Fix a nested dead lock as part of ODP flow by using mmput_async().
From the below call trace [1] can see that calling mmput() once we have
the umem_odp->umem_mutex locked as required by
ib_umem_odp_map_dma_and_lock() might trigger in the same task the
exit_mmap()->__mmu_notifier_release()->mlx5_ib_invalidate_range() which
may dead lock when trying to lock the same mutex.
Moving to use mmput_async() will solve the problem as the above
exit_mmap() flow will be called in other task and will be executed once
the lock will be available.
[1]
[64843.077665] task:kworker/u133:2 state:D stack: 0 pid:80906 ppid:
2 flags:0x00004000
[64843.077672] Workqueue: mlx5_ib_page_fault mlx5_ib_eqe_pf_action [mlx5_ib]
[64843.077719] Call Trace:
[64843.077722] <TASK>
[64843.077724] __schedule+0x23d/0x590
[64843.077729] schedule+0x4e/0xb0
[64843.077735] schedule_preempt_disabled+0xe/0x10
[64843.077740] __mutex_lock.constprop.0+0x263/0x490
[64843.077747] __mutex_lock_slowpath+0x13/0x20
[64843.077752] mutex_lock+0x34/0x40
[64843.077758] mlx5_ib_invalidate_range+0x48/0x270 [mlx5_ib]
[64843.077808] __mmu_notifier_release+0x1a4/0x200
[64843.077816] exit_mmap+0x1bc/0x200
[64843.077822] ? walk_page_range+0x9c/0x120
[64843.077828] ? __cond_resched+0x1a/0x50
[64843.077833] ? mutex_lock+0x13/0x40
[64843.077839] ? uprobe_clear_state+0xac/0x120
[64843.077860] mmput+0x5f/0x140
[64843.077867] ib_umem_odp_map_dma_and_lock+0x21b/0x580 [ib_core]
[64843.077931] pagefault_real_mr+0x9a/0x140 [mlx5_ib]
[64843.077962] pagefault_mr+0xb4/0x550 [mlx5_ib]
[64843.077992] pagefault_single_data_segment.constprop.0+0x2ac/0x560
[mlx5_ib]
[64843.078022] mlx5_ib_eqe_pf_action+0x528/0x780 [mlx5_ib]
[64843.078051] process_one_work+0x22b/0x3d0
[64843.078059] worker_thread+0x53/0x410
[64843.078065] ? process_one_work+0x3d0/0x3d0
[64843.078073] kthread+0x12a/0x150
[64843.078079] ? set_kthread_struct+0x50/0x50
[64843.078085] ret_from_fork+0x22/0x30
[64843.078093] </TASK>
Fixes: 36f30e486d ("IB/core: Improve ODP to use hmm_range_fault()")
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/74d93541ea533ef7daec6f126deb1072500aeb16.1661251841.git.leonro@nvidia.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Enable ODP sync without faulting, this improves performance by reducing
the number of page faults in the system.
The gain from this option is that the device page table can be aligned
with the presented pages in the CPU page table without causing page
faults.
As of that, the overhead on data path from hardware point of view to
trigger a fault which end-up by calling the driver to bring the pages
will be dropped.
Link: https://lore.kernel.org/r/20200930163828.1336747-3-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>
Move to use hmm_range_fault() instead of get_user_pags_remote() to improve
performance in a few aspects:
This includes:
- Dropping the need to allocate and free memory to hold its output
- No need any more to use put_page() to unpin the pages
- The logic to detect contiguous pages is done based on the returned
order, no need to run per page and evaluate.
In addition, moving to use hmm_range_fault() enables to reduce page faults
in the system with it's snapshot mode, this will be introduced in next
patches from this series.
As part of this, cleanup some flows and use the required data structures
to work with hmm_range_fault().
Link: https://lore.kernel.org/r/20200930163828.1336747-2-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>
After the cleanup of page fault accounting, gup does not need to pass
task_struct around any more. Remove that parameter in the whole gup
stack.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Silence documentation build warnings by correcting kernel-doc comments.
./drivers/infiniband/core/verbs.c:1004: warning: Function parameter or member 'uobject' not described in 'ib_create_srq_user'
./drivers/infiniband/core/verbs.c:1004: warning: Function parameter or member 'udata' not described in 'ib_create_srq_user'
./drivers/infiniband/core/umem_odp.c:161: warning: Function parameter or member 'ops' not described in 'ib_umem_odp_alloc_child'
./drivers/infiniband/core/umem_odp.c:225: warning: Function parameter or member 'ops' not described in 'ib_umem_odp_get'
./drivers/infiniband/sw/rdmavt/ah.c:104: warning: Excess function parameter 'ah_attr' description in 'rvt_create_ah'
./drivers/infiniband/sw/rdmavt/ah.c:104: warning: Excess function parameter 'create_flags' description in 'rvt_create_ah'
./drivers/infiniband/ulp/iser/iscsi_iser.h:363: warning: Function parameter or member 'all_list' not described in 'iser_fr_desc'
./drivers/infiniband/ulp/iser/iscsi_iser.h:377: warning: Function parameter or member 'all_list' not described in 'iser_fr_pool'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:148: warning: Function parameter or member 'rsvd0' not described in 'opa_vesw_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:148: warning: Function parameter or member 'rsvd1' not described in 'opa_vesw_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:148: warning: Function parameter or member 'rsvd2' not described in 'opa_vesw_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:148: warning: Function parameter or member 'rsvd3' not described in 'opa_vesw_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:148: warning: Function parameter or member 'rsvd4' not described in 'opa_vesw_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:205: warning: Function parameter or member 'rsvd0' not described in 'opa_per_veswport_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:205: warning: Function parameter or member 'rsvd1' not described in 'opa_per_veswport_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:205: warning: Function parameter or member 'rsvd2' not described in 'opa_per_veswport_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:205: warning: Function parameter or member 'rsvd3' not described in 'opa_per_veswport_info'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:342: warning: Function parameter or member 'reserved' not described in 'opa_veswport_summary_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd0' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd1' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd2' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd3' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd4' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd5' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd6' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd7' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd8' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:394: warning: Function parameter or member 'rsvd9' not described in 'opa_veswport_error_counters'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:460: warning: Function parameter or member 'reserved' not described in 'opa_vnic_vema_mad'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:485: warning: Function parameter or member 'reserved' not described in 'opa_vnic_notice_attr'
./drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.h:500: warning: Function parameter or member 'reserved' not described in 'opa_vnic_vema_mad_trap'
Link: https://lore.kernel.org/r/5373936.DvuYhMxLoT@laptop.coltonlewis.name
Signed-off-by: Colton Lewis <colton.w.lewis@protonmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The tgid used to be part of ib_umem_free_notifier(), when it was reworked
it got moved to release, but it should have been unconditional as all umem
alloc paths get the tgid.
As is, creating an implicit ODP will leak the tgid reference.
Link: https://lore.kernel.org/r/20200304181607.GA22412@ziepe.ca
Cc: stable@kernel.org
Fixes: f25a546e65 ("RDMA/odp: Use mmu_interval_notifier_insert()")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Registration of a mmu_notifier requires the caller to hold a mmget() on
the mm as registration is not permitted to race with exit_mmap(). There is
a BUG_ON inside the mmu_notifier to guard against this.
Normally creating a umem is done against current which implicitly holds
the mmget(), however an implicit ODP child is created from a pagefault
work queue and is not guaranteed to have a mmget().
Call mmget() around this registration and abort faulting if the MM has
gone to exit_mmap().
Before the patch below the notifier was registered when the implicit ODP
parent was created, so there was no chance to register a notifier outside
of current.
Fixes: c571feca2d ("RDMA/odp: use mmu_notifier_get/put for 'struct ib_ucontext_per_mm'")
Link: https://lore.kernel.org/r/20200227114118.94736-1-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
- Driver updates and cleanup for qedr, bnxt_re, hns, siw, mlx5, mlx4, rxe,
i40iw
- Larger series doing cleanup and rework for hns and hfi1.
- Some general reworking of the CM code to make it a little more
understandable
- Unify the different code paths connected to the uverbs FD scheme
- New UAPI ioctls conversions for get context and get async fd
- Trace points for CQ and CM portions of the RDMA stack
- mlx5 driver support for virtio-net formatted rings as RDMA raw ethernet QPs
- verbs support for setting the PCI-E relaxed ordering bit on DMA traffic
connected to a MR
- A couple of bug fixes that came too late to make rc7
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull rdma updates from Jason Gunthorpe:
"A very quiet cycle with few notable changes. Mostly the usual list of
one or two patches to drivers changing something that isn't quite rc
worthy. The subsystem seems to be seeing a larger number of rework and
cleanup style patches right now, I feel that several vendors are
prepping their drivers for new silicon.
Summary:
- Driver updates and cleanup for qedr, bnxt_re, hns, siw, mlx5, mlx4,
rxe, i40iw
- Larger series doing cleanup and rework for hns and hfi1.
- Some general reworking of the CM code to make it a little more
understandable
- Unify the different code paths connected to the uverbs FD scheme
- New UAPI ioctls conversions for get context and get async fd
- Trace points for CQ and CM portions of the RDMA stack
- mlx5 driver support for virtio-net formatted rings as RDMA raw
ethernet QPs
- verbs support for setting the PCI-E relaxed ordering bit on DMA
traffic connected to a MR
- A couple of bug fixes that came too late to make rc7"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (108 commits)
RDMA/core: Make the entire API tree static
RDMA/efa: Mask access flags with the correct optional range
RDMA/cma: Fix unbalanced cm_id reference count during address resolve
RDMA/umem: Fix ib_umem_find_best_pgsz()
IB/mlx4: Fix leak in id_map_find_del
IB/opa_vnic: Spelling correction of 'erorr' to 'error'
IB/hfi1: Fix logical condition in msix_request_irq
RDMA/cm: Remove CM message structs
RDMA/cm: Use IBA functions for complex structure members
RDMA/cm: Use IBA functions for simple structure members
RDMA/cm: Use IBA functions for swapping get/set acessors
RDMA/cm: Use IBA functions for simple get/set acessors
RDMA/cm: Add SET/GET implementations to hide IBA wire format
RDMA/cm: Add accessors for CM_REQ transport_type
IB/mlx5: Return the administrative GUID if exists
RDMA/core: Ensure that rdma_user_mmap_entry_remove() is a fence
IB/mlx4: Fix memory leak in add_gid error flow
IB/mlx5: Expose RoCE accelerator counters
RDMA/mlx5: Set relaxed ordering when requested
RDMA/core: Add the core support field to METHOD_GET_CONTEXT
...
Convert infiniband to use the new pin_user_pages*() calls.
Also, revert earlier changes to Infiniband ODP that had it using
put_user_page(). ODP is "Case 3" in
Documentation/core-api/pin_user_pages.rst, which is to say, normal
get_user_pages() and put_page() is the API to use there.
The new pin_user_pages*() calls replace corresponding get_user_pages*()
calls, and set the FOLL_PIN flag. The FOLL_PIN flag requires that the
caller must return the pages via put_user_page*() calls, but infiniband
was already doing that as part of an earlier commit.
Link: http://lkml.kernel.org/r/20200107224558.2362728-14-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
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>
HPAGE_SHIFT is only defined on architectures that support hugepages:
drivers/infiniband/core/umem_odp.c: In function 'ib_umem_odp_get':
drivers/infiniband/core/umem_odp.c:245:26: error: 'HPAGE_SHIFT' undeclared (first use in this function); did you mean 'PAGE_SHIFT'?
Enclose this in an #ifdef.
Fixes: 9ff1b6466a ("IB/core: Fix ODP with IB_ACCESS_HUGETLB handling")
Link: https://lore.kernel.org/r/20200109084740.2872079-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
As VMAs for a given range might not be available as part of the
registration phase in ODP.
ib_init_umem_odp() considered the expected page shift value that was
previously set and initializes its internals accordingly.
If memory isn't backed by physical contiguous pages aligned to a hugepage
boundary an error will be set as part of the page fault flow and come back
to the user as some failed RDMA operation.
Fixes: 0008b84ea9 ("IB/umem: Add support to huge ODP")
Link: https://lore.kernel.org/r/20191222124649.52300-4-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The nr_pages argument of get_user_pages_remote() should always be in terms
of the system page size, not the MR page size. Use PAGE_SIZE instead of
umem_odp->page_shift.
Fixes: 403cd12e2c ("IB/umem: Add contiguous ODP support")
Link: https://lore.kernel.org/r/20191222124649.52300-3-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
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: ca748c39ea ("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>
invalidate_range() also obtains the umem_mutex which is being held at this
point, so if this path were was ever called it would deadlock. Thus
conclude the debugging never triggers and rework it into a simple WARN_ON
and leave things as they are.
While here add a note to explain how we could possibly get inconsistent
page pointers.
Link: https://lore.kernel.org/r/20191009160934.3143-16-jgg@ziepe.ca
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This fixes a race of the form:
CPU0 CPU1
mlx5_ib_invalidate_range() mlx5_ib_invalidate_range()
// This one actually makes npages == 0
ib_umem_odp_unmap_dma_pages()
if (npages == 0 && !dying)
// This one does nothing
ib_umem_odp_unmap_dma_pages()
if (npages == 0 && !dying)
dying = 1;
dying = 1;
schedule_work(&umem_odp->work);
// Double schedule of the same work
schedule_work(&umem_odp->work); // BOOM
npages and dying must be read and written under the umem_mutex lock.
Since whenever ib_umem_odp_unmap_dma_pages() is called mlx5 must also call
mlx5_ib_update_xlt, and both need to be done in the same locking region,
hoist the lock out of unmap.
This avoids an expensive double critical section in
mlx5_ib_invalidate_range().
Fixes: 81713d3788 ("IB/mlx5: Add implicit MR support")
Link: https://lore.kernel.org/r/20191001153821.23621-4-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This cycle mainly saw lots of bug fixes and clean up code across the core
code and several drivers, few new functional changes were made.
- Many cleanup and bug fixes for hns
- Various small bug fixes and cleanups in hfi1, mlx5, usnic, qed,
bnxt_re, efa
- Share the query_port code between all the iWarp drivers
- General rework and cleanup of the ODP MR umem code to fit better with
the mmu notifier get/put scheme
- Support rdma netlink in non init_net name spaces
- mlx5 support for XRC devx and DC ODP
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull RDMA subsystem updates from Jason Gunthorpe:
"This cycle mainly saw lots of bug fixes and clean up code across the
core code and several drivers, few new functional changes were made.
- Many cleanup and bug fixes for hns
- Various small bug fixes and cleanups in hfi1, mlx5, usnic, qed,
bnxt_re, efa
- Share the query_port code between all the iWarp drivers
- General rework and cleanup of the ODP MR umem code to fit better
with the mmu notifier get/put scheme
- Support rdma netlink in non init_net name spaces
- mlx5 support for XRC devx and DC ODP"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (99 commits)
RDMA: Fix double-free in srq creation error flow
RDMA/efa: Fix incorrect error print
IB/mlx5: Free mpi in mp_slave mode
IB/mlx5: Use the original address for the page during free_pages
RDMA/bnxt_re: Fix spelling mistake "missin_resp" -> "missing_resp"
RDMA/hns: Package operations of rq inline buffer into separate functions
RDMA/hns: Optimize cmd init and mode selection for hip08
IB/hfi1: Define variables as unsigned long to fix KASAN warning
IB/{rdmavt, hfi1, qib}: Add a counter for credit waits
IB/hfi1: Add traces for TID RDMA READ
RDMA/siw: Relax from kmap_atomic() use in TX path
IB/iser: Support up to 16MB data transfer in a single command
RDMA/siw: Fix page address mapping in TX path
RDMA: Fix goto target to release the allocated memory
RDMA/usnic: Avoid overly large buffers on stack
RDMA/odp: Add missing cast for 32 bit
RDMA/hns: Use devm_platform_ioremap_resource() to simplify code
Documentation/infiniband: update name of some functions
RDMA/cma: Fix false error message
RDMA/hns: Fix wrong assignment of qp_access_flags
...
length is a size_t which is unsigned int on 32 bit:
../drivers/infiniband/core/umem_odp.c: In function 'ib_init_umem_odp':
../include/linux/overflow.h:59:15: warning: comparison of distinct pointer types lacks a cast
59 | (void) (&__a == &__b); \
| ^~
../drivers/infiniband/core/umem_odp.c:220:7: note: in expansion of macro 'check_add_overflow'
Fixes: 204e3e5630 ("RDMA/odp: Check for overflow when computing the umem_odp end")
Link: https://lore.kernel.org/r/20190908080726.30017-1-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
At this point the ucontext is only being stored to access the ib_device,
so just store the ib_device directly instead. This is more natural and
logical as the umem has nothing to do with the ucontext.
Link: https://lore.kernel.org/r/20190806231548.25242-8-jgg@ziepe.ca
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This is a significant simplification, no extra list is kept per FD, and
the interval tree is now shared between all the ucontexts, reducing
overhead if there are multiple ucontexts active.
Link: https://lore.kernel.org/r/20190806231548.25242-7-jgg@ziepe.ca
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The callback function 'invalidate_range' is implemented in a driver so the
place for it is in the ib_device_ops structure and not in ib_ucontext.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Guy Levi <guyle@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Link: https://lore.kernel.org/r/20190819111710.18440-11-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
There is no specific need for these to be in the valloc space, let the
system decide automatically how to do the allocation.
Link: https://lore.kernel.org/r/20190819111710.18440-10-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Since the page size can be extended in the ODP case by IB_ACCESS_HUGETLB
the existing overflow checks done by ib_umem_get() are not
sufficient. Check for overflow again.
Further, remove the unchecked math from the inlines and just use the
precomputed value stored in the interval_tree_node.
Link: https://lore.kernel.org/r/20190819111710.18440-9-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Now that there are allocator APIs that return the ib_umem_odp directly
it should be freed through a umem_odp free'er as well.
Link: https://lore.kernel.org/r/20190819111710.18440-8-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This is the last creation API that is overloaded for both, there is very
little code sharing and a driver has to be specifically ready for a
umem_odp to be created to use the odp version.
Link: https://lore.kernel.org/r/20190819111710.18440-7-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The three paths to build the umem_odps are kind of muddled, they are:
- As a normal ib_mr umem
- As a child in an implicit ODP umem tree
- As the root of an implicit ODP umem tree
Only the first two are actually umem's, the last is an abuse.
The implicit case can only be triggered by explicit driver request, it
should never be co-mingled with the normal case. While we are here, make
sensible function names and add some comments to make this clearer.
Link: https://lore.kernel.org/r/20190819111710.18440-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This is done in two different places, consolidate all the post-allocation
initialization into a single function.
Link: https://lore.kernel.org/r/20190819111710.18440-5-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Implicit ODP umems are special, they don't have any page lists, they don't
exist in the interval tree and they are never DMA mapped.
Instead of trying to guess this based on a zero length use an explicit
flag.
Further, do not allow non-implicit umems to be 0 size.
Link: https://lore.kernel.org/r/20190819111710.18440-4-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Instead of intersecting a full interval, just iterate over every element
directly. This is faster and clearer.
Link: https://lore.kernel.org/r/20190819111710.18440-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
ODP is working with userspace VA's in the interval tree which always fit
into an unsigned long, so we can use the common code.
This comes at a cost of a 16 byte increase in ib_umem_odp struct size due
to storing the interval tree start/last in addition to the umem
addr/length. However these values were computed and are performance
critical for the interval lookup, so this seems like a worthwhile trade
off.
Removes 2k of .text from the kernel.
Link: https://lore.kernel.org/r/20190819111710.18440-2-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Once implicit MR is being called to be released by
ib_umem_notifier_release() its leaves were marked as "dying".
However, when dereg_mr()->mlx5_ib_free_implicit_mr()->mr_leaf_free() is
called, it skips running the mr_leaf_free_action (i.e. umem_odp->work)
when those leaves were marked as "dying".
As such ib_umem_release() for the leaves won't be called and their MRs
will be leaked as well.
When an application exits/killed without calling dereg_mr we might hit the
above flow.
This fatal scenario is reported by WARN_ON() upon
mlx5_ib_dealloc_ucontext() as ibcontext->per_mm_list is not empty, the
call trace can be seen below.
Originally the "dying" mark as part of ib_umem_notifier_release() was
introduced to prevent pagefault_mr() from returning a success response
once this happened. However, we already have today the completion
mechanism so no need for that in those flows any more. Even in case a
success response will be returned the firmware will not find the pages and
an error will be returned in the following call as a released mm will
cause ib_umem_odp_map_dma_pages() to permanently fail mmget_not_zero().
Fix the above issue by dropping the "dying" from the above flows. The
other flows that are using "dying" are still needed it for their
synchronization purposes.
WARNING: CPU: 1 PID: 7218 at
drivers/infiniband/hw/mlx5/main.c:2004
mlx5_ib_dealloc_ucontext+0x84/0x90 [mlx5_ib]
CPU: 1 PID: 7218 Comm: ibv_rc_pingpong Tainted: G E
5.2.0-rc6+ #13
Call Trace:
uverbs_destroy_ufile_hw+0xb5/0x120 [ib_uverbs]
ib_uverbs_close+0x1f/0x80 [ib_uverbs]
__fput+0xbe/0x250
task_work_run+0x88/0xa0
do_exit+0x2cb/0xc30
? __fput+0x14b/0x250
do_group_exit+0x39/0xb0
get_signal+0x191/0x920
? _raw_spin_unlock_bh+0xa/0x20
? inet_csk_accept+0x229/0x2f0
do_signal+0x36/0x5e0
? put_unused_fd+0x5b/0x70
? __sys_accept4+0x1a6/0x1e0
? inet_hash+0x35/0x40
? release_sock+0x43/0x90
? _raw_spin_unlock_bh+0xa/0x20
? inet_listen+0x9f/0x120
exit_to_usermode_loop+0x5c/0xc6
do_syscall_64+0x182/0x1b0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 81713d3788 ("IB/mlx5: Add implicit MR support")
Link: https://lore.kernel.org/r/20190805083010.21777-1-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The ib_dma_unmap_page() must match the length of the ib_dma_map_page(),
which is based on odp_shift. Otherwise iommu resources under this API
will not be properly freed.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
If invalidate_start returns with EAGAIN then the umem_rwsem needs to be
unlocked as no invalidate_end will be called.
Cc: <stable@vger.kernel.org>
Fixes: ca748c39ea ("RDMA/umem: Get rid of per_mm->notifier_count")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
For infiniband code that retains pages via get_user_pages*(), release
those pages via the new put_user_page(), or put_user_pages*(), instead of
put_page()
This is a tiny part of the second step of fixing the problem described in
[1]. The steps are:
1) Provide put_user_page*() routines, intended to be used for releasing
pages that were pinned via get_user_pages*().
2) Convert all of the call sites for get_user_pages*(), to invoke
put_user_page*(), instead of put_page(). This involves dozens of call
sites, and will take some time.
3) After (2) is complete, use get_user_pages*() and put_user_page*() to
implement tracking of these pages. This tracking will be separate from
the existing struct page refcounting.
4) Use the tracking and identification of these pages, to implement
special handling (especially in writeback paths) when the pages are
backed by a filesystem. Again, [1] provides details as to why that is
desirable.
[1] https://lwn.net/Articles/753027/ : "The Trouble with get_user_pages()"
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Tested-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This value has always been set to PAGE_SHIFT in the core code, the only
thing that does differently was the ODP path. Move the value into the ODP
struct and still use it for ODP, but change all the non-ODP things to just
use PAGE_SHIFT/PAGE_SIZE/PAGE_MASK directly.
Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Use the mmu_notifier_range_blockable() helper function instead of directly
dereferencing the range->blockable field. This is done to make it easier
to change the mmu_notifier range field.
This patch is the outcome of the following coccinelle patch:
%<-------------------------------------------------------------------
@@
identifier I1, FN;
@@
FN(..., struct mmu_notifier_range *I1, ...) {
<...
-I1->blockable
+mmu_notifier_range_blockable(I1)
...>
}
------------------------------------------------------------------->%
spatch --in-place --sp-file blockable.spatch --dir .
Link: http://lkml.kernel.org/r/20190326164747.24405-3-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The drivers i40iw and bnxt_re no longer dependent on the hugetlb flag. So
remove this flag from ib_umem structure.
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Combine contiguous regions of PAGE_SIZE pages into single scatter list
entry while building the scatter table for a umem. This minimizes the
number of the entries in the scatter list and reduces the DMA mapping
overhead, particularly with the IOMMU.
Set default max_seg_size in core for IB devices to 2G and do not combine
if we exceed this limit.
Also, purge npages in struct ib_umem as we now DMA map the umem SGL with
sg_nents and npage computation is not needed. Drivers should now be using
ib_umem_num_pages(), so fix the last stragglers.
Move npages tracking to ib_umem_odp as ODP drivers still need it.
Suggested-by: Jason Gunthorpe <jgg@ziepe.ca>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Adit Ranadive <aditr@vmware.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Tested-by: Gal Pressman <galpress@amazon.com>
Tested-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
No device supports ODP MR without an invalidate_range callback.
Warn on any any device which attempts to support ODP without supplying
this callback.
Then we can remove the checks for the callback within the code.
This stems from the discussion
https://www.spinics.net/lists/linux-rdma/msg76460.html
...which concluded this code was no longer necessary.
Acked-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The previous attempted bug fix overlooked the fact that
ib_umem_odp_map_dma_single_page() was doing a put_page() upon hitting an
error. So there was not really a bug there.
Therefore, this reverts the off-by-one change, but keeps the change to use
release_pages() in the error path.
Fixes: 75a3e6a3c1 ("RDMA/umem: minor bug fix in error handling path")
Suggested-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
1. Bug fix: fix an off by one error in the code that cleans up if it fails
to dma-map a page, after having done a get_user_pages_remote() on a
range of pages.
2. Refinement: for that same cleanup code, release_pages() is better than
put_page() in a loop.
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
It is possible that during a page fault handling, the process that owns
the MR is terminating. The indication for it is failure to get the
task_struct or take reference on the mm_struct. In this case just abort
the page-fault handler with error but without a warning to the kernel log.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
