summaryrefslogtreecommitdiffstats
path: root/0001-virt-vbox-Add-support-for-the-new-VBG_IOCTL_ACQUIRE_.patch
blob: c001fe5d417b6bf9e285b90d38a1b6ccbc1ec2c5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Tue, 19 May 2020 18:04:30 +0200
Subject: [PATCH] virt: vbox: Add support for the new
 VBG_IOCTL_ACQUIRE_GUEST_CAPABILITIES ioctl

Add support for the new VBG_IOCTL_ACQUIRE_GUEST_CAPABILITIES ioctl, this
is necessary for automatic resizing of the guest resolution to match the
VM-window size to work with the new VMSVGA virtual GPU which is now the
new default in VirtualBox.

BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1789545
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Upstream Status: https://lore.kernel.org/lkml/20200520195440.38759-1-hdegoede@redhat.com/
---
 drivers/virt/vboxguest/vboxguest_core.c | 163 +++++++++++++++++++++++-
 drivers/virt/vboxguest/vboxguest_core.h |  14 ++
 include/uapi/linux/vboxguest.h          |  24 ++++
 3 files changed, 200 insertions(+), 1 deletion(-)

diff --git a/drivers/virt/vboxguest/vboxguest_core.c b/drivers/virt/vboxguest/vboxguest_core.c
index 15b3cb618c6e..4f1addaa3f6f 100644
--- a/drivers/virt/vboxguest/vboxguest_core.c
+++ b/drivers/virt/vboxguest/vboxguest_core.c
@@ -679,7 +679,7 @@ static int vbg_set_host_capabilities(struct vbg_dev *gdev,

 	WARN_ON(!mutex_is_locked(&gdev->session_mutex));

-	caps = gdev->set_guest_caps_tracker.mask;
+	caps = gdev->acquired_guest_caps | gdev->set_guest_caps_tracker.mask;

 	if (gdev->guest_caps_host == caps)
 		return 0;
@@ -703,6 +703,113 @@ static int vbg_set_host_capabilities(struct vbg_dev *gdev,
 	return vbg_status_code_to_errno(rc);
 }

+/**
+ * Acquire (get exclusive access) guest capabilities for a session.
+ * Takes the session mutex.
+ * Return: 0 or negative errno value.
+ * @gdev:			The Guest extension device.
+ * @session:			The session.
+ * @flags:			Flags (VBGL_IOC_AGC_FLAGS_XXX).
+ * @or_mask:			The capabilities to add.
+ * @not_mask:			The capabilities to remove.
+ * @session_termination:	Set if we're called by the session cleanup code.
+ *				This tweaks the error handling so we perform
+ *				proper session cleanup even if the host
+ *				misbehaves.
+ */
+static int vbg_acquire_session_capabilities(struct vbg_dev *gdev,
+					    struct vbg_session *session,
+					    u32 or_mask, u32 not_mask,
+					    u32 flags, bool session_termination)
+{
+	unsigned long irqflags;
+	bool wakeup = false;
+	int ret = 0;
+
+	mutex_lock(&gdev->session_mutex);
+
+	if (gdev->set_guest_caps_tracker.mask & or_mask) {
+		vbg_err("%s error: cannot acquire caps which are currently set\n",
+			__func__);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Mark any caps in the or_mask as now being in acquire-mode. Note
+	 * once caps are in acquire_mode they always stay in this mode.
+	 * This impacts event handling, so we take the event-lock.
+	 */
+	spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+	gdev->acquire_mode_guest_caps |= or_mask;
+	spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+
+	/* If we only have to switch the caps to acquire mode, we're done. */
+	if (flags & VBGL_IOC_AGC_FLAGS_CONFIG_ACQUIRE_MODE)
+		goto out;
+
+	not_mask &= ~or_mask; /* or_mask takes priority over not_mask */
+	not_mask &= session->acquired_guest_caps;
+	or_mask &= ~session->acquired_guest_caps;
+
+	if (or_mask == 0 && not_mask == 0)
+		goto out;
+
+	if (gdev->acquired_guest_caps & or_mask) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	gdev->acquired_guest_caps |= or_mask;
+	gdev->acquired_guest_caps &= ~not_mask;
+	/* session->acquired_guest_caps impacts event handling, take the lock */
+	spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+	session->acquired_guest_caps |= or_mask;
+	session->acquired_guest_caps &= ~not_mask;
+	spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+
+	ret = vbg_set_host_capabilities(gdev, session, session_termination);
+	/* Roll back on failure, unless it's session termination time. */
+	if (ret < 0 && !session_termination) {
+		gdev->acquired_guest_caps &= ~or_mask;
+		gdev->acquired_guest_caps |= not_mask;
+		spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+		session->acquired_guest_caps &= ~or_mask;
+		session->acquired_guest_caps |= not_mask;
+		spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+	}
+
+	/*
+	 * If we added a capability, check if that means some other thread in
+	 * our session should be unblocked because there are events pending
+	 * (the result of vbg_get_allowed_event_mask_for_session() may change).
+	 *
+	 * HACK ALERT! When the seamless support capability is added we generate
+	 *	a seamless change event so that the ring-3 client can sync with
+	 *	the seamless state.
+	 */
+	if (ret == 0 && or_mask != 0) {
+		spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+
+		if (or_mask & VMMDEV_GUEST_SUPPORTS_SEAMLESS)
+			gdev->pending_events |=
+				VMMDEV_EVENT_SEAMLESS_MODE_CHANGE_REQUEST;
+
+		if (gdev->pending_events)
+			wakeup = true;
+
+		spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+
+		if (wakeup)
+			wake_up(&gdev->event_wq);
+	}
+
+out:
+	mutex_unlock(&gdev->session_mutex);
+
+	return ret;
+}
+
 /**
  * Sets the guest capabilities for a session. Takes the session spinlock.
  * Return: 0 or negative errno value.
@@ -725,6 +832,13 @@ static int vbg_set_session_capabilities(struct vbg_dev *gdev,

 	mutex_lock(&gdev->session_mutex);

+	if (gdev->acquire_mode_guest_caps & or_mask) {
+		vbg_err("%s error: cannot set caps which are in acquire_mode\n",
+			__func__);
+		ret = -EBUSY;
+		goto out;
+	}
+
 	/* Apply the changes to the session mask. */
 	previous = session->set_guest_caps;
 	session->set_guest_caps |= or_mask;
@@ -962,6 +1076,7 @@ void vbg_core_close_session(struct vbg_session *session)
 	struct vbg_dev *gdev = session->gdev;
 	int i, rc;

+	vbg_acquire_session_capabilities(gdev, session, 0, U32_MAX, 0, true);
 	vbg_set_session_capabilities(gdev, session, 0, U32_MAX, true);
 	vbg_set_session_event_filter(gdev, session, 0, U32_MAX, true);

@@ -1019,6 +1134,25 @@ static int vbg_ioctl_driver_version_info(
 	return 0;
 }

+/* Must be called with the event_lock held */
+static u32 vbg_get_allowed_event_mask_for_session(struct vbg_dev *gdev,
+						  struct vbg_session *session)
+{
+	u32 acquire_mode_caps = gdev->acquire_mode_guest_caps;
+	u32 session_acquired_caps = session->acquired_guest_caps;
+	u32 allowed_events = VMMDEV_EVENT_VALID_EVENT_MASK;
+
+	if ((acquire_mode_caps & VMMDEV_GUEST_SUPPORTS_GRAPHICS) &&
+	    !(session_acquired_caps & VMMDEV_GUEST_SUPPORTS_GRAPHICS))
+		allowed_events &= ~VMMDEV_EVENT_DISPLAY_CHANGE_REQUEST;
+
+	if ((acquire_mode_caps & VMMDEV_GUEST_SUPPORTS_SEAMLESS) &&
+	    !(session_acquired_caps & VMMDEV_GUEST_SUPPORTS_SEAMLESS))
+		allowed_events &= ~VMMDEV_EVENT_SEAMLESS_MODE_CHANGE_REQUEST;
+
+	return allowed_events;
+}
+
 static bool vbg_wait_event_cond(struct vbg_dev *gdev,
 				struct vbg_session *session,
 				u32 event_mask)
@@ -1030,6 +1164,7 @@ static bool vbg_wait_event_cond(struct vbg_dev *gdev,
 	spin_lock_irqsave(&gdev->event_spinlock, flags);

 	events = gdev->pending_events & event_mask;
+	events &= vbg_get_allowed_event_mask_for_session(gdev, session);
 	wakeup = events || session->cancel_waiters;

 	spin_unlock_irqrestore(&gdev->event_spinlock, flags);
@@ -1044,6 +1179,7 @@ static u32 vbg_consume_events_locked(struct vbg_dev *gdev,
 {
 	u32 events = gdev->pending_events & event_mask;

+	events &= vbg_get_allowed_event_mask_for_session(gdev, session);
 	gdev->pending_events &= ~events;
 	return events;
 }
@@ -1445,6 +1581,29 @@ static int vbg_ioctl_change_filter_mask(struct vbg_dev *gdev,
 					    false);
 }

+static int vbg_ioctl_acquire_guest_capabilities(struct vbg_dev *gdev,
+	     struct vbg_session *session,
+	     struct vbg_ioctl_acquire_guest_caps *caps)
+{
+	u32 flags, or_mask, not_mask;
+
+	if (vbg_ioctl_chk(&caps->hdr, sizeof(caps->u.in), 0))
+		return -EINVAL;
+
+	flags = caps->u.in.flags;
+	or_mask = caps->u.in.or_mask;
+	not_mask = caps->u.in.not_mask;
+
+	if (flags & ~VBGL_IOC_AGC_FLAGS_VALID_MASK)
+		return -EINVAL;
+
+	if ((or_mask | not_mask) & ~VMMDEV_GUEST_CAPABILITIES_MASK)
+		return -EINVAL;
+
+	return vbg_acquire_session_capabilities(gdev, session, or_mask,
+						not_mask, flags, false);
+}
+
 static int vbg_ioctl_change_guest_capabilities(struct vbg_dev *gdev,
 	     struct vbg_session *session, struct vbg_ioctl_set_guest_caps *caps)
 {
@@ -1554,6 +1713,8 @@ int vbg_core_ioctl(struct vbg_session *session, unsigned int req, void *data)
 		return vbg_ioctl_interrupt_all_wait_events(gdev, session, data);
 	case VBG_IOCTL_CHANGE_FILTER_MASK:
 		return vbg_ioctl_change_filter_mask(gdev, session, data);
+	case VBG_IOCTL_ACQUIRE_GUEST_CAPABILITIES:
+		return vbg_ioctl_acquire_guest_capabilities(gdev, session, data);
 	case VBG_IOCTL_CHANGE_GUEST_CAPABILITIES:
 		return vbg_ioctl_change_guest_capabilities(gdev, session, data);
 	case VBG_IOCTL_CHECK_BALLOON:
diff --git a/drivers/virt/vboxguest/vboxguest_core.h b/drivers/virt/vboxguest/vboxguest_core.h
index dc745a033164..ab4bf64e2cec 100644
--- a/drivers/virt/vboxguest/vboxguest_core.h
+++ b/drivers/virt/vboxguest/vboxguest_core.h
@@ -117,6 +117,15 @@ struct vbg_dev {
 	 */
 	u32 event_filter_host;

+	/**
+	 * Guest capabilities which have been switched to acquire_mode.
+	 */
+	u32 acquire_mode_guest_caps;
+	/**
+	 * Guest capabilities acquired by vbg_acquire_session_capabilities().
+	 * Only one session can acquire a capability at a time.
+	 */
+	u32 acquired_guest_caps;
 	/**
 	 * Usage counters for guest capabilities requested through
 	 * vbg_set_session_capabilities(). Indexed by capability bit
@@ -164,6 +173,11 @@ struct vbg_session {
 	 * host filter. Protected by vbg_gdev.session_mutex.
 	 */
 	u32 event_filter;
+	/**
+	 * Guest capabilities acquired by vbg_acquire_session_capabilities().
+	 * Only one session can acquire a capability at a time.
+	 */
+	u32 acquired_guest_caps;
 	/**
 	 * Guest capabilities set through vbg_set_session_capabilities().
 	 * A capability claimed by any guest session will be reported to the
diff --git a/include/uapi/linux/vboxguest.h b/include/uapi/linux/vboxguest.h
index f79d7abe27db..15125f6ec60d 100644
--- a/include/uapi/linux/vboxguest.h
+++ b/include/uapi/linux/vboxguest.h
@@ -257,6 +257,30 @@ VMMDEV_ASSERT_SIZE(vbg_ioctl_change_filter, 24 + 8);
 	_IOWR('V', 12, struct vbg_ioctl_change_filter)


+/** VBG_IOCTL_ACQUIRE_GUEST_CAPABILITIES data structure. */
+struct vbg_ioctl_acquire_guest_caps {
+	/** The header. */
+	struct vbg_ioctl_hdr hdr;
+	union {
+		struct {
+			/** Flags (VBGL_IOC_AGC_FLAGS_XXX). */
+			__u32 flags;
+			/** Capabilities to set (VMMDEV_GUEST_SUPPORTS_XXX). */
+			__u32 or_mask;
+			/** Capabilities to drop (VMMDEV_GUEST_SUPPORTS_XXX). */
+			__u32 not_mask;
+		} in;
+	} u;
+};
+VMMDEV_ASSERT_SIZE(vbg_ioctl_acquire_guest_caps, 24 + 12);
+
+#define VBGL_IOC_AGC_FLAGS_CONFIG_ACQUIRE_MODE		0x00000001
+#define VBGL_IOC_AGC_FLAGS_VALID_MASK			0x00000001
+
+#define VBG_IOCTL_ACQUIRE_GUEST_CAPABILITIES \
+	_IOWR('V', 13, struct vbg_ioctl_acquire_guest_caps)
+
+
 /** VBG_IOCTL_CHANGE_GUEST_CAPABILITIES data structure. */
 struct vbg_ioctl_set_guest_caps {
 	/** The header. */
-- 
2.26.2