RDMA/rxe: Improve newline in printing messages

Previously rxe_{dbg,info,err}() macros are appended built-in newline,
but some users will add redundant newline sometimes. So remove the
built-in newline for these macros.

In terms of rxe_{dbg,info,err}_xxx() macros, because they don't have
built-in newline, append newline when using them.

CC: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Reviewed-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Acked-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Link: https://lore.kernel.org/r/20240109083253.3629967-1-lizhijian@fujitsu.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

RDMA/rxe: Simplify cq->notify code

The flags parameter to the request notify verb is a bitmask. But, rxe
driver treats cq->notify as an int. If someone ever set both the
IB_CQ_SOLICITED and the IB_CQ_NEXT_COMP bits rxe_cq_post could fail to
generate a completion event. This patch treats the notify flags as a bit
mask consistently and can handle the above case correctly.

Link: https://lore.kernel.org/r/20230612162244.20038-1-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Fix rxe_cq_post

A recent patch replaced a tasklet execution of cq->comp_handler by a
direct call. While this made sense it let changes to cq->notify state be
unprotected and assumed that the cq completion machinery and the ulp done
callbacks were reentrant. The result is that in some cases completion
events can be lost. This patch moves the cq->comp_handler call inside of
the spinlock in rxe_cq_post which solves both issues. This is compatible
with the matching code in the request notify verb.

Fixes: 78b26a335310 ("RDMA/rxe: Remove tasklet call from rxe_cq.c")
Link: https://lore.kernel.org/r/20230612155032.17036-1-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Remove tasklet call from rxe_cq.c

Remove the tasklet call in rxe_cq.c and also the is_dying in the
cq struct. There is no reason for the rxe driver to defer the call
to the cq completion handler by scheduling a tasklet. rxe_cq_post()
is not called in a hard irq context.

The rxe driver currently is incorrect because the tasklet call is
made without protecting the cq pointer with a reference from having
the underlying memory freed before the deferred routine is called.
Executing the comp_handler inline fixes this problem.

Fixes: 8700e3e7c485 ("Soft RoCE driver")
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Link: https://lore.kernel.org/r/20230327215643.10410-1-rpearsonhpe@gmail.com
Acked-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

RDMA/rxe: Cleanup error state handling in rxe_comp.c

Cleanup the handling of qp in the error state, reset state and during
rxe_qp_do_cleanup. Make the same as rxe_resp.c

Link: https://lore.kernel.org/r/20230304174533.11296-5-rpearsonhpe@gmail.com
Signed-off-by: Ian Ziemba <ian.ziemba@hpe.com>
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Change rxe_dbg to rxe_dbg_dev

Replace the name rxe_dbg with rxe_dbg_dev which better matches
the remaining rxe_dbg_xxx macros for debug messages with a
rxe device parameter. Reuse the name rxe_dbg for debug messages
which do not have a rxe device parameter.

Link: https://lore.kernel.org/r/20230303221623.8053-3-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Replace pr_xxx by rxe_dbg_xxx in rxe_cq.c

Replace calls to pr_xxx() in rxe_cq.c with rxe_dbg_xxx().

Link: https://lore.kernel.org/r/20221103171013.20659-4-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Convert pr_warn/err to pr_debug in pyverbs

The pyverbs test suite generates a few dmesg traces from intentional error
tests. This patch replaces those messages with pr_debug() calls which
improves the usefullness of the tests.

Link: https://lore.kernel.org/r/20220630190425.2251-3-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Revert changes from irqsave to bh locks

A previous patch replaced all irqsave locks in rxe with bh locks. This
ran into problems because rdmacm has a bad habit of calling rdma verbs
APIs while disabling irqs. This is not allowed during spin_unlock_bh()
causing programs that use rdmacm to fail. This patch reverts the changes
to locks that had this problem or got dragged into the same mess. After
this patch blktests/check -q srp now runs correctly.

Link: https://lore.kernel.org/r/20220215194448.44369-1-rpearsonhpe@gmail.com
Fixes: 21adfa7a3c4e ("RDMA/rxe: Replace irqsave locks with bh locks")
Reported-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Cleanup rxe_pool_entry

Currently three different names are used to describe rxe pool elements.
They are referred to as entries, elems or pelems. This patch chooses one
'elem' and changes the other ones.

Link: https://lore.kernel.org/r/20211103050241.61293-3-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Replace irqsave locks with bh locks

Most of the locks in the rxe driver are _irqsave/restore locks but in fact
there are no interrupt threads that run rxe code or share data with
rxe. There are softirq threads and data sharing so the appropriate lock
type is _bh. This patch replaces all irqsave type locks with bh type
locks.

Link: https://lore.kernel.org/r/20211103050241.61293-2-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Change the is_user member of struct rxe_cq to bool

Make the is_user members of struct rxe_qp/rxe_cq has the same type.

Link: https://lore.kernel.org/r/20210930094813.226888-3-yangx.jy@fujitsu.com
Signed-off-by: Xiao Yang <yangx.jy@fujitsu.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Add memory barriers to kernel queues

Earlier patches added memory barriers to protect user space to kernel
space communications. The user space queues were previously shown to have
occasional memory synchonization errors which were removed by adding
smp_load_acquire, smp_store_release barriers. This patch extends that to
the case where queues are used between kernel space threads.

This patch also extends the queue types to include kernel ULP queues which
access the other end of the queues in kernel verbs calls like poll_cq and
post_send/recv.

Link: https://lore.kernel.org/r/20210914164206.19768-2-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Protext kernel index from user space

In order to prevent user space from modifying the index that belongs to
the kernel for shared queues let the kernel use a local copy of the index
and copy any new values of that index to the shared rxe_queue_bus struct.

This adds more switch statements which decreases the performance of the
queue API. Move the type into the parameter list for these functions so
that the compiler can optimize out the switch statements when the explicit
type is known. Modify all the calls in the driver on performance paths to
pass in the explicit queue type.

Link: https://lore.kernel.org/r/20210527194748.662636-4-rpearsonhpe@gmail.com
Link: https://lore.kernel.org/linux-rdma/20210526165239.GP1002214@@nvidia.com/
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Add a type flag to rxe_queue structs

To create optimal code only want to use smp_load_acquire() and
smp_store_release() for user indices in rxe_queue APIs since kernel
indices are protected by locks which also act as memory barriers. By
adding a type to the queues we can determine which indices need to be
protected.

Link: https://lore.kernel.org/r/20210527194748.662636-2-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Use acquire/release for memory ordering

Change work and completion queues to use smp_load_acquire() and
smp_store_release() to synchronize between driver and users. This commit
goes with a matching series of commits in the rxe user space provider.

Link: https://lore.kernel.org/r/20201210174258.5234-1-rpearson@hpe.com
Signed-off-by: Bob Pearson <rpearson@hpe.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the struct tasklet_struct
pointer to all tasklet callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.

Link: https://lore.kernel.org/r/20200903060637.424458-6-allen.lkml@gmail.com
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/rxe: Add SPDX hdrs to rxe source files

Add SPDX headers to all rxe .c and .h files.

Link: https://lore.kernel.org/r/20200827145439.2273-1-rpearson@hpe.com
Signed-off-by: Bob Pearson <rpearson@hpe.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB: Pass only ib_udata in function prototypes

Now when ib_udata is passed to all the driver's object create/destroy APIs
the ib_udata will carry the ib_ucontext for every user command. There is
no need to also pass the ib_ucontext via the functions prototypes.

Make ib_udata the only argument psssed.

Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/rxe: replace kvfree with vfree

The buf is allocated by vmalloc_user in the function rxe_queue_init.
So it is better to free it by vfree.

Fixes: 8700e3e7c485 ("Soft RoCE driver")
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/rxe: Use structs to describe the uABI instead of opencoding

Open coding pointer math is not acceptable for describing the uABI in
RDMA. Provide structs for all the cases.

The udata is casted to the struct as close to the verbs entry point
as possible for maximum clarity. Function signatures and so forth
are revised to allow for this.

Tested-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/rxe: Get rid of confusing udata parameter to rxe_cq_chk_attr

It isn't used and it couldn't possibly ever be used correctly.

Tested-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/rxe: Disable completion upcalls when a CQ is destroyed

This prevents the stack from accessing userspace objects while they
are being torn down.

One possible sequence of events:
- Userspace program exits
- ib_uverbs_cleanup_ucontext() runs, calling ib_destroy_qp(),
ib_destroy_cq(), etc. and releasing/freeing the UCQ
- The QP still has tasklets running, so it isn't destroyed yet
- The CQ is referenced by the QP, so the CQ isn't destroyed yet
- The UCQ is kfree()'d anyway
- A send work request completes
- rxe_send_complete() calls cq->ibcq.comp_handler()
- ib_uverbs_comp_handler() runs and crashes; the event queue is checked
for is_closed, but it has no way to check the ib_ucq_object before
accessing it

The reference counting on the CQ doesn't protect against this since the CQ
hasn't been destroyed yet.
There's no available interface to deregister the UCQ from the CQ, and it
didn't appear that attempting to add reference counting to the UCQ was
going to be a good way to go since this solution is much simpler.

Fixes: 8700e3e7c485 ("Soft RoCE driver")
Signed-off-by: Andrew Boyer <andrew.boyer@dell.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/rxe: Let the compiler check the type of the cleanup functions

Change the argument type of these functions from void * into
struct rxe_pool_entry *.

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>

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>