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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/hv/hv.c | |
parent | Initial commit. (diff) | |
download | linux-430c2fc249ea5c0536abd21c23382884005c9093.tar.xz linux-430c2fc249ea5c0536abd21c23382884005c9093.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hv/hv.c')
-rw-r--r-- | drivers/hv/hv.c | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c new file mode 100644 index 000000000..f202ac7f4 --- /dev/null +++ b/drivers/hv/hv.c @@ -0,0 +1,288 @@ +// 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; + } + } + + 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. + */ +void hv_synic_enable_regs(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) + >> HV_HYP_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) + >> HV_HYP_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 = hv_get_vector(); + shared_sint.masked = false; + shared_sint.auto_eoi = hv_recommend_using_aeoi(); + 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); +} + +int hv_synic_init(unsigned int cpu) +{ + hv_synic_enable_regs(cpu); + + hv_stimer_legacy_init(cpu, VMBUS_MESSAGE_SINT); + + return 0; +} + +/* + * hv_synic_cleanup - Cleanup routine for hv_synic_init(). + */ +void hv_synic_disable_regs(unsigned int cpu) +{ + union hv_synic_sint shared_sint; + union hv_synic_simp simp; + union hv_synic_siefp siefp; + union hv_synic_scontrol sctrl; + + 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 */ + hv_get_synic_state(sctrl.as_uint64); + sctrl.enable = 0; + hv_set_synic_state(sctrl.as_uint64); +} + +int hv_synic_cleanup(unsigned int cpu) +{ + struct vmbus_channel *channel, *sc; + bool channel_found = false; + + /* + * Hyper-V does not provide a way to change the connect CPU once + * it is set; we must prevent the connect CPU from going offline + * while the VM is running normally. But in the panic or kexec() + * path where the vmbus is already disconnected, the CPU must be + * allowed to shut down. + */ + if (cpu == VMBUS_CONNECT_CPU && + vmbus_connection.conn_state == CONNECTED) + return -EBUSY; + + /* + * 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 + * fail; this will effectively prevent CPU offlining. + * + * TODO: Re-bind the channels to different CPUs. + */ + 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; + } + list_for_each_entry(sc, &channel->sc_list, sc_list) { + if (sc->target_cpu == cpu) { + channel_found = true; + break; + } + } + if (channel_found) + break; + } + mutex_unlock(&vmbus_connection.channel_mutex); + + if (channel_found && vmbus_connection.conn_state == CONNECTED) + return -EBUSY; + + hv_stimer_legacy_cleanup(cpu); + + hv_synic_disable_regs(cpu); + + return 0; +} |