Commit Graph

914 Commits

Author SHA1 Message Date
Michael S. Tsirkin 608d8268be IB/mthca: Fix data corruption after FMR unmap on Sinai
In mthca_arbel_fmr_unmap(), the high bits of the key are masked off.
This gets rid of the effect of adjust_key(), which makes sure that
bits 3 and 23 of the key are equal when the Sinai throughput
optimization is enabled, and so it may happen that an FMR will end up
with bits 3 and 23 in the key being different.  This causes data
corruption, because when enabling the throughput optimization, the
driver promises the HCA firmware that bits 3 and 23 of all memory keys
will always be equal.

Fix by re-applying adjust_key() after masking the key.

Thanks to Or Gerlitz for reproducing the problem, and Ariel Shahar for
help in debug.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-04-16 14:10:55 -07:00
Steve Wise 1ca19770c5 RDMA/cxgb3: Add set_tcb_rpl_handler
As of commit 6cdbd77e ("cxgb3 - missing CPL hanler and register
setting."), the cxgb3 ethernet NIC driver no longer handles SET_TCB
replies, so we need to do it in the iWARP driver.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Acked-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-04-12 10:37:11 -07:00
Michael S. Tsirkin 6371ea3d48 IPoIB/cm: Fix DMA direction typo
Receive buffers need to be mapped with DMA_FROM_DEVICE.  Incorrectly
mapping with DMA_TO_DEVICE causes a hard lock on ppc64 machines with
an IOMMU.

This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=431>

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-04-10 08:58:30 -07:00
Erez Zilber 1d426d6418 IB/iser: Don't defer connection failure notification to workqueue
When a connection is terminated asynchronously from the iSCSI layer's
perspective, iSER needs to notify the iSCSI layer that the connection
has failed.  This is done using a workqueue (switched to from the iSER
tasklet context).  Meanwhile, the connection object (that holds the
work struct) is released.  If the workqueue function wasn't called
yet, it will be called later with a NULL pointer, which will crash the
kernel.

The context switch (tasklet to workqueue) is not required, and
everything can be done from the iSER tasklet. This eliminates the NULL
work struct bug (and simplifies the code).

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-04-05 09:46:04 -07:00
Linus Torvalds a26b5fce06 Merge branch 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband:
  IB/iser: Handle aborting a command after it is sent
  IB/mthca: Fix thinko in init_mr_table()
  RDMA/cxgb3: Fix resource leak in cxio_hal_init_ctrl_qp()
2007-03-28 14:00:01 -07:00
Erez Zilber 3104a2175d IB/iser: Handle aborting a command after it is sent
The SCSI midlayer may abort a command that was already sent.  If the
initiator is still trying to send the command (or data-out PDUs for
that command), the QP may time out after the midlayer times
out. Therefore, when aborting the command, iSER may still have
references for the command's buffers.  When sending these PDUs, the
sends will complete with an error and their resources will be released
then.

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-26 16:35:09 -07:00
Michael S. Tsirkin 0264d88531 IB/mthca: Fix thinko in init_mr_table()
Commit c20e20ab ("IB/mthca: Merge MR and FMR space on 64-bit systems")
swapped the number of MTTs and MPTs when initializing the MR table. As
a result, we get a kernel oops when the number of MTT segments
allocated exceeds 0x20000.

Noted by Troy Benjegerdes <troy@scl.ameslab.gov>, and reproduced by
Dotan Barak <dotanb@mellanox.co.il>.  This fixes
https://bugs.openfabrics.org/show_bug.cgi?id=490

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-26 15:59:32 -07:00
Steve Wise ed6ee5178e RDMA/cxgb3: Fix resource leak in cxio_hal_init_ctrl_qp()
This was spotted by the Coverity checker (CID 1554).

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-26 15:54:40 -07:00
Alexey Kuznetsov ecbb416939 [NET]: Fix neighbour destructor handling.
->neigh_destructor() is killed (not used), replaced with
->neigh_cleanup(), which is called when neighbor entry goes to dead
state. At this point everything is still valid: neigh->dev,
neigh->parms etc.

The device should guarantee that dead neighbor entries (neigh->dead !=
0) do not get private part initialized, otherwise nobody will cleanup
it.

I think this is enough for ipoib which is the only user of this thing.
Initialization private part of neighbor entries happens in ipib
start_xmit routine, which is not reached when device is down.  But it
would be better to add explicit test for neigh->dead in any case.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-25 18:48:01 -07:00
Michael S. Tsirkin 77d8e1efea IB/ipoib: Fix thinko in packet length checks
The packet length checks in ipoib are broken: we add 4 bytes (IPoIB
encapsulation header) when sending a packet, not 20 bytes (hardware
address length) to each packet.  Therefore, if connected mode is
enabled so that the interface MTU is larger than the multicast MTU,
IPoIB may end up trying to send too-long multicast packets.  For
example, multicast is broken if a message of size 2048 bytes is sent
on an interface with UD MTU 2048, because 2048 is bigger than the real
limit of 2044 but the code tests against the wrong limit of 2060.

This patch fixes <https://bugs.openfabrics.org/show_bug.cgi?id=418>,
submitted by Scott Weitzenkamp <sweitzen@cisco.com>.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-22 14:40:16 -07:00
Michael S. Tsirkin d04d01b113 IPoIB: Fix use-after-free in path_rec_completion()
The connected mode code added the possibility that an neigh struct
gets freed in the list_for_each_entry() loop in path_rec_completion(),
which causes a use-after-free.  Fix this by changing to the _safe
variant of the list walking macro.

This was spotted by the Coverity checker (CID 1567).

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-22 14:40:16 -07:00
Joachim Fenkes 73b9e9870f IB/ehca: Make scaling code work without CPU hotplug
eHCA scaling code must not depend on register_cpu_notifier() if
CONFIG_HOTPLUG_CPU is not set, so put all related code into #ifdefs.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-22 14:40:16 -07:00
Steve Wise d601347188 RDMA/cxgb3: Handle build_phys_page_list() failure in iwch_reregister_phys_mem()
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-22 14:40:16 -07:00
Bryan O'Sullivan fae8773b73 IB/ipath: Check return value of lookup_one_len
This fixes kernel.org bug 8003.

Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-22 14:40:15 -07:00
Sean Hefty e07832b662 IPoIB: Fix race in detaching from mcast group before attaching
There's a race between ipoib_mcast_leave() and ipoib_mcast_join_finish()
where we can try to detach from a multicast group before we've
attached to it.  Fix this by reordering the code in ipoib_mcast_leave
to free the multicast group first, which waits for the multicast
callback thread (which calls ipoib_mcast_join_finish()) to complete
before detaching from the group.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-22 14:32:09 -07:00
Michael S. Tsirkin 60a596dab7 IPoIB/cm: Fix reaping of stale connections
The sense of the time_after_eq() test in ipoib_cm_stale_task() is
reversed so that only non-stale connections are reaped.  Fix this by
changing to time_before_eq().

Noticed by Pradeep Satyanarayana <pradeep@us.ibm.com>.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-22 14:32:09 -07:00
Al Viro 62577fa324 [PATCH] fix ipath_dma_free_coherent() prototype
method gets u64, not dma_addr_t

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-14 15:27:49 -07:00
Shirley Ma 55c9adde13 IPoIB: Turn on interface's carrier after broadcast group is joined
Do netif_carrier_on() right after the IPv4 broadcast multicast group
is joined, rather than waiting for all of the initial set of multicast
group joins to finish.  This allows at least IPv4 traffic to limp
along on broken fabrics where not all multicast groups can be joined.

Signed-off-by: Shirley Ma <xma@us.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-08 14:59:30 -08:00
Sean Hefty 3492856e33 RDMA/ucma: Avoid sending reject if backlog is full
Change the returned error code to ENOMEM if the connection event
backlog is full.  This prevents the ib_cm from issuing a reject
on the connection, which can allow retries to succeed.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 14:58:11 -08:00
Steve Wise e64518f373 RDMA/cxgb3: Fix MR permission problems
Fix memory region permission problems:

- remove useless and redundant iwch_mem_perms enum.

- create ib_to_tpt_access_rights() for mapping ib access rights
  to T3 TPT permissions.

- create ib_to_mwbind_access_rights() for mapping ib access rights
  to T3 MWBIND WR permissions.

- fix up the mem reg code to utilize the new functions.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:51:02 -08:00
Steve Wise 1f6a849b7c RDMA/cxgb3: Don't reuse skbs that are non-linear or cloned
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:50:57 -08:00
Steve Wise 8cfccf02bb RDMA/cxgb3: Squelch logging AE errors
Only print one AE error for a given connection in the kernel log.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:50:53 -08:00
Steve Wise adf376b370 RDMA/cxgb3: Stop EP timer when MPA exchange is aborted by peer
Stop the endpoint timer when the MPA exchange is aborted by the peer.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:50:49 -08:00
Steve Wise 2df50da00e RDMA/cxgb3: Move QP to error on destroy if the state is IDLE
Change iwch_destroy_qp() to always move the QP to ERROR and let
iwch_modify_qp() decide what to do.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:50:45 -08:00
Steve Wise 42e3175354 RDMA/cxgb3: Fixes for "normal close" failures
Fixes for "normal close" failures:

- Start normal close timer when moving to CLOSING state.
- Handle ABORTING state in close_con_rpl().
- Stop timer correctly on abort during a normal close.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:50:37 -08:00
David Miller c3bb1092c8 RDMA/cxgb3: Fix build on sparc64
cxgb3 uses dma_alloc_coherent() et al. thus needs linux/dma-mapping.h
include in order to build reliably.

Noticed on sparc64.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:45:57 -08:00
Sean Hefty cb164b8c6a RDMA/cma: Initialize rdma_bind_list in cma_alloc_any_port()
The struct rdma_bind_list fields for hlist are not being initialized,
resulting in a corrupted list.  Fix this by using kzalloc() to make
sure all pointers are NULL.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 12:41:44 -08:00
Steve Wise aeb100e246 RDMA/cxgb3: Don't use mm after it's freed in iwch_mmap()
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 11:48:17 -08:00
Steve Wise 7d526e6b2c RDMA/cxgb3: Start ep timer on a MPA reject
If the consumer rejects the connection we end up under-referencing the
endpoint structure.  The fix is to call iwch_ep_disconnect() instead
of the low level disconnect functions so that the endpoint close timer
is started correctly.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-06 11:47:05 -08:00
Roland Dreier 88171cfed5 IB/mthca: Fix error path in mthca_alloc_memfree()
The garbled logic in mthca_alloc_memfree() causes it to return 0, even
if it fails to allocate all doorbell records.  Fix it to return -ENOMEM
when it fails.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-01 13:17:14 -08:00
Hoang-Nam Nguyen 31726798bd IB/ehca: Fix sync between completion handler and destroy cq
This patch fixes two issues reported by Roland Dreier and Christoph Hellwig:

- Mismatched sync/locking between completion handler and destroy cq We
  introduced a counter nr_events per cq to track number of irq events
  seen. This counter is incremented when an event queue entry is seen
  and decremented after completion handler has been called regardless
  if scaling code is active or not. Note that nr_callbacks tracks
  number of events assigned to a cpu and both counters can potentially
  diverge.

  The sync between running completion handler and destroy cq is done
  by using the global spin lock ehca_cq_idr_lock.

- Replace yield by wait_event on the counter above to become zero.

Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-03-01 13:04:05 -08:00
Roland Dreier a27cbe8782 IPoIB: Only handle async events for one port
An asynchronous event carries the port number that the event occurred
on, so there's no reason for an IPoIB interface to process an event
associated with a different local HCA port.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-27 07:37:49 -08:00
Roland Dreier 843613b047 IPoIB: Correct debugging output when path record lookup fails
If path_rec_completion() is passed a non-NULL path record pointer
along with an unsuccessful status value, the tracing code incorrectly
prints the (invalid) DLID from the path record rather than the more
interesting status code.  The actual logic of the function correctly
uses the path record only if the status indicates a successful lookup.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-26 12:57:08 -08:00
Steve Wise 2f236735fd RDMA/cxgb3: Stop the EP Timer on BAD CLOSE
Stop the ep timer in ec_status() if the status indicates a
bad close.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-23 13:12:48 -08:00
Adrian Bunk 2b540355cd RDMA/cxgb3: cleanups
- don't mark static functions in C files as inline - gcc should know
  best whether inlining makes sense
- never compile the unused cxio_dbg.c
- make the following needlessly global functions static:
  - cxio_hal.c: cxio_hal_clear_qp_ctx()
  - iwch_provider.c: iwch_get_qp()
- remove the following unused global functions:
  - cxio_hal.c: cxio_allocate_stag()
  - cxio_resource.: cxio_hal_get_rhdl()
  - cxio_resource.: cxio_hal_put_rhdl()

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-23 13:10:43 -08:00
Sean Hefty 1836854f25 RDMA/cma: Remove unused node_guid from cma_device structure
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-22 17:54:35 -08:00
Sean Hefty e971b8cd19 IB/cm: Remove ca_guid from cm_device structure
The cm_device references an ib_device, which already contains the node_guid.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-22 17:54:33 -08:00
Sean Hefty 962063e64b RDMA/cma: Request reversible paths only
The rdma_cm requires that path records be reversible.  Set the
reversible bit when issuing an path record query.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-22 17:54:07 -08:00
Sean Hefty 47645d8d25 IB/core: Set hop limit in ib_init_ah_from_wc correctly
The hop_limit value in the ah_attr should be 0xFF, not the value read
from the received GRH (which should be 0).  See 13.5.4.4 in the 1.2 IB
spec.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-22 17:54:02 -08:00
Roland Dreier aaf1aef55f IB/uverbs: Return correct error for invalid PD in register MR
If no matching PD is found in ib_uverbs_reg_mr(), then the function
jumps to err_release without setting the return value ret.  This means
that ret will hold the return value of the call to ib_umem_get() a few
lines earlier; if the function reaches the point where it looks for
the PD, we know that ib_umem_get() must have returned 0, so
ib_uverbs_reg_mr() ends up return 0 for a bad PD ID.  Fix this by
setting ret to -EINVAL before jumping to the exit path when no PD is
found.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-22 13:16:51 -08:00
Roland Dreier 658bcef619 IPoIB: Remove unused local_rate tracking
Now that low-level drivers handle the conversion from an absolute rate
to a relative rate, there's no need for the IPoIB driver to keep track
of the local port's data rate.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-21 20:28:05 -08:00
Michael S. Tsirkin 1812063ba3 IPoIB/cm: Improve small message bandwidth
Avoid the overhead of freeing/reallocating and mapping/unmapping for
DMA pages that have not been written to by hardware.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-20 20:16:14 -08:00
Adrian Bunk c9add6ec56 IB/mthca: Make 2 functions static
This patch makes the needlessly global functions mthca_tavor_write_mtt_seg()
and mthca_arbel_write_mtt_seg() static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-20 20:12:02 -08:00
Linus Torvalds 874ff01bd9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits)
  Documentation/kernel-docs.txt update.
  arch/cris: typo in KERN_INFO
  Storage class should be before const qualifier
  kernel/printk.c: comment fix
  update I/O sched Kconfig help texts - CFQ is now default, not AS.
  Remove duplicate listing of Cris arch from README
  kbuild: more doc. cleanups
  doc: make doc. for maxcpus= more visible
  drivers/net/eexpress.c: remove duplicate comment
  add a help text for BLK_DEV_GENERIC
  correct a dead URL in the IP_MULTICAST help text
  fix the BAYCOM_SER_HDX help text
  fix SCSI_SCAN_ASYNC help text
  trivial documentation patch for platform.txt
  Fix typos concerning hierarchy
  Fix comment typo "spin_lock_irqrestore".
  Fix misspellings of "agressive".
  drivers/scsi/a100u2w.c: trivial typo patch
  Correct trivial typo in log2.h.
  Remove useless FIND_FIRST_BIT() macro from cardbus.c.
  ...
2007-02-19 13:29:02 -08:00
Robert P. J. Day d08df601a3 Various typo fixes.
Correct mis-spellings of "algorithm", "appear", "consistent" and
(shame, shame) "kernel".

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-02-17 19:07:33 +01:00
Roland Dreier 7084f8429c IB/core: Set static rate in ib_init_ah_from_path()
The static rate from the path record should be put into the address
vector -- a long time ago the rate in the address attributes needed to
be a relative rate, which required more munging, but now that the
conversion from absolute to relative is done in the low-level driver,
it's easy for ib_init_ah_from_path() to put the absolute rate in.

Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-16 15:31:24 -08:00
Roland Dreier 630e61f2fa IB/ipath: Make ipath_map_sg() static
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-16 14:58:08 -08:00
Roland Dreier 38abaa63bf IB/core: Fix sparse warnings about shadowed declarations
Change a couple of variable names to avoid sparse warnings about
symbols being shadowed.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-16 14:41:14 -08:00
Sean Hefty c8f6a362bf RDMA/cma: Add multicast communication support
Extend rdma_cm to support multicast communication.  Multicast support
is added to the existing RDMA_PS_UDP port space, as well as a new
RDMA_PS_IPOIB port space.  The latter port space allows joining the
multicast groups used by IPoIB, which enables offloading IPoIB traffic
to a separate QP.  The port space determines the signature used in the
MGID when joining the group.  The newly added RDMA_PS_IPOIB also
allows for unicast operations, similar to RDMA_PS_UDP.

Supporting the RDMA_PS_IPOIB requires changing how UD QPs are initialized,
since we can no longer assume that the qkey is constant.  This requires
saving the Q_Key to use when attaching to a device, so that it is
available when creating the QP.  The Q_Key information is exported to
the user through the existing rdma_init_qp_attr() interface.

Multicast support is also exported to userspace through the rdma_ucm.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-16 14:29:07 -08:00
Sean Hefty faec2f7b96 IB/sa: Track multicast join/leave requests
The IB SA tracks multicast join/leave requests on a per port basis and
does not do any reference counting: if two users of the same port join
the same group, and one leaves that group, then the SA will remove the
port from the group even though there is one user who wants to stay a
member left.  Therefore, in order to support multiple users of the
same multicast group from the same port, we need to perform reference
counting locally.

To do this, add an multicast submodule to ib_sa to perform reference
counting of multicast join/leave operations.  Modify ib_ipoib (the
only in-kernel user of multicast) to use the new interface.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-16 14:20:02 -08:00