|  | /* | 
|  | * QEMU Hyper-V Dynamic Memory Protocol driver | 
|  | * | 
|  | * Copyright (C) 2020-2023 Oracle and/or its affiliates. | 
|  | * | 
|  | * This work is licensed under the terms of the GNU GPL, version 2 or later. | 
|  | * See the COPYING file in the top-level directory. | 
|  | */ | 
|  |  | 
|  | #include "hv-balloon-internal.h" | 
|  |  | 
|  | #include "exec/address-spaces.h" | 
|  | #include "exec/cpu-common.h" | 
|  | #include "exec/ramblock.h" | 
|  | #include "hw/boards.h" | 
|  | #include "hw/hyperv/dynmem-proto.h" | 
|  | #include "hw/hyperv/hv-balloon.h" | 
|  | #include "hw/hyperv/vmbus.h" | 
|  | #include "hw/mem/memory-device.h" | 
|  | #include "hw/mem/pc-dimm.h" | 
|  | #include "hw/qdev-core.h" | 
|  | #include "hw/qdev-properties.h" | 
|  | #include "monitor/qdev.h" | 
|  | #include "qapi/error.h" | 
|  | #include "qapi/qapi-commands-machine.h" | 
|  | #include "qapi/qapi-events-machine.h" | 
|  | #include "qapi/qapi-types-machine.h" | 
|  | #include "qapi/qmp/qdict.h" | 
|  | #include "qapi/visitor.h" | 
|  | #include "qemu/error-report.h" | 
|  | #include "qemu/module.h" | 
|  | #include "qemu/units.h" | 
|  | #include "qemu/timer.h" | 
|  | #include "sysemu/balloon.h" | 
|  | #include "sysemu/hostmem.h" | 
|  | #include "sysemu/reset.h" | 
|  | #include "hv-balloon-our_range_memslots.h" | 
|  | #include "hv-balloon-page_range_tree.h" | 
|  | #include "trace.h" | 
|  |  | 
|  | #define HV_BALLOON_ADDR_PROP "addr" | 
|  | #define HV_BALLOON_MEMDEV_PROP "memdev" | 
|  | #define HV_BALLOON_GUID "525074DC-8985-46e2-8057-A307DC18A502" | 
|  |  | 
|  | /* | 
|  | * Some Windows versions (at least Server 2019) will crash with various | 
|  | * error codes when receiving DM protocol requests (at least | 
|  | * DM_MEM_HOT_ADD_REQUEST) immediately after boot. | 
|  | * | 
|  | * It looks like Hyper-V from Server 2016 uses a 50-second after-boot | 
|  | * delay, probably to workaround this issue, so we'll use this value, too. | 
|  | */ | 
|  | #define HV_BALLOON_POST_INIT_WAIT (50 * 1000) | 
|  |  | 
|  | #define HV_BALLOON_HA_CHUNK_SIZE (2 * GiB) | 
|  | #define HV_BALLOON_HA_CHUNK_PAGES (HV_BALLOON_HA_CHUNK_SIZE / HV_BALLOON_PAGE_SIZE) | 
|  |  | 
|  | #define HV_BALLOON_HA_MEMSLOT_SIZE_ALIGN (128 * MiB) | 
|  |  | 
|  | #define HV_BALLOON_HR_CHUNK_PAGES 585728 | 
|  | /* | 
|  | *                                ^ that's the maximum number of pages | 
|  | * that Windows returns in one hot remove response | 
|  | * | 
|  | * If the number requested is too high Windows will no longer honor | 
|  | * these requests | 
|  | */ | 
|  |  | 
|  | struct HvBalloonClass { | 
|  | VMBusDeviceClass parent_class; | 
|  | } HvBalloonClass; | 
|  |  | 
|  | typedef enum State { | 
|  | /* not a real state */ | 
|  | S_NO_CHANGE = 0, | 
|  |  | 
|  | S_WAIT_RESET, | 
|  | S_POST_RESET_CLOSED, | 
|  |  | 
|  | /* init flow */ | 
|  | S_VERSION, | 
|  | S_CAPS, | 
|  | S_POST_INIT_WAIT, | 
|  |  | 
|  | S_IDLE, | 
|  |  | 
|  | /* balloon op flow */ | 
|  | S_BALLOON_POSTING, | 
|  | S_BALLOON_RB_WAIT, | 
|  | S_BALLOON_REPLY_WAIT, | 
|  |  | 
|  | /* unballoon + hot add ops flow */ | 
|  | S_UNBALLOON_POSTING, | 
|  | S_UNBALLOON_RB_WAIT, | 
|  | S_UNBALLOON_REPLY_WAIT, | 
|  | S_HOT_ADD_SETUP, | 
|  | S_HOT_ADD_RB_WAIT, | 
|  | S_HOT_ADD_POSTING, | 
|  | S_HOT_ADD_REPLY_WAIT, | 
|  | } State; | 
|  |  | 
|  | typedef struct StateDesc { | 
|  | State state; | 
|  | const char *desc; | 
|  | } StateDesc; | 
|  |  | 
|  | typedef struct HvBalloon { | 
|  | VMBusDevice parent; | 
|  | State state; | 
|  |  | 
|  | union dm_version version; | 
|  | union dm_caps caps; | 
|  |  | 
|  | QEMUTimer post_init_timer; | 
|  |  | 
|  | unsigned int trans_id; | 
|  |  | 
|  | struct { | 
|  | bool enabled; | 
|  | bool received; | 
|  | uint64_t committed; | 
|  | uint64_t available; | 
|  | } status_report; | 
|  |  | 
|  | /* Guest target size */ | 
|  | uint64_t target; | 
|  | bool target_changed; | 
|  |  | 
|  | /* Current (un)balloon / hot-add operation parameters */ | 
|  | union { | 
|  | uint64_t balloon_diff; | 
|  |  | 
|  | struct { | 
|  | uint64_t unballoon_diff; | 
|  | uint64_t hot_add_diff; | 
|  | }; | 
|  |  | 
|  | struct { | 
|  | PageRange hot_add_range; | 
|  | uint64_t ha_current_count; | 
|  | }; | 
|  | }; | 
|  |  | 
|  | OurRangeMemslots *our_range; | 
|  |  | 
|  | /* Count of memslots covering our memory */ | 
|  | unsigned int memslot_count; | 
|  |  | 
|  | /* Nominal size of each memslot (the last one might be smaller) */ | 
|  | uint64_t memslot_size; | 
|  |  | 
|  | /* Non-ours removed memory */ | 
|  | PageRangeTree removed_guest, removed_both; | 
|  |  | 
|  | /* Grand totals of removed memory (both ours and non-ours) */ | 
|  | uint64_t removed_guest_ctr, removed_both_ctr; | 
|  |  | 
|  | /* MEMORY_DEVICE props */ | 
|  | uint64_t addr; | 
|  | HostMemoryBackend *hostmem; | 
|  | MemoryRegion *mr; | 
|  | } HvBalloon; | 
|  |  | 
|  | OBJECT_DEFINE_TYPE_WITH_INTERFACES(HvBalloon, hv_balloon, HV_BALLOON, VMBUS_DEVICE, \ | 
|  | { TYPE_MEMORY_DEVICE }, { }) | 
|  |  | 
|  | #define HV_BALLOON_SET_STATE(hvb, news)             \ | 
|  | do {                                            \ | 
|  | assert(news != S_NO_CHANGE);                \ | 
|  | hv_balloon_state_set(hvb, news, # news);    \ | 
|  | } while (0) | 
|  |  | 
|  | #define HV_BALLOON_STATE_DESC_SET(stdesc, news)         \ | 
|  | _hv_balloon_state_desc_set(stdesc, news, # news) | 
|  |  | 
|  | #define HV_BALLOON_STATE_DESC_INIT \ | 
|  | {                              \ | 
|  | .state = S_NO_CHANGE,      \ | 
|  | } | 
|  |  | 
|  | typedef struct HvBalloonReq { | 
|  | VMBusChanReq vmreq; | 
|  | } HvBalloonReq; | 
|  |  | 
|  | /* total our memory includes parts currently removed from the guest */ | 
|  | static uint64_t hv_balloon_total_our_ram(HvBalloon *balloon) | 
|  | { | 
|  | if (!balloon->our_range) { | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | return balloon->our_range->range.added; | 
|  | } | 
|  |  | 
|  | /* TODO: unify the code below with virtio-balloon and cache the value */ | 
|  | static int build_dimm_list(Object *obj, void *opaque) | 
|  | { | 
|  | GSList **list = opaque; | 
|  |  | 
|  | if (object_dynamic_cast(obj, TYPE_PC_DIMM)) { | 
|  | DeviceState *dev = DEVICE(obj); | 
|  | if (dev->realized) { /* only realized DIMMs matter */ | 
|  | *list = g_slist_prepend(*list, dev); | 
|  | } | 
|  | } | 
|  |  | 
|  | object_child_foreach(obj, build_dimm_list, opaque); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static ram_addr_t get_current_ram_size(void) | 
|  | { | 
|  | GSList *list = NULL, *item; | 
|  | ram_addr_t size = current_machine->ram_size; | 
|  |  | 
|  | build_dimm_list(qdev_get_machine(), &list); | 
|  | for (item = list; item; item = g_slist_next(item)) { | 
|  | Object *obj = OBJECT(item->data); | 
|  | if (!strcmp(object_get_typename(obj), TYPE_PC_DIMM)) | 
|  | size += object_property_get_int(obj, PC_DIMM_SIZE_PROP, | 
|  | &error_abort); | 
|  | } | 
|  | g_slist_free(list); | 
|  |  | 
|  | return size; | 
|  | } | 
|  |  | 
|  | /* total RAM includes memory currently removed from the guest */ | 
|  | static uint64_t hv_balloon_total_ram(HvBalloon *balloon) | 
|  | { | 
|  | ram_addr_t ram_size = get_current_ram_size(); | 
|  | uint64_t ram_size_pages = ram_size >> HV_BALLOON_PFN_SHIFT; | 
|  | uint64_t our_ram_size_pages = hv_balloon_total_our_ram(balloon); | 
|  |  | 
|  | assert(ram_size_pages > 0); | 
|  |  | 
|  | return SUM_SATURATE_U64(ram_size_pages, our_ram_size_pages); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * calculating the total RAM size is a slow operation, | 
|  | * avoid it as much as possible | 
|  | */ | 
|  | static uint64_t hv_balloon_total_removed_rs(HvBalloon *balloon, | 
|  | uint64_t ram_size_pages) | 
|  | { | 
|  | uint64_t total_removed; | 
|  |  | 
|  | total_removed = SUM_SATURATE_U64(balloon->removed_guest_ctr, | 
|  | balloon->removed_both_ctr); | 
|  |  | 
|  | /* possible if guest returns pages outside actual RAM */ | 
|  | if (total_removed > ram_size_pages) { | 
|  | total_removed = ram_size_pages; | 
|  | } | 
|  |  | 
|  | return total_removed; | 
|  | } | 
|  |  | 
|  | /* Returns whether the state has actually changed */ | 
|  | static bool hv_balloon_state_set(HvBalloon *balloon, | 
|  | State newst, const char *newststr) | 
|  | { | 
|  | if (newst == S_NO_CHANGE || balloon->state == newst) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | balloon->state = newst; | 
|  | trace_hv_balloon_state_change(newststr); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | static void _hv_balloon_state_desc_set(StateDesc *stdesc, | 
|  | State newst, const char *newststr) | 
|  | { | 
|  | /* state setting is only permitted on a freshly init desc */ | 
|  | assert(stdesc->state == S_NO_CHANGE); | 
|  |  | 
|  | assert(newst != S_NO_CHANGE); | 
|  |  | 
|  | stdesc->state = newst; | 
|  | stdesc->desc = newststr; | 
|  | } | 
|  |  | 
|  | static VMBusChannel *hv_balloon_get_channel_maybe(HvBalloon *balloon) | 
|  | { | 
|  | return vmbus_device_channel(&balloon->parent, 0); | 
|  | } | 
|  |  | 
|  | static VMBusChannel *hv_balloon_get_channel(HvBalloon *balloon) | 
|  | { | 
|  | VMBusChannel *chan; | 
|  |  | 
|  | chan = hv_balloon_get_channel_maybe(balloon); | 
|  | assert(chan != NULL); | 
|  | return chan; | 
|  | } | 
|  |  | 
|  | static ssize_t hv_balloon_send_packet(VMBusChannel *chan, | 
|  | struct dm_message *msg) | 
|  | { | 
|  | int ret; | 
|  |  | 
|  | ret = vmbus_channel_reserve(chan, 0, msg->hdr.size); | 
|  | if (ret < 0) { | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | return vmbus_channel_send(chan, VMBUS_PACKET_DATA_INBAND, | 
|  | NULL, 0, msg, msg->hdr.size, false, | 
|  | msg->hdr.trans_id); | 
|  | } | 
|  |  | 
|  | static bool hv_balloon_unballoon_get_source(HvBalloon *balloon, | 
|  | PageRangeTree *dtree, | 
|  | uint64_t **dctr, | 
|  | bool *is_our_range) | 
|  | { | 
|  | OurRange *our_range = OUR_RANGE(balloon->our_range); | 
|  |  | 
|  | /* Try the boot memory first */ | 
|  | if (g_tree_nnodes(balloon->removed_guest.t) > 0) { | 
|  | *dtree = balloon->removed_guest; | 
|  | *dctr = &balloon->removed_guest_ctr; | 
|  | *is_our_range = false; | 
|  | } else if (g_tree_nnodes(balloon->removed_both.t) > 0) { | 
|  | *dtree = balloon->removed_both; | 
|  | *dctr = &balloon->removed_both_ctr; | 
|  | *is_our_range = false; | 
|  | } else if (!our_range) { | 
|  | return false; | 
|  | } else if (!our_range_is_removed_tree_empty(our_range, false)) { | 
|  | *dtree = our_range_get_removed_tree(our_range, false); | 
|  | *dctr = &balloon->removed_guest_ctr; | 
|  | *is_our_range = true; | 
|  | } else if (!our_range_is_removed_tree_empty(our_range, true)) { | 
|  | *dtree = our_range_get_removed_tree(our_range, true); | 
|  | *dctr = &balloon->removed_both_ctr; | 
|  | *is_our_range = true; | 
|  | } else { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | return true; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_unballoon_rb_wait(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | VMBusChannel *chan = hv_balloon_get_channel(balloon); | 
|  | struct dm_unballoon_request *ur; | 
|  | size_t ur_size = sizeof(*ur) + sizeof(ur->range_array[0]); | 
|  |  | 
|  | assert(balloon->state == S_UNBALLOON_RB_WAIT); | 
|  |  | 
|  | if (vmbus_channel_reserve(chan, 0, ur_size) < 0) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_UNBALLOON_POSTING); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_unballoon_posting(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | VMBusChannel *chan = hv_balloon_get_channel(balloon); | 
|  | PageRangeTree dtree; | 
|  | uint64_t *dctr; | 
|  | bool our_range; | 
|  | struct dm_unballoon_request *ur; | 
|  | size_t ur_size = sizeof(*ur) + sizeof(ur->range_array[0]); | 
|  | PageRange range; | 
|  | bool bret; | 
|  | ssize_t ret; | 
|  |  | 
|  | assert(balloon->state == S_UNBALLOON_POSTING); | 
|  | assert(balloon->unballoon_diff > 0); | 
|  |  | 
|  | if (!hv_balloon_unballoon_get_source(balloon, &dtree, &dctr, &our_range)) { | 
|  | error_report("trying to unballoon but nothing seems to be ballooned"); | 
|  | /* | 
|  | * there is little we can do as we might have already | 
|  | * sent the guest a partial request we can't cancel | 
|  | */ | 
|  | return; | 
|  | } | 
|  |  | 
|  | assert(balloon->our_range || !our_range); | 
|  | assert(dtree.t); | 
|  | assert(dctr); | 
|  |  | 
|  | ur = alloca(ur_size); | 
|  | memset(ur, 0, ur_size); | 
|  | ur->hdr.type = DM_UNBALLOON_REQUEST; | 
|  | ur->hdr.size = ur_size; | 
|  | ur->hdr.trans_id = balloon->trans_id; | 
|  |  | 
|  | bret = hvb_page_range_tree_pop(dtree, &range, MIN(balloon->unballoon_diff, | 
|  | HV_BALLOON_HA_CHUNK_PAGES)); | 
|  | assert(bret); | 
|  | /* TODO: madvise? */ | 
|  |  | 
|  | *dctr -= range.count; | 
|  | balloon->unballoon_diff -= range.count; | 
|  |  | 
|  | ur->range_count = 1; | 
|  | ur->range_array[0].finfo.start_page = range.start; | 
|  | ur->range_array[0].finfo.page_cnt = range.count; | 
|  | ur->more_pages = balloon->unballoon_diff > 0; | 
|  |  | 
|  | trace_hv_balloon_outgoing_unballoon(ur->hdr.trans_id, | 
|  | range.count, range.start, | 
|  | balloon->unballoon_diff); | 
|  |  | 
|  | if (ur->more_pages) { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_UNBALLOON_RB_WAIT); | 
|  | } else { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_UNBALLOON_REPLY_WAIT); | 
|  | } | 
|  |  | 
|  | ret = vmbus_channel_send(chan, VMBUS_PACKET_DATA_INBAND, | 
|  | NULL, 0, ur, ur_size, false, | 
|  | ur->hdr.trans_id); | 
|  | if (ret <= 0) { | 
|  | error_report("error %zd when posting unballoon msg, expect problems", | 
|  | ret); | 
|  | } | 
|  | } | 
|  |  | 
|  | static bool hv_balloon_our_range_ensure(HvBalloon *balloon) | 
|  | { | 
|  | uint64_t align; | 
|  | MemoryRegion *hostmem_mr; | 
|  | g_autoptr(OurRangeMemslots) our_range_memslots = NULL; | 
|  | OurRange *our_range; | 
|  |  | 
|  | if (balloon->our_range) { | 
|  | return true; | 
|  | } | 
|  |  | 
|  | if (!balloon->hostmem) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | align = (1 << balloon->caps.cap_bits.hot_add_alignment) * MiB; | 
|  | assert(QEMU_IS_ALIGNED(balloon->addr, align)); | 
|  |  | 
|  | hostmem_mr = host_memory_backend_get_memory(balloon->hostmem); | 
|  |  | 
|  | our_range_memslots = hvb_our_range_memslots_new(balloon->addr, | 
|  | balloon->mr, hostmem_mr, | 
|  | OBJECT(balloon), | 
|  | balloon->memslot_count, | 
|  | balloon->memslot_size); | 
|  | our_range = OUR_RANGE(our_range_memslots); | 
|  |  | 
|  | if (hvb_page_range_tree_intree_any(balloon->removed_guest, | 
|  | our_range->range.start, | 
|  | our_range->range.count) || | 
|  | hvb_page_range_tree_intree_any(balloon->removed_both, | 
|  | our_range->range.start, | 
|  | our_range->range.count)) { | 
|  | error_report("some parts of the memory backend were already returned by the guest. this should not happen, please reboot the guest and try again"); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | trace_hv_balloon_our_range_add(our_range->range.count, | 
|  | our_range->range.start); | 
|  |  | 
|  | balloon->our_range = g_steal_pointer(&our_range_memslots); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_hot_add_setup(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | /* need to make copy since it is in union with hot_add_range */ | 
|  | uint64_t hot_add_diff = balloon->hot_add_diff; | 
|  | PageRange *hot_add_range = &balloon->hot_add_range; | 
|  | uint64_t align, our_range_remaining; | 
|  | OurRange *our_range; | 
|  |  | 
|  | assert(balloon->state == S_HOT_ADD_SETUP); | 
|  | assert(hot_add_diff > 0); | 
|  |  | 
|  | if (!hv_balloon_our_range_ensure(balloon)) { | 
|  | goto ret_idle; | 
|  | } | 
|  |  | 
|  | our_range = OUR_RANGE(balloon->our_range); | 
|  |  | 
|  | align = (1 << balloon->caps.cap_bits.hot_add_alignment) * | 
|  | (MiB / HV_BALLOON_PAGE_SIZE); | 
|  |  | 
|  | /* Absolute GPA in pages */ | 
|  | hot_add_range->start = our_range_get_remaining_start(our_range); | 
|  | assert(QEMU_IS_ALIGNED(hot_add_range->start, align)); | 
|  |  | 
|  | our_range_remaining = our_range_get_remaining_size(our_range); | 
|  | hot_add_range->count = MIN(our_range_remaining, hot_add_diff); | 
|  | hot_add_range->count = QEMU_ALIGN_DOWN(hot_add_range->count, align); | 
|  | if (hot_add_range->count == 0) { | 
|  | goto ret_idle; | 
|  | } | 
|  |  | 
|  | hvb_our_range_memslots_ensure_mapped_additional(balloon->our_range, | 
|  | hot_add_range->count); | 
|  |  | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_RB_WAIT); | 
|  | return; | 
|  |  | 
|  | ret_idle: | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_IDLE); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_hot_add_rb_wait(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | VMBusChannel *chan = hv_balloon_get_channel(balloon); | 
|  | struct dm_hot_add *ha; | 
|  | size_t ha_size = sizeof(*ha) + sizeof(ha->range); | 
|  |  | 
|  | assert(balloon->state == S_HOT_ADD_RB_WAIT); | 
|  |  | 
|  | if (vmbus_channel_reserve(chan, 0, ha_size) < 0) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_POSTING); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_hot_add_posting(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | PageRange *hot_add_range = &balloon->hot_add_range; | 
|  | uint64_t *current_count = &balloon->ha_current_count; | 
|  | VMBusChannel *chan = hv_balloon_get_channel(balloon); | 
|  | struct dm_hot_add *ha; | 
|  | size_t ha_size = sizeof(*ha) + sizeof(ha->range); | 
|  | union dm_mem_page_range *ha_region; | 
|  | uint64_t align, chunk_max_size; | 
|  | ssize_t ret; | 
|  |  | 
|  | assert(balloon->state == S_HOT_ADD_POSTING); | 
|  | assert(hot_add_range->count > 0); | 
|  |  | 
|  | align = (1 << balloon->caps.cap_bits.hot_add_alignment) * | 
|  | (MiB / HV_BALLOON_PAGE_SIZE); | 
|  | if (align >= HV_BALLOON_HA_CHUNK_PAGES) { | 
|  | /* | 
|  | * If the required alignment is higher than the chunk size we let it | 
|  | * override that size. | 
|  | */ | 
|  | chunk_max_size = align; | 
|  | } else { | 
|  | chunk_max_size = QEMU_ALIGN_DOWN(HV_BALLOON_HA_CHUNK_PAGES, align); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * hot_add_range->count starts aligned in hv_balloon_hot_add_setup(), | 
|  | * then it is either reduced by subtracting aligned current_count or | 
|  | * further hot-adds are prevented by marking the whole remaining our range | 
|  | * as unusable in hv_balloon_handle_hot_add_response(). | 
|  | */ | 
|  | *current_count = MIN(hot_add_range->count, chunk_max_size); | 
|  |  | 
|  | ha = alloca(ha_size); | 
|  | ha_region = &(&ha->range)[1]; | 
|  | memset(ha, 0, ha_size); | 
|  | ha->hdr.type = DM_MEM_HOT_ADD_REQUEST; | 
|  | ha->hdr.size = ha_size; | 
|  | ha->hdr.trans_id = balloon->trans_id; | 
|  |  | 
|  | ha->range.finfo.start_page = hot_add_range->start; | 
|  | ha->range.finfo.page_cnt = *current_count; | 
|  | ha_region->finfo.start_page = hot_add_range->start; | 
|  | ha_region->finfo.page_cnt = ha->range.finfo.page_cnt; | 
|  |  | 
|  | trace_hv_balloon_outgoing_hot_add(ha->hdr.trans_id, | 
|  | *current_count, hot_add_range->start); | 
|  |  | 
|  | ret = vmbus_channel_send(chan, VMBUS_PACKET_DATA_INBAND, | 
|  | NULL, 0, ha, ha_size, false, | 
|  | ha->hdr.trans_id); | 
|  | if (ret <= 0) { | 
|  | error_report("error %zd when posting hot add msg, expect problems", | 
|  | ret); | 
|  | } | 
|  |  | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_REPLY_WAIT); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_balloon_rb_wait(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | VMBusChannel *chan = hv_balloon_get_channel(balloon); | 
|  | size_t bl_size = sizeof(struct dm_balloon); | 
|  |  | 
|  | assert(balloon->state == S_BALLOON_RB_WAIT); | 
|  |  | 
|  | if (vmbus_channel_reserve(chan, 0, bl_size) < 0) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_BALLOON_POSTING); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_balloon_posting(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | VMBusChannel *chan = hv_balloon_get_channel(balloon); | 
|  | struct dm_balloon bl; | 
|  | size_t bl_size = sizeof(bl); | 
|  | ssize_t ret; | 
|  |  | 
|  | assert(balloon->state == S_BALLOON_POSTING); | 
|  | assert(balloon->balloon_diff > 0); | 
|  |  | 
|  | memset(&bl, 0, sizeof(bl)); | 
|  | bl.hdr.type = DM_BALLOON_REQUEST; | 
|  | bl.hdr.size = bl_size; | 
|  | bl.hdr.trans_id = balloon->trans_id; | 
|  | bl.num_pages = MIN(balloon->balloon_diff, HV_BALLOON_HR_CHUNK_PAGES); | 
|  |  | 
|  | trace_hv_balloon_outgoing_balloon(bl.hdr.trans_id, bl.num_pages, | 
|  | balloon->balloon_diff); | 
|  |  | 
|  | ret = vmbus_channel_send(chan, VMBUS_PACKET_DATA_INBAND, | 
|  | NULL, 0, &bl, bl_size, false, | 
|  | bl.hdr.trans_id); | 
|  | if (ret <= 0) { | 
|  | error_report("error %zd when posting balloon msg, expect problems", | 
|  | ret); | 
|  | } | 
|  |  | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_BALLOON_REPLY_WAIT); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_idle_state_process_target(HvBalloon *balloon, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | bool can_balloon = balloon->caps.cap_bits.balloon; | 
|  | uint64_t ram_size_pages, total_removed; | 
|  |  | 
|  | ram_size_pages = hv_balloon_total_ram(balloon); | 
|  | total_removed = hv_balloon_total_removed_rs(balloon, ram_size_pages); | 
|  |  | 
|  | /* | 
|  | * we need to cache the values computed from the balloon target value when | 
|  | * starting the adjustment procedure in case someone changes the target when | 
|  | * the procedure is in progress | 
|  | */ | 
|  | if (balloon->target > ram_size_pages - total_removed) { | 
|  | bool can_hot_add = balloon->caps.cap_bits.hot_add; | 
|  | uint64_t target_diff = balloon->target - | 
|  | (ram_size_pages - total_removed); | 
|  |  | 
|  | balloon->unballoon_diff = MIN(target_diff, total_removed); | 
|  |  | 
|  | if (can_hot_add) { | 
|  | balloon->hot_add_diff = target_diff - balloon->unballoon_diff; | 
|  | } else { | 
|  | balloon->hot_add_diff = 0; | 
|  | } | 
|  |  | 
|  | if (balloon->unballoon_diff > 0) { | 
|  | assert(can_balloon); | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_UNBALLOON_RB_WAIT); | 
|  | } else if (balloon->hot_add_diff > 0) { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_SETUP); | 
|  | } | 
|  | } else if (can_balloon && | 
|  | balloon->target < ram_size_pages - total_removed) { | 
|  | balloon->balloon_diff = ram_size_pages - total_removed - | 
|  | balloon->target; | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_BALLOON_RB_WAIT); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void hv_balloon_idle_state(HvBalloon *balloon, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | assert(balloon->state == S_IDLE); | 
|  |  | 
|  | if (balloon->target_changed) { | 
|  | balloon->target_changed = false; | 
|  | hv_balloon_idle_state_process_target(balloon, stdesc); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | static const struct { | 
|  | void (*handler)(HvBalloon *balloon, StateDesc *stdesc); | 
|  | } state_handlers[] = { | 
|  | [S_IDLE].handler = hv_balloon_idle_state, | 
|  | [S_BALLOON_POSTING].handler = hv_balloon_balloon_posting, | 
|  | [S_BALLOON_RB_WAIT].handler = hv_balloon_balloon_rb_wait, | 
|  | [S_UNBALLOON_POSTING].handler = hv_balloon_unballoon_posting, | 
|  | [S_UNBALLOON_RB_WAIT].handler = hv_balloon_unballoon_rb_wait, | 
|  | [S_HOT_ADD_SETUP].handler = hv_balloon_hot_add_setup, | 
|  | [S_HOT_ADD_RB_WAIT].handler = hv_balloon_hot_add_rb_wait, | 
|  | [S_HOT_ADD_POSTING].handler = hv_balloon_hot_add_posting, | 
|  | }; | 
|  |  | 
|  | static void hv_balloon_handle_state(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | if (balloon->state >= ARRAY_SIZE(state_handlers) || | 
|  | !state_handlers[balloon->state].handler) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | state_handlers[balloon->state].handler(balloon, stdesc); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_remove_response_insert_range(PageRangeTree tree, | 
|  | const PageRange *range, | 
|  | uint64_t *ctr1, | 
|  | uint64_t *ctr2, | 
|  | uint64_t *ctr3) | 
|  | { | 
|  | uint64_t dupcount, effcount; | 
|  |  | 
|  | if (range->count == 0) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | dupcount = 0; | 
|  | hvb_page_range_tree_insert(tree, range->start, range->count, &dupcount); | 
|  |  | 
|  | assert(dupcount <= range->count); | 
|  | effcount = range->count - dupcount; | 
|  |  | 
|  | *ctr1 += effcount; | 
|  | *ctr2 += effcount; | 
|  | if (ctr3) { | 
|  | *ctr3 += effcount; | 
|  | } | 
|  | } | 
|  |  | 
|  | static void hv_balloon_remove_response_handle_range(HvBalloon *balloon, | 
|  | PageRange *range, | 
|  | bool both, | 
|  | uint64_t *removedctr) | 
|  | { | 
|  | OurRange *our_range = OUR_RANGE(balloon->our_range); | 
|  | PageRangeTree globaltree = | 
|  | both ? balloon->removed_both : balloon->removed_guest; | 
|  | uint64_t *globalctr = | 
|  | both ? &balloon->removed_both_ctr : &balloon->removed_guest_ctr; | 
|  | PageRange rangeeff; | 
|  |  | 
|  | if (range->count == 0) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | trace_hv_balloon_remove_response(range->count, range->start, both); | 
|  |  | 
|  | if (our_range) { | 
|  | /* Includes the not-yet-hot-added and unusable parts. */ | 
|  | rangeeff = our_range->range; | 
|  | } else { | 
|  | rangeeff.start = rangeeff.count = 0; | 
|  | } | 
|  |  | 
|  | if (page_range_intersection_size(range, rangeeff.start, rangeeff.count) > 0) { | 
|  | PageRangeTree ourtree = our_range_get_removed_tree(our_range, both); | 
|  | PageRange rangehole, rangecommon; | 
|  | uint64_t ourremoved = 0; | 
|  |  | 
|  | /* process the hole before our range, if it exists */ | 
|  | page_range_part_before(range, rangeeff.start, &rangehole); | 
|  | hv_balloon_remove_response_insert_range(globaltree, &rangehole, | 
|  | globalctr, removedctr, NULL); | 
|  | if (rangehole.count > 0) { | 
|  | trace_hv_balloon_remove_response_hole(rangehole.count, | 
|  | rangehole.start, | 
|  | range->count, range->start, | 
|  | rangeeff.start, both); | 
|  | } | 
|  |  | 
|  | /* process our part */ | 
|  | page_range_intersect(range, rangeeff.start, rangeeff.count, | 
|  | &rangecommon); | 
|  | hv_balloon_remove_response_insert_range(ourtree, &rangecommon, | 
|  | globalctr, removedctr, | 
|  | &ourremoved); | 
|  | if (rangecommon.count > 0) { | 
|  | trace_hv_balloon_remove_response_common(rangecommon.count, | 
|  | rangecommon.start, | 
|  | range->count, range->start, | 
|  | rangeeff.count, | 
|  | rangeeff.start, ourremoved, | 
|  | both); | 
|  | } | 
|  |  | 
|  | /* calculate what's left after our range */ | 
|  | rangecommon = *range; | 
|  | page_range_part_after(&rangecommon, rangeeff.start, rangeeff.count, | 
|  | range); | 
|  | } | 
|  |  | 
|  | /* process the remainder of the range that lies after our range */ | 
|  | if (range->count > 0) { | 
|  | hv_balloon_remove_response_insert_range(globaltree, range, | 
|  | globalctr, removedctr, NULL); | 
|  | trace_hv_balloon_remove_response_remainder(range->count, range->start, | 
|  | both); | 
|  | range->count = 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | static void hv_balloon_remove_response_handle_pages(HvBalloon *balloon, | 
|  | PageRange *range, | 
|  | uint64_t start, | 
|  | uint64_t count, | 
|  | bool both, | 
|  | uint64_t *removedctr) | 
|  | { | 
|  | assert(count > 0); | 
|  |  | 
|  | /* | 
|  | * if there is an existing range that the new range can't be joined to | 
|  | * dump it into tree(s) | 
|  | */ | 
|  | if (range->count > 0 && !page_range_joinable(range, start, count)) { | 
|  | hv_balloon_remove_response_handle_range(balloon, range, both, | 
|  | removedctr); | 
|  | } | 
|  |  | 
|  | if (range->count == 0) { | 
|  | range->start = start; | 
|  | range->count = count; | 
|  | } else if (page_range_joinable_left(range, start, count)) { | 
|  | range->start = start; | 
|  | range->count += count; | 
|  | } else { /* page_range_joinable_right() */ | 
|  | range->count += count; | 
|  | } | 
|  | } | 
|  |  | 
|  | static gboolean hv_balloon_handle_remove_host_addr_node(gpointer key, | 
|  | gpointer value, | 
|  | gpointer data) | 
|  | { | 
|  | PageRange *range = value; | 
|  | uint64_t pageoff; | 
|  |  | 
|  | for (pageoff = 0; pageoff < range->count; ) { | 
|  | uint64_t addr_64 = (range->start + pageoff) * HV_BALLOON_PAGE_SIZE; | 
|  | void *addr; | 
|  | RAMBlock *rb; | 
|  | ram_addr_t rb_offset; | 
|  | size_t rb_page_size; | 
|  | size_t discard_size; | 
|  |  | 
|  | assert(addr_64 <= UINTPTR_MAX); | 
|  | addr = (void *)((uintptr_t)addr_64); | 
|  | rb = qemu_ram_block_from_host(addr, false, &rb_offset); | 
|  | rb_page_size = qemu_ram_pagesize(rb); | 
|  |  | 
|  | if (rb_page_size != HV_BALLOON_PAGE_SIZE) { | 
|  | /* TODO: these should end in "removed_guest" */ | 
|  | warn_report("guest reported removed page backed by unsupported page size %zu", | 
|  | rb_page_size); | 
|  | pageoff++; | 
|  | continue; | 
|  | } | 
|  |  | 
|  | discard_size = MIN(range->count - pageoff, | 
|  | (rb->max_length - rb_offset) / | 
|  | HV_BALLOON_PAGE_SIZE); | 
|  | discard_size = MAX(discard_size, 1); | 
|  |  | 
|  | if (ram_block_discard_range(rb, rb_offset, discard_size * | 
|  | HV_BALLOON_PAGE_SIZE) != 0) { | 
|  | warn_report("guest reported removed page failed discard"); | 
|  | } | 
|  |  | 
|  | pageoff += discard_size; | 
|  | } | 
|  |  | 
|  | return false; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_remove_host_addr_tree(PageRangeTree tree) | 
|  | { | 
|  | g_tree_foreach(tree.t, hv_balloon_handle_remove_host_addr_node, NULL); | 
|  | } | 
|  |  | 
|  | static int hv_balloon_handle_remove_section(PageRangeTree tree, | 
|  | const MemoryRegionSection *section, | 
|  | uint64_t count) | 
|  | { | 
|  | void *addr = memory_region_get_ram_ptr(section->mr) + | 
|  | section->offset_within_region; | 
|  | uint64_t addr_page; | 
|  |  | 
|  | assert(count > 0); | 
|  |  | 
|  | if ((uintptr_t)addr % HV_BALLOON_PAGE_SIZE) { | 
|  | warn_report("guest reported removed pages at an unaligned host addr %p", | 
|  | addr); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | addr_page = (uintptr_t)addr / HV_BALLOON_PAGE_SIZE; | 
|  | hvb_page_range_tree_insert(tree, addr_page, count, NULL); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_remove_ranges(HvBalloon *balloon, | 
|  | union dm_mem_page_range ranges[], | 
|  | uint32_t count) | 
|  | { | 
|  | uint64_t removedcnt; | 
|  | PageRangeTree removed_host_addr; | 
|  | PageRange range_guest, range_both; | 
|  |  | 
|  | hvb_page_range_tree_init(&removed_host_addr); | 
|  | range_guest.count = range_both.count = removedcnt = 0; | 
|  | for (unsigned int ctr = 0; ctr < count; ctr++) { | 
|  | union dm_mem_page_range *mr = &ranges[ctr]; | 
|  | hwaddr pa; | 
|  | MemoryRegionSection section; | 
|  |  | 
|  | for (unsigned int offset = 0; offset < mr->finfo.page_cnt; ) { | 
|  | int ret; | 
|  | uint64_t pageno = mr->finfo.start_page + offset; | 
|  | uint64_t pagecnt = 1; | 
|  |  | 
|  | pa = (hwaddr)pageno << HV_BALLOON_PFN_SHIFT; | 
|  | section = memory_region_find(get_system_memory(), pa, | 
|  | (mr->finfo.page_cnt - offset) * | 
|  | HV_BALLOON_PAGE_SIZE); | 
|  | if (!section.mr) { | 
|  | warn_report("guest reported removed page %"PRIu64" not found in RAM", | 
|  | pageno); | 
|  | ret = -EINVAL; | 
|  | goto finish_page; | 
|  | } | 
|  |  | 
|  | pagecnt = int128_get64(section.size) / HV_BALLOON_PAGE_SIZE; | 
|  | if (pagecnt <= 0) { | 
|  | warn_report("guest reported removed page %"PRIu64" in a section smaller than page size", | 
|  | pageno); | 
|  | pagecnt = 1; /* skip the whole page */ | 
|  | ret = -EINVAL; | 
|  | goto finish_page; | 
|  | } | 
|  |  | 
|  | if (!memory_region_is_ram(section.mr) || | 
|  | memory_region_is_rom(section.mr) || | 
|  | memory_region_is_romd(section.mr)) { | 
|  | warn_report("guest reported removed page %"PRIu64" in a section that is not an ordinary RAM", | 
|  | pageno); | 
|  | ret = -EINVAL; | 
|  | goto finish_page; | 
|  | } | 
|  |  | 
|  | ret = hv_balloon_handle_remove_section(removed_host_addr, §ion, | 
|  | pagecnt); | 
|  |  | 
|  | finish_page: | 
|  | if (ret == 0) { | 
|  | hv_balloon_remove_response_handle_pages(balloon, | 
|  | &range_both, | 
|  | pageno, pagecnt, | 
|  | true, &removedcnt); | 
|  | } else { | 
|  | hv_balloon_remove_response_handle_pages(balloon, | 
|  | &range_guest, | 
|  | pageno, pagecnt, | 
|  | false, &removedcnt); | 
|  | } | 
|  |  | 
|  | if (section.mr) { | 
|  | memory_region_unref(section.mr); | 
|  | } | 
|  |  | 
|  | offset += pagecnt; | 
|  | } | 
|  | } | 
|  |  | 
|  | hv_balloon_remove_response_handle_range(balloon, &range_both, true, | 
|  | &removedcnt); | 
|  | hv_balloon_remove_response_handle_range(balloon, &range_guest, false, | 
|  | &removedcnt); | 
|  |  | 
|  | hv_balloon_handle_remove_host_addr_tree(removed_host_addr); | 
|  | hvb_page_range_tree_destroy(&removed_host_addr); | 
|  |  | 
|  | if (removedcnt > balloon->balloon_diff) { | 
|  | warn_report("guest reported more pages removed than currently pending (%"PRIu64" vs %"PRIu64")", | 
|  | removedcnt, balloon->balloon_diff); | 
|  | balloon->balloon_diff = 0; | 
|  | } else { | 
|  | balloon->balloon_diff -= removedcnt; | 
|  | } | 
|  | } | 
|  |  | 
|  | static bool hv_balloon_handle_msg_size(HvBalloonReq *req, size_t minsize, | 
|  | const char *msgname) | 
|  | { | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | uint32_t msglen = vmreq->msglen; | 
|  |  | 
|  | if (msglen >= minsize) { | 
|  | return true; | 
|  | } | 
|  |  | 
|  | warn_report("%s message too short (%u vs %zu), ignoring", msgname, | 
|  | (unsigned int)msglen, minsize); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_version_request(HvBalloon *balloon, | 
|  | HvBalloonReq *req, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | struct dm_version_request *msgVr = vmreq->msg; | 
|  | struct dm_version_response respVr; | 
|  |  | 
|  | if (balloon->state != S_VERSION) { | 
|  | warn_report("unexpected DM_VERSION_REQUEST in %d state", | 
|  | balloon->state); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (!hv_balloon_handle_msg_size(req, sizeof(*msgVr), | 
|  | "DM_VERSION_REQUEST")) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | trace_hv_balloon_incoming_version(msgVr->version.major_version, | 
|  | msgVr->version.minor_version); | 
|  |  | 
|  | memset(&respVr, 0, sizeof(respVr)); | 
|  | respVr.hdr.type = DM_VERSION_RESPONSE; | 
|  | respVr.hdr.size = sizeof(respVr); | 
|  | respVr.hdr.trans_id = msgVr->hdr.trans_id; | 
|  | respVr.is_accepted = msgVr->version.version >= DYNMEM_PROTOCOL_VERSION_1 && | 
|  | msgVr->version.version <= DYNMEM_PROTOCOL_VERSION_3; | 
|  |  | 
|  | hv_balloon_send_packet(vmreq->chan, (struct dm_message *)&respVr); | 
|  |  | 
|  | if (respVr.is_accepted) { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_CAPS); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_caps_report(HvBalloon *balloon, | 
|  | HvBalloonReq *req, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | struct dm_capabilities *msgCap = vmreq->msg; | 
|  | struct dm_capabilities_resp_msg respCap; | 
|  |  | 
|  | if (balloon->state != S_CAPS) { | 
|  | warn_report("unexpected DM_CAPABILITIES_REPORT in %d state", | 
|  | balloon->state); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (!hv_balloon_handle_msg_size(req, sizeof(*msgCap), | 
|  | "DM_CAPABILITIES_REPORT")) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | trace_hv_balloon_incoming_caps(msgCap->caps.caps); | 
|  | balloon->caps = msgCap->caps; | 
|  |  | 
|  | memset(&respCap, 0, sizeof(respCap)); | 
|  | respCap.hdr.type = DM_CAPABILITIES_RESPONSE; | 
|  | respCap.hdr.size = sizeof(respCap); | 
|  | respCap.hdr.trans_id = msgCap->hdr.trans_id; | 
|  | respCap.is_accepted = 1; | 
|  | respCap.hot_remove = 1; | 
|  | respCap.suppress_pressure_reports = !balloon->status_report.enabled; | 
|  | hv_balloon_send_packet(vmreq->chan, (struct dm_message *)&respCap); | 
|  |  | 
|  | timer_mod(&balloon->post_init_timer, | 
|  | qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + | 
|  | HV_BALLOON_POST_INIT_WAIT); | 
|  |  | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_POST_INIT_WAIT); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_status_report(HvBalloon *balloon, | 
|  | HvBalloonReq *req) | 
|  | { | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | struct dm_status *msgStatus = vmreq->msg; | 
|  |  | 
|  | if (!hv_balloon_handle_msg_size(req, sizeof(*msgStatus), | 
|  | "DM_STATUS_REPORT")) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (!balloon->status_report.enabled) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | balloon->status_report.committed = msgStatus->num_committed; | 
|  | balloon->status_report.committed *= HV_BALLOON_PAGE_SIZE; | 
|  | balloon->status_report.available = msgStatus->num_avail; | 
|  | balloon->status_report.available *= HV_BALLOON_PAGE_SIZE; | 
|  | balloon->status_report.received = true; | 
|  |  | 
|  | qapi_event_send_hv_balloon_status_report(balloon->status_report.committed, | 
|  | balloon->status_report.available); | 
|  | } | 
|  |  | 
|  | HvBalloonInfo *qmp_query_hv_balloon_status_report(Error **errp) | 
|  | { | 
|  | HvBalloon *balloon; | 
|  | HvBalloonInfo *info; | 
|  |  | 
|  | balloon = HV_BALLOON(object_resolve_path_type("", TYPE_HV_BALLOON, NULL)); | 
|  | if (!balloon) { | 
|  | error_setg(errp, "no %s device present", TYPE_HV_BALLOON); | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | if (!balloon->status_report.enabled) { | 
|  | error_setg(errp, "guest memory status reporting not enabled"); | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | if (!balloon->status_report.received) { | 
|  | error_setg(errp, "no guest memory status report received yet"); | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | info = g_malloc0(sizeof(*info)); | 
|  | info->committed = balloon->status_report.committed; | 
|  | info->available = balloon->status_report.available; | 
|  | return info; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_unballoon_response(HvBalloon *balloon, | 
|  | HvBalloonReq *req, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | struct dm_unballoon_response *msgUrR = vmreq->msg; | 
|  |  | 
|  | if (balloon->state != S_UNBALLOON_REPLY_WAIT) { | 
|  | warn_report("unexpected DM_UNBALLOON_RESPONSE in %d state", | 
|  | balloon->state); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (!hv_balloon_handle_msg_size(req, sizeof(*msgUrR), | 
|  | "DM_UNBALLOON_RESPONSE")) | 
|  | return; | 
|  |  | 
|  | trace_hv_balloon_incoming_unballoon(msgUrR->hdr.trans_id); | 
|  |  | 
|  | balloon->trans_id++; | 
|  |  | 
|  | if (balloon->hot_add_diff > 0) { | 
|  | bool can_hot_add = balloon->caps.cap_bits.hot_add; | 
|  |  | 
|  | assert(can_hot_add); | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_SETUP); | 
|  | } else { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_IDLE); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_hot_add_response(HvBalloon *balloon, | 
|  | HvBalloonReq *req, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | PageRange *hot_add_range = &balloon->hot_add_range; | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | struct dm_hot_add_response *msgHaR = vmreq->msg; | 
|  | OurRange *our_range; | 
|  |  | 
|  | if (balloon->state != S_HOT_ADD_REPLY_WAIT) { | 
|  | warn_report("unexpected DM_HOT_ADD_RESPONSE in %d state", | 
|  | balloon->state); | 
|  | return; | 
|  | } | 
|  |  | 
|  | assert(balloon->our_range); | 
|  | our_range = OUR_RANGE(balloon->our_range); | 
|  |  | 
|  | if (!hv_balloon_handle_msg_size(req, sizeof(*msgHaR), | 
|  | "DM_HOT_ADD_RESPONSE")) | 
|  | return; | 
|  |  | 
|  | trace_hv_balloon_incoming_hot_add(msgHaR->hdr.trans_id, msgHaR->result, | 
|  | msgHaR->page_count); | 
|  |  | 
|  | balloon->trans_id++; | 
|  |  | 
|  | if (msgHaR->result) { | 
|  | if (msgHaR->page_count > balloon->ha_current_count) { | 
|  | warn_report("DM_HOT_ADD_RESPONSE page count higher than requested (%"PRIu32" vs %"PRIu64")", | 
|  | msgHaR->page_count, balloon->ha_current_count); | 
|  | msgHaR->page_count = balloon->ha_current_count; | 
|  | } | 
|  |  | 
|  | hvb_our_range_mark_added(our_range, msgHaR->page_count); | 
|  | hot_add_range->start += msgHaR->page_count; | 
|  | hot_add_range->count -= msgHaR->page_count; | 
|  | } | 
|  |  | 
|  | if (!msgHaR->result || msgHaR->page_count < balloon->ha_current_count) { | 
|  | /* | 
|  | * the current planned range was only partially hot-added, take note | 
|  | * how much of it remains and don't attempt any further hot adds | 
|  | */ | 
|  | our_range_mark_remaining_unusable(our_range); | 
|  |  | 
|  | goto ret_idle; | 
|  | } | 
|  |  | 
|  | /* any pages remaining to hot-add in our range? */ | 
|  | if (hot_add_range->count > 0) { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_RB_WAIT); | 
|  | return; | 
|  | } | 
|  |  | 
|  | ret_idle: | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_IDLE); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_balloon_response(HvBalloon *balloon, | 
|  | HvBalloonReq *req, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | struct dm_balloon_response *msgBR = vmreq->msg; | 
|  |  | 
|  | if (balloon->state != S_BALLOON_REPLY_WAIT) { | 
|  | warn_report("unexpected DM_BALLOON_RESPONSE in %d state", | 
|  | balloon->state); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (!hv_balloon_handle_msg_size(req, sizeof(*msgBR), | 
|  | "DM_BALLOON_RESPONSE")) | 
|  | return; | 
|  |  | 
|  | trace_hv_balloon_incoming_balloon(msgBR->hdr.trans_id, msgBR->range_count, | 
|  | msgBR->more_pages); | 
|  |  | 
|  | if (vmreq->msglen < sizeof(*msgBR) + | 
|  | (uint64_t)sizeof(msgBR->range_array[0]) * msgBR->range_count) { | 
|  | warn_report("DM_BALLOON_RESPONSE too short for the range count"); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (msgBR->range_count == 0) { | 
|  | /* The guest is already at its minimum size */ | 
|  | balloon->balloon_diff = 0; | 
|  | goto ret_end_trans; | 
|  | } else { | 
|  | hv_balloon_handle_remove_ranges(balloon, | 
|  | msgBR->range_array, | 
|  | msgBR->range_count); | 
|  | } | 
|  |  | 
|  | /* More responses expected? */ | 
|  | if (msgBR->more_pages) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | ret_end_trans: | 
|  | balloon->trans_id++; | 
|  |  | 
|  | if (balloon->balloon_diff > 0) { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_BALLOON_RB_WAIT); | 
|  | } else { | 
|  | HV_BALLOON_STATE_DESC_SET(stdesc, S_IDLE); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void hv_balloon_handle_packet(HvBalloon *balloon, HvBalloonReq *req, | 
|  | StateDesc *stdesc) | 
|  | { | 
|  | VMBusChanReq *vmreq = &req->vmreq; | 
|  | struct dm_message *msg = vmreq->msg; | 
|  |  | 
|  | if (vmreq->msglen < sizeof(msg->hdr)) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | switch (msg->hdr.type) { | 
|  | case DM_VERSION_REQUEST: | 
|  | hv_balloon_handle_version_request(balloon, req, stdesc); | 
|  | break; | 
|  |  | 
|  | case DM_CAPABILITIES_REPORT: | 
|  | hv_balloon_handle_caps_report(balloon, req, stdesc); | 
|  | break; | 
|  |  | 
|  | case DM_STATUS_REPORT: | 
|  | hv_balloon_handle_status_report(balloon, req); | 
|  | break; | 
|  |  | 
|  | case DM_MEM_HOT_ADD_RESPONSE: | 
|  | hv_balloon_handle_hot_add_response(balloon, req, stdesc); | 
|  | break; | 
|  |  | 
|  | case DM_UNBALLOON_RESPONSE: | 
|  | hv_balloon_handle_unballoon_response(balloon, req, stdesc); | 
|  | break; | 
|  |  | 
|  | case DM_BALLOON_RESPONSE: | 
|  | hv_balloon_handle_balloon_response(balloon, req, stdesc); | 
|  | break; | 
|  |  | 
|  | default: | 
|  | warn_report("unknown DM message %u", msg->hdr.type); | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | static bool hv_balloon_recv_channel(HvBalloon *balloon, StateDesc *stdesc) | 
|  | { | 
|  | VMBusChannel *chan; | 
|  | HvBalloonReq *req; | 
|  |  | 
|  | if (balloon->state == S_WAIT_RESET || | 
|  | balloon->state == S_POST_RESET_CLOSED) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | chan = hv_balloon_get_channel(balloon); | 
|  | if (vmbus_channel_recv_start(chan)) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | while ((req = vmbus_channel_recv_peek(chan, sizeof(*req)))) { | 
|  | hv_balloon_handle_packet(balloon, req, stdesc); | 
|  | vmbus_free_req(req); | 
|  | vmbus_channel_recv_pop(chan); | 
|  |  | 
|  | if (stdesc->state != S_NO_CHANGE) { | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | return vmbus_channel_recv_done(chan) > 0; | 
|  | } | 
|  |  | 
|  | /* old state handler -> new state transition (potential) */ | 
|  | static bool hv_balloon_event_loop_state(HvBalloon *balloon) | 
|  | { | 
|  | StateDesc state_new = HV_BALLOON_STATE_DESC_INIT; | 
|  |  | 
|  | hv_balloon_handle_state(balloon, &state_new); | 
|  | return hv_balloon_state_set(balloon, state_new.state, state_new.desc); | 
|  | } | 
|  |  | 
|  | /* VMBus message -> new state transition (potential) */ | 
|  | static bool hv_balloon_event_loop_recv(HvBalloon *balloon) | 
|  | { | 
|  | StateDesc state_new = HV_BALLOON_STATE_DESC_INIT; | 
|  | bool any_recv, state_changed; | 
|  |  | 
|  | any_recv = hv_balloon_recv_channel(balloon, &state_new); | 
|  | state_changed = hv_balloon_state_set(balloon, | 
|  | state_new.state, state_new.desc); | 
|  |  | 
|  | return state_changed || any_recv; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_event_loop(HvBalloon *balloon) | 
|  | { | 
|  | bool state_repeat, recv_repeat; | 
|  |  | 
|  | do { | 
|  | state_repeat = hv_balloon_event_loop_state(balloon); | 
|  | recv_repeat = hv_balloon_event_loop_recv(balloon); | 
|  | } while (state_repeat || recv_repeat); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_vmdev_chan_notify(VMBusChannel *chan) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(vmbus_channel_device(chan)); | 
|  |  | 
|  | hv_balloon_event_loop(balloon); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_stat(void *opaque, BalloonInfo *info) | 
|  | { | 
|  | HvBalloon *balloon = opaque; | 
|  | info->actual = (hv_balloon_total_ram(balloon) - balloon->removed_both_ctr) | 
|  | << HV_BALLOON_PFN_SHIFT; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_to_target(void *opaque, ram_addr_t target) | 
|  | { | 
|  | HvBalloon *balloon = opaque; | 
|  | uint64_t target_pages = target >> HV_BALLOON_PFN_SHIFT; | 
|  |  | 
|  | if (!target_pages) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * always set target_changed, even with unchanged target, as the user | 
|  | * might be asking us to try again reaching it | 
|  | */ | 
|  | balloon->target = target_pages; | 
|  | balloon->target_changed = true; | 
|  |  | 
|  | hv_balloon_event_loop(balloon); | 
|  | } | 
|  |  | 
|  | static int hv_balloon_vmdev_open_channel(VMBusChannel *chan) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(vmbus_channel_device(chan)); | 
|  |  | 
|  | if (balloon->state != S_POST_RESET_CLOSED) { | 
|  | warn_report("guest trying to open a DM channel in invalid %d state", | 
|  | balloon->state); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | HV_BALLOON_SET_STATE(balloon, S_VERSION); | 
|  | hv_balloon_event_loop(balloon); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_vmdev_close_channel(VMBusChannel *chan) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(vmbus_channel_device(chan)); | 
|  |  | 
|  | timer_del(&balloon->post_init_timer); | 
|  |  | 
|  | /* Don't report stale data */ | 
|  | balloon->status_report.received = false; | 
|  |  | 
|  | HV_BALLOON_SET_STATE(balloon, S_WAIT_RESET); | 
|  | hv_balloon_event_loop(balloon); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_post_init_timer(void *opaque) | 
|  | { | 
|  | HvBalloon *balloon = opaque; | 
|  |  | 
|  | if (balloon->state != S_POST_INIT_WAIT) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | HV_BALLOON_SET_STATE(balloon, S_IDLE); | 
|  | hv_balloon_event_loop(balloon); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_system_reset_unrealize_common(HvBalloon *balloon) | 
|  | { | 
|  | g_clear_pointer(&balloon->our_range, hvb_our_range_memslots_free); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_system_reset(void *opaque) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(opaque); | 
|  |  | 
|  | hv_balloon_system_reset_unrealize_common(balloon); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_ensure_mr(HvBalloon *balloon) | 
|  | { | 
|  | MemoryRegion *hostmem_mr; | 
|  |  | 
|  | assert(balloon->hostmem); | 
|  |  | 
|  | if (balloon->mr) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | hostmem_mr = host_memory_backend_get_memory(balloon->hostmem); | 
|  |  | 
|  | balloon->mr = g_new0(MemoryRegion, 1); | 
|  | memory_region_init(balloon->mr, OBJECT(balloon), TYPE_HV_BALLOON, | 
|  | memory_region_size(hostmem_mr)); | 
|  |  | 
|  | /* | 
|  | * The VM can indicate an alignment up to 32 GiB. Memory device core can | 
|  | * usually only handle/guarantee 1 GiB alignment. The user will have to | 
|  | * specify a larger maxmem eventually. | 
|  | * | 
|  | * The memory device core will warn the user in case maxmem might have to be | 
|  | * increased and will fail plugging the device if there is not sufficient | 
|  | * space after alignment. | 
|  | * | 
|  | * TODO: we could do the alignment ourselves in a slightly bigger region. | 
|  | * But this feels better, although the warning might be annoying. Maybe | 
|  | * we can optimize that in the future (e.g., with such a device on the | 
|  | * cmdline place/size the device memory region differently. | 
|  | */ | 
|  | balloon->mr->align = MAX(32 * GiB, memory_region_get_alignment(hostmem_mr)); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_free_mr(HvBalloon *balloon) | 
|  | { | 
|  | if (!balloon->mr) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | object_unparent(OBJECT(balloon->mr)); | 
|  | g_clear_pointer(&balloon->mr, g_free); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_vmdev_realize(VMBusDevice *vdev, Error **errp) | 
|  | { | 
|  | ERRP_GUARD(); | 
|  | HvBalloon *balloon = HV_BALLOON(vdev); | 
|  | int ret; | 
|  |  | 
|  | balloon->state = S_WAIT_RESET; | 
|  |  | 
|  | ret = qemu_add_balloon_handler(hv_balloon_to_target, hv_balloon_stat, | 
|  | balloon); | 
|  | if (ret < 0) { | 
|  | /* This also protects against having multiple hv-balloon instances */ | 
|  | error_setg(errp, "Only one balloon device is supported"); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (balloon->hostmem) { | 
|  | if (host_memory_backend_is_mapped(balloon->hostmem)) { | 
|  | Object *obj = OBJECT(balloon->hostmem); | 
|  |  | 
|  | error_setg(errp, "'%s' property specifies a busy memdev: %s", | 
|  | HV_BALLOON_MEMDEV_PROP, | 
|  | object_get_canonical_path_component(obj)); | 
|  | goto out_balloon_handler; | 
|  | } | 
|  |  | 
|  | hv_balloon_ensure_mr(balloon); | 
|  |  | 
|  | /* This is rather unlikely to happen, but let's still check for it. */ | 
|  | if (!QEMU_IS_ALIGNED(memory_region_size(balloon->mr), | 
|  | HV_BALLOON_PAGE_SIZE)) { | 
|  | error_setg(errp, "'%s' property memdev size has to be a multiple of 0x%" PRIx64, | 
|  | HV_BALLOON_MEMDEV_PROP, (uint64_t)HV_BALLOON_PAGE_SIZE); | 
|  | goto out_balloon_handler; | 
|  | } | 
|  |  | 
|  | host_memory_backend_set_mapped(balloon->hostmem, true); | 
|  | vmstate_register_ram(host_memory_backend_get_memory(balloon->hostmem), | 
|  | DEVICE(balloon)); | 
|  | } else if (balloon->addr) { | 
|  | error_setg(errp, "'%s' property must not be set without a memdev", | 
|  | HV_BALLOON_MEMDEV_PROP); | 
|  | goto out_balloon_handler; | 
|  | } | 
|  |  | 
|  | timer_init_ms(&balloon->post_init_timer, QEMU_CLOCK_VIRTUAL, | 
|  | hv_balloon_post_init_timer, balloon); | 
|  |  | 
|  | qemu_register_reset(hv_balloon_system_reset, balloon); | 
|  |  | 
|  | return; | 
|  |  | 
|  | out_balloon_handler: | 
|  | qemu_remove_balloon_handler(balloon); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * VMBus device reset has to be implemented in case the guest decides to | 
|  | * disconnect and reconnect to the VMBus without rebooting the whole system. | 
|  | * | 
|  | * However, the hot-added memory can't be removed here as Windows keeps on using | 
|  | * it until the system is restarted, even after disconnecting from the VMBus. | 
|  | */ | 
|  | static void hv_balloon_vmdev_reset(VMBusDevice *vdev) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(vdev); | 
|  |  | 
|  | if (balloon->state == S_POST_RESET_CLOSED) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (balloon->our_range) { | 
|  | hvb_our_range_clear_removed_trees(OUR_RANGE(balloon->our_range)); | 
|  | } | 
|  |  | 
|  | hvb_page_range_tree_destroy(&balloon->removed_guest); | 
|  | hvb_page_range_tree_destroy(&balloon->removed_both); | 
|  | hvb_page_range_tree_init(&balloon->removed_guest); | 
|  | hvb_page_range_tree_init(&balloon->removed_both); | 
|  |  | 
|  | balloon->trans_id = 0; | 
|  | balloon->removed_guest_ctr = 0; | 
|  | balloon->removed_both_ctr = 0; | 
|  |  | 
|  | HV_BALLOON_SET_STATE(balloon, S_POST_RESET_CLOSED); | 
|  | hv_balloon_event_loop(balloon); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Clean up things that were (possibly) allocated pre-realization, for example | 
|  | * from memory_device_pre_plug(), so we don't leak them if the device don't | 
|  | * actually get realized in the end. | 
|  | */ | 
|  | static void hv_balloon_unrealize_finalize_common(HvBalloon *balloon) | 
|  | { | 
|  | hv_balloon_free_mr(balloon); | 
|  | balloon->addr = 0; | 
|  |  | 
|  | balloon->memslot_count = 0; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_vmdev_unrealize(VMBusDevice *vdev) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(vdev); | 
|  |  | 
|  | qemu_unregister_reset(hv_balloon_system_reset, balloon); | 
|  |  | 
|  | hv_balloon_system_reset_unrealize_common(balloon); | 
|  |  | 
|  | qemu_remove_balloon_handler(balloon); | 
|  |  | 
|  | if (balloon->hostmem) { | 
|  | vmstate_unregister_ram(host_memory_backend_get_memory(balloon->hostmem), | 
|  | DEVICE(balloon)); | 
|  | host_memory_backend_set_mapped(balloon->hostmem, false); | 
|  | } | 
|  |  | 
|  | hvb_page_range_tree_destroy(&balloon->removed_guest); | 
|  | hvb_page_range_tree_destroy(&balloon->removed_both); | 
|  |  | 
|  | hv_balloon_unrealize_finalize_common(balloon); | 
|  | } | 
|  |  | 
|  | static uint64_t hv_balloon_md_get_addr(const MemoryDeviceState *md) | 
|  | { | 
|  | return object_property_get_uint(OBJECT(md), HV_BALLOON_ADDR_PROP, | 
|  | &error_abort); | 
|  | } | 
|  |  | 
|  | static void hv_balloon_md_set_addr(MemoryDeviceState *md, uint64_t addr, | 
|  | Error **errp) | 
|  | { | 
|  | object_property_set_uint(OBJECT(md), HV_BALLOON_ADDR_PROP, addr, errp); | 
|  | } | 
|  |  | 
|  | static MemoryRegion *hv_balloon_md_get_memory_region(MemoryDeviceState *md, | 
|  | Error **errp) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(md); | 
|  |  | 
|  | if (!balloon->hostmem) { | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | hv_balloon_ensure_mr(balloon); | 
|  |  | 
|  | return balloon->mr; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_md_fill_device_info(const MemoryDeviceState *md, | 
|  | MemoryDeviceInfo *info) | 
|  | { | 
|  | HvBalloonDeviceInfo *hi = g_new0(HvBalloonDeviceInfo, 1); | 
|  | const HvBalloon *balloon = HV_BALLOON(md); | 
|  | DeviceState *dev = DEVICE(md); | 
|  |  | 
|  | if (dev->id) { | 
|  | hi->id = g_strdup(dev->id); | 
|  | } | 
|  |  | 
|  | if (balloon->hostmem) { | 
|  | hi->memdev = object_get_canonical_path(OBJECT(balloon->hostmem)); | 
|  | hi->memaddr = balloon->addr; | 
|  | hi->has_memaddr = true; | 
|  | hi->max_size = memory_region_size(balloon->mr); | 
|  | /* TODO: expose current provided size or something else? */ | 
|  | } else { | 
|  | hi->max_size = 0; | 
|  | } | 
|  |  | 
|  | info->u.hv_balloon.data = hi; | 
|  | info->type = MEMORY_DEVICE_INFO_KIND_HV_BALLOON; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_decide_memslots(MemoryDeviceState *md, | 
|  | unsigned int limit) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(md); | 
|  | MemoryRegion *hostmem_mr; | 
|  | uint64_t region_size, memslot_size, memslots; | 
|  |  | 
|  | /* We're called exactly once, before realizing the device. */ | 
|  | assert(!balloon->memslot_count); | 
|  |  | 
|  | /* We should not be called if we don't have a memory backend */ | 
|  | assert(balloon->hostmem); | 
|  |  | 
|  | hostmem_mr = host_memory_backend_get_memory(balloon->hostmem); | 
|  | region_size = memory_region_size(hostmem_mr); | 
|  |  | 
|  | assert(region_size > 0); | 
|  | memslot_size = QEMU_ALIGN_UP(region_size / limit, | 
|  | HV_BALLOON_HA_MEMSLOT_SIZE_ALIGN); | 
|  | memslots = QEMU_ALIGN_UP(region_size, memslot_size) / memslot_size; | 
|  |  | 
|  | if (memslots > 1) { | 
|  | balloon->memslot_size = memslot_size; | 
|  | } else { | 
|  | balloon->memslot_size = region_size; | 
|  | } | 
|  |  | 
|  | assert(memslots <= UINT_MAX); | 
|  | balloon->memslot_count = memslots; | 
|  | } | 
|  |  | 
|  | static unsigned int hv_balloon_get_memslots(MemoryDeviceState *md) | 
|  | { | 
|  | const HvBalloon *balloon = HV_BALLOON(md); | 
|  |  | 
|  | /* We're called after setting the suggested limit. */ | 
|  | assert(balloon->memslot_count > 0); | 
|  |  | 
|  | return balloon->memslot_count; | 
|  | } | 
|  |  | 
|  | static void hv_balloon_init(Object *obj) | 
|  | { | 
|  | } | 
|  |  | 
|  | static void hv_balloon_finalize(Object *obj) | 
|  | { | 
|  | HvBalloon *balloon = HV_BALLOON(obj); | 
|  |  | 
|  | hv_balloon_unrealize_finalize_common(balloon); | 
|  | } | 
|  |  | 
|  | static Property hv_balloon_properties[] = { | 
|  | DEFINE_PROP_BOOL("status-report", HvBalloon, | 
|  | status_report.enabled, false), | 
|  |  | 
|  | /* MEMORY_DEVICE props */ | 
|  | DEFINE_PROP_LINK(HV_BALLOON_MEMDEV_PROP, HvBalloon, hostmem, | 
|  | TYPE_MEMORY_BACKEND, HostMemoryBackend *), | 
|  | DEFINE_PROP_UINT64(HV_BALLOON_ADDR_PROP, HvBalloon, addr, 0), | 
|  |  | 
|  | DEFINE_PROP_END_OF_LIST(), | 
|  | }; | 
|  |  | 
|  | static void hv_balloon_class_init(ObjectClass *klass, void *data) | 
|  | { | 
|  | DeviceClass *dc = DEVICE_CLASS(klass); | 
|  | VMBusDeviceClass *vdc = VMBUS_DEVICE_CLASS(klass); | 
|  | MemoryDeviceClass *mdc = MEMORY_DEVICE_CLASS(klass); | 
|  |  | 
|  | device_class_set_props(dc, hv_balloon_properties); | 
|  | qemu_uuid_parse(HV_BALLOON_GUID, &vdc->classid); | 
|  | set_bit(DEVICE_CATEGORY_MISC, dc->categories); | 
|  |  | 
|  | vdc->vmdev_realize = hv_balloon_vmdev_realize; | 
|  | vdc->vmdev_unrealize = hv_balloon_vmdev_unrealize; | 
|  | vdc->vmdev_reset = hv_balloon_vmdev_reset; | 
|  | vdc->open_channel = hv_balloon_vmdev_open_channel; | 
|  | vdc->close_channel = hv_balloon_vmdev_close_channel; | 
|  | vdc->chan_notify_cb = hv_balloon_vmdev_chan_notify; | 
|  |  | 
|  | mdc->get_addr = hv_balloon_md_get_addr; | 
|  | mdc->set_addr = hv_balloon_md_set_addr; | 
|  | mdc->get_plugged_size = memory_device_get_region_size; | 
|  | mdc->get_memory_region = hv_balloon_md_get_memory_region; | 
|  | mdc->decide_memslots = hv_balloon_decide_memslots; | 
|  | mdc->get_memslots = hv_balloon_get_memslots; | 
|  | mdc->fill_device_info = hv_balloon_md_fill_device_info; | 
|  | } |