ib_ud_header_init() first clears header and then fills up the various
fields.  Later on, it tests header->immediate_present, which it has
already cleared, so the condition is always false.  Fix this by adding
an immediate_present parameter and setting header->immediate_present
as is done with grh_present.  Also remove unused calculation of
header_len.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

mthca_ib_lock_cqs()/mthca_ib_unlock_cqs() are helper functions that
lock/unlock both CQs attached to a QP in the proper order to avoid
AB-BA deadlocks.  Annotate this so sparse can understand what's going
on (and warn us if we misuse these functions).
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The MLX transport requires two extra gather entries for sends (one for
the header and one for the checksum at the end, as the comment says).
However the code checked that max_recv_sge was not too big, instead of
checking max_send_sge as it should have.  Fix the code to check the
correct condition.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Commit b18aad71 ("IB/mthca: Fix RESET to ERROR transition") added some
extra code to handle a QP state transition from RESET to ERROR.
However, the latest 1.2.1 version of the IB spec has clarified that
this transition is actually not allowed, so we can remove this extra
code again.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

They don't get updated by git and so they're worse than useless.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If the QP was moved to another state (such as SQE) by the hardware,
then after this change the user won't have to set the IBV_QP_CUR_STATE
mask in order to execute modify QP in order to recover from this state.
Signed-off-by: NDotan Barak <dotanb@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add a new IB_WR_SEND_WITH_INV send opcode that can be used to mark a
"send with invalidate" work request as defined in the iWARP verbs and
the InfiniBand base memory management extensions.  Also put "imm_data"
and a new "invalidate_rkey" member in a new "ex" union in struct
ib_send_wr. The invalidate_rkey member can be used to pass in an
R_Key/STag to be invalidated.  Add this new union to struct
ib_uverbs_send_wr.  Add code to copy the invalidate_rkey field in
ib_uverbs_post_send().

Fix up low-level drivers to deal with the change to struct ib_send_wr,
and just remove the imm_data initialization from net/sunrpc/xprtrdma/,
since that code never does any send with immediate operations.

Also, move the existing IB_DEVICE_SEND_W_INV flag to a new bit, since
the iWARP drivers currently in the tree set the bit.  The amso1100
driver at least will silently fail to honor the IB_SEND_INVALIDATE bit
if passed in as part of userspace send requests (since it does not
implement kernel bypass work request queueing).  Remove the flag from
all existing drivers that set it until we know which ones are OK.

The values chosen for the new flag is not consecutive to avoid clashing
with flags defined in the XRC patches, which are not merged yet but
which are already in use and are likely to be merged soon.

This resurrects a patch sent long ago by Mikkel Hagen <mhagen@iol.unh.edu>.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Arbel and Sinai devices support checksum generation and verification
of TCP and UDP packets for UD IPoIB messages.  This patch checks if
the HCA supports this and sets the IB_DEVICE_UD_IP_CSUM capability
flag if it does.  It implements support for handling the IB_SEND_IP_CSUM
send flag and setting the csum_ok field in receive work completions.
Signed-off-by: NEli Cohen <eli@mellnaox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

We have recently discovered that Tavor mode requires each WQE in a
posted list of receive WQEs to have a valid NDA field at all times.
This requirement holds true for regular QPs as well as for SRQs.  This
patch prelinks the receive queue in a regular QP and keeps the free
list in SRQ always properly linked.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Reviewed-by: NJack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Architectures such as ia64 see alignment traps when doing a 64-bit 
read from __be32 doorbell[2] arrays to do doorbell writes in 
mthca_write64().  Fix this by just passing the two halves of the 
doorbell value into mthca_write64().  This actually improves the 
generated code by allowing the compiler to see what's going on better.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

    
Current code sets size0 to 0 at the start of work request posting
functions and then handles size0 == 0 specially within the loop over
work requests.  Change this so size0 is set along with f0 the first
time through the loop (when nreq == 0).  This makes the code easier to
understand by making it clearer that f0 and size0 are always
initialized if nreq != 0 without having to know that size0 == 0
implies nreq == 0.

Also annotate size0 with uninitialized_var() so that this doesn't
introduce a new compiler warning.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

    
Factor code to set UD entries out of the work request posting
functions into inline functions set_tavor_ud_seg() and
set_arbel_ud_seg().  This doesn't change the generated code in any
significant way, and makes the source easier on the eyes.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

    
Factor code to set remote address and atomic segment entries out of the
work request posting functions into inline functions set_raddr_seg()
and set_atomic_seg().  This doesn't change the generated code in any
significant way, and makes the source easier on the eyes.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Factor code to set data segment entries out of the work request
posting functions into inline functions mthca_set_data_seg() and
mthca_set_data_seg_inval().  This makes the code more readable and
also allows the compiler to do a better job -- on x86_64:

add/remove: 0/0 grow/shrink: 0/6 up/down: 0/-69 (-69)
function                                     old     new   delta
mthca_arbel_post_srq_recv                    373     369      -4
mthca_arbel_post_receive                     570     562      -8
mthca_tavor_post_srq_recv                    520     508     -12
mthca_tavor_post_send                       1344    1330     -14
mthca_arbel_post_send                       1481    1467     -14
mthca_tavor_post_receive                     792     775     -17
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Commit 9db48926 ("drivers/infiniband/hw/mthca/mthca_qp: kill uninit'd
var warning") added "= 0" to the declarations of f0 to shut up gcc
warnings.  However, there's no point in making the code bigger by
initializing f0 to a random value just to get rid of a warning;
setting f0 to 0 is no safer than just using uninitialized_var(), which
documents the situation better and gives smaller code too.  For example, 
on x86_64:

add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-16 (-16)
function                                     old     new   delta
mthca_tavor_post_send                       1352    1344      -8
mthca_arbel_post_send                       1489    1481      -8
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/mthca/mthca_qp.c: In function
  ‘mthca_tavor_post_send’:
drivers/infiniband/hw/mthca/mthca_qp.c:1594: warning: ‘f0’ may be used
  uninitialized in this function
drivers/infiniband/hw/mthca/mthca_qp.c: In function
  ‘mthca_arbel_post_send’:
drivers/infiniband/hw/mthca/mthca_qp.c:1949: warning: ‘f0’ may be used
  uninitialized in this function

Initializing 'f0' is not strictly necessary in either case, AFAICS.

I was considering use of uninitialized_var(), but looking at the
complex flow of control in each function, I feel it is wiser and
safer to simply zero the var and be certain of ourselves.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

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>

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>

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>

Fix posting lists of > 255 receive WRs for Tavor: rq.next_ind must
be updated each doorbell, otherwise the next doorbell will use an
incorrect index.

Found by Ronni Zimmermann at Mellanox.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

With mthca, RC QPs can starve each other and even UD QPs on the same
hardware schedule queue.  As a result, userspace MPI can starve
e.g. IPoIB traffic, with netdev watchdog warnings getting printed out,
and TCP connections getting stuck or failing.

Reduce the chance of this happening by using three separate hardware
schedule queues: one for userspace RC QPs, one for kernel RC QPs, and
one for all other QPs.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

mthca_free_qp() already has local variables to hold the QP's send_cq
and recv_cq, so we can slightly clean up the calls to mthca_cq_clean()
by using those local variables instead of expressions like
to_mcq(qp->ibqp.send_cq).

Also, by cleaning the recv_cq first, we can avoid worrying about
whether the QP is attached to an SRQ for the second call, because we
would only clean send_cq if send_cq is not equal to recv_cq, and that
means send_cq cannot have any receive completions from the QP being
destroyed.

All this work even improves the generated code a bit:

add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-5 (-5)
function                                     old     new   delta
mthca_free_qp                                510     505      -5
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

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: NRoland Dreier <rolandd@cisco.com>

RESET->RESET is an allowed QP state transition, so mthca should handle
it correctly, by just returning success without involving the firmware.
Signed-off-by: NDotan Barak <dotanb@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When clearing the ib_ah_attr parameter in to_ib_ah_attr(), use sizeof
*ib_ah_attr instead of sizeof *path.

Pointed out by Jack Morgenstein <jackm@mellanox.co.il>.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If a QP being queried is in the RESET state, don't execute the
QUERY_QP firmware command (because it will fail).
Signed-off-by: NDotan Barak <dotanb@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This facility provides three entry points:

	ilog2()		Log base 2 of unsigned long
	ilog2_u32()	Log base 2 of u32
	ilog2_u64()	Log base 2 of u64

These facilities can either be used inside functions on dynamic data:

	int do_something(long q)
	{
		...;
		y = ilog2(x)
		...;
	}

Or can be used to statically initialise global variables with constant values:

	unsigned n = ilog2(27);

When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant.  They treat negative numbers as
unsigned.

When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.

[akpm@osdl.org: MMC fix]
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Commit b3b30f5e ("IB/mthca: Recover from catastrophic errors")
introduced some section mismatch breakage, because the error recovery
code tears down and reinitializes the device, which calls into lots of
code originally marked __devinit and __devexit from regular .text.

Fix this by getting rid of these now-incorrect section markers.

Reported by Randy Dunlap <randy.dunlap@oracle.com>.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

We discovered a problem when running IPoIB applications on multiple
CPUs on an Altix system. Many messages such as:

ib_mthca 0002:01:00.0: SQ 000014 full (19941644 head, 19941707 tail, 64 max, 0 nreq)

appear in syslog, and the driver wedges up.

Apparently this is because writes to the doorbells from different CPUs
reach the device out of order. The following patch adds mmiowb() calls
after doorbell rings to ensure the doorbell writes are ordered.
Signed-off-by: NArthur Kepner <akepner@sgi.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If a QP has separate send and receive CQs, then the send CQ will never
have receive completions from that QP in it.  So when cleaning the
send CQ, there's no need to pass in an SRQ pointer, even if the QP is
attached to an SRQ.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Incorrect number of bits was taken for static_rate field.
Signed-off-by: NJack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

port_num was not being returned for unconnected QPs.
Signed-off-by: NJack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Pass a struct ib_udata to the low-level driver's ->modify_srq() and
->modify_qp() methods, so that it can get to the device-specific data
passed in by the userspace driver.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When destroying a QP, mthca locks both the QP's send CQ and receive
CQ.  However, the following scenario is perfectly valid:

    QP_a: send_cq == CQ_x, recv_cq == CQ_y
    QP_b: send_cq == CQ_y, recv_cq == CQ_x

The old mthca code simply locked send_cq and then recv_cq, which in
this case could lead to an AB-BA deadlock if QP_a and QP_b were
destroyed simultaneously.

We can fix this by changing the locking code to lock the CQ with the
lower CQ number first, which will create a consistent lock ordering.
Also, the second CQ is locked with spin_lock_nested() to tell lockdep
that we know what we're doing with the lock nesting.

This bug was found by lockdep.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The fence bit needs to be set in the doorbell too, not just the WQE.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

After recent changes, mthca_wq_init does not actually initialize the WQ as it
used to - it simply resets all index fields to their initial values.  So,
let's rename it to mthca_wq_reset.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Acked-by: NZach Brown <zach.brown@oracle.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

mthca: initialize send and receive queue locks separately

lockdep identifies a lock by the call site of its initialization.  By
initializing the send and receive queue locks in mthca_wq_init() we confuse
lockdep.  It warns that that the ordered acquiry of both locks in
mthca_modify_qp() is recursive acquiry of one lock:

  =============================================
  [ INFO: possible recursive locking detected ]
  ---------------------------------------------
  modprobe/1192 is trying to acquire lock:
   (&wq->lock){....}, at: [<f892b4db>] mthca_modify_qp+0x60/0xa7b [ib_mthca]
  but task is already holding lock:
   (&wq->lock){....}, at: [<f892b4ce>] mthca_modify_qp+0x53/0xa7b [ib_mthca]

Initializing the locks separately in mthca_alloc_qp_common() stops the
warning and will let lockdep enforce proper ordering on paths that acquire
both locks.
Signed-off-by: NZach Brown <zach.brown@oracle.com>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Documentation/infiniband/core_locking.txt says:

  All of the methods in struct ib_device exported by a low-level
  driver must be fully reentrant.  The low-level driver is required to
  perform all synchronization necessary to maintain consistency, even
  if multiple function calls using the same object are run
  simultaneously.

However, mthca's modify_qp, modify_srq and resize_cq methods are
currently not reentrant.  Add a mutex to the QP, SRQ and CQ structures
so that these calls can be properly serialized.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Some error paths after the mthca_alloc_mailbox() call in mthca_modify_qp()
just do a "return -EINVAL" without freeing the mailbox.  Convert these
returns to "goto out" to avoid leaking the mailbox storage.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If we post a list of length 256 exactly, nreq in doorbell gets set to
256 which is wrong: it should be encoded by 0.  This is because we
only zero it out on the next WR, which may not be there.  The solution
is to ring the doorbell after posting a WQE, not before posting the
next one.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>