From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/hv/connection.c | 549 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 549 insertions(+) create mode 100644 drivers/hv/connection.c (limited to 'drivers/hv/connection.c') 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 + * Hank Janssen + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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); -- cgit v1.2.3