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![Michael Kelley](/assets/img/avatar_default.png)
vmbus_wait_for_unload() may be called in the panic path after other
CPUs are stopped. vmbus_wait_for_unload() currently loops through
online CPUs looking for the UNLOAD response message. But the values of
CONFIG_KEXEC_CORE and crash_kexec_post_notifiers affect the path used
to stop the other CPUs, and in one of the paths the stopped CPUs
are removed from cpu_online_mask. This removal happens in both
x86/x64 and arm64 architectures. In such a case, vmbus_wait_for_unload()
only checks the panic'ing CPU, and misses the UNLOAD response message
except when the panic'ing CPU is CPU 0. vmbus_wait_for_unload()
eventually times out, but only after waiting 100 seconds.
Fix this by looping through *present* CPUs in vmbus_wait_for_unload().
The cpu_present_mask is not modified by stopping the other CPUs in the
panic path, nor should it be.
Also, in a CoCo VM the synic_message_page is not allocated in
hv_synic_alloc(), but is set and cleared in hv_synic_enable_regs()
and hv_synic_disable_regs() such that it is set only when the CPU is
online. If not all present CPUs are online when vmbus_wait_for_unload()
is called, the synic_message_page might be NULL. Add a check for this.
Fixes: cd95aad557
("Drivers: hv: vmbus: handle various crash scenarios")
Cc: stable@vger.kernel.org
Reported-by: John Starks <jostarks@microsoft.com>
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/1684422832-38476-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
1619 lines
45 KiB
C
1619 lines
45 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (c) 2009, Microsoft Corporation.
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*
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* Authors:
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* Haiyang Zhang <haiyangz@microsoft.com>
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* Hank Janssen <hjanssen@microsoft.com>
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/kernel.h>
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#include <linux/interrupt.h>
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#include <linux/sched.h>
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#include <linux/wait.h>
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#include <linux/mm.h>
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#include <linux/slab.h>
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#include <linux/list.h>
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#include <linux/module.h>
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#include <linux/completion.h>
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#include <linux/delay.h>
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#include <linux/cpu.h>
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#include <linux/hyperv.h>
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#include <asm/mshyperv.h>
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#include <linux/sched/isolation.h>
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#include "hyperv_vmbus.h"
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static void init_vp_index(struct vmbus_channel *channel);
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const struct vmbus_device vmbus_devs[] = {
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/* IDE */
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{ .dev_type = HV_IDE,
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HV_IDE_GUID,
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.perf_device = true,
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.allowed_in_isolated = false,
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},
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/* SCSI */
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{ .dev_type = HV_SCSI,
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HV_SCSI_GUID,
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.perf_device = true,
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.allowed_in_isolated = true,
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},
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/* Fibre Channel */
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{ .dev_type = HV_FC,
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HV_SYNTHFC_GUID,
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.perf_device = true,
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.allowed_in_isolated = false,
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},
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/* Synthetic NIC */
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{ .dev_type = HV_NIC,
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HV_NIC_GUID,
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.perf_device = true,
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.allowed_in_isolated = true,
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},
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/* Network Direct */
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{ .dev_type = HV_ND,
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HV_ND_GUID,
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.perf_device = true,
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.allowed_in_isolated = false,
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},
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/* PCIE */
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{ .dev_type = HV_PCIE,
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HV_PCIE_GUID,
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.perf_device = false,
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.allowed_in_isolated = true,
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},
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/* Synthetic Frame Buffer */
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{ .dev_type = HV_FB,
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HV_SYNTHVID_GUID,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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/* Synthetic Keyboard */
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{ .dev_type = HV_KBD,
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HV_KBD_GUID,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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/* Synthetic MOUSE */
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{ .dev_type = HV_MOUSE,
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HV_MOUSE_GUID,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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/* KVP */
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{ .dev_type = HV_KVP,
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HV_KVP_GUID,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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/* Time Synch */
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{ .dev_type = HV_TS,
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HV_TS_GUID,
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.perf_device = false,
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.allowed_in_isolated = true,
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},
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/* Heartbeat */
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{ .dev_type = HV_HB,
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HV_HEART_BEAT_GUID,
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.perf_device = false,
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.allowed_in_isolated = true,
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},
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/* Shutdown */
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{ .dev_type = HV_SHUTDOWN,
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HV_SHUTDOWN_GUID,
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.perf_device = false,
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.allowed_in_isolated = true,
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},
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/* File copy */
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{ .dev_type = HV_FCOPY,
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HV_FCOPY_GUID,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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/* Backup */
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{ .dev_type = HV_BACKUP,
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HV_VSS_GUID,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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/* Dynamic Memory */
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{ .dev_type = HV_DM,
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HV_DM_GUID,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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/* Unknown GUID */
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{ .dev_type = HV_UNKNOWN,
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.perf_device = false,
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.allowed_in_isolated = false,
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},
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};
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static const struct {
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guid_t guid;
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} vmbus_unsupported_devs[] = {
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{ HV_AVMA1_GUID },
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{ HV_AVMA2_GUID },
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{ HV_RDV_GUID },
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{ HV_IMC_GUID },
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};
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/*
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* The rescinded channel may be blocked waiting for a response from the host;
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* take care of that.
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*/
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static void vmbus_rescind_cleanup(struct vmbus_channel *channel)
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{
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struct vmbus_channel_msginfo *msginfo;
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unsigned long flags;
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spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
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channel->rescind = true;
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list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
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msglistentry) {
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if (msginfo->waiting_channel == channel) {
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complete(&msginfo->waitevent);
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break;
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}
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}
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spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
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}
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static bool is_unsupported_vmbus_devs(const guid_t *guid)
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{
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int i;
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for (i = 0; i < ARRAY_SIZE(vmbus_unsupported_devs); i++)
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if (guid_equal(guid, &vmbus_unsupported_devs[i].guid))
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return true;
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return false;
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}
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static u16 hv_get_dev_type(const struct vmbus_channel *channel)
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{
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const guid_t *guid = &channel->offermsg.offer.if_type;
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u16 i;
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if (is_hvsock_channel(channel) || is_unsupported_vmbus_devs(guid))
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return HV_UNKNOWN;
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for (i = HV_IDE; i < HV_UNKNOWN; i++) {
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if (guid_equal(guid, &vmbus_devs[i].guid))
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return i;
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}
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pr_info("Unknown GUID: %pUl\n", guid);
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return i;
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}
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/**
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* vmbus_prep_negotiate_resp() - Create default response for Negotiate message
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* @icmsghdrp: Pointer to msg header structure
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* @buf: Raw buffer channel data
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* @buflen: Length of the raw buffer channel data.
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* @fw_version: The framework versions we can support.
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* @fw_vercnt: The size of @fw_version.
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* @srv_version: The service versions we can support.
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* @srv_vercnt: The size of @srv_version.
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* @nego_fw_version: The selected framework version.
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* @nego_srv_version: The selected service version.
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*
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* Note: Versions are given in decreasing order.
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*
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* Set up and fill in default negotiate response message.
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* Mainly used by Hyper-V drivers.
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*/
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bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, u8 *buf,
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u32 buflen, const int *fw_version, int fw_vercnt,
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const int *srv_version, int srv_vercnt,
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int *nego_fw_version, int *nego_srv_version)
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{
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int icframe_major, icframe_minor;
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int icmsg_major, icmsg_minor;
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int fw_major, fw_minor;
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int srv_major, srv_minor;
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int i, j;
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bool found_match = false;
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struct icmsg_negotiate *negop;
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/* Check that there's enough space for icframe_vercnt, icmsg_vercnt */
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if (buflen < ICMSG_HDR + offsetof(struct icmsg_negotiate, reserved)) {
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pr_err_ratelimited("Invalid icmsg negotiate\n");
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return false;
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}
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icmsghdrp->icmsgsize = 0x10;
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negop = (struct icmsg_negotiate *)&buf[ICMSG_HDR];
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icframe_major = negop->icframe_vercnt;
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icframe_minor = 0;
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icmsg_major = negop->icmsg_vercnt;
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icmsg_minor = 0;
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/* Validate negop packet */
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if (icframe_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT ||
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icmsg_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT ||
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ICMSG_NEGOTIATE_PKT_SIZE(icframe_major, icmsg_major) > buflen) {
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pr_err_ratelimited("Invalid icmsg negotiate - icframe_major: %u, icmsg_major: %u\n",
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icframe_major, icmsg_major);
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goto fw_error;
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}
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/*
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* Select the framework version number we will
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* support.
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*/
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for (i = 0; i < fw_vercnt; i++) {
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fw_major = (fw_version[i] >> 16);
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fw_minor = (fw_version[i] & 0xFFFF);
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for (j = 0; j < negop->icframe_vercnt; j++) {
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if ((negop->icversion_data[j].major == fw_major) &&
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(negop->icversion_data[j].minor == fw_minor)) {
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icframe_major = negop->icversion_data[j].major;
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icframe_minor = negop->icversion_data[j].minor;
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found_match = true;
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break;
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}
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}
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if (found_match)
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break;
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}
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if (!found_match)
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goto fw_error;
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found_match = false;
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for (i = 0; i < srv_vercnt; i++) {
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srv_major = (srv_version[i] >> 16);
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srv_minor = (srv_version[i] & 0xFFFF);
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for (j = negop->icframe_vercnt;
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(j < negop->icframe_vercnt + negop->icmsg_vercnt);
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j++) {
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if ((negop->icversion_data[j].major == srv_major) &&
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(negop->icversion_data[j].minor == srv_minor)) {
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icmsg_major = negop->icversion_data[j].major;
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icmsg_minor = negop->icversion_data[j].minor;
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found_match = true;
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break;
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}
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}
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if (found_match)
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break;
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}
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/*
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* Respond with the framework and service
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* version numbers we can support.
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*/
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fw_error:
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if (!found_match) {
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negop->icframe_vercnt = 0;
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negop->icmsg_vercnt = 0;
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} else {
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negop->icframe_vercnt = 1;
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negop->icmsg_vercnt = 1;
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}
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if (nego_fw_version)
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*nego_fw_version = (icframe_major << 16) | icframe_minor;
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if (nego_srv_version)
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*nego_srv_version = (icmsg_major << 16) | icmsg_minor;
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negop->icversion_data[0].major = icframe_major;
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negop->icversion_data[0].minor = icframe_minor;
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negop->icversion_data[1].major = icmsg_major;
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negop->icversion_data[1].minor = icmsg_minor;
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return found_match;
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}
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EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
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/*
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* alloc_channel - Allocate and initialize a vmbus channel object
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*/
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static struct vmbus_channel *alloc_channel(void)
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{
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struct vmbus_channel *channel;
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channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
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if (!channel)
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return NULL;
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spin_lock_init(&channel->sched_lock);
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init_completion(&channel->rescind_event);
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INIT_LIST_HEAD(&channel->sc_list);
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tasklet_init(&channel->callback_event,
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vmbus_on_event, (unsigned long)channel);
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hv_ringbuffer_pre_init(channel);
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return channel;
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}
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/*
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* free_channel - Release the resources used by the vmbus channel object
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*/
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static void free_channel(struct vmbus_channel *channel)
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{
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tasklet_kill(&channel->callback_event);
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vmbus_remove_channel_attr_group(channel);
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kobject_put(&channel->kobj);
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}
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void vmbus_channel_map_relid(struct vmbus_channel *channel)
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{
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if (WARN_ON(channel->offermsg.child_relid >= MAX_CHANNEL_RELIDS))
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return;
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/*
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* The mapping of the channel's relid is visible from the CPUs that
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* execute vmbus_chan_sched() by the time that vmbus_chan_sched() will
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* execute:
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*
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* (a) In the "normal (i.e., not resuming from hibernation)" path,
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* the full barrier in virt_store_mb() guarantees that the store
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* is propagated to all CPUs before the add_channel_work work
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* is queued. In turn, add_channel_work is queued before the
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* channel's ring buffer is allocated/initialized and the
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* OPENCHANNEL message for the channel is sent in vmbus_open().
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* Hyper-V won't start sending the interrupts for the channel
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* before the OPENCHANNEL message is acked. The memory barrier
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* in vmbus_chan_sched() -> sync_test_and_clear_bit() ensures
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* that vmbus_chan_sched() must find the channel's relid in
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* recv_int_page before retrieving the channel pointer from the
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* array of channels.
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*
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* (b) In the "resuming from hibernation" path, the virt_store_mb()
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* guarantees that the store is propagated to all CPUs before
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* the VMBus connection is marked as ready for the resume event
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* (cf. check_ready_for_resume_event()). The interrupt handler
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* of the VMBus driver and vmbus_chan_sched() can not run before
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* vmbus_bus_resume() has completed execution (cf. resume_noirq).
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*/
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virt_store_mb(
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vmbus_connection.channels[channel->offermsg.child_relid],
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channel);
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}
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void vmbus_channel_unmap_relid(struct vmbus_channel *channel)
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{
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if (WARN_ON(channel->offermsg.child_relid >= MAX_CHANNEL_RELIDS))
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return;
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WRITE_ONCE(
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vmbus_connection.channels[channel->offermsg.child_relid],
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NULL);
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}
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static void vmbus_release_relid(u32 relid)
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{
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struct vmbus_channel_relid_released msg;
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int ret;
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memset(&msg, 0, sizeof(struct vmbus_channel_relid_released));
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msg.child_relid = relid;
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msg.header.msgtype = CHANNELMSG_RELID_RELEASED;
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ret = vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released),
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true);
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trace_vmbus_release_relid(&msg, ret);
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}
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void hv_process_channel_removal(struct vmbus_channel *channel)
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{
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lockdep_assert_held(&vmbus_connection.channel_mutex);
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BUG_ON(!channel->rescind);
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/*
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* hv_process_channel_removal() could find INVALID_RELID only for
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* hv_sock channels. See the inline comments in vmbus_onoffer().
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*/
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WARN_ON(channel->offermsg.child_relid == INVALID_RELID &&
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!is_hvsock_channel(channel));
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|
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/*
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* Upon suspend, an in-use hv_sock channel is removed from the array of
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* channels and the relid is invalidated. After hibernation, when the
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* user-space application destroys the channel, it's unnecessary and
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* unsafe to remove the channel from the array of channels. See also
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* the inline comments before the call of vmbus_release_relid() below.
|
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*/
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if (channel->offermsg.child_relid != INVALID_RELID)
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vmbus_channel_unmap_relid(channel);
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|
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if (channel->primary_channel == NULL)
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list_del(&channel->listentry);
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else
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list_del(&channel->sc_list);
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|
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/*
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* If this is a "perf" channel, updates the hv_numa_map[] masks so that
|
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* init_vp_index() can (re-)use the CPU.
|
|
*/
|
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if (hv_is_perf_channel(channel))
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hv_clear_allocated_cpu(channel->target_cpu);
|
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|
|
/*
|
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* Upon suspend, an in-use hv_sock channel is marked as "rescinded" and
|
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* the relid is invalidated; after hibernation, when the user-space app
|
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* destroys the channel, the relid is INVALID_RELID, and in this case
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* it's unnecessary and unsafe to release the old relid, since the same
|
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* relid can refer to a completely different channel now.
|
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*/
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if (channel->offermsg.child_relid != INVALID_RELID)
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vmbus_release_relid(channel->offermsg.child_relid);
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|
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free_channel(channel);
|
|
}
|
|
|
|
void vmbus_free_channels(void)
|
|
{
|
|
struct vmbus_channel *channel, *tmp;
|
|
|
|
list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list,
|
|
listentry) {
|
|
/* hv_process_channel_removal() needs this */
|
|
channel->rescind = true;
|
|
|
|
vmbus_device_unregister(channel->device_obj);
|
|
}
|
|
}
|
|
|
|
/* Note: the function can run concurrently for primary/sub channels. */
|
|
static void vmbus_add_channel_work(struct work_struct *work)
|
|
{
|
|
struct vmbus_channel *newchannel =
|
|
container_of(work, struct vmbus_channel, add_channel_work);
|
|
struct vmbus_channel *primary_channel = newchannel->primary_channel;
|
|
int ret;
|
|
|
|
/*
|
|
* This state is used to indicate a successful open
|
|
* so that when we do close the channel normally, we
|
|
* can cleanup properly.
|
|
*/
|
|
newchannel->state = CHANNEL_OPEN_STATE;
|
|
|
|
if (primary_channel != NULL) {
|
|
/* newchannel is a sub-channel. */
|
|
struct hv_device *dev = primary_channel->device_obj;
|
|
|
|
if (vmbus_add_channel_kobj(dev, newchannel))
|
|
goto err_deq_chan;
|
|
|
|
if (primary_channel->sc_creation_callback != NULL)
|
|
primary_channel->sc_creation_callback(newchannel);
|
|
|
|
newchannel->probe_done = true;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Start the process of binding the primary channel to the driver
|
|
*/
|
|
newchannel->device_obj = vmbus_device_create(
|
|
&newchannel->offermsg.offer.if_type,
|
|
&newchannel->offermsg.offer.if_instance,
|
|
newchannel);
|
|
if (!newchannel->device_obj)
|
|
goto err_deq_chan;
|
|
|
|
newchannel->device_obj->device_id = newchannel->device_id;
|
|
/*
|
|
* Add the new device to the bus. This will kick off device-driver
|
|
* binding which eventually invokes the device driver's AddDevice()
|
|
* method.
|
|
*
|
|
* If vmbus_device_register() fails, the 'device_obj' is freed in
|
|
* vmbus_device_release() as called by device_unregister() in the
|
|
* error path of vmbus_device_register(). In the outside error
|
|
* path, there's no need to free it.
|
|
*/
|
|
ret = vmbus_device_register(newchannel->device_obj);
|
|
|
|
if (ret != 0) {
|
|
pr_err("unable to add child device object (relid %d)\n",
|
|
newchannel->offermsg.child_relid);
|
|
goto err_deq_chan;
|
|
}
|
|
|
|
newchannel->probe_done = true;
|
|
return;
|
|
|
|
err_deq_chan:
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
|
|
/*
|
|
* We need to set the flag, otherwise
|
|
* vmbus_onoffer_rescind() can be blocked.
|
|
*/
|
|
newchannel->probe_done = true;
|
|
|
|
if (primary_channel == NULL)
|
|
list_del(&newchannel->listentry);
|
|
else
|
|
list_del(&newchannel->sc_list);
|
|
|
|
/* vmbus_process_offer() has mapped the channel. */
|
|
vmbus_channel_unmap_relid(newchannel);
|
|
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
|
|
vmbus_release_relid(newchannel->offermsg.child_relid);
|
|
|
|
free_channel(newchannel);
|
|
}
|
|
|
|
/*
|
|
* vmbus_process_offer - Process the offer by creating a channel/device
|
|
* associated with this offer
|
|
*/
|
|
static void vmbus_process_offer(struct vmbus_channel *newchannel)
|
|
{
|
|
struct vmbus_channel *channel;
|
|
struct workqueue_struct *wq;
|
|
bool fnew = true;
|
|
|
|
/*
|
|
* Synchronize vmbus_process_offer() and CPU hotplugging:
|
|
*
|
|
* CPU1 CPU2
|
|
*
|
|
* [vmbus_process_offer()] [Hot removal of the CPU]
|
|
*
|
|
* CPU_READ_LOCK CPUS_WRITE_LOCK
|
|
* LOAD cpu_online_mask SEARCH chn_list
|
|
* STORE target_cpu LOAD target_cpu
|
|
* INSERT chn_list STORE cpu_online_mask
|
|
* CPUS_READ_UNLOCK CPUS_WRITE_UNLOCK
|
|
*
|
|
* Forbids: CPU1's LOAD from *not* seing CPU2's STORE &&
|
|
* CPU2's SEARCH from *not* seeing CPU1's INSERT
|
|
*
|
|
* Forbids: CPU2's SEARCH from seeing CPU1's INSERT &&
|
|
* CPU2's LOAD from *not* seing CPU1's STORE
|
|
*/
|
|
cpus_read_lock();
|
|
|
|
/*
|
|
* Serializes the modifications of the chn_list list as well as
|
|
* the accesses to next_numa_node_id in init_vp_index().
|
|
*/
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
|
|
list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
|
|
if (guid_equal(&channel->offermsg.offer.if_type,
|
|
&newchannel->offermsg.offer.if_type) &&
|
|
guid_equal(&channel->offermsg.offer.if_instance,
|
|
&newchannel->offermsg.offer.if_instance)) {
|
|
fnew = false;
|
|
newchannel->primary_channel = channel;
|
|
break;
|
|
}
|
|
}
|
|
|
|
init_vp_index(newchannel);
|
|
|
|
/* Remember the channels that should be cleaned up upon suspend. */
|
|
if (is_hvsock_channel(newchannel) || is_sub_channel(newchannel))
|
|
atomic_inc(&vmbus_connection.nr_chan_close_on_suspend);
|
|
|
|
/*
|
|
* Now that we have acquired the channel_mutex,
|
|
* we can release the potentially racing rescind thread.
|
|
*/
|
|
atomic_dec(&vmbus_connection.offer_in_progress);
|
|
|
|
if (fnew) {
|
|
list_add_tail(&newchannel->listentry,
|
|
&vmbus_connection.chn_list);
|
|
} else {
|
|
/*
|
|
* Check to see if this is a valid sub-channel.
|
|
*/
|
|
if (newchannel->offermsg.offer.sub_channel_index == 0) {
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
cpus_read_unlock();
|
|
/*
|
|
* Don't call free_channel(), because newchannel->kobj
|
|
* is not initialized yet.
|
|
*/
|
|
kfree(newchannel);
|
|
WARN_ON_ONCE(1);
|
|
return;
|
|
}
|
|
/*
|
|
* Process the sub-channel.
|
|
*/
|
|
list_add_tail(&newchannel->sc_list, &channel->sc_list);
|
|
}
|
|
|
|
vmbus_channel_map_relid(newchannel);
|
|
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
cpus_read_unlock();
|
|
|
|
/*
|
|
* vmbus_process_offer() mustn't call channel->sc_creation_callback()
|
|
* directly for sub-channels, because sc_creation_callback() ->
|
|
* vmbus_open() may never get the host's response to the
|
|
* OPEN_CHANNEL message (the host may rescind a channel at any time,
|
|
* e.g. in the case of hot removing a NIC), and vmbus_onoffer_rescind()
|
|
* may not wake up the vmbus_open() as it's blocked due to a non-zero
|
|
* vmbus_connection.offer_in_progress, and finally we have a deadlock.
|
|
*
|
|
* The above is also true for primary channels, if the related device
|
|
* drivers use sync probing mode by default.
|
|
*
|
|
* And, usually the handling of primary channels and sub-channels can
|
|
* depend on each other, so we should offload them to different
|
|
* workqueues to avoid possible deadlock, e.g. in sync-probing mode,
|
|
* NIC1's netvsc_subchan_work() can race with NIC2's netvsc_probe() ->
|
|
* rtnl_lock(), and causes deadlock: the former gets the rtnl_lock
|
|
* and waits for all the sub-channels to appear, but the latter
|
|
* can't get the rtnl_lock and this blocks the handling of
|
|
* sub-channels.
|
|
*/
|
|
INIT_WORK(&newchannel->add_channel_work, vmbus_add_channel_work);
|
|
wq = fnew ? vmbus_connection.handle_primary_chan_wq :
|
|
vmbus_connection.handle_sub_chan_wq;
|
|
queue_work(wq, &newchannel->add_channel_work);
|
|
}
|
|
|
|
/*
|
|
* Check if CPUs used by other channels of the same device.
|
|
* It should only be called by init_vp_index().
|
|
*/
|
|
static bool hv_cpuself_used(u32 cpu, struct vmbus_channel *chn)
|
|
{
|
|
struct vmbus_channel *primary = chn->primary_channel;
|
|
struct vmbus_channel *sc;
|
|
|
|
lockdep_assert_held(&vmbus_connection.channel_mutex);
|
|
|
|
if (!primary)
|
|
return false;
|
|
|
|
if (primary->target_cpu == cpu)
|
|
return true;
|
|
|
|
list_for_each_entry(sc, &primary->sc_list, sc_list)
|
|
if (sc != chn && sc->target_cpu == cpu)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* We use this state to statically distribute the channel interrupt load.
|
|
*/
|
|
static int next_numa_node_id;
|
|
|
|
/*
|
|
* We can statically distribute the incoming channel interrupt load
|
|
* by binding a channel to VCPU.
|
|
*
|
|
* For non-performance critical channels we assign the VMBUS_CONNECT_CPU.
|
|
* Performance critical channels will be distributed evenly among all
|
|
* the available NUMA nodes. Once the node is assigned, we will assign
|
|
* the CPU based on a simple round robin scheme.
|
|
*/
|
|
static void init_vp_index(struct vmbus_channel *channel)
|
|
{
|
|
bool perf_chn = hv_is_perf_channel(channel);
|
|
u32 i, ncpu = num_online_cpus();
|
|
cpumask_var_t available_mask;
|
|
struct cpumask *allocated_mask;
|
|
const struct cpumask *hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
|
|
u32 target_cpu;
|
|
int numa_node;
|
|
|
|
if (!perf_chn ||
|
|
!alloc_cpumask_var(&available_mask, GFP_KERNEL) ||
|
|
cpumask_empty(hk_mask)) {
|
|
/*
|
|
* If the channel is not a performance critical
|
|
* channel, bind it to VMBUS_CONNECT_CPU.
|
|
* In case alloc_cpumask_var() fails, bind it to
|
|
* VMBUS_CONNECT_CPU.
|
|
* If all the cpus are isolated, bind it to
|
|
* VMBUS_CONNECT_CPU.
|
|
*/
|
|
channel->target_cpu = VMBUS_CONNECT_CPU;
|
|
if (perf_chn)
|
|
hv_set_allocated_cpu(VMBUS_CONNECT_CPU);
|
|
return;
|
|
}
|
|
|
|
for (i = 1; i <= ncpu + 1; i++) {
|
|
while (true) {
|
|
numa_node = next_numa_node_id++;
|
|
if (numa_node == nr_node_ids) {
|
|
next_numa_node_id = 0;
|
|
continue;
|
|
}
|
|
if (cpumask_empty(cpumask_of_node(numa_node)))
|
|
continue;
|
|
break;
|
|
}
|
|
allocated_mask = &hv_context.hv_numa_map[numa_node];
|
|
|
|
retry:
|
|
cpumask_xor(available_mask, allocated_mask, cpumask_of_node(numa_node));
|
|
cpumask_and(available_mask, available_mask, hk_mask);
|
|
|
|
if (cpumask_empty(available_mask)) {
|
|
/*
|
|
* We have cycled through all the CPUs in the node;
|
|
* reset the allocated map.
|
|
*/
|
|
cpumask_clear(allocated_mask);
|
|
goto retry;
|
|
}
|
|
|
|
target_cpu = cpumask_first(available_mask);
|
|
cpumask_set_cpu(target_cpu, allocated_mask);
|
|
|
|
if (channel->offermsg.offer.sub_channel_index >= ncpu ||
|
|
i > ncpu || !hv_cpuself_used(target_cpu, channel))
|
|
break;
|
|
}
|
|
|
|
channel->target_cpu = target_cpu;
|
|
|
|
free_cpumask_var(available_mask);
|
|
}
|
|
|
|
#define UNLOAD_DELAY_UNIT_MS 10 /* 10 milliseconds */
|
|
#define UNLOAD_WAIT_MS (100*1000) /* 100 seconds */
|
|
#define UNLOAD_WAIT_LOOPS (UNLOAD_WAIT_MS/UNLOAD_DELAY_UNIT_MS)
|
|
#define UNLOAD_MSG_MS (5*1000) /* Every 5 seconds */
|
|
#define UNLOAD_MSG_LOOPS (UNLOAD_MSG_MS/UNLOAD_DELAY_UNIT_MS)
|
|
|
|
static void vmbus_wait_for_unload(void)
|
|
{
|
|
int cpu;
|
|
void *page_addr;
|
|
struct hv_message *msg;
|
|
struct vmbus_channel_message_header *hdr;
|
|
u32 message_type, i;
|
|
|
|
/*
|
|
* CHANNELMSG_UNLOAD_RESPONSE is always delivered to the CPU which was
|
|
* used for initial contact or to CPU0 depending on host version. When
|
|
* we're crashing on a different CPU let's hope that IRQ handler on
|
|
* the cpu which receives CHANNELMSG_UNLOAD_RESPONSE is still
|
|
* functional and vmbus_unload_response() will complete
|
|
* vmbus_connection.unload_event. If not, the last thing we can do is
|
|
* read message pages for all CPUs directly.
|
|
*
|
|
* Wait up to 100 seconds since an Azure host must writeback any dirty
|
|
* data in its disk cache before the VMbus UNLOAD request will
|
|
* complete. This flushing has been empirically observed to take up
|
|
* to 50 seconds in cases with a lot of dirty data, so allow additional
|
|
* leeway and for inaccuracies in mdelay(). But eventually time out so
|
|
* that the panic path can't get hung forever in case the response
|
|
* message isn't seen.
|
|
*/
|
|
for (i = 1; i <= UNLOAD_WAIT_LOOPS; i++) {
|
|
if (completion_done(&vmbus_connection.unload_event))
|
|
goto completed;
|
|
|
|
for_each_present_cpu(cpu) {
|
|
struct hv_per_cpu_context *hv_cpu
|
|
= per_cpu_ptr(hv_context.cpu_context, cpu);
|
|
|
|
/*
|
|
* In a CoCo VM the synic_message_page is not allocated
|
|
* in hv_synic_alloc(). Instead it is set/cleared in
|
|
* hv_synic_enable_regs() and hv_synic_disable_regs()
|
|
* such that it is set only when the CPU is online. If
|
|
* not all present CPUs are online, the message page
|
|
* might be NULL, so skip such CPUs.
|
|
*/
|
|
page_addr = hv_cpu->synic_message_page;
|
|
if (!page_addr)
|
|
continue;
|
|
|
|
msg = (struct hv_message *)page_addr
|
|
+ VMBUS_MESSAGE_SINT;
|
|
|
|
message_type = READ_ONCE(msg->header.message_type);
|
|
if (message_type == HVMSG_NONE)
|
|
continue;
|
|
|
|
hdr = (struct vmbus_channel_message_header *)
|
|
msg->u.payload;
|
|
|
|
if (hdr->msgtype == CHANNELMSG_UNLOAD_RESPONSE)
|
|
complete(&vmbus_connection.unload_event);
|
|
|
|
vmbus_signal_eom(msg, message_type);
|
|
}
|
|
|
|
/*
|
|
* Give a notice periodically so someone watching the
|
|
* serial output won't think it is completely hung.
|
|
*/
|
|
if (!(i % UNLOAD_MSG_LOOPS))
|
|
pr_notice("Waiting for VMBus UNLOAD to complete\n");
|
|
|
|
mdelay(UNLOAD_DELAY_UNIT_MS);
|
|
}
|
|
pr_err("Continuing even though VMBus UNLOAD did not complete\n");
|
|
|
|
completed:
|
|
/*
|
|
* We're crashing and already got the UNLOAD_RESPONSE, cleanup all
|
|
* maybe-pending messages on all CPUs to be able to receive new
|
|
* messages after we reconnect.
|
|
*/
|
|
for_each_present_cpu(cpu) {
|
|
struct hv_per_cpu_context *hv_cpu
|
|
= per_cpu_ptr(hv_context.cpu_context, cpu);
|
|
|
|
page_addr = hv_cpu->synic_message_page;
|
|
if (!page_addr)
|
|
continue;
|
|
|
|
msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
|
|
msg->header.message_type = HVMSG_NONE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vmbus_unload_response - Handler for the unload response.
|
|
*/
|
|
static void vmbus_unload_response(struct vmbus_channel_message_header *hdr)
|
|
{
|
|
/*
|
|
* This is a global event; just wakeup the waiting thread.
|
|
* Once we successfully unload, we can cleanup the monitor state.
|
|
*
|
|
* NB. A malicious or compromised Hyper-V could send a spurious
|
|
* message of type CHANNELMSG_UNLOAD_RESPONSE, and trigger a call
|
|
* of the complete() below. Make sure that unload_event has been
|
|
* initialized by the time this complete() is executed.
|
|
*/
|
|
complete(&vmbus_connection.unload_event);
|
|
}
|
|
|
|
void vmbus_initiate_unload(bool crash)
|
|
{
|
|
struct vmbus_channel_message_header hdr;
|
|
|
|
if (xchg(&vmbus_connection.conn_state, DISCONNECTED) == DISCONNECTED)
|
|
return;
|
|
|
|
/* Pre-Win2012R2 hosts don't support reconnect */
|
|
if (vmbus_proto_version < VERSION_WIN8_1)
|
|
return;
|
|
|
|
reinit_completion(&vmbus_connection.unload_event);
|
|
memset(&hdr, 0, sizeof(struct vmbus_channel_message_header));
|
|
hdr.msgtype = CHANNELMSG_UNLOAD;
|
|
vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header),
|
|
!crash);
|
|
|
|
/*
|
|
* vmbus_initiate_unload() is also called on crash and the crash can be
|
|
* happening in an interrupt context, where scheduling is impossible.
|
|
*/
|
|
if (!crash)
|
|
wait_for_completion(&vmbus_connection.unload_event);
|
|
else
|
|
vmbus_wait_for_unload();
|
|
}
|
|
|
|
static void check_ready_for_resume_event(void)
|
|
{
|
|
/*
|
|
* If all the old primary channels have been fixed up, then it's safe
|
|
* to resume.
|
|
*/
|
|
if (atomic_dec_and_test(&vmbus_connection.nr_chan_fixup_on_resume))
|
|
complete(&vmbus_connection.ready_for_resume_event);
|
|
}
|
|
|
|
static void vmbus_setup_channel_state(struct vmbus_channel *channel,
|
|
struct vmbus_channel_offer_channel *offer)
|
|
{
|
|
/*
|
|
* Setup state for signalling the host.
|
|
*/
|
|
channel->sig_event = VMBUS_EVENT_CONNECTION_ID;
|
|
|
|
channel->is_dedicated_interrupt =
|
|
(offer->is_dedicated_interrupt != 0);
|
|
channel->sig_event = offer->connection_id;
|
|
|
|
memcpy(&channel->offermsg, offer,
|
|
sizeof(struct vmbus_channel_offer_channel));
|
|
channel->monitor_grp = (u8)offer->monitorid / 32;
|
|
channel->monitor_bit = (u8)offer->monitorid % 32;
|
|
channel->device_id = hv_get_dev_type(channel);
|
|
}
|
|
|
|
/*
|
|
* find_primary_channel_by_offer - Get the channel object given the new offer.
|
|
* This is only used in the resume path of hibernation.
|
|
*/
|
|
static struct vmbus_channel *
|
|
find_primary_channel_by_offer(const struct vmbus_channel_offer_channel *offer)
|
|
{
|
|
struct vmbus_channel *channel = NULL, *iter;
|
|
const guid_t *inst1, *inst2;
|
|
|
|
/* Ignore sub-channel offers. */
|
|
if (offer->offer.sub_channel_index != 0)
|
|
return NULL;
|
|
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
|
|
list_for_each_entry(iter, &vmbus_connection.chn_list, listentry) {
|
|
inst1 = &iter->offermsg.offer.if_instance;
|
|
inst2 = &offer->offer.if_instance;
|
|
|
|
if (guid_equal(inst1, inst2)) {
|
|
channel = iter;
|
|
break;
|
|
}
|
|
}
|
|
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
|
|
return channel;
|
|
}
|
|
|
|
static bool vmbus_is_valid_offer(const struct vmbus_channel_offer_channel *offer)
|
|
{
|
|
const guid_t *guid = &offer->offer.if_type;
|
|
u16 i;
|
|
|
|
if (!hv_is_isolation_supported())
|
|
return true;
|
|
|
|
if (is_hvsock_offer(offer))
|
|
return true;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(vmbus_devs); i++) {
|
|
if (guid_equal(guid, &vmbus_devs[i].guid))
|
|
return vmbus_devs[i].allowed_in_isolated;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
|
|
*
|
|
*/
|
|
static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
|
|
{
|
|
struct vmbus_channel_offer_channel *offer;
|
|
struct vmbus_channel *oldchannel, *newchannel;
|
|
size_t offer_sz;
|
|
|
|
offer = (struct vmbus_channel_offer_channel *)hdr;
|
|
|
|
trace_vmbus_onoffer(offer);
|
|
|
|
if (!vmbus_is_valid_offer(offer)) {
|
|
pr_err_ratelimited("Invalid offer %d from the host supporting isolation\n",
|
|
offer->child_relid);
|
|
atomic_dec(&vmbus_connection.offer_in_progress);
|
|
return;
|
|
}
|
|
|
|
oldchannel = find_primary_channel_by_offer(offer);
|
|
|
|
if (oldchannel != NULL) {
|
|
/*
|
|
* We're resuming from hibernation: all the sub-channel and
|
|
* hv_sock channels we had before the hibernation should have
|
|
* been cleaned up, and now we must be seeing a re-offered
|
|
* primary channel that we had before the hibernation.
|
|
*/
|
|
|
|
/*
|
|
* { Initially: channel relid = INVALID_RELID,
|
|
* channels[valid_relid] = NULL }
|
|
*
|
|
* CPU1 CPU2
|
|
*
|
|
* [vmbus_onoffer()] [vmbus_device_release()]
|
|
*
|
|
* LOCK channel_mutex LOCK channel_mutex
|
|
* STORE channel relid = valid_relid LOAD r1 = channel relid
|
|
* MAP_RELID channel if (r1 != INVALID_RELID)
|
|
* UNLOCK channel_mutex UNMAP_RELID channel
|
|
* UNLOCK channel_mutex
|
|
*
|
|
* Forbids: r1 == valid_relid &&
|
|
* channels[valid_relid] == channel
|
|
*
|
|
* Note. r1 can be INVALID_RELID only for an hv_sock channel.
|
|
* None of the hv_sock channels which were present before the
|
|
* suspend are re-offered upon the resume. See the WARN_ON()
|
|
* in hv_process_channel_removal().
|
|
*/
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
|
|
atomic_dec(&vmbus_connection.offer_in_progress);
|
|
|
|
WARN_ON(oldchannel->offermsg.child_relid != INVALID_RELID);
|
|
/* Fix up the relid. */
|
|
oldchannel->offermsg.child_relid = offer->child_relid;
|
|
|
|
offer_sz = sizeof(*offer);
|
|
if (memcmp(offer, &oldchannel->offermsg, offer_sz) != 0) {
|
|
/*
|
|
* This is not an error, since the host can also change
|
|
* the other field(s) of the offer, e.g. on WS RS5
|
|
* (Build 17763), the offer->connection_id of the
|
|
* Mellanox VF vmbus device can change when the host
|
|
* reoffers the device upon resume.
|
|
*/
|
|
pr_debug("vmbus offer changed: relid=%d\n",
|
|
offer->child_relid);
|
|
|
|
print_hex_dump_debug("Old vmbus offer: ",
|
|
DUMP_PREFIX_OFFSET, 16, 4,
|
|
&oldchannel->offermsg, offer_sz,
|
|
false);
|
|
print_hex_dump_debug("New vmbus offer: ",
|
|
DUMP_PREFIX_OFFSET, 16, 4,
|
|
offer, offer_sz, false);
|
|
|
|
/* Fix up the old channel. */
|
|
vmbus_setup_channel_state(oldchannel, offer);
|
|
}
|
|
|
|
/* Add the channel back to the array of channels. */
|
|
vmbus_channel_map_relid(oldchannel);
|
|
check_ready_for_resume_event();
|
|
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
return;
|
|
}
|
|
|
|
/* Allocate the channel object and save this offer. */
|
|
newchannel = alloc_channel();
|
|
if (!newchannel) {
|
|
vmbus_release_relid(offer->child_relid);
|
|
atomic_dec(&vmbus_connection.offer_in_progress);
|
|
pr_err("Unable to allocate channel object\n");
|
|
return;
|
|
}
|
|
|
|
vmbus_setup_channel_state(newchannel, offer);
|
|
|
|
vmbus_process_offer(newchannel);
|
|
}
|
|
|
|
static void check_ready_for_suspend_event(void)
|
|
{
|
|
/*
|
|
* If all the sub-channels or hv_sock channels have been cleaned up,
|
|
* then it's safe to suspend.
|
|
*/
|
|
if (atomic_dec_and_test(&vmbus_connection.nr_chan_close_on_suspend))
|
|
complete(&vmbus_connection.ready_for_suspend_event);
|
|
}
|
|
|
|
/*
|
|
* vmbus_onoffer_rescind - Rescind offer handler.
|
|
*
|
|
* We queue a work item to process this offer synchronously
|
|
*/
|
|
static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
|
|
{
|
|
struct vmbus_channel_rescind_offer *rescind;
|
|
struct vmbus_channel *channel;
|
|
struct device *dev;
|
|
bool clean_up_chan_for_suspend;
|
|
|
|
rescind = (struct vmbus_channel_rescind_offer *)hdr;
|
|
|
|
trace_vmbus_onoffer_rescind(rescind);
|
|
|
|
/*
|
|
* The offer msg and the corresponding rescind msg
|
|
* from the host are guranteed to be ordered -
|
|
* offer comes in first and then the rescind.
|
|
* Since we process these events in work elements,
|
|
* and with preemption, we may end up processing
|
|
* the events out of order. We rely on the synchronization
|
|
* provided by offer_in_progress and by channel_mutex for
|
|
* ordering these events:
|
|
*
|
|
* { Initially: offer_in_progress = 1 }
|
|
*
|
|
* CPU1 CPU2
|
|
*
|
|
* [vmbus_onoffer()] [vmbus_onoffer_rescind()]
|
|
*
|
|
* LOCK channel_mutex WAIT_ON offer_in_progress == 0
|
|
* DECREMENT offer_in_progress LOCK channel_mutex
|
|
* STORE channels[] LOAD channels[]
|
|
* UNLOCK channel_mutex UNLOCK channel_mutex
|
|
*
|
|
* Forbids: CPU2's LOAD from *not* seeing CPU1's STORE
|
|
*/
|
|
|
|
while (atomic_read(&vmbus_connection.offer_in_progress) != 0) {
|
|
/*
|
|
* We wait here until any channel offer is currently
|
|
* being processed.
|
|
*/
|
|
msleep(1);
|
|
}
|
|
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
channel = relid2channel(rescind->child_relid);
|
|
if (channel != NULL) {
|
|
/*
|
|
* Guarantee that no other instance of vmbus_onoffer_rescind()
|
|
* has got a reference to the channel object. Synchronize on
|
|
* &vmbus_connection.channel_mutex.
|
|
*/
|
|
if (channel->rescind_ref) {
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
return;
|
|
}
|
|
channel->rescind_ref = true;
|
|
}
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
|
|
if (channel == NULL) {
|
|
/*
|
|
* We failed in processing the offer message;
|
|
* we would have cleaned up the relid in that
|
|
* failure path.
|
|
*/
|
|
return;
|
|
}
|
|
|
|
clean_up_chan_for_suspend = is_hvsock_channel(channel) ||
|
|
is_sub_channel(channel);
|
|
/*
|
|
* Before setting channel->rescind in vmbus_rescind_cleanup(), we
|
|
* should make sure the channel callback is not running any more.
|
|
*/
|
|
vmbus_reset_channel_cb(channel);
|
|
|
|
/*
|
|
* Now wait for offer handling to complete.
|
|
*/
|
|
vmbus_rescind_cleanup(channel);
|
|
while (READ_ONCE(channel->probe_done) == false) {
|
|
/*
|
|
* We wait here until any channel offer is currently
|
|
* being processed.
|
|
*/
|
|
msleep(1);
|
|
}
|
|
|
|
/*
|
|
* At this point, the rescind handling can proceed safely.
|
|
*/
|
|
|
|
if (channel->device_obj) {
|
|
if (channel->chn_rescind_callback) {
|
|
channel->chn_rescind_callback(channel);
|
|
|
|
if (clean_up_chan_for_suspend)
|
|
check_ready_for_suspend_event();
|
|
|
|
return;
|
|
}
|
|
/*
|
|
* We will have to unregister this device from the
|
|
* driver core.
|
|
*/
|
|
dev = get_device(&channel->device_obj->device);
|
|
if (dev) {
|
|
vmbus_device_unregister(channel->device_obj);
|
|
put_device(dev);
|
|
}
|
|
} else if (channel->primary_channel != NULL) {
|
|
/*
|
|
* Sub-channel is being rescinded. Following is the channel
|
|
* close sequence when initiated from the driveri (refer to
|
|
* vmbus_close() for details):
|
|
* 1. Close all sub-channels first
|
|
* 2. Then close the primary channel.
|
|
*/
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
if (channel->state == CHANNEL_OPEN_STATE) {
|
|
/*
|
|
* The channel is currently not open;
|
|
* it is safe for us to cleanup the channel.
|
|
*/
|
|
hv_process_channel_removal(channel);
|
|
} else {
|
|
complete(&channel->rescind_event);
|
|
}
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
}
|
|
|
|
/* The "channel" may have been freed. Do not access it any longer. */
|
|
|
|
if (clean_up_chan_for_suspend)
|
|
check_ready_for_suspend_event();
|
|
}
|
|
|
|
void vmbus_hvsock_device_unregister(struct vmbus_channel *channel)
|
|
{
|
|
BUG_ON(!is_hvsock_channel(channel));
|
|
|
|
/* We always get a rescind msg when a connection is closed. */
|
|
while (!READ_ONCE(channel->probe_done) || !READ_ONCE(channel->rescind))
|
|
msleep(1);
|
|
|
|
vmbus_device_unregister(channel->device_obj);
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_hvsock_device_unregister);
|
|
|
|
|
|
/*
|
|
* vmbus_onoffers_delivered -
|
|
* This is invoked when all offers have been delivered.
|
|
*
|
|
* Nothing to do here.
|
|
*/
|
|
static void vmbus_onoffers_delivered(
|
|
struct vmbus_channel_message_header *hdr)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* vmbus_onopen_result - Open result handler.
|
|
*
|
|
* This is invoked when we received a response to our channel open request.
|
|
* Find the matching request, copy the response and signal the requesting
|
|
* thread.
|
|
*/
|
|
static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
|
|
{
|
|
struct vmbus_channel_open_result *result;
|
|
struct vmbus_channel_msginfo *msginfo;
|
|
struct vmbus_channel_message_header *requestheader;
|
|
struct vmbus_channel_open_channel *openmsg;
|
|
unsigned long flags;
|
|
|
|
result = (struct vmbus_channel_open_result *)hdr;
|
|
|
|
trace_vmbus_onopen_result(result);
|
|
|
|
/*
|
|
* Find the open msg, copy the result and signal/unblock the wait event
|
|
*/
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
|
|
msglistentry) {
|
|
requestheader =
|
|
(struct vmbus_channel_message_header *)msginfo->msg;
|
|
|
|
if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
|
|
openmsg =
|
|
(struct vmbus_channel_open_channel *)msginfo->msg;
|
|
if (openmsg->child_relid == result->child_relid &&
|
|
openmsg->openid == result->openid) {
|
|
memcpy(&msginfo->response.open_result,
|
|
result,
|
|
sizeof(
|
|
struct vmbus_channel_open_result));
|
|
complete(&msginfo->waitevent);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* vmbus_ongpadl_created - GPADL created handler.
|
|
*
|
|
* This is invoked when we received a response to our gpadl create request.
|
|
* Find the matching request, copy the response and signal the requesting
|
|
* thread.
|
|
*/
|
|
static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
|
|
{
|
|
struct vmbus_channel_gpadl_created *gpadlcreated;
|
|
struct vmbus_channel_msginfo *msginfo;
|
|
struct vmbus_channel_message_header *requestheader;
|
|
struct vmbus_channel_gpadl_header *gpadlheader;
|
|
unsigned long flags;
|
|
|
|
gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
|
|
|
|
trace_vmbus_ongpadl_created(gpadlcreated);
|
|
|
|
/*
|
|
* Find the establish msg, copy the result and signal/unblock the wait
|
|
* event
|
|
*/
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
|
|
msglistentry) {
|
|
requestheader =
|
|
(struct vmbus_channel_message_header *)msginfo->msg;
|
|
|
|
if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
|
|
gpadlheader =
|
|
(struct vmbus_channel_gpadl_header *)requestheader;
|
|
|
|
if ((gpadlcreated->child_relid ==
|
|
gpadlheader->child_relid) &&
|
|
(gpadlcreated->gpadl == gpadlheader->gpadl)) {
|
|
memcpy(&msginfo->response.gpadl_created,
|
|
gpadlcreated,
|
|
sizeof(
|
|
struct vmbus_channel_gpadl_created));
|
|
complete(&msginfo->waitevent);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* vmbus_onmodifychannel_response - Modify Channel response handler.
|
|
*
|
|
* This is invoked when we received a response to our channel modify request.
|
|
* Find the matching request, copy the response and signal the requesting thread.
|
|
*/
|
|
static void vmbus_onmodifychannel_response(struct vmbus_channel_message_header *hdr)
|
|
{
|
|
struct vmbus_channel_modifychannel_response *response;
|
|
struct vmbus_channel_msginfo *msginfo;
|
|
unsigned long flags;
|
|
|
|
response = (struct vmbus_channel_modifychannel_response *)hdr;
|
|
|
|
trace_vmbus_onmodifychannel_response(response);
|
|
|
|
/*
|
|
* Find the modify msg, copy the response and signal/unblock the wait event.
|
|
*/
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, msglistentry) {
|
|
struct vmbus_channel_message_header *responseheader =
|
|
(struct vmbus_channel_message_header *)msginfo->msg;
|
|
|
|
if (responseheader->msgtype == CHANNELMSG_MODIFYCHANNEL) {
|
|
struct vmbus_channel_modifychannel *modifymsg;
|
|
|
|
modifymsg = (struct vmbus_channel_modifychannel *)msginfo->msg;
|
|
if (modifymsg->child_relid == response->child_relid) {
|
|
memcpy(&msginfo->response.modify_response, response,
|
|
sizeof(*response));
|
|
complete(&msginfo->waitevent);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* vmbus_ongpadl_torndown - GPADL torndown handler.
|
|
*
|
|
* This is invoked when we received a response to our gpadl teardown request.
|
|
* Find the matching request, copy the response and signal the requesting
|
|
* thread.
|
|
*/
|
|
static void vmbus_ongpadl_torndown(
|
|
struct vmbus_channel_message_header *hdr)
|
|
{
|
|
struct vmbus_channel_gpadl_torndown *gpadl_torndown;
|
|
struct vmbus_channel_msginfo *msginfo;
|
|
struct vmbus_channel_message_header *requestheader;
|
|
struct vmbus_channel_gpadl_teardown *gpadl_teardown;
|
|
unsigned long flags;
|
|
|
|
gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
|
|
|
|
trace_vmbus_ongpadl_torndown(gpadl_torndown);
|
|
|
|
/*
|
|
* Find the open msg, copy the result and signal/unblock the wait event
|
|
*/
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
|
|
msglistentry) {
|
|
requestheader =
|
|
(struct vmbus_channel_message_header *)msginfo->msg;
|
|
|
|
if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
|
|
gpadl_teardown =
|
|
(struct vmbus_channel_gpadl_teardown *)requestheader;
|
|
|
|
if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
|
|
memcpy(&msginfo->response.gpadl_torndown,
|
|
gpadl_torndown,
|
|
sizeof(
|
|
struct vmbus_channel_gpadl_torndown));
|
|
complete(&msginfo->waitevent);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* vmbus_onversion_response - Version response handler
|
|
*
|
|
* This is invoked when we received a response to our initiate contact request.
|
|
* Find the matching request, copy the response and signal the requesting
|
|
* thread.
|
|
*/
|
|
static void vmbus_onversion_response(
|
|
struct vmbus_channel_message_header *hdr)
|
|
{
|
|
struct vmbus_channel_msginfo *msginfo;
|
|
struct vmbus_channel_message_header *requestheader;
|
|
struct vmbus_channel_version_response *version_response;
|
|
unsigned long flags;
|
|
|
|
version_response = (struct vmbus_channel_version_response *)hdr;
|
|
|
|
trace_vmbus_onversion_response(version_response);
|
|
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
|
|
msglistentry) {
|
|
requestheader =
|
|
(struct vmbus_channel_message_header *)msginfo->msg;
|
|
|
|
if (requestheader->msgtype ==
|
|
CHANNELMSG_INITIATE_CONTACT) {
|
|
memcpy(&msginfo->response.version_response,
|
|
version_response,
|
|
sizeof(struct vmbus_channel_version_response));
|
|
complete(&msginfo->waitevent);
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
}
|
|
|
|
/* Channel message dispatch table */
|
|
const struct vmbus_channel_message_table_entry
|
|
channel_message_table[CHANNELMSG_COUNT] = {
|
|
{ CHANNELMSG_INVALID, 0, NULL, 0},
|
|
{ CHANNELMSG_OFFERCHANNEL, 0, vmbus_onoffer,
|
|
sizeof(struct vmbus_channel_offer_channel)},
|
|
{ CHANNELMSG_RESCIND_CHANNELOFFER, 0, vmbus_onoffer_rescind,
|
|
sizeof(struct vmbus_channel_rescind_offer) },
|
|
{ CHANNELMSG_REQUESTOFFERS, 0, NULL, 0},
|
|
{ CHANNELMSG_ALLOFFERS_DELIVERED, 1, vmbus_onoffers_delivered, 0},
|
|
{ CHANNELMSG_OPENCHANNEL, 0, NULL, 0},
|
|
{ CHANNELMSG_OPENCHANNEL_RESULT, 1, vmbus_onopen_result,
|
|
sizeof(struct vmbus_channel_open_result)},
|
|
{ CHANNELMSG_CLOSECHANNEL, 0, NULL, 0},
|
|
{ CHANNELMSG_GPADL_HEADER, 0, NULL, 0},
|
|
{ CHANNELMSG_GPADL_BODY, 0, NULL, 0},
|
|
{ CHANNELMSG_GPADL_CREATED, 1, vmbus_ongpadl_created,
|
|
sizeof(struct vmbus_channel_gpadl_created)},
|
|
{ CHANNELMSG_GPADL_TEARDOWN, 0, NULL, 0},
|
|
{ CHANNELMSG_GPADL_TORNDOWN, 1, vmbus_ongpadl_torndown,
|
|
sizeof(struct vmbus_channel_gpadl_torndown) },
|
|
{ CHANNELMSG_RELID_RELEASED, 0, NULL, 0},
|
|
{ CHANNELMSG_INITIATE_CONTACT, 0, NULL, 0},
|
|
{ CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response,
|
|
sizeof(struct vmbus_channel_version_response)},
|
|
{ CHANNELMSG_UNLOAD, 0, NULL, 0},
|
|
{ CHANNELMSG_UNLOAD_RESPONSE, 1, vmbus_unload_response, 0},
|
|
{ CHANNELMSG_18, 0, NULL, 0},
|
|
{ CHANNELMSG_19, 0, NULL, 0},
|
|
{ CHANNELMSG_20, 0, NULL, 0},
|
|
{ CHANNELMSG_TL_CONNECT_REQUEST, 0, NULL, 0},
|
|
{ CHANNELMSG_MODIFYCHANNEL, 0, NULL, 0},
|
|
{ CHANNELMSG_TL_CONNECT_RESULT, 0, NULL, 0},
|
|
{ CHANNELMSG_MODIFYCHANNEL_RESPONSE, 1, vmbus_onmodifychannel_response,
|
|
sizeof(struct vmbus_channel_modifychannel_response)},
|
|
};
|
|
|
|
/*
|
|
* vmbus_onmessage - Handler for channel protocol messages.
|
|
*
|
|
* This is invoked in the vmbus worker thread context.
|
|
*/
|
|
void vmbus_onmessage(struct vmbus_channel_message_header *hdr)
|
|
{
|
|
trace_vmbus_on_message(hdr);
|
|
|
|
/*
|
|
* vmbus_on_msg_dpc() makes sure the hdr->msgtype here can not go
|
|
* out of bound and the message_handler pointer can not be NULL.
|
|
*/
|
|
channel_message_table[hdr->msgtype].message_handler(hdr);
|
|
}
|
|
|
|
/*
|
|
* vmbus_request_offers - Send a request to get all our pending offers.
|
|
*/
|
|
int vmbus_request_offers(void)
|
|
{
|
|
struct vmbus_channel_message_header *msg;
|
|
struct vmbus_channel_msginfo *msginfo;
|
|
int ret;
|
|
|
|
msginfo = kzalloc(sizeof(*msginfo) +
|
|
sizeof(struct vmbus_channel_message_header),
|
|
GFP_KERNEL);
|
|
if (!msginfo)
|
|
return -ENOMEM;
|
|
|
|
msg = (struct vmbus_channel_message_header *)msginfo->msg;
|
|
|
|
msg->msgtype = CHANNELMSG_REQUESTOFFERS;
|
|
|
|
ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_message_header),
|
|
true);
|
|
|
|
trace_vmbus_request_offers(ret);
|
|
|
|
if (ret != 0) {
|
|
pr_err("Unable to request offers - %d\n", ret);
|
|
|
|
goto cleanup;
|
|
}
|
|
|
|
cleanup:
|
|
kfree(msginfo);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
|
|
void (*sc_cr_cb)(struct vmbus_channel *new_sc))
|
|
{
|
|
primary_channel->sc_creation_callback = sc_cr_cb;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback);
|
|
|
|
void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
|
|
void (*chn_rescind_cb)(struct vmbus_channel *))
|
|
{
|
|
channel->chn_rescind_callback = chn_rescind_cb;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_set_chn_rescind_callback);
|