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2019-06-20RDMA/odp: Do not leak dma maps when working with huge pagesJason Gunthorpe1-1/+2
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>
2019-06-18RDMA/odp: Fix missed unlock in non-blocking invalidate_startJason Gunthorpe1-5/+9
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: ca748c39ea3f ("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>
2019-05-27RDMA: Convert put_page() to put_user_page*()John Hubbard1-5/+5
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>
2019-05-21RDMA/umem: Move page_shift from ib_umem to ib_odp_umemJason Gunthorpe1-43/+36
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>
2019-05-14mm/mmu_notifier: convert user range->blockable to helper functionJérôme Glisse1-2/+3
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>
2019-05-06RDMA/umem: Remove hugetlb flagShiraz Saleem1-3/+0
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>
2019-04-08RDMA/umem: Combine contiguous PAGE_SIZE regions in SGEsShiraz Saleem1-2/+2
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>
2019-03-26IB/core: Ensure an invalidate_range callback on ODP MRIra Weiny1-10/+3
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>
2019-03-06RDMA/umem: Revert broken 'off by one' fixJohn Hubbard1-3/+6
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: 75a3e6a3c129 ("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>
2019-03-04RDMA/umem: minor bug fix in error handling pathJohn Hubbard1-3/+6
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>
2019-02-21IB/core: Abort page fault handler silently during owning process exitMoni Shoua1-1/+1
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>
2019-02-04Merge tag 'v5.0-rc5' into rdma.git for-nextJason Gunthorpe1-0/+3
Linux 5.0-rc5 Needed to merge the include/uapi changes so we have an up to date single-tree for these files. Patches already posted are also expected to need this for dependencies.
2019-01-25RDMA/umem: Add missing initialization of owning_mmArtemy Kovalyov1-0/+3
When allocating a umem leaf for implicit ODP MR during page fault the field owning_mm was not set. Initialize and take a reference on this field to avoid kernel panic when trying to access this field. BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 PGD 800000022dfed067 P4D 800000022dfed067 PUD 22dfcf067 PMD 0 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 634 Comm: kworker/u33:0 Not tainted 4.20.0-rc6+ #89 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 Workqueue: mlx5_ib_page_fault mlx5_ib_eqe_pf_action [mlx5_ib] RIP: 0010:ib_umem_odp_map_dma_pages+0xf3/0x710 [ib_core] Code: 45 c0 48 21 f3 48 89 75 b0 31 f6 4a 8d 04 33 48 89 45 a8 49 8b 44 24 60 48 8b 78 10 e8 66 16 a8 c5 49 8b 54 24 08 48 89 45 98 <8b> 42 58 85 c0 0f 84 8e 05 00 00 8d 48 01 48 8d 72 58 f0 0f b1 4a RSP: 0000:ffffb610813a7c20 EFLAGS: 00010202 RAX: ffff95ace6e8ac80 RBX: 0000000000000000 RCX: 000000000000000c RDX: 0000000000000000 RSI: 0000000000000850 RDI: ffff95aceaadae80 RBP: ffffb610813a7ce0 R08: 0000000000000000 R09: 0000000000080c77 R10: ffff95acfffdbd00 R11: 0000000000000000 R12: ffff95aceaa20a00 R13: 0000000000001000 R14: 0000000000001000 R15: 000000000000000c FS: 0000000000000000(0000) GS:ffff95acf7800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000058 CR3: 000000022c834001 CR4: 00000000001606f0 Call Trace: pagefault_single_data_segment+0x1df/0xc60 [mlx5_ib] mlx5_ib_eqe_pf_action+0x7bc/0xa70 [mlx5_ib] ? __switch_to+0xe1/0x470 process_one_work+0x174/0x390 worker_thread+0x4f/0x3e0 kthread+0x102/0x140 ? drain_workqueue+0x130/0x130 ? kthread_stop+0x110/0x110 ret_from_fork+0x1f/0x30 Fixes: f27a0d50a4bc ("RDMA/umem: Use umem->owning_mm inside ODP") Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Moni Shoua <monis@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-01-24IB/mlx5: Ranges in implicit ODP MR inherit its write accessMoni Shoua1-2/+3
A sub-range in ODP implicit MR should take its write permission from the MR and not be set always to allow. Fixes: d07d1d70ce1a ("IB/umem: Update on demand page (ODP) support") Signed-off-by: Moni Shoua <monis@mellanox.com> Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-01-24IB/core: Declare local functions 'static'Bart Van Assche1-1/+1
This patch avoids that sparse complains about missing function declarations. Fixes: f27a0d50a4bc ("RDMA/umem: Use umem->owning_mm inside ODP") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-12-28mm/mmu_notifier: use structure for invalidate_range_start/end callbackJérôme Glisse1-12/+8
Patch series "mmu notifier contextual informations", v2. This patchset adds contextual information, why an invalidation is happening, to mmu notifier callback. This is necessary for user of mmu notifier that wish to maintains their own data structure without having to add new fields to struct vm_area_struct (vma). For instance device can have they own page table that mirror the process address space. When a vma is unmap (munmap() syscall) the device driver can free the device page table for the range. Today we do not have any information on why a mmu notifier call back is happening and thus device driver have to assume that it is always an munmap(). This is inefficient at it means that it needs to re-allocate device page table on next page fault and rebuild the whole device driver data structure for the range. Other use case beside munmap() also exist, for instance it is pointless for device driver to invalidate the device page table when the invalidation is for the soft dirtyness tracking. Or device driver can optimize away mprotect() that change the page table permission access for the range. This patchset enables all this optimizations for device drivers. I do not include any of those in this series but another patchset I am posting will leverage this. The patchset is pretty simple from a code point of view. The first two patches consolidate all mmu notifier arguments into a struct so that it is easier to add/change arguments. The last patch adds the contextual information (munmap, protection, soft dirty, clear, ...). This patch (of 3): To avoid having to change many callback definition everytime we want to add a parameter use a structure to group all parameters for the mmu_notifier invalidate_range_start/end callback. No functional changes with this patch. [akpm@linux-foundation.org: fix drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c kerneldoc] Link: http://lkml.kernel.org/r/20181205053628.3210-2-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Jason Gunthorpe <jgg@mellanox.com> [infiniband] Cc: Matthew Wilcox <mawilcox@microsoft.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: Felix Kuehling <felix.kuehling@amd.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-10Merge branch 'mlx5-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linuxSaeed Mahameed1-2/+12
mlx5-next shared branch with rdma subtree to avoid mlx5 rdma v.s. netdev conflicts. Highlights: 1) RDMA ODP (On Demand Paging) improvements and moving ODP logic to mlx5 RDMA driver 2) Improved mlx5 core driver and device events handling and provided API for upper layers to subscribe to device events. 3) RDMA only code cleanup from mlx5 core 4) Add helper to get CQE opcode 5) Rework handling of port module events 6) shared mlx5_ifc.h updates to avoid conflicts Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2018-11-26IB/umem: Set correct address to the invalidation functionArtemy Kovalyov1-14/+6
The invalidate range was using PAGE_SIZE instead of the computed 'end', and had the wrong transformation of page_index due the weird construction. This can trigger during error unwind and would cause malfunction. Inline the code and correct the math. Fixes: 403cd12e2cf7 ("IB/umem: Add contiguous ODP support") Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Moni Shoua <monis@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-11-12IB/mlx5: Improve ODP debugging messagesMoni Shoua1-2/+12
Add and modify debug messages to ODP related error flows. In that context, return code EAGAIN is considered less severe and print level for it is set debug instead of warn. Signed-off-by: Moni Shoua <monis@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2018-09-21RDMA/umem: Avoid synchronize_srcu in the ODP MR destruction pathJason Gunthorpe1-2/+8
synchronize_rcu is slow enough that it should be avoided on the syscall path when user space is destroying MRs. After all the rework we can now trivially do this by having call_srcu kfree the per_mm. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21RDMA/umem: Handle a half-complete start/end sequenceJason Gunthorpe1-13/+26
mmu_notifier_unregister() can race between a invalidate_start/end and cause the invalidate_end to be skipped. This causes an imbalance in the locking, which lockdep complains about. This is not actually a bug, as we immediately kfree the memory holding the lock, but it simple enough to fix. Mark when the notifier is being destroyed and abort the start callback. This can be done under the lock we already obtained, and can re-purpose the invalidate_range test we already have. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21RDMA/umem: Get rid of per_mm->notifier_countJason Gunthorpe1-95/+18
This is intrinsically racy and the scheme is simply unnecessary. New MR registration can wait for any on going invalidation to fully complete. CPU0 CPU1 if (atomic_read()) if (atomic_dec_and_test() && !list_empty()) { /* not taken */ } list_add() Putting the new UMEM into some kind of purgatory until another invalidate rolls through.. Instead hold the read side of the umem_rwsem across the pair'd start/end and get rid of the racy 'deferred add' approach. Since all umem's in the rbt are always ready to go, also get rid of the mn_counters_active stuff. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21RDMA/umem: Use umem->owning_mm inside ODPJason Gunthorpe1-141/+160
Since ODP had a single struct mmu_notifier located in the ucontext it could only handle a single MM at a time, and this prevented it from using the new owning_mm system. With the prior rework it is now simple to let ODP track multiple MMs per ucontext, finish the job so that the per_mm is allocated on a mm by mm basis, and freed when the last umem is dropped from the ucontext. As a side effect the new saner locking removes the lockdep splat about nesting the umem_rwsem between mmu_notifier_unregister and ib_umem_odp_release. It also makes ODP work with multiple processes, across, fork, etc. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21RDMA/umem: Move all the ODP related stuff out of ucontext and into per_mmJason Gunthorpe1-59/+68
This is the first step to make ODP use the owning_mm that is now part of struct ib_umem. Each ODP umem is linked to a single per_mm structure, which in turn, is linked to a single mm, via the embedded mmu_notifier. This first patch introduces the structure and reworks eveything to use it. This also needs to introduce tgid into the ib_ucontext_per_mm, as get_user_pages_remote() requires the originating task for statistics tracking. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21RDMA/umem: Get rid of struct ib_umem.odp_dataJason Gunthorpe1-2/+1
This no longer has any use, we can use container_of to get to the umem_odp, and a simple flag to indicate if this is an odp MR. Remove the few remaining references to it. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21RDMA/umem: Make ib_umem_odp into a sub structure of ib_umemJason Gunthorpe1-49/+30
These two structures are linked together, use the container_of pattern instead of a double allocation to make the code simpler and easier to follow. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21RDMA/umem: Use ib_umem_odp in all function signatures connected to ODPJason Gunthorpe1-66/+73
All of these functions already require the ODP version of the umem struct, make this very clear by having the signature require it. This paves the way to using the container_of() pattern to link umem_odp and umem together. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-06RDMA/umem: Restore lockdep check while downgrading lockLeon Romanovsky1-6/+0
Lockdep engine handles correctly downgrade of locks and it simply incorrect to disable lockdep checks prior to calling mmu_notifier. Remove lockdep_off and ensure locks correctness. Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-08-22mm, oom: distinguish blockable mode for mmu notifiersMichal Hocko1-7/+26
There are several blockable mmu notifiers which might sleep in mmu_notifier_invalidate_range_start and that is a problem for the oom_reaper because it needs to guarantee a forward progress so it cannot depend on any sleepable locks. Currently we simply back off and mark an oom victim with blockable mmu notifiers as done after a short sleep. That can result in selecting a new oom victim prematurely because the previous one still hasn't torn its memory down yet. We can do much better though. Even if mmu notifiers use sleepable locks there is no reason to automatically assume those locks are held. Moreover majority of notifiers only care about a portion of the address space and there is absolutely zero reason to fail when we are unmapping an unrelated range. Many notifiers do really block and wait for HW which is harder to handle and we have to bail out though. This patch handles the low hanging fruit. __mmu_notifier_invalidate_range_start gets a blockable flag and callbacks are not allowed to sleep if the flag is set to false. This is achieved by using trylock instead of the sleepable lock for most callbacks and continue as long as we do not block down the call chain. I think we can improve that even further because there is a common pattern to do a range lookup first and then do something about that. The first part can be done without a sleeping lock in most cases AFAICS. The oom_reaper end then simply retries if there is at least one notifier which couldn't make any progress in !blockable mode. A retry loop is already implemented to wait for the mmap_sem and this is basically the same thing. The simplest way for driver developers to test this code path is to wrap userspace code which uses these notifiers into a memcg and set the hard limit to hit the oom. This can be done e.g. after the test faults in all the mmu notifier managed memory and set the hard limit to something really small. Then we are looking for a proper process tear down. [akpm@linux-foundation.org: coding style fixes] [akpm@linux-foundation.org: minor code simplification] Link: http://lkml.kernel.org/r/20180716115058.5559-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Christian König <christian.koenig@amd.com> # AMD notifiers Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx and umem_odp Reported-by: David Rientjes <rientjes@google.com> Cc: "David (ChunMing) Zhou" <David1.Zhou@amd.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: David Airlie <airlied@linux.ie> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Doug Ledford <dledford@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Mike Marciniszyn <mike.marciniszyn@intel.com> Cc: Dennis Dalessandro <dennis.dalessandro@intel.com> Cc: Sudeep Dutt <sudeep.dutt@intel.com> Cc: Ashutosh Dixit <ashutosh.dixit@intel.com> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Felix Kuehling <felix.kuehling@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-12treewide: Use array_size() in vzalloc()Kees Cook1-6/+10
The vzalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vzalloc(a * b) with: vzalloc(array_size(a, b)) as well as handling cases of: vzalloc(a * b * c) with: vzalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vzalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(char) * COUNT + COUNT , ...) | vzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vzalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vzalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vzalloc(C1 * C2 * C3, ...) | vzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vzalloc(C1 * C2, ...) | vzalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-10RDMA/umem: Avoid partial declaration of non-static functionLeon Romanovsky1-0/+72
The RDMA/umem uses generic RB-trees macros to generate various ib_umem access functions. The generation is performed with INTERVAL_TREE_DEFINE macro, which allows one of two modes: declare all functions as static or declare none of the function to be static. The second mode of operation produces the following sparse errors: drivers/infiniband/core/umem_rbtree.c:69:1: warning: symbol 'rbt_ib_umem_iter_first' was not declared. Should it be static? drivers/infiniband/core/umem_rbtree.c:69:1: warning: symbol 'rbt_ib_umem_iter_next' was not declared. Should it be static? Code relocation together with declaration of such functions to be "static" solves the issue. Because there is no need to have separate file for two functions, let's consolidate umem_rtree.c and umem_odp.c into one file. Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31IB/umem: update to new mmu_notifier semanticJérôme Glisse1-19/+0
Calls to mmu_notifier_invalidate_page() were replaced by calls to mmu_notifier_invalidate_range() and are now bracketed by calls to mmu_notifier_invalidate_range_start()/end() Remove now useless invalidate_page callback. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Tested-by: Leon Romanovsky <leonro@mellanox.com> Cc: linux-rdma@vger.kernel.org Cc: Artemy Kovalyov <artemyko@mellanox.com> Cc: Doug Ledford <dledford@redhat.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-01RDMA/umem: Fix missing mmap_sem in get umem ODP callLeon Romanovsky1-1/+5
Add mmap_sem lock around VMA inspection in ib_umem_odp_get(). Fixes: 0008b84ea9af ('IB/umem: Add support to huge ODP') Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Reviewed-by: Eli Cohen <eli@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-04-25IB/umem: Add support to huge ODPArtemy Kovalyov1-2/+17
Add IB_ACCESS_HUGETLB ib_reg_mr flag. Hugetlb region registered with this flag will use single translation entry per huge page. Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-04-25IB/umem: Add contiguous ODP supportArtemy Kovalyov1-19/+31
Currenlty ODP supports only regular MMU pages. Add ODP support for regions consisting of physically contiguous chunks of arbitrary order (huge pages for instance) to improve performance. Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-04-25IB: Replace ib_umem page_size by page_shiftArtemy Kovalyov1-6/+6
Size of pages are held by struct ib_umem in page_size field. It is better to store it as an exponent, because page size by nature is always power-of-two and used as a factor, divisor or ilog2's argument. The conversion of page_size to be page_shift allows to have portable code and avoid following error while compiling on ARM: ERROR: "__aeabi_uldivmod" [drivers/infiniband/core/ib_core.ko] undefined! CC: Selvin Xavier <selvin.xavier@broadcom.com> CC: Steve Wise <swise@chelsio.com> CC: Lijun Ou <oulijun@huawei.com> CC: Shiraz Saleem <shiraz.saleem@intel.com> CC: Adit Ranadive <aditr@vmware.com> CC: Dennis Dalessandro <dennis.dalessandro@intel.com> CC: Ram Amrani <Ram.Amrani@Cavium.com> Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Acked-by: Ram Amrani <Ram.Amrani@cavium.com> Acked-by: Shiraz Saleem <shiraz.saleem@intel.com> Acked-by: Selvin Xavier <selvin.xavier@broadcom.com> Acked-by: Selvin Xavier <selvin.xavier@broadcom.com> Acked-by: Adit Ranadive <aditr@vmware.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-03-02sched/headers: Prepare to move the get_task_struct()/put_task_struct() and related APIs from <linux/sched.h> to <linux/sched/task.h>Ingo Molnar1-0/+1
But first update usage sites with the new header dependency. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/mm.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/mm.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/mm.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. The APIs that are going to be moved first are: mm_alloc() __mmdrop() mmdrop() mmdrop_async_fn() mmdrop_async() mmget_not_zero() mmput() mmput_async() get_task_mm() mm_access() mm_release() Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-14IB/umem: Indicate that process is being terminatedArtemy Kovalyov1-2/+3
When process is killed while pagefault operation still in progress - function will fail. In this specific case we don't want any warnings in dmesg to avoid log analyzers false alerts. So we need distinct error code for this case. Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-02-14IB/umem: Update on demand page (ODP) supportArtemy Kovalyov1-9/+78
Currently ODP MR may explicitly register virtual address space area of limited length. This change allows MR to cover entire process virtual address space dynamicaly adding/removing translation entries to device MTT. Add following changes to support implicit MR: * Allow umem to be zero size to back-up implicit MR. * Add new function ib_alloc_odp_umem() to add virtual memory regions to implicit MR dynamically on demand. * Add new function rbt_ib_umem_lookup() to find dynamically added virtual memory regions. * Expose function rbt_ib_umem_for_each_in_range() to other modules and make it safe Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-12-14mm: add locked parameter to get_user_pages_remote()Lorenzo Stoakes1-1/+1
Patch series "mm: unexport __get_user_pages_unlocked()". This patch series continues the cleanup of get_user_pages*() functions taking advantage of the fact we can now pass gup_flags as we please. It firstly adds an additional 'locked' parameter to get_user_pages_remote() to allow for its callers to utilise VM_FAULT_RETRY functionality. This is necessary as the invocation of __get_user_pages_unlocked() in process_vm_rw_single_vec() makes use of this and no other existing higher level function would allow it to do so. Secondly existing callers of __get_user_pages_unlocked() are replaced with the appropriate higher-level replacement - get_user_pages_unlocked() if the current task and memory descriptor are referenced, or get_user_pages_remote() if other task/memory descriptors are referenced (having acquiring mmap_sem.) This patch (of 2): Add a int *locked parameter to get_user_pages_remote() to allow VM_FAULT_RETRY faulting behaviour similar to get_user_pages_[un]locked(). Taking into account the previous adjustments to get_user_pages*() functions allowing for the passing of gup_flags, we are now in a position where __get_user_pages_unlocked() need only be exported for his ability to allow VM_FAULT_RETRY behaviour, this adjustment allows us to subsequently unexport __get_user_pages_unlocked() as well as allowing for future flexibility in the use of get_user_pages_remote(). [sfr@canb.auug.org.au: merge fix for get_user_pages_remote API change] Link: http://lkml.kernel.org/r/20161122210511.024ec341@canb.auug.org.au Link: http://lkml.kernel.org/r/20161027095141.2569-2-lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Jan Kara <jack@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-19mm: replace get_user_pages_remote() write/force parameters with gup_flagsLorenzo Stoakes1-2/+5
This removes the 'write' and 'force' from get_user_pages_remote() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-16mm/gup: Introduce get_user_pages_remote()Dave Hansen1-4/+4
For protection keys, we need to understand whether protections should be enforced in software or not. In general, we enforce protections when working on our own task, but not when on others. We call these "current" and "remote" operations. This patch introduces a new get_user_pages() variant: get_user_pages_remote() Which is a replacement for when get_user_pages() is called on non-current tsk/mm. We also introduce a new gup flag: FOLL_REMOTE which can be used for the "__" gup variants to get this new behavior. The uprobes is_trap_at_addr() location holds mmap_sem and calls get_user_pages(current->mm) on an instruction address. This makes it a pretty unique gup caller. Being an instruction access and also really originating from the kernel (vs. the app), I opted to consider this a 'remote' access where protection keys will not be enforced. Without protection keys, this patch should not change any behavior. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: jack@suse.cz Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210154.3F0E51EA@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-24IB/core: constify mmu_notifier_ops structuresJulia Lawall1-1/+1
This mmu_notifier_ops structure is never modified, so declare it as const, like the other mmu_notifier_ops structures. Done with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Reviewed-by: Haggai Eran <haggaie@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2015-05-05IB/core: dma unmap optimizationsGuy Shapiro1-2/+3
While unmapping an ODP writable page, the dirty bit of the page is set. In order to do so, the head of the compound page is found. Currently, the compound head is found even on non-writable pages, where it is never used, leading to unnecessary cpu barrier that impacts performance. This patch moves the search for the compound head to be done only when needed. Signed-off-by: Guy Shapiro <guysh@mellanox.com> Acked-by: Shachar Raindel <raindel@mellanox.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2015-05-05IB/core: dma map/unmap locking optimizationsGuy Shapiro1-5/+4
Currently, while mapping or unmapping pages for ODP, the umem mutex is locked and unlocked once for each page. Such lock/unlock operation take few tens to hundreds of nsecs. This makes a significant impact when mapping or unmapping few MBs of memory. To avoid this, the mutex should be locked only once per operation, and not per page. Signed-off-by: Guy Shapiro <guysh@mellanox.com> Acked-by: Shachar Raindel <raindel@mellanox.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2015-02-17IB/core: Properly handle registration of on-demand paging MRs after deregHaggai Eran1-1/+2
When the last on-demand paging MR is released the notifier count is left non-zero so that concurrent page faults will have to abort. If a new MR is then registered, the counter is reset. However, the decision is made to put the new MR in the list waiting for the notifier count to reach zero, before the counter is reset. An invalidation or another MR registration can release the MR to handle page faults, but without such an event the MR can wait forever. The patch fixes this issue by adding a check whether the MR is the first on-demand paging MR when deciding whether it is ready to handle page faults. If it is the first MR, we know that there are no mmu notifiers running in parallel to the registration. Fixes: 882214e2b128 ("IB/core: Implement support for MMU notifiers regarding on demand paging regions") Signed-off-by: Haggai Eran <haggaie@mellanox.com> Signed-off-by: Shachar Raindel <raindel@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2014-12-15IB/core: Implement support for MMU notifiers regarding on demand paging regionsHaggai Eran1-10/+369
* Add an interval tree implementation for ODP umems. Create an interval tree for each ucontext (including a count of the number of ODP MRs in this context, semaphore, etc.), and register ODP umems in the interval tree. * Add MMU notifiers handling functions, using the interval tree to notify only the relevant umems and underlying MRs. * Register to receive MMU notifier events from the MM subsystem upon ODP MR registration (and unregister accordingly). * Add a completion object to synchronize the destruction of ODP umems. * Add mechanism to abort page faults when there's a concurrent invalidation. The way we synchronize between concurrent invalidations and page faults is by keeping a counter of currently running invalidations, and a sequence number that is incremented whenever an invalidation is caught. The page fault code checks the counter and also verifies that the sequence number hasn't progressed before it updates the umem's page tables. This is similar to what the kvm module does. In order to prevent the case where we register a umem in the middle of an ongoing notifier, we also keep a per ucontext counter of the total number of active mmu notifiers. We only enable new umems when all the running notifiers complete. Signed-off-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Shachar Raindel <raindel@mellanox.com> Signed-off-by: Haggai Eran <haggaie@mellanox.com> Signed-off-by: Yuval Dagan <yuvalda@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2014-12-15IB/core: Add support for on demand paging regionsShachar Raindel1-0/+309
* Extend the umem struct to keep the ODP related data. * Allocate and initialize the ODP related information in the umem (page_list, dma_list) and freeing as needed in the end of the run. * Store a reference to the process PID struct in the ucontext. Used to safely obtain the task_struct and the mm during fault handling, without preventing the task destruction if needed. * Add 2 helper functions: ib_umem_odp_map_dma_pages and ib_umem_odp_unmap_dma_pages. These functions get the DMA addresses of specific pages of the umem (and, currently, pin them). * Support for page faults only - IB core will keep the reference on the pages used and call put_page when freeing an ODP umem area. Invalidations support will be added in a later patch. Signed-off-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Shachar Raindel <raindel@mellanox.com> Signed-off-by: Haggai Eran <haggaie@mellanox.com> Signed-off-by: Majd Dibbiny <majd@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
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