diff options
Diffstat (limited to 'virt/kvm/kvm_main.c')
| -rw-r--r-- | virt/kvm/kvm_main.c | 52 |
1 files changed, 27 insertions, 25 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 44b92d773156..5142c054b03c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -702,30 +702,31 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, /* * .change_pte() must be surrounded by .invalidate_range_{start,end}(). - * If mmu_notifier_count is zero, then no in-progress invalidations, - * including this one, found a relevant memslot at start(); rechecking - * memslots here is unnecessary. Note, a false positive (count elevated - * by a different invalidation) is sub-optimal but functionally ok. + * If mmu_invalidate_in_progress is zero, then no in-progress + * invalidations, including this one, found a relevant memslot at + * start(); rechecking memslots here is unnecessary. Note, a false + * positive (count elevated by a different invalidation) is sub-optimal + * but functionally ok. */ WARN_ON_ONCE(!READ_ONCE(kvm->mn_active_invalidate_count)); - if (!READ_ONCE(kvm->mmu_notifier_count)) + if (!READ_ONCE(kvm->mmu_invalidate_in_progress)) return; kvm_handle_hva_range(mn, address, address + 1, pte, kvm_set_spte_gfn); } -void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start, - unsigned long end) +void kvm_mmu_invalidate_begin(struct kvm *kvm, unsigned long start, + unsigned long end) { /* * The count increase must become visible at unlock time as no * spte can be established without taking the mmu_lock and * count is also read inside the mmu_lock critical section. */ - kvm->mmu_notifier_count++; - if (likely(kvm->mmu_notifier_count == 1)) { - kvm->mmu_notifier_range_start = start; - kvm->mmu_notifier_range_end = end; + kvm->mmu_invalidate_in_progress++; + if (likely(kvm->mmu_invalidate_in_progress == 1)) { + kvm->mmu_invalidate_range_start = start; + kvm->mmu_invalidate_range_end = end; } else { /* * Fully tracking multiple concurrent ranges has diminishing @@ -736,10 +737,10 @@ void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start, * accumulate and persist until all outstanding invalidates * complete. */ - kvm->mmu_notifier_range_start = - min(kvm->mmu_notifier_range_start, start); - kvm->mmu_notifier_range_end = - max(kvm->mmu_notifier_range_end, end); + kvm->mmu_invalidate_range_start = + min(kvm->mmu_invalidate_range_start, start); + kvm->mmu_invalidate_range_end = + max(kvm->mmu_invalidate_range_end, end); } } @@ -752,7 +753,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, .end = range->end, .pte = __pte(0), .handler = kvm_unmap_gfn_range, - .on_lock = kvm_inc_notifier_count, + .on_lock = kvm_mmu_invalidate_begin, .on_unlock = kvm_arch_guest_memory_reclaimed, .flush_on_ret = true, .may_block = mmu_notifier_range_blockable(range), @@ -763,7 +764,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, /* * Prevent memslot modification between range_start() and range_end() * so that conditionally locking provides the same result in both - * functions. Without that guarantee, the mmu_notifier_count + * functions. Without that guarantee, the mmu_invalidate_in_progress * adjustments will be imbalanced. * * Pairs with the decrement in range_end(). @@ -779,7 +780,8 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, * any given time, and the caches themselves can check for hva overlap, * i.e. don't need to rely on memslot overlap checks for performance. * Because this runs without holding mmu_lock, the pfn caches must use - * mn_active_invalidate_count (see above) instead of mmu_notifier_count. + * mn_active_invalidate_count (see above) instead of + * mmu_invalidate_in_progress. */ gfn_to_pfn_cache_invalidate_start(kvm, range->start, range->end, hva_range.may_block); @@ -789,22 +791,22 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, return 0; } -void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start, - unsigned long end) +void kvm_mmu_invalidate_end(struct kvm *kvm, unsigned long start, + unsigned long end) { /* * This sequence increase will notify the kvm page fault that * the page that is going to be mapped in the spte could have * been freed. */ - kvm->mmu_notifier_seq++; + kvm->mmu_invalidate_seq++; smp_wmb(); /* * The above sequence increase must be visible before the * below count decrease, which is ensured by the smp_wmb above - * in conjunction with the smp_rmb in mmu_notifier_retry(). + * in conjunction with the smp_rmb in mmu_invalidate_retry(). */ - kvm->mmu_notifier_count--; + kvm->mmu_invalidate_in_progress--; } static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, @@ -816,7 +818,7 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, .end = range->end, .pte = __pte(0), .handler = (void *)kvm_null_fn, - .on_lock = kvm_dec_notifier_count, + .on_lock = kvm_mmu_invalidate_end, .on_unlock = (void *)kvm_null_fn, .flush_on_ret = false, .may_block = mmu_notifier_range_blockable(range), @@ -837,7 +839,7 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, if (wake) rcuwait_wake_up(&kvm->mn_memslots_update_rcuwait); - BUG_ON(kvm->mmu_notifier_count < 0); + BUG_ON(kvm->mmu_invalidate_in_progress < 0); } static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn, |