Commit Graph

140 Commits

Author SHA1 Message Date
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