From 84516e5b8db66b8a169a8fdd4c25568ed0b67a3a Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 24 Sep 2019 10:47:49 -0400 Subject: kvm: clear dirty bitmaps from all overlapping memslots Currently MemoryRegionSection has 1:1 mapping to KVMSlot. However next patch will allow splitting MemoryRegionSection into several KVMSlot-s, make sure that kvm_physical_log_slot_clear() is able to handle such 1:N mapping. Signed-off-by: Paolo Bonzini Signed-off-by: Igor Mammedov Reviewed-by: Peter Xu Message-Id: <20190924144751.24149-3-imammedo@redhat.com> Acked-by: Paolo Bonzini Signed-off-by: Christian Borntraeger --- accel/kvm/kvm-all.c | 36 ++++++++++++++++++++++-------------- 1 file changed, 22 insertions(+), 14 deletions(-) (limited to 'accel') diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index a85ec09486..ff9b95c0d1 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -589,8 +589,8 @@ static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start, * satisfy the KVM interface requirement. Firstly, do the start * page alignment on 64 host pages */ - bmap_start = (start - mem->start_addr) & KVM_CLEAR_LOG_MASK; - start_delta = start - mem->start_addr - bmap_start; + bmap_start = start & KVM_CLEAR_LOG_MASK; + start_delta = start - bmap_start; bmap_start /= psize; /* @@ -694,8 +694,8 @@ static int kvm_physical_log_clear(KVMMemoryListener *kml, MemoryRegionSection *section) { KVMState *s = kvm_state; - uint64_t start, size; - KVMSlot *mem = NULL; + uint64_t start, size, offset, count; + KVMSlot *mem; int ret, i; if (!s->manual_dirty_log_protect) { @@ -713,22 +713,30 @@ static int kvm_physical_log_clear(KVMMemoryListener *kml, kvm_slots_lock(kml); - /* Find any possible slot that covers the section */ for (i = 0; i < s->nr_slots; i++) { mem = &kml->slots[i]; - if (mem->start_addr <= start && - start + size <= mem->start_addr + mem->memory_size) { + /* Discard slots that are empty or do not overlap the section */ + if (!mem->memory_size || + mem->start_addr > start + size - 1 || + start > mem->start_addr + mem->memory_size - 1) { + continue; + } + + if (start >= mem->start_addr) { + /* The slot starts before section or is aligned to it. */ + offset = start - mem->start_addr; + count = MIN(mem->memory_size - offset, size); + } else { + /* The slot starts after section. */ + offset = 0; + count = MIN(mem->memory_size, size - (mem->start_addr - start)); + } + ret = kvm_log_clear_one_slot(mem, kml->as_id, offset, count); + if (ret < 0) { break; } } - /* - * We should always find one memslot until this point, otherwise - * there could be something wrong from the upper layer - */ - assert(mem && i != s->nr_slots); - ret = kvm_log_clear_one_slot(mem, kml->as_id, start, size); - kvm_slots_unlock(kml); return ret; -- cgit v1.2.3