540 lines
14 KiB
C
540 lines
14 KiB
C
|
// 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.
|
||
|
*/
|
||
|
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,
|
||
|
VERSION_WIN7,
|
||
|
VERSION_WS2008
|
||
|
};
|
||
|
|
||
|
/*
|
||
|
* 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.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.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 (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;
|
||
|
unsigned long time_limit = jiffies + 2;
|
||
|
|
||
|
trace_vmbus_on_event(channel);
|
||
|
|
||
|
hv_debug_delay_test(channel, INTERRUPT_DELAY);
|
||
|
do {
|
||
|
void (*callback_fn)(void *);
|
||
|
|
||
|
/* 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 == NULL))
|
||
|
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);
|
||
|
} while (likely(time_before(jiffies, time_limit)));
|
||
|
|
||
|
/* The time limit (2 jiffies) has been reached */
|
||
|
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);
|