The driver counted on the transactional nature of iSCSI login/text
flows and used the same buffer for both the request and the response.
We also went further and did DMA mapping only once, with
DMA_FROM_DEVICE, which violates the DMA mapping API.  Fix that by
using different buffers, one for requests and one for responses, and
use the correct DMA mapping direction for each.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Some kernel components pin user space memory (infiniband and perf) (by
increasing the page count) and account that memory as "mlocked".

The difference between mlocking and pinning is:

A. mlocked pages are marked with PG_mlocked and are exempt from
   swapping. Page migration may move them around though.
   They are kept on a special LRU list.

B. Pinned pages cannot be moved because something needs to
   directly access physical memory. They may not be on any
   LRU list.

I recently saw an mlockalled process where mm->locked_vm became
bigger than the virtual size of the process (!) because some
memory was accounted for twice:

Once when the page was mlocked and once when the Infiniband
layer increased the refcount because it needt to pin the RDMA
memory.

This patch introduces a separate counter for pinned pages and
accounts them seperately.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Cc: Mike Marciniszyn <infinipath@qlogic.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There's no need to set the vlan-related fields in an IBoE send WQE
control segment:

 - the vlan to be used by a UD QP is set in the datagram segment.
 - for GSI (CM) QP, all the headers down to 8021q and MAC are built by
   the software anyway.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

The IBoE port MTU is derived from the corresponding Ethernet netdevice
MTU, which can support jumbo frames of 9K, and hence surely supports
the max IB mtu of 4K.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

QPs need to be moved to error before telling the firwmare to shutdown
the queue.  Otherwise, the application can submit WRs that will never
get fetched by the hardware and never flushed by the driver.
Signed-off-by: NKumar Sanghvi <kumaras@chelsio.com>
Acked-by: NSteve Wise <swsie@opengridcomputing.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Commit 01e7da6b ("RDMA/cxgb4: Make sure flush CQ entries are
collected on connection close") introduced a potential problem where a
CQ's comp_handler can get called simultaneously from different places
in the iw_cxgb4 driver.  This does not comply with
Documentation/infiniband/core_locking.txt, which states that at a
given point of time, there should be only one callback per CQ should
be active.

This problem was reported by Parav Pandit <Parav.Pandit@Emulex.Com>.
Based on discussion between Parav Pandit and Steve Wise, this patch
fixes the above problem by serializing the calls to a CQ's
comp_handler using a spin_lock.
Reported-by: NParav Pandit <Parav.Pandit@Emulex.Com>
Signed-off-by: NKumar Sanghvi <kumaras@chelsio.com>
Acked-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

iw_cxgb3 has a potential problem where a CQ's comp_handler can get
called simultaneously from different places in iw_cxgb3 driver.  This
does not comply with Documentation/infiniband/core_locking.txt, which
states that at a given point of time, there should be only one
callback per CQ should be active.

Such problem was reported by Parav Pandit <Parav.Pandit@Emulex.Com>
for iw_cxgb4 driver.  Based on discussion between Parav Pandit and
Steve Wise, this patch fixes the above problem by serializing the
calls to a CQ's comp_handler using a spin_lock.
Signed-off-by: NKumar Sanghvi <kumaras@chelsio.com>
Acked-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Fix an issue where the link would come up after replugging a cable
even if it has been DISABLED manually.
Signed-off-by: NMitko Haralanov <mitko@qlogic.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Set the extended active speeds based on the hardware configuration.
Signed-off-by: NMarcel Apfelbaum <marcela@dev.mellanox.co.il>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>

[ Move FDR-10 handling into ib_link_query_port().  - Roland ]
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Hold the link state machine until the tuning data is read from the
QSFP EEPROM so correct tuning settings are applied before the state
machine attempts to bring the link up.  Link is also held on cable
unplug in case a different cable is used.
Signed-off-by: NMitko Haralanov <mitko@qlogic.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

This was probably present from initial submission.
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Review of qib_ruc_check_hdr() shows that the s_lock is not required in
the normal case.  The r_lock is held in all cases, and protects the qp
fields that are read.

The s_lock will be needed to around the call to qib_migrate_qp() to
insure that the send engine sees a consistent set of fields.
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

A new field is added to qib_qp called timeout_jiffies. It is
initialized upon create and modify.

The field is now used instead of a computation based on qp->timeout.
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

The heavy weight spinlock in qib_lookup_qpn() is replaced with RCU.
The hash list itself is now accessed via jhash functions instead of mod.

The changes should benefit multiple receive contexts in different
processors by not contending for the lock just to read the hash
structures.

The patch also adds a lookaside_qp (pointer) and a lookaside_qpn in
the context.  The interrupt handler will test the current packet's qpn
against lookaside_qpn if the lookaside_qp pointer is non-NULL.  The
pointer is NULL'ed when the interrupt handler exits.
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

The context init now saves a shift from rcvegrbufs_perchunk
rcvegrbufs_perchunk_shift using ilog2.   A BUG_ON() protects the
power of 2 assumption.
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Store both the encoded and decoded MTU in the QP structure as a minor
optimization for UC/RC receive routines.
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

The memset for zeroing work completions had been unconditional.

This patch removes the memset and moves the zeroing into the work
completion with a more explicit field by field set.  With this patch,
non-ONLY/non-LAST packets will avoid the overhead since they will not
generate a completion.
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

To ease skb->truesize sanitization, its better to be able to localize
all references to skb frags size.

Define accessors : skb_frag_size() to fetch frag size, and
skb_frag_size_{set|add|sub}() to manipulate it.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pages that were mapped using ib_dma_map_page() should be unmapped
using ib_dma_unmap_page().
Signed-off-by: NDotan Barak <dotanb@dev.mellanox.co.il>
Reviewed-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

When creating flushed receive CQEs, set the QPID field in the t4_cqe
to the SQ QID and not the RQ QID.  Otherwise the poll code will not
find the correct QP context.

Signed-off by: Jonathan Lallinger <jonathan@ogc.us>
Signed-off by: Steve Wise <swise@ogc.us>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

At the time when a peer closes the connection, iw_cxgb4 will not send
a cq event if ibqp.uobject exists.  In that case, its possible for a
user application to get blocked in ibv_get_cq_event().

To resolve this, call the cq's comp_handler to unblock any read from
ibv_get_cq_event().  This will trigger userspace to poll the cq and
collect flush status completions for any pending work requests.
Signed-off-by: NKumar Sanghvi <kumaras@chelsio.com>
Acked-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Allow processes that share the same XRC domain to open an existing
shareable QP.  This permits those processes to receive events on the
shared QP and transfer ownership, so that any process may modify the
QP.  The latter allows the creating process to exit, while a remaining
process can still transition it for path migration purposes.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

XRC TGT QPs are shared resources among multiple processes.  Since the
creating process may exit, allow other processes which share the same
XRC domain to open an existing QP.  This allows us to transfer
ownership of an XRC TGT QP to another process.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Support the creation of XRC INI and TGT QPs.  To handle the case where
a CQ or PD is not provided, we allocate them internally with the xrcd.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Allow the user to create XRC SRQs.  This patch is based on a patch
from Jack Morgenstrein <jackm@dev.mellanox.co.il>.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Support creating and destroying XRC domains.  Any sharing of the XRCD
is managed above the low-level driver.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Because an XRC TGT QP can end up being shared among multiple
processes, don't have the ib_cm automatically send a DREQ when the
userspace process that owns the ib_cm_id exits.  Disconnect can be
initiated by the user directly; otherwise, the owner of the XRC INI QP
controls the connection.

Note that as a result of the process exiting, the ib_cm will stop
tracking the XRC connection on the target side.  For the purposes of
disconnecting, this isn't a big deal.  The ib_cm will respond to the
DREQ appropriately.  For other messages, mainly LAP, the CM will
reject the request, since there's no one available to route the
request to.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Allow users to connect XRC QPs through the rdma_cm.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Allow the user to indicate the QP type separately from the port space
when allocating an rdma_cm_id.  With RDMA_PS_IB, there is no longer a
1:1 relationship between the QP type and port space, so we need to
switch on the QP type to select between UD and connected QPs.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Add RDMA_PS_IB.  XRC QP types will use the IB port space when operating
over the RDMA CM.  For the 'IP protocol' field value, we select 0x3F,
which is listed as being for 'any local network'.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

The XRC annex was updated to have XRC behave more like RD. Specifically,
the XRC TGT QPN moves from the local QPN to local EECN field.  Lookup of
SRQN is done using the REQ/REP protocol.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Update the REQ and REP messages to support XRC connection setup
according to the XRC Annex.  Several existing fields must be set to 0 or
1 when connecting XRC QPs, and a reserved field is changed to an
extended transport type.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Allow user space to operate on XRC TGT QPs the same way as other types
of QPs, with one notable exception: since XRC TGT QPs may be shared
among multiple processes, the XRC TGT QP is allowed to exist beyond the
lifetime of the creating process.

The process that creates the QP is allowed to destroy it, but if the
process exits without destroying the QP, then the QP will be left bound
to the lifetime of the XRCD.

TGT QPs are not associated with CQs or a PD.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

XRC INI QPs are similar to send only RC QPs.  Allow user space to create
INI QPs.  Note that INI QPs do not require receive CQs.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

We require additional information to create XRC SRQs than we can
exchange using the existing create SRQ ABI.  Provide an enhanced create
ABI for extended SRQ types.

Based on patches by Jack Morgenstein <jackm@dev.mellanox.co.il>
and Roland Dreier <roland@purestorage.com>
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Allow user space to create XRC domains.  Because XRCDs are expected to
be shared among multiple processes, we use inodes to identify an XRCD.

Based on patches by Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

XRC TGT QPs are intended to be shared among multiple users and
processes.  Allow the destruction of an XRC TGT QP to be done explicitly
through ib_destroy_qp() or when the XRCD is destroyed.

To support destroying an XRC TGT QP, we need to track TGT QPs with the
XRCD.  When the XRCD is destroyed, all tracked XRC TGT QPs are also
cleaned up.

To avoid stale reference issues, if a user is holding a reference on a
TGT QP, we increment a reference count on the QP.  The user releases the
reference by calling ib_release_qp.  This releases any access to the QP
from a user above verbs, but allows the QP to continue to exist until
destroyed by the XRCD.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

XRC ("eXtended reliable connected") is an IB transport that provides
better scalability by allowing senders to specify which shared receive
queue (SRQ) should be used to receive a message, which essentially
allows one transport context (QP connection) to serve multiple
destinations (as long as they share an adapter, of course).

XRC communication is between an initiator (INI) QP and a target (TGT)
QP.  Target QPs are associated with SRQs through an XRCD.  An XRC TGT QP
behaves like a receive-only RD QP.  XRC INI QPs behave similarly to RC
QPs, except that work requests posted to an XRC INI QP must specify the
remote SRQ that is the target of the work request.

We define two new QP types for XRC, to distinguish between INI and TGT
QPs, and update the core layer to support XRC QPs.

This patch is derived from work by Jack Morgenstein
<jackm@dev.mellanox.co.il>
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

XRC ("eXtended reliable connected") is an IB transport that provides
better scalability by allowing senders to specify which shared receive
queue (SRQ) should be used to receive a message, which essentially
allows one transport context (QP connection) to serve multiple
destinations (as long as they share an adapter, of course).

XRC defines SRQs that are specifically used by XRC connections.  Expand
the SRQ code to support XRC SRQs.  An XRC SRQ is currently restricted to
only XRC use according to the IB XRC Annex.

Portions of this patch were derived from work by
Jack Morgenstein <jackm@dev.mellanox.co.il>.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Currently, there is only a single ("basic") type of SRQ, but with XRC
support we will add a second.  Prepare for this by defining an SRQ type
and setting all current users to IB_SRQT_BASIC.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>