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>

RDMA/hfi1: Move user SDMA system memory pinning code to its own file

Move user SDMA system memory page-pinning code from user_sdma.c to
pin_system.c. Put declarations for non-static functions in pinning.h.

System memory pinning is necessary for processing user SDMA requests but
actual steps are invisible to user SDMA request-processing code. Moving
system memory pinning code for user SDMA to its own file makes this
distinction apparent.

These changes have no effect on userspace.

Signed-off-by: Patrick Kelsey <pat.kelsey@cornelisnetworks.com>
Signed-off-by: Brendan Cunningham <bcunningham@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Link: https://lore.kernel.org/r/169271327311.1855761.4736714053318724062.stgit@awfm-02.cornelisnetworks.com
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>

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: Add additional usdma traces

Add traces that were vital in isolating an issue with pq waitlist in
commit fa8dac396863 ("IB/hfi1: Fix another case where pq is left on
waitlist")

Link: https://lore.kernel.org/r/1617026056-50483-8-git-send-email-dennis.dalessandro@cornelisnetworks.com
Reviewed-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/hfi1: Ensure correct mm is used at all times

Two earlier bug fixes have created a security problem in the hfi1
driver. One fix aimed to solve an issue where current->mm was not valid
when closing the hfi1 cdev. It attempted to do this by saving a cached
value of the current->mm pointer at file open time. This is a problem if
another process with access to the FD calls in via write() or ioctl() to
pin pages via the hfi driver. The other fix tried to solve a use after
free by taking a reference on the mm.

To fix this correctly we use the existing cached value of the mm in the
mmu notifier. Now we can check in the insert, evict, etc. routines that
current->mm matched what the notifier was registered for. If not, then
don't allow access. The register of the mmu notifier will save the mm
pointer.

Since in do_exit() the exit_mm() is called before exit_files(), which
would call our close routine a reference is needed on the mm. We rely on
the mmgrab done by the registration of the notifier, whereas before it was
explicit. The mmu notifier deregistration happens when the user context is
torn down, the creation of which triggered the registration.

Also of note is we do not do any explicit work to protect the interval
tree notifier. It doesn't seem that this is going to be needed since we
aren't actually doing anything with current->mm. The interval tree
notifier stuff still has a FIXME noted from a previous commit that will be
addressed in a follow on patch.

Cc: <stable@vger.kernel.org>
Fixes: e0cf75deab81 ("IB/hfi1: Fix mm_struct use after free")
Fixes: 3faa3d9a308e ("IB/hfi1: Make use of mm consistent")
Link: https://lore.kernel.org/r/20201125210112.104301.51331.stgit@awfm-01.aw.intel.com
Suggested-by: Jann Horn <jannh@google.com>
Reported-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/hfi1: Remove unused define

The patch noted in Fixes missed deleting the define it obsoleted.

Fixes: da9de5f8527f ("IB/hfi1: Close PSM sdma_progress sleep window")
Link: https://lore.kernel.org/r/20190715164552.74174.99396.stgit@awfm-01.aw.intel.com
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/hfi1: Close PSM sdma_progress sleep window

The call to sdma_progress() is called outside the wait lock.

In this case, there is a race condition where sdma_progress() can return
false and the sdma_engine can idle. If that happens, there will be no
more sdma interrupts to cause the wakeup and the user_sdma xmit will hang.

Fix by moving the lock to enclose the sdma_progress() call.

Also, delete busycount. The need for this was removed by:
commit bcad29137a97 ("IB/hfi1: Serve the most starved iowait entry first")

Cc: <stable@vger.kernel.org>
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: 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: Remove race conditions in user_sdma send path

Packet queue state is over used to determine SDMA descriptor
availablitity and packet queue request state.

cpu 0 ret = user_sdma_send_pkts(req, pcount);
cpu 0 if (atomic_read(&pq->n_reqs))
cpu 1 IRQ user_sdma_txreq_cb calls pq_update() (state to _INACTIVE)
cpu 0 xchg(&pq->state, SDMA_PKT_Q_ACTIVE);

At this point pq->n_reqs == 0 and pq->state is incorrectly
SDMA_PKT_Q_ACTIVE. The close path will hang waiting for the state
to return to _INACTIVE.

This can also change the state from _DEFERRED to _ACTIVE. However,
this is a mostly benign race.

Remove the racy code path.

Use n_reqs to determine if a packet queue is active or not.

Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
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: Eliminate races in the SDMA send error path

pq_update() can only be called in two places: from the completion
function when the complete (npkts) sequence of packets has been
submitted and processed, or from setup function if a subset of the
packets were submitted (i.e. the error path).

Currently both paths can call pq_update() if an error occurrs. This
race will cause the n_req value to go negative, hanging file_close(),
or cause a crash by freeing the txlist more than once.

Several variables are used to determine SDMA send state. Most of
these are unnecessary, and have code inspectible races between the
setup function and the completion function, in both the send path and
the error path.

The request 'status' value can be set by the setup or by the
completion function. This is code inspectibly racy. Since the status
is not needed in the completion code or by the caller it has been
removed.

The request 'done' value races between usage by the setup and the
completion function. The completion function does not need this.
When the number of processed packets matches npkts, it is done.

The 'has_error' value races between usage of the setup and the
completion function. This can cause incorrect error handling and leave
the n_req in an incorrect value (i.e. negative).

Simplify the code by removing all of the unneeded state checks and
variables.

Clean up iovs node when it is freed.

Eliminate race conditions in the error path:

If all packets are submitted, the completion handler will set the
completion status correctly (ok or aborted).

If all packets are not submitted, the caller must wait until the
submitted packets have completed, and then set the completion status.

These two change eliminate the race condition in the error path.

Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
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: Remove unused variable

The variable extended_psn was not used any more.

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: Convert the macro AHG_HEADER_SET into an inline function

AHG_HEADER_SET macro doesn't conform to the coding standards as it can
affect the control flow. Convert the macro AHG_HEADER_SET into an inline
function ahg_header_set().

Cc: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@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/hif1: Remove static tracing from SDMA hot path

The hfi1_cdbg() macro can be instantiated in the hot path even when it
is not in use. This shows up on perf profiles.

Rework the macros (for SDMA and MMU), to use the trace interface directly
to eliminate this performance hit.

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: Move structure and MACRO definitions in user_sdma.c to user_sdma.h

Clean up user_sdma.c by moving the structure and MACRO definitions into
the header file user_sdma.h

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@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: Only set fd pointer when base context is completely initialized

The allocate_ctxt() function adds the context to the fd data structure.
Since the context is not completely initialized, this can cause confusion
as to whether the context is valid or not.

Move the fd reference from allocate_ctxt() to setup_base_ctxt().
Update the necessary functions to be aware of this move.

Reviewed-by: Sebastian Sanchez <sebastian.sanchez@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: Size rcd array index correctly and consistently

The array index for the rcd array is sized several different ways
throughout the code.

Use the user interface size (u16) as the standard size and update the
necessary code to reflect this.

u16 is large enough for the largest amount of supported contexts.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@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 unused user context data members

Several data members of the user context have become unused over time.
Cleaning them up.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
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 an assign/ordering issue with shared context IDs

The current algorithm for generating sub-context IDs is FILO. If the
contexts are not closed in that order, the uniqueness of the ID will be
compromised. I.e. logging the creation/deletion of context IDs with an
application that assigns and closes in a FIFO order reveals:

cache_id: assign: uctxt: 3 sub_ctxt: 0
cache_id: assign: uctxt: 3 sub_ctxt: 1
cache_id: assign: uctxt: 3 sub_ctxt: 2
cache_id: close: uctxt: 3 sub_ctxt: 0
cache_id: assign: uctxt: 3 sub_ctxt: 2 <<<

The sub_ctxt ID 2 is reused incorrectly.

Update the sub-context ID assign algorithm to use a bitmask of in_use
contexts. The new algorithm will allow the contexts to be closed in any
order, and will only re-use unused contexts.

Size subctxt and subctxt_cnt to match the user API size.

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: Use filedata rather than filepointer

Since almost all functions that use the hfi1_filedata get the pointer
from the file pointer, simplify by only passing the hfi1_filedata pointer.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@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: Name function prototype parameters

To improve the readability of function prototypes, give the parameters
names.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@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: Use evict mmu rb operation

Use the new cache evict operation in the SDMA code. This allows the cache
to properly coordinate evicts and removes, preventing any race. With this
change, the separate list, lock, and race flag are not needed.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Make the cache handler own its rb tree root

The objects which use cache handling should reference their own handler
object not the internal data structure it uses to track the nodes.

Have the "users" of the mmu notifier code pass opaque objects which can
then be properly used in the mmu callbacks depending on the owners needs.

This patch has the additional benefit that operations no longer require a
look up in a list to find the handlers.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Make use of mm consistent

The hfi1 driver registers a mmu_notifier callback when /dev/hfi1_* is
opened, and unregisters it when the device is closed. The driver
incorrectly assumes that the close will always happen from the same
context as the open. In particular, closes due to SIGKILL or OOM killer
activity may happen from a different context. In these cases, the wrong
mm is passed to mmu_notifier_unregister(), which causes improper reference
counting for the victim mm, and eventual memory corruption.

Preserve the mm for all open file descriptors and use this mm rather than
current->mm for memory operations for the lifetime of that fd. Note: this
patch leaves 1 use of current->mm in place. This use is removed in a
follow on patch because other functional changes were required prior to
that use being removed.

If registration fails, there is no reason to keep the handler object
around. Free the handler object rather than add it to the list to
prevent any mmu_notifier operations, including unregister, when
registration fails.

Suggested-by: Jim Foraker <foraker1@llnl.gov>
Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/hfi1: Fix user SDMA racy user request claim

The user SDMA in-use claim bit is in the structure that gets zeroed out
once the claim is made. Move the request in-use flag into its own bit
array and use that for atomic claims. This cleans up the claim code and
removes any race possibility.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@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>