200 Commits

Author SHA1 Message Date
Aharon Landau
3a57babfb6 RDMA/mlx5: Don't remove cache MRs when a delay is needed
[ Upstream commit 84c2362fb65d69c721fec0974556378cbb36a62b ]

Don't remove MRs from the cache if need to delay the removal.

Fixes: b9358bdbc713 ("RDMA/mlx5: Fix locking in MR cache work queue")
Link: https://lore.kernel.org/r/c3087a90ff362c8796c7eaa2715128743ce36722.1649062436.git.leonro@nvidia.com
Signed-off-by: Aharon Landau <aharonl@nvidia.com>
Reviewed-by: Shay Drory <shayd@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 21:01:05 +02:00
Aharon Landau
e462b0f518 RDMA/mlx5: Fix the flow of a miss in the allocation of a cache ODP MR
[ Upstream commit 2f0e60d5e9f96341a0c8a01be8878cdb3b29ff20 ]

When an ODP MR cache entry is empty and trying to allocate it, increment
the ent->miss counter and call to queue_adjust_cache_locked() to verify
the entry is balanced.

Fixes: aad719dcf379 ("RDMA/mlx5: Allow MRs to be created in the cache synchronously")
Link: https://lore.kernel.org/r/09503e295276dcacc92cb1d8aef1ad0961c99dc1.1644947594.git.leonro@nvidia.com
Signed-off-by: Aharon Landau <aharonl@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:40:17 +02:00
Aharon Landau
e74551ba93 RDMA/mlx5: Delay emptying a cache entry when a new MR is added to it recently
[ Upstream commit d6793ca97b76642b77629dd0783ec64782a50bdb ]

Fixing a typo that causes a cache entry to shrink immediately after adding
to it new MRs if the entry size exceeds the high limit.  In doing so, the
cache misses its purpose to prevent the creation of new mkeys on the
runtime by using the cached ones.

Fixes: b9358bdbc713 ("RDMA/mlx5: Fix locking in MR cache work queue")
Link: https://lore.kernel.org/r/fcb546986be346684a016f5ca23a0567399145fa.1627370131.git.leonro@nvidia.com
Signed-off-by: Aharon Landau <aharonl@nvidia.com>
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-12 13:22:06 +02:00
Maor Gottlieb
d9a7b8fcd0 RDMA/mlx5: Fix MR cache memory leak
[ Upstream commit e89938902927a54abebccc9537991aca5237dfaf ]

If the MR cache entry invalidation failed, then we detach this entry from
the cache, therefore we must to free the memory as well.

Allcation backtrace for the leaker:

    [<00000000d8e423b0>] alloc_cache_mr+0x23/0xc0 [mlx5_ib]
    [<000000001f21304c>] create_cache_mr+0x3f/0xf0 [mlx5_ib]
    [<000000009d6b45dc>] mlx5_ib_alloc_implicit_mr+0x41/0×210 [mlx5_ib]
    [<00000000879d0d68>] mlx5_ib_reg_user_mr+0x9e/0×6e0 [mlx5_ib]
    [<00000000be74bf89>] create_qp+0x2fc/0xf00 [ib_uverbs]
    [<000000001a532d22>] ib_uverbs_handler_UVERBS_METHOD_COUNTERS_READ+0x1d9/0×230 [ib_uverbs]
    [<0000000070f46001>] rdma_alloc_commit_uobject+0xb5/0×120 [ib_uverbs]
    [<000000006d8a0b38>] uverbs_alloc+0x2b/0xf0 [ib_uverbs]
    [<00000000075217c9>] ksysioctl+0x234/0×7d0
    [<00000000eb5c120b>] __x64_sys_ioctl+0x16/0×20
    [<00000000db135b48>] do_syscall_64+0x59/0×2e0

Fixes: 1769c4c57548 ("RDMA/mlx5: Always remove MRs from the cache before destroying them")
Link: https://lore.kernel.org/r/20201213132940.345554-2-leon@kernel.org
Signed-off-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:53:53 +01:00
Jason Gunthorpe
c5c1af1107 RDMA/mlx5: Fix corruption of reg_pages in mlx5_ib_rereg_user_mr()
[ Upstream commit fc3325701a6353594083f08e297d4c1965c601aa ]

reg_pages should always contain mr->npage since when the mr is finally
de-reg'd it is always subtracted out.

If there were any error exits then mlx5_ib_rereg_user_mr() would leave the
reg_pages adjusted and this will cause it to be double subtracted
eventually.

The manipulation of reg_pages is inherently connected to the umem, so lift
it out of set_mr_fields() and only adjust it around creating/destroying a
umem.

reg_pages is only used for diagnostics in sysfs.

Fixes: 7d0cc6edcc70 ("IB/mlx5: Add MR cache for large UMR regions")
Link: https://lore.kernel.org/r/20201026131936.1335664-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:53:01 +01:00
Yishai Hadas
a03bfc37d5 RDMA/mlx5: Sync device with CPU pages upon ODP MR registration
Sync device with CPU pages upon ODP MR registration. mlx5 already has to
zero the HW's version of the PAS list, may as well deliver a PAS list that
matches the current CPU page tables configuration.

Link: https://lore.kernel.org/r/20200930163828.1336747-5-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-10-01 16:44:44 -03:00
Yishai Hadas
677cf51f71 RDMA/mlx5: Extend advice MR to support non faulting mode
Extend advice MR to support non faulting mode, this can improve
performance by increasing the populated page tables in the device.

Link: https://lore.kernel.org/r/20200930163828.1336747-4-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-10-01 16:44:05 -03:00
Jason Gunthorpe
8383da3e4a RDMA/mlx5: Clarify what the UMR is for when creating MRs
Once a mkey is created it can be modified using UMR. This is desirable for
performance reasons. However, different hardware has restrictions on what
modifications are possible using UMR. Make sense of these checks:

- mlx5_ib_can_reconfig_with_umr() returns true if the access flags can be
  altered. Most cases create MRs using 0 access flags (now made clear by
  consistent use of set_mkc_access_pd_addr_fields()), but the old logic
  here was tormented. Make it clear that this is checking if the current
  access_flags can be modified using UMR to different access_flags. It is
  always OK to use UMR to change flags that all HW supports.

- mlx5_ib_can_load_pas_with_umr() returns true if UMR can be used to
  enable and update the PAS/XLT. Enabling requires updating the entity
  size, so UMR ends up completely disabled on this old hardware. Make it
  clear why it is disabled. FRWR, ODP and cache always requires
  mlx5_ib_can_load_pas_with_umr().

- mlx5_ib_pas_fits_in_mr() is used to tell if an existing MR can be
  resized to hold a new PAS list. This only works for cached MR's because
  we don't store the PAS list size in other cases.

To be very clear, arrange things so any pre-created MR's in the cache
check the newly requested access_flags before allowing the MR to leave the
cache. If UMR cannot set the required access_flags the cache fails to
create the MR.

This in turn means relaxed ordering and atomic are now correctly blocked
early for implicit ODP on older HW.

Link: https://lore.kernel.org/r/20200914112653.345244-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-09-18 13:02:43 -03:00
Jason Gunthorpe
5eb29f0d13 RDMA/mlx5: Make mkeys always owned by the kernel's PD when not enabled
Any mkey that is not enabled and assigned to userspace should have the PD
set to a kernel owned PD.

When cache entries are created for the first time the PDN is set to 0,
which is probably a kernel PD, but be explicit.

When a MR is registered using the hybrid reg_create with UMR xlt & enable
the disabled mkey is pointing at the user PD, keep it pointing at the
kernel until a UMR enables it and sets the user PD.

Fixes: 9ec4483a3f0f ("IB/mlx5: Move MRs to a kernel PD when freeing them to the MR cache")
Link: https://lore.kernel.org/r/20200914112653.345244-4-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-09-18 13:02:43 -03:00
Jason Gunthorpe
1c97ca3da0 RDMA/mlx5: Use set_mkc_access_pd_addr_fields() in reg_create()
reg_create() open codes this helper, use the shared code.

Link: https://lore.kernel.org/r/20200914112653.345244-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-09-18 13:02:42 -03:00
Jason Gunthorpe
2e4e706e09 RDMA/mlx5: Remove dead check for EAGAIN after alloc_mr_from_cache()
alloc_mr_from_cache() no longer returns EAGAIN, this is just dead code
now.

Fixes: aad719dcf379 ("RDMA/mlx5: Allow MRs to be created in the cache synchronously")
Link: https://lore.kernel.org/r/20200914112653.345244-2-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-09-18 13:02:42 -03:00
Leon Romanovsky
d18bb3e152 RDMA: Clean MW allocation and free flows
Move allocation and destruction of memory windows under ib_core
responsibility and clean drivers to ensure that no updates to MW
ib_core structures are done in driver layer.

Link: https://lore.kernel.org/r/20200902081623.746359-2-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-09-17 14:04:32 -03:00
Leon Romanovsky
70c1430fba RDMA/mlx5: Replace open-coded offsetofend() macro
Clean mlx5_ib from open-coded implementations of offsetofend().

Link: https://lore.kernel.org/r/20200730081235.1581127-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-08-18 14:47:34 -03:00
Gal Pressman
42a3b15396 RDMA: Remove the udata parameter from alloc_mr callback
Allocating an MR flow can only be initiated by kernel users, and not from
userspace so a udata parameter is redundant.

Link: https://lore.kernel.org/r/20200706120343.10816-4-galpress@amazon.com
Signed-off-by: Gal Pressman <galpress@amazon.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-07-06 19:25:53 -03:00
Maor Gottlieb
189277f381 RDMA/mlx5: Fix NULL pointer dereference in destroy_prefetch_work
q_deferred_work isn't initialized when creating an explicit ODP memory
region. This can lead to a NULL pointer dereference when user performs
asynchronous prefetch MR. Fix it by initializing q_deferred_work for
explicit ODP.

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP PTI
  CPU: 4 PID: 6074 Comm: kworker/u16:6 Not tainted 5.7.0-rc1-for-upstream-perf-2020-04-17_07-03-39-64 #1
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
  Workqueue: events_unbound mlx5_ib_prefetch_mr_work [mlx5_ib]
  RIP: 0010:__wake_up_common+0x49/0x120
  Code: 04 89 54 24 0c 89 4c 24 08 74 0a 41 f6 01 04 0f 85 8e 00 00 00 48 8b 47 08 48 83 e8 18 4c 8d 67 08 48 8d 50 18 49 39 d4 74 66 <48> 8b 70 18 31 db 4c 8d 7e e8 eb 17 49 8b 47 18 48 8d 50 e8 49 8d
  RSP: 0000:ffffc9000097bd88 EFLAGS: 00010082
  RAX: ffffffffffffffe8 RBX: ffff888454cd9f90 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffff888454cd9f90
  RBP: ffffc9000097bdd0 R08: 0000000000000000 R09: ffffc9000097bdd0
  R10: 0000000000000000 R11: 0000000000000001 R12: ffff888454cd9f98
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003
  FS:  0000000000000000(0000) GS:ffff88846fd00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 000000044c19e002 CR4: 0000000000760ee0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
   __wake_up_common_lock+0x7a/0xc0
   destroy_prefetch_work+0x5a/0x60 [mlx5_ib]
   mlx5_ib_prefetch_mr_work+0x64/0x80 [mlx5_ib]
   process_one_work+0x15b/0x360
   worker_thread+0x49/0x3d0
   kthread+0xf5/0x130
   ? rescuer_thread+0x310/0x310
   ? kthread_bind+0x10/0x10
   ret_from_fork+0x1f/0x30

Fixes: de5ed007a03d ("IB/mlx5: Fix implicit ODP race")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200521072504.567406-1-leon@kernel.org
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-05-21 20:51:50 -03:00
Jason Gunthorpe
aad719dcf3 RDMA/mlx5: Allow MRs to be created in the cache synchronously
If the cache is completely out of MRs, and we are running in cache mode,
then directly, and synchronously, create an MR that is compatible with the
cache bucket using a sleeping mailbox command. This ensures that the
thread that is waiting for the MR absolutely will get one.

When a MR allocated in this way becomes freed then it is compatible with
the cache bucket and will be recycled back into it.

Deletes the very buggy ent->compl scheme to create a synchronous MR
allocation.

Link: https://lore.kernel.org/r/20200310082238.239865-13-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:02 -03:00
Jason Gunthorpe
1c78a21a0c RDMA/mlx5: Revise how the hysteresis scheme works for cache filling
Currently if the work queue is running then it is in 'hysteresis' mode and
will fill until the cache reaches the high water mark. This implicit state
is very tricky and doesn't interact with pending very well.

Instead of self re-scheduling the work queue after the add_keys() has
started to create the new MR, have the queue scheduled from
reg_mr_callback() only after the requested MR has been added.

This avoids the bad design of an in-rush of queue'd work doing back to
back add_keys() until EAGAIN then sleeping. The add_keys() will be paced
one at a time as they complete, slowly filling up the cache.

Also, fix pending to be only manipulated under lock.

Link: https://lore.kernel.org/r/20200310082238.239865-12-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:02 -03:00
Jason Gunthorpe
b9358bdbc7 RDMA/mlx5: Fix locking in MR cache work queue
All of the members of mlx5_cache_ent must be accessed while holding the
spinlock, add the missing spinlock in the __cache_work_func().

Using cache->stopped and flush_workqueue() is an inherently racy way to
shutdown self-scheduling work on a queue. Replace it with ent->disabled
under lock, and always check disabled before queuing any new work. Use
cancel_work_sync() to shutdown the queue.

Use READ_ONCE/WRITE_ONCE for dev->last_add to manage concurrency as
coherency is less important here.

Split fill_delay from the bitfield. C bitfield updates are not atomic and
this is just a mess. Use READ_ONCE/WRITE_ONCE, but this could also use
test_bit()/set_bit().

Link: https://lore.kernel.org/r/20200310082238.239865-11-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:02 -03:00
Jason Gunthorpe
ad2d3ef46d RDMA/mlx5: Lock access to ent->available_mrs/limit when doing queue_work
Accesses to these members needs to be locked. There is no reason not to
hold a spinlock while calling queue_work(), so move the tests into a
helper and always call it under lock.

The helper should be called when available_mrs is adjusted.

Link: https://lore.kernel.org/r/20200310082238.239865-10-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:01 -03:00
Jason Gunthorpe
a1d8854aae RDMA/mlx5: Fix MR cache size and limit debugfs
The size_write function is supposed to adjust the total_mr's to match the
user's request, but lacks locking and safety checking.

total_mrs can only be adjusted by at most available_mrs. mrs already
assigned to users cannot be revoked. Ensure that the user provides a
target value within the range of available_mrs and within the high/low
water mark.

limit_write has confusing and wrong sanity checking, and doesn't have the
ability to deallocate on limit reduction.

Since both functions use the same algorithm to adjust the available_mrs,
consolidate it into one function and write it correctly. Fix the locking
and by holding the spinlock for all accesses to ent->X.

Always fail if the user provides a malformed string.

Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters")
Link: https://lore.kernel.org/r/20200310082238.239865-9-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:01 -03:00
Jason Gunthorpe
1769c4c575 RDMA/mlx5: Always remove MRs from the cache before destroying them
The cache bucket tracks the total number of MRs that exists, both inside
and outside of the cache. Removing a MR from the cache (by setting
cache_ent to NULL) without updating total_mrs will cause the tracking to
leak and be inflated.

Further fix the rereg_mr path to always destroy the MR. reg_create will
always overwrite all the MR data in mlx5_ib_mr, so the MR must be
completely destroyed, in all cases, before this function can be
called. Detach the MR from the cache and unconditionally destroy it to
avoid leaking HW mkeys.

Fixes: afd1417404fb ("IB/mlx5: Use direct mkey destroy command upon UMR unreg failure")
Fixes: 56e11d628c5d ("IB/mlx5: Added support for re-registration of MRs")
Link: https://lore.kernel.org/r/20200310082238.239865-8-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:01 -03:00
Jason Gunthorpe
b91e1751fb RDMA/mlx5: Simplify how the MR cache bucket is located
There are many bad APIs here that are accepting a cache bucket index
instead of a bucket pointer. Many of the callers already have a bucket
pointer, so this results in a lot of confusing uses of order2idx().

Pass the struct mlx5_cache_ent into add_keys(), remove_keys(), and
alloc_cached_mr().

Once the MR is in the cache, store the cache bucket pointer directly in
the MR, replacing the 'bool allocated_from cache'.

In the end there is only one place that needs to form index from order,
alloc_mr_from_cache(). Increase the safety of this function by disallowing
it from accessing cache entries in the ODP special area.

Link: https://lore.kernel.org/r/20200310082238.239865-7-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:01 -03:00
Jason Gunthorpe
7c8691a396 RDMA/mlx5: Rename the tracking variables for the MR cache
The old names do not clearly indicate the intent.

Link: https://lore.kernel.org/r/20200310082238.239865-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:01 -03:00
Saeed Mahameed
f743ff3b37 RDMA/mlx5: Replace spinlock protected write with atomic var
mkey variant calculation was spinlock protected to make it atomic, replace
that with one atomic variable.

Link: https://lore.kernel.org/r/20200310082238.239865-4-leon@kernel.org
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-13 11:08:00 -03:00
Michael Guralnik
a3cfdd3928 {IB,net}/mlx5: Move asynchronous mkey creation to mlx5_ib
As mlx5_ib is the only user of the mlx5_core_create_mkey_cb, move the
logic inside mlx5_ib and cleanup the code in mlx5_core.

Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2020-03-13 15:48:10 +02:00
Saeed Mahameed
fc6a9f86f0 {IB,net}/mlx5: Assign mkey variant in mlx5_ib only
mkey variant is not required for mlx5_core use, move the mkey variant
counter to mlx5_ib.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2020-03-13 15:48:04 +02:00
Saeed Mahameed
54c62e13ad {IB,net}/mlx5: Setup mkey variant before mr create command invocation
On reg_mr_callback() mlx5_ib is recalculating the mkey variant which is
wrong and will lead to using a different key variant than the one
submitted to firmware on create mkey command invocation.

To fix this, we store the mkey variant before invoking the firmware
command and use it later on completion (reg_mr_callback).

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2020-03-13 15:48:00 +02:00
Jason Gunthorpe
e8b3a426fb Use ODP MRs for kernel ULPs
The following series extends MR creation routines to allow creation of
 user MRs through kernel ULPs as a proxy. The immediate use case is to
 allow RDS to work over FS-DAX, which requires ODP (on-demand-paging)
 MRs to be created and such MRs were not possible to create prior this
 series.
 
 The first part of this patchset extends RDMA to have special verb
 ib_reg_user_mr(). The common use case that uses this function is a
 userspace application that allocates memory for HCA access but the
 responsibility to register the memory at the HCA is on an kernel ULP.
 This ULP acts as an agent for the userspace application.
 
 The second part provides advise MR functionality for ULPs. This is
 integral part of ODP flows and used to trigger pagefaults in advance
 to prepare memory before running working set.
 
 The third part is actual user of those in-kernel APIs.
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Merge tag 'rds-odp-for-5.5' into rdma.git for-next

From https://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma

Leon Romanovsky says:

====================
Use ODP MRs for kernel ULPs

The following series extends MR creation routines to allow creation of
user MRs through kernel ULPs as a proxy. The immediate use case is to
allow RDS to work over FS-DAX, which requires ODP (on-demand-paging)
MRs to be created and such MRs were not possible to create prior this
series.

The first part of this patchset extends RDMA to have special verb
ib_reg_user_mr(). The common use case that uses this function is a
userspace application that allocates memory for HCA access but the
responsibility to register the memory at the HCA is on an kernel ULP.
This ULP acts as an agent for the userspace application.

The second part provides advise MR functionality for ULPs. This is
integral part of ODP flows and used to trigger pagefaults in advance
to prepare memory before running working set.

The third part is actual user of those in-kernel APIs.
====================

* tag 'rds-odp-for-5.5':
  net/rds: Use prefetch for On-Demand-Paging MR
  net/rds: Handle ODP mr registration/unregistration
  net/rds: Detect need of On-Demand-Paging memory registration
  RDMA/mlx5: Fix handling of IOVA != user_va in ODP paths
  IB/mlx5: Mask out unsupported ODP capabilities for kernel QPs
  RDMA/mlx5: Don't fake udata for kernel path
  IB/mlx5: Add ODP WQE handlers for kernel QPs
  IB/core: Add interface to advise_mr for kernel users
  IB/core: Introduce ib_reg_user_mr
  IB: Allow calls to ib_umem_get from kernel ULPs

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-21 09:55:04 -04:00
Michael Guralnik
d6de0bb185 RDMA/mlx5: Set relaxed ordering when requested
Enable relaxed ordering in the mkey context when requested. As relaxed
ordering is not currently supported in UMR, disable UMR usage for relaxed
ordering MRs.

Link: https://lore.kernel.org/r/1578506740-22188-11-git-send-email-yishaih@mellanox.com
Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-16 15:55:47 -04:00
Jason Gunthorpe
8ffc324851 RDMA/mlx5: Fix handling of IOVA != user_va in ODP paths
Till recently it was not possible for userspace to specify a different
IOVA, but with the new ibv_reg_mr_iova() library call this can be done.

To compute the user_va we must compute:
  user_va = (iova - iova_start) + user_va_start

while being cautious of overflow and other math problems.

The iova is not reliably stored in the mmkey when the MR is created. Only
the cached creation path (the common one) set it, so it must also be set
when creating uncached MRs.

Fix the weird use of iova when computing the starting page index in the
MR. In the normal case, when iova == umem.address:
  iova & (~(BIT(page_shift) - 1)) ==
  ALIGN_DOWN(umem.address, odp->page_size) ==
  ib_umem_start(odp)

And when iova is different using it in math with a user_va is wrong.

Finally, do not allow an implicit ODP to be created with a non-zero IOVA
as we have no support for that.

Fixes: 7bdf65d411c1 ("IB/mlx5: Handle page faults")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2020-01-16 16:15:07 +02:00
Moni Shoua
c320e527e1 IB: Allow calls to ib_umem_get from kernel ULPs
So far the assumption was that ib_umem_get() and ib_umem_odp_get()
are called from flows that start in UVERBS and therefore has a user
context. This assumption restricts flows that are initiated by ULPs
and need the service that ib_umem_get() provides.

This patch changes ib_umem_get() and ib_umem_odp_get() to get IB device
directly by relying on the fact that both UVERBS and ULPs sets that
field correctly.

Reviewed-by: Guy Levi <guyle@mellanox.com>
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2020-01-16 16:14:28 +02:00
zhengbin
2ab367a70a RDMA/mlx5: use true,false for bool variable
Fixes coccicheck warning:

drivers/infiniband/hw/mlx5/mr.c:150:2-26: WARNING: Assignment of 0/1 to bool variable
drivers/infiniband/hw/mlx5/mr.c:1455:2-26: WARNING: Assignment of 0/1 to bool variable
drivers/infiniband/hw/mlx5/qp.c:1874:6-20: WARNING: Assignment of 0/1 to bool variable

Link: https://lore.kernel.org/r/1577176812-2238-6-git-send-email-zhengbin13@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-03 19:14:00 -04:00
Artemy Kovalyov
cbe4b8f0a5 IB/mlx5: Unify ODP MR code paths to allow extra flexibility
Building MR translation table in the ODP case requires additional
flexibility, namely random access to DMA addresses. Make both direct and
indirect ODP MR use same code path, separated from the non-ODP MR code
path.

With the restructuring the correct page_shift is now used around
__mlx5_ib_populate_pas().

Fixes: d2183c6f1958 ("RDMA/umem: Move page_shift from ib_umem to ib_odp_umem")
Link: https://lore.kernel.org/r/20191222124649.52300-2-leon@kernel.org
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-03 17:00:13 -04:00
Linus Torvalds
aa32f11691 hmm related patches for 5.5
This is another round of bug fixing and cleanup. This time the focus is on
 the driver pattern to use mmu notifiers to monitor a VA range. This code
 is lifted out of many drivers and hmm_mirror directly into the
 mmu_notifier core and written using the best ideas from all the driver
 implementations.
 
 This removes many bugs from the drivers and has a very pleasing
 diffstat. More drivers can still be converted, but that is for another
 cycle.
 
 - A shared branch with RDMA reworking the RDMA ODP implementation
 
 - New mmu_interval_notifier API. This is focused on the use case of
   monitoring a VA and simplifies the process for drivers
 
 - A common seq-count locking scheme built into the mmu_interval_notifier
   API usable by drivers that call get_user_pages() or hmm_range_fault()
   with the VA range
 
 - Conversion of mlx5 ODP, hfi1, radeon, nouveau, AMD GPU, and Xen GntDev
   drivers to the new API. This deletes a lot of wonky driver code.
 
 - Two improvements for hmm_range_fault(), from testing done by Ralph
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Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull hmm updates from Jason Gunthorpe:
 "This is another round of bug fixing and cleanup. This time the focus
  is on the driver pattern to use mmu notifiers to monitor a VA range.
  This code is lifted out of many drivers and hmm_mirror directly into
  the mmu_notifier core and written using the best ideas from all the
  driver implementations.

  This removes many bugs from the drivers and has a very pleasing
  diffstat. More drivers can still be converted, but that is for another
  cycle.

   - A shared branch with RDMA reworking the RDMA ODP implementation

   - New mmu_interval_notifier API. This is focused on the use case of
     monitoring a VA and simplifies the process for drivers

   - A common seq-count locking scheme built into the
     mmu_interval_notifier API usable by drivers that call
     get_user_pages() or hmm_range_fault() with the VA range

   - Conversion of mlx5 ODP, hfi1, radeon, nouveau, AMD GPU, and Xen
     GntDev drivers to the new API. This deletes a lot of wonky driver
     code.

   - Two improvements for hmm_range_fault(), from testing done by Ralph"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  mm/hmm: remove hmm_range_dma_map and hmm_range_dma_unmap
  mm/hmm: make full use of walk_page_range()
  xen/gntdev: use mmu_interval_notifier_insert
  mm/hmm: remove hmm_mirror and related
  drm/amdgpu: Use mmu_interval_notifier instead of hmm_mirror
  drm/amdgpu: Use mmu_interval_insert instead of hmm_mirror
  drm/amdgpu: Call find_vma under mmap_sem
  nouveau: use mmu_interval_notifier instead of hmm_mirror
  nouveau: use mmu_notifier directly for invalidate_range_start
  drm/radeon: use mmu_interval_notifier_insert
  RDMA/hfi1: Use mmu_interval_notifier_insert for user_exp_rcv
  RDMA/odp: Use mmu_interval_notifier_insert()
  mm/hmm: define the pre-processor related parts of hmm.h even if disabled
  mm/hmm: allow hmm_range to be used with a mmu_interval_notifier or hmm_mirror
  mm/mmu_notifier: add an interval tree notifier
  mm/mmu_notifier: define the header pre-processor parts even if disabled
  mm/hmm: allow snapshot of the special zero page
2019-11-30 10:33:14 -08:00
Jason Gunthorpe
f25a546e65 RDMA/odp: Use mmu_interval_notifier_insert()
Replace the internal interval tree based mmu notifier with the new common
mmu_interval_notifier_insert() API. This removes a lot of code and fixes a
deadlock that can be triggered in ODP:

 zap_page_range()
  mmu_notifier_invalidate_range_start()
   [..]
    ib_umem_notifier_invalidate_range_start()
       down_read(&per_mm->umem_rwsem)
  unmap_single_vma()
    [..]
      __split_huge_page_pmd()
        mmu_notifier_invalidate_range_start()
        [..]
           ib_umem_notifier_invalidate_range_start()
              down_read(&per_mm->umem_rwsem)   // DEADLOCK

        mmu_notifier_invalidate_range_end()
           up_read(&per_mm->umem_rwsem)
  mmu_notifier_invalidate_range_end()
     up_read(&per_mm->umem_rwsem)

The umem_rwsem is held across the range_start/end as the ODP algorithm for
invalidate_range_end cannot tolerate changes to the interval
tree. However, due to the nested invalidation regions the second
down_read() can deadlock if there are competing writers. The new core code
provides an alternative scheme to solve this problem.

Fixes: ca748c39ea3f ("RDMA/umem: Get rid of per_mm->notifier_count")
Link: https://lore.kernel.org/r/20191112202231.3856-6-jgg@ziepe.ca
Tested-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-11-23 19:56:44 -04:00
Christoph Hellwig
72b894b09a IB/umem: remove the dmasync argument to ib_umem_get
The argument is always ignored, so remove it.

Link: https://lore.kernel.org/r/20191113073214.9514-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-11-17 10:37:00 -04:00
Leon Romanovsky
546d30099e RDMA/mlx5: Return proper error value
Returned value from mlx5_mr_cache_alloc() is checked to be error or real
pointer. Return proper error code instead of NULL which is not checked
later.

Fixes: 81713d3788d2 ("IB/mlx5: Add implicit MR support")
Link: https://lore.kernel.org/r/20191029055721.7192-1-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-31 15:31:49 -03:00
Jason Gunthorpe
bb3dba3300 Merge branch 'odp_rework' into rdma.git for-next
Jason Gunthorpe says:

====================
In order to hoist the interval tree code out of the drivers and into the
mmu_notifiers it is necessary for the drivers to not use the interval tree
for other things.

This series replaces the interval tree with an xarray and along the way
re-aligns all the locking to use a sensible SRCU model where the 'update'
step is done by modifying an xarray.

The result is overall much simpler and with less locking in the critical
path. Many functions were reworked for clarity and small details like
using 'imr' to refer to the implicit MR make the entire code flow here
more readable.

This also squashes at least two race bugs on its own, and quite possibily
more that haven't been identified.
====================

Merge conflicts with the odp statistics patch resolved.

* branch 'odp_rework':
  RDMA/odp: Remove broken debugging call to invalidate_range
  RDMA/mlx5: Do not race with mlx5_ib_invalidate_range during create and destroy
  RDMA/mlx5: Do not store implicit children in the odp_mkeys xarray
  RDMA/mlx5: Rework implicit ODP destroy
  RDMA/mlx5: Avoid double lookups on the pagefault path
  RDMA/mlx5: Reduce locking in implicit_mr_get_data()
  RDMA/mlx5: Use an xarray for the children of an implicit ODP
  RDMA/mlx5: Split implicit handling from pagefault_mr
  RDMA/mlx5: Set the HW IOVA of the child MRs to their place in the tree
  RDMA/mlx5: Lift implicit_mr_alloc() into the two routines that call it
  RDMA/mlx5: Rework implicit_mr_get_data
  RDMA/mlx5: Delete struct mlx5_priv->mkey_table
  RDMA/mlx5: Use a dedicated mkey xarray for ODP
  RDMA/mlx5: Split sig_err MR data into its own xarray
  RDMA/mlx5: Use SRCU properly in ODP prefetch

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-28 16:47:52 -03:00
Jason Gunthorpe
09689703d2 RDMA/mlx5: Do not race with mlx5_ib_invalidate_range during create and destroy
For creation, as soon as the umem_odp is created the notifier can be
called, however the underlying MR may not have been setup yet. This would
cause problems if mlx5_ib_invalidate_range() runs. There is some
confusing/ulocked/racy code that might by trying to solve this, but
without locks it isn't going to work right.

Instead trivially solve the problem by short-circuiting the invalidation
if there are not yet any DMA mapped pages. By definition there is nothing
to invalidate in this case.

The create code will have the umem fully setup before anything is DMA
mapped, and npages is fully locked by the umem_mutex.

For destroy, invalidate the entire MR at the HW to stop DMA then DMA unmap
the pages before destroying the MR. This drives npages to zero and
prevents similar racing with invalidate while the MR is undergoing
destruction.

Arguably it would be better if the umem was created after the MR and
destroyed before, but that would require a big rework of the MR code.

Fixes: 6aec21f6a832 ("IB/mlx5: Page faults handling infrastructure")
Link: https://lore.kernel.org/r/20191009160934.3143-15-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-28 16:41:14 -03:00
Jason Gunthorpe
5256edcb98 RDMA/mlx5: Rework implicit ODP destroy
Use SRCU in a sensible way by removing all MRs in the implicit tree from
the two xarrays (the update operation), then a synchronize, followed by a
normal single threaded teardown.

This is only a little unusual from the normal pattern as there can still
be some work pending in the unbound wq that may also require a workqueue
flush. This is tracked with a single atomic, consolidating the redundant
existing atomics and wait queue.

For understand-ability the entire ODP implicit create/destroy flow now
largely exists in a single pair of functions within odp.c, with a few
support functions for tearing down an unused child.

Link: https://lore.kernel.org/r/20191009160934.3143-13-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-28 16:41:14 -03:00
Jason Gunthorpe
74bddb3682 RDMA/mlx5: Delete struct mlx5_priv->mkey_table
No users are left, delete it.

Link: https://lore.kernel.org/r/20191009160934.3143-5-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-28 16:41:13 -03:00
Jason Gunthorpe
806b101b2b RDMA/mlx5: Use a dedicated mkey xarray for ODP
There is a per device xarray storing mkeys that is used to store every
mkey in the system. However, this xarray is now only read by ODP for
certain ODP designated MRs (ODP, implicit ODP, MW, DEVX_INDIRECT).

Create an xarray only for use by ODP, that only contains ODP related
MKeys. This xarray is protected by SRCU and all erases are protected by a
synchronize.

This improves performance:

 - All MRs in the odp_mkeys xarray are ODP MRs, so some tests for is_odp()
   can be deleted. The xarray will also consume fewer nodes.

 - normal MR's are never mixed with ODP MRs in a SRCU data structure so
   performance sucking synchronize_srcu() on every MR destruction is not
   needed.

 - No smp_load_acquire(live) and xa_load() double barrier on read

Due to the SRCU locking scheme care must be taken with the placement of
the xa_store(). Once it completes the MR is immediately visible to other
threads and only through a xa_erase() & synchronize_srcu() cycle could it
be destroyed.

Link: https://lore.kernel.org/r/20191009160934.3143-4-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-28 16:41:13 -03:00
Jason Gunthorpe
50211ec944 RDMA/mlx5: Split sig_err MR data into its own xarray
The locking model for signature is completely different than ODP, do not
share the same xarray that relies on SRCU locking to support ODP.

Simply store the active mlx5_core_sig_ctx's in an xarray when signature
MRs are created and rely on trivial xarray locking to serialize
everything.

The overhead of storing only a handful of SIG related MRs is going to be
much less than an xarray full of every mkey.

Link: https://lore.kernel.org/r/20191009160934.3143-3-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-28 16:41:13 -03:00
Jason Gunthorpe
036313316d Linux 5.4-rc5
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Merge tag 'v5.4-rc5' into rdma.git for-next

Linux 5.4-rc5

For dependencies in the next patches

Conflict resolved by keeping the delete of the unlock.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-28 16:36:29 -03:00
Parav Pandit
03232cc43c IB/mlx5: Introduce and use mkey context setting helper routine
Introduce and use set_mkc_access_pd_addr_fields() which sets mkey
context's access rights, PD, address fields.  Thereby avoid the code
duplication.

Link: https://lore.kernel.org/r/20191006155443.31068-1-leon@kernel.org
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-08 16:45:07 -03:00
Jason Gunthorpe
0417791536 RDMA/mlx5: Add missing synchronize_srcu() for MW cases
While MR uses live as the SRCU 'update', the MW case uses the xarray
directly, xa_erase() causes the MW to become inaccessible to the pagefault
thread.

Thus whenever a MW is removed from the xarray we must synchronize_srcu()
before freeing it.

This must be done before freeing the mkey as re-use of the mkey while the
pagefault thread is using the stale mkey is undesirable.

Add the missing synchronizes to MW and DEVX indirect mkey and delete the
bogus protection against double destroy in mlx5_core_destroy_mkey()

Fixes: 534fd7aac56a ("IB/mlx5: Manage indirection mkey upon DEVX flow for ODP")
Fixes: 6aec21f6a832 ("IB/mlx5: Page faults handling infrastructure")
Link: https://lore.kernel.org/r/20191001153821.23621-7-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-04 15:54:22 -03:00
Jason Gunthorpe
aa603815c7 RDMA/mlx5: Put live in the correct place for ODP MRs
live is used to signal to the pagefault thread that the MR is initialized
and ready for use. It should be after the umem is assigned and all other
setup is completed. This prevents races (at least) of the form:

    CPU0                                     CPU1
mlx5_ib_alloc_implicit_mr()
 implicit_mr_alloc()
  live = 1
 imr->umem = umem
                                    num_pending_prefetch_inc()
                                      if (live)
				        atomic_inc(num_pending_prefetch)
 atomic_set(num_pending_prefetch,0) // Overwrites other thread's store

Further, live is being used with SRCU as the 'update' in an
acquire/release fashion, so it can not be read and written raw.

Move all live = 1's to after MR initialization is completed and use
smp_store_release/smp_load_acquire() for manipulating it.

Add a missing live = 0 when an implicit MR child is deleted, before
queuing work to do synchronize_srcu().

The barriers in update_odp_mr() were some broken attempt to create a
acquire/release, but were not even applied consistently and missed the
point, delete it as well.

Fixes: 6aec21f6a832 ("IB/mlx5: Page faults handling infrastructure")
Link: https://lore.kernel.org/r/20191001153821.23621-6-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-04 15:54:22 -03:00
Jason Gunthorpe
aa116b810a RDMA/mlx5: Order num_pending_prefetch properly with synchronize_srcu
During destroy setting live = 0 and then synchronize_srcu() prevents
num_pending_prefetch from incrementing, and also, ensures that all work
holding that count is queued on the WQ. Testing before causes races of the
form:

    CPU0                                         CPU1
  dereg_mr()
                                          mlx5_ib_advise_mr_prefetch()
            				   srcu_read_lock()
                                            num_pending_prefetch_inc()
					      if (!live)
   live = 0
   atomic_read() == 0
     // skip flush_workqueue()
                                              atomic_inc()
 					      queue_work();
            				   srcu_read_unlock()
   WARN_ON(atomic_read())  // Fails

Swap the order so that the synchronize_srcu() prevents this.

Fixes: a6bc3875f176 ("IB/mlx5: Protect against prefetch of invalid MR")
Link: https://lore.kernel.org/r/20191001153821.23621-5-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-04 15:54:22 -03:00
Jason Gunthorpe
880505cfef RDMA/mlx5: Do not allow rereg of a ODP MR
This code is completely broken, the umem of a ODP MR simply cannot be
discarded without a lot more locking, nor can an ODP mkey be blithely
destroyed via destroy_mkey().

Fixes: 6aec21f6a832 ("IB/mlx5: Page faults handling infrastructure")
Link: https://lore.kernel.org/r/20191001153821.23621-2-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-10-04 15:54:21 -03:00
Linus Torvalds
84da111de0 hmm related patches for 5.4
This is more cleanup and consolidation of the hmm APIs and the very
 strongly related mmu_notifier interfaces. Many places across the tree
 using these interfaces are touched in the process. Beyond that a cleanup
 to the page walker API and a few memremap related changes round out the
 series:
 
 - General improvement of hmm_range_fault() and related APIs, more
   documentation, bug fixes from testing, API simplification &
   consolidation, and unused API removal
 
 - Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE, and
   make them internal kconfig selects
 
 - Hoist a lot of code related to mmu notifier attachment out of drivers by
   using a refcount get/put attachment idiom and remove the convoluted
   mmu_notifier_unregister_no_release() and related APIs.
 
 - General API improvement for the migrate_vma API and revision of its only
   user in nouveau
 
 - Annotate mmu_notifiers with lockdep and sleeping region debugging
 
 Two series unrelated to HMM or mmu_notifiers came along due to
 dependencies:
 
 - Allow pagemap's memremap_pages family of APIs to work without providing
   a struct device
 
 - Make walk_page_range() and related use a constant structure for function
   pointers
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Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull hmm updates from Jason Gunthorpe:
 "This is more cleanup and consolidation of the hmm APIs and the very
  strongly related mmu_notifier interfaces. Many places across the tree
  using these interfaces are touched in the process. Beyond that a
  cleanup to the page walker API and a few memremap related changes
  round out the series:

   - General improvement of hmm_range_fault() and related APIs, more
     documentation, bug fixes from testing, API simplification &
     consolidation, and unused API removal

   - Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE,
     and make them internal kconfig selects

   - Hoist a lot of code related to mmu notifier attachment out of
     drivers by using a refcount get/put attachment idiom and remove the
     convoluted mmu_notifier_unregister_no_release() and related APIs.

   - General API improvement for the migrate_vma API and revision of its
     only user in nouveau

   - Annotate mmu_notifiers with lockdep and sleeping region debugging

  Two series unrelated to HMM or mmu_notifiers came along due to
  dependencies:

   - Allow pagemap's memremap_pages family of APIs to work without
     providing a struct device

   - Make walk_page_range() and related use a constant structure for
     function pointers"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (75 commits)
  libnvdimm: Enable unit test infrastructure compile checks
  mm, notifier: Catch sleeping/blocking for !blockable
  kernel.h: Add non_block_start/end()
  drm/radeon: guard against calling an unpaired radeon_mn_unregister()
  csky: add missing brackets in a macro for tlb.h
  pagewalk: use lockdep_assert_held for locking validation
  pagewalk: separate function pointers from iterator data
  mm: split out a new pagewalk.h header from mm.h
  mm/mmu_notifiers: annotate with might_sleep()
  mm/mmu_notifiers: prime lockdep
  mm/mmu_notifiers: add a lockdep map for invalidate_range_start/end
  mm/mmu_notifiers: remove the __mmu_notifier_invalidate_range_start/end exports
  mm/hmm: hmm_range_fault() infinite loop
  mm/hmm: hmm_range_fault() NULL pointer bug
  mm/hmm: fix hmm_range_fault()'s handling of swapped out pages
  mm/mmu_notifiers: remove unregister_no_release
  RDMA/odp: remove ib_ucontext from ib_umem
  RDMA/odp: use mmu_notifier_get/put for 'struct ib_ucontext_per_mm'
  RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr
  RDMA/mlx5: Use ib_umem_start instead of umem.address
  ...
2019-09-21 10:07:42 -07:00