diff options
Diffstat (limited to 'drivers/hv/channel_mgmt.c')
| -rw-r--r-- | drivers/hv/channel_mgmt.c | 989 |
1 files changed, 659 insertions, 330 deletions
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index d01689079e9b..74fed2c073d4 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -1,19 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2009, Microsoft Corporation. * - * This program is free software; you can redistribute it and/or modify it - * under the terms and conditions of the GNU General Public License, - * version 2, as published by the Free Software Foundation. - * - * This program is distributed in the hope it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should have received a copy of the GNU General Public License along with - * this program; if not, write to the Free Software Foundation, Inc., 59 Temple - * Place - Suite 330, Boston, MA 02111-1307 USA. - * * Authors: * Haiyang Zhang <haiyangz@microsoft.com> * Hank Janssen <hjanssen@microsoft.com> @@ -30,122 +18,152 @@ #include <linux/module.h> #include <linux/completion.h> #include <linux/delay.h> +#include <linux/cpu.h> #include <linux/hyperv.h> +#include <linux/export.h> #include <asm/mshyperv.h> +#include <linux/sched/isolation.h> #include "hyperv_vmbus.h" -static void init_vp_index(struct vmbus_channel *channel, u16 dev_type); +static void init_vp_index(struct vmbus_channel *channel); -static const struct vmbus_device vmbus_devs[] = { +const struct vmbus_device vmbus_devs[] = { /* IDE */ { .dev_type = HV_IDE, HV_IDE_GUID, .perf_device = true, + .allowed_in_isolated = false, }, /* SCSI */ { .dev_type = HV_SCSI, HV_SCSI_GUID, .perf_device = true, + .allowed_in_isolated = true, }, /* Fibre Channel */ { .dev_type = HV_FC, HV_SYNTHFC_GUID, .perf_device = true, + .allowed_in_isolated = false, }, /* Synthetic NIC */ { .dev_type = HV_NIC, HV_NIC_GUID, .perf_device = true, + .allowed_in_isolated = true, }, /* Network Direct */ { .dev_type = HV_ND, HV_ND_GUID, .perf_device = true, + .allowed_in_isolated = false, }, /* PCIE */ { .dev_type = HV_PCIE, HV_PCIE_GUID, .perf_device = false, + .allowed_in_isolated = true, }, /* Synthetic Frame Buffer */ { .dev_type = HV_FB, HV_SYNTHVID_GUID, .perf_device = false, + .allowed_in_isolated = false, }, /* Synthetic Keyboard */ { .dev_type = HV_KBD, HV_KBD_GUID, .perf_device = false, + .allowed_in_isolated = false, }, /* Synthetic MOUSE */ { .dev_type = HV_MOUSE, HV_MOUSE_GUID, .perf_device = false, + .allowed_in_isolated = false, }, /* KVP */ { .dev_type = HV_KVP, HV_KVP_GUID, .perf_device = false, + .allowed_in_isolated = false, }, /* Time Synch */ { .dev_type = HV_TS, HV_TS_GUID, .perf_device = false, + .allowed_in_isolated = true, }, /* Heartbeat */ { .dev_type = HV_HB, HV_HEART_BEAT_GUID, .perf_device = false, + .allowed_in_isolated = true, }, /* Shutdown */ { .dev_type = HV_SHUTDOWN, HV_SHUTDOWN_GUID, .perf_device = false, + .allowed_in_isolated = true, }, /* File copy */ - { .dev_type = HV_FCOPY, + /* fcopy always uses 16KB ring buffer size and is working well for last many years */ + { .pref_ring_size = 0x4000, + .dev_type = HV_FCOPY, HV_FCOPY_GUID, .perf_device = false, + .allowed_in_isolated = false, }, /* Backup */ { .dev_type = HV_BACKUP, HV_VSS_GUID, .perf_device = false, + .allowed_in_isolated = false, }, /* Dynamic Memory */ { .dev_type = HV_DM, HV_DM_GUID, .perf_device = false, + .allowed_in_isolated = false, }, - /* Unknown GUID */ - { .dev_type = HV_UNKNOWN, + /* + * Unknown GUID + * 64 KB ring buffer + 4 KB header should be sufficient size for any Hyper-V device apart + * from HV_NIC and HV_SCSI. This case avoid the fallback for unknown devices to allocate + * much bigger (2 MB) of ring size. + */ + { .pref_ring_size = 0x11000, + .dev_type = HV_UNKNOWN, .perf_device = false, + .allowed_in_isolated = false, }, }; +EXPORT_SYMBOL_GPL(vmbus_devs); static const struct { - uuid_le guid; + guid_t guid; } vmbus_unsupported_devs[] = { { HV_AVMA1_GUID }, { HV_AVMA2_GUID }, { HV_RDV_GUID }, + { HV_IMC_GUID }, }; /* @@ -171,26 +189,26 @@ static void vmbus_rescind_cleanup(struct vmbus_channel *channel) spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); } -static bool is_unsupported_vmbus_devs(const uuid_le *guid) +static bool is_unsupported_vmbus_devs(const guid_t *guid) { int i; for (i = 0; i < ARRAY_SIZE(vmbus_unsupported_devs); i++) - if (!uuid_le_cmp(*guid, vmbus_unsupported_devs[i].guid)) + if (guid_equal(guid, &vmbus_unsupported_devs[i].guid)) return true; return false; } static u16 hv_get_dev_type(const struct vmbus_channel *channel) { - const uuid_le *guid = &channel->offermsg.offer.if_type; + const guid_t *guid = &channel->offermsg.offer.if_type; u16 i; if (is_hvsock_channel(channel) || is_unsupported_vmbus_devs(guid)) return HV_UNKNOWN; for (i = HV_IDE; i < HV_UNKNOWN; i++) { - if (!uuid_le_cmp(*guid, vmbus_devs[i].guid)) + if (guid_equal(guid, &vmbus_devs[i].guid)) return i; } pr_info("Unknown GUID: %pUl\n", guid); @@ -201,6 +219,7 @@ static u16 hv_get_dev_type(const struct vmbus_channel *channel) * vmbus_prep_negotiate_resp() - Create default response for Negotiate message * @icmsghdrp: Pointer to msg header structure * @buf: Raw buffer channel data + * @buflen: Length of the raw buffer channel data. * @fw_version: The framework versions we can support. * @fw_vercnt: The size of @fw_version. * @srv_version: The service versions we can support. @@ -213,8 +232,8 @@ static u16 hv_get_dev_type(const struct vmbus_channel *channel) * Set up and fill in default negotiate response message. * Mainly used by Hyper-V drivers. */ -bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, - u8 *buf, const int *fw_version, int fw_vercnt, +bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, u8 *buf, + u32 buflen, const int *fw_version, int fw_vercnt, const int *srv_version, int srv_vercnt, int *nego_fw_version, int *nego_srv_version) { @@ -226,10 +245,14 @@ bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, bool found_match = false; struct icmsg_negotiate *negop; + /* Check that there's enough space for icframe_vercnt, icmsg_vercnt */ + if (buflen < ICMSG_HDR + offsetof(struct icmsg_negotiate, reserved)) { + pr_err_ratelimited("Invalid icmsg negotiate\n"); + return false; + } + icmsghdrp->icmsgsize = 0x10; - negop = (struct icmsg_negotiate *)&buf[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + negop = (struct icmsg_negotiate *)&buf[ICMSG_HDR]; icframe_major = negop->icframe_vercnt; icframe_minor = 0; @@ -237,6 +260,15 @@ bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, icmsg_major = negop->icmsg_vercnt; icmsg_minor = 0; + /* Validate negop packet */ + if (icframe_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT || + icmsg_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT || + ICMSG_NEGOTIATE_PKT_SIZE(icframe_major, icmsg_major) > buflen) { + pr_err_ratelimited("Invalid icmsg negotiate - icframe_major: %u, icmsg_major: %u\n", + icframe_major, icmsg_major); + goto fw_error; + } + /* * Select the framework version number we will * support. @@ -313,7 +345,6 @@ fw_error: negop->icversion_data[1].minor = icmsg_minor; return found_match; } - EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp); /* @@ -327,15 +358,16 @@ static struct vmbus_channel *alloc_channel(void) if (!channel) return NULL; - spin_lock_init(&channel->lock); + spin_lock_init(&channel->sched_lock); init_completion(&channel->rescind_event); INIT_LIST_HEAD(&channel->sc_list); - INIT_LIST_HEAD(&channel->percpu_list); tasklet_init(&channel->callback_event, vmbus_on_event, (unsigned long)channel); + hv_ringbuffer_pre_init(channel); + return channel; } @@ -345,27 +377,54 @@ static struct vmbus_channel *alloc_channel(void) static void free_channel(struct vmbus_channel *channel) { tasklet_kill(&channel->callback_event); + vmbus_remove_channel_attr_group(channel); kobject_put(&channel->kobj); } -static void percpu_channel_enq(void *arg) +void vmbus_channel_map_relid(struct vmbus_channel *channel) { - struct vmbus_channel *channel = arg; - struct hv_per_cpu_context *hv_cpu - = this_cpu_ptr(hv_context.cpu_context); - - list_add_tail_rcu(&channel->percpu_list, &hv_cpu->chan_list); + if (WARN_ON(channel->offermsg.child_relid >= MAX_CHANNEL_RELIDS)) + return; + /* + * The mapping of the channel's relid is visible from the CPUs that + * execute vmbus_chan_sched() by the time that vmbus_chan_sched() will + * execute: + * + * (a) In the "normal (i.e., not resuming from hibernation)" path, + * the full barrier in virt_store_mb() guarantees that the store + * is propagated to all CPUs before the add_channel_work work + * is queued. In turn, add_channel_work is queued before the + * channel's ring buffer is allocated/initialized and the + * OPENCHANNEL message for the channel is sent in vmbus_open(). + * Hyper-V won't start sending the interrupts for the channel + * before the OPENCHANNEL message is acked. The memory barrier + * in vmbus_chan_sched() -> sync_test_and_clear_bit() ensures + * that vmbus_chan_sched() must find the channel's relid in + * recv_int_page before retrieving the channel pointer from the + * array of channels. + * + * (b) In the "resuming from hibernation" path, the virt_store_mb() + * guarantees that the store is propagated to all CPUs before + * the VMBus connection is marked as ready for the resume event + * (cf. check_ready_for_resume_event()). The interrupt handler + * of the VMBus driver and vmbus_chan_sched() can not run before + * vmbus_bus_resume() has completed execution (cf. resume_noirq). + */ + virt_store_mb( + vmbus_connection.channels[channel->offermsg.child_relid], + channel); } -static void percpu_channel_deq(void *arg) +void vmbus_channel_unmap_relid(struct vmbus_channel *channel) { - struct vmbus_channel *channel = arg; - - list_del_rcu(&channel->percpu_list); + if (WARN_ON(channel->offermsg.child_relid >= MAX_CHANNEL_RELIDS)) + return; + WRITE_ONCE( + vmbus_connection.channels[channel->offermsg.child_relid], + NULL); } - static void vmbus_release_relid(u32 relid) { struct vmbus_channel_relid_released msg; @@ -382,41 +441,47 @@ static void vmbus_release_relid(u32 relid) void hv_process_channel_removal(struct vmbus_channel *channel) { - struct vmbus_channel *primary_channel; - unsigned long flags; - - BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex)); + lockdep_assert_held(&vmbus_connection.channel_mutex); BUG_ON(!channel->rescind); - if (channel->target_cpu != get_cpu()) { - put_cpu(); - smp_call_function_single(channel->target_cpu, - percpu_channel_deq, channel, true); - } else { - percpu_channel_deq(channel); - put_cpu(); - } + /* + * hv_process_channel_removal() could find INVALID_RELID only for + * hv_sock channels. See the inline comments in vmbus_onoffer(). + */ + WARN_ON(channel->offermsg.child_relid == INVALID_RELID && + !is_hvsock_channel(channel)); - if (channel->primary_channel == NULL) { - list_del(&channel->listentry); + /* + * Upon suspend, an in-use hv_sock channel is removed from the array of + * channels and the relid is invalidated. After hibernation, when the + * user-space application destroys the channel, it's unnecessary and + * unsafe to remove the channel from the array of channels. See also + * the inline comments before the call of vmbus_release_relid() below. + */ + if (channel->offermsg.child_relid != INVALID_RELID) + vmbus_channel_unmap_relid(channel); - primary_channel = channel; - } else { - primary_channel = channel->primary_channel; - spin_lock_irqsave(&primary_channel->lock, flags); + if (channel->primary_channel == NULL) + list_del(&channel->listentry); + else list_del(&channel->sc_list); - spin_unlock_irqrestore(&primary_channel->lock, flags); - } /* - * We need to free the bit for init_vp_index() to work in the case - * of sub-channel, when we reload drivers like hv_netvsc. + * If this is a "perf" channel, updates the hv_numa_map[] masks so that + * init_vp_index() can (re-)use the CPU. */ - if (channel->affinity_policy == HV_LOCALIZED) - cpumask_clear_cpu(channel->target_cpu, - &primary_channel->alloced_cpus_in_node); + if (hv_is_perf_channel(channel)) + hv_clear_allocated_cpu(channel->target_cpu); - vmbus_release_relid(channel->offermsg.child_relid); + /* + * Upon suspend, an in-use hv_sock channel is marked as "rescinded" and + * the relid is invalidated; after hibernation, when the user-space app + * destroys the channel, the relid is INVALID_RELID, and in this case + * it's unnecessary and unsafe to release the old relid, since the same + * relid can refer to a completely different channel now. + */ + if (channel->offermsg.child_relid != INVALID_RELID) + vmbus_release_relid(channel->offermsg.child_relid); free_channel(channel); } @@ -440,24 +505,8 @@ 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; - unsigned long flags; - u16 dev_type; int ret; - dev_type = hv_get_dev_type(newchannel); - - init_vp_index(newchannel, dev_type); - - if (newchannel->target_cpu != get_cpu()) { - put_cpu(); - smp_call_function_single(newchannel->target_cpu, - percpu_channel_enq, - newchannel, true); - } else { - percpu_channel_enq(newchannel); - put_cpu(); - } - /* * This state is used to indicate a successful open * so that when we do close the channel normally, we @@ -489,18 +538,22 @@ static void vmbus_add_channel_work(struct work_struct *work) if (!newchannel->device_obj) goto err_deq_chan; - newchannel->device_obj->device_id = dev_type; + 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); - kfree(newchannel->device_obj); goto err_deq_chan; } @@ -516,25 +569,15 @@ err_deq_chan: */ newchannel->probe_done = true; - if (primary_channel == NULL) { + if (primary_channel == NULL) list_del(&newchannel->listentry); - } else { - spin_lock_irqsave(&primary_channel->lock, flags); + else list_del(&newchannel->sc_list); - spin_unlock_irqrestore(&primary_channel->lock, flags); - } - mutex_unlock(&vmbus_connection.channel_mutex); + /* vmbus_process_offer() has mapped the channel. */ + vmbus_channel_unmap_relid(newchannel); - if (newchannel->target_cpu != get_cpu()) { - put_cpu(); - smp_call_function_single(newchannel->target_cpu, - percpu_channel_deq, - newchannel, true); - } else { - percpu_channel_deq(newchannel); - put_cpu(); - } + mutex_unlock(&vmbus_connection.channel_mutex); vmbus_release_relid(newchannel->offermsg.child_relid); @@ -549,36 +592,68 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel) { struct vmbus_channel *channel; struct workqueue_struct *wq; - unsigned long flags; bool fnew = true; - mutex_lock(&vmbus_connection.channel_mutex); + /* + * 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(); /* - * Now that we have acquired the channel_mutex, - * we can release the potentially racing rescind thread. + * Serializes the modifications of the chn_list list as well as + * the accesses to next_numa_node_id in init_vp_index(). */ - atomic_dec(&vmbus_connection.offer_in_progress); + mutex_lock(&vmbus_connection.channel_mutex); list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { - if (!uuid_le_cmp(channel->offermsg.offer.if_type, - newchannel->offermsg.offer.if_type) && - !uuid_le_cmp(channel->offermsg.offer.if_instance, - newchannel->offermsg.offer.if_instance)) { + 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; } } - if (fnew) + 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 { + } 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. @@ -590,13 +665,13 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel) /* * Process the sub-channel. */ - newchannel->primary_channel = channel; - spin_lock_irqsave(&channel->lock, flags); list_add_tail(&newchannel->sc_list, &channel->sc_list); - spin_unlock_irqrestore(&channel->lock, flags); } + vmbus_channel_map_relid(newchannel); + mutex_unlock(&vmbus_connection.channel_mutex); + cpus_read_unlock(); /* * vmbus_process_offer() mustn't call channel->sc_creation_callback() @@ -626,147 +701,122 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel) } /* - * We use this state to statically distribute the channel interrupt load. + * Check if CPUs used by other channels of the same device. + * It should only be called by init_vp_index(). */ -static int next_numa_node_id; +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; +} + /* - * init_vp_index() accesses global variables like next_numa_node_id, and - * it can run concurrently for primary channels and sub-channels: see - * vmbus_process_offer(), so we need the lock to protect the global - * variables. + * We use this state to statically distribute the channel interrupt load. */ -static DEFINE_SPINLOCK(bind_channel_to_cpu_lock); +static int next_numa_node_id; /* - * Starting with Win8, we can statically distribute the incoming - * channel interrupt load by binding a channel to VCPU. - * We distribute the interrupt loads to one or more NUMA nodes based on - * the channel's affinity_policy. + * We can statically distribute the incoming channel interrupt load + * by binding a channel to VCPU. * - * For pre-win8 hosts or non-performance critical channels we assign the - * first CPU in the first NUMA node. + * 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, u16 dev_type) +static void init_vp_index(struct vmbus_channel *channel) { - u32 cur_cpu; - bool perf_chn = vmbus_devs[dev_type].perf_device; - struct vmbus_channel *primary = channel->primary_channel; - int next_node; + bool perf_chn = hv_is_perf_channel(channel); + u32 i, ncpu = num_online_cpus(); cpumask_var_t available_mask; - struct cpumask *alloced_mask; - - if ((vmbus_proto_version == VERSION_WS2008) || - (vmbus_proto_version == VERSION_WIN7) || (!perf_chn) || - !alloc_cpumask_var(&available_mask, GFP_KERNEL)) { + 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)) { /* - * Prior to win8, all channel interrupts are - * delivered on cpu 0. - * Also if the channel is not a performance critical - * channel, bind it to cpu 0. - * In case alloc_cpumask_var() fails, bind it to cpu 0. + * 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->numa_node = 0; - channel->target_cpu = 0; - channel->target_vp = hv_cpu_number_to_vp_number(0); + channel->target_cpu = VMBUS_CONNECT_CPU; + if (perf_chn) + hv_set_allocated_cpu(VMBUS_CONNECT_CPU); return; } - spin_lock(&bind_channel_to_cpu_lock); - - /* - * Based on the channel affinity policy, we will assign the NUMA - * nodes. - */ - - if ((channel->affinity_policy == HV_BALANCED) || (!primary)) { + for (i = 1; i <= ncpu + 1; i++) { while (true) { - next_node = next_numa_node_id++; - if (next_node == nr_node_ids) { - next_node = next_numa_node_id = 0; + numa_node = next_numa_node_id++; + if (numa_node == nr_node_ids) { + next_numa_node_id = 0; continue; } - if (cpumask_empty(cpumask_of_node(next_node))) + if (cpumask_empty(cpumask_of_node(numa_node))) continue; break; } - channel->numa_node = next_node; - primary = channel; - } - alloced_mask = &hv_context.hv_numa_map[primary->numa_node]; - - if (cpumask_weight(alloced_mask) == - cpumask_weight(cpumask_of_node(primary->numa_node))) { - /* - * We have cycled through all the CPUs in the node; - * reset the alloced map. - */ - cpumask_clear(alloced_mask); - } - - cpumask_xor(available_mask, alloced_mask, - cpumask_of_node(primary->numa_node)); + allocated_mask = &hv_context.hv_numa_map[numa_node]; - cur_cpu = -1; +retry: + cpumask_xor(available_mask, allocated_mask, cpumask_of_node(numa_node)); + cpumask_and(available_mask, available_mask, hk_mask); - if (primary->affinity_policy == HV_LOCALIZED) { - /* - * Normally Hyper-V host doesn't create more subchannels - * than there are VCPUs on the node but it is possible when not - * all present VCPUs on the node are initialized by guest. - * Clear the alloced_cpus_in_node to start over. - */ - if (cpumask_equal(&primary->alloced_cpus_in_node, - cpumask_of_node(primary->numa_node))) - cpumask_clear(&primary->alloced_cpus_in_node); - } - - while (true) { - cur_cpu = cpumask_next(cur_cpu, available_mask); - if (cur_cpu >= nr_cpu_ids) { - cur_cpu = -1; - cpumask_copy(available_mask, - cpumask_of_node(primary->numa_node)); - continue; - } - - if (primary->affinity_policy == HV_LOCALIZED) { + if (cpumask_empty(available_mask)) { /* - * NOTE: in the case of sub-channel, we clear the - * sub-channel related bit(s) in - * primary->alloced_cpus_in_node in - * hv_process_channel_removal(), so when we - * reload drivers like hv_netvsc in SMP guest, here - * we're able to re-allocate - * bit from primary->alloced_cpus_in_node. + * We have cycled through all the CPUs in the node; + * reset the allocated map. */ - if (!cpumask_test_cpu(cur_cpu, - &primary->alloced_cpus_in_node)) { - cpumask_set_cpu(cur_cpu, - &primary->alloced_cpus_in_node); - cpumask_set_cpu(cur_cpu, alloced_mask); - break; - } - } else { - cpumask_set_cpu(cur_cpu, alloced_mask); - break; + cpumask_clear(allocated_mask); + goto retry; } - } - channel->target_cpu = cur_cpu; - channel->target_vp = hv_cpu_number_to_vp_number(cur_cpu); + target_cpu = cpumask_first(available_mask); + cpumask_set_cpu(target_cpu, allocated_mask); - spin_unlock(&bind_channel_to_cpu_lock); + 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; + u32 message_type, i; /* * CHANNELMSG_UNLOAD_RESPONSE is always delivered to the CPU which was @@ -776,16 +826,35 @@ static void vmbus_wait_for_unload(void) * 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. */ - while (1) { + for (i = 1; i <= UNLOAD_WAIT_LOOPS; i++) { if (completion_done(&vmbus_connection.unload_event)) - break; + goto completed; - for_each_online_cpu(cpu) { + 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; + /* + * In a CoCo VM the hyp_synic_message_page is not allocated + * in hv_synic_alloc(). Instead it is set/cleared in + * hv_hyp_synic_enable_regs() and hv_hyp_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->hyp_synic_message_page; + if (!page_addr) + continue; + msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT; @@ -802,19 +871,31 @@ static void vmbus_wait_for_unload(void) vmbus_signal_eom(msg, message_type); } - mdelay(10); + /* + * 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_online_cpu(cpu) { + 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; + page_addr = hv_cpu->hyp_synic_message_page; + if (!page_addr) + continue; + msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT; msg->header.message_type = HVMSG_NONE; } @@ -828,6 +909,11 @@ 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); } @@ -836,11 +922,14 @@ 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; - init_completion(&vmbus_connection.unload_event); + 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), @@ -856,6 +945,74 @@ void vmbus_initiate_unload(bool crash) vmbus_wait_for_unload(); } +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. * @@ -863,12 +1020,107 @@ void vmbus_initiate_unload(bool crash) static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) { struct vmbus_channel_offer_channel *offer; - struct vmbus_channel *newchannel; + struct vmbus_channel *oldchannel, *newchannel; + size_t offer_sz; + bool co_ring_buffer, co_external_memory; 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; + } + + co_ring_buffer = is_co_ring_buffer(offer); + co_external_memory = is_co_external_memory(offer); + if (!co_ring_buffer && co_external_memory) { + pr_err("Invalid offer relid=%d: the ring buffer isn't encrypted\n", + offer->child_relid); + return; + } + if (co_ring_buffer || co_external_memory) { + if (vmbus_proto_version < VERSION_WIN10_V6_0 || !vmbus_is_confidential()) { + pr_err("Invalid offer relid=%d: no support for confidential VMBus\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); + mutex_unlock(&vmbus_connection.channel_mutex); + return; + } + /* Allocate the channel object and save this offer. */ newchannel = alloc_channel(); if (!newchannel) { @@ -877,26 +1129,24 @@ static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) pr_err("Unable to allocate channel object\n"); return; } + newchannel->co_ring_buffer = co_ring_buffer; + newchannel->co_external_memory = co_external_memory; - /* - * Setup state for signalling the host. - */ - newchannel->sig_event = VMBUS_EVENT_CONNECTION_ID; - - if (vmbus_proto_version != VERSION_WS2008) { - newchannel->is_dedicated_interrupt = - (offer->is_dedicated_interrupt != 0); - newchannel->sig_event = offer->connection_id; - } - - memcpy(&newchannel->offermsg, offer, - sizeof(struct vmbus_channel_offer_channel)); - newchannel->monitor_grp = (u8)offer->monitorid / 32; - newchannel->monitor_bit = (u8)offer->monitorid % 32; + 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. * @@ -907,6 +1157,7 @@ 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; @@ -918,11 +1169,22 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) * 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. Given that we handle these - * work elements on the same CPU, this is possible only - * in the case of preemption. In any case wait here - * until the offer processing has moved beyond the - * point where the channel is discoverable. + * 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) { @@ -935,6 +1197,18 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) 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) { @@ -946,6 +1220,8 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) 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. @@ -971,6 +1247,10 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) 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; } /* @@ -982,8 +1262,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) vmbus_device_unregister(channel->device_obj); put_device(dev); } - } - if (channel->primary_channel != NULL) { + } else if (channel->primary_channel != NULL) { /* * Sub-channel is being rescinded. Following is the channel * close sequence when initiated from the driveri (refer to @@ -1003,6 +1282,11 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) } 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) @@ -1020,13 +1304,28 @@ EXPORT_SYMBOL_GPL(vmbus_hvsock_device_unregister); /* * vmbus_onoffers_delivered - - * This is invoked when all offers have been delivered. + * The CHANNELMSG_ALLOFFERS_DELIVERED message arrives after all + * boot-time offers are delivered. A boot-time offer is for the primary + * channel for any virtual hardware configured in the VM at the time it boots. + * Boot-time offers include offers for physical devices assigned to the VM + * via Hyper-V's Discrete Device Assignment (DDA) functionality that are + * handled as virtual PCI devices in Linux (e.g., NVMe devices and GPUs). + * Boot-time offers do not include offers for VMBus sub-channels. Because + * devices can be hot-added to the VM after it is booted, additional channel + * offers that aren't boot-time offers can be received at any time after the + * all-offers-delivered message. * - * Nothing to do here. + * SR-IOV NIC Virtual Functions (VFs) assigned to a VM are not considered + * to be assigned to the VM at boot-time, and offers for VFs may occur after + * the all-offers-delivered message. VFs are optional accelerators to the + * synthetic VMBus NIC and are effectively hot-added only after the VMBus + * NIC channel is opened (once it knows the guest can support it, via the + * sriov bit in the netvsc protocol). */ static void vmbus_onoffers_delivered( struct vmbus_channel_message_header *hdr) { + complete(&vmbus_connection.all_offers_delivered_event); } /* @@ -1125,6 +1424,46 @@ static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr) } /* + * 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. @@ -1211,28 +1550,38 @@ static void vmbus_onversion_response( /* Channel message dispatch table */ const struct vmbus_channel_message_table_entry channel_message_table[CHANNELMSG_COUNT] = { - { CHANNELMSG_INVALID, 0, NULL }, - { CHANNELMSG_OFFERCHANNEL, 0, vmbus_onoffer }, - { CHANNELMSG_RESCIND_CHANNELOFFER, 0, vmbus_onoffer_rescind }, - { CHANNELMSG_REQUESTOFFERS, 0, NULL }, - { CHANNELMSG_ALLOFFERS_DELIVERED, 1, vmbus_onoffers_delivered }, - { CHANNELMSG_OPENCHANNEL, 0, NULL }, - { CHANNELMSG_OPENCHANNEL_RESULT, 1, vmbus_onopen_result }, - { CHANNELMSG_CLOSECHANNEL, 0, NULL }, - { CHANNELMSG_GPADL_HEADER, 0, NULL }, - { CHANNELMSG_GPADL_BODY, 0, NULL }, - { CHANNELMSG_GPADL_CREATED, 1, vmbus_ongpadl_created }, - { CHANNELMSG_GPADL_TEARDOWN, 0, NULL }, - { CHANNELMSG_GPADL_TORNDOWN, 1, vmbus_ongpadl_torndown }, - { CHANNELMSG_RELID_RELEASED, 0, NULL }, - { CHANNELMSG_INITIATE_CONTACT, 0, NULL }, - { CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response }, - { CHANNELMSG_UNLOAD, 0, NULL }, - { CHANNELMSG_UNLOAD_RESPONSE, 1, vmbus_unload_response }, - { CHANNELMSG_18, 0, NULL }, - { CHANNELMSG_19, 0, NULL }, - { CHANNELMSG_20, 0, NULL }, - { CHANNELMSG_TL_CONNECT_REQUEST, 0, NULL }, + { 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)}, }; /* @@ -1240,33 +1589,20 @@ channel_message_table[CHANNELMSG_COUNT] = { * * This is invoked in the vmbus worker thread context. */ -void vmbus_onmessage(void *context) +void vmbus_onmessage(struct vmbus_channel_message_header *hdr) { - struct hv_message *msg = context; - struct vmbus_channel_message_header *hdr; - int size; - - hdr = (struct vmbus_channel_message_header *)msg->u.payload; - size = msg->header.payload_size; - trace_vmbus_on_message(hdr); - if (hdr->msgtype >= CHANNELMSG_COUNT) { - pr_err("Received invalid channel message type %d size %d\n", - hdr->msgtype, size); - print_hex_dump_bytes("", DUMP_PREFIX_NONE, - (unsigned char *)msg->u.payload, size); - return; - } - - if (channel_message_table[hdr->msgtype].message_handler) - channel_message_table[hdr->msgtype].message_handler(hdr); - else - pr_err("Unhandled channel message type %d\n", hdr->msgtype); + /* + * 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. + * vmbus_request_offers - Send a request to get all our pending offers + * and wait for all boot-time offers to arrive. */ int vmbus_request_offers(void) { @@ -1274,7 +1610,7 @@ int vmbus_request_offers(void) struct vmbus_channel_msginfo *msginfo; int ret; - msginfo = kmalloc(sizeof(*msginfo) + + msginfo = kzalloc(sizeof(*msginfo) + sizeof(struct vmbus_channel_message_header), GFP_KERNEL); if (!msginfo) @@ -1284,6 +1620,10 @@ int vmbus_request_offers(void) msg->msgtype = CHANNELMSG_REQUESTOFFERS; + /* + * This REQUESTOFFERS message will result in the host sending an all + * offers delivered message after all the boot-time offers are sent. + */ ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_message_header), true); @@ -1295,25 +1635,33 @@ int vmbus_request_offers(void) goto cleanup; } -cleanup: - kfree(msginfo); - - return ret; -} + /* + * Wait for the host to send all boot-time offers. + * Keeping it as a best-effort mechanism, where a warning is + * printed if a timeout occurs, and execution is resumed. + */ + if (!wait_for_completion_timeout(&vmbus_connection.all_offers_delivered_event, + secs_to_jiffies(60))) { + pr_warn("timed out waiting for all boot-time offers to be delivered.\n"); + } -static void invoke_sc_cb(struct vmbus_channel *primary_channel) -{ - struct list_head *cur, *tmp; - struct vmbus_channel *cur_channel; + /* + * Flush handling of offer messages (which may initiate work on + * other work queues). + */ + flush_workqueue(vmbus_connection.work_queue); - if (primary_channel->sc_creation_callback == NULL) - return; + /* + * Flush workqueue for processing the incoming offers. Subchannel + * offers and their processing can happen later, so there is no need to + * flush that workqueue here. + */ + flush_workqueue(vmbus_connection.handle_primary_chan_wq); - list_for_each_safe(cur, tmp, &primary_channel->sc_list) { - cur_channel = list_entry(cur, struct vmbus_channel, sc_list); +cleanup: + kfree(msginfo); - primary_channel->sc_creation_callback(cur_channel); - } + return ret; } void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel, @@ -1323,25 +1671,6 @@ void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel, } EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback); -bool vmbus_are_subchannels_present(struct vmbus_channel *primary) -{ - bool ret; - - ret = !list_empty(&primary->sc_list); - - if (ret) { - /* - * Invoke the callback on sub-channel creation. - * This will present a uniform interface to the - * clients. - */ - invoke_sc_cb(primary); - } - - return ret; -} -EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present); - void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel, void (*chn_rescind_cb)(struct vmbus_channel *)) { |