diff options
| author | Alistair Popple <apopple@nvidia.com> | 2023-07-25 15:42:07 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-18 19:12:41 +0200 |
| commit | 1af5a8109904b7f00828e7f9f63f5695b42f8215 (patch) | |
| tree | 2f37b095fb84abe7f1429c6714182f8d6b7bee1c /mm/mmu_notifier.c | |
| parent | mmu_notifiers: don't invalidate secondary TLBs as part of mmu_notifier_invali... (diff) | |
| download | linux-1af5a8109904b7f00828e7f9f63f5695b42f8215.tar.xz linux-1af5a8109904b7f00828e7f9f63f5695b42f8215.zip | |
mmu_notifiers: rename invalidate_range notifier
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>
Diffstat (limited to 'mm/mmu_notifier.c')
| -rw-r--r-- | mm/mmu_notifier.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index 453a156d93c0..ec3b068cbbe6 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -585,8 +585,8 @@ void __mmu_notifier_invalidate_range_end(struct mmu_notifier_range *range) lock_map_release(&__mmu_notifier_invalidate_range_start_map); } -void __mmu_notifier_invalidate_range(struct mm_struct *mm, - unsigned long start, unsigned long end) +void __mmu_notifier_arch_invalidate_secondary_tlbs(struct mm_struct *mm, + unsigned long start, unsigned long end) { struct mmu_notifier *subscription; int id; @@ -595,9 +595,10 @@ void __mmu_notifier_invalidate_range(struct mm_struct *mm, hlist_for_each_entry_rcu(subscription, &mm->notifier_subscriptions->list, hlist, srcu_read_lock_held(&srcu)) { - if (subscription->ops->invalidate_range) - subscription->ops->invalidate_range(subscription, mm, - start, end); + if (subscription->ops->arch_invalidate_secondary_tlbs) + subscription->ops->arch_invalidate_secondary_tlbs( + subscription, mm, + start, end); } srcu_read_unlock(&srcu, id); } @@ -616,6 +617,16 @@ int __mmu_notifier_register(struct mmu_notifier *subscription, mmap_assert_write_locked(mm); BUG_ON(atomic_read(&mm->mm_users) <= 0); + /* + * Subsystems should only register for invalidate_secondary_tlbs() or + * invalidate_range_start()/end() callbacks, not both. + */ + if (WARN_ON_ONCE(subscription && + (subscription->ops->arch_invalidate_secondary_tlbs && + (subscription->ops->invalidate_range_start || + subscription->ops->invalidate_range_end)))) + return -EINVAL; + if (!mm->notifier_subscriptions) { /* * kmalloc cannot be called under mm_take_all_locks(), but we |