We can only have one task management comment outstanding, so move the
completion and status to the target port. This allows us to handle
resets of a LUN without a corresponding request having been sent.
Meanwhile, we don't need to play games with host_scribble, just use it
as the pointer it is.

This fixes a crash when we issue a bus reset using sg_reset.

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=13893Reported-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NDavid Dillow <dillowda@ornl.gov>

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: NJeff Garzik <jgarzik@redhat.com>
Acked-by: NJames Bottomley <James.Bottomley@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use the new {max,min}3 macros to save some cycles and bytes on the stack.
This patch substitutes trivial nested macros with their counterpart.
Signed-off-by: NHagen Paul Pfeifer <hagen@jauu.net>
Cc: Joe Perches <joe@perches.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

srp_send_tsk_mgmt() was missing the proper DMA sync calls before posting
the buffer to the device.
Signed-off-by: NDavid Dillow <dillowda@ornl.gov>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Use the list_first_entry() macro in ib_srp instead of open-coding the equivalent,
which makes the source code slightly more descriptive.  The list_first_entry()
macro itself was introduced in kernel 2.6.22.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NDavid Dillow <dillowda@ornl.gov>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

As proposed by the SRP (draft) standard, ib_srp reserves one ring
element for SRP_TSK_MGMT requests. This patch makes sure that the SCSI
mid-layer never tries to queue more than (SRP request limit) - 1 SCSI
commands to ib_srp. This improves performance for targets whose request
limit is less than or equal to SRP_NORMAL_REQ_SQ_SIZE by reducing the
number of BUSY responses reported by ib_srp to the SCSI mid-layer.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NDavid Dillow <dillowda@ornl.gov>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NDavid Dillow <dillowda@ornl.gov>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Use the net device's dev_id field to encode the port number of the pci
device.  This can be used to to associate a net device with the pci
device's port. The encoding is: dev_id = port - 1.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch adds support for SRP_CRED_REQ to avoid a lockup by targets
that use that mechanism to return credits to the initiator. This
prevents a lockup observed in the field where we would never add the
credits from the SRP_CRED_REQ to our current count, and would therefore
never send another command to the target.

Minimal support for SRP_AER_REQ is also added, as these messages can
also be used to convey additional credits to the initiator.

Based upon extensive debugging and code by Bart Van Assche and a bug
report by Chris Worley.
Signed-off-by: NDavid Dillow <dillowda@ornl.gov>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The transmit ring in ib_srp (srp_target.tx_ring) is currently only used
for allocating requests sent by the initiator to the target. This patch
prepares using that ring for allocation of both requests and responses.
Also, this patch differentiates the uses of SRP_SQ_SIZE, increases the
size of the IB send completion queue by one element and reserves one
transmit ring slot for SRP_TSK_MGMT requests.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NDavid Dillow <dillowda@ornl.gov>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The patch below updates broken web addresses in the kernel
Signed-off-by: NJustin P. Mattock <justinmattock@gmail.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Dimitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: NBen Pfaff <blp@cs.stanford.edu>
Acked-by: NHans J. Koch <hjk@linutronix.de>
Reviewed-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

IPoIB is IP-over-Infiniband link layer. In the case of IBoE, the link
layer is Ethernet and IP can work directly over Ethernet, so disable
IPoIB for non-IB_LINK_LAYER_INFINIBAND ports.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

IGMP processing is broken because the IPOIB does not set the
skb->pkt_type the right way for multicast traffic.  All incoming
packets are set to PACKET_HOST which means that igmp_recv() will
ignore the IGMP broadcasts/multicasts.

This in turn means that the IGMP timers are firing and are sending
information about multicast subscriptions unnecessarily.  In a large
private network this can cause traffic spikes.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Export req_lim via sysfs for debugging.
Signed-off-by: NBart Van Assche <bart.vanassche@gmail.com>
Acked-by: NDavid Dillow <dave@thedillows.org>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The current strategy in ib_srp for posting receive buffers is:

 * Post one buffer after channel establishment.
 * Post one buffer before sending an SRP_CMD or SRP_TSK_MGMT to the target.

As a result, only the first non-SRP_RSP information unit from the
target will be processed.  If that first information unit is an
SRP_T_LOGOUT, it will be processed.  On the other hand, if the
initiator receives an SRP_CRED_REQ or SRP_AER_REQ before it receives a
SRP_T_LOGOUT, the SRP_T_LOGOUT won't be processed.

We can fix this inconsistency by changing the strategy for posting
receive buffers to:

 * Post all receive buffers after channel establishment.
 * After a receive buffer has been consumed and processed, post it again.

A side effect is that the ib_post_recv() call is moved out of the SCSI
command processing path.  Since __srp_post_recv() is not called
directly any more, get rid of it and move the code directly into
srp_post_recv().  Also, move srp_post_recv() up in the file to avoid a
forward declaration.
Signed-off-by: NBart Van Assche <bart.vanassche@gmail.com>
Acked-by: NDavid Dillow <dave@thedillows.org>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Replace an open-coded dump of the receive buffer with a call to
print_hex_dump().
Signed-off-by: NBart Van Assche <bart.vanassche@gmail.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Sumeet Lahorani <sumeet.lahorani@oracle.com> reported that the IPoIB
child entries are world-writable; however we don't want ordinary users
to be able to create and destroy child interfaces, so fix them to be
writable only by root.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Cc: <stable@kernel.org>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Following commit 1437ce39 "ethtool:
Change ethtool_op_set_flags to validate flags", ethtool_op_set_flags
takes a third parameter and cannot be used directly as an
implementation of ethtool_ops::set_flags.

Changes nes and ipoib driver to pass in the appropriate value.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Acked-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We shouldn't free things here because we free them later.
The call tree looks like this:
	iser_connect() ==> initiating the connection establishment
and later
	iser_cma_handler() => iser_route_handler() => iser_create_ib_conn_res()
if we fail here, eventually iser_conn_release() is called, resulting
in a double free.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The iser connection teardown flow isn't over until the underlying
Connection Manager (e.g the IB CM) delivers a disconnected or timeout
event through the RDMA-CM.  When the remote (target) side isn't
reachable, e.g when some HW e.g port/hca/switch isn't functioning or
taken down administratively, the CM timeout flow is used and the event
may be generated only after relatively long time -- on the order of
tens of seconds.

The current iser code exposes this possibly long delay to higher
layers, specifically to the iscsid daemon and iscsi kernel stack. As a
result, the iscsi stack doesn't respond well: this low-level CM delay
is added to the fail-over time under HA schemes such as the one
provided by DM multipath through the multipathd(8) service.

This patch enhances the reference counting scheme on iser's IB
connections so that the disconnect flow initiated by iscsid from user
space (ep_disconnect) doesn't wait for the CM to deliver the
disconnect/timeout event.  (The connection teardown isn't done from
iser's view point until the event is delivered)

The iser ib (rdma) connection object is destroyed when its reference
count reaches zero.  When this happens on the RDMA-CM callback
context, extra care is taken so that the RDMA-CM does the actual
destroying of the associated ID, since doing it in the callback is
prohibited.

The reference count of iser ib connection normally reaches three,
where the <ref, deref> relations are

 1. conn <init, terminate>
 2. conn <bind, stop/destroy>
 3. cma id <create, disconnect/error/timeout callbacks>

With this patch, multipath fail-over time is about 30 seconds, while
without this patch, multipath fail-over time is about 130 seconds.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The iscsi connection object life cycle includes binding and unbinding
(conn_stop) to/from the iscsi transport connection object.  Since
iscsi connection objects are recycled, at the time the transport
connection (e.g iser's IB connection) is released, it is not valid to
touch the iscsi connection tied to the transport back-pointer since it
may already point to a different transport connection.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add handler to handle events such as port up and down.  This is useful
when testing high-availability schemes such as multi-pathing.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Converts the list and the core manipulating with it to be the same as uc_list.

+uses two functions for adding/removing mc address (normal and "global"
 variant) instead of a function parameter.
+removes dev_mcast.c completely.
+exposes netdev_hw_addr_list_* macros along with __hw_addr_* functions for
 manipulation with lists on a sandbox (used in bonding and 80211 drivers)
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Finally this bit can be removed. Currently, after the bonding driver is
changed/fixed (32a806c1 net-next-2.6),
that's not possible for an addr with different length than dev->addr_len
to be present in list. Removing this check as in new mc_list there will be
no addrlen in the record.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Print the return code of ib_post_send() if it fails to make these
debugging messages more useful.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The IPoIB UD QP reports send completions to priv->send_cq, which is
usually left unarmed; it only gets armed when the number of
outstanding send requests reaches the size of the TX queue. This
arming is done only in the send path for the UD QP.  However, when
sending CM packets, the net queue may be stopped for the same reasons
but no measures are taken to recover the UD path from a lockup.

Consider this scenario: a host sends high rate of both CM and UD
packets, with a TX queue length of N.  If at some time the number of
outstanding UD packets is more than N/2 and the overall outstanding
packets is N-1, and CM sends a packet (making the number of
outstanding sends equal N), the TX queue will be stopped.  When all
the CM packets complete, the number of outstanding packets will still
be higher than N/2 so the TX queue will not be restarted.

Fix this by calling ib_req_notify_cq() when the queue is stopped in
the CM path.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

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: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJayamohan Kallickal <jayamohank@serverengines.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Instead of repeating the error unwinding steps in each place an error
can be detected, use the common idiom of gotos into an error flow.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

We can reduce the number of IB interrupts from two interrupts per
srp_queuecommand() call to one by using separate CQs for send and
receive completions and processing send completions by polling every
time a TX IU is allocated.

Receive completion events still trigger an interrupt.
Signed-off-by: NBart Van Assche <bart.vanassche@gmail.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Apparently bogus mc address can break IPOIB multicast processing. Therefore
returning the check for addrlen back until this is resolved in bonding (I don't
see any other point from where mc address with non-dev->addr_len length can came
from).
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Due to the loop complexicity in nes_nic.c, I'm using char* to copy mc addresses
to it.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the iSER receive completion flow takes the session lock
twice.  Optimize it to avoid the first one by letting
iser_task_rdma_finalize() be called only from the cleanup_task
callback invoked by iscsi_free_task, thus reducing the contention on
the session lock between the scsi command submission to the scsi
command completion flows.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

libiscsi passthrough mode invokes the transport xmit calls directly
without first going through an internal queue, unlike the other mode,
which uses a queue and a xmitworker thread.  Now that the "cant_sleep"
prerequisite of iscsi_host_alloc is met, move to use it.  Handling
xmit errors is now done by the passthrough flow of libiscsi.  Since
the queue/worker aren't used in this mode, the code that schedules the
xmitworker is removed.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Remove unnecessary checks for the IB connection state and for QP
overflow, as conn state changes are reported by iSER to libiscsi and
handled there. QP overflow is theoretically possible only when
unsolicited data-outs are used; anyway it's being checked and handled
by HW drivers.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Two minor flows in iSER's data path still use allocations; move them
to be atomic as a preperation step towards moving to use libiscsi
passthrough mode.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Simplify and shrink the logic/code used for the send descriptors.
Changes include removing struct iser_dto (an unnecessary abstraction),
using struct iser_regd_buf only for handling SCSI commands, using
dma_sync instead of dma_map/unmap, etc.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Use a different CQ for send completions, where send completions are
polled by the interrupt-driven receive completion handler.  Therefore,
interrupts aren't used for the send CQ.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>