@@ -46,3 +46,6 @@ config FUZZ
config VFIO_USER_SERVER_ALLOWED
bool
imply VFIO_USER_SERVER
+
+config HV_BALLOON_POSSIBLE
+ bool
@@ -286,6 +286,7 @@ bsd_user=""
pie=""
coroutine=""
plugins="$default_feature"
+hv_balloon="$default_feature"
meson=""
ninja=""
bindir="bin"
@@ -897,6 +898,10 @@ for opt do
;;
--enable-jemalloc) meson_option_parse --enable-malloc=jemalloc jemalloc
;;
+ --enable-hv-balloon) hv_balloon=yes
+ ;;
+ --disable-hv-balloon) hv_balloon=no
+ ;;
# everything else has the same name in configure and meson
--*) meson_option_parse "$opt" "$optarg"
;;
@@ -1050,6 +1055,7 @@ cat << EOF
debug-info debugging information
safe-stack SafeStack Stack Smash Protection. Depends on
clang/llvm >= 3.7 and requires coroutine backend ucontext.
+ hv-balloon hv-balloon driver where supported (requires Glib 2.68+ GTree API)
NOTE: The object files are built at the place where configure is launched
EOF
@@ -1777,6 +1783,32 @@ EOF
fi
fi
+##########################################
+# check for hv-balloon
+
+if test "$hv_balloon" != "no"; then
+ cat > $TMPC << EOF
+#include <string.h>
+#include <gmodule.h>
+int main(void) {
+ GTree *tree;
+
+ tree = g_tree_new((GCompareFunc)strcmp);
+ (void)g_tree_node_first(tree);
+ g_tree_destroy(tree);
+ return 0;
+}
+EOF
+ if compile_prog "$glib_cflags" "$glib_libs" ; then
+ hv_balloon=yes
+ else
+ if test "$hv_balloon" = "yes" ; then
+ feature_not_found "hv-balloon" "Update Glib"
+ fi
+ hv_balloon="no"
+ fi
+fi
+
##########################################
# functions to probe cross compilers
@@ -2389,6 +2421,10 @@ if test "$have_tsan" = "yes" && test "$have_tsan_iface_fiber" = "yes" ; then
echo "CONFIG_TSAN=y" >> $config_host_mak
fi
+if test "$hv_balloon" = "yes" ; then
+ echo "CONFIG_HV_BALLOON_POSSIBLE=y" >> $config_host_mak
+fi
+
if test "$plugins" = "yes" ; then
echo "CONFIG_PLUGIN=y" >> $config_host_mak
fi
@@ -16,3 +16,8 @@ config SYNDBG
bool
default y
depends on VMBUS
+
+config HV_BALLOON
+ bool
+ default y
+ depends on HV_BALLOON_POSSIBLE && VMBUS && HAPVDIMM
new file mode 100644
@@ -0,0 +1,2185 @@
+/*
+ * 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 "qemu/osdep.h"
+
+#include "exec/address-spaces.h"
+#include "exec/cpu-common.h"
+#include "exec/memory.h"
+#include "exec/ramblock.h"
+#include "hw/boards.h"
+#include "hw/hyperv/dynmem-proto.h"
+#include "hw/hyperv/vmbus.h"
+#include "hw/mem/hapvdimm.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/qmp/qdict.h"
+#include "qemu/error-report.h"
+#include "qemu/module.h"
+#include "qemu/units.h"
+#include "qemu/timer.h"
+#include "sysemu/balloon.h"
+#include "sysemu/reset.h"
+#include "trace.h"
+
+/*
+ * temporarily avoid warnings about enhanced GTree API usage requiring a
+ * too recent Glib version until GLIB_VERSION_MAX_ALLOWED finally reaches
+ * the Glib version with this API
+ */
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
+#define TYPE_HV_BALLOON "hv-balloon"
+#define HV_BALLOON_GUID "525074DC-8985-46e2-8057-A307DC18A502"
+#define HV_BALLOON_PFN_SHIFT 12
+#define HV_BALLOON_PAGE_SIZE (1 << HV_BALLOON_PFN_SHIFT)
+
+/*
+ * 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_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
+ */
+
+typedef enum State {
+ /* not a real state */
+ S_NO_CHANGE = 0,
+
+ S_WAIT_RESET,
+ S_CLOSED,
+ S_VERSION,
+ S_CAPS,
+ S_POST_INIT_WAIT,
+ S_IDLE,
+ S_HOT_ADD_RB_WAIT,
+ S_HOT_ADD_POSTING,
+ S_HOT_ADD_REPLY_WAIT,
+ S_HOT_ADD_SKIP_CURRENT,
+ S_HOT_ADD_PROCESSED_CLEAR_PENDING,
+ S_HOT_ADD_PROCESSED_NEXT,
+ S_HOT_REMOVE,
+ S_BALLOON_POSTING,
+ S_BALLOON_RB_WAIT,
+ S_BALLOON_REPLY_WAIT,
+ S_UNBALLOON_POSTING,
+ S_UNBALLOON_RB_WAIT,
+ S_UNBALLOON_REPLY_WAIT,
+} State;
+
+typedef struct StateDesc {
+ State state;
+ const char *desc;
+} StateDesc;
+
+typedef struct PageRange {
+ uint64_t start;
+ uint64_t count;
+} PageRange;
+
+/* type safety */
+typedef struct PageRangeTree {
+ GTree *t;
+} PageRangeTree;
+
+typedef struct HAPVDIMMRange {
+ HAPVDIMMDevice *hapvdimm;
+
+ PageRange range;
+ uint64_t used;
+
+ /*
+ * Pages not currently usable due to guest alignment reqs or
+ * not hot added in the first place
+ */
+ uint64_t unused_head, unused_tail;
+
+ /* Memory removed from the guest backed by this HAPVDIMM */
+ PageRangeTree removed_guest, removed_both;
+} HAPVDIMMRange;
+
+/* type safety */
+typedef struct HAPVDIMMRangeTree {
+ GTree *t;
+} HAPVDIMMRangeTree;
+
+typedef struct HvBalloon {
+ VMBusDevice parent;
+ State state;
+ bool status_reports;
+
+ union dm_version version;
+ union dm_caps caps;
+
+ QEMUTimer post_init_timer;
+ guint del_todo_process_timer;
+
+ unsigned int trans_id;
+
+ /* Guest target size */
+ uint64_t target;
+ bool target_changed;
+ uint64_t target_diff;
+
+ /*
+ * All HAPVDIMMs under control of this driver
+ * (but excluding the ones in hapvdimms_del_todo)
+ */
+ HAPVDIMMRangeTree hapvdimms;
+
+ /* Non-HAPVDIMM removed memory */
+ PageRangeTree removed_guest, removed_both;
+
+ /* Grand totals of removed memory (both HAPVDIMM and non-HAPVDIMM) */
+ uint64_t removed_guest_ctr, removed_both_ctr;
+
+ /* HAPVDIMMs waiting to be added during current connection */
+ GSList *ha_todo;
+ uint64_t ha_current_count;
+
+ /* HAPVDIMMs waiting to be deleted, not in any of the above structures */
+ GSList *hapvdimms_del_todo;
+} HvBalloon;
+
+#define HV_BALLOON(obj) OBJECT_CHECK(HvBalloon, (obj), TYPE_HV_BALLOON)
+
+#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, \
+ }
+
+#define SUM_OVERFLOW_U64(in1, in2) ((in1) > UINT64_MAX - (in2))
+#define SUM_SATURATE_U64(in1, in2) \
+ ({ \
+ uint64_t _in1 = (in1), _in2 = (in2); \
+ uint64_t _result; \
+ \
+ if (!SUM_OVERFLOW_U64(_in1, _in2)) { \
+ _result = _in1 + _in2; \
+ } else { \
+ _result = UINT64_MAX; \
+ } \
+ \
+ _result; \
+ })
+
+typedef struct HvBalloonReq {
+ VMBusChanReq vmreq;
+} HvBalloonReq;
+
+/* PageRange */
+static void page_range_intersect(const PageRange *range,
+ uint64_t start, uint64_t count,
+ PageRange *out)
+{
+ uint64_t end1 = range->start + range->count;
+ uint64_t end2 = start + count;
+ uint64_t end = MIN(end1, end2);
+
+ out->start = MAX(range->start, start);
+ out->count = out->start < end ? end - out->start : 0;
+}
+
+static uint64_t page_range_intersection_size(const PageRange *range,
+ uint64_t start, uint64_t count)
+{
+ PageRange trange;
+
+ page_range_intersect(range, start, count, &trange);
+ return trange.count;
+}
+
+/* return just the part of range before (start) */
+static void page_range_part_before(const PageRange *range,
+ uint64_t start, PageRange *out)
+{
+ uint64_t endr = range->start + range->count;
+ uint64_t end = MIN(endr, start);
+
+ out->start = range->start;
+ if (end > out->start) {
+ out->count = end - out->start;
+ } else {
+ out->count = 0;
+ }
+}
+
+/* return just the part of range after (start, count) */
+static void page_range_part_after(const PageRange *range,
+ uint64_t start, uint64_t count,
+ PageRange *out)
+{
+ uint64_t end = range->start + range->count;
+ uint64_t ends = start + count;
+
+ out->start = MAX(range->start, ends);
+ if (end > out->start) {
+ out->count = end - out->start;
+ } else {
+ out->count = 0;
+ }
+}
+
+static bool page_range_joinable_left(const PageRange *range,
+ uint64_t start, uint64_t count)
+{
+ return start + count == range->start;
+}
+
+static bool page_range_joinable_right(const PageRange *range,
+ uint64_t start, uint64_t count)
+{
+ return range->start + range->count == start;
+}
+
+static bool page_range_joinable(const PageRange *range,
+ uint64_t start, uint64_t count)
+{
+ return page_range_joinable_left(range, start, count) ||
+ page_range_joinable_right(range, start, count);
+}
+
+/* PageRangeTree */
+static gint page_range_tree_key_compare(gconstpointer leftp,
+ gconstpointer rightp,
+ gpointer user_data)
+{
+ const uint64_t *left = leftp, *right = rightp;
+
+ if (*left < *right) {
+ return -1;
+ } else if (*left > *right) {
+ return 1;
+ } else { /* *left == *right */
+ return 0;
+ }
+}
+
+static GTreeNode *page_range_tree_insert_new(PageRangeTree tree,
+ uint64_t start, uint64_t count)
+{
+ uint64_t *key = g_malloc(sizeof(*key));
+ PageRange *range = g_malloc(sizeof(*range));
+
+ assert(count > 0);
+
+ *key = range->start = start;
+ range->count = count;
+
+ return g_tree_insert_node(tree.t, key, range);
+}
+
+static void page_range_tree_insert(PageRangeTree tree,
+ uint64_t start, uint64_t count,
+ uint64_t *dupcount)
+{
+ GTreeNode *node;
+ bool joinable;
+ uint64_t intersection;
+ PageRange *range;
+
+ assert(!SUM_OVERFLOW_U64(start, count));
+ if (count == 0) {
+ return;
+ }
+
+ node = g_tree_upper_bound(tree.t, &start);
+ if (node) {
+ node = g_tree_node_previous(node);
+ } else {
+ node = g_tree_node_last(tree.t);
+ }
+
+ if (node) {
+ range = g_tree_node_value(node);
+ assert(range);
+ intersection = page_range_intersection_size(range, start, count);
+ joinable = page_range_joinable_right(range, start, count);
+ }
+
+ if (!node ||
+ (!intersection && !joinable)) {
+ /*
+ * !node case: the tree is empty or the very first node in the tree
+ * already has a higher key (the start of its range).
+ * the other case: there is a gap in the tree between the new range
+ * and the previous one.
+ * anyway, let's just insert the new range into the tree.
+ */
+ node = page_range_tree_insert_new(tree, start, count);
+ assert(node);
+ range = g_tree_node_value(node);
+ assert(range);
+ } else {
+ /*
+ * the previous range in the tree either partially covers the new
+ * range or ends just at its beginning - extend it
+ */
+ if (dupcount) {
+ *dupcount += intersection;
+ }
+
+ count += start - range->start;
+ range->count = MAX(range->count, count);
+ }
+
+ /* check next nodes for possible merging */
+ for (node = g_tree_node_next(node); node; ) {
+ PageRange *rangecur;
+
+ rangecur = g_tree_node_value(node);
+ assert(rangecur);
+
+ intersection = page_range_intersection_size(rangecur,
+ range->start, range->count);
+ joinable = page_range_joinable_left(rangecur,
+ range->start, range->count);
+ if (!intersection && !joinable) {
+ /* the current node is disjoint */
+ break;
+ }
+
+ if (dupcount) {
+ *dupcount += intersection;
+ }
+
+ count = rangecur->count + (rangecur->start - range->start);
+ range->count = MAX(range->count, count);
+
+ /* the current node was merged in, remove it */
+ start = rangecur->start;
+ node = g_tree_node_next(node);
+ /* no hinted removal in GTree... */
+ g_tree_remove(tree.t, &start);
+ }
+}
+
+static bool page_range_tree_pop(PageRangeTree tree, PageRange *out,
+ uint64_t maxcount)
+{
+ GTreeNode *node;
+ PageRange *range;
+
+ node = g_tree_node_last(tree.t);
+ if (!node) {
+ return false;
+ }
+
+ range = g_tree_node_value(node);
+ assert(range);
+
+ out->start = range->start;
+
+ /* can't modify range->start as it is the node key */
+ if (range->count > maxcount) {
+ out->start += range->count - maxcount;
+ out->count = maxcount;
+ range->count -= maxcount;
+ } else {
+ out->count = range->count;
+ /* no hinted removal in GTree... */
+ g_tree_remove(tree.t, &out->start);
+ }
+
+ return true;
+}
+
+static bool page_range_tree_intree_any(PageRangeTree tree,
+ uint64_t start, uint64_t count)
+{
+ GTreeNode *node;
+
+ if (count == 0) {
+ return false;
+ }
+
+ /* find the first node that can possibly intersect our range */
+ node = g_tree_upper_bound(tree.t, &start);
+ if (node) {
+ /*
+ * a NULL node below means that the very first node in the tree
+ * already has a higher key (the start of its range).
+ */
+ node = g_tree_node_previous(node);
+ } else {
+ /* a NULL node below means that the tree is empty */
+ node = g_tree_node_last(tree.t);
+ }
+ /* node range start <= range start */
+
+ if (!node) {
+ /* node range start > range start */
+ node = g_tree_node_first(tree.t);
+ }
+
+ for ( ; node; node = g_tree_node_next(node)) {
+ PageRange *range = g_tree_node_value(node);
+
+ assert(range);
+ /*
+ * if this node starts beyond or at the end of our range so does
+ * every next one
+ */
+ if (range->start >= start + count) {
+ break;
+ }
+
+ if (page_range_intersection_size(range, start, count) > 0) {
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static PageRangeTree page_range_tree_new(void)
+{
+ PageRangeTree tree;
+
+ tree.t = g_tree_new_full(page_range_tree_key_compare, NULL,
+ g_free, g_free);
+ return tree;
+}
+
+static void page_range_tree_destroy(PageRangeTree *tree)
+{
+ /* g_tree_destroy() is not NULL-safe */
+ if (!tree->t) {
+ return;
+ }
+
+ g_tree_destroy(tree->t);
+ tree->t = NULL;
+}
+
+/* HAPVDIMMDevice */
+static uint64_t hapvdimm_get_addr(HAPVDIMMDevice *hapvdimm)
+{
+ return object_property_get_uint(OBJECT(hapvdimm), HAPVDIMM_ADDR_PROP,
+ &error_abort) / HV_BALLOON_PAGE_SIZE;
+}
+
+static uint64_t hapvdimm_get_size(HAPVDIMMDevice *hapvdimm)
+{
+ return object_property_get_uint(OBJECT(hapvdimm), HAPVDIMM_SIZE_PROP,
+ &error_abort) / HV_BALLOON_PAGE_SIZE;
+}
+
+static void hapvdimm_get_range(HAPVDIMMDevice *hapvdimm, PageRange *out)
+{
+ out->start = hapvdimm_get_addr(hapvdimm);
+ assert(out->start > 0);
+
+ out->count = hapvdimm_get_size(hapvdimm);
+ assert(out->count > 0);
+}
+
+static HostMemoryBackend *hapvdimm_get_memdev(HAPVDIMMDevice *hapvdimm)
+{
+ Object *memdev_obj;
+
+ memdev_obj = object_property_get_link(OBJECT(hapvdimm),
+ HAPVDIMM_MEMDEV_PROP,
+ &error_abort);
+ return MEMORY_BACKEND(memdev_obj);
+}
+
+/* HAPVDIMMRange */
+static HAPVDIMMRange *hapvdimm_range_new(HAPVDIMMDevice *hapvdimm)
+{
+ HAPVDIMMRange *hpr = g_malloc(sizeof(*hpr));
+
+ hpr->hapvdimm = HAPVDIMM(object_ref(hapvdimm));
+ hapvdimm_get_range(hapvdimm, &hpr->range);
+
+ hpr->removed_guest = page_range_tree_new();
+ hpr->removed_both = page_range_tree_new();
+
+ /* mark the whole range as unused */
+ hpr->used = 0;
+ hpr->unused_head = hpr->range.count;
+ hpr->unused_tail = 0;
+
+ return hpr;
+}
+
+static void hapvdimm_range_free(HAPVDIMMRange *hpr)
+{
+ g_autoptr(HAPVDIMMDevice) hapvdimm = g_steal_pointer(&hpr->hapvdimm);
+
+ page_range_tree_destroy(&hpr->removed_guest);
+ page_range_tree_destroy(&hpr->removed_both);
+
+ g_free(hpr);
+}
+
+/* the hapvdimm range reduced by unused head and tail */
+static void hapvdimm_range_get_effective_range(HAPVDIMMRange *hpr,
+ PageRange *out)
+{
+ out->start = hpr->range.start + hpr->unused_head;
+ out->count = hpr->range.count - hpr->unused_head - hpr->unused_tail;
+}
+
+/* HAPVDIMMRangeTree */
+static gint hapvdimm_tree_key_compare(gconstpointer leftp, gconstpointer rightp,
+ gpointer user_data)
+{
+ /*
+ * hapvdimm tree is also keyed on page range start, so we can simply reuse
+ * the comparison function from the page range tree
+ */
+ return page_range_tree_key_compare(leftp, rightp, user_data);
+}
+
+static HAPVDIMMRange *hapvdimm_tree_insert_new(HvBalloon *balloon,
+ HAPVDIMMDevice *hapvdimm)
+{
+ HAPVDIMMRange *hpr;
+ uint64_t *key;
+
+ hpr = hapvdimm_range_new(hapvdimm);
+
+ key = g_malloc(sizeof(*key));
+ *key = hpr->range.start;
+
+ g_tree_insert(balloon->hapvdimms.t, key, hpr);
+
+ return hpr;
+}
+
+/* The HAPVDIMM must not be on the ha_todo list since it's going to get unref'ed. */
+static void hapvdimm_tree_remove(HvBalloon *balloon, HAPVDIMMDevice *hapvdimm)
+{
+ uint64_t addr;
+
+ addr = hapvdimm_get_addr(hapvdimm);
+ assert(addr > 0);
+
+ g_tree_remove(balloon->hapvdimms.t, &addr);
+}
+
+/* total RAM includes memory currently removed from the guest */
+static gboolean hapvdimm_tree_total_ram_node(gpointer key,
+ gpointer value,
+ gpointer data)
+{
+ HAPVDIMMRange *hpr = value;
+ uint64_t *size = data;
+ PageRange rangeeff;
+
+ hapvdimm_range_get_effective_range(hpr, &rangeeff);
+ *size += rangeeff.count;
+
+ return false;
+}
+
+static uint64_t hapvdimm_tree_total_ram(HvBalloon *balloon)
+{
+ uint64_t size = 0;
+
+ g_tree_foreach(balloon->hapvdimms.t, hapvdimm_tree_total_ram_node, &size);
+ return size;
+}
+
+static void hapvdimm_tree_value_free(gpointer data)
+{
+ HAPVDIMMRange *hpr = data;
+
+ hapvdimm_range_free(hpr);
+}
+
+static HAPVDIMMRangeTree hapvdimm_tree_new(void)
+{
+ HAPVDIMMRangeTree tree;
+
+ tree.t = g_tree_new_full(hapvdimm_tree_key_compare, NULL, g_free,
+ hapvdimm_tree_value_free);
+ return tree;
+}
+
+static void hapvdimm_tree_destroy(HAPVDIMMRangeTree *tree)
+{
+ /* g_tree_destroy() is not NULL-safe */
+ if (!tree->t) {
+ return;
+ }
+
+ g_tree_destroy(tree->t);
+ tree->t = NULL;
+}
+
+static gboolean ha_todo_add_all_node(gpointer key,
+ gpointer value,
+ gpointer data)
+{
+ HAPVDIMMRange *hpr = value;
+ HvBalloon *balloon = data;
+
+ /* assume the hpr is fresh */
+ assert(hpr->used == 0);
+ assert(hpr->unused_head == hpr->range.count);
+ assert(hpr->unused_tail == 0);
+
+ balloon->ha_todo = g_slist_append(balloon->ha_todo, hpr);
+
+ return false;
+}
+
+static void ha_todo_add_all(HvBalloon *balloon)
+{
+ assert(balloon->ha_todo == NULL);
+ g_tree_foreach(balloon->hapvdimms.t, ha_todo_add_all_node, balloon);
+}
+
+static void ha_todo_clear(HvBalloon *balloon)
+{
+ g_slist_free(g_steal_pointer(&balloon->ha_todo));
+}
+
+/* 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 hapvdimm_size_pages = hapvdimm_tree_total_ram(balloon);
+
+ assert(ram_size_pages > 0);
+
+ return SUM_SATURATE_U64(ram_size_pages, hapvdimm_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;
+}
+
+static bool hv_balloon_state_is_init(HvBalloon *balloon)
+{
+ return balloon->state == S_WAIT_RESET ||
+ balloon->state == S_CLOSED ||
+ balloon->state == S_VERSION ||
+ balloon->state == S_CAPS;
+}
+
+/* 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 void del_todo_process(HvBalloon *balloon)
+{
+ while (balloon->hapvdimms_del_todo) {
+ HAPVDIMMDevice *hapvdimm = balloon->hapvdimms_del_todo->data;
+ HostMemoryBackend *backend;
+ const char *backend_id;
+
+ backend = hapvdimm_get_memdev(hapvdimm);
+ backend_id = object_get_canonical_path_component(OBJECT(backend));
+
+ object_unparent(OBJECT(hapvdimm));
+ object_unref(OBJECT(hapvdimm));
+ qapi_event_send_hv_balloon_memory_backend_unused(backend_id);
+
+ balloon->hapvdimms_del_todo =
+ g_slist_remove(balloon->hapvdimms_del_todo, hapvdimm);
+ }
+
+ if (balloon->del_todo_process_timer) {
+ g_source_remove(balloon->del_todo_process_timer);
+ balloon->del_todo_process_timer = 0;
+ }
+}
+
+static gboolean del_todo_process_timer(gpointer user_data)
+{
+ HvBalloon *balloon = user_data;
+
+ balloon->del_todo_process_timer = 0;
+
+ del_todo_process(balloon);
+
+ return G_SOURCE_REMOVE;
+}
+
+static void del_todo_append(HvBalloon *balloon,
+ HAPVDIMMDevice *hapvdimm)
+{
+ balloon->hapvdimms_del_todo = g_slist_append(balloon->hapvdimms_del_todo,
+ object_ref(hapvdimm));
+}
+
+static void del_todo_add(HvBalloon *balloon,
+ HAPVDIMMDevice *hapvdimm)
+{
+ hapvdimm_tree_remove(balloon, hapvdimm);
+ del_todo_append(balloon, hapvdimm);
+}
+
+static gboolean del_todo_add_all_node(gpointer key,
+ gpointer value,
+ gpointer data)
+{
+ HAPVDIMMRange *hpr = value;
+ HvBalloon *balloon = data;
+
+ del_todo_append(balloon, hpr->hapvdimm);
+
+ return false;
+}
+
+static void del_todo_add_all(HvBalloon *balloon)
+{
+ g_tree_foreach(balloon->hapvdimms.t, del_todo_add_all_node, balloon);
+ hapvdimm_tree_destroy(&balloon->hapvdimms);
+
+ balloon->hapvdimms = hapvdimm_tree_new();
+}
+
+static void del_todo_add_all_from_ha_todo(HvBalloon *balloon)
+{
+ while (balloon->ha_todo) {
+ HAPVDIMMRange *hpr = balloon->ha_todo->data;
+
+ del_todo_add(balloon, hpr->hapvdimm);
+ balloon->ha_todo = g_slist_remove(balloon->ha_todo, hpr);
+ }
+}
+
+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,
+ HAPVDIMMRange **hpr)
+{
+ /* Try the boot memory first */
+ if (g_tree_nnodes(balloon->removed_guest.t) > 0) {
+ *dtree = balloon->removed_guest;
+ *dctr = &balloon->removed_guest_ctr;
+ *hpr = NULL;
+ } else if (g_tree_nnodes(balloon->removed_both.t) > 0) {
+ *dtree = balloon->removed_both;
+ *dctr = &balloon->removed_both_ctr;
+ *hpr = NULL;
+ } else {
+ GTreeNode *node;
+
+ for (node = g_tree_node_first(balloon->hapvdimms.t); node;
+ node = g_tree_node_next(node)) {
+ HAPVDIMMRange *hprnode = g_tree_node_value(node);
+
+ assert(hprnode);
+ if (g_tree_nnodes(hprnode->removed_guest.t) > 0) {
+ *dtree = hprnode->removed_guest;
+ *dctr = &balloon->removed_guest_ctr;
+ *hpr = hprnode;
+ break;
+ } else if (g_tree_nnodes(hprnode->removed_both.t) > 0) {
+ *dtree = hprnode->removed_both;
+ *dctr = &balloon->removed_both_ctr;
+ *hpr = hprnode;
+ break;
+ }
+ }
+
+ if (!node) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static void hv_balloon_balloon_unballoon_start(HvBalloon *balloon,
+ uint64_t ram_size_pages,
+ StateDesc *stdesc)
+{
+ uint64_t total_removed = hv_balloon_total_removed_rs(balloon,
+ ram_size_pages);
+
+ assert(balloon->state == S_IDLE);
+ assert(ram_size_pages > 0);
+
+ /*
+ * we need to cache the value when starting the (un)balloon procedure
+ * in case somebody changes the balloon target when the procedure is
+ * in progress
+ */
+ if (balloon->target < ram_size_pages - total_removed) {
+ balloon->target_diff = ram_size_pages - total_removed - balloon->target;
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_BALLOON_RB_WAIT);
+ } else {
+ balloon->target_diff = balloon->target -
+ (ram_size_pages - total_removed);
+
+ /*
+ * careful here, the user might have set the balloon target
+ * above the RAM size, so above the total removed count
+ */
+ balloon->target_diff = MIN(balloon->target_diff, total_removed);
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_UNBALLOON_RB_WAIT);
+ }
+
+ balloon->target_changed = false;
+}
+
+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;
+ HAPVDIMMRange *hpr;
+ 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->target_diff > 0);
+
+ if (!hv_balloon_unballoon_get_source(balloon, &dtree, &dctr, &hpr)) {
+ error_report("trying to unballoon but nothing ballooned");
+ /*
+ * there is little we can do as we might have already
+ * sent the guest a partial request we can't cancel
+ */
+ return;
+ }
+
+ 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 = page_range_tree_pop(dtree, &range, MIN(balloon->target_diff,
+ HV_BALLOON_HA_CHUNK_PAGES));
+ assert(bret);
+ /* TODO: madvise? */
+
+ *dctr -= range.count;
+ balloon->target_diff -= range.count;
+ if (hpr) {
+ hpr->used += 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->target_diff > 0;
+
+ trace_hv_balloon_outgoing_unballoon(ur->hdr.trans_id,
+ range.count, range.start,
+ balloon->target_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 void hv_balloon_hot_add_start(HvBalloon *balloon, StateDesc *stdesc)
+{
+ HAPVDIMMRange *hpr;
+ PageRange range;
+
+ assert(balloon->state == S_IDLE);
+ assert(balloon->ha_todo);
+
+ hpr = balloon->ha_todo->data;
+
+ range.start = QEMU_ALIGN_UP(hpr->range.start,
+ (1 << balloon->caps.cap_bits.hot_add_alignment)
+ * (MiB / HV_BALLOON_PAGE_SIZE));
+ hpr->unused_head = range.start - hpr->range.start;
+ if (hpr->unused_head >= hpr->range.count) {
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_SKIP_CURRENT);
+ return;
+ }
+
+ range.count = hpr->range.count - hpr->unused_head;
+ range.count = QEMU_ALIGN_DOWN(range.count,
+ (1 << balloon->caps.cap_bits.hot_add_alignment)
+ * (MiB / HV_BALLOON_PAGE_SIZE));
+ if (range.count == 0) {
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_SKIP_CURRENT);
+ return;
+ }
+ hpr->unused_tail = hpr->range.count - hpr->unused_head - range.count;
+ hpr->used = 0;
+
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_RB_WAIT);
+}
+
+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)
+{
+ VMBusChannel *chan = hv_balloon_get_channel(balloon);
+ HAPVDIMMRange *hpr;
+ struct dm_hot_add *ha;
+ size_t ha_size = sizeof(*ha) + sizeof(ha->range);
+ union dm_mem_page_range *ha_region;
+ PageRange range;
+ uint64_t chunk_max_size;
+ ssize_t ret;
+
+ assert(balloon->state == S_HOT_ADD_POSTING);
+ assert(balloon->ha_todo);
+
+ hpr = balloon->ha_todo->data;
+
+ range.start = hpr->range.start + hpr->unused_head + hpr->used;
+ range.count = hpr->range.count;
+ range.count -= hpr->unused_head;
+ range.count -= hpr->used;
+ range.count -= hpr->unused_tail;
+
+ chunk_max_size = MAX((1 << balloon->caps.cap_bits.hot_add_alignment) *
+ (MiB / HV_BALLOON_PAGE_SIZE),
+ HV_BALLOON_HA_CHUNK_PAGES);
+ range.count = MIN(range.count, chunk_max_size);
+ balloon->ha_current_count = range.count;
+
+ 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 = range.start;
+ ha->range.finfo.page_cnt = range.count;
+ ha_region->finfo.start_page = range.start;
+ ha_region->finfo.page_cnt = ha->range.finfo.page_cnt;
+
+ trace_hv_balloon_outgoing_hot_add(ha->hdr.trans_id,
+ range.count, 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_hot_add_finish(HvBalloon *balloon, StateDesc *stdesc)
+{
+ HAPVDIMMRange *hpr;
+
+ assert(balloon->state == S_HOT_ADD_SKIP_CURRENT ||
+ balloon->state == S_HOT_ADD_PROCESSED_CLEAR_PENDING ||
+ balloon->state == S_HOT_ADD_PROCESSED_NEXT);
+ assert(balloon->ha_todo);
+
+ hpr = balloon->ha_todo->data;
+
+ balloon->ha_todo = g_slist_remove(balloon->ha_todo, hpr);
+ if (balloon->state == S_HOT_ADD_SKIP_CURRENT) {
+ del_todo_add(balloon, hpr->hapvdimm);
+ } else if (balloon->state == S_HOT_ADD_PROCESSED_CLEAR_PENDING) {
+ del_todo_add_all_from_ha_todo(balloon);
+ }
+
+ /* let other things happen, too, between hot adds to be done */
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_IDLE);
+}
+
+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->target_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->target_diff, HV_BALLOON_HR_CHUNK_PAGES);
+
+ trace_hv_balloon_outgoing_balloon(bl.hdr.trans_id, bl.num_pages,
+ balloon->target_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(HvBalloon *balloon,
+ StateDesc *stdesc)
+{
+ bool can_balloon = balloon->caps.cap_bits.balloon;
+ bool want_unballoon = false;
+ bool want_hot_add = balloon->ha_todo != NULL;
+ bool want_balloon = false;
+ uint64_t ram_size_pages;
+
+ assert(balloon->state == S_IDLE);
+
+ if (can_balloon && balloon->target_changed) {
+ uint64_t total_removed;
+
+ ram_size_pages = hv_balloon_total_ram(balloon);
+ total_removed = hv_balloon_total_removed_rs(balloon,
+ ram_size_pages);
+
+ want_unballoon = total_removed > 0 &&
+ balloon->target > ram_size_pages - total_removed;
+ want_balloon = balloon->target < ram_size_pages - total_removed;
+ }
+
+ /*
+ * the order here is important, first we unballoon, then hot add,
+ * then balloon (or hot remove)
+ */
+ if (want_unballoon) {
+ hv_balloon_balloon_unballoon_start(balloon, ram_size_pages, stdesc);
+ } else if (want_hot_add) {
+ hv_balloon_hot_add_start(balloon, stdesc);
+ } else if (want_balloon) {
+ hv_balloon_balloon_unballoon_start(balloon, ram_size_pages, stdesc);
+ }
+}
+
+static const struct {
+ void (*handler)(HvBalloon *balloon, StateDesc *stdesc);
+} state_handlers[] = {
+ [S_IDLE].handler = hv_balloon_idle_state,
+ [S_UNBALLOON_RB_WAIT].handler = hv_balloon_unballoon_rb_wait,
+ [S_UNBALLOON_POSTING].handler = hv_balloon_unballoon_posting,
+ [S_HOT_ADD_RB_WAIT].handler = hv_balloon_hot_add_rb_wait,
+ [S_HOT_ADD_POSTING].handler = hv_balloon_hot_add_posting,
+ [S_HOT_ADD_SKIP_CURRENT].handler = hv_balloon_hot_add_finish,
+ [S_HOT_ADD_PROCESSED_CLEAR_PENDING].handler = hv_balloon_hot_add_finish,
+ [S_HOT_ADD_PROCESSED_NEXT].handler = hv_balloon_hot_add_finish,
+ [S_BALLOON_RB_WAIT].handler = hv_balloon_balloon_rb_wait,
+ [S_BALLOON_POSTING].handler = hv_balloon_balloon_posting,
+};
+
+static void hv_balloon_handle_state(HvBalloon *balloon, StateDesc *stdesc)
+{
+ if (!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;
+ 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)
+{
+ GTreeNode *node;
+ PageRangeTree globaltree = both ? balloon->removed_both :
+ balloon->removed_guest;
+ uint64_t *globalctr = both ? &balloon->removed_both_ctr :
+ &balloon->removed_guest_ctr;
+
+ if (range->count == 0) {
+ return;
+ }
+
+ trace_hv_balloon_remove_response(range->count, range->start, both);
+
+ /* find the first node that can possibly intersect our range */
+ node = g_tree_upper_bound(balloon->hapvdimms.t, &range->start);
+ if (node) {
+ /*
+ * a NULL node below means that the very first node in the tree
+ * already has a higher key (the start of its range).
+ */
+ node = g_tree_node_previous(node);
+ } else {
+ /* a NULL node below means that the tree is empty */
+ node = g_tree_node_last(balloon->hapvdimms.t);
+ }
+ /* node range start <= range start */
+
+ if (!node) {
+ /* node range start > range start */
+ node = g_tree_node_first(balloon->hapvdimms.t);
+ }
+
+ for ( ; node && range->count > 0; node = g_tree_node_next(node)) {
+ HAPVDIMMRange *hpr = g_tree_node_value(node);
+ PageRangeTree hprtree;
+ PageRange rangeeff, rangehole, rangecommon;
+ uint64_t hprremoved = 0;
+
+ assert(hpr);
+ hprtree = both ? hpr->removed_both : hpr->removed_guest;
+ hapvdimm_range_get_effective_range(hpr, &rangeeff);
+
+ /*
+ * if this node starts beyond or at the end of the range so does
+ * every next one
+ */
+ if (rangeeff.start >= range->start + range->count) {
+ break;
+ }
+
+ /* process the hole before the current hpr, 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 the hpr part, can be empty for the very first node processed
+ * or due to difference between the nominal and effective hpr start
+ */
+ page_range_intersect(range, rangeeff.start, rangeeff.count,
+ &rangecommon);
+ hv_balloon_remove_response_insert_range(hprtree, &rangecommon,
+ globalctr, removedctr,
+ &hprremoved);
+ hpr->used -= hprremoved;
+ if (rangecommon.count > 0) {
+ trace_hv_balloon_remove_response_common(rangecommon.count,
+ rangecommon.start,
+ range->count, range->start,
+ rangeeff.count,
+ rangeeff.start, hprremoved,
+ both);
+ }
+
+ /* calculate what's left after the current hpr */
+ rangecommon = *range;
+ page_range_part_after(&rangecommon, rangeeff.start, rangeeff.count,
+ range);
+ }
+
+ /* process the remainder of the range that lies outside of the hpr tree */
+ 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; ) {
+ void *addr = (void *)((range->start + pageoff) * HV_BALLOON_PAGE_SIZE);
+ RAMBlock *rb;
+ ram_addr_t rb_offset;
+ size_t rb_page_size;
+ size_t discard_size;
+
+ 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;
+ 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;
+
+ removed_host_addr = page_range_tree_new();
+ 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 = 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);
+ page_range_tree_destroy(&removed_host_addr);
+
+ if (removedcnt > balloon->target_diff) {
+ warn_report("guest reported more pages removed than currently pending (%"PRIu64" vs %"PRIu64")",
+ removedcnt, balloon->target_diff);
+ balloon->target_diff = 0;
+ } else {
+ balloon->target_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_reports;
+ hv_balloon_send_packet(vmreq->chan, (struct dm_message *)&respCap);
+
+ if (balloon->caps.cap_bits.hot_add) {
+ ha_todo_add_all(balloon);
+ }
+
+ 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_reports) {
+ return;
+ }
+
+ qapi_event_send_hv_balloon_status_report((uint64_t)msgStatus->num_committed *
+ HV_BALLOON_PAGE_SIZE,
+ (uint64_t)msgStatus->num_avail *
+ HV_BALLOON_PAGE_SIZE);
+}
+
+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++;
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_IDLE);
+}
+
+static void hv_balloon_handle_hot_add_response(HvBalloon *balloon,
+ HvBalloonReq *req,
+ StateDesc *stdesc)
+{
+ VMBusChanReq *vmreq = &req->vmreq;
+ struct dm_hot_add_response *msgHaR = vmreq->msg;
+ HAPVDIMMRange *hpr;
+
+ if (balloon->state != S_HOT_ADD_REPLY_WAIT) {
+ warn_report("unexpected DM_HOT_ADD_RESPONSE in %d state",
+ balloon->state);
+ return;
+ }
+
+ 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++;
+
+ assert(balloon->ha_todo);
+ hpr = balloon->ha_todo->data;
+
+ 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;
+ }
+
+ hpr->used += msgHaR->page_count;
+ }
+
+ if (!msgHaR->result || msgHaR->page_count < balloon->ha_current_count) {
+ if (hpr->used == 0) {
+ /*
+ * apparently the guest didn't like the current range at all,
+ * let's try the next one
+ */
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_SKIP_CURRENT);
+ return;
+ }
+
+ /*
+ * the current planned range was only partially hot-added, take note
+ * how much of it remains and don't attempt any further hot adds
+ */
+ hpr->unused_tail = hpr->range.count - hpr->unused_head - hpr->used;
+
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_PROCESSED_CLEAR_PENDING);
+ return;
+ }
+
+ /* any pages remaining in this hpr? */
+ if (hpr->range.count - hpr->unused_head - hpr->used -
+ hpr->unused_tail > 0) {
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_RB_WAIT);
+ } else {
+ HV_BALLOON_STATE_DESC_SET(stdesc, S_HOT_ADD_PROCESSED_NEXT);
+ }
+}
+
+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 */
+ msgBR->more_pages = 0;
+ balloon->target_diff = 0;
+ } else {
+ hv_balloon_handle_remove_ranges(balloon,
+ msgBR->range_array,
+ msgBR->range_count);
+ }
+
+ if (!msgBR->more_pages) {
+ balloon->trans_id++;
+
+ if (balloon->target_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_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;
+}
+
+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);
+}
+
+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);
+}
+
+void qmp_hv_balloon_add_memory(const char *id, Error **errp)
+{
+ HvBalloon *balloon;
+ uint64_t align;
+ g_autofree gchar *align_str = NULL;
+ g_autoptr(QDict) qdict = NULL;
+ g_autoptr(DeviceState) dev = NULL;
+ HAPVDIMMDevice *hapvdimm;
+ PageRange range;
+ HAPVDIMMRange *hpr;
+
+ balloon = HV_BALLOON(object_resolve_path_type("", TYPE_HV_BALLOON, NULL));
+ if (!balloon) {
+ error_setg(errp, "no %s device present", TYPE_HV_BALLOON);
+ return;
+ }
+
+ if (hv_balloon_state_is_init(balloon)) {
+ error_setg(errp, "no guest attached to the DM protocol yet");
+ return;
+ }
+
+ if (!balloon->caps.cap_bits.hot_add) {
+ error_setg(errp,
+ "the current DM protocol guest has no support for memory hot add");
+ return;
+ }
+
+ /* add device */
+ qdict = qdict_new();
+ qdict_put_str(qdict, "driver", TYPE_HAPVDIMM);
+ qdict_put_str(qdict, HAPVDIMM_MEMDEV_PROP, id);
+
+ align = (1 << balloon->caps.cap_bits.hot_add_alignment) * MiB;
+ align_str = g_strdup_printf("%" PRIu64, align);
+ qdict_put_str(qdict, HAPVDIMM_ALIGN_PROP, align_str);
+
+ hapvdimm_allow_adding();
+ dev = qdev_device_add_from_qdict(qdict, false, errp);
+ hapvdimm_disallow_adding();
+ if (!dev) {
+ return;
+ }
+
+ hapvdimm = HAPVDIMM(dev);
+
+ hapvdimm_get_range(hapvdimm, &range);
+ if (page_range_tree_intree_any(balloon->removed_guest,
+ range.start, range.count) ||
+ page_range_tree_intree_any(balloon->removed_both,
+ range.start, range.count)) {
+ error_setg(errp,
+ "some of the device new pages were already returned by the guest. this should not happen, please reboot the guest and try again");
+ return;
+ }
+
+ trace_hv_balloon_hapvdimm_range_add(range.count, range.start);
+
+ hpr = hapvdimm_tree_insert_new(balloon, hapvdimm);
+
+ balloon->ha_todo = g_slist_append(balloon->ha_todo, hpr);
+
+ hv_balloon_event_loop(balloon);
+}
+
+static void hv_balloon_notify_cb(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_open_channel(VMBusChannel *chan)
+{
+ HvBalloon *balloon = HV_BALLOON(vmbus_channel_device(chan));
+
+ if (balloon->state != S_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_close_channel(VMBusChannel *chan)
+{
+ HvBalloon *balloon = HV_BALLOON(vmbus_channel_device(chan));
+
+ timer_del(&balloon->post_init_timer);
+
+ 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(void *opaque)
+{
+ HvBalloon *balloon = HV_BALLOON(opaque);
+
+ if (!balloon->hapvdimms_del_todo) {
+ return;
+ }
+
+ if (balloon->del_todo_process_timer) {
+ return;
+ }
+
+ balloon->del_todo_process_timer = g_idle_add(del_todo_process_timer,
+ balloon);
+}
+
+static void hv_balloon_dev_realize(VMBusDevice *vdev, Error **errp)
+{
+ ERRP_GUARD();
+ HvBalloon *balloon = HV_BALLOON(vdev);
+ int ret;
+
+ /* used by hv_balloon_stat() */
+ balloon->hapvdimms = hapvdimm_tree_new();
+ 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");
+ goto ret_tree;
+ }
+
+ 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;
+
+ret_tree:
+ hapvdimm_tree_destroy(&balloon->hapvdimms);
+}
+
+static void hv_balloon_reset_destroy_common(HvBalloon *balloon)
+{
+ ha_todo_clear(balloon);
+ del_todo_add_all(balloon);
+}
+
+static void hv_balloon_dev_reset(VMBusDevice *vdev)
+{
+ HvBalloon *balloon = HV_BALLOON(vdev);
+
+ page_range_tree_destroy(&balloon->removed_guest);
+ page_range_tree_destroy(&balloon->removed_both);
+ balloon->removed_guest = page_range_tree_new();
+ balloon->removed_both = page_range_tree_new();
+
+ hv_balloon_reset_destroy_common(balloon);
+
+ balloon->trans_id = 0;
+ balloon->removed_guest_ctr = 0;
+ balloon->removed_both_ctr = 0;
+
+ HV_BALLOON_SET_STATE(balloon, S_CLOSED);
+ hv_balloon_event_loop(balloon);
+}
+
+static void hv_balloon_dev_unrealize(VMBusDevice *vdev)
+{
+ HvBalloon *balloon = HV_BALLOON(vdev);
+
+ qemu_unregister_reset(hv_balloon_system_reset, balloon);
+
+ hv_balloon_reset_destroy_common(balloon);
+
+ del_todo_process(balloon);
+ assert(!balloon->del_todo_process_timer);
+
+ qemu_remove_balloon_handler(balloon);
+
+ page_range_tree_destroy(&balloon->removed_guest);
+ page_range_tree_destroy(&balloon->removed_both);
+ hapvdimm_tree_destroy(&balloon->hapvdimms);
+}
+
+static Property hv_balloon_properties[] = {
+ DEFINE_PROP_BOOL("status-report", HvBalloon,
+ status_reports, false),
+ 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);
+
+ 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_dev_realize;
+ vdc->vmdev_unrealize = hv_balloon_dev_unrealize;
+ vdc->vmdev_reset = hv_balloon_dev_reset;
+ vdc->open_channel = hv_balloon_open_channel;
+ vdc->close_channel = hv_balloon_close_channel;
+ vdc->chan_notify_cb = hv_balloon_notify_cb;
+}
+
+static const TypeInfo hv_balloon_type_info = {
+ .name = TYPE_HV_BALLOON,
+ .parent = TYPE_VMBUS_DEVICE,
+ .instance_size = sizeof(HvBalloon),
+ .class_init = hv_balloon_class_init,
+};
+
+static void hv_balloon_register_types(void)
+{
+ type_register_static(&hv_balloon_type_info);
+}
+
+type_init(hv_balloon_register_types)
@@ -2,3 +2,4 @@ specific_ss.add(when: 'CONFIG_HYPERV', if_true: files('hyperv.c'))
specific_ss.add(when: 'CONFIG_HYPERV_TESTDEV', if_true: files('hyperv_testdev.c'))
specific_ss.add(when: 'CONFIG_VMBUS', if_true: files('vmbus.c'))
specific_ss.add(when: 'CONFIG_SYNDBG', if_true: files('syndbg.c'))
+specific_ss.add(when: 'CONFIG_HV_BALLOON', if_true: files('hv-balloon.c'))
@@ -16,3 +16,19 @@ vmbus_gpadl_torndown(uint32_t gpadl_id) "gpadl #%d"
vmbus_open_channel(uint32_t chan_id, uint32_t gpadl_id, uint32_t target_vp) "channel #%d gpadl #%d target vp %d"
vmbus_channel_open(uint32_t chan_id, uint32_t status) "channel #%d status %d"
vmbus_close_channel(uint32_t chan_id) "channel #%d"
+
+# hv-balloon
+hv_balloon_state_change(const char *tostr) "-> %s"
+hv_balloon_incoming_version(uint16_t major, uint16_t minor) "incoming proto version %u.%u"
+hv_balloon_incoming_caps(uint32_t caps) "incoming caps 0x%x"
+hv_balloon_outgoing_unballoon(uint32_t trans_id, uint64_t count, uint64_t start, uint64_t rempages) "posting unballoon %"PRIu32" for %"PRIu64" @ 0x%"PRIx64", remaining %"PRIu64
+hv_balloon_incoming_unballoon(uint32_t trans_id) "incoming unballoon response %"PRIu32
+hv_balloon_outgoing_hot_add(uint32_t trans_id, uint64_t count, uint64_t start) "posting hot add %"PRIu32" for %"PRIu64" @ 0x%"PRIx64
+hv_balloon_incoming_hot_add(uint32_t trans_id, uint32_t result, uint32_t count) "incoming hot add response %"PRIu32", result %"PRIu32", count %"PRIu32
+hv_balloon_outgoing_balloon(uint32_t trans_id, uint64_t count, uint64_t rempages) "posting balloon %"PRIu32" for %"PRIu64", remaining %"PRIu64
+hv_balloon_incoming_balloon(uint32_t trans_id, uint32_t range_count, uint32_t more_pages) "incoming balloon response %"PRIu32", ranges %"PRIu32", more %"PRIu32
+hv_balloon_hapvdimm_range_add(uint64_t count, uint64_t start) "adding hapvdimm range %"PRIu64" @ 0x%"PRIx64
+hv_balloon_remove_response(uint64_t count, uint64_t start, unsigned int both) "processing remove response range %"PRIu64" @ 0x%"PRIx64", both %u"
+hv_balloon_remove_response_hole(uint64_t counthole, uint64_t starthole, uint64_t countrange, uint64_t startrange, uint64_t starthpr, unsigned int both) "response range hole %"PRIu64" @ 0x%"PRIx64" from range %"PRIu64" @ 0x%"PRIx64", before hpr start 0x%"PRIx64", both %u"
+hv_balloon_remove_response_common(uint64_t countcommon, uint64_t startcommon, uint64_t countrange, uint64_t startrange, uint64_t counthpr, uint64_t starthpr, uint64_t removed, unsigned int both) "response common range %"PRIu64" @ 0x%"PRIx64" from range %"PRIu64" @ 0x%"PRIx64" with hpr %"PRIu64" @ 0x%"PRIx64", removed %"PRIu64", both %u"
+hv_balloon_remove_response_remainder(uint64_t count, uint64_t start, unsigned int both) "remove response remaining range %"PRIu64" @ 0x%"PRIx64", both %u"
@@ -2504,7 +2504,8 @@ host_kconfig = \
('CONFIG_LINUX' in config_host ? ['CONFIG_LINUX=y'] : []) + \
(have_pvrdma ? ['CONFIG_PVRDMA=y'] : []) + \
(multiprocess_allowed ? ['CONFIG_MULTIPROCESS_ALLOWED=y'] : []) + \
- (vfio_user_server_allowed ? ['CONFIG_VFIO_USER_SERVER_ALLOWED=y'] : [])
+ (vfio_user_server_allowed ? ['CONFIG_VFIO_USER_SERVER_ALLOWED=y'] : []) + \
+ ('CONFIG_HV_BALLOON_POSSIBLE' in config_host ? ['CONFIG_HV_BALLOON_POSSIBLE=y'] : [])
ignored = [ 'TARGET_XML_FILES', 'TARGET_ABI_DIR', 'TARGET_ARCH' ]
@@ -3975,6 +3976,7 @@ summary_info += {'libudev': libudev}
# Dummy dependency, keep .found()
summary_info += {'FUSE lseek': fuse_lseek.found()}
summary_info += {'selinux': selinux}
+summary_info += {'hv-balloon support': config_host.has_key('CONFIG_HV_BALLOON_POSSIBLE')}
summary(summary_info, bool_yn: true, section: 'Dependencies')
if not supported_cpus.contains(cpu)
@@ -1104,6 +1104,74 @@
{ 'event': 'BALLOON_CHANGE',
'data': { 'actual': 'int' } }
+##
+# @hv-balloon-add-memory:
+#
+# Hot-add memory backend via Hyper-V Dynamic Memory Protocol.
+#
+# @id: the name of the memory backend object to hot-add
+#
+# Returns: Nothing on success
+# Error if there's no guest connected with hot-add capability,
+# @id is not a valid memory backend or it's already in use.
+#
+# Since: TBD
+#
+# Example:
+#
+# -> { "execute": "hv-balloon-add-memory", "arguments": { "id": "mb1" } }
+# <- { "return": {} }
+#
+##
+{ 'command': 'hv-balloon-add-memory', 'data': {'id': 'str'} }
+
+##
+# @HV_BALLOON_STATUS_REPORT:
+#
+# Emitted when the hv-balloon driver receives a "STATUS" message from
+# the guest.
+#
+# @commited: the amount of memory in use inside the guest plus the amount
+# of the memory unusable inside the guest (ballooned out,
+# offline, etc.)
+#
+# @available: the amount of the memory inside the guest available for new
+# allocations ("free")
+#
+# Since: TBD
+#
+# Example:
+#
+# <- { "event": "HV_BALLOON_STATUS_REPORT",
+# "data": { "commited": 816640000, "available": 3333054464 },
+# "timestamp": { "seconds": 1600295492, "microseconds": 661044 } }
+#
+##
+{ 'event': 'HV_BALLOON_STATUS_REPORT',
+ 'data': { 'commited': 'size', 'available': 'size' } }
+
+##
+# @HV_BALLOON_MEMORY_BACKEND_UNUSED:
+#
+# Emitted when the hv-balloon driver marks a memory backend object
+# unused so it can now be removed, if required.
+#
+# This can happen because the VM was restarted.
+#
+# @id: the memory backend object id
+#
+# Since: TBD
+#
+# Example:
+#
+# <- { "event": "HV_BALLOON_MEMORY_BACKEND_UNUSED",
+# "data": { "id": "mb1" },
+# "timestamp": { "seconds": 1600295492, "microseconds": 661044 } }
+#
+##
+{ 'event': 'HV_BALLOON_MEMORY_BACKEND_UNUSED',
+ 'data': { 'id': 'str' } }
+
##
# @MemoryInfo:
#