Merge branch 'x86-hyperv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 hyperv updates from Thomas Gleixner:
 "A set of commits to enable APIC enlightenment when running as a guest
  on Microsoft HyperV.

  This accelerates the APIC access with paravirtualization techniques,
  which are called enlightenments on Hyper-V"

* 'x86-hyperv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/Hyper-V/hv_apic: Build the Hyper-V APIC conditionally
  x86/Hyper-V/hv_apic: Include asm/apic.h
  X86/Hyper-V: Consolidate the allocation of the hypercall input page
  X86/Hyper-V: Consolidate code for converting cpumask to vpset
  X86/Hyper-V: Enhanced IPI enlightenment
  X86/Hyper-V: Enable IPI enlightenments
  X86/Hyper-V: Enlighten APIC access
This commit is contained in:
Linus Torvalds 2018-06-04 21:37:30 -07:00
commit 716a685fdb
6 changed files with 368 additions and 72 deletions

View File

@ -1 +1,2 @@
obj-y := hv_init.o mmu.o
obj-y := hv_init.o mmu.o
obj-$(CONFIG_X86_64) += hv_apic.o

256
arch/x86/hyperv/hv_apic.c Normal file
View File

@ -0,0 +1,256 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Hyper-V specific APIC code.
*
* Copyright (C) 2018, Microsoft, Inc.
*
* Author : K. Y. Srinivasan <kys@microsoft.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
*/
#include <linux/types.h>
#include <linux/version.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/clockchips.h>
#include <linux/hyperv.h>
#include <linux/slab.h>
#include <linux/cpuhotplug.h>
#include <asm/hypervisor.h>
#include <asm/mshyperv.h>
#include <asm/apic.h>
static struct apic orig_apic;
static u64 hv_apic_icr_read(void)
{
u64 reg_val;
rdmsrl(HV_X64_MSR_ICR, reg_val);
return reg_val;
}
static void hv_apic_icr_write(u32 low, u32 id)
{
u64 reg_val;
reg_val = SET_APIC_DEST_FIELD(id);
reg_val = reg_val << 32;
reg_val |= low;
wrmsrl(HV_X64_MSR_ICR, reg_val);
}
static u32 hv_apic_read(u32 reg)
{
u32 reg_val, hi;
switch (reg) {
case APIC_EOI:
rdmsr(HV_X64_MSR_EOI, reg_val, hi);
return reg_val;
case APIC_TASKPRI:
rdmsr(HV_X64_MSR_TPR, reg_val, hi);
return reg_val;
default:
return native_apic_mem_read(reg);
}
}
static void hv_apic_write(u32 reg, u32 val)
{
switch (reg) {
case APIC_EOI:
wrmsr(HV_X64_MSR_EOI, val, 0);
break;
case APIC_TASKPRI:
wrmsr(HV_X64_MSR_TPR, val, 0);
break;
default:
native_apic_mem_write(reg, val);
}
}
static void hv_apic_eoi_write(u32 reg, u32 val)
{
wrmsr(HV_X64_MSR_EOI, val, 0);
}
/*
* IPI implementation on Hyper-V.
*/
static bool __send_ipi_mask_ex(const struct cpumask *mask, int vector)
{
struct ipi_arg_ex **arg;
struct ipi_arg_ex *ipi_arg;
unsigned long flags;
int nr_bank = 0;
int ret = 1;
local_irq_save(flags);
arg = (struct ipi_arg_ex **)this_cpu_ptr(hyperv_pcpu_input_arg);
ipi_arg = *arg;
if (unlikely(!ipi_arg))
goto ipi_mask_ex_done;
ipi_arg->vector = vector;
ipi_arg->reserved = 0;
ipi_arg->vp_set.valid_bank_mask = 0;
if (!cpumask_equal(mask, cpu_present_mask)) {
ipi_arg->vp_set.format = HV_GENERIC_SET_SPARSE_4K;
nr_bank = cpumask_to_vpset(&(ipi_arg->vp_set), mask);
}
if (!nr_bank)
ipi_arg->vp_set.format = HV_GENERIC_SET_ALL;
ret = hv_do_rep_hypercall(HVCALL_SEND_IPI_EX, 0, nr_bank,
ipi_arg, NULL);
ipi_mask_ex_done:
local_irq_restore(flags);
return ((ret == 0) ? true : false);
}
static bool __send_ipi_mask(const struct cpumask *mask, int vector)
{
int cur_cpu, vcpu;
struct ipi_arg_non_ex **arg;
struct ipi_arg_non_ex *ipi_arg;
int ret = 1;
unsigned long flags;
if (cpumask_empty(mask))
return true;
if (!hv_hypercall_pg)
return false;
if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
return false;
if ((ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
return __send_ipi_mask_ex(mask, vector);
local_irq_save(flags);
arg = (struct ipi_arg_non_ex **)this_cpu_ptr(hyperv_pcpu_input_arg);
ipi_arg = *arg;
if (unlikely(!ipi_arg))
goto ipi_mask_done;
ipi_arg->vector = vector;
ipi_arg->reserved = 0;
ipi_arg->cpu_mask = 0;
for_each_cpu(cur_cpu, mask) {
vcpu = hv_cpu_number_to_vp_number(cur_cpu);
/*
* This particular version of the IPI hypercall can
* only target upto 64 CPUs.
*/
if (vcpu >= 64)
goto ipi_mask_done;
__set_bit(vcpu, (unsigned long *)&ipi_arg->cpu_mask);
}
ret = hv_do_hypercall(HVCALL_SEND_IPI, ipi_arg, NULL);
ipi_mask_done:
local_irq_restore(flags);
return ((ret == 0) ? true : false);
}
static bool __send_ipi_one(int cpu, int vector)
{
struct cpumask mask = CPU_MASK_NONE;
cpumask_set_cpu(cpu, &mask);
return __send_ipi_mask(&mask, vector);
}
static void hv_send_ipi(int cpu, int vector)
{
if (!__send_ipi_one(cpu, vector))
orig_apic.send_IPI(cpu, vector);
}
static void hv_send_ipi_mask(const struct cpumask *mask, int vector)
{
if (!__send_ipi_mask(mask, vector))
orig_apic.send_IPI_mask(mask, vector);
}
static void hv_send_ipi_mask_allbutself(const struct cpumask *mask, int vector)
{
unsigned int this_cpu = smp_processor_id();
struct cpumask new_mask;
const struct cpumask *local_mask;
cpumask_copy(&new_mask, mask);
cpumask_clear_cpu(this_cpu, &new_mask);
local_mask = &new_mask;
if (!__send_ipi_mask(local_mask, vector))
orig_apic.send_IPI_mask_allbutself(mask, vector);
}
static void hv_send_ipi_allbutself(int vector)
{
hv_send_ipi_mask_allbutself(cpu_online_mask, vector);
}
static void hv_send_ipi_all(int vector)
{
if (!__send_ipi_mask(cpu_online_mask, vector))
orig_apic.send_IPI_all(vector);
}
static void hv_send_ipi_self(int vector)
{
if (!__send_ipi_one(smp_processor_id(), vector))
orig_apic.send_IPI_self(vector);
}
void __init hv_apic_init(void)
{
if (ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) {
if ((ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
pr_info("Hyper-V: Using ext hypercalls for IPI\n");
else
pr_info("Hyper-V: Using IPI hypercalls\n");
/*
* Set the IPI entry points.
*/
orig_apic = *apic;
apic->send_IPI = hv_send_ipi;
apic->send_IPI_mask = hv_send_ipi_mask;
apic->send_IPI_mask_allbutself = hv_send_ipi_mask_allbutself;
apic->send_IPI_allbutself = hv_send_ipi_allbutself;
apic->send_IPI_all = hv_send_ipi_all;
apic->send_IPI_self = hv_send_ipi_self;
}
if (ms_hyperv.hints & HV_X64_APIC_ACCESS_RECOMMENDED) {
pr_info("Hyper-V: Using MSR based APIC access\n");
apic_set_eoi_write(hv_apic_eoi_write);
apic->read = hv_apic_read;
apic->write = hv_apic_write;
apic->icr_write = hv_apic_icr_write;
apic->icr_read = hv_apic_icr_read;
}
}

View File

@ -91,12 +91,19 @@ EXPORT_SYMBOL_GPL(hv_vp_index);
struct hv_vp_assist_page **hv_vp_assist_page;
EXPORT_SYMBOL_GPL(hv_vp_assist_page);
void __percpu **hyperv_pcpu_input_arg;
EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg);
u32 hv_max_vp_index;
static int hv_cpu_init(unsigned int cpu)
{
u64 msr_vp_index;
struct hv_vp_assist_page **hvp = &hv_vp_assist_page[smp_processor_id()];
void **input_arg;
input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
*input_arg = page_address(alloc_page(GFP_KERNEL));
hv_get_vp_index(msr_vp_index);
@ -217,6 +224,16 @@ static int hv_cpu_die(unsigned int cpu)
{
struct hv_reenlightenment_control re_ctrl;
unsigned int new_cpu;
unsigned long flags;
void **input_arg;
void *input_pg = NULL;
local_irq_save(flags);
input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
input_pg = *input_arg;
*input_arg = NULL;
local_irq_restore(flags);
free_page((unsigned long)input_pg);
if (hv_vp_assist_page && hv_vp_assist_page[cpu])
wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, 0);
@ -242,8 +259,9 @@ static int hv_cpu_die(unsigned int cpu)
*
* 1. Setup the hypercall page.
* 2. Register Hyper-V specific clocksource.
* 3. Setup Hyper-V specific APIC entry points.
*/
void hyperv_init(void)
void __init hyperv_init(void)
{
u64 guest_id, required_msrs;
union hv_x64_msr_hypercall_contents hypercall_msr;
@ -259,6 +277,16 @@ void hyperv_init(void)
if ((ms_hyperv.features & required_msrs) != required_msrs)
return;
/*
* Allocate the per-CPU state for the hypercall input arg.
* If this allocation fails, we will not be able to setup
* (per-CPU) hypercall input page and thus this failure is
* fatal on Hyper-V.
*/
hyperv_pcpu_input_arg = alloc_percpu(void *);
BUG_ON(hyperv_pcpu_input_arg == NULL);
/* Allocate percpu VP index */
hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index),
GFP_KERNEL);
@ -296,7 +324,7 @@ void hyperv_init(void)
hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
hyper_alloc_mmu();
hv_apic_init();
/*
* Register Hyper-V specific clocksource.

View File

@ -25,20 +25,13 @@ struct hv_flush_pcpu {
struct hv_flush_pcpu_ex {
u64 address_space;
u64 flags;
struct {
u64 format;
u64 valid_bank_mask;
u64 bank_contents[];
} hv_vp_set;
struct hv_vpset hv_vp_set;
u64 gva_list[];
};
/* Each gva in gva_list encodes up to 4096 pages to flush */
#define HV_TLB_FLUSH_UNIT (4096 * PAGE_SIZE)
static struct hv_flush_pcpu __percpu **pcpu_flush;
static struct hv_flush_pcpu_ex __percpu **pcpu_flush_ex;
/*
* Fills in gva_list starting from offset. Returns the number of items added.
@ -70,41 +63,6 @@ static inline int fill_gva_list(u64 gva_list[], int offset,
return gva_n - offset;
}
/* Return the number of banks in the resulting vp_set */
static inline int cpumask_to_vp_set(struct hv_flush_pcpu_ex *flush,
const struct cpumask *cpus)
{
int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
/* valid_bank_mask can represent up to 64 banks */
if (hv_max_vp_index / 64 >= 64)
return 0;
/*
* Clear all banks up to the maximum possible bank as hv_flush_pcpu_ex
* structs are not cleared between calls, we risk flushing unneeded
* vCPUs otherwise.
*/
for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
flush->hv_vp_set.bank_contents[vcpu_bank] = 0;
/*
* Some banks may end up being empty but this is acceptable.
*/
for_each_cpu(cpu, cpus) {
vcpu = hv_cpu_number_to_vp_number(cpu);
vcpu_bank = vcpu / 64;
vcpu_offset = vcpu % 64;
__set_bit(vcpu_offset, (unsigned long *)
&flush->hv_vp_set.bank_contents[vcpu_bank]);
if (vcpu_bank >= nr_bank)
nr_bank = vcpu_bank + 1;
}
flush->hv_vp_set.valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
return nr_bank;
}
static void hyperv_flush_tlb_others(const struct cpumask *cpus,
const struct flush_tlb_info *info)
{
@ -116,7 +74,7 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus,
trace_hyperv_mmu_flush_tlb_others(cpus, info);
if (!pcpu_flush || !hv_hypercall_pg)
if (!hv_hypercall_pg)
goto do_native;
if (cpumask_empty(cpus))
@ -124,10 +82,8 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus,
local_irq_save(flags);
flush_pcpu = this_cpu_ptr(pcpu_flush);
if (unlikely(!*flush_pcpu))
*flush_pcpu = page_address(alloc_page(GFP_ATOMIC));
flush_pcpu = (struct hv_flush_pcpu **)
this_cpu_ptr(hyperv_pcpu_input_arg);
flush = *flush_pcpu;
@ -203,7 +159,7 @@ static void hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
trace_hyperv_mmu_flush_tlb_others(cpus, info);
if (!pcpu_flush_ex || !hv_hypercall_pg)
if (!hv_hypercall_pg)
goto do_native;
if (cpumask_empty(cpus))
@ -211,10 +167,8 @@ static void hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
local_irq_save(flags);
flush_pcpu = this_cpu_ptr(pcpu_flush_ex);
if (unlikely(!*flush_pcpu))
*flush_pcpu = page_address(alloc_page(GFP_ATOMIC));
flush_pcpu = (struct hv_flush_pcpu_ex **)
this_cpu_ptr(hyperv_pcpu_input_arg);
flush = *flush_pcpu;
@ -239,8 +193,8 @@ static void hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
flush->hv_vp_set.valid_bank_mask = 0;
if (!cpumask_equal(cpus, cpu_present_mask)) {
flush->hv_vp_set.format = HV_GENERIC_SET_SPARCE_4K;
nr_bank = cpumask_to_vp_set(flush, cpus);
flush->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
nr_bank = cpumask_to_vpset(&(flush->hv_vp_set), cpus);
}
if (!nr_bank) {
@ -296,14 +250,3 @@ void hyperv_setup_mmu_ops(void)
pv_mmu_ops.flush_tlb_others = hyperv_flush_tlb_others_ex;
}
}
void hyper_alloc_mmu(void)
{
if (!(ms_hyperv.hints & HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED))
return;
if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
pcpu_flush = alloc_percpu(struct hv_flush_pcpu *);
else
pcpu_flush_ex = alloc_percpu(struct hv_flush_pcpu_ex *);
}

View File

@ -164,6 +164,11 @@
*/
#define HV_X64_DEPRECATING_AEOI_RECOMMENDED (1 << 9)
/*
* Recommend using cluster IPI hypercalls.
*/
#define HV_X64_CLUSTER_IPI_RECOMMENDED (1 << 10)
/* Recommend using the newer ExProcessorMasks interface */
#define HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED (1 << 11)
@ -329,12 +334,17 @@ struct hv_tsc_emulation_status {
#define HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK \
(~((1ull << HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_SHIFT) - 1))
#define HV_IPI_LOW_VECTOR 0x10
#define HV_IPI_HIGH_VECTOR 0xff
/* Declare the various hypercall operations. */
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE 0x0002
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST 0x0003
#define HVCALL_NOTIFY_LONG_SPIN_WAIT 0x0008
#define HVCALL_SEND_IPI 0x000b
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX 0x0013
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX 0x0014
#define HVCALL_SEND_IPI_EX 0x0015
#define HVCALL_POST_MESSAGE 0x005c
#define HVCALL_SIGNAL_EVENT 0x005d
@ -360,7 +370,7 @@ struct hv_tsc_emulation_status {
#define HV_FLUSH_USE_EXTENDED_RANGE_FORMAT BIT(3)
enum HV_GENERIC_SET_FORMAT {
HV_GENERIC_SET_SPARCE_4K,
HV_GENERIC_SET_SPARSE_4K,
HV_GENERIC_SET_ALL,
};
@ -706,4 +716,22 @@ struct hv_enlightened_vmcs {
#define HV_STIMER_AUTOENABLE (1ULL << 3)
#define HV_STIMER_SINT(config) (__u8)(((config) >> 16) & 0x0F)
struct ipi_arg_non_ex {
u32 vector;
u32 reserved;
u64 cpu_mask;
};
struct hv_vpset {
u64 format;
u64 valid_bank_mask;
u64 bank_contents[];
};
struct ipi_arg_ex {
u32 vector;
u32 reserved;
struct hv_vpset vp_set;
};
#endif

View File

@ -122,6 +122,7 @@ static inline void hv_disable_stimer0_percpu_irq(int irq) {}
#if IS_ENABLED(CONFIG_HYPERV)
extern struct clocksource *hyperv_cs;
extern void *hv_hypercall_pg;
extern void __percpu **hyperv_pcpu_input_arg;
static inline u64 hv_do_hypercall(u64 control, void *input, void *output)
{
@ -258,9 +259,41 @@ static inline int hv_cpu_number_to_vp_number(int cpu_number)
return hv_vp_index[cpu_number];
}
void hyperv_init(void);
static inline int cpumask_to_vpset(struct hv_vpset *vpset,
const struct cpumask *cpus)
{
int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
/* valid_bank_mask can represent up to 64 banks */
if (hv_max_vp_index / 64 >= 64)
return 0;
/*
* Clear all banks up to the maximum possible bank as hv_flush_pcpu_ex
* structs are not cleared between calls, we risk flushing unneeded
* vCPUs otherwise.
*/
for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
vpset->bank_contents[vcpu_bank] = 0;
/*
* Some banks may end up being empty but this is acceptable.
*/
for_each_cpu(cpu, cpus) {
vcpu = hv_cpu_number_to_vp_number(cpu);
vcpu_bank = vcpu / 64;
vcpu_offset = vcpu % 64;
__set_bit(vcpu_offset, (unsigned long *)
&vpset->bank_contents[vcpu_bank]);
if (vcpu_bank >= nr_bank)
nr_bank = vcpu_bank + 1;
}
vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
return nr_bank;
}
void __init hyperv_init(void);
void hyperv_setup_mmu_ops(void);
void hyper_alloc_mmu(void);
void hyperv_report_panic(struct pt_regs *regs, long err);
bool hv_is_hyperv_initialized(void);
void hyperv_cleanup(void);
@ -269,6 +302,13 @@ void hyperv_reenlightenment_intr(struct pt_regs *regs);
void set_hv_tscchange_cb(void (*cb)(void));
void clear_hv_tscchange_cb(void);
void hyperv_stop_tsc_emulation(void);
#ifdef CONFIG_X86_64
void hv_apic_init(void);
#else
static inline void hv_apic_init(void) {}
#endif
#else /* CONFIG_HYPERV */
static inline void hyperv_init(void) {}
static inline bool hv_is_hyperv_initialized(void) { return false; }