IB: Use capital "OR" for multiple licenses in SPDX

Documentation/process/license-rules.rst and checkpatch expect the SPDX
identifier syntax for multiple licenses to use capital "OR". Correct it
to keep consistent format and avoid copy-paste issues.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230823092912.122674-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>

IB/hfi1: Fix wrong mmu_node used for user SDMA packet after invalidate

The hfi1 user SDMA pinned-page cache will leave a stale cache entry when
the cache-entry's virtual address range is invalidated but that cache
entry is in-use by an outstanding SDMA request.

Subsequent user SDMA requests with buffers in or spanning the virtual
address range of the stale cache entry will result in packets constructed
from the wrong memory, the physical pages pointed to by the stale cache
entry.

To fix this, remove mmu_rb_node cache entries from the mmu_rb_handler
cache independent of the cache entry's refcount. Add 'struct kref
refcount' to struct mmu_rb_node and manage mmu_rb_node lifetime with
kref_get() and kref_put().

mmu_rb_node.refcount makes sdma_mmu_node.refcount redundant. Remove
'atomic_t refcount' from struct sdma_mmu_node and change sdma_mmu_node
code to use mmu_rb_node.refcount.

Move the mmu_rb_handler destructor call after a
wait-for-SDMA-request-completion call so mmu_rb_nodes that need
mmu_rb_handler's workqueue to queue themselves up for destruction from an
interrupt context may do so.

Fixes: f48ad614c100 ("IB/hfi1: Move driver out of staging")
Fixes: 00cbce5cbf88 ("IB/hfi1: Fix bugs with non-PAGE_SIZE-end multi-iovec user SDMA requests")
Link: https://lore.kernel.org/r/168451393605.3700681.13493776139032178861.stgit@awfm-02.cornelisnetworks.com
Reviewed-by: Dean Luick <dean.luick@cornelisnetworks.com>
Signed-off-by: Brendan Cunningham <bcunningham@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/hfi1: Fix bugs with non-PAGE_SIZE-end multi-iovec user SDMA requests

hfi1 user SDMA request processing has two bugs that can cause data
corruption for user SDMA requests that have multiple payload iovecs
where an iovec other than the tail iovec does not run up to the page
boundary for the buffer pointed to by that iovec.a

Here are the specific bugs:
1. user_sdma_txadd() does not use struct user_sdma_iovec->iov.iov_len.
Rather, user_sdma_txadd() will add up to PAGE_SIZE bytes from iovec
to the packet, even if some of those bytes are past
iovec->iov.iov_len and are thus not intended to be in the packet.
2. user_sdma_txadd() and user_sdma_send_pkts() fail to advance to the
next iovec in user_sdma_request->iovs when the current iovec
is not PAGE_SIZE and does not contain enough data to complete the
packet. The transmitted packet will contain the wrong data from the
iovec pages.

This has not been an issue with SDMA packets from hfi1 Verbs or PSM2
because they only produce iovecs that end short of PAGE_SIZE as the tail
iovec of an SDMA request.

Fixing these bugs exposes other bugs with the SDMA pin cache
(struct mmu_rb_handler) that get in way of supporting user SDMA requests
with multiple payload iovecs whose buffers do not end at PAGE_SIZE. So
this commit fixes those issues as well.

Here are the mmu_rb_handler bugs that non-PAGE_SIZE-end multi-iovec
payload user SDMA requests can hit:
1. Overlapping memory ranges in mmu_rb_handler will result in duplicate
pinnings.
2. When extending an existing mmu_rb_handler entry (struct mmu_rb_node),
the mmu_rb code (1) removes the existing entry under a lock, (2)
releases that lock, pins the new pages, (3) then reacquires the lock
to insert the extended mmu_rb_node.

If someone else comes in and inserts an overlapping entry between (2)
and (3), insert in (3) will fail.

The failure path code in this case unpins _all_ pages in either the
original mmu_rb_node or the new mmu_rb_node that was inserted between
(2) and (3).
3. In hfi1_mmu_rb_remove_unless_exact(), mmu_rb_node->refcount is
incremented outside of mmu_rb_handler->lock. As a result, mmu_rb_node
could be evicted by another thread that gets mmu_rb_handler->lock and
checks mmu_rb_node->refcount before mmu_rb_node->refcount is
incremented.
4. Related to #2 above, SDMA request submission failure path does not
check mmu_rb_node->refcount before freeing mmu_rb_node object.

If there are other SDMA requests in progress whose iovecs have
pointers to the now-freed mmu_rb_node(s), those pointers to the
now-freed mmu_rb nodes will be dereferenced when those SDMA requests
complete.

Fixes: 7be85676f1d1 ("IB/hfi1: Don't remove RB entry when not needed.")
Fixes: 7724105686e7 ("IB/hfi1: add driver files")
Signed-off-by: Brendan Cunningham <bcunningham@cornelisnetworks.com>
Signed-off-by: Patrick Kelsey <pat.kelsey@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Link: https://lore.kernel.org/r/168088636445.3027109.10054635277810177889.stgit@252.162.96.66.static.eigbox.net
Signed-off-by: Leon Romanovsky <leon@kernel.org>

IB/hfi1: Fix sdma.h tx->num_descs off-by-one errors

Fix three sources of error involving struct sdma_txreq.num_descs.

When _extend_sdma_tx_descs() extends the descriptor array, it uses the
value of tx->num_descs to determine how many existing entries from the
tx's original, internal descriptor array to copy to the newly allocated
one. As this value was incremented before the call, the copy loop will
access one entry past the internal descriptor array, copying its contents
into the corresponding slot in the new array.

If the call to _extend_sdma_tx_descs() fails, _pad_smda_tx_descs() then
invokes __sdma_tx_clean() which uses the value of tx->num_desc to drive a
loop that unmaps all descriptor entries in use. As this value was
incremented before the call, the unmap loop will invoke sdma_unmap_desc()
on a descriptor entry whose contents consist of whatever random data was
copied into it during (1), leading to cascading further calls into the
kernel and driver using arbitrary data.

_sdma_close_tx() was using tx->num_descs instead of tx->num_descs - 1.

Fix all of the above by:
- Only increment .num_descs after .descp is extended.
- Use .num_descs - 1 instead of .num_descs for last .descp entry.

Fixes: f4d26d81ad7f ("staging/rdma/hfi1: Add coalescing support for SDMA TX descriptors")
Link: https://lore.kernel.org/r/167656658879.2223096.10026561343022570690.stgit@awfm-02.cornelisnetworks.com
Signed-off-by: Brendan Cunningham <bcunningham@cornelisnetworks.com>
Signed-off-by: Patrick Kelsey <pat.kelsey@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/hfi1: Convert to SPDX identifier

use SPDX-License-Identifier instead of a verbose license text

Link: https://lore.kernel.org/r/20210823042622.109-1-caihuoqing@baidu.com
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/hfi1: Remove unused function

Remove the unused function sdma_iowait_schedule().

Fixes: 7724105686e7 ("IB/hfi1: add driver files")
Link: https://lore.kernel.org/r/1617026791-89997-1-git-send-email-dennis.dalessandro@cornelisnetworks.com
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Link: https://lore.kernel.org/r/20200213010425.GA13068@embeddedor.com
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> # added a few more

IB/hfi1: Reduce lock contention on iowait_lock for sdma and pio

Commit 4e045572e2c2 ("IB/hfi1: Add unique txwait_lock for txreq events")
laid the ground work to support per resource waiting locking.

This patch adds that with a lock unique to each sdma engine and pio
sendcontext and makes necessary changes for verbs, PSM, and vnic to use
the new locks.

This is particularly beneficial for smaller messages that will exhaust
resources at a faster rate.

Fixes: 7724105686e7 ("IB/hfi1: add driver files")
Reviewed-by: Gary Leshner <Gary.S.Leshner@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/hfi1: Prepare resource waits for dual leg

Current implementation allows each qp to have only one send engine. As
such, each qp has only one list to queue prebuilt packets when send engine
resources are not available. To improve performance, it is desired to
support multiple send engines for each qp.

This patch creates the framework to support two send engines
(two legs) for each qp for the TID RDMA protocol, which can be easily
extended to support more send engines. It achieves the goal by creating a
leg specific struct, iowait_work in the iowait struct, to hold the
work_struct and the tx_list as well as a pointer to the parent iowait
struct.

The hfi1_pkt_state now has an additional field to record the current legs
work structure and that is now passed to all egress waiters to determine
the leg that needs to wait via a new iowait helper. The APIs are adjusted
to use the new leg specific struct as required.

Many new and modified helpers are added to support this change.

Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/hfi1: Right size user_sdma sequence numbers and related variables

Hardware limits the maximum number of packets to u16 packets.

Match that size for all relevant sequence numbers in the user_sdma
engine.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/hfi1: Make the MSIx resource allocation a bit more flexible

The current method of allocating MSIx resources is a bit cumbersome,
and not very easily added to.

Refactor and re-order the code paths into a more consistent interface.

Update the interface so that allocations are not order dependent.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Sadanand Warrier <sadanand.warrier@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Remove duplicated defines

TXREQ defines are duplicated, incompletely, in the sdma header file.

Remove duplicate defines.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Fix for early release of sdma context

With IRQF_SHARED flag set and CONFIG_DEBUG_SHIRQ enabled
module removal may result in panic in sdma_interrupt() routine
if associated sdma context was released before pci_free_irq();

[ 9198.939885] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 9198.940514] IP: sdma_make_progress+0xa5/0x450 [hfi1]
[ 9198.941114] PGD 170bdc0067 P4D 170bdc0067 PUD 172063e067 PMD 0
[ 9198.941783] Oops: 0000 [#1] SMP
.....
[ 9198.958877] CPU: 132 PID: 64173 Comm: rmmod Tainted: G OE 4.14.0-rc4+ #1
[ 9198.961032] Hardware name: Intel Corporation S7200AP/S7200AP, BIOS S72C610.86B.01.02.0118.080620171935 08/06/2017
[ 9198.963323] task: ffff9681397f0000 task.stack: ffffae1647c40000
[ 9198.965695] RIP: 0010:sdma_make_progress+0xa5/0x450 [hfi1]
[ 9198.968082] RSP: 0018:ffffae1647c43be8 EFLAGS: 00010046
[ 9198.970503] RAX: 0000000000000000 RBX: ffff9680ce8b5ca8 RCX: 0000000000000000
[ 9198.973006] RDX: 0000000000000000 RSI: 0000000001a00d28 RDI: ffff9680ce8b5ca0
[ 9198.975546] RBP: ffffae1647c43c40 R08: ffff96814325ec00 R09: 00000000ffffffff
[ 9198.978142] R10: 000000004325e501 R11: ffff96814325ec00 R12: ffff9680ce8b5c44
[ 9198.980779] R13: ffff9680ce8b5ca0 R14: 0000000000000000 R15: ffff9680ce8b5b00
[ 9198.983462] FS: 00007f31196ba740(0000) GS:ffff96819df00000(0000) knlGS:0000000000000000
[ 9198.986231] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9198.989036] CR2: 0000000000000000 CR3: 000000170833f000 CR4: 00000000001406e0
[ 9198.991911] Call Trace:
[ 9198.994847] sdma_engine_interrupt+0x82/0x100 [hfi1]
[ 9198.997852] sdma_interrupt+0x61/0xc0 [hfi1]
[ 9199.000852] __free_irq+0x1b3/0x2d0
[ 9199.003873] free_irq+0x35/0x70
[ 9199.006909] pci_free_irq+0x1c/0x30
[ 9199.009999] clean_up_interrupts+0x53/0xf0 [hfi1]
[ 9199.013137] hfi1_start_cleanup+0x117/0x190 [hfi1]
[ 9199.016315] postinit_cleanup+0x1d/0x270 [hfi1]
[ 9199.019529] remove_one+0x1f3/0x210 [hfi1]
[ 9199.022738] pci_device_remove+0x39/0xc0
[ 9199.025974] device_release_driver_internal+0x141/0x210
[ 9199.029268] driver_detach+0x3f/0x80
[ 9199.032580] bus_remove_driver+0x55/0xd0
[ 9199.035931] driver_unregister+0x2c/0x50
[ 9199.039321] pci_unregister_driver+0x2a/0xa0
[ 9199.042755] hfi1_mod_cleanup+0x10/0xb50 [hfi1]
[ 9199.046196] SyS_delete_module+0x171/0x250
...

Fix by exporting sdma_clean() and removing from sdma_exit().
sdma_exit() now just manipulates the engine state,
leaving the memory free to sdma_clean() which is now called
just before the dd is freed.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Michael J Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Alex Estrin <alex.estrin@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()

Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

IB/hfi1: Serve the most starved iowait entry first

When an egress resource(SDMA descriptors, pio credits) is not available,
a sending thread will be put on the resource's wait queue. When the
resource becomes available again, up to a fixed number of sending threads
can be awakened sequentially and removed from the wait queue, depending
on the number of waiting threads and the number of free resources. Since
each awakened sending thread will send as many packets as possible, it
is highly likely that the first sending thread will consume all the
egress resources. Subsequently, it will be put back to the end of the wait
queue. Depending on the timing when the later sending threads wake up,
they may not be able to send any packet and be again put back to the end
of the wait queue sequentially, right behind the first sending thread.
This starvation cycle continues until some sending threads exceed their
retry limit and consequently fail.

This patch fixes the issue by two simple approaches:
(1) Any starved sending thread will be put to the head of the wait queue
while a served sending thread will be put to the tail;
(2) The most starved sending thread will be served first.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi: Fix up comments in engine mapping

Fix off by 1 error in comments documenting the sdma and send context
mappings.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Inline sdma_txclean() for verbs pio

Short circuit sdma_txclean() by adding an __sdma_txclean()
that is only called when the tx has sdma mappings.

Convert internal calls to __sdma_txclean().

This removes a call from the critical path.

Reviewed-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Add new debugfs sdma_cpu_list file

Add a debugfs sdma_cpu_list file that can be used to examine the CPU to
sdma engine assignments for the whole device.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Reviewed-by: Jianxin Xiong <jianxin.xiong@intel.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Add sysfs interface for affinity setup

Some users want more control over which cpu cores are being used by the
driver. For example, users might want to restrict the driver to some
specified subset of the cores so that they can appropriately partition
processes, irq handlers, and work threads.
To allow the user to fine tune system affinity settings new sysfs
attributes are introduced per sdma engine. This patch adds a new
attribute type for sdma engine and a new cpu_list attribute.
When the user writes a cpu range to the cpu_list attribute the driver
will create an internal cpu->sdma map, which will be used later as a
look-up table to choose an optimal engine for a user requests.

Reviewed-by: Dean Luick <dean.luick@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Reviewed-by: Jianxin Xiong <jianxin.xiong@intel.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Fix the count of user packets submitted to an SDMA engine

Each user SDMA request coming into the driver may contain multiple packets.
Each user packet may use multiple SDMA descriptors to fill the send buffer.
The field seqsubmitted in struct user_sdma_request counts the number of
user packets submitted to an SDMA engine. Sometimes, the intermediate count
may not be updated properly. However, once all the packets' descriptors
are successfully submitted to the SDMA engine, the final count is updated
correctly. But, if only some of the packets are submitted to the engine due
to an error, the intermediate count doesn't reflect the partial number of
packets submitted to the SDMA engine. This can cause a hang later in the
code as the count of packets submitted to the SDMA engine doesn't match the
the count of packets processed by the SDMA engine.

Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Move driver out of staging

The TODO list for the hfi1 driver was completed during 4.6. In addition
other objections raised (which are far beyond what was in the TODO list)
have been addressed as well. It is now time to remove the driver from
staging and into the drivers/infiniband sub-tree.

Reviewed-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>