diff options
Diffstat (limited to 'drivers/hv/channel_mgmt.c')
| -rw-r--r-- | drivers/hv/channel_mgmt.c | 161 |
1 files changed, 144 insertions, 17 deletions
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index addcef50df7a..8eb167540b4f 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -407,7 +407,15 @@ void hv_process_channel_removal(struct vmbus_channel *channel) cpumask_clear_cpu(channel->target_cpu, &primary_channel->alloced_cpus_in_node); - 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offermsg.child_relid); + /* + * Upon suspend, an in-use hv_sock channel is marked as "rescinded" and + * the relid is invalidated; after hibernation, when the user-space app + * destroys the channel, the relid is INVALID_RELID, and in this case + * it's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); } @@ -545,6 +553,10 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel) mutex_lock(&vmbus_connection.channel_mutex); + /* 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. @@ -847,6 +859,67 @@ void vmbus_initiate_unload(bool crash) 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; + + if (vmbus_proto_version != VERSION_WS2008) { + 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; +} + +/* + * 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; +} + /* * vmbus_onoffer - Handler for channel offers from vmbus in parent partition. * @@ -854,12 +927,58 @@ 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; offer = (struct vmbus_channel_offer_channel *)hdr; trace_vmbus_onoffer(offer); + oldchannel = find_primary_channel_by_offer(offer); + + if (oldchannel != NULL) { + atomic_dec(&vmbus_connection.offer_in_progress); + + /* + * 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. + */ + + 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) { + check_ready_for_resume_event(); + return; + } + + /* + * 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); + + check_ready_for_resume_event(); + + return; + } + /* Allocate the channel object and save this offer. */ newchannel = alloc_channel(); if (!newchannel) { @@ -869,25 +988,21 @@ static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) return; } - /* - * 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. * @@ -898,6 +1013,7 @@ 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; @@ -937,6 +1053,8 @@ 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. @@ -962,6 +1080,10 @@ 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; } /* @@ -994,6 +1116,11 @@ 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) |