_cmd_timed_out is installed to the blank_transport_template that
will
cause some body else problem. 2. iscsi_eh_cmd_timed_out will never be
invoked
when iscsi command gets timeout because the statement B resets the
pointer.

Middle level blank_transport_template

In the middle level function scsi_host_alloc() of hosts.c, the middle
level
assigns a blank_transport_template for those hosts not implementing its
transport layer. All HBAs without supporting a specific scsi_transport
will
share the middle level blank_transport_template. Please see the
statement D

struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int
privsize)

{
        struct Scsi_Host *shost;
        gfp_t gfp_mask = GFP_KERNEL;
        int rval;
        if (sht->unchecked_isa_dma && privsize)
                gfp_mask |= __GFP_DMA;

         shost = kzalloc(sizeof(struct Scsi_Host) + privsize, gfp_mask);
        if (!shost)
                return NULL;

        shost->host_lock = &shost->default_lock;

        spin_lock_init(shost->host_lock);

        shost->shost_state = SHOST_CREATED;

        INIT_LIST_HEAD(&shost->__devices);

        INIT_LIST_HEAD(&shost->__targets);

        INIT_LIST_HEAD(&shost->eh_cmd_q);

        INIT_LIST_HEAD(&shost->starved_list);

        init_waitqueue_head(&shost->host_wait);

        mutex_init(&shost->scan_mutex);

        shost->host_no = scsi_host_next_hn++; /* XXX(hch): still racy */

        shost->dma_channel = 0xff;

        /* These three are default values which can be overridden */

        shost->max_channel = 0;

        shost->max_id = 8;

        shost->max_lun = 8;

        /* Give each shost a default transportt */

 D       shost->transportt = &blank_transport_template;

Why we see panic at iscsi_eh_cmd_timed_out()

The mpp virtual HBA doesn’t have a specific scsi_transport. Therefore,
the
blank_transport_template will be assigned to the virtual host of the MPP
virtual HBA by SCSI middle level. Please note that the statement C has
assigned
iscsi-transport eh_timedout handler to the blank_transport_template.
When a mpp
virtual command gets timedout, the iscsi_eh_cmd_timed_out() will be
invoked to
handle mpp virtual command timeout from the middle level
scsi_times_out()
function of the scsi_error.c.

enum blk_eh_timer_return scsi_times_out(struct request *req)

{

        struct scsi_cmnd *scmd = req->special;

        enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);

        enum blk_eh_timer_return rtn = BLK_EH_NOT_HANDLED;

        scsi_log_completion(scmd, TIMEOUT_ERROR);

        if (scmd->device->host->transportt->eh_timed_out)

 E               eh_timed_out =
scmd->device->host->transportt->eh_timed_out;

        else if (scmd->device->host->hostt->eh_timed_out)

                eh_timed_out = scmd->device->host->hostt->eh_timed_out;

        else

                eh_timed_out = NULL;

        if (eh_timed_out) {

                rtn = eh_timed_out(scmd);

It is very easy to understand why we get panic in the
iscsi_eh_cmd_timed_out().
A scsi_cmnd from a no-iscsi device definitely can not resolve out a
session and
session->lock. The panic can be happed anywhere during the differencing.

static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd
*scmd)

{

        struct iscsi_cls_session *cls_session;

        struct iscsi_session *session;

        struct iscsi_conn *conn;

        enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;

        cls_session = starget_to_session(scsi_target(scmd->device));

        session = cls_session->dd_data;

        debug_scsi("scsi cmd %p timedout\n", scmd);

        spin_lock(&session->lock);

This patch fixes the problem by moving the setting of the
iscsi_eh_cmd_timed_out to iscsi_add_host, which is after the LLDs
have set their transport template to shost->transportt.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-02-10 11:15:19 -05:00
Mike Christie 2f5899a39d [SCSI] libiscsi: fix iscsi pool leak
I am not sure what happened. It looks like we have always leaked
the q->queue that is allocated from the kfifo_init call. nab finally
noticed that we were leaking and this patch fixes it by adding a
kfree call to iscsi_pool_free. kfifo_free is not used per kfifo_init's
instructions to use kfree.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-01-25 07:54:37 -06:00
Mike Christie ae15f80172 [SCSI] libiscsi: handle init task failures.
Mgmt setup used to not fail so we did not have to check
the return value. Now with cxgb3i it can so this has us
pass up a error.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:23 -06:00
Mike Christie 2ff79d52d5 [SCSI] libiscsi: pass opcode into alloc_pdu callout
We do not need to allocate a itt for data_out, so this
passes the opcode to the alloc_pdu callout.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:23 -06:00
Mike Christie 262ef63627 [SCSI] libiscsi: allow drivers to modify the itt sent to the target
bnx2i and cxgb3i need to encode LLD info in the itt so that
the firmware/hardware can process the pdu. This patch allows
the LLDs to encode info in the task->hdr->itt that they
setup in the alloc_pdu callout (any resources that are allocated
can be freed with the pdu in the cleanup_task callout). If
the LLD encodes info in the itt they should implement a
parse_pdu_itt callout. If parse_pdu_itt is not implemented
libiscsi will do the right thing for the LLD.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:22 -06:00
Mike Christie cfeb2cf957 [SCSI] libiscsi: change login data buffer allocation
This modifies the login buffer allocation to use __get_free_pages.
It will allow drivers that want to send this data with zero copy
operations to easily line things up on page boundaries.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:21 -06:00
Mike Christie 577577da6d [SCSI] libiscsi: prepare libiscsi for new offload engines by modifying unsol data code
cxgb3i offloads data transfers. It does not offload the entire scsi/iscsi
procssing like qla4xxx and it does not offload the iscsi sequence
processing like how bnx2i does. cxgb3i relies on iscsi_tcp for the
seqeunce handling so this changes how we transfer unsolicitied data by
adding a common r2t struct and helpers.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:20 -06:00
Mike Christie d3acf0226d [SCSI] libiscsi REGRESSION: fix passthrough support with older iscsi tools
This regression was added in 2.6.27, when the mtask and ctask were
merged into the the common task struct. The patch applies to
scsi-rc-fixes, but also applies to 2.6.27 with some offsets.

The problem is that __iscsi_conn_send_pdu assumes that userspace was
not sending nops with the format it is checking for in the "if" below.
It turns out that older userspace tools are. This patch moves the
setting of the internal ping_task tracker (it tracks libiscsi current
outstanding nop) to iscsi_send_nopout which is only used by kernel callers.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-03 10:09:19 -06:00
Mike Christie a343914831 libiscsi: fix locking in iscsi_eh_device_reset
We must be using the bh spin locking functions in
iscsi_eh_device_reset becuase the session lock interacts with
a thread and softirq.

This patch also fixes up a bogus comment and check in fail_command,
because no one drops the lock (bnx2i did but it is not going
upstream yet and there were other refcount changes for that).

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:29:01 -04:00
Mike Christie 87cd9eab2d libiscsi: check reason why we are stopping iscsi session to determine error value
Some wires got crossed on some patches and I messed up in the code
below when rebuilding a patch. We want to be checking if flag
equaled the value indicating if we killing the session due to
final logout or if we just trying to relogin.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:29:01 -04:00
Mike Christie 8e12452549 [SCSI] libiscsi: rename host reset to target reset
I had this in my patchset to add target reset support, but
it got dropped due to patching conflicts. This initial patch
just renames the function and users. We are actually just
dropping the session, and so this does not have anything to do
with the host exactly. It does for software iscsi because
we allocate a host per session, but for cxgb3i this makes no
sense.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:59 -04:00
Mike Christie e5bd7b54e9 [SCSI] libiscsi: Support drivers initiating session removal
If the driver knows when hardware is removed like with cxgb3i,
bnx2i, qla4xxx and iser then we will want to remove the sessions/devices
that are bound to that device before removing the host.

cxgb3i and in the future bnx2i will remove the host and that will
remove all the sessions on the hba. iser can call iscsi_kill_session
when it gets an event that indicates that a hca is removed.
And when qla4xxx is hooked in to the lib (it is only hooked into
the class right now) it can call iscsi remove host like the
partial offload card drivers.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:59 -04:00
Mike Christie 1d9edf0270 [SCSI] libiscsi: fix data corruption when target has to resend data-in packets
iscsi_tcp was updating the exp_statsn (exp_statsn acknowledges
status and tells the target it is ok to let the resources for
a iscsi pdu to be reused) before it got all the data for pdu read
into OS buffers. Data corruption was occuring if something happens
to a packet and the network layer requests a retransmit, and the
initiator has told the target about the udpated exp_statsn ack,
then the target may be sending data from a buffer it has reused
for a new iscsi pdu. This fixes the problem by having the LLD
(iscsi_tcp in this case) just handle the transferring of data, and
has libiscsi handle the processing of status (libiscsi completion
processing is done after LLD data transfers are complete).

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:58 -04:00
Mike Christie 56d7fcfa81 [SCSI] iscsi class, libiscsi and qla4xxx: convert to new transport host byte values
This patch converts the iscsi drivers to the new host byte values.

v2
Drop some conversions. Want to avoid conflicts with other patches.
v1
initial patch.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:49 -04:00
Mike Christie d6d13ee19d [SCSI] libiscsi: Use SCSI_MLQUEUE_TARGET_BUSY
For the conditions below we do not want the queuecommand
function to call us right back, so return SCSI_MLQUEUE_TARGET_BUSY.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:47 -04:00
Linus Torvalds ef5bef357c Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (37 commits)
  [SCSI] zfcp: fix double dbf id usage
  [SCSI] zfcp: wait on SCSI work to be finished before proceeding with init dev
  [SCSI] zfcp: fix erp list usage without using locks
  [SCSI] zfcp: prevent fc_remote_port_delete calls for unregistered rport
  [SCSI] zfcp: fix deadlock caused by shared work queue tasks
  [SCSI] zfcp: put threshold data in hba trace
  [SCSI] zfcp: Simplify zfcp data structures
  [SCSI] zfcp: Simplify get_adapter_by_busid
  [SCSI] zfcp: remove all typedefs and replace them with standards
  [SCSI] zfcp: attach and release SAN nameserver port on demand
  [SCSI] zfcp: remove unused references, declarations and flags
  [SCSI] zfcp: Update message with input from review
  [SCSI] zfcp: add queue_full sysfs attribute
  [SCSI] scsi_dh: suppress comparison warning
  [SCSI] scsi_dh: add Dell product information into rdac device handler
  [SCSI] qla2xxx: remove the unused SCSI_QLOGIC_FC_FIRMWARE option
  [SCSI] qla2xxx: fix printk format warnings
  [SCSI] qla2xxx: Update version number to 8.02.01-k8.
  [SCSI] qla2xxx: Ignore payload reserved-bits during RSCN processing.
  [SCSI] qla2xxx: Additional residual-count corrections during UNDERRUN handling.
  ...
2008-10-10 10:53:26 -07:00
Jens Axboe 242f9dcb8b block: unify request timeout handling
Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
Mike Christie ac26d41dee [SCSI] libiscsi: return error passed in during iscsi recovery
Due to patch building error on my side, we are still passing DID_BUS_BUSY
for commands that are running, when we want to return whatever the caller
of fail_all_commands wanted. This replaces the hardcoded error code with
the value that is passed in.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-03 11:46:16 -05:00
Mike Christie 8e9a20cee4 [SCSI] libiscsi, iscsi_tcp, ib_iser: fix setting of can_queue with old tools.
This patch fixes two bugs that are related.

1. Old tools did not set can_queue/cmds_max. This patch modifies
libiscsi so that when we add the host we catch this and set it
to the default.

2. iscsi_tcp thought that the scsi command that was passed to
the eh functions needed a iscsi_cmd_task allocated for it. It
only needed a mgmt task, and now it does not matter since it
all comes from the same pool and libiscsi handles this for the
drivers. ib_iser had copied iscsi_tcp's code and set can_queue
to its max - 1 to handle this. So this patch removes the max -1,
and just sets it to the max.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:29 -05:00
Harvey Harrison 8f333991ba [SCSI] scsi: use get_unaligned_* helpers
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:23 -05:00
Mike Christie 913e5bf435 [SCSI] libiscsi, iser, tcp: remove recv_lock
The recv lock was defined so the iscsi layer could block
the recv path from processing IO during recovery. It
turns out iser just set a lock to that pointer which was pointless.

We now disconnect the transport connection before doing recovery
so we do not need the recv lock. For iscsi_tcp we still stop
the recv path incase older tools are being used.

This patch also has iscsi_itt_to_ctask user grab the session lock
and has the caller access the task with the lock or get a ref
to it in case the target is broken and sends a tmf success response
then sends data or a response for the command that was supposed to
be affected bty the tmf.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:22 -05:00
Mike Christie 3cf7b233ff [SCSI] libiscsi: fix cmds_max setting
Drivers expect that the cmds_max value they pass to the iscsi layer
is the max scsi commands  + mgmt tasks. This patch implements that
and fixes some checks for nr cmd limits.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:21 -05:00
Mike Christie 88dfd340b9 [SCSI] iscsi class: Add session initiatorname and ifacename sysfs attrs.
This adds two new attrs used for creating initiator ports and
binding sessions to hardware.

The session level initiatorname:

Since bnx2i does a scsi_host per host device, we need to add the
iface initiator port settings on the session, so we can create
multiple initiator ports (each with different inames) per device/scsi_host.

The current iname reflects that qla4xxx can have one iname per hba, and we are
allocating a host per session for software. The iname on the host will
remain so we can export and set the hba level qla4xxx setting.

The ifacename attr:

To bind a session to a some peice of hardware in userspace we maintain
some mappings, but during boot or iscsid restart (iscsid contains the user
space part of the driver) we need to be able to figure out which of those
host mappings abstractions maps to certain sessions. This patch adds
a ifacename attr, which userspace can set to id the host side of the
endpoint across pivot_roots and iscsid restarts.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:21 -05:00
Mike Christie 7970634b81 [SCSI] iscsi class: user device_for_each_child instead of duplicating session list
Currently we duplicate the list of sessions, because we were using the
test for if a session was on the host list to indicate if the session
was bound or unbound. We can instead use the target_id and fix up
the class so that drivers like bnx2i do not have to manage the target id
space.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:20 -05:00
Mike Christie 9c19a7d038 [SCSI] libiscsi: rename iscsi_cmd_task to iscsi_task
This is the second part of the iscsi task merging, and
all it does it rename iscsi_cmd_task to iscsi_task and
mtask/ctask to just task.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:19 -05:00
Mike Christie 3e5c28ad03 [SCSI] libiscsi: merge iscsi_mgmt_task and iscsi_cmd_task
There is no need to have the mgmt and cmd tasks separate
structs. It used to save a lot of memory when we overprealocated
memory for tasks, but the next patches will set up the
driver so in the future they can use a mempool or some other
common scsi command allocator and common tagging.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:19 -05:00
Mike Christie 052d014485 [SCSI] libiscsi: modify libiscsi so it supports offloaded data paths
This patch modifies libiscsi, so drivers like bnx2i and iser can execute
a command from queuecommand/send_pdu instead of having to be queued to
be run in a workq.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:18 -05:00
Mike Christie 0af967f5d4 [SCSI] libiscsi, iscsi_tcp, iser: add session cmds array accessor
Currently to get a ctask from the session cmd array, you have to
know to use the itt modifier. To make this easier on LLDs and
so in the future we can easilly kill the session array and use
the host shared map instead, this patch adds a nice wrapper
to strip the itt into a session->cmds index and return a ctask.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:18 -05:00
Mike Christie b40977d95f [SCSI] iser: fix handling of scsi cmnds during recovery.
After the stop_conn callback has returned the LLD should not
touch the scsi cmds. iscsi_tcp and libiscsi use the
conn->recv_lock and suspend_rx field to halt recv path
processing, but iser does not have any protection.

This patch modifies iser so that userspace can just
call the ep_disconnect callback, which will halt
all recv IO, before calling the stop_conn callback so
we do not have to worry about the conn->recv_lock and
suspend rx field. iser just needs to stop the send side
from accessing the ib conn.

Fixup to handle when the ep poll fails and ep disconnect
is called from Erez.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:17 -05:00
Mike Christie 5d91e209fb [SCSI] iscsi: remove session/conn_data_size from iscsi_transport
This removes the session and conn data_size fields from the iscsi_transport.
Just pass in the value like with host allocation. This patch also makes
it so the LLD iscsi_conn data is allocated with the iscsi_cls_conn.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:16 -05:00