Commit Graph

26 Commits

Author SHA1 Message Date
Chuck Lever b024dd0eba rxe: IB_WR_REG_MR does not capture MR's iova field
FRWR memory registration is done with a series of calls and WRs.
1. ULP invokes ib_dma_map_sg()
2. ULP invokes ib_map_mr_sg()
3. ULP posts an IB_WR_REG_MR on the Send queue

Step 2 generates an iova. It is permissible for ULPs to change this
iova (with certain restrictions) between steps 2 and 3.

rxe_map_mr_sg captures the MR's iova but later when rxe processes the
REG_MR WR, it ignores the MR's iova field. If a ULP alters the MR's iova
after step 2 but before step 3, rxe never captures that change.

When the remote sends an RDMA Read targeting that MR, rxe looks up the
R_key, but the altered iova does not match the iova stored in the MR,
causing the RDMA Read request to fail.

Reported-by: Anna Schumaker <schumaker.anna@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-11-29 17:10:06 -07:00
Zhu Yanjun a854b1e890 IB/rxe: move the variable into the function that uses it
The variable rxe is only used in the function rxe_xmit_packet, and the
caller functions do not use it. So move this variable into the function
rxe_xmit_packet.

Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-11-08 14:22:54 -07:00
Vijay Immanuel 030e46e495 IB/rxe: fixes for rdma read retry
When a read request is retried for the remaining partial
data, the response may restart from read response first
or read response only. So support those cases.

Do not advance the comp psn beyond the current wqe's last_psn
as that could skip over an entire read wqe and will cause the
req_retry() logic to set an incorrect req psn.
An example sequence is as follows:
Write        PSN 40 -- this is the current WQE.
Read request PSN 41
Write        PSN 42
Receive ACK  PSN 42 -- this will complete the current WQE
for PSN 40, and set the comp psn to 42 which is a problem
because the read request at PSN 41 has been skipped over.
So when req_retry() tries to retransmit the read request,
it sets the req psn to 42 which is incorrect.

When retrying a read request, calculate the number of psns
completed based on the dma resid instead of the wqe first_psn.
The wqe first_psn could have moved if the read request was
retried multiple times.

Set the reth length to the dma resid to handle read retries for
the remaining partial data.

Signed-off-by: Vijay Immanuel <vijayi@attalasystems.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-08-30 17:27:15 -04:00
Parav Pandit 3db2bceb29 IB/rxe: Simplify rxe_find_route() to avoid GID query for netdev
rxe_prepare() is called on an skb which has ndev already initialized by
rxe_init_packet().
Therefore avoid querying the GID attribute again and use the available
netdevice from the skb->dev.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Tested-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-08-30 16:31:50 -04:00
Vijay Immanuel 375dc53d03 IB/rxe: Fix missing completion for mem_reg work requests
Run the completer task to post a work completion after processing
a memory registration or invalidate work request. This covers the
case where the memory registration or invalidate was the last work
request posted to the qp.

Signed-off-by: Vijay Immanuel <vijayi@attalasystems.com>
Reviewed-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-06-18 11:36:13 -06:00
Zhu Yanjun 828d810550 IB/rxe: avoid double kfree skb
In rxe_send, when network_type is not RDMA_NETWORK_IPV4 or
RDMA_NETWORK_IPV6, skb is freed and -EINVAL is returned.
Then rxe_xmit_packet will return -EINVAL, too. In rxe_requester,
this skb is double freed.
In rxe_requester, kfree_skb is needed only after fill_packet fails.
So kfree_skb is moved from label err to test fill_packet.

Fixes: 5793b46521 ("IB/rxe: remove unnecessary skb_clone in xmit")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-06-11 11:02:27 -06:00
Doug Ledford f5e27a203f Merge branch 'k.o/for-rc' into k.o/wip/dl-for-next
Several items of conflict have arisen between the RDMA stack's for-rc
branch and upcoming for-next work:

9fd4350ba8 ("IB/rxe: avoid double kfree_skb") directly conflicts with
2e47350789 ("IB/rxe: optimize the function duplicate_request")

Patches already submitted by Intel for the hfi1 driver will fail to
apply cleanly without this merge

Other people on the mailing list have notified that their upcoming
patches also fail to apply cleanly without this merge

Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-05-09 15:48:48 -04:00
Zhu Yanjun 9fd4350ba8 IB/rxe: avoid double kfree_skb
When skb is sent, it will pass the following functions in soft roce.

rxe_send [rdma_rxe]
    ip_local_out
        __ip_local_out
        ip_output
            ip_finish_output
                ip_finish_output2
                    dev_queue_xmit
                        __dev_queue_xmit
                            dev_hard_start_xmit

In the above functions, if error occurs in the above functions or
iptables rules drop skb after ip_local_out, kfree_skb will be called.
So it is not necessary to call kfree_skb in soft roce module again.
Or else crash will occur.

The steps to reproduce:

     server                       client
    ---------                    ---------
    |1.1.1.1|<----rxe-channel--->|1.1.1.2|
    ---------                    ---------

On server: rping -s -a 1.1.1.1 -v -C 10000 -S 512
On client: rping -c -a 1.1.1.1 -v -C 10000 -S 512

The kernel configs CONFIG_DEBUG_KMEMLEAK and
CONFIG_DEBUG_OBJECTS are enabled on both server and client.

When rping runs, run the following command in server:

iptables -I OUTPUT -p udp  --dport 4791 -j DROP

Without this patch, crash will occur.

CC: Srinivas Eeda <srinivas.eeda@oracle.com>
CC: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-04-27 14:20:47 -04:00
Zhu Yanjun e12ee8ce51 IB/rxe: remove unused function variable
In the functions rxe_mem_init_dma, rxe_mem_init_user, rxe_mem_init_fast
and copy_data, the function variable rxe is not used. So this function
variable rxe is removed.

CC: Srinivas Eeda <srinivas.eeda@oracle.com>
CC: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-04-27 12:18:29 -04:00
Bart Van Assche 65567e4121 RDMA/rxe: Fix a race condition in rxe_requester()
The rxe driver works as follows:
* The send queue, receive queue and completion queues are implemented as
  circular buffers.
* ib_post_send() and ib_post_recv() calls are serialized through a spinlock.
* Removing elements from various queues happens from tasklet
  context. Tasklets are guaranteed to run on at most one CPU. This serializes
  access to these queues. See also rxe_completer(), rxe_requester() and
  rxe_responder().
* rxe_completer() processes the skbs queued onto qp->resp_pkts.
* rxe_requester() handles the send queue (qp->sq.queue).
* rxe_responder() processes the skbs queued onto qp->req_pkts.

Since rxe_drain_req_pkts() processes qp->req_pkts, calling
rxe_drain_req_pkts() from rxe_requester() is racy. Hence this patch.

Reported-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-01-18 14:49:19 -05:00
Kees Cook 3bfbea7473 IB/rxe: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Moni Shoua <monis@mellanox.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-10-25 15:24:49 -04:00
Andrew Boyer 1223a1af75 IB/rxe: Another fix for broken receive queue draining
This fixes another path in rxe_requester() that might overlook stale SKBs,
preventing cleanup.

Fixes: 1217197142 ("rxe: fix broken receive queue draining")
Signed-off-by: Andrew Boyer <andrew.boyer@dell.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-28 19:12:35 -04:00
Kamal Heib c498e82e3c IB/rxe: Prefer 'unsigned int' to bare use of 'unsigned'
Signed-off-by: Kamal Heib <kamalh@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-07-24 08:43:12 -04:00
yonatanc cee2688e3c IB/rxe: Offload CRC calculation when possible
Use CPU ability to perform CRC calculations, by
replacing direct calls to crc32_le() with crypto_shash_updata().

The overall performance gain measured with ib_send_bw tool is 10% and it
was tested on "Intel CPU ES-2660 v2 @ 2.20Ghz" CPU.

ib_send_bw -d rxe0  -x 1 -n 9000 -e  -s $((1024 * 1024 )) -l 100

---------------------------------------------------------------------------------------------
|             | bytes   | iterations | BW peak[MB/sec] | BW average[MB/sec] | MsgRate[Mpps] |
---------------------------------------------------------------------------------------------
| crc32_le    | 1048576 | 9000       | inf             | 497.60             | 0.000498      |
| CRC offload | 1048576 | 9000       | inf             | 546.70             | 0.000547      |
---------------------------------------------------------------------------------------------

Fixes: 8700e3e7c4 ("Soft RoCE driver")
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-04-21 10:45:02 -04:00
Dan Carpenter ded2602353 IB/rxe: double free on error
"goto err;" has it's own kfree_skb() call so it's a double free.  We
only need to free on the "goto exit;" path.

Fixes: 8700e3e7c4 ("Soft RoCE driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-03-24 20:53:32 -04:00
Bart Van Assche 839f5ac0d8 IB/rxe: Remove a pointless indirection layer
Neither rxe->ifc_ops nor any of the function pointers in struct
struct rxe_ifc_ops ever change. Hence remove the rxe->ifc_ops
indirection mechanism.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Andrew Boyer <andrew.boyer@dell.com>
Cc: Moni Shoua <monis@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-01-10 16:52:47 -05:00
Bart Van Assche ab17654476 IB/rxe: Fix reference leaks in memory key invalidation code
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Andrew Boyer <andrew.boyer@dell.com>
Cc: Moni Shoua <monis@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-01-10 16:52:47 -05:00
Bart Van Assche 18d3451c0d IB/rxe: Generate a completion for all failed work requests
Change do_complete() such that an error completion is not only
generated if a QP is in the error state but also if a work request
failed.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Andrew Boyer <andrew.boyer@dell.com>
Cc: Moni Shoua <monis@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-01-10 16:52:47 -05:00
Bart Van Assche 175f1244c1 IB/rxe: Remove an unused variable and an unused argument
The variable 'av' is not used so remove it. Since that change
removes the last user of the 'wqe' argument, remove that argument
too.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Andrew Boyer <andrew.boyer@dell.com>
Cc: Moni Shoua <monis@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-01-10 16:52:47 -05:00
Linus Torvalds 4d5b57e05a Updates for 4.10 kernel merge window
- Shared mlx5 updates with net stack (will drop out on merge if Dave's
   tree has already been merged)
 - Driver updates: cxgb4, hfi1, hns-roce, i40iw, mlx4, mlx5, qedr, rxe
 - Debug cleanups
 - New connection rejection helpers
 - SRP updates
 - Various misc fixes
 - New paravirt driver from vmware
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma

Pull rdma updates from Doug Ledford:
 "This is the complete update for the rdma stack for this release cycle.

  Most of it is typical driver and core updates, but there is the
  entirely new VMWare pvrdma driver. You may have noticed that there
  were changes in DaveM's pull request to the bnxt Ethernet driver to
  support a RoCE RDMA driver. The bnxt_re driver was tentatively set to
  be pulled in this release cycle, but it simply wasn't ready in time
  and was dropped (a few review comments still to address, and some
  multi-arch build issues like prefetch() not working across all
  arches).

  Summary:

   - shared mlx5 updates with net stack (will drop out on merge if
     Dave's tree has already been merged)

   - driver updates: cxgb4, hfi1, hns-roce, i40iw, mlx4, mlx5, qedr, rxe

   - debug cleanups

   - new connection rejection helpers

   - SRP updates

   - various misc fixes

   - new paravirt driver from vmware"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (210 commits)
  IB: Add vmw_pvrdma driver
  IB/mlx4: fix improper return value
  IB/ocrdma: fix bad initialization
  infiniband: nes: return value of skb_linearize should be handled
  MAINTAINERS: Update Intel RDMA RNIC driver maintainers
  MAINTAINERS: Remove Mitesh Ahuja from emulex maintainers
  IB/core: fix unmap_sg argument
  qede: fix general protection fault may occur on probe
  IB/mthca: Replace pci_pool_alloc by pci_pool_zalloc
  mlx5, calc_sq_size(): Make a debug message more informative
  mlx5: Remove a set-but-not-used variable
  mlx5: Use { } instead of { 0 } to init struct
  IB/srp: Make writing the add_target sysfs attr interruptible
  IB/srp: Make mapping failures easier to debug
  IB/srp: Make login failures easier to debug
  IB/srp: Introduce a local variable in srp_add_one()
  IB/srp: Fix CONFIG_DYNAMIC_DEBUG=n build
  IB/multicast: Check ib_find_pkey() return value
  IPoIB: Avoid reading an uninitialized member variable
  IB/mad: Fix an array index check
  ...
2016-12-15 12:03:32 -08:00
Andrew Boyer 37f69f43fb IB/rxe: Hold refs when running tasklets
It might be possible for all of a QP's references to be dropped
while one of that QP's tasklets is running.

For example, the completer might run during QP destroy.
If qp->valid is false, it will drop all of the packets on
the resp_pkts list, potentially removing the last reference.
Then it tries to advance the SQ consumer pointer. If the
SQ's buffer has already been destroyed, the system will
panic.

To be safe, hold a reference on the QP for the duration
of each tasklet.

Signed-off-by: Andrew Boyer <andrew.boyer@dell.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-12-12 16:34:22 -05:00
Arnd Bergmann a0fa72683e IB/rxe: avoid putting a large struct rxe_qp on stack
A race condition fix added an rxe_qp structure to the stack in order
to be able to perform rollback in rxe_requester(), but the structure
is large enough to trigger the warning for possible stack overflow:

drivers/infiniband/sw/rxe/rxe_req.c: In function 'rxe_requester':
drivers/infiniband/sw/rxe/rxe_req.c:757:1: error: the frame size of 2064 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

This changes the rollback function to only save the psn inside
the qp, which is the only field we access in the rollback_qp
anyway.

Fixes: 3050b99850 ("IB/rxe: Fix race condition between requester and completer")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-12-12 16:31:45 -05:00
Yonatan Cohen 002e062e13 IB/rxe: Fix handling of erroneous WR
To correctly handle a erroneous WR this fix does the following
1. Make sure the bad WQE causes a user completion event.
2. Call rxe_completer to handle the erred WQE.

Before the fix, when rxe_requester found a bad WQE, it changed its
status to IB_WC_LOC_PROT_ERR and exit with 0 for non RC QPs.

If this was the 1st WQE then there would be no ACK to invoke the
completer and this bad WQE would be stuck in the QP's send-q.

On top of that the requester exiting with 0 caused rxe_do_task to
endlessly invoke rxe_requester, resulting in a soft-lockup attached
below.

In case the WQE was not the 1st and rxe_completer did get a chance to
handle the bad WQE, it did not cause a complete event since the WQE's
IB_SEND_SIGNALED flag was not set.

Setting WQE status to IB_SEND_SIGNALED is subject to IBA spec
version 1.2.1, section 10.7.3.1 Signaled Completions.

NMI watchdog: BUG: soft lockup - CPU#7 stuck for 22s!
[<ffffffffa0590145>] ? rxe_pool_get_index+0x35/0xb0 [rdma_rxe]
[<ffffffffa05952ec>] lookup_mem+0x3c/0xc0 [rdma_rxe]
[<ffffffffa0595534>] copy_data+0x1c4/0x230 [rdma_rxe]
[<ffffffffa058c180>] rxe_requester+0x9d0/0x1100 [rdma_rxe]
[<ffffffff8158e98a>] ? kfree_skbmem+0x5a/0x60
[<ffffffffa05962c9>] rxe_do_task+0x89/0xf0 [rdma_rxe]
[<ffffffffa05963e2>] rxe_run_task+0x12/0x30 [rdma_rxe]
[<ffffffffa059110a>] rxe_post_send+0x41a/0x550 [rdma_rxe]
[<ffffffff811ef922>] ? __kmalloc+0x182/0x200
[<ffffffff816ba512>] ? down_read+0x12/0x40
[<ffffffffa054bd32>] ib_uverbs_post_send+0x532/0x540 [ib_uverbs]
[<ffffffff815f8722>] ? tcp_sendmsg+0x402/0xb80
[<ffffffffa05453dc>] ib_uverbs_write+0x18c/0x3f0 [ib_uverbs]
[<ffffffff81623c2e>] ? inet_recvmsg+0x7e/0xb0
[<ffffffff8158764d>] ? sock_recvmsg+0x3d/0x50
[<ffffffff81215b87>] __vfs_write+0x37/0x140
[<ffffffff81216892>] vfs_write+0xb2/0x1b0
[<ffffffff81217ce5>] SyS_write+0x55/0xc0
[<ffffffff816bc672>] entry_SYSCALL_64_fastpath+0x1a/0xa

Fixes: 8700e3e7c4 ("Soft RoCE driver")
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Reviewed-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-11-16 20:03:44 -05:00
Parav Pandit e404f945a6 IB/rxe: improved debug prints & code cleanup
1. Debugging qp state transitions and qp errors in loopback and
multiple QP tests is difficult without qp numbers in debug logs.
This patch adds qp number to important debug logs.

2. Instead of having rxe: prefix in few logs and not having in
few logs, using uniform module name prefix using pr_fmt macro.

3. Code cleanup for various warnings reported by checkpatch for
incomplete unsigned data type, line over 80 characters, return
statements.

Signed-off-by: Parav Pandit <pandit.parav@gmail.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-10-06 13:50:04 -04:00
Yonatan Cohen 3050b99850 IB/rxe: Fix race condition between requester and completer
rxe_requester() is sending a pkt with rxe_xmit_packet() and
then calls rxe_update() to update the wqe and qp's psn values.
But sometimes the response is received before the requester
had time to update the wqe in which case the completer
acts on errornous wqe values.
This fix updates the wqe and qp before actually sending
the request and rolls back when xmit fails.

Fixes: 8700e3e7c4 ("Soft RoCE driver")
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-09-16 14:14:08 -04:00
Moni Shoua 8700e3e7c4 Soft RoCE driver
Soft RoCE (RXE) - The software RoCE driver

ib_rxe implements the RDMA transport and registers to the RDMA core
device as a kernel verbs provider. It also implements the packet IO
layer. On the other hand ib_rxe registers to the Linux netdev stack
as a udp encapsulating protocol, in that case RDMA, for sending and
receiving packets over any Ethernet device.  This yields a RDMA
transport over the UDP/Ethernet network layer forming a RoCEv2
compatible device.

The configuration procedure of the Soft RoCE drivers requires
binding to any existing Ethernet network device. This is done with
/sys interface.

A userspace Soft RoCE library (librxe) provides user applications
the ability to run with Soft RoCE devices.  The use of rxe verbs ins
user space requires the inclusion of librxe as a device specifics
plug-in to libibverbs. librxe is packaged separately.

Architecture:

     +-----------------------------------------------------------+
     |                          Application                      |
     +-----------------------------------------------------------+
                            +-----------------------------------+
                            |             libibverbs            |
User                        +-----------------------------------+
                            +----------------+ +----------------+
                            | librxe         | | HW RoCE lib    |
                            +----------------+ +----------------+
+---------------------------------------------------------------+
     +--------------+                           +------------+
     | Sockets      |                           | RDMA ULP   |
     +--------------+                           +------------+
     +--------------+                  +---------------------+
     | TCP/IP       |                  | ib_core             |
     +--------------+                  +---------------------+
                             +------------+ +----------------+
Kernel                       | ib_rxe     | | HW RoCE driver |
                             +------------+ +----------------+
     +------------------------------------+
     | NIC driver                         |
     +------------------------------------+

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     +-----------------------------------------------------------+
     |                          Application                      |
     +-----------------------------------------------------------+
                            +-----------------------------------+
                            |             libibverbs            |
User                        +-----------------------------------+
                            +----------------+ +----------------+
                            | librxe         | | HW RoCE lib    |
                            +----------------+ +----------------+
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     +--------------+                           +------------+
     | Sockets      |                           | RDMA ULP   |
     +--------------+                           +------------+
     +--------------+                  +---------------------+
     | TCP/IP       |                  | ib_core             |
     +--------------+                  +---------------------+
                             +------------+ +----------------+
Kernel                       | ib_rxe     | | HW RoCE driver |
                             +------------+ +----------------+
     +------------------------------------+
     | NIC driver                         |
     +------------------------------------+
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Soft RoCE resources:

[1[ https://github.com/SoftRoCE/librxe-dev librxe - source code in
Github
[2] https://github.com/SoftRoCE/rxe-dev/wiki/rxe-dev:-Home - Soft RoCE
Wiki page
[3] https://github.com/SoftRoCE/librxe-dev - Soft RoCE userspace library

Signed-off-by: Kamal Heib <kamalh@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-08-04 11:13:12 -04:00