cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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irq_comm.c (11426B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * irq_comm.c: Common API for in kernel interrupt controller
      4 * Copyright (c) 2007, Intel Corporation.
      5 *
      6 * Authors:
      7 *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
      8 *
      9 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
     10 */
     11
     12#include <linux/kvm_host.h>
     13#include <linux/slab.h>
     14#include <linux/export.h>
     15#include <linux/rculist.h>
     16
     17#include <trace/events/kvm.h>
     18
     19#include "irq.h"
     20
     21#include "ioapic.h"
     22
     23#include "lapic.h"
     24
     25#include "hyperv.h"
     26#include "x86.h"
     27#include "xen.h"
     28
     29static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
     30			   struct kvm *kvm, int irq_source_id, int level,
     31			   bool line_status)
     32{
     33	struct kvm_pic *pic = kvm->arch.vpic;
     34	return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
     35}
     36
     37static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
     38			      struct kvm *kvm, int irq_source_id, int level,
     39			      bool line_status)
     40{
     41	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
     42	return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level,
     43				line_status);
     44}
     45
     46int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
     47		struct kvm_lapic_irq *irq, struct dest_map *dest_map)
     48{
     49	int r = -1;
     50	struct kvm_vcpu *vcpu, *lowest = NULL;
     51	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
     52	unsigned int dest_vcpus = 0;
     53
     54	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
     55		return r;
     56
     57	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
     58	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
     59		printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
     60		irq->delivery_mode = APIC_DM_FIXED;
     61	}
     62
     63	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
     64
     65	kvm_for_each_vcpu(i, vcpu, kvm) {
     66		if (!kvm_apic_present(vcpu))
     67			continue;
     68
     69		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
     70					irq->dest_id, irq->dest_mode))
     71			continue;
     72
     73		if (!kvm_lowest_prio_delivery(irq)) {
     74			if (r < 0)
     75				r = 0;
     76			r += kvm_apic_set_irq(vcpu, irq, dest_map);
     77		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
     78			if (!kvm_vector_hashing_enabled()) {
     79				if (!lowest)
     80					lowest = vcpu;
     81				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
     82					lowest = vcpu;
     83			} else {
     84				__set_bit(i, dest_vcpu_bitmap);
     85				dest_vcpus++;
     86			}
     87		}
     88	}
     89
     90	if (dest_vcpus != 0) {
     91		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
     92					dest_vcpu_bitmap, KVM_MAX_VCPUS);
     93
     94		lowest = kvm_get_vcpu(kvm, idx);
     95	}
     96
     97	if (lowest)
     98		r = kvm_apic_set_irq(lowest, irq, dest_map);
     99
    100	return r;
    101}
    102
    103void kvm_set_msi_irq(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
    104		     struct kvm_lapic_irq *irq)
    105{
    106	struct msi_msg msg = { .address_lo = e->msi.address_lo,
    107			       .address_hi = e->msi.address_hi,
    108			       .data = e->msi.data };
    109
    110	trace_kvm_msi_set_irq(msg.address_lo | (kvm->arch.x2apic_format ?
    111			      (u64)msg.address_hi << 32 : 0), msg.data);
    112
    113	irq->dest_id = x86_msi_msg_get_destid(&msg, kvm->arch.x2apic_format);
    114	irq->vector = msg.arch_data.vector;
    115	irq->dest_mode = kvm_lapic_irq_dest_mode(msg.arch_addr_lo.dest_mode_logical);
    116	irq->trig_mode = msg.arch_data.is_level;
    117	irq->delivery_mode = msg.arch_data.delivery_mode << 8;
    118	irq->msi_redir_hint = msg.arch_addr_lo.redirect_hint;
    119	irq->level = 1;
    120	irq->shorthand = APIC_DEST_NOSHORT;
    121}
    122EXPORT_SYMBOL_GPL(kvm_set_msi_irq);
    123
    124static inline bool kvm_msi_route_invalid(struct kvm *kvm,
    125		struct kvm_kernel_irq_routing_entry *e)
    126{
    127	return kvm->arch.x2apic_format && (e->msi.address_hi & 0xff);
    128}
    129
    130int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
    131		struct kvm *kvm, int irq_source_id, int level, bool line_status)
    132{
    133	struct kvm_lapic_irq irq;
    134
    135	if (kvm_msi_route_invalid(kvm, e))
    136		return -EINVAL;
    137
    138	if (!level)
    139		return -1;
    140
    141	kvm_set_msi_irq(kvm, e, &irq);
    142
    143	return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
    144}
    145
    146
    147static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
    148		    struct kvm *kvm, int irq_source_id, int level,
    149		    bool line_status)
    150{
    151	if (!level)
    152		return -1;
    153
    154	return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
    155}
    156
    157int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
    158			      struct kvm *kvm, int irq_source_id, int level,
    159			      bool line_status)
    160{
    161	struct kvm_lapic_irq irq;
    162	int r;
    163
    164	switch (e->type) {
    165	case KVM_IRQ_ROUTING_HV_SINT:
    166		return kvm_hv_set_sint(e, kvm, irq_source_id, level,
    167				       line_status);
    168
    169	case KVM_IRQ_ROUTING_MSI:
    170		if (kvm_msi_route_invalid(kvm, e))
    171			return -EINVAL;
    172
    173		kvm_set_msi_irq(kvm, e, &irq);
    174
    175		if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
    176			return r;
    177		break;
    178
    179#ifdef CONFIG_KVM_XEN
    180	case KVM_IRQ_ROUTING_XEN_EVTCHN:
    181		if (!level)
    182			return -1;
    183
    184		return kvm_xen_set_evtchn_fast(&e->xen_evtchn, kvm);
    185#endif
    186	default:
    187		break;
    188	}
    189
    190	return -EWOULDBLOCK;
    191}
    192
    193int kvm_request_irq_source_id(struct kvm *kvm)
    194{
    195	unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
    196	int irq_source_id;
    197
    198	mutex_lock(&kvm->irq_lock);
    199	irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
    200
    201	if (irq_source_id >= BITS_PER_LONG) {
    202		printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
    203		irq_source_id = -EFAULT;
    204		goto unlock;
    205	}
    206
    207	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
    208	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
    209	set_bit(irq_source_id, bitmap);
    210unlock:
    211	mutex_unlock(&kvm->irq_lock);
    212
    213	return irq_source_id;
    214}
    215
    216void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
    217{
    218	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
    219	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
    220
    221	mutex_lock(&kvm->irq_lock);
    222	if (irq_source_id < 0 ||
    223	    irq_source_id >= BITS_PER_LONG) {
    224		printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
    225		goto unlock;
    226	}
    227	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
    228	if (!irqchip_kernel(kvm))
    229		goto unlock;
    230
    231	kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
    232	kvm_pic_clear_all(kvm->arch.vpic, irq_source_id);
    233unlock:
    234	mutex_unlock(&kvm->irq_lock);
    235}
    236
    237void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
    238				    struct kvm_irq_mask_notifier *kimn)
    239{
    240	mutex_lock(&kvm->irq_lock);
    241	kimn->irq = irq;
    242	hlist_add_head_rcu(&kimn->link, &kvm->arch.mask_notifier_list);
    243	mutex_unlock(&kvm->irq_lock);
    244}
    245
    246void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
    247				      struct kvm_irq_mask_notifier *kimn)
    248{
    249	mutex_lock(&kvm->irq_lock);
    250	hlist_del_rcu(&kimn->link);
    251	mutex_unlock(&kvm->irq_lock);
    252	synchronize_srcu(&kvm->irq_srcu);
    253}
    254
    255void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
    256			     bool mask)
    257{
    258	struct kvm_irq_mask_notifier *kimn;
    259	int idx, gsi;
    260
    261	idx = srcu_read_lock(&kvm->irq_srcu);
    262	gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin);
    263	if (gsi != -1)
    264		hlist_for_each_entry_rcu(kimn, &kvm->arch.mask_notifier_list, link)
    265			if (kimn->irq == gsi)
    266				kimn->func(kimn, mask);
    267	srcu_read_unlock(&kvm->irq_srcu, idx);
    268}
    269
    270bool kvm_arch_can_set_irq_routing(struct kvm *kvm)
    271{
    272	return irqchip_in_kernel(kvm);
    273}
    274
    275int kvm_set_routing_entry(struct kvm *kvm,
    276			  struct kvm_kernel_irq_routing_entry *e,
    277			  const struct kvm_irq_routing_entry *ue)
    278{
    279	/* We can't check irqchip_in_kernel() here as some callers are
    280	 * currently initializing the irqchip. Other callers should therefore
    281	 * check kvm_arch_can_set_irq_routing() before calling this function.
    282	 */
    283	switch (ue->type) {
    284	case KVM_IRQ_ROUTING_IRQCHIP:
    285		if (irqchip_split(kvm))
    286			return -EINVAL;
    287		e->irqchip.pin = ue->u.irqchip.pin;
    288		switch (ue->u.irqchip.irqchip) {
    289		case KVM_IRQCHIP_PIC_SLAVE:
    290			e->irqchip.pin += PIC_NUM_PINS / 2;
    291			fallthrough;
    292		case KVM_IRQCHIP_PIC_MASTER:
    293			if (ue->u.irqchip.pin >= PIC_NUM_PINS / 2)
    294				return -EINVAL;
    295			e->set = kvm_set_pic_irq;
    296			break;
    297		case KVM_IRQCHIP_IOAPIC:
    298			if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS)
    299				return -EINVAL;
    300			e->set = kvm_set_ioapic_irq;
    301			break;
    302		default:
    303			return -EINVAL;
    304		}
    305		e->irqchip.irqchip = ue->u.irqchip.irqchip;
    306		break;
    307	case KVM_IRQ_ROUTING_MSI:
    308		e->set = kvm_set_msi;
    309		e->msi.address_lo = ue->u.msi.address_lo;
    310		e->msi.address_hi = ue->u.msi.address_hi;
    311		e->msi.data = ue->u.msi.data;
    312
    313		if (kvm_msi_route_invalid(kvm, e))
    314			return -EINVAL;
    315		break;
    316	case KVM_IRQ_ROUTING_HV_SINT:
    317		e->set = kvm_hv_set_sint;
    318		e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
    319		e->hv_sint.sint = ue->u.hv_sint.sint;
    320		break;
    321#ifdef CONFIG_KVM_XEN
    322	case KVM_IRQ_ROUTING_XEN_EVTCHN:
    323		return kvm_xen_setup_evtchn(kvm, e, ue);
    324#endif
    325	default:
    326		return -EINVAL;
    327	}
    328
    329	return 0;
    330}
    331
    332bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
    333			     struct kvm_vcpu **dest_vcpu)
    334{
    335	int r = 0;
    336	unsigned long i;
    337	struct kvm_vcpu *vcpu;
    338
    339	if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))
    340		return true;
    341
    342	kvm_for_each_vcpu(i, vcpu, kvm) {
    343		if (!kvm_apic_present(vcpu))
    344			continue;
    345
    346		if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,
    347					irq->dest_id, irq->dest_mode))
    348			continue;
    349
    350		if (++r == 2)
    351			return false;
    352
    353		*dest_vcpu = vcpu;
    354	}
    355
    356	return r == 1;
    357}
    358EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);
    359
    360#define IOAPIC_ROUTING_ENTRY(irq) \
    361	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
    362	  .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
    363#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
    364
    365#define PIC_ROUTING_ENTRY(irq) \
    366	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
    367	  .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } }
    368#define ROUTING_ENTRY2(irq) \
    369	IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
    370
    371static const struct kvm_irq_routing_entry default_routing[] = {
    372	ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
    373	ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
    374	ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
    375	ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
    376	ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
    377	ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
    378	ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
    379	ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
    380	ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
    381	ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
    382	ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
    383	ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
    384};
    385
    386int kvm_setup_default_irq_routing(struct kvm *kvm)
    387{
    388	return kvm_set_irq_routing(kvm, default_routing,
    389				   ARRAY_SIZE(default_routing), 0);
    390}
    391
    392static const struct kvm_irq_routing_entry empty_routing[] = {};
    393
    394int kvm_setup_empty_irq_routing(struct kvm *kvm)
    395{
    396	return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
    397}
    398
    399void kvm_arch_post_irq_routing_update(struct kvm *kvm)
    400{
    401	if (!irqchip_split(kvm))
    402		return;
    403	kvm_make_scan_ioapic_request(kvm);
    404}
    405
    406void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
    407			    ulong *ioapic_handled_vectors)
    408{
    409	struct kvm *kvm = vcpu->kvm;
    410	struct kvm_kernel_irq_routing_entry *entry;
    411	struct kvm_irq_routing_table *table;
    412	u32 i, nr_ioapic_pins;
    413	int idx;
    414
    415	idx = srcu_read_lock(&kvm->irq_srcu);
    416	table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
    417	nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
    418			       kvm->arch.nr_reserved_ioapic_pins);
    419	for (i = 0; i < nr_ioapic_pins; ++i) {
    420		hlist_for_each_entry(entry, &table->map[i], link) {
    421			struct kvm_lapic_irq irq;
    422
    423			if (entry->type != KVM_IRQ_ROUTING_MSI)
    424				continue;
    425
    426			kvm_set_msi_irq(vcpu->kvm, entry, &irq);
    427
    428			if (irq.trig_mode &&
    429			    kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT,
    430						irq.dest_id, irq.dest_mode))
    431				__set_bit(irq.vector, ioapic_handled_vectors);
    432		}
    433	}
    434	srcu_read_unlock(&kvm->irq_srcu, idx);
    435}
    436
    437void kvm_arch_irq_routing_update(struct kvm *kvm)
    438{
    439	kvm_hv_irq_routing_update(kvm);
    440}