Automatically queue MRA message to decrease the number of retries sent
by the remote side during connection establishment. This also has the
effect of increasing the overall connection timeout without using a
longer retry time in the case of dropped packets.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The IB CM provides a message received acknowledged (MRA) message that
can be sent to indicate that a REQ or REP message has been received, but
will require more time to process than the timeout specified by those
messages. In many cases, the application may not know how long it will
take to respond to a CM message, but the majority of the time, it will
usually respond before a retry has been sent. Rather than sending an
MRA in response to all messages just to handle the case where a longer
timeout is needed, it is more efficient to queue the MRA for sending in
case a duplicate message is received.
This avoids sending an MRA when it is not needed, but limits the number
of times that a REQ or REP will be resent. It also provides for a
simpler implementation than generating the MRA based on a timer event.
(That is, trying to send the MRA after receiving the first REQ or REP if
a response has not been generated, so that it is received at the remote
side before a duplicate REQ or REP has been received)
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
ib_uverbs_release_event_file() is only used in uverbs_main.c, so make it
static to that file. Also move the definition before the first use, so
a forward declaration is not needed.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The declaration of struct ib_user_mad_reg_req.method_mask[] exported
to userspace was an array of __u32, but the kernel internally treated
it as a bitmap made up of longs. This makes a difference for 64-bit
big-endian kernels, where numbering the bits in an array of__u32 gives:
|31.....0|63....31|95....64|127...96|
while numbering the bits in an array of longs gives:
|63..............0|127............64|
64-bit userspace can handle this by just treating method_mask[] as an
array of longs, but 32-bit userspace is really stuck: the meaning of
the bits in method_mask[] depends on whether the kernel is 32-bit or
64-bit, and there's no sane way for userspace to know that.
Fix this by updating <rdma/ib_user_mad.h> to make it clear that
method_mask[] is an array of longs, and using a compat_ioctl method to
convert to an array of 64-bit longs to handle the 32-on-64 problem.
This fixes the interface description to match existing behavior (so
working binaries continue to work) in almost all situations, and gives
consistent semantics in the case of 32-bit userspace that can run on
either a 32-bit or 64-bit kernel, so that the same binary can work for
both 32-on-32 and 32-on-64 systems.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add support for setting the P_Key index of sent MADs and getting the
P_Key index of received MADs. This requires a change to the layout of
the ABI structure struct ib_user_mad_hdr, so to avoid breaking
compatibility, we default to the old (unchanged) ABI and add a new
ioctl IB_USER_MAD_ENABLE_PKEY that allows applications that are aware
of the new ABI to opt into using it.
We plan on switching to the new ABI by default in a year or so, and
this patch adds a warning that is printed when an application uses the
old ABI, to push people towards converting to the new ABI.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Reviewed-by: Sean Hefty <sean.hefty@intel.com>
Reviewed-by: Hal Rosenstock <hal@xsigo.com>
I was looking at the code for multicast.c and noticed that
ib_sa_join_multicast() calls queue_join() which puts the
request at the front of the group->pending_list. If this
is a second request, it seems like it would interfere with
process_join_error() since group->last_join won't point
to the member at the head of the pending_list. The sequence
would thus be:
1. ib_sa_join_multicast()
puts member1 on head of pending_list and starts work thread
2. mcast_work_handler()
calls send_join() which sets group->last_join to member1
3. ib_sa_join_multicast()
puts member2 on head of pending_list
4. join operation for member1 receives failures response from SA.
5. join_handler() is called with error status
6. process_join_error() fails to process member1 since
it doesn't match the first entry in the group->pending_list.
The impact is that the failed join request is tossed. The second
request is processed, and after it completes, the original request ends
up being retried.
This change also results in join requests being processed in FIFO
order.
Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Calling arp_send() to initiate neighbour discovery (ND) doesn't do the
full ND protocol. Namely, it doesn't handle retransmitting the arp
request if it is dropped. The function neigh_event_send() does all
this. Without doing full ND, RDMA address resolution fails in the
presence of dropped ARP broadcast packets.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Acked-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
During ib_umem_get(), determine whether all pages from the memory
region are hugetlb pages and report this in the "hugetlb" member.
Low-level drivers can use this information if they need it.
Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Export the ability to set the type of service to user space. Model
the interface after setsockopt.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Provide support to specify a type of service for a communication
identifier. A new function call is used when dealing with IPv4
addresses. For IPv6 addresses, the ToS is specified through the
traffic class field in the sockaddr_in6 structure.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
[ The comments Eitan Zahavi and myself have made over the v1 post at
<http://lists.openfabrics.org/pipermail/general/2007-August/039247.html>
were fully addressed. ]
Reviewed-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The QoS annex defines new fields for path records. Add them to the
ib_sa for consumers that want to use them.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Reviewed-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
ib_create_send_mad() returns an error code pointer on error, not NULL.
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
A number of printks in fmr_pool.c dont have newlines, eg:
fmr_create failed for FMR 0<5>FS-Cache: Loaded
Fix them up.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Fix sparse warning
drivers/infiniband/core/device.c:142:6: warning: incorrect type in argument 1 (different signedness)
drivers/infiniband/core/device.c:142:6: expected unsigned long const *addr
drivers/infiniband/core/device.c:142:6: got long *[assigned] inuse
by making the local variable inuse unsigned. Does not affect generated
code at all.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
After moving the definition of struct ib_umem_chunk from ib_verbs.h to
ib_umem.h there isn't any reason for the macro IB_UMEM_MAX_PAGE_CHUNK
to stay in ib_verbs.h. Move the macro to umem.c, the only place where
it is used.
Signed-off-by: Dotan Barak <dotanb@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The address handle associated with dual-sided RMPP direction switch
ACKs is never destroyed. Free the AH for ACKs which fall into this
category.
Problem was reported by Dotan Barak <dotanb@dev.mellanox.co.il>.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Nothing looks at the return value of agent_send_response(), so there's
no point in returning anything.
Signed-off-by: Hal Rosenstock <hal.rosenstock@gmail.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
If agent_send_response() returns an error, we shouldn't do anything
differently than if it succeeds; setting response to NULL just means
that the response buffer gets leaked.
Signed-off-by: Suresh Shelvapille <suri@baymicrosystems.com>
Signed-off-by: Hal Rosenstock <hal.rosenstock@gmail.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
If ib_mad_recv_done_handler() fails to allocate response, then it just
printed a warning and continued, which leads to an oops if the MAD is
being handled for a switch device, because the switch code uses
response without checking for NULL. Fix this by bailing out of the
function if the allocation fails.
Signed-off-by: Suresh Shelvapille <suri@baymicrosystems.com>
Signed-off-by: Hal Rosenstock <hal.rosenstock@gmail.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Now that ib_find_pkey() ignores the membership bit of P_Keys, there's no
need for ib_sa to look for both 0x7fff and 0xffff in a port's P_Key table.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
ib_find_pkey() is used as a replacement for ib_find_cached_pkey(), and
the original function ignored the membership bit when searching for a
P_Key, so ib_find_pkey() should ignore the bit too.
In particular, IPoIB turns on the P_Key membership bit of limited
membership P_Keys when creating a child interface and looks for the
full membership P_key. This broke if a port was a partial member of a
partition when IPoIB switched from ib_find_cached_pkey() to
ib_find_pkey(), and this change fixes things again.
Signed-off-by: Moni Shoua <monis@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).
Here is a short excerpt of the semantic patch performing
this transformation:
@@
type T2;
expression x;
identifier f,fld;
expression E;
expression E1,E2;
expression e1,e2,e3,y;
statement S;
@@
x =
- kmalloc
+ kzalloc
(E1,E2)
... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
- memset((T2)x,0,E1);
@@
expression E1,E2,E3;
@@
- kzalloc(E1 * E2,E3)
+ kcalloc(E1,E2,E3)
[akpm@linux-foundation.org: get kcalloc args the right way around]
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg KH <greg@kroah.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Local write permission makes no sense as part of the QP access flags,
since the access flags only control what the remote end of the
connection is allowed to do. Remove the code in the RDMA CM that
initializes qp_access_flags with IB_ACCESS_LOCAL_WRITE.
Signed-off-by: Dotan Barak <dotanb@mellanox.co.il>
Acked-by: Sean Hefty <sean.hefty@intel.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (76 commits)
IB: Update MAINTAINERS with Hal's new email address
IB/mlx4: Implement query SRQ
IB/mlx4: Implement query QP
IB/cm: Send no match if a SIDR REQ does not match a listen
IB/cm: Fix handling of duplicate SIDR REQs
IB/cm: cm_msgs.h should include ib_cm.h
IB/cm: Include HCA ACK delay in local ACK timeout
IB/cm: Use spin_lock_irq() instead of spin_lock_irqsave() when possible
IB/sa: Make sure SA queries use default P_Key
IPoIB: Recycle loopback skbs instead of freeing and reallocating
IB/mthca: Replace memset(<addr>, 0, PAGE_SIZE) with clear_page(<addr>)
IPoIB/cm: Fix warning if IPV6 is not enabled
IB/core: Take sizeof the correct pointer when calling kmalloc()
IB/ehca: Improve latency by unlocking after triggering the hardware
IB/ehca: Notify consumers of LID/PKEY/SM changes after nondisruptive events
IB/ehca: Return QP pointer in poll_cq()
IB/ehca: Change idr spinlocks into rwlocks
IB/ehca: Refactor sync between completions and destroy_cq using atomic_t
IB/ehca: Lock renaming, static initializers
IB/ehca: Report RDMA atomic attributes in query_qp()
...
sysfs is now completely out of driver/module lifetime game. After
deletion, a sysfs node doesn't access anything outside sysfs proper,
so there's no reason to hold onto the attribute owners. Note that
often the wrong modules were accounted for as owners leading to
accessing removed modules.
This patch kills now unnecessary attribute->owner. Note that with
this change, userland holding a sysfs node does not prevent the
backing module from being unloaded.
For more info regarding lifetime rule cleanup, please read the
following message.
http://article.gmane.org/gmane.linux.kernel/510293
(tweaked by Greg to not delete the field just yet, to make it easier to
merge things properly.)
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If a SIDR REQ does not match a listen, we should reply with status
value 1 (service ID not supported), rather than dropping through to
the default case of status 2 (rejected by service provider).
Doing this also fixes a bug where the cm_id_priv is removed from the
remote_sidr_table twice.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Fix handling to duplicate SIDR REQs to avoid sending a reject if a
duplicate is detected. Duplicates should just be silently discarded.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
cm_msgs.h uses definitions from ib_cm.h. Include it directly, rather
than depending on a specific include order.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The IB CM should include the HCA ACK delay when calculating the local
ACK timeout value to use for RC QPs. If the HCA ACK delay is large
enough relative to the packet life time, then if it is not taken into
account, the calculated timeout value ends up being too small, which
can result in "retry exceeded" errors.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The ib_cm is a little over zealous about using spin_lock_irqsave,
when spin_lock_irq would do.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
MADs sent to the SA should use the the default P_Key (0x7fff/0xffff).
There's no requirement that the default P_Key is stored at index 0 in
the local P_Key table, so add code to the sa_query module to look up
the index of the default P_Key when creating an address handle for the
SA (which is done any time the P_Key table might change), and use this
index for all SA queries.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
When allocating out_mad in show_pma_counter(), take sizeof *out_mad
instead of sizeof *in_mad. It is true that today the type of in_mad
and out_mad are the same, but this patch will give us a cleaner code.
Signed-off-by: Dotan Barak <dotanb@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
gcc correctly warned:
drivers/infiniband/core/umem.c: In function 'ib_umem_get':
drivers/infiniband/core/umem.c:78: warning: 'ret' may be used uninitialized in this function
Set ret to 0 in case npages == 0 and the loop isn't entered at all.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Extend the SMI with switch (intermediate hop) support. Care has been
taken to ensure that the CA (and router) code paths are changed as
little as possible.
Signed-off-by: Suresh Shelvapille <suri@baymicrosystems.com>
Signed-off-by: Hal Rosenstock <halr@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
If ib_umem_release() is called after ib_uverbs_close() sets context->closing,
then a process can get stuck in a D state, because the code boils down to
if (down_write_trylock(&mm->mmap_sem))
down_write(&mm->mmap_sem);
which is obviously a stupid instant deadlock. Fix the code so that we
only try to take the lock once.
This bug was introduced in commit f7c6a7b5 ("IB/uverbs: Export
ib_umem_get()/ib_umem_release() to modules") which fortunately never
made it into a release, and was reported by Pete Wyckoff <pw@osc.edu>.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
next_port should be between sysctl_local_port_range[0] and [1].
However, it is initially set to a random value with get_random_bytes().
If the value is negative when treated as a signed integer, next_port
can end up outside the expected range because of the result of the %
operator being negative.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The ib_cm can incorrectly detect a stale connection (a new connection
request for a QPN that is already connected) as a duplicate connection
request. Separate the handling of potential duplicate REQs from stale
connections.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband:
IB/cm: Improve local id allocation
IPoIB/cm: Fix SRQ WR leak
IB/ipoib: Fix typos in error messages
IB/mlx4: Check if SRQ is full when posting receive
IB/mlx4: Pass send queue sizes from userspace to kernel
IB/mlx4: Fix check of opcode in mlx4_ib_post_send()
mlx4_core: Fix array overrun in dump_dev_cap_flags()
IB/mlx4: Fix RESET to RESET and RESET to ERROR transitions
IB/mthca: Fix RESET to ERROR transition
IB/mlx4: Set GRH:HopLimit when sending globally routed MADs
IB/mthca: Set GRH:HopLimit when building MLX headers
IB/mlx4: Fix check of max_qp_dest_rdma in modify QP
IB/mthca: Fix use-after-free on device restart
IB/ehca: Return proper error code if register_mr fails
IPoIB: Handle P_Key table reordering
IB/core: Use start_port() and end_port()
IB/core: Add helpers for uncached GID and P_Key searches
IB/ipath: Fix potential deadlock with multicast spinlocks
IB/core: Free umem when mm is already gone
The IB CM uses an idr for local id allocations, with a running counter
as start_id. This fails to generate distinct ids if
1. An id is constantly created and destroyed
2. A chunk of ids just beyond the current next_id value is occupied
This in turn leads to an increased chance of connection request being
mis-detected as a duplicate, sometimes for several retries, until
next_id gets past the block of allocated ids. This has been observed
in practice.
As a fix, remember the last id allocated and start immediately above it.
This also fixes a problem with the old code, where next_id might
overflow and become negative.
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Acked-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clean up ib_query_port() and ib_modify_port() slightly by using the
just-added start_port() and end_port() helpers.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add ib_find_gid() and ib_find_pkey() functions that use uncached device
queries. The calls might block but the returns are always up-to-date.
Cache P_Key and GID table lengths in core to avoid extra port info queries.
Signed-off-by: Yosef Etigin <yosefe@voltaire.com>
Acked-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Free umem when task's mm is already destroyed by the time
ib_umem_release gets called.
Found by Dotan Barak at Mellanox.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Several checks in the rdma_cm check against the state of the
cm_id, but only to validate that the cm_id is bound to an underlying
transport specific CM and an RDMA device. Make the check explicit
in what we're trying to check for, since we're not synchronizing
against the cm_id state.
This will allow a user to disconnect a cm_id or reject a connection
after receiving a device removal event.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The cma_iw_handler needs to validate the state of the rdma_cm_id before
processing a new connection request to ensure that a device removal is
not already being processed for the same rdma_cm_id. Without the state
check, the user can receive simultaneous callbacks for the same cm_id, or
a callback after they've destroyed the cm_id.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add a new routine and rename another to encapsulate common code for
synchronizing with device removal.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
When memory pinned with ib_umem_get() is released, ib_umem_release()
needs to subtract the amount of memory being unpinned from
mm->locked_vm. However, ib_umem_release() may be called with
mm->mmap_sem already held for writing if the memory is being released
as part of an munmap() call, so it is sometimes necessary to defer
this accounting into a workqueue.
However, the work struct used to defer this accounting is dynamically
allocated before it is queued, so there is the possibility of failing
that allocation. If the allocation fails, then ib_umem_release has no
choice except to bail out and leave the process with a permanently
elevated locked_vm.
Fix this by allocating the structure to defer accounting as part of
the original struct ib_umem, so there's no possibility of failing a
later allocation if creating the struct ib_umem and pinning memory
succeeds.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
