diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 8760d55002..7e6a6076b1 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -31,6 +31,7 @@ #include "sysemu/kvm_int.h" #include "sysemu/runstate.h" #include "sysemu/cpus.h" +#include "sysemu/accel-blocker.h" #include "qemu/bswap.h" #include "exec/memory.h" #include "exec/ram_addr.h" @@ -46,6 +47,7 @@ #include "sysemu/hw_accel.h" #include "kvm-cpus.h" #include "sysemu/dirtylimit.h" +#include "qemu/range.h" #include "hw/boards.h" #include "monitor/stats.h" @@ -1292,6 +1294,7 @@ void kvm_set_max_memslot_size(hwaddr max_slot_size) kvm_max_slot_size = max_slot_size; } +/* Called with KVMMemoryListener.slots_lock held */ static void kvm_set_phys_mem(KVMMemoryListener *kml, MemoryRegionSection *section, bool add) { @@ -1326,14 +1329,12 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml, ram = memory_region_get_ram_ptr(mr) + mr_offset; ram_start_offset = memory_region_get_ram_addr(mr) + mr_offset; - kvm_slots_lock(); - if (!add) { do { slot_size = MIN(kvm_max_slot_size, size); mem = kvm_lookup_matching_slot(kml, start_addr, slot_size); if (!mem) { - goto out; + return; } if (mem->flags & KVM_MEM_LOG_DIRTY_PAGES) { /* @@ -1371,7 +1372,7 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml, start_addr += slot_size; size -= slot_size; } while (size); - goto out; + return; } /* register the new slot */ @@ -1396,9 +1397,6 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml, ram += slot_size; size -= slot_size; } while (size); - -out: - kvm_slots_unlock(); } static void *kvm_dirty_ring_reaper_thread(void *data) @@ -1455,18 +1453,95 @@ static void kvm_region_add(MemoryListener *listener, MemoryRegionSection *section) { KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener); + KVMMemoryUpdate *update; - memory_region_ref(section->mr); - kvm_set_phys_mem(kml, section, true); + update = g_new0(KVMMemoryUpdate, 1); + update->section = *section; + + QSIMPLEQ_INSERT_TAIL(&kml->transaction_add, update, next); } static void kvm_region_del(MemoryListener *listener, MemoryRegionSection *section) { KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener); + KVMMemoryUpdate *update; - kvm_set_phys_mem(kml, section, false); - memory_region_unref(section->mr); + update = g_new0(KVMMemoryUpdate, 1); + update->section = *section; + + QSIMPLEQ_INSERT_TAIL(&kml->transaction_del, update, next); +} + +static void kvm_region_commit(MemoryListener *listener) +{ + KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, + listener); + KVMMemoryUpdate *u1, *u2; + bool need_inhibit = false; + + if (QSIMPLEQ_EMPTY(&kml->transaction_add) && + QSIMPLEQ_EMPTY(&kml->transaction_del)) { + return; + } + + /* + * We have to be careful when regions to add overlap with ranges to remove. + * We have to simulate atomic KVM memslot updates by making sure no ioctl() + * is currently active. + * + * The lists are order by addresses, so it's easy to find overlaps. + */ + u1 = QSIMPLEQ_FIRST(&kml->transaction_del); + u2 = QSIMPLEQ_FIRST(&kml->transaction_add); + while (u1 && u2) { + Range r1, r2; + + range_init_nofail(&r1, u1->section.offset_within_address_space, + int128_get64(u1->section.size)); + range_init_nofail(&r2, u2->section.offset_within_address_space, + int128_get64(u2->section.size)); + + if (range_overlaps_range(&r1, &r2)) { + need_inhibit = true; + break; + } + if (range_lob(&r1) < range_lob(&r2)) { + u1 = QSIMPLEQ_NEXT(u1, next); + } else { + u2 = QSIMPLEQ_NEXT(u2, next); + } + } + + kvm_slots_lock(); + if (need_inhibit) { + accel_ioctl_inhibit_begin(); + } + + /* Remove all memslots before adding the new ones. */ + while (!QSIMPLEQ_EMPTY(&kml->transaction_del)) { + u1 = QSIMPLEQ_FIRST(&kml->transaction_del); + QSIMPLEQ_REMOVE_HEAD(&kml->transaction_del, next); + + kvm_set_phys_mem(kml, &u1->section, false); + memory_region_unref(u1->section.mr); + + g_free(u1); + } + while (!QSIMPLEQ_EMPTY(&kml->transaction_add)) { + u1 = QSIMPLEQ_FIRST(&kml->transaction_add); + QSIMPLEQ_REMOVE_HEAD(&kml->transaction_add, next); + + memory_region_ref(u1->section.mr); + kvm_set_phys_mem(kml, &u1->section, true); + + g_free(u1); + } + + if (need_inhibit) { + accel_ioctl_inhibit_end(); + } + kvm_slots_unlock(); } static void kvm_log_sync(MemoryListener *listener, @@ -1610,8 +1685,12 @@ void kvm_memory_listener_register(KVMState *s, KVMMemoryListener *kml, kml->slots[i].slot = i; } + QSIMPLEQ_INIT(&kml->transaction_add); + QSIMPLEQ_INIT(&kml->transaction_del); + kml->listener.region_add = kvm_region_add; kml->listener.region_del = kvm_region_del; + kml->listener.commit = kvm_region_commit; kml->listener.log_start = kvm_log_start; kml->listener.log_stop = kvm_log_stop; kml->listener.priority = 10; diff --git a/include/sysemu/kvm_int.h b/include/sysemu/kvm_int.h index 3b4adcdc10..60b520a13e 100644 --- a/include/sysemu/kvm_int.h +++ b/include/sysemu/kvm_int.h @@ -12,6 +12,7 @@ #include "exec/memory.h" #include "qapi/qapi-types-common.h" #include "qemu/accel.h" +#include "qemu/queue.h" #include "sysemu/kvm.h" typedef struct KVMSlot @@ -31,10 +32,17 @@ typedef struct KVMSlot ram_addr_t ram_start_offset; } KVMSlot; +typedef struct KVMMemoryUpdate { + QSIMPLEQ_ENTRY(KVMMemoryUpdate) next; + MemoryRegionSection section; +} KVMMemoryUpdate; + typedef struct KVMMemoryListener { MemoryListener listener; KVMSlot *slots; int as_id; + QSIMPLEQ_HEAD(, KVMMemoryUpdate) transaction_add; + QSIMPLEQ_HEAD(, KVMMemoryUpdate) transaction_del; } KVMMemoryListener; #define KVM_MSI_HASHTAB_SIZE 256