Commit Graph

198 Commits

Author SHA1 Message Date
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
Mike Christie a4804cd6eb [SCSI] iscsi: add iscsi host helpers
This finishes the host/session unbinding, by adding some helpers
to add and remove hosts and the session they manage.

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
Mike Christie 756135215e [SCSI] iscsi: remove session and host binding in libiscsi
bnx2i allocates a host per netdevice but will use libiscsi,
so this unbinds the session from the host in that code.

This will also be useful for the iser parent device dma settings
fixes.

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
Mike Christie d3826721b1 [SCSI] iscsi class, iscsi drivers: remove unused iscsi_transport attrs
max_cmd_len and max_conn are not really used. max_cmd_len is
always 16 and can be set by the LLD. max_conn is always one
since we do not support MCS.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:15 -05:00
Mike Christie c8611f9754 [SCSI] libiscsi regression in 2.6.25: fix setting of recv timer
If the ping tmo is longer than the recv tmo then we could miss a window
where we were supposed to check the recv tmo. This happens because
the ping code will set the next timeout for the ping timeout, and if the
ping executes quickly there will be a long chunk of time before the
timer wakes up again.

This patch has the ping processing code kick off a recv
tmo check when getting a nop in response to our ping.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-05-08 20:38:57 -05:00
Mike Christie 4cf1043593 [SCSI] libiscsi regression in 2.6.25: fix nop timer handling
The following patch fixes a bug in the iscsi nop processing.
The target sends iscsi nops to ping the initiator and the
initiator has to send nops to reply and can send nops to
ping the target.

In 2.6.25 we moved the nop processing to the kernel to handle
problems when the userspace daemon is not up, but the target
is pinging us, and to handle when scsi commands timeout, but
the transport may be the cause (we can send a nop to check
the transport). When we added this code we added a bug where
if the transport timer wakes at the exact same time we are supposed to check
for a nop timeout we drop the session instead of checking the transport.

This patch checks if a iscsi ping is outstanding and if the ping has
timed out, to determine if we need to signal a connection problem.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-05-08 10:04:54 -05:00
Boaz Harrosh c07d444407 [SCSI] iscsi: bidi support at the generic libiscsi level
- prepare the additional bidi_read rlength header.
- access the right scsi_in() and/or scsi_out() side of things.
  also for resid.
- Handle BIDI underflow overflow from target

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Reviewed-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-18 11:53:00 -05:00
Boaz Harrosh 38d1c069db [SCSI] iscsi: extended cdb support
Support for extended CDBs in iscsi.
All we need is to check if command spills over 16 bytes then allocate
an iscsi-extended-header for the leftovers.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Reviewed-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-18 11:51:19 -05:00
Mike Christie 31ed0bf439 [SCSI] iscsi regression: check for zero max session cmds
The old tools did not set max session cmds. This is a regression.
I removed the check when merging the power of 2 patch.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-27 15:52:46 -08:00
Mike Christie 8b1d03434e [SCSI] libiscsi: fix session age rollover and remove cid encoding
The session age mask is only 4 bits, but session->age is 32. When
it gets larger then 15 and we try to or the bits some bits get
dropped and the check for session age in iscsi_verify_itt is useless.

The ISCSI_CID_MASK related bits are also useless since cid is always
one.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-07 18:02:37 -06:00
Mike Christie 322d739da8 [SCSI] iscsi: fix up iscsi printk prefix
Some iscsi class messages have the dev_printk prefix and some libiscsi
and iscsi_tcp messages have "iscsi" or the module name as a prefix which
is normally pretty useless when trying to figure out which session
or connection the message is attached to. This patch adds iscsi lib
and class dev_printks so all messages have a common prefix that
can be used to figure out which object printed it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-07 18:02:37 -06:00
Mike Christie ad294e9cd1 [SCSI] libiscsi: fix setting of nop timer
If we rollover then we could get a next_timeout of zero, so we need
to set the new timer to that value.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-07 18:02:37 -06:00
Mike Christie 6eabafbe66 [SCSI] iscsi class, libiscsi: add iscsi sysfs session state file
This adds a iscsi session state file which exports the session
state for both software and hardware iscsi. It also hooks libiscsi
in.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-07 18:02:34 -06:00
Adrian Bunk f8d9d654fc [SCSI] libiscsi: make __iscsi_complete_pdu() static
__iscsi_complete_pdu() can now become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-07 18:02:33 -06:00
vignesh babu 1183657217 [SCSI] libiscsi: use is_power_of_2
Replacing n & (n - 1) for power of 2 check by is_power_of_2(n)

Signed-off-by: vignesh babu <vignesh.babu@wipro.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:51 -06:00
Mike Christie 4cd49ea133 [SCSI] libiscsi, iscsi class: set tmf to a safe default and export in sysfs
Older tools will not be setting the tmf time outs since they
did not exists, so set them to a safe default.

And export abort and lu reset timeout values in sysfs.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:46 -06:00
Olaf Kirch a8ac6311cc [SCSI] iscsi: convert xmit path to iscsi chunks
Convert xmit to iscsi chunks.

from michaelc@cs.wisc.edu:

Bug fixes, more digest integration, sg chaining conversion and other
sg wrapper changes, coding style sync up, and removal of io fields,
like pdu_sent, that are not needed.

Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:42 -06:00
Mike Christie 1040c99d9f [SCSI] libiscsi: Drop host lock in queuecommand
The driver does not need the host lock in queuecommand so drop it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:41 -06:00
Mike Christie c1635cb786 [SCSI] libiscsi: clear conn->ctask when task is completed early
If the current ctask is failed early, we legt the conn->ctask pointer
pointing to a invalid task. When the xmit thread would send data for
it, we would then oops.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:39 -06:00
Mike Christie 9000bcd649 [SCSI] libiscsi: Do not fail commands immediately during logout
If the target requests a logout, then we do not want
to fail commands to scsi-ml right away. This patch just
fails in pending commands for a requeue immediately, and then lets
iscsid handle running commands like normal recovery.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:38 -06:00
Mike Christie f6d5180c78 [SCSI] libiscsi: fix nop handling
During root boot and shutdown the target could send us nops.
At this time iscsid cannot be running, so the target will drop
the session and the boot or shutdown will hang.

To handle this and allow us to better control when to check the network
this patch moves the nop handling to the kernel.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:35 -06:00
Mike Christie 2697478903 [SCSI] libiscsi: fix shutdown
We were using the device delete sysfs file to remove each device
then logout. Now in 2.6.21 this will not work because
the sysfs delete file returns immediately and does not wait for
the device removal to complete. This causes a hang if a cache sync
is needed during shutdown. Before .21, that approach had other
problems, so this patch fixes the shutdown code so that we remove the target
and unbind the session before logging out and shut down the session

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:33 -06:00
Mike Christie bc436b2787 [SCSI] libiscsi: grab eh_mutex during host reset
I thought we may not need the eh mutex during host reset, but that is wrong
with the new shutdown code. When start_session_recovery sets the state to
terminate then drops the session lock. The scsi eh thread could then grab the
session lock see that we are terminating and then return failed to scsi-ml.
scsi-ml's eh then owns the command and will do whatever it wants
with it. But then the iscsi eh thread could grab the session lock
and want to complete the scsi commands that we in the LLD, but
it no longer owns them and kaboom.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:31 -06:00
Mike Christie b3a7ea8d50 [SCSI] libiscsi: do not block session during logout
There is not need to block the session during logout. Since
we are going to fail the commands that were blocked just fail them
immediately instead.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:28 -06:00
Olaf Kirch 6320377fd9 [SCSI] libiscsi, iscsi_tcp: iscsi pool cleanup
iscsi_pool_init simplified

iscsi_pool_init currently has a lot of duplicate kfree() calls it does
when some allocation fails. This patch simplifies the code a little by
using iscsi_pool_free to tear down the pool in case of an error.

iscsi_pool_init also returns a copy of the item array to the caller.
Not all callers use this array, so we make it optional.

Instead of allocating a second array and return that, allocate just one
array, of twice the size.

Update users of iscsi_pool_{init,free}

This patch drops the (now useless) second argument to
iscsi_pool_free, and updates all callers.

It also removes the ctask->r2ts array, which was never
used anyway. Since the items argument to iscsi_pool_init
is now optional, we can pass NULL instead.

Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:27 -06:00
Boaz Harrosh 38ad03de3f [SCSI] libiscsi,iser: patch for AHS support
- The default initialization of hdr_max is the minimum -
    sizeof(struct iscsi_cmd) - Once this patch goes into iser the default
    initialization at libiscsi can be removed.
  - This is not yet full support for AHSs at iser end. But it should be easy.
    Just allocate more space at iser_desc right after iscsi_hdr. Than
    at transmission time use ctask->hdr_len to retrieve the total
    size of all iscsi pdu headers. See previous patch at iscsi_tcp.[ch]

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:25 -06:00
Boaz Harrosh 004d6530f8 [SCSI] iscsi_tcp, libiscsi: initial AHS Support
at libiscsi generic code
  - currently code assumes a storage space of pdu header is allocated
    at llds ctask and is pointed to by iscsi_cmd_task->hdr. Here I add
    a hdr_max field pertaining to that storage, and an hdr_len that
    accumulates the current use of the pdu-header.

  - Add an iscsi_next_hdr() inline which returns the next free space
    to write new Header at. Also iscsi_next_hdr() is used to retrieve
    the address at which to write the header-digest.

  - Add iscsi_add_hdr(length). What the user do is calls iscsi_next_hdr()
    for address of the new header, than calls iscsi_add_hdr(length) with
    the size of the new header. iscsi_add_hdr() will check if space is
    available and update to the new size. length must be padded according
    to standard.

  - Add 2 padding inline helpers thanks to Olaf. Current patch does not
    use them but Following patches will.
    Also moved definition of ISCSI_PAD_LEN to iscsi_proto.h which had
    PAD_WORD_LEN that was never used anywhere.

  - Let iscsi_prep_scsi_cmd_pdu() signal an Error return since now  it is
    possible that it will fail.

  - I was tired of yet again writing a "this is a digest" comment next to
    sizeof(__u32) so I defined a new ISCSI_DIGEST_SIZE. Now I don't need
    any comments. Changed all places that used sizeof(__u32) or "4" in
    connection to a digest.

  iscsi_tcp specific code
  - At struct iscsi_tcp_cmd_task allocate maximum space allowed in
    standard for all headers following the iscsi_cmd header. and mark
    it so in iscsi_tcp_session_create()
  - At iscsi_send_cmd_hdr() retrieve the correct headers size and
    write header digest at iscsi_next_hdr().

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:23 -06:00
Boaz Harrosh 7207fea452 [SCSI] iscsi: Prettify resid handling and some extra checks
- Check to see that OVERFLOW is not negative indicating
    a bug.
  - Unify handling of UNDERFLOW and OVERFLOW to the same
    code.
  - Also handle BIDI_OVERFLOW.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:22 -06:00
Mike Christie 843c0a8a76 [SCSI] libiscsi, iscsi_tcp: add device support
This patch adds logical unit reset support. This should work for ib_iser,
but I have not finished testing that driver so it is not hooked in yet.

This patch also temporarily reverts the iscsi_tcp r2t write out patch.
That code is completely rewritten in this patchset.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:19 -06:00
Tony Battersby 6ee6a2f025 [SCSI] iscsi: return data transfer residual for data-out commands
Currently, the iSCSI driver returns the data transfer residual for
data-in commands (e.g. read) but not data-out commands (e.g. write).
This patch makes it return the data transfer residual for both types of
commands.

Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2007-11-14 14:52:16 -06:00
Mike Christie 6724add1b5 [SCSI] libiscsi: sync up iscsi and scsi eh's access to the connection
The iscsi eh could be tearing down the session/connection while
the scsi eh is still sending task management functions. If when
we drop the session lock to grab the recv lock, the iscsi eh
tears down the connection we will oops.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-08-15 13:09:21 -05:00
Mike Christie 96809f1b15 [SCSI] libiscsi: fix null ptr regression when aborting a command with data to transfer
We do not want to send data if we are aborting a task. There is
a check in iscsi_xmit_ctask, but right before calling this we overwrite
the state so we always go right past the test. Sending data causes problems
because when we clean up from a successful abort the LLD assumes that
the task is not running.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-08-15 13:08:14 -05:00
Mike Christie e07264071f [SCSI] libiscsi: fix cmd seqeunce number checking
We should not be checking the cmd windown for just handling r2t responses.
And if the window closes in on us, always have scsi-ml requeue the command
from our queuecommand function.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-07-27 09:12:05 -04:00
Mike Christie 464bb99ea4 [SCSI] libiscsi: make sure session is not blocked when removing host
When we logout we block the session since we are not taking any more
commands, but when we call remove host we want to make sure any
IO that got queued up and blocked gets failed upwards quickly, so
we unblock the session and fail it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-07-27 09:11:14 -04:00
FUJITA Tomonori 1c13899154 [SCSI] iscsi_tcp: convert to use the data buffer accessors
- remove the unnecessary map_single path.

- convert to use the new accessors for the sg lists and the
parameters.

TODO: use scsi_for_each_sg().

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-06-17 16:01:55 -05:00