Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 549 insertions, 0 deletions

diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
new file mode 100644
index 000000000..da51b5078
--- /dev/null
+++ b/drivers/hv/connection.c
@@ -0,0 +1,549 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/hyperv.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <linux/set_memory.h>
+#include <asm/mshyperv.h>
+
+#include "hyperv_vmbus.h"
+
+
+struct vmbus_connection vmbus_connection = {
+	.conn_state		= DISCONNECTED,
+	.unload_event		= COMPLETION_INITIALIZER(
+				  vmbus_connection.unload_event),
+	.next_gpadl_handle	= ATOMIC_INIT(0xE1E10),
+
+	.ready_for_suspend_event = COMPLETION_INITIALIZER(
+				  vmbus_connection.ready_for_suspend_event),
+	.ready_for_resume_event	= COMPLETION_INITIALIZER(
+				  vmbus_connection.ready_for_resume_event),
+};
+EXPORT_SYMBOL_GPL(vmbus_connection);
+
+/*
+ * Negotiated protocol version with the host.
+ */
+__u32 vmbus_proto_version;
+EXPORT_SYMBOL_GPL(vmbus_proto_version);
+
+/*
+ * Table of VMBus versions listed from newest to oldest.
+ * VERSION_WIN7 and VERSION_WS2008 are no longer supported in
+ * Linux guests and are not listed.
+ */
+static __u32 vmbus_versions[] = {
+	VERSION_WIN10_V5_3,
+	VERSION_WIN10_V5_2,
+	VERSION_WIN10_V5_1,
+	VERSION_WIN10_V5,
+	VERSION_WIN10_V4_1,
+	VERSION_WIN10,
+	VERSION_WIN8_1,
+	VERSION_WIN8
+};
+
+/*
+ * Maximal VMBus protocol version guests can negotiate.  Useful to cap the
+ * VMBus version for testing and debugging purpose.
+ */
+static uint max_version = VERSION_WIN10_V5_3;
+
+module_param(max_version, uint, S_IRUGO);
+MODULE_PARM_DESC(max_version,
+		 "Maximal VMBus protocol version which can be negotiated");
+
+int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version)
+{
+	int ret = 0;
+	struct vmbus_channel_initiate_contact *msg;
+	unsigned long flags;
+
+	init_completion(&msginfo->waitevent);
+
+	msg = (struct vmbus_channel_initiate_contact *)msginfo->msg;
+
+	memset(msg, 0, sizeof(*msg));
+	msg->header.msgtype = CHANNELMSG_INITIATE_CONTACT;
+	msg->vmbus_version_requested = version;
+
+	/*
+	 * VMBus protocol 5.0 (VERSION_WIN10_V5) and higher require that we must
+	 * use VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message,
+	 * and for subsequent messages, we must use the Message Connection ID
+	 * field in the host-returned Version Response Message. And, with
+	 * VERSION_WIN10_V5 and higher, we don't use msg->interrupt_page, but we
+	 * tell the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for
+	 * compatibility.
+	 *
+	 * On old hosts, we should always use VMBUS_MESSAGE_CONNECTION_ID (1).
+	 */
+	if (version >= VERSION_WIN10_V5) {
+		msg->msg_sint = VMBUS_MESSAGE_SINT;
+		vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID_4;
+	} else {
+		msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
+		vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID;
+	}
+
+	msg->monitor_page1 = vmbus_connection.monitor_pages_pa[0];
+	msg->monitor_page2 = vmbus_connection.monitor_pages_pa[1];
+
+	msg->target_vcpu = hv_cpu_number_to_vp_number(VMBUS_CONNECT_CPU);
+
+	/*
+	 * Add to list before we send the request since we may
+	 * receive the response before returning from this routine
+	 */
+	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+	list_add_tail(&msginfo->msglistentry,
+		      &vmbus_connection.chn_msg_list);
+
+	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+	ret = vmbus_post_msg(msg,
+			     sizeof(struct vmbus_channel_initiate_contact),
+			     true);
+
+	trace_vmbus_negotiate_version(msg, ret);
+
+	if (ret != 0) {
+		spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+		list_del(&msginfo->msglistentry);
+		spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock,
+					flags);
+		return ret;
+	}
+
+	/* Wait for the connection response */
+	wait_for_completion(&msginfo->waitevent);
+
+	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+	list_del(&msginfo->msglistentry);
+	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+	/* Check if successful */
+	if (msginfo->response.version_response.version_supported) {
+		vmbus_connection.conn_state = CONNECTED;
+
+		if (version >= VERSION_WIN10_V5)
+			vmbus_connection.msg_conn_id =
+				msginfo->response.version_response.msg_conn_id;
+	} else {
+		return -ECONNREFUSED;
+	}
+
+	return ret;
+}
+
+/*
+ * vmbus_connect - Sends a connect request on the partition service connection
+ */
+int vmbus_connect(void)
+{
+	struct vmbus_channel_msginfo *msginfo = NULL;
+	int i, ret = 0;
+	__u32 version;
+
+	/* Initialize the vmbus connection */
+	vmbus_connection.conn_state = CONNECTING;
+	vmbus_connection.work_queue = create_workqueue("hv_vmbus_con");
+	if (!vmbus_connection.work_queue) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	vmbus_connection.rescind_work_queue =
+		create_workqueue("hv_vmbus_rescind");
+	if (!vmbus_connection.rescind_work_queue) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+	vmbus_connection.ignore_any_offer_msg = false;
+
+	vmbus_connection.handle_primary_chan_wq =
+		create_workqueue("hv_pri_chan");
+	if (!vmbus_connection.handle_primary_chan_wq) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	vmbus_connection.handle_sub_chan_wq =
+		create_workqueue("hv_sub_chan");
+	if (!vmbus_connection.handle_sub_chan_wq) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	INIT_LIST_HEAD(&vmbus_connection.chn_msg_list);
+	spin_lock_init(&vmbus_connection.channelmsg_lock);
+
+	INIT_LIST_HEAD(&vmbus_connection.chn_list);
+	mutex_init(&vmbus_connection.channel_mutex);
+
+	/*
+	 * Setup the vmbus event connection for channel interrupt
+	 * abstraction stuff
+	 */
+	vmbus_connection.int_page =
+	(void *)hv_alloc_hyperv_zeroed_page();
+	if (vmbus_connection.int_page == NULL) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	vmbus_connection.recv_int_page = vmbus_connection.int_page;
+	vmbus_connection.send_int_page =
+		(void *)((unsigned long)vmbus_connection.int_page +
+			(HV_HYP_PAGE_SIZE >> 1));
+
+	/*
+	 * Setup the monitor notification facility. The 1st page for
+	 * parent->child and the 2nd page for child->parent
+	 */
+	vmbus_connection.monitor_pages[0] = (void *)hv_alloc_hyperv_zeroed_page();
+	vmbus_connection.monitor_pages[1] = (void *)hv_alloc_hyperv_zeroed_page();
+	if ((vmbus_connection.monitor_pages[0] == NULL) ||
+	    (vmbus_connection.monitor_pages[1] == NULL)) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	vmbus_connection.monitor_pages_original[0]
+		= vmbus_connection.monitor_pages[0];
+	vmbus_connection.monitor_pages_original[1]
+		= vmbus_connection.monitor_pages[1];
+	vmbus_connection.monitor_pages_pa[0]
+		= virt_to_phys(vmbus_connection.monitor_pages[0]);
+	vmbus_connection.monitor_pages_pa[1]
+		= virt_to_phys(vmbus_connection.monitor_pages[1]);
+
+	if (hv_is_isolation_supported()) {
+		ret = set_memory_decrypted((unsigned long)
+					   vmbus_connection.monitor_pages[0],
+					   1);
+		ret |= set_memory_decrypted((unsigned long)
+					    vmbus_connection.monitor_pages[1],
+					    1);
+		if (ret)
+			goto cleanup;
+
+		/*
+		 * Isolation VM with AMD SNP needs to access monitor page via
+		 * address space above shared gpa boundary.
+		 */
+		if (hv_isolation_type_snp()) {
+			vmbus_connection.monitor_pages_pa[0] +=
+				ms_hyperv.shared_gpa_boundary;
+			vmbus_connection.monitor_pages_pa[1] +=
+				ms_hyperv.shared_gpa_boundary;
+
+			vmbus_connection.monitor_pages[0]
+				= memremap(vmbus_connection.monitor_pages_pa[0],
+					   HV_HYP_PAGE_SIZE,
+					   MEMREMAP_WB);
+			if (!vmbus_connection.monitor_pages[0]) {
+				ret = -ENOMEM;
+				goto cleanup;
+			}
+
+			vmbus_connection.monitor_pages[1]
+				= memremap(vmbus_connection.monitor_pages_pa[1],
+					   HV_HYP_PAGE_SIZE,
+					   MEMREMAP_WB);
+			if (!vmbus_connection.monitor_pages[1]) {
+				ret = -ENOMEM;
+				goto cleanup;
+			}
+		}
+
+		/*
+		 * Set memory host visibility hvcall smears memory
+		 * and so zero monitor pages here.
+		 */
+		memset(vmbus_connection.monitor_pages[0], 0x00,
+		       HV_HYP_PAGE_SIZE);
+		memset(vmbus_connection.monitor_pages[1], 0x00,
+		       HV_HYP_PAGE_SIZE);
+
+	}
+
+	msginfo = kzalloc(sizeof(*msginfo) +
+			  sizeof(struct vmbus_channel_initiate_contact),
+			  GFP_KERNEL);
+	if (msginfo == NULL) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	/*
+	 * Negotiate a compatible VMBUS version number with the
+	 * host. We start with the highest number we can support
+	 * and work our way down until we negotiate a compatible
+	 * version.
+	 */
+
+	for (i = 0; ; i++) {
+		if (i == ARRAY_SIZE(vmbus_versions)) {
+			ret = -EDOM;
+			goto cleanup;
+		}
+
+		version = vmbus_versions[i];
+		if (version > max_version)
+			continue;
+
+		ret = vmbus_negotiate_version(msginfo, version);
+		if (ret == -ETIMEDOUT)
+			goto cleanup;
+
+		if (vmbus_connection.conn_state == CONNECTED)
+			break;
+	}
+
+	if (hv_is_isolation_supported() && version < VERSION_WIN10_V5_2) {
+		pr_err("Invalid VMBus version %d.%d (expected >= %d.%d) from the host supporting isolation\n",
+		       version >> 16, version & 0xFFFF, VERSION_WIN10_V5_2 >> 16, VERSION_WIN10_V5_2 & 0xFFFF);
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	vmbus_proto_version = version;
+	pr_info("Vmbus version:%d.%d\n",
+		version >> 16, version & 0xFFFF);
+
+	vmbus_connection.channels = kcalloc(MAX_CHANNEL_RELIDS,
+					    sizeof(struct vmbus_channel *),
+					    GFP_KERNEL);
+	if (vmbus_connection.channels == NULL) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	kfree(msginfo);
+	return 0;
+
+cleanup:
+	pr_err("Unable to connect to host\n");
+
+	vmbus_connection.conn_state = DISCONNECTED;
+	vmbus_disconnect();
+
+	kfree(msginfo);
+
+	return ret;
+}
+
+void vmbus_disconnect(void)
+{
+	/*
+	 * First send the unload request to the host.
+	 */
+	vmbus_initiate_unload(false);
+
+	if (vmbus_connection.handle_sub_chan_wq)
+		destroy_workqueue(vmbus_connection.handle_sub_chan_wq);
+
+	if (vmbus_connection.handle_primary_chan_wq)
+		destroy_workqueue(vmbus_connection.handle_primary_chan_wq);
+
+	if (vmbus_connection.rescind_work_queue)
+		destroy_workqueue(vmbus_connection.rescind_work_queue);
+
+	if (vmbus_connection.work_queue)
+		destroy_workqueue(vmbus_connection.work_queue);
+
+	if (vmbus_connection.int_page) {
+		hv_free_hyperv_page((unsigned long)vmbus_connection.int_page);
+		vmbus_connection.int_page = NULL;
+	}
+
+	if (hv_is_isolation_supported()) {
+		/*
+		 * memunmap() checks input address is ioremap address or not
+		 * inside. It doesn't unmap any thing in the non-SNP CVM and
+		 * so not check CVM type here.
+		 */
+		memunmap(vmbus_connection.monitor_pages[0]);
+		memunmap(vmbus_connection.monitor_pages[1]);
+
+		set_memory_encrypted((unsigned long)
+			vmbus_connection.monitor_pages_original[0],
+			1);
+		set_memory_encrypted((unsigned long)
+			vmbus_connection.monitor_pages_original[1],
+			1);
+	}
+
+	hv_free_hyperv_page((unsigned long)
+		vmbus_connection.monitor_pages_original[0]);
+	hv_free_hyperv_page((unsigned long)
+		vmbus_connection.monitor_pages_original[1]);
+	vmbus_connection.monitor_pages_original[0] =
+		vmbus_connection.monitor_pages[0] = NULL;
+	vmbus_connection.monitor_pages_original[1] =
+		vmbus_connection.monitor_pages[1] = NULL;
+}
+
+/*
+ * relid2channel - Get the channel object given its
+ * child relative id (ie channel id)
+ */
+struct vmbus_channel *relid2channel(u32 relid)
+{
+	if (vmbus_connection.channels == NULL) {
+		pr_warn_once("relid2channel: relid=%d: No channels mapped!\n", relid);
+		return NULL;
+	}
+	if (WARN_ON(relid >= MAX_CHANNEL_RELIDS))
+		return NULL;
+	return READ_ONCE(vmbus_connection.channels[relid]);
+}
+
+/*
+ * vmbus_on_event - Process a channel event notification
+ *
+ * For batched channels (default) optimize host to guest signaling
+ * by ensuring:
+ * 1. While reading the channel, we disable interrupts from host.
+ * 2. Ensure that we process all posted messages from the host
+ *    before returning from this callback.
+ * 3. Once we return, enable signaling from the host. Once this
+ *    state is set we check to see if additional packets are
+ *    available to read. In this case we repeat the process.
+ *    If this tasklet has been running for a long time
+ *    then reschedule ourselves.
+ */
+void vmbus_on_event(unsigned long data)
+{
+	struct vmbus_channel *channel = (void *) data;
+	void (*callback_fn)(void *context);
+
+	trace_vmbus_on_event(channel);
+
+	hv_debug_delay_test(channel, INTERRUPT_DELAY);
+
+	/* A channel once created is persistent even when
+	 * there is no driver handling the device. An
+	 * unloading driver sets the onchannel_callback to NULL.
+	 */
+	callback_fn = READ_ONCE(channel->onchannel_callback);
+	if (unlikely(!callback_fn))
+		return;
+
+	(*callback_fn)(channel->channel_callback_context);
+
+	if (channel->callback_mode != HV_CALL_BATCHED)
+		return;
+
+	if (likely(hv_end_read(&channel->inbound) == 0))
+		return;
+
+	hv_begin_read(&channel->inbound);
+	tasklet_schedule(&channel->callback_event);
+}
+
+/*
+ * vmbus_post_msg - Send a msg on the vmbus's message connection
+ */
+int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep)
+{
+	struct vmbus_channel_message_header *hdr;
+	union hv_connection_id conn_id;
+	int ret = 0;
+	int retries = 0;
+	u32 usec = 1;
+
+	conn_id.asu32 = 0;
+	conn_id.u.id = vmbus_connection.msg_conn_id;
+
+	/*
+	 * hv_post_message() can have transient failures because of
+	 * insufficient resources. Retry the operation a couple of
+	 * times before giving up.
+	 */
+	while (retries < 100) {
+		ret = hv_post_message(conn_id, 1, buffer, buflen);
+
+		switch (ret) {
+		case HV_STATUS_INVALID_CONNECTION_ID:
+			/*
+			 * See vmbus_negotiate_version(): VMBus protocol 5.0
+			 * and higher require that we must use
+			 * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate
+			 * Contact message, but on old hosts that only
+			 * support VMBus protocol 4.0 or lower, here we get
+			 * HV_STATUS_INVALID_CONNECTION_ID and we should
+			 * return an error immediately without retrying.
+			 */
+			hdr = buffer;
+			if (hdr->msgtype == CHANNELMSG_INITIATE_CONTACT)
+				return -EINVAL;
+			/*
+			 * We could get this if we send messages too
+			 * frequently.
+			 */
+			ret = -EAGAIN;
+			break;
+		case HV_STATUS_INSUFFICIENT_MEMORY:
+		case HV_STATUS_INSUFFICIENT_BUFFERS:
+			ret = -ENOBUFS;
+			break;
+		case HV_STATUS_SUCCESS:
+			return ret;
+		default:
+			pr_err("hv_post_msg() failed; error code:%d\n", ret);
+			return -EINVAL;
+		}
+
+		retries++;
+		if (can_sleep && usec > 1000)
+			msleep(usec / 1000);
+		else if (usec < MAX_UDELAY_MS * 1000)
+			udelay(usec);
+		else
+			mdelay(usec / 1000);
+
+		if (retries < 22)
+			usec *= 2;
+	}
+	return ret;
+}
+
+/*
+ * vmbus_set_event - Send an event notification to the parent
+ */
+void vmbus_set_event(struct vmbus_channel *channel)
+{
+	u32 child_relid = channel->offermsg.child_relid;
+
+	if (!channel->is_dedicated_interrupt)
+		vmbus_send_interrupt(child_relid);
+
+	++channel->sig_events;
+
+	if (hv_isolation_type_snp())
+		hv_ghcb_hypercall(HVCALL_SIGNAL_EVENT, &channel->sig_event,
+				NULL, sizeof(channel->sig_event));
+	else
+		hv_do_fast_hypercall8(HVCALL_SIGNAL_EVENT, channel->sig_event);
+}
+EXPORT_SYMBOL_GPL(vmbus_set_event);