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![Alistair Popple](/assets/img/avatar_default.png)
There are two main use cases for mmu notifiers. One is by KVM which uses mmu_notifier_invalidate_range_start()/end() to manage a software TLB. The other is to manage hardware TLBs which need to use the invalidate_range() callback because HW can establish new TLB entries at any time. Hence using start/end() can lead to memory corruption as these callbacks happen too soon/late during page unmap. mmu notifier users should therefore either use the start()/end() callbacks or the invalidate_range() callbacks. To make this usage clearer rename the invalidate_range() callback to arch_invalidate_secondary_tlbs() and update documention. Link: https://lkml.kernel.org/r/6f77248cd25545c8020a54b4e567e8b72be4dca1.1690292440.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Andrew Donnellan <ajd@linux.ibm.com> Cc: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com> Cc: Frederic Barrat <fbarrat@linux.ibm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Nicolin Chen <nicolinc@nvidia.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Sean Christopherson <seanjc@google.com> Cc: SeongJae Park <sj@kernel.org> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: Will Deacon <will@kernel.org> Cc: Zhi Wang <zhi.wang.linux@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
697 lines
23 KiB
C
697 lines
23 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_MMU_NOTIFIER_H
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#define _LINUX_MMU_NOTIFIER_H
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#include <linux/list.h>
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#include <linux/spinlock.h>
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#include <linux/mm_types.h>
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#include <linux/mmap_lock.h>
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#include <linux/srcu.h>
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#include <linux/interval_tree.h>
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struct mmu_notifier_subscriptions;
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struct mmu_notifier;
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struct mmu_notifier_range;
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struct mmu_interval_notifier;
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/**
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* enum mmu_notifier_event - reason for the mmu notifier callback
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* @MMU_NOTIFY_UNMAP: either munmap() that unmap the range or a mremap() that
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* move the range
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*
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* @MMU_NOTIFY_CLEAR: clear page table entry (many reasons for this like
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* madvise() or replacing a page by another one, ...).
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*
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* @MMU_NOTIFY_PROTECTION_VMA: update is due to protection change for the range
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* ie using the vma access permission (vm_page_prot) to update the whole range
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* is enough no need to inspect changes to the CPU page table (mprotect()
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* syscall)
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*
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* @MMU_NOTIFY_PROTECTION_PAGE: update is due to change in read/write flag for
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* pages in the range so to mirror those changes the user must inspect the CPU
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* page table (from the end callback).
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*
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* @MMU_NOTIFY_SOFT_DIRTY: soft dirty accounting (still same page and same
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* access flags). User should soft dirty the page in the end callback to make
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* sure that anyone relying on soft dirtiness catch pages that might be written
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* through non CPU mappings.
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*
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* @MMU_NOTIFY_RELEASE: used during mmu_interval_notifier invalidate to signal
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* that the mm refcount is zero and the range is no longer accessible.
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*
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* @MMU_NOTIFY_MIGRATE: used during migrate_vma_collect() invalidate to signal
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* a device driver to possibly ignore the invalidation if the
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* owner field matches the driver's device private pgmap owner.
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*
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* @MMU_NOTIFY_EXCLUSIVE: to signal a device driver that the device will no
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* longer have exclusive access to the page. When sent during creation of an
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* exclusive range the owner will be initialised to the value provided by the
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* caller of make_device_exclusive_range(), otherwise the owner will be NULL.
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*/
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enum mmu_notifier_event {
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MMU_NOTIFY_UNMAP = 0,
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MMU_NOTIFY_CLEAR,
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MMU_NOTIFY_PROTECTION_VMA,
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MMU_NOTIFY_PROTECTION_PAGE,
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MMU_NOTIFY_SOFT_DIRTY,
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MMU_NOTIFY_RELEASE,
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MMU_NOTIFY_MIGRATE,
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MMU_NOTIFY_EXCLUSIVE,
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};
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#define MMU_NOTIFIER_RANGE_BLOCKABLE (1 << 0)
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struct mmu_notifier_ops {
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/*
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* Called either by mmu_notifier_unregister or when the mm is
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* being destroyed by exit_mmap, always before all pages are
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* freed. This can run concurrently with other mmu notifier
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* methods (the ones invoked outside the mm context) and it
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* should tear down all secondary mmu mappings and freeze the
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* secondary mmu. If this method isn't implemented you've to
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* be sure that nothing could possibly write to the pages
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* through the secondary mmu by the time the last thread with
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* tsk->mm == mm exits.
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*
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* As side note: the pages freed after ->release returns could
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* be immediately reallocated by the gart at an alias physical
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* address with a different cache model, so if ->release isn't
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* implemented because all _software_ driven memory accesses
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* through the secondary mmu are terminated by the time the
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* last thread of this mm quits, you've also to be sure that
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* speculative _hardware_ operations can't allocate dirty
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* cachelines in the cpu that could not be snooped and made
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* coherent with the other read and write operations happening
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* through the gart alias address, so leading to memory
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* corruption.
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*/
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void (*release)(struct mmu_notifier *subscription,
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struct mm_struct *mm);
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/*
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* clear_flush_young is called after the VM is
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* test-and-clearing the young/accessed bitflag in the
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* pte. This way the VM will provide proper aging to the
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* accesses to the page through the secondary MMUs and not
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* only to the ones through the Linux pte.
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* Start-end is necessary in case the secondary MMU is mapping the page
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* at a smaller granularity than the primary MMU.
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*/
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int (*clear_flush_young)(struct mmu_notifier *subscription,
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struct mm_struct *mm,
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unsigned long start,
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unsigned long end);
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/*
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* clear_young is a lightweight version of clear_flush_young. Like the
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* latter, it is supposed to test-and-clear the young/accessed bitflag
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* in the secondary pte, but it may omit flushing the secondary tlb.
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*/
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int (*clear_young)(struct mmu_notifier *subscription,
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struct mm_struct *mm,
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unsigned long start,
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unsigned long end);
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/*
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* test_young is called to check the young/accessed bitflag in
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* the secondary pte. This is used to know if the page is
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* frequently used without actually clearing the flag or tearing
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* down the secondary mapping on the page.
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*/
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int (*test_young)(struct mmu_notifier *subscription,
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struct mm_struct *mm,
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unsigned long address);
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/*
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* change_pte is called in cases that pte mapping to page is changed:
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* for example, when ksm remaps pte to point to a new shared page.
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*/
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void (*change_pte)(struct mmu_notifier *subscription,
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struct mm_struct *mm,
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unsigned long address,
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pte_t pte);
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/*
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* invalidate_range_start() and invalidate_range_end() must be
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* paired and are called only when the mmap_lock and/or the
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* locks protecting the reverse maps are held. If the subsystem
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* can't guarantee that no additional references are taken to
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* the pages in the range, it has to implement the
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* invalidate_range() notifier to remove any references taken
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* after invalidate_range_start().
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*
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* Invalidation of multiple concurrent ranges may be
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* optionally permitted by the driver. Either way the
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* establishment of sptes is forbidden in the range passed to
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* invalidate_range_begin/end for the whole duration of the
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* invalidate_range_begin/end critical section.
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*
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* invalidate_range_start() is called when all pages in the
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* range are still mapped and have at least a refcount of one.
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*
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* invalidate_range_end() is called when all pages in the
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* range have been unmapped and the pages have been freed by
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* the VM.
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*
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* The VM will remove the page table entries and potentially
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* the page between invalidate_range_start() and
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* invalidate_range_end(). If the page must not be freed
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* because of pending I/O or other circumstances then the
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* invalidate_range_start() callback (or the initial mapping
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* by the driver) must make sure that the refcount is kept
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* elevated.
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*
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* If the driver increases the refcount when the pages are
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* initially mapped into an address space then either
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* invalidate_range_start() or invalidate_range_end() may
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* decrease the refcount. If the refcount is decreased on
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* invalidate_range_start() then the VM can free pages as page
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* table entries are removed. If the refcount is only
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* dropped on invalidate_range_end() then the driver itself
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* will drop the last refcount but it must take care to flush
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* any secondary tlb before doing the final free on the
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* page. Pages will no longer be referenced by the linux
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* address space but may still be referenced by sptes until
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* the last refcount is dropped.
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*
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* If blockable argument is set to false then the callback cannot
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* sleep and has to return with -EAGAIN if sleeping would be required.
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* 0 should be returned otherwise. Please note that notifiers that can
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* fail invalidate_range_start are not allowed to implement
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* invalidate_range_end, as there is no mechanism for informing the
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* notifier that its start failed.
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*/
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int (*invalidate_range_start)(struct mmu_notifier *subscription,
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const struct mmu_notifier_range *range);
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void (*invalidate_range_end)(struct mmu_notifier *subscription,
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const struct mmu_notifier_range *range);
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/*
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* arch_invalidate_secondary_tlbs() is used to manage a non-CPU TLB
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* which shares page-tables with the CPU. The
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* invalidate_range_start()/end() callbacks should not be implemented as
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* invalidate_secondary_tlbs() already catches the points in time when
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* an external TLB needs to be flushed.
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*
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* This requires arch_invalidate_secondary_tlbs() to be called while
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* holding the ptl spin-lock and therefore this callback is not allowed
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* to sleep.
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*
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* This is called by architecture code whenever invalidating a TLB
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* entry. It is assumed that any secondary TLB has the same rules for
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* when invalidations are required. If this is not the case architecture
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* code will need to call this explicitly when required for secondary
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* TLB invalidation.
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*/
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void (*arch_invalidate_secondary_tlbs)(
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struct mmu_notifier *subscription,
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struct mm_struct *mm,
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unsigned long start,
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unsigned long end);
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/*
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* These callbacks are used with the get/put interface to manage the
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* lifetime of the mmu_notifier memory. alloc_notifier() returns a new
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* notifier for use with the mm.
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*
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* free_notifier() is only called after the mmu_notifier has been
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* fully put, calls to any ops callback are prevented and no ops
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* callbacks are currently running. It is called from a SRCU callback
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* and cannot sleep.
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*/
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struct mmu_notifier *(*alloc_notifier)(struct mm_struct *mm);
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void (*free_notifier)(struct mmu_notifier *subscription);
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};
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/*
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* The notifier chains are protected by mmap_lock and/or the reverse map
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* semaphores. Notifier chains are only changed when all reverse maps and
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* the mmap_lock locks are taken.
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*
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* Therefore notifier chains can only be traversed when either
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*
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* 1. mmap_lock is held.
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* 2. One of the reverse map locks is held (i_mmap_rwsem or anon_vma->rwsem).
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* 3. No other concurrent thread can access the list (release)
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*/
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struct mmu_notifier {
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struct hlist_node hlist;
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const struct mmu_notifier_ops *ops;
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struct mm_struct *mm;
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struct rcu_head rcu;
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unsigned int users;
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};
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/**
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* struct mmu_interval_notifier_ops
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* @invalidate: Upon return the caller must stop using any SPTEs within this
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* range. This function can sleep. Return false only if sleeping
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* was required but mmu_notifier_range_blockable(range) is false.
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*/
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struct mmu_interval_notifier_ops {
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bool (*invalidate)(struct mmu_interval_notifier *interval_sub,
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const struct mmu_notifier_range *range,
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unsigned long cur_seq);
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};
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struct mmu_interval_notifier {
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struct interval_tree_node interval_tree;
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const struct mmu_interval_notifier_ops *ops;
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struct mm_struct *mm;
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struct hlist_node deferred_item;
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unsigned long invalidate_seq;
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};
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#ifdef CONFIG_MMU_NOTIFIER
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#ifdef CONFIG_LOCKDEP
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extern struct lockdep_map __mmu_notifier_invalidate_range_start_map;
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#endif
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struct mmu_notifier_range {
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struct mm_struct *mm;
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unsigned long start;
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unsigned long end;
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unsigned flags;
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enum mmu_notifier_event event;
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void *owner;
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};
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static inline int mm_has_notifiers(struct mm_struct *mm)
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{
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return unlikely(mm->notifier_subscriptions);
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}
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struct mmu_notifier *mmu_notifier_get_locked(const struct mmu_notifier_ops *ops,
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struct mm_struct *mm);
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static inline struct mmu_notifier *
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mmu_notifier_get(const struct mmu_notifier_ops *ops, struct mm_struct *mm)
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{
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struct mmu_notifier *ret;
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mmap_write_lock(mm);
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ret = mmu_notifier_get_locked(ops, mm);
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mmap_write_unlock(mm);
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return ret;
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}
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void mmu_notifier_put(struct mmu_notifier *subscription);
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void mmu_notifier_synchronize(void);
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extern int mmu_notifier_register(struct mmu_notifier *subscription,
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struct mm_struct *mm);
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extern int __mmu_notifier_register(struct mmu_notifier *subscription,
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struct mm_struct *mm);
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extern void mmu_notifier_unregister(struct mmu_notifier *subscription,
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struct mm_struct *mm);
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unsigned long
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mmu_interval_read_begin(struct mmu_interval_notifier *interval_sub);
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int mmu_interval_notifier_insert(struct mmu_interval_notifier *interval_sub,
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struct mm_struct *mm, unsigned long start,
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unsigned long length,
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const struct mmu_interval_notifier_ops *ops);
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int mmu_interval_notifier_insert_locked(
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struct mmu_interval_notifier *interval_sub, struct mm_struct *mm,
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unsigned long start, unsigned long length,
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const struct mmu_interval_notifier_ops *ops);
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void mmu_interval_notifier_remove(struct mmu_interval_notifier *interval_sub);
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/**
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* mmu_interval_set_seq - Save the invalidation sequence
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* @interval_sub - The subscription passed to invalidate
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* @cur_seq - The cur_seq passed to the invalidate() callback
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*
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* This must be called unconditionally from the invalidate callback of a
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* struct mmu_interval_notifier_ops under the same lock that is used to call
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* mmu_interval_read_retry(). It updates the sequence number for later use by
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* mmu_interval_read_retry(). The provided cur_seq will always be odd.
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*
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* If the caller does not call mmu_interval_read_begin() or
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* mmu_interval_read_retry() then this call is not required.
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*/
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static inline void
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mmu_interval_set_seq(struct mmu_interval_notifier *interval_sub,
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unsigned long cur_seq)
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{
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WRITE_ONCE(interval_sub->invalidate_seq, cur_seq);
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}
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/**
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* mmu_interval_read_retry - End a read side critical section against a VA range
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* interval_sub: The subscription
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* seq: The return of the paired mmu_interval_read_begin()
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*
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* This MUST be called under a user provided lock that is also held
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* unconditionally by op->invalidate() when it calls mmu_interval_set_seq().
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*
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* Each call should be paired with a single mmu_interval_read_begin() and
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* should be used to conclude the read side.
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*
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* Returns true if an invalidation collided with this critical section, and
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* the caller should retry.
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*/
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static inline bool
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mmu_interval_read_retry(struct mmu_interval_notifier *interval_sub,
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unsigned long seq)
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{
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return interval_sub->invalidate_seq != seq;
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}
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/**
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* mmu_interval_check_retry - Test if a collision has occurred
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* interval_sub: The subscription
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* seq: The return of the matching mmu_interval_read_begin()
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*
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* This can be used in the critical section between mmu_interval_read_begin()
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* and mmu_interval_read_retry(). A return of true indicates an invalidation
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* has collided with this critical region and a future
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* mmu_interval_read_retry() will return true.
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*
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* False is not reliable and only suggests a collision may not have
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* occurred. It can be called many times and does not have to hold the user
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* provided lock.
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*
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* This call can be used as part of loops and other expensive operations to
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* expedite a retry.
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*/
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static inline bool
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mmu_interval_check_retry(struct mmu_interval_notifier *interval_sub,
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unsigned long seq)
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{
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/* Pairs with the WRITE_ONCE in mmu_interval_set_seq() */
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return READ_ONCE(interval_sub->invalidate_seq) != seq;
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}
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extern void __mmu_notifier_subscriptions_destroy(struct mm_struct *mm);
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extern void __mmu_notifier_release(struct mm_struct *mm);
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extern int __mmu_notifier_clear_flush_young(struct mm_struct *mm,
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unsigned long start,
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unsigned long end);
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extern int __mmu_notifier_clear_young(struct mm_struct *mm,
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unsigned long start,
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unsigned long end);
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extern int __mmu_notifier_test_young(struct mm_struct *mm,
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unsigned long address);
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extern void __mmu_notifier_change_pte(struct mm_struct *mm,
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unsigned long address, pte_t pte);
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extern int __mmu_notifier_invalidate_range_start(struct mmu_notifier_range *r);
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extern void __mmu_notifier_invalidate_range_end(struct mmu_notifier_range *r);
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extern void __mmu_notifier_arch_invalidate_secondary_tlbs(struct mm_struct *mm,
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unsigned long start, unsigned long end);
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extern bool
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mmu_notifier_range_update_to_read_only(const struct mmu_notifier_range *range);
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static inline bool
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mmu_notifier_range_blockable(const struct mmu_notifier_range *range)
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{
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return (range->flags & MMU_NOTIFIER_RANGE_BLOCKABLE);
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}
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static inline void mmu_notifier_release(struct mm_struct *mm)
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{
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if (mm_has_notifiers(mm))
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__mmu_notifier_release(mm);
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}
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static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm,
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unsigned long start,
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unsigned long end)
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{
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if (mm_has_notifiers(mm))
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return __mmu_notifier_clear_flush_young(mm, start, end);
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return 0;
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}
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static inline int mmu_notifier_clear_young(struct mm_struct *mm,
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unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
if (mm_has_notifiers(mm))
|
|
return __mmu_notifier_clear_young(mm, start, end);
|
|
return 0;
|
|
}
|
|
|
|
static inline int mmu_notifier_test_young(struct mm_struct *mm,
|
|
unsigned long address)
|
|
{
|
|
if (mm_has_notifiers(mm))
|
|
return __mmu_notifier_test_young(mm, address);
|
|
return 0;
|
|
}
|
|
|
|
static inline void mmu_notifier_change_pte(struct mm_struct *mm,
|
|
unsigned long address, pte_t pte)
|
|
{
|
|
if (mm_has_notifiers(mm))
|
|
__mmu_notifier_change_pte(mm, address, pte);
|
|
}
|
|
|
|
static inline void
|
|
mmu_notifier_invalidate_range_start(struct mmu_notifier_range *range)
|
|
{
|
|
might_sleep();
|
|
|
|
lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
|
|
if (mm_has_notifiers(range->mm)) {
|
|
range->flags |= MMU_NOTIFIER_RANGE_BLOCKABLE;
|
|
__mmu_notifier_invalidate_range_start(range);
|
|
}
|
|
lock_map_release(&__mmu_notifier_invalidate_range_start_map);
|
|
}
|
|
|
|
static inline int
|
|
mmu_notifier_invalidate_range_start_nonblock(struct mmu_notifier_range *range)
|
|
{
|
|
int ret = 0;
|
|
|
|
lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
|
|
if (mm_has_notifiers(range->mm)) {
|
|
range->flags &= ~MMU_NOTIFIER_RANGE_BLOCKABLE;
|
|
ret = __mmu_notifier_invalidate_range_start(range);
|
|
}
|
|
lock_map_release(&__mmu_notifier_invalidate_range_start_map);
|
|
return ret;
|
|
}
|
|
|
|
static inline void
|
|
mmu_notifier_invalidate_range_end(struct mmu_notifier_range *range)
|
|
{
|
|
if (mmu_notifier_range_blockable(range))
|
|
might_sleep();
|
|
|
|
if (mm_has_notifiers(range->mm))
|
|
__mmu_notifier_invalidate_range_end(range);
|
|
}
|
|
|
|
static inline void mmu_notifier_arch_invalidate_secondary_tlbs(struct mm_struct *mm,
|
|
unsigned long start, unsigned long end)
|
|
{
|
|
if (mm_has_notifiers(mm))
|
|
__mmu_notifier_arch_invalidate_secondary_tlbs(mm, start, end);
|
|
}
|
|
|
|
static inline void mmu_notifier_subscriptions_init(struct mm_struct *mm)
|
|
{
|
|
mm->notifier_subscriptions = NULL;
|
|
}
|
|
|
|
static inline void mmu_notifier_subscriptions_destroy(struct mm_struct *mm)
|
|
{
|
|
if (mm_has_notifiers(mm))
|
|
__mmu_notifier_subscriptions_destroy(mm);
|
|
}
|
|
|
|
|
|
static inline void mmu_notifier_range_init(struct mmu_notifier_range *range,
|
|
enum mmu_notifier_event event,
|
|
unsigned flags,
|
|
struct mm_struct *mm,
|
|
unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
range->event = event;
|
|
range->mm = mm;
|
|
range->start = start;
|
|
range->end = end;
|
|
range->flags = flags;
|
|
}
|
|
|
|
static inline void mmu_notifier_range_init_owner(
|
|
struct mmu_notifier_range *range,
|
|
enum mmu_notifier_event event, unsigned int flags,
|
|
struct mm_struct *mm, unsigned long start,
|
|
unsigned long end, void *owner)
|
|
{
|
|
mmu_notifier_range_init(range, event, flags, mm, start, end);
|
|
range->owner = owner;
|
|
}
|
|
|
|
#define ptep_clear_flush_young_notify(__vma, __address, __ptep) \
|
|
({ \
|
|
int __young; \
|
|
struct vm_area_struct *___vma = __vma; \
|
|
unsigned long ___address = __address; \
|
|
__young = ptep_clear_flush_young(___vma, ___address, __ptep); \
|
|
__young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \
|
|
___address, \
|
|
___address + \
|
|
PAGE_SIZE); \
|
|
__young; \
|
|
})
|
|
|
|
#define pmdp_clear_flush_young_notify(__vma, __address, __pmdp) \
|
|
({ \
|
|
int __young; \
|
|
struct vm_area_struct *___vma = __vma; \
|
|
unsigned long ___address = __address; \
|
|
__young = pmdp_clear_flush_young(___vma, ___address, __pmdp); \
|
|
__young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \
|
|
___address, \
|
|
___address + \
|
|
PMD_SIZE); \
|
|
__young; \
|
|
})
|
|
|
|
#define ptep_clear_young_notify(__vma, __address, __ptep) \
|
|
({ \
|
|
int __young; \
|
|
struct vm_area_struct *___vma = __vma; \
|
|
unsigned long ___address = __address; \
|
|
__young = ptep_test_and_clear_young(___vma, ___address, __ptep);\
|
|
__young |= mmu_notifier_clear_young(___vma->vm_mm, ___address, \
|
|
___address + PAGE_SIZE); \
|
|
__young; \
|
|
})
|
|
|
|
#define pmdp_clear_young_notify(__vma, __address, __pmdp) \
|
|
({ \
|
|
int __young; \
|
|
struct vm_area_struct *___vma = __vma; \
|
|
unsigned long ___address = __address; \
|
|
__young = pmdp_test_and_clear_young(___vma, ___address, __pmdp);\
|
|
__young |= mmu_notifier_clear_young(___vma->vm_mm, ___address, \
|
|
___address + PMD_SIZE); \
|
|
__young; \
|
|
})
|
|
|
|
/*
|
|
* set_pte_at_notify() sets the pte _after_ running the notifier.
|
|
* This is safe to start by updating the secondary MMUs, because the primary MMU
|
|
* pte invalidate must have already happened with a ptep_clear_flush() before
|
|
* set_pte_at_notify() has been invoked. Updating the secondary MMUs first is
|
|
* required when we change both the protection of the mapping from read-only to
|
|
* read-write and the pfn (like during copy on write page faults). Otherwise the
|
|
* old page would remain mapped readonly in the secondary MMUs after the new
|
|
* page is already writable by some CPU through the primary MMU.
|
|
*/
|
|
#define set_pte_at_notify(__mm, __address, __ptep, __pte) \
|
|
({ \
|
|
struct mm_struct *___mm = __mm; \
|
|
unsigned long ___address = __address; \
|
|
pte_t ___pte = __pte; \
|
|
\
|
|
mmu_notifier_change_pte(___mm, ___address, ___pte); \
|
|
set_pte_at(___mm, ___address, __ptep, ___pte); \
|
|
})
|
|
|
|
#else /* CONFIG_MMU_NOTIFIER */
|
|
|
|
struct mmu_notifier_range {
|
|
unsigned long start;
|
|
unsigned long end;
|
|
};
|
|
|
|
static inline void _mmu_notifier_range_init(struct mmu_notifier_range *range,
|
|
unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
range->start = start;
|
|
range->end = end;
|
|
}
|
|
|
|
#define mmu_notifier_range_init(range,event,flags,mm,start,end) \
|
|
_mmu_notifier_range_init(range, start, end)
|
|
#define mmu_notifier_range_init_owner(range, event, flags, mm, start, \
|
|
end, owner) \
|
|
_mmu_notifier_range_init(range, start, end)
|
|
|
|
static inline bool
|
|
mmu_notifier_range_blockable(const struct mmu_notifier_range *range)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static inline int mm_has_notifiers(struct mm_struct *mm)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void mmu_notifier_release(struct mm_struct *mm)
|
|
{
|
|
}
|
|
|
|
static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm,
|
|
unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int mmu_notifier_test_young(struct mm_struct *mm,
|
|
unsigned long address)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void mmu_notifier_change_pte(struct mm_struct *mm,
|
|
unsigned long address, pte_t pte)
|
|
{
|
|
}
|
|
|
|
static inline void
|
|
mmu_notifier_invalidate_range_start(struct mmu_notifier_range *range)
|
|
{
|
|
}
|
|
|
|
static inline int
|
|
mmu_notifier_invalidate_range_start_nonblock(struct mmu_notifier_range *range)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline
|
|
void mmu_notifier_invalidate_range_end(struct mmu_notifier_range *range)
|
|
{
|
|
}
|
|
|
|
static inline void mmu_notifier_arch_invalidate_secondary_tlbs(struct mm_struct *mm,
|
|
unsigned long start, unsigned long end)
|
|
{
|
|
}
|
|
|
|
static inline void mmu_notifier_subscriptions_init(struct mm_struct *mm)
|
|
{
|
|
}
|
|
|
|
static inline void mmu_notifier_subscriptions_destroy(struct mm_struct *mm)
|
|
{
|
|
}
|
|
|
|
#define mmu_notifier_range_update_to_read_only(r) false
|
|
|
|
#define ptep_clear_flush_young_notify ptep_clear_flush_young
|
|
#define pmdp_clear_flush_young_notify pmdp_clear_flush_young
|
|
#define ptep_clear_young_notify ptep_test_and_clear_young
|
|
#define pmdp_clear_young_notify pmdp_test_and_clear_young
|
|
#define ptep_clear_flush_notify ptep_clear_flush
|
|
#define pmdp_huge_clear_flush_notify pmdp_huge_clear_flush
|
|
#define pudp_huge_clear_flush_notify pudp_huge_clear_flush
|
|
#define set_pte_at_notify set_pte_at
|
|
|
|
static inline void mmu_notifier_synchronize(void)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_MMU_NOTIFIER */
|
|
|
|
#endif /* _LINUX_MMU_NOTIFIER_H */
|