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1 | bd322087 | aliguori | /*
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2 | bd322087 | aliguori | * Virtio Block Device
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3 | bd322087 | aliguori | *
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4 | bd322087 | aliguori | * Copyright IBM, Corp. 2008
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5 | bd322087 | aliguori | *
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6 | bd322087 | aliguori | * Authors:
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7 | bd322087 | aliguori | * Anthony Liguori <aliguori@us.ibm.com>
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8 | bd322087 | aliguori | *
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9 | bd322087 | aliguori | * This work is licensed under the terms of the GNU GPL, version 2. See
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10 | bd322087 | aliguori | * the COPYING file in the top-level directory.
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11 | bd322087 | aliguori | *
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12 | bd322087 | aliguori | */
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13 | bd322087 | aliguori | |
14 | fa6111f2 | Amit Shah | #include "iov.h" |
15 | bd322087 | aliguori | #include "qemu-common.h" |
16 | bd322087 | aliguori | #include "virtio.h" |
17 | bd322087 | aliguori | #include "pc.h" |
18 | bd322087 | aliguori | #include "cpu.h" |
19 | 625a5bef | Adam Litke | #include "monitor.h" |
20 | bd322087 | aliguori | #include "balloon.h" |
21 | bd322087 | aliguori | #include "virtio-balloon.h" |
22 | bd322087 | aliguori | #include "kvm.h" |
23 | 625a5bef | Adam Litke | #include "qlist.h" |
24 | 625a5bef | Adam Litke | #include "qint.h" |
25 | 625a5bef | Adam Litke | #include "qstring.h" |
26 | bd322087 | aliguori | |
27 | bd322087 | aliguori | #if defined(__linux__)
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28 | bd322087 | aliguori | #include <sys/mman.h> |
29 | bd322087 | aliguori | #endif
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30 | bd322087 | aliguori | |
31 | 07b0403d | Eduardo Habkost | /* Disable guest-provided stats by now (https://bugzilla.redhat.com/show_bug.cgi?id=623903) */
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32 | 07b0403d | Eduardo Habkost | #define ENABLE_GUEST_STATS 0 |
33 | 07b0403d | Eduardo Habkost | |
34 | 07b0403d | Eduardo Habkost | |
35 | bd322087 | aliguori | typedef struct VirtIOBalloon |
36 | bd322087 | aliguori | { |
37 | bd322087 | aliguori | VirtIODevice vdev; |
38 | 625a5bef | Adam Litke | VirtQueue *ivq, *dvq, *svq; |
39 | bd322087 | aliguori | uint32_t num_pages; |
40 | bd322087 | aliguori | uint32_t actual; |
41 | 625a5bef | Adam Litke | uint64_t stats[VIRTIO_BALLOON_S_NR]; |
42 | 625a5bef | Adam Litke | VirtQueueElement stats_vq_elem; |
43 | 625a5bef | Adam Litke | size_t stats_vq_offset; |
44 | 625a5bef | Adam Litke | MonitorCompletion *stats_callback; |
45 | 625a5bef | Adam Litke | void *stats_opaque_callback_data;
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46 | bd322087 | aliguori | } VirtIOBalloon; |
47 | bd322087 | aliguori | |
48 | bd322087 | aliguori | static VirtIOBalloon *to_virtio_balloon(VirtIODevice *vdev)
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49 | bd322087 | aliguori | { |
50 | bd322087 | aliguori | return (VirtIOBalloon *)vdev;
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51 | bd322087 | aliguori | } |
52 | bd322087 | aliguori | |
53 | bd322087 | aliguori | static void balloon_page(void *addr, int deflate) |
54 | bd322087 | aliguori | { |
55 | bd322087 | aliguori | #if defined(__linux__)
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56 | bd322087 | aliguori | if (!kvm_enabled() || kvm_has_sync_mmu())
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57 | e78815a5 | Andreas Färber | qemu_madvise(addr, TARGET_PAGE_SIZE, |
58 | e78815a5 | Andreas Färber | deflate ? QEMU_MADV_WILLNEED : QEMU_MADV_DONTNEED); |
59 | bd322087 | aliguori | #endif
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60 | bd322087 | aliguori | } |
61 | bd322087 | aliguori | |
62 | 625a5bef | Adam Litke | /*
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63 | 625a5bef | Adam Litke | * reset_stats - Mark all items in the stats array as unset
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64 | 625a5bef | Adam Litke | *
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65 | 625a5bef | Adam Litke | * This function needs to be called at device intialization and before
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66 | 625a5bef | Adam Litke | * before updating to a set of newly-generated stats. This will ensure that no
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67 | 625a5bef | Adam Litke | * stale values stick around in case the guest reports a subset of the supported
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68 | 625a5bef | Adam Litke | * statistics.
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69 | 625a5bef | Adam Litke | */
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70 | 625a5bef | Adam Litke | static inline void reset_stats(VirtIOBalloon *dev) |
71 | 625a5bef | Adam Litke | { |
72 | 625a5bef | Adam Litke | int i;
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73 | 625a5bef | Adam Litke | for (i = 0; i < VIRTIO_BALLOON_S_NR; dev->stats[i++] = -1); |
74 | 625a5bef | Adam Litke | } |
75 | 625a5bef | Adam Litke | |
76 | 625a5bef | Adam Litke | static void stat_put(QDict *dict, const char *label, uint64_t val) |
77 | 625a5bef | Adam Litke | { |
78 | 625a5bef | Adam Litke | if (val != -1) |
79 | 625a5bef | Adam Litke | qdict_put(dict, label, qint_from_int(val)); |
80 | 625a5bef | Adam Litke | } |
81 | 625a5bef | Adam Litke | |
82 | 625a5bef | Adam Litke | static QObject *get_stats_qobject(VirtIOBalloon *dev)
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83 | 625a5bef | Adam Litke | { |
84 | 625a5bef | Adam Litke | QDict *dict = qdict_new(); |
85 | bd12ff9d | Adam Litke | uint64_t actual = ram_size - ((uint64_t) dev->actual << |
86 | bd12ff9d | Adam Litke | VIRTIO_BALLOON_PFN_SHIFT); |
87 | 625a5bef | Adam Litke | |
88 | 625a5bef | Adam Litke | stat_put(dict, "actual", actual);
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89 | 07b0403d | Eduardo Habkost | #if ENABLE_GUEST_STATS
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90 | 625a5bef | Adam Litke | stat_put(dict, "mem_swapped_in", dev->stats[VIRTIO_BALLOON_S_SWAP_IN]);
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91 | 625a5bef | Adam Litke | stat_put(dict, "mem_swapped_out", dev->stats[VIRTIO_BALLOON_S_SWAP_OUT]);
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92 | 625a5bef | Adam Litke | stat_put(dict, "major_page_faults", dev->stats[VIRTIO_BALLOON_S_MAJFLT]);
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93 | 625a5bef | Adam Litke | stat_put(dict, "minor_page_faults", dev->stats[VIRTIO_BALLOON_S_MINFLT]);
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94 | 625a5bef | Adam Litke | stat_put(dict, "free_mem", dev->stats[VIRTIO_BALLOON_S_MEMFREE]);
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95 | 625a5bef | Adam Litke | stat_put(dict, "total_mem", dev->stats[VIRTIO_BALLOON_S_MEMTOT]);
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96 | 07b0403d | Eduardo Habkost | #endif
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97 | 625a5bef | Adam Litke | |
98 | 625a5bef | Adam Litke | return QOBJECT(dict);
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99 | 625a5bef | Adam Litke | } |
100 | 625a5bef | Adam Litke | |
101 | bd322087 | aliguori | static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) |
102 | bd322087 | aliguori | { |
103 | bd322087 | aliguori | VirtIOBalloon *s = to_virtio_balloon(vdev); |
104 | bd322087 | aliguori | VirtQueueElement elem; |
105 | bd322087 | aliguori | |
106 | bd322087 | aliguori | while (virtqueue_pop(vq, &elem)) {
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107 | bd322087 | aliguori | size_t offset = 0;
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108 | bd322087 | aliguori | uint32_t pfn; |
109 | bd322087 | aliguori | |
110 | fa6111f2 | Amit Shah | while (iov_to_buf(elem.out_sg, elem.out_num, &pfn, offset, 4) == 4) { |
111 | c227f099 | Anthony Liguori | ram_addr_t pa; |
112 | c227f099 | Anthony Liguori | ram_addr_t addr; |
113 | bd322087 | aliguori | |
114 | c227f099 | Anthony Liguori | pa = (ram_addr_t)ldl_p(&pfn) << VIRTIO_BALLOON_PFN_SHIFT; |
115 | bd322087 | aliguori | offset += 4;
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116 | bd322087 | aliguori | |
117 | bd322087 | aliguori | addr = cpu_get_physical_page_desc(pa); |
118 | bd322087 | aliguori | if ((addr & ~TARGET_PAGE_MASK) != IO_MEM_RAM)
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119 | bd322087 | aliguori | continue;
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120 | bd322087 | aliguori | |
121 | 5c130f65 | pbrook | /* Using qemu_get_ram_ptr is bending the rules a bit, but
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122 | 5c130f65 | pbrook | should be OK because we only want a single page. */
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123 | 5c130f65 | pbrook | balloon_page(qemu_get_ram_ptr(addr), !!(vq == s->dvq)); |
124 | bd322087 | aliguori | } |
125 | bd322087 | aliguori | |
126 | bd322087 | aliguori | virtqueue_push(vq, &elem, offset); |
127 | bd322087 | aliguori | virtio_notify(vdev, vq); |
128 | bd322087 | aliguori | } |
129 | bd322087 | aliguori | } |
130 | bd322087 | aliguori | |
131 | 625a5bef | Adam Litke | static void complete_stats_request(VirtIOBalloon *vb) |
132 | 625a5bef | Adam Litke | { |
133 | 625a5bef | Adam Litke | QObject *stats; |
134 | 625a5bef | Adam Litke | |
135 | 625a5bef | Adam Litke | if (!vb->stats_opaque_callback_data)
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136 | 625a5bef | Adam Litke | return;
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137 | 625a5bef | Adam Litke | |
138 | 625a5bef | Adam Litke | stats = get_stats_qobject(vb); |
139 | 625a5bef | Adam Litke | vb->stats_callback(vb->stats_opaque_callback_data, stats); |
140 | 625a5bef | Adam Litke | qobject_decref(stats); |
141 | 625a5bef | Adam Litke | vb->stats_opaque_callback_data = NULL;
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142 | 625a5bef | Adam Litke | vb->stats_callback = NULL;
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143 | 625a5bef | Adam Litke | } |
144 | 625a5bef | Adam Litke | |
145 | 625a5bef | Adam Litke | static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq) |
146 | 625a5bef | Adam Litke | { |
147 | 625a5bef | Adam Litke | VirtIOBalloon *s = DO_UPCAST(VirtIOBalloon, vdev, vdev); |
148 | 625a5bef | Adam Litke | VirtQueueElement *elem = &s->stats_vq_elem; |
149 | 625a5bef | Adam Litke | VirtIOBalloonStat stat; |
150 | 625a5bef | Adam Litke | size_t offset = 0;
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151 | 625a5bef | Adam Litke | |
152 | 625a5bef | Adam Litke | if (!virtqueue_pop(vq, elem)) {
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153 | 625a5bef | Adam Litke | return;
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154 | 625a5bef | Adam Litke | } |
155 | 625a5bef | Adam Litke | |
156 | 625a5bef | Adam Litke | /* Initialize the stats to get rid of any stale values. This is only
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157 | 625a5bef | Adam Litke | * needed to handle the case where a guest supports fewer stats than it
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158 | 625a5bef | Adam Litke | * used to (ie. it has booted into an old kernel).
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159 | 625a5bef | Adam Litke | */
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160 | 625a5bef | Adam Litke | reset_stats(s); |
161 | 625a5bef | Adam Litke | |
162 | fa6111f2 | Amit Shah | while (iov_to_buf(elem->out_sg, elem->out_num, &stat, offset, sizeof(stat)) |
163 | fa6111f2 | Amit Shah | == sizeof(stat)) {
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164 | 625a5bef | Adam Litke | uint16_t tag = tswap16(stat.tag); |
165 | 625a5bef | Adam Litke | uint64_t val = tswap64(stat.val); |
166 | 625a5bef | Adam Litke | |
167 | 625a5bef | Adam Litke | offset += sizeof(stat);
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168 | 625a5bef | Adam Litke | if (tag < VIRTIO_BALLOON_S_NR)
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169 | 625a5bef | Adam Litke | s->stats[tag] = val; |
170 | 625a5bef | Adam Litke | } |
171 | 625a5bef | Adam Litke | s->stats_vq_offset = offset; |
172 | 625a5bef | Adam Litke | |
173 | 625a5bef | Adam Litke | complete_stats_request(s); |
174 | 625a5bef | Adam Litke | } |
175 | 625a5bef | Adam Litke | |
176 | bd322087 | aliguori | static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data) |
177 | bd322087 | aliguori | { |
178 | bd322087 | aliguori | VirtIOBalloon *dev = to_virtio_balloon(vdev); |
179 | bd322087 | aliguori | struct virtio_balloon_config config;
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180 | bd322087 | aliguori | |
181 | bd322087 | aliguori | config.num_pages = cpu_to_le32(dev->num_pages); |
182 | bd322087 | aliguori | config.actual = cpu_to_le32(dev->actual); |
183 | bd322087 | aliguori | |
184 | bd322087 | aliguori | memcpy(config_data, &config, 8);
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185 | bd322087 | aliguori | } |
186 | bd322087 | aliguori | |
187 | bd322087 | aliguori | static void virtio_balloon_set_config(VirtIODevice *vdev, |
188 | bd322087 | aliguori | const uint8_t *config_data)
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189 | bd322087 | aliguori | { |
190 | bd322087 | aliguori | VirtIOBalloon *dev = to_virtio_balloon(vdev); |
191 | bd322087 | aliguori | struct virtio_balloon_config config;
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192 | bd322087 | aliguori | memcpy(&config, config_data, 8);
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193 | e54f1771 | Alexey Kardashevskiy | dev->actual = le32_to_cpu(config.actual); |
194 | bd322087 | aliguori | } |
195 | bd322087 | aliguori | |
196 | 8172539d | Michael S. Tsirkin | static uint32_t virtio_balloon_get_features(VirtIODevice *vdev, uint32_t f)
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197 | bd322087 | aliguori | { |
198 | 625a5bef | Adam Litke | f |= (1 << VIRTIO_BALLOON_F_STATS_VQ);
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199 | 8172539d | Michael S. Tsirkin | return f;
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200 | bd322087 | aliguori | } |
201 | bd322087 | aliguori | |
202 | 625a5bef | Adam Litke | static void virtio_balloon_to_target(void *opaque, ram_addr_t target, |
203 | 625a5bef | Adam Litke | MonitorCompletion cb, void *cb_data)
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204 | bd322087 | aliguori | { |
205 | bd322087 | aliguori | VirtIOBalloon *dev = opaque; |
206 | bd322087 | aliguori | |
207 | bd322087 | aliguori | if (target > ram_size)
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208 | bd322087 | aliguori | target = ram_size; |
209 | bd322087 | aliguori | |
210 | bd322087 | aliguori | if (target) {
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211 | bd322087 | aliguori | dev->num_pages = (ram_size - target) >> VIRTIO_BALLOON_PFN_SHIFT; |
212 | bd322087 | aliguori | virtio_notify_config(&dev->vdev); |
213 | 625a5bef | Adam Litke | } else {
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214 | 625a5bef | Adam Litke | /* For now, only allow one request at a time. This restriction can be
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215 | 625a5bef | Adam Litke | * removed later by queueing callback and data pairs.
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216 | 625a5bef | Adam Litke | */
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217 | 625a5bef | Adam Litke | if (dev->stats_callback != NULL) { |
218 | 625a5bef | Adam Litke | return;
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219 | 625a5bef | Adam Litke | } |
220 | 625a5bef | Adam Litke | dev->stats_callback = cb; |
221 | 625a5bef | Adam Litke | dev->stats_opaque_callback_data = cb_data; |
222 | 07b0403d | Eduardo Habkost | if (ENABLE_GUEST_STATS && (dev->vdev.guest_features & (1 << VIRTIO_BALLOON_F_STATS_VQ))) { |
223 | 625a5bef | Adam Litke | virtqueue_push(dev->svq, &dev->stats_vq_elem, dev->stats_vq_offset); |
224 | 625a5bef | Adam Litke | virtio_notify(&dev->vdev, dev->svq); |
225 | 625a5bef | Adam Litke | } else {
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226 | 625a5bef | Adam Litke | /* Stats are not supported. Clear out any stale values that might
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227 | 625a5bef | Adam Litke | * have been set by a more featureful guest kernel.
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228 | 625a5bef | Adam Litke | */
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229 | 625a5bef | Adam Litke | reset_stats(dev); |
230 | 625a5bef | Adam Litke | complete_stats_request(dev); |
231 | 625a5bef | Adam Litke | } |
232 | bd322087 | aliguori | } |
233 | bd322087 | aliguori | } |
234 | bd322087 | aliguori | |
235 | bd322087 | aliguori | static void virtio_balloon_save(QEMUFile *f, void *opaque) |
236 | bd322087 | aliguori | { |
237 | bd322087 | aliguori | VirtIOBalloon *s = opaque; |
238 | bd322087 | aliguori | |
239 | bd322087 | aliguori | virtio_save(&s->vdev, f); |
240 | bd322087 | aliguori | |
241 | bd322087 | aliguori | qemu_put_be32(f, s->num_pages); |
242 | bd322087 | aliguori | qemu_put_be32(f, s->actual); |
243 | bd322087 | aliguori | } |
244 | bd322087 | aliguori | |
245 | bd322087 | aliguori | static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id) |
246 | bd322087 | aliguori | { |
247 | bd322087 | aliguori | VirtIOBalloon *s = opaque; |
248 | bd322087 | aliguori | |
249 | bd322087 | aliguori | if (version_id != 1) |
250 | bd322087 | aliguori | return -EINVAL;
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251 | bd322087 | aliguori | |
252 | bd322087 | aliguori | virtio_load(&s->vdev, f); |
253 | bd322087 | aliguori | |
254 | bd322087 | aliguori | s->num_pages = qemu_get_be32(f); |
255 | bd322087 | aliguori | s->actual = qemu_get_be32(f); |
256 | bd322087 | aliguori | return 0; |
257 | bd322087 | aliguori | } |
258 | bd322087 | aliguori | |
259 | 53c25cea | Paul Brook | VirtIODevice *virtio_balloon_init(DeviceState *dev) |
260 | bd322087 | aliguori | { |
261 | bd322087 | aliguori | VirtIOBalloon *s; |
262 | bd322087 | aliguori | |
263 | 53c25cea | Paul Brook | s = (VirtIOBalloon *)virtio_common_init("virtio-balloon",
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264 | 53c25cea | Paul Brook | VIRTIO_ID_BALLOON, |
265 | 53c25cea | Paul Brook | 8, sizeof(VirtIOBalloon)); |
266 | bd322087 | aliguori | |
267 | bd322087 | aliguori | s->vdev.get_config = virtio_balloon_get_config; |
268 | bd322087 | aliguori | s->vdev.set_config = virtio_balloon_set_config; |
269 | bd322087 | aliguori | s->vdev.get_features = virtio_balloon_get_features; |
270 | bd322087 | aliguori | |
271 | bd322087 | aliguori | s->ivq = virtio_add_queue(&s->vdev, 128, virtio_balloon_handle_output);
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272 | bd322087 | aliguori | s->dvq = virtio_add_queue(&s->vdev, 128, virtio_balloon_handle_output);
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273 | 625a5bef | Adam Litke | s->svq = virtio_add_queue(&s->vdev, 128, virtio_balloon_receive_stats);
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274 | bd322087 | aliguori | |
275 | 625a5bef | Adam Litke | reset_stats(s); |
276 | bd322087 | aliguori | qemu_add_balloon_handler(virtio_balloon_to_target, s); |
277 | bd322087 | aliguori | |
278 | 0be71e32 | Alex Williamson | register_savevm(dev, "virtio-balloon", -1, 1, |
279 | 0be71e32 | Alex Williamson | virtio_balloon_save, virtio_balloon_load, s); |
280 | bd322087 | aliguori | |
281 | 53c25cea | Paul Brook | return &s->vdev;
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282 | bd322087 | aliguori | } |