// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2009, Microsoft Corporation. * * Authors: * Haiyang Zhang <haiyangz@microsoft.com> * Hank Janssen <hjanssen@microsoft.com> */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/kernel.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/vmalloc.h> #include <linux/hyperv.h> #include <linux/version.h> #include <linux/random.h> #include <linux/clockchips.h> #include <clocksource/hyperv_timer.h> #include <asm/mshyperv.h> #include "hyperv_vmbus.h" /* The one and only */ struct hv_context hv_context; /* * hv_init - Main initialization routine. * * This routine must be called before any other routines in here are called */ int hv_init(void) { hv_context.cpu_context = alloc_percpu(struct hv_per_cpu_context); if (!hv_context.cpu_context) return -ENOMEM; return 0; } /* * hv_post_message - Post a message using the hypervisor message IPC. * * This involves a hypercall. */ int hv_post_message(union hv_connection_id connection_id, enum hv_message_type message_type, void *payload, size_t payload_size) { struct hv_input_post_message *aligned_msg; struct hv_per_cpu_context *hv_cpu; u64 status; if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) return -EMSGSIZE; hv_cpu = get_cpu_ptr(hv_context.cpu_context); aligned_msg = hv_cpu->post_msg_page; aligned_msg->connectionid = connection_id; aligned_msg->reserved = 0; aligned_msg->message_type = message_type; aligned_msg->payload_size = payload_size; memcpy((void *)aligned_msg->payload, payload, payload_size); status = hv_do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL); /* Preemption must remain disabled until after the hypercall * so some other thread can't get scheduled onto this cpu and * corrupt the per-cpu post_msg_page */ put_cpu_ptr(hv_cpu); return status & 0xFFFF; } int hv_synic_alloc(void) { int cpu; struct hv_per_cpu_context *hv_cpu; /* * First, zero all per-cpu memory areas so hv_synic_free() can * detect what memory has been allocated and cleanup properly * after any failures. */ for_each_present_cpu(cpu) { hv_cpu = per_cpu_ptr(hv_context.cpu_context, cpu); memset(hv_cpu, 0, sizeof(*hv_cpu)); } hv_context.hv_numa_map = kcalloc(nr_node_ids, sizeof(struct cpumask), GFP_KERNEL); if (hv_context.hv_numa_map == NULL) { pr_err("Unable to allocate NUMA map\n"); goto err; } for_each_present_cpu(cpu) { hv_cpu = per_cpu_ptr(hv_context.cpu_context, cpu); tasklet_init(&hv_cpu->msg_dpc, vmbus_on_msg_dpc, (unsigned long) hv_cpu); hv_cpu->synic_message_page = (void *)get_zeroed_page(GFP_ATOMIC); if (hv_cpu->synic_message_page == NULL) { pr_err("Unable to allocate SYNIC message page\n"); goto err; } hv_cpu->synic_event_page = (void *)get_zeroed_page(GFP_ATOMIC); if (hv_cpu->synic_event_page == NULL) { pr_err("Unable to allocate SYNIC event page\n"); goto err; } hv_cpu->post_msg_page = (void *)get_zeroed_page(GFP_ATOMIC); if (hv_cpu->post_msg_page == NULL) { pr_err("Unable to allocate post msg page\n"); goto err; } INIT_LIST_HEAD(&hv_cpu->chan_list); } return 0; err: /* * Any memory allocations that succeeded will be freed when * the caller cleans up by calling hv_synic_free() */ return -ENOMEM; } void hv_synic_free(void) { int cpu; for_each_present_cpu(cpu) { struct hv_per_cpu_context *hv_cpu = per_cpu_ptr(hv_context.cpu_context, cpu); free_page((unsigned long)hv_cpu->synic_event_page); free_page((unsigned long)hv_cpu->synic_message_page); free_page((unsigned long)hv_cpu->post_msg_page); } kfree(hv_context.hv_numa_map); } /* * hv_synic_init - Initialize the Synthetic Interrupt Controller. * * If it is already initialized by another entity (ie x2v shim), we need to * retrieve the initialized message and event pages. Otherwise, we create and * initialize the message and event pages. */ int hv_synic_init(unsigned int cpu) { struct hv_per_cpu_context *hv_cpu = per_cpu_ptr(hv_context.cpu_context, cpu); union hv_synic_simp simp; union hv_synic_siefp siefp; union hv_synic_sint shared_sint; union hv_synic_scontrol sctrl; /* Setup the Synic's message page */ hv_get_simp(simp.as_uint64); simp.simp_enabled = 1; simp.base_simp_gpa = virt_to_phys(hv_cpu->synic_message_page) >> PAGE_SHIFT; hv_set_simp(simp.as_uint64); /* Setup the Synic's event page */ hv_get_siefp(siefp.as_uint64); siefp.siefp_enabled = 1; siefp.base_siefp_gpa = virt_to_phys(hv_cpu->synic_event_page) >> PAGE_SHIFT; hv_set_siefp(siefp.as_uint64); /* Setup the shared SINT. */ hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR; shared_sint.masked = false; if (ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED) shared_sint.auto_eoi = false; else shared_sint.auto_eoi = true; hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); /* Enable the global synic bit */ hv_get_synic_state(sctrl.as_uint64); sctrl.enable = 1; hv_set_synic_state(sctrl.as_uint64); hv_stimer_init(cpu); return 0; } /* * hv_synic_cleanup - Cleanup routine for hv_synic_init(). */ int hv_synic_cleanup(unsigned int cpu) { union hv_synic_sint shared_sint; union hv_synic_simp simp; union hv_synic_siefp siefp; union hv_synic_scontrol sctrl; struct vmbus_channel *channel, *sc; bool channel_found = false; unsigned long flags; hv_get_synic_state(sctrl.as_uint64); if (sctrl.enable != 1) return -EFAULT; /* * Search for channels which are bound to the CPU we're about to * cleanup. In case we find one and vmbus is still connected we need to * fail, this will effectively prevent CPU offlining. There is no way * we can re-bind channels to different CPUs for now. */ mutex_lock(&vmbus_connection.channel_mutex); list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { if (channel->target_cpu == cpu) { channel_found = true; break; } spin_lock_irqsave(&channel->lock, flags); list_for_each_entry(sc, &channel->sc_list, sc_list) { if (sc->target_cpu == cpu) { channel_found = true; break; } } spin_unlock_irqrestore(&channel->lock, flags); if (channel_found) break; } mutex_unlock(&vmbus_connection.channel_mutex); if (channel_found && vmbus_connection.conn_state == CONNECTED) return -EBUSY; hv_stimer_cleanup(cpu); hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); shared_sint.masked = 1; /* Need to correctly cleanup in the case of SMP!!! */ /* Disable the interrupt */ hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); hv_get_simp(simp.as_uint64); simp.simp_enabled = 0; simp.base_simp_gpa = 0; hv_set_simp(simp.as_uint64); hv_get_siefp(siefp.as_uint64); siefp.siefp_enabled = 0; siefp.base_siefp_gpa = 0; hv_set_siefp(siefp.as_uint64); /* Disable the global synic bit */ sctrl.enable = 0; hv_set_synic_state(sctrl.as_uint64); return 0; }