diff options
| author | Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> | 2018-04-30 18:33:25 +0200 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2018-07-13 09:48:57 +0200 |
| commit | afdad61615cc37fef91bc70af7ee5b293785fbd6 (patch) | |
| tree | 7ff6e123b9b925f7d7a53b66d201dcd5a383e58c /arch/s390/kvm/priv.c | |
| parent | 03133347b4452ef9b1f1456b92f5fafa467c0655 (diff) | |
| download | linux-afdad61615cc37fef91bc70af7ee5b293785fbd6.tar.bz2 | |
KVM: s390: Fix storage attributes migration with memory slots
This is a fix for several issues that were found in the original code
for storage attributes migration.
Now no bitmap is allocated to keep track of dirty storage attributes;
the extra bits of the per-memslot bitmap that are always present anyway
are now used for this purpose.
The code has also been refactored a little to improve readability.
Fixes: 190df4a212a ("KVM: s390: CMMA tracking, ESSA emulation, migration mode")
Fixes: 4036e3874a1 ("KVM: s390: ioctls to get and set guest storage attributes")
Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Message-Id: <1525106005-13931-3-git-send-email-imbrenda@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390/kvm/priv.c')
| -rw-r--r-- | arch/s390/kvm/priv.c | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index c4da375553e8..c623b6f1dd4e 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -987,9 +987,11 @@ static int handle_pfmf(struct kvm_vcpu *vcpu) return 0; } -static inline int do_essa(struct kvm_vcpu *vcpu, const int orc) +/* + * Must be called with relevant read locks held (kvm->mm->mmap_sem, kvm->srcu) + */ +static inline int __do_essa(struct kvm_vcpu *vcpu, const int orc) { - struct kvm_s390_migration_state *ms = vcpu->kvm->arch.migration_state; int r1, r2, nappended, entries; unsigned long gfn, hva, res, pgstev, ptev; unsigned long *cbrlo; @@ -1039,10 +1041,12 @@ static inline int do_essa(struct kvm_vcpu *vcpu, const int orc) cbrlo[entries] = gfn << PAGE_SHIFT; } - if (orc && gfn < ms->bitmap_size) { - /* increment only if we are really flipping the bit to 1 */ - if (!test_and_set_bit(gfn, ms->pgste_bitmap)) - atomic64_inc(&ms->dirty_pages); + if (orc) { + struct kvm_memory_slot *ms = gfn_to_memslot(vcpu->kvm, gfn); + + /* Increment only if we are really flipping the bit */ + if (ms && !test_and_set_bit(gfn - ms->base_gfn, kvm_second_dirty_bitmap(ms))) + atomic64_inc(&vcpu->kvm->arch.cmma_dirty_pages); } return nappended; @@ -1071,7 +1075,7 @@ static int handle_essa(struct kvm_vcpu *vcpu) : ESSA_SET_STABLE_IF_RESIDENT)) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); - if (likely(!vcpu->kvm->arch.migration_state)) { + if (!vcpu->kvm->arch.migration_mode) { /* * CMMA is enabled in the KVM settings, but is disabled in * the SIE block and in the mm_context, and we are not doing @@ -1099,10 +1103,16 @@ static int handle_essa(struct kvm_vcpu *vcpu) /* Retry the ESSA instruction */ kvm_s390_retry_instr(vcpu); } else { - /* Account for the possible extra cbrl entry */ - i = do_essa(vcpu, orc); + int srcu_idx; + + down_read(&vcpu->kvm->mm->mmap_sem); + srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + i = __do_essa(vcpu, orc); + srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx); + up_read(&vcpu->kvm->mm->mmap_sem); if (i < 0) return i; + /* Account for the possible extra cbrl entry */ entries += i; } vcpu->arch.sie_block->cbrlo &= PAGE_MASK; /* reset nceo */ |