The create_flow/destroy_flow uverbs and the associated extensions to
the user-kernel verbs ABI are under review and are too experimental to
freeze at this point.

So userspace is not exposed to experimental features and an uinstable
ABI, temporarily disable this for v3.12 (with a Kconfig option behind
staging to reenable it if desired).

The feature will be enabled after proper cleanup for v3.13.

Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Link: http://marc.info/?i=cover.1381351016.git.ydroneaud@opteya.com
Link: http://marc.info/?i=cover.1381177342.git.ydroneaud@opteya.com

[ Add a Kconfig option to reenable these verbs.  - Roland ]

Signed-off-by: Roland Dreier <roland@purestorage.com>

Pull main batch of InfiniBand/RDMA changes from Roland Dreier:
 - Large ocrdma HW driver update: add "fast register" work requests,
   fixes, cleanups
 - Add receive flow steering support for raw QPs
 - Fix IPoIB neighbour race that leads to crash
 - iSER updates including support for using "fast register" memory
   registration
 - IPv6 support for iWARP
 - XRC transport fixes

* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (54 commits)
  RDMA/ocrdma: Fix compiler warning about int/pointer size mismatch
  IB/iser: Fix redundant pointer check in dealloc flow
  IB/iser: Fix possible memory leak in iser_create_frwr_pool()
  IB/qib: Move COUNTER_MASK definition within qib_mad.h header guards
  RDMA/ocrdma: Fix passing wrong opcode to modify_srq
  RDMA/ocrdma: Fill PVID in UMC case
  RDMA/ocrdma: Add ABI versioning support
  RDMA/ocrdma: Consider multiple SGES in case of DPP
  RDMA/ocrdma: Fix for displaying proper link speed
  RDMA/ocrdma: Increase STAG array size
  RDMA/ocrdma: Dont use PD 0 for userpace CQ DB
  RDMA/ocrdma: FRMA code cleanup
  RDMA/ocrdma: For ERX2 irrespective of Qid, num_posted offset is 24
  RDMA/ocrdma: Fix to work with even a single MSI-X vector
  RDMA/ocrdma: Remove the MTU check based on Ethernet MTU
  RDMA/ocrdma: Add support for fast register work requests (FRWR)
  RDMA/ocrdma: Create IRD queue fix
  IB/core: Better checking of userspace values for receive flow steering
  IB/mlx4: Add receive flow steering support
  IB/core: Export ib_create/destroy_flow through uverbs
  ...

Pull PTR_RET() removal patches from Rusty Russell:
 "PTR_RET() is a weird name, and led to some confusing usage.  We ended
  up with PTR_ERR_OR_ZERO(), and replacing or fixing all the usages.

  This has been sitting in linux-next for a whole cycle"

[ There are still some PTR_RET users scattered about, with some of them
  possibly being new, but most of them existing in Rusty's tree too.  We
  have that

      #define PTR_RET(p) PTR_ERR_OR_ZERO(p)

  thing in <linux/err.h>, so they continue to work for now  - Linus ]

* tag 'PTR_RET-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  GFS2: Replace PTR_RET with PTR_ERR_OR_ZERO
  Btrfs: volume: Replace PTR_RET with PTR_ERR_OR_ZERO
  drm/cma: Replace PTR_RET with PTR_ERR_OR_ZERO
  sh_veu: Replace PTR_RET with PTR_ERR_OR_ZERO
  dma-buf: Replace PTR_RET with PTR_ERR_OR_ZERO
  drivers/rtc: Replace PTR_RET with PTR_ERR_OR_ZERO
  mm/oom_kill: remove weird use of ERR_PTR()/PTR_ERR().
  staging/zcache: don't use PTR_RET().
  remoteproc: don't use PTR_RET().
  pinctrl: don't use PTR_RET().
  acpi: Replace weird use of PTR_RET.
  s390: Replace weird use of PTR_RET.
  PTR_RET is now PTR_ERR_OR_ZERO(): Replace most.
  PTR_RET is now PTR_ERR_OR_ZERO

  - Don't allow unsupported comp_mask values, user should check
    ibv_query_device to know which features are supported.
  - Add a check in ib_uverbs_create_flow() to verify the size passed
    from the user space.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Implement ib_uverbs_create_flow() and ib_uverbs_destroy_flow() to
support flow steering for user space applications.

Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Add infrastructure to support extended uverbs capabilities in a
forward/backward manner.  Uverbs command opcodes which are based on
the verbs extensions approach should be greater or equal to
IB_USER_VERBS_CMD_THRESHOLD.  They have new header format and
processed a bit differently.

Whenever a specific IB_USER_VERBS_CMD_XXX is extended, which practically means
it needs to have additional arguments, we will be able to add them without creating
a completely new IB_USER_VERBS_CMD_YYY command or bumping the uverbs ABI version.

This patch for itself doesn't provide the whole scheme which is also dependent
on adding a comp_mask field to each extended uverbs command struct.

The new header framework allows for future extension of the CMD arguments
(ib_uverbs_cmd_hdr.in_words, ib_uverbs_cmd_hdr.out_words) for an existing
new command (that is a command that supports the new uverbs command header format
suggested in this patch) w/o bumping ABI version and with maintaining backward
and formward compatibility to new and old libibverbs versions.

In the uverbs command we are passing both uverbs arguments and the provider arguments.
We split the ib_uverbs_cmd_hdr.in_words to ib_uverbs_cmd_hdr.in_words which will now carry only
uverbs input argument struct size and  ib_uverbs_cmd_hdr.provider_in_words that will carry
the provider input argument size. Same goes for the response (the uverbs CMD output argument).

For example take the create_cq call and the mlx4_ib provider:

The uverbs layer gets libibverb's struct ibv_create_cq (named struct ib_uverbs_create_cq
in the kernel), mlx4_ib gets libmlx4's struct mlx4_create_cq (which includes struct
ibv_create_cq and is named struct mlx4_ib_create_cq in the kernel) and
in_words = sizeof(mlx4_create_cq)/4 .

Thus ib_uverbs_cmd_hdr.in_words carry both uverbs plus mlx4_ib input argument sizes,
where uverbs assumes it knows the size of its input argument - struct ibv_create_cq.

Now, if we wish to add a variable to struct ibv_create_cq, we can add a comp_mask field
to the struct which is basically bit field indicating which fields exists in the struct
(as done for the libibverbs API extension), but we need a way to tell what is the total
size of the struct and not assume the struct size is predefined (since we may get different
struct sizes from different user libibverbs versions). So we know at which point the
provider input argument (struct mlx4_create_cq) begins. Same goes for extending the
provider struct mlx4_create_cq. Thus we split the ib_uverbs_cmd_hdr.in_words to
ib_uverbs_cmd_hdr.in_words which will now carry only uverbs input argument struct size and
ib_uverbs_cmd_hdr.provider_in_words that will carry the provider (mlx4_ib) input argument size.

Signed-off-by: Igor Ivanov <Igor.Ivanov@itseez.com>
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

The RDMA stack allows for applications to create IB_QPT_RAW_PACKET
QPs, which receive plain Ethernet packets, specifically packets that
don't carry any QPN to be matched by the receiving side.  Applications
using these QPs must be provided with a method to program some
steering rule with the HW so packets arriving at the local port can be
routed to them.

This patch adds ib_create_flow(), which allow providing a flow
specification for a QP.  When there's a match between the
specification and a received packet, the packet is forwarded to that
QP, in a the same way one uses ib_attach_multicast() for IB UD
multicast handling.

Flow specifications are provided as instances of struct ib_flow_spec_yyy,
which describe L2, L3 and L4 headers.  Currently specs for Ethernet, IPv4,
TCP and UDP are defined.  Flow specs are made of values and masks.

The input to ib_create_flow() is a struct ib_flow_attr, which contains
a few mandatory control elements and optional flow specs.

    struct ib_flow_attr {
            enum ib_flow_attr_type type;
            u16      size;
            u16      priority;
            u32      flags;
            u8       num_of_specs;
            u8       port;
            /* Following are the optional layers according to user request
             * struct ib_flow_spec_yyy
             * struct ib_flow_spec_zzz
             */
    };

As these specs are eventually coming from user space, they are defined and
used in a way which allows adding new spec types without kernel/user ABI
change, just with a little API enhancement which defines the newly added spec.

The flow spec structures are defined with TLV (Type-Length-Value)
entries, which allows calling ib_create_flow() with a list of variable
length of optional specs.

For the actual processing of ib_flow_attr the driver uses the number
of specs and the size mandatory fields along with the TLV nature of
the specs.

Steering rules processing order is according to the domain over which
the rule is set and the rule priority.  All rules set by user space
applicatations fall into the IB_FLOW_DOMAIN_USER domain, other domains
could be used by future IPoIB RFS and Ethetool flow-steering interface
implementation.  Lower numerical value for the priority field means
higher priority.

The returned value from ib_create_flow() is a struct ib_flow, which
contains a database pointer (handle) provided by the HW driver to be
used when calling ib_destroy_flow().

Applications that offload TCP/IP traffic can also be written over IB
UD QPs.  The ib_create_flow() / ib_destroy_flow() API is designed to
support UD QPs too.  A HW driver can set IB_DEVICE_MANAGED_FLOW_STEERING
to denote support for flow steering.

The ib_flow_attr enum type supports usage of flow steering for promiscuous
and sniffer purposes:

    IB_FLOW_ATTR_NORMAL - "regular" rule, steering according to rule specification

    IB_FLOW_ATTR_ALL_DEFAULT - default unicast and multicast rule, receive
        all Ethernet traffic which isn't steered to any QP

    IB_FLOW_ATTR_MC_DEFAULT - same as IB_FLOW_ATTR_ALL_DEFAULT but only for multicast

    IB_FLOW_ATTR_SNIFFER - sniffer rule, receive all port traffic

ALL_DEFAULT and MC_DEFAULT rules options are valid only for Ethernet link type.

Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Added reference counting mechanism for XRC target QPs between
ib_uqp_object and its ib_uxrcd_object.  This prevents closing an XRC
domain that is still attached to a QP.  In addition, add missing code
in ib_uverbs_destroy_srq() to handle ib_uxrcd_object reference
counting correctly when destroying an xsrq.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Fix a potential race when event occurrs on a target XRC QP and in the
middle of reporting that on its shared qps, one of them is destroyed
by user space application.  Also add note for kernel consumers in
ib_verbs.h that they must not destroy the QP from within the handler.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>