A few files had 0xa0 characters in comments.  Remove them so that the 
files are clean ASCII text.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Refactor the ehca changes from commit ed23a727 ("IB: Return "maybe
missed event" hint from ib_req_notify_cq()") so the queue arithmetic
is done in slightly fewer lines.  Also, move the spinlock flags into
the block they're used in.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland 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: NSuresh Shelvapille <suri@baymicrosystems.com>
Signed-off-by: NHal Rosenstock <halr@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If a page can't be allocated for the frag list of a skb, the code to
unmap the partially allocated list is off by one.  For exaple, if
'frags' equals one, i == 0, and the alloc_page() fails, then the old
loop would have unmapped mapping[1] which is uninitialized.  The same
would happen if the call to ib_dma_map_page() failed.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Acked-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

We need to keep a spare entry in the SRQ so that there always is a
next WQE available when posting receives (so that we can tell the
difference between a full queue and an empty queue).  So subtract 1
from the value HW gives us before reporting the limit on SRQ entries
to consumers.

Found by Mellanox QA.
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

It's completely unused.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

IPoIB connected mode currently rejects a connection request unless the
supported MTU is >= the local netdevice MTU. This breaks
interoperability with implementations that might have tweaked
IPOIB_CM_MTU, and there's real no longer a reason to do so: this test
is just a leftover from when we did not tweak MTU per-connection.  Fix
this by making the test as permissive as possible.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix a crasher bug in IPoIB CM: once a QP is in the RTR state, a
receive completion (or even an asynchronous error) might be observed
on this QP, so we have to initialize all of our receive data
structures before moving to the RTR state.

As an optimization (since modify_qp might take a long time), the
jiffies update done when moving RX to the passive_ids list is also
left in place to reduce the chance of the RX being misdetected as
stale.

This fixes bug <https://bugs.openfabrics.org/show_bug.cgi?id=662>.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland 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: NRoland Dreier <rolandd@cisco.com>

Inline data segments in send WQEs are not allowed to cross a 64 byte
boundary.  We use inline data segments to hold the UD headers for MLX
QPs (QP0 and QP1).  A send with GRH on QP1 will have a UD header that
is too big to fit in a single inline data segment without crossing a
64 byte boundary, so split the header into two inline data segments.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Upcoming firmware introduces command interface revision 3, which
changes the way port capabilities are queried and set.  Update the
driver to handle both the new and old command interfaces by adding a
new MLX4_FLAG_OLD_PORT_CMDS that it is set after querying the firmware
interface revision and then using the correct interface based on the
setting of the flag.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When compacting CQ entries, we need to set the correct value of the
ownership bit in case the value is different between the index we copy
the CQE from and the index we copy it to.

Found by Ronni Zimmerman of Mellanox.
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The calculation of max_inline_data in set_kernel_sq_size() is bogus,
since it doesn't take into account the fact that inline segments may
not cross a 64-byte boundary, and hence multiple inline segments will
probably need to be used to post large inline sends.

We don't support inline sends for kernel QPs anyway, so there's no
point in doing this calculation anyway, since the field is just zeroed
out a little later.  So just delete the bogus calculation.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

New ConnectX firmware introduces FW command interface revision 2,
which requires that for each QP, a chunk of send queue entries (the
"headroom") is kept marked as invalid, so that the HCA doesn't get
confused if it prefetches entries that haven't been posted yet.  Add
code to the driver to do this, and also update the user ABI so that
userspace can request that the prefetcher be turned off for userspace
QPs (we just leave the prefetcher on for all kernel QPs).

Unfortunately, marking send queue entries this way is confuses older
firmware, so we change the driver to allow only FW command interface
revisions 2.  This means that users will have to update their firmware
to work with the new driver, but the firmware is changing quickly and
the old firmware has lots of other bugs anyway, so this shouldn't be too
big a deal.

Based on a patch from Jack Morgenstein <jackm@dev.mellanox.co.il>.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Doing max(1, foo) where foo is u32 generates a warning, because 1 is a
signed constant.  Fix this by using 1U instead.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Cast the increment added to wq->tail when send completions are
processed to u16 to avoid using wrong values caused by standard
integer promotions.

The same bug was fixed in libmlx4 by Eli Cohen <eli@mellanox.co.il>.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

QPs attached to an SRQ must never have their own RQ, and QPs not
attached to SRQs must have an RQ with at least 1 entry.  Enforce all
of this in set_rq_size().

Based on a patch by Eli Cohen <eli@mellanox.co.il>.
Signed-off-by: NRoland 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: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The code in __mlx4_ib_modify_qp() overwrites context->params1 after
the RNR retry parameter is ORed in, which results in the RNR retry
parameter always being set to 0.  Fix this by moving where we OR in
the value to later in the function, after the initial assignment of
context->params1.

Found by the Mellanox firmware group.
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch converts the ipv4_devconf config members (everything except
sysctl) to an array.  This allows easier manipulation which will be
needed later on to provide better management of default config values.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

s/signifant/significant/
Signed-off-by: NRoland 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: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

commit 518b1646 ("IPoIB/cm: Fix SRQ WR leak") introduced a severe
performance regression on Mellanox cards, because keeping a QP in the
error state for extended periods of time moves hardware to the slow
path (until the QP is destroyed).  For example, MPI latency goes from
~3 usecs to ~7 usecs.

Fix this by posting a send WR on one of the QPs that are being
flushed, instead of using a separate drain QP that is kept in the
error state.

This fixes bug <https://bugs.openfabrics.org/show_bug.cgi?id=636>,
reported and bisected by Scott Weitzenkamp at Cisco and debugged by
Sasha Mikheev at Voltaire.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

mthca_free_err_wqe() currently treats both send and receive CQEs
identically if a QP is using an SRQ.  But for Tavor hardware, send
CQEs with error can be chained together even if the RQ is part of SRQ,
so we may miss some CQEs.

Fix by following the WQE chain for all send CQEs even for non-SRQ QPs.

This fixes crashes in IPoIB CM:
<https://bugs.openfabrics.org//show_bug.cgi?id=604>
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Since NAPI polling is disabled while ipoib_cm_dev_stop() is running,
ipoib_cm_dev_stop() must poll the CQ itself in order to see the
packets draining.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

time_after() was used backwards, so the timeout occurred immediately.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Due to a typo, the driver was reporting the wrong number of "actual send
WRs" after ehca_create_qp().
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

We need to initialize the owner bit of send queue WQEs to hardware 
ownership whenever the QP is modified from reset to init, not just 
when the QP is first allocated.  This avoids having the hardware 
process stale WQEs when the QP is moved to reset but not destroyed and 
then modified to init again. 
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If a QP is attached to a shared receive queue (SRQ), then it doesn't
have a receive queue (RQ).  So don't allocate an RQ doorbell (or map a
doorbell from userspace for userspace QPs) for that QP.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

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: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Acked-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

SRQ WR leakage has been observed with IPoIB/CM: e.g. flipping ports on
and off will, with time, leak out all WRs and then all connections
will start getting RNR NAKs.  Fix this in the way suggested by spec:
move the QP being destroyed to the error state, wait for "Last WQE
Reached" event and then post WR on a "drain QP" connected to the same
CQ.  Once we observe a completion on the drain QP, it's safe to call
ib_destroy_qp.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Trivial error message fixups.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland 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: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make mlx4_post_srq_recv() fail if the SRQ is full (head == tail).
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Pass the number of WQEs for the send queue and their size from userspace
to the kernel to avoid having to keep the QP size calculations in sync 
between the kernel driver and libmlx4.  This fixes a bug seen with the 
current mlx4_ib driver and current libmlx4 caused by a difference in the 
calculated sizes for SQ WQEs.  Also, this gives more flexibility for 
userspace to experiment with using multiple WQE BBs for a single SQ WQE.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

wr->opcode is invalid if it's >= ARRAY_SIZE(mlx4_ib_opcode), not just
strictly >.

This was spotted by the Coverity checker (CID 1643).
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

According to the IB spec, a QP can be moved from RESET back to RESET
or to the ERROR state, but mlx4 firmware does not support this and
returns an error if we try.  Fix the RESET to RESET transition by
just returning 0 without doing anything, and fix RESET to ERROR by
moving the QP from RESET to INIT with dummy parameters and then
transitioning from INIT to ERROR.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

According to the IB spec, a QP can be moved from RESET to the ERROR 
state, but mthca firmware does not support this and returns an error if 
we try.  Work around this FW limitation by moving the QP from RESET to
INIT with dummy parameters and then transitioning from INIT to ERROR.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This is the same issue discovered in mthca by Rolf Manderscheid
<rvm@obsidianresearch.com>.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Global CM packets used by rmda_cm were being sent with a GRH:hopLimit
of zero, causing them to be dropped by the router.  The problem is a
missing initialization of the hop_limit field in mthca_read_ah(),
which was called by build_mlx_header() when sending a MAD on QP1.
Signed-off-by: NRolf Manderscheid <rvm@obsidianresearch.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>