diff options
| author | Ben Gardon <bgardon@google.com> | 2021-03-15 16:38:02 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-03-16 14:16:17 -0400 |
| commit | b601c3bc9d5053065acdaa1481c21481d0dc3f10 (patch) | |
| tree | 7640e9ffb25982d1b6cf8a7fd19b8fe5f6459448 /arch/x86/kvm/mmu/tdp_iter.c | |
| parent | 14f6fec2e8e04b83c87c339b8d8ff4cc62b23d35 (diff) | |
KVM: x86/mmu: Factor out tdp_iter_return_to_root
In tdp_mmu_iter_cond_resched there is a call to tdp_iter_start which
causes the iterator to continue its walk over the paging structure from
the root. This is needed after a yield as paging structure could have
been freed in the interim.
The tdp_iter_start call is not very clear and something of a hack. It
requires exposing tdp_iter fields not used elsewhere in tdp_mmu.c and
the effect is not obvious from the function name. Factor a more aptly
named function out of tdp_iter_start and call it from
tdp_mmu_iter_cond_resched and tdp_iter_start.
No functional change intended.
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20210315233803.2706477-4-bgardon@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/mmu/tdp_iter.c')
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_iter.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/arch/x86/kvm/mmu/tdp_iter.c b/arch/x86/kvm/mmu/tdp_iter.c index e5f148106e20..f7f94ea65243 100644 --- a/arch/x86/kvm/mmu/tdp_iter.c +++ b/arch/x86/kvm/mmu/tdp_iter.c @@ -21,6 +21,21 @@ static gfn_t round_gfn_for_level(gfn_t gfn, int level) } /* + * Return the TDP iterator to the root PT and allow it to continue its + * traversal over the paging structure from there. + */ +void tdp_iter_restart(struct tdp_iter *iter) +{ + iter->yielded_gfn = iter->next_last_level_gfn; + iter->level = iter->root_level; + + iter->gfn = round_gfn_for_level(iter->next_last_level_gfn, iter->level); + tdp_iter_refresh_sptep(iter); + + iter->valid = true; +} + +/* * Sets a TDP iterator to walk a pre-order traversal of the paging structure * rooted at root_pt, starting with the walk to translate next_last_level_gfn. */ @@ -31,16 +46,11 @@ void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level, WARN_ON(root_level > PT64_ROOT_MAX_LEVEL); iter->next_last_level_gfn = next_last_level_gfn; - iter->yielded_gfn = iter->next_last_level_gfn; iter->root_level = root_level; iter->min_level = min_level; - iter->level = root_level; - iter->pt_path[iter->level - 1] = (tdp_ptep_t)root_pt; + iter->pt_path[iter->root_level - 1] = (tdp_ptep_t)root_pt; - iter->gfn = round_gfn_for_level(iter->next_last_level_gfn, iter->level); - tdp_iter_refresh_sptep(iter); - - iter->valid = true; + tdp_iter_restart(iter); } /* |