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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 /arch/x86/kvm/i8259.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kvm/i8259.c')
-rw-r--r-- | arch/x86/kvm/i8259.c | 655 |
1 files changed, 655 insertions, 0 deletions
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c new file mode 100644 index 000000000..629a09ca9 --- /dev/null +++ b/arch/x86/kvm/i8259.c @@ -0,0 +1,655 @@ +/* + * 8259 interrupt controller emulation + * + * Copyright (c) 2003-2004 Fabrice Bellard + * Copyright (c) 2007 Intel Corporation + * Copyright 2009 Red Hat, Inc. and/or its affiliates. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + * Authors: + * Yaozu (Eddie) Dong <Eddie.dong@intel.com> + * Port from Qemu. + */ +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/bitops.h> +#include "irq.h" + +#include <linux/kvm_host.h> +#include "trace.h" + +#define pr_pic_unimpl(fmt, ...) \ + pr_err_ratelimited("kvm: pic: " fmt, ## __VA_ARGS__) + +static void pic_irq_request(struct kvm *kvm, int level); + +static void pic_lock(struct kvm_pic *s) + __acquires(&s->lock) +{ + spin_lock(&s->lock); +} + +static void pic_unlock(struct kvm_pic *s) + __releases(&s->lock) +{ + bool wakeup = s->wakeup_needed; + struct kvm_vcpu *vcpu; + int i; + + s->wakeup_needed = false; + + spin_unlock(&s->lock); + + if (wakeup) { + kvm_for_each_vcpu(i, vcpu, s->kvm) { + if (kvm_apic_accept_pic_intr(vcpu)) { + kvm_make_request(KVM_REQ_EVENT, vcpu); + kvm_vcpu_kick(vcpu); + return; + } + } + } +} + +static void pic_clear_isr(struct kvm_kpic_state *s, int irq) +{ + s->isr &= ~(1 << irq); + if (s != &s->pics_state->pics[0]) + irq += 8; + /* + * We are dropping lock while calling ack notifiers since ack + * notifier callbacks for assigned devices call into PIC recursively. + * Other interrupt may be delivered to PIC while lock is dropped but + * it should be safe since PIC state is already updated at this stage. + */ + pic_unlock(s->pics_state); + kvm_notify_acked_irq(s->pics_state->kvm, SELECT_PIC(irq), irq); + pic_lock(s->pics_state); +} + +/* + * set irq level. If an edge is detected, then the IRR is set to 1 + */ +static inline int pic_set_irq1(struct kvm_kpic_state *s, int irq, int level) +{ + int mask, ret = 1; + mask = 1 << irq; + if (s->elcr & mask) /* level triggered */ + if (level) { + ret = !(s->irr & mask); + s->irr |= mask; + s->last_irr |= mask; + } else { + s->irr &= ~mask; + s->last_irr &= ~mask; + } + else /* edge triggered */ + if (level) { + if ((s->last_irr & mask) == 0) { + ret = !(s->irr & mask); + s->irr |= mask; + } + s->last_irr |= mask; + } else + s->last_irr &= ~mask; + + return (s->imr & mask) ? -1 : ret; +} + +/* + * return the highest priority found in mask (highest = smallest + * number). Return 8 if no irq + */ +static inline int get_priority(struct kvm_kpic_state *s, int mask) +{ + int priority; + if (mask == 0) + return 8; + priority = 0; + while ((mask & (1 << ((priority + s->priority_add) & 7))) == 0) + priority++; + return priority; +} + +/* + * return the pic wanted interrupt. return -1 if none + */ +static int pic_get_irq(struct kvm_kpic_state *s) +{ + int mask, cur_priority, priority; + + mask = s->irr & ~s->imr; + priority = get_priority(s, mask); + if (priority == 8) + return -1; + /* + * compute current priority. If special fully nested mode on the + * master, the IRQ coming from the slave is not taken into account + * for the priority computation. + */ + mask = s->isr; + if (s->special_fully_nested_mode && s == &s->pics_state->pics[0]) + mask &= ~(1 << 2); + cur_priority = get_priority(s, mask); + if (priority < cur_priority) + /* + * higher priority found: an irq should be generated + */ + return (priority + s->priority_add) & 7; + else + return -1; +} + +/* + * raise irq to CPU if necessary. must be called every time the active + * irq may change + */ +static void pic_update_irq(struct kvm_pic *s) +{ + int irq2, irq; + + irq2 = pic_get_irq(&s->pics[1]); + if (irq2 >= 0) { + /* + * if irq request by slave pic, signal master PIC + */ + pic_set_irq1(&s->pics[0], 2, 1); + pic_set_irq1(&s->pics[0], 2, 0); + } + irq = pic_get_irq(&s->pics[0]); + pic_irq_request(s->kvm, irq >= 0); +} + +void kvm_pic_update_irq(struct kvm_pic *s) +{ + pic_lock(s); + pic_update_irq(s); + pic_unlock(s); +} + +int kvm_pic_set_irq(struct kvm_pic *s, int irq, int irq_source_id, int level) +{ + int ret, irq_level; + + BUG_ON(irq < 0 || irq >= PIC_NUM_PINS); + + pic_lock(s); + irq_level = __kvm_irq_line_state(&s->irq_states[irq], + irq_source_id, level); + ret = pic_set_irq1(&s->pics[irq >> 3], irq & 7, irq_level); + pic_update_irq(s); + trace_kvm_pic_set_irq(irq >> 3, irq & 7, s->pics[irq >> 3].elcr, + s->pics[irq >> 3].imr, ret == 0); + pic_unlock(s); + + return ret; +} + +void kvm_pic_clear_all(struct kvm_pic *s, int irq_source_id) +{ + int i; + + pic_lock(s); + for (i = 0; i < PIC_NUM_PINS; i++) + __clear_bit(irq_source_id, &s->irq_states[i]); + pic_unlock(s); +} + +/* + * acknowledge interrupt 'irq' + */ +static inline void pic_intack(struct kvm_kpic_state *s, int irq) +{ + s->isr |= 1 << irq; + /* + * We don't clear a level sensitive interrupt here + */ + if (!(s->elcr & (1 << irq))) + s->irr &= ~(1 << irq); + + if (s->auto_eoi) { + if (s->rotate_on_auto_eoi) + s->priority_add = (irq + 1) & 7; + pic_clear_isr(s, irq); + } + +} + +int kvm_pic_read_irq(struct kvm *kvm) +{ + int irq, irq2, intno; + struct kvm_pic *s = kvm->arch.vpic; + + s->output = 0; + + pic_lock(s); + irq = pic_get_irq(&s->pics[0]); + if (irq >= 0) { + pic_intack(&s->pics[0], irq); + if (irq == 2) { + irq2 = pic_get_irq(&s->pics[1]); + if (irq2 >= 0) + pic_intack(&s->pics[1], irq2); + else + /* + * spurious IRQ on slave controller + */ + irq2 = 7; + intno = s->pics[1].irq_base + irq2; + irq = irq2 + 8; + } else + intno = s->pics[0].irq_base + irq; + } else { + /* + * spurious IRQ on host controller + */ + irq = 7; + intno = s->pics[0].irq_base + irq; + } + pic_update_irq(s); + pic_unlock(s); + + return intno; +} + +static void kvm_pic_reset(struct kvm_kpic_state *s) +{ + int irq, i; + struct kvm_vcpu *vcpu; + u8 edge_irr = s->irr & ~s->elcr; + bool found = false; + + s->last_irr = 0; + s->irr &= s->elcr; + s->imr = 0; + s->priority_add = 0; + s->special_mask = 0; + s->read_reg_select = 0; + if (!s->init4) { + s->special_fully_nested_mode = 0; + s->auto_eoi = 0; + } + s->init_state = 1; + + kvm_for_each_vcpu(i, vcpu, s->pics_state->kvm) + if (kvm_apic_accept_pic_intr(vcpu)) { + found = true; + break; + } + + + if (!found) + return; + + for (irq = 0; irq < PIC_NUM_PINS/2; irq++) + if (edge_irr & (1 << irq)) + pic_clear_isr(s, irq); +} + +static void pic_ioport_write(void *opaque, u32 addr, u32 val) +{ + struct kvm_kpic_state *s = opaque; + int priority, cmd, irq; + + addr &= 1; + if (addr == 0) { + if (val & 0x10) { + s->init4 = val & 1; + if (val & 0x02) + pr_pic_unimpl("single mode not supported"); + if (val & 0x08) + pr_pic_unimpl( + "level sensitive irq not supported"); + kvm_pic_reset(s); + } else if (val & 0x08) { + if (val & 0x04) + s->poll = 1; + if (val & 0x02) + s->read_reg_select = val & 1; + if (val & 0x40) + s->special_mask = (val >> 5) & 1; + } else { + cmd = val >> 5; + switch (cmd) { + case 0: + case 4: + s->rotate_on_auto_eoi = cmd >> 2; + break; + case 1: /* end of interrupt */ + case 5: + priority = get_priority(s, s->isr); + if (priority != 8) { + irq = (priority + s->priority_add) & 7; + if (cmd == 5) + s->priority_add = (irq + 1) & 7; + pic_clear_isr(s, irq); + pic_update_irq(s->pics_state); + } + break; + case 3: + irq = val & 7; + pic_clear_isr(s, irq); + pic_update_irq(s->pics_state); + break; + case 6: + s->priority_add = (val + 1) & 7; + pic_update_irq(s->pics_state); + break; + case 7: + irq = val & 7; + s->priority_add = (irq + 1) & 7; + pic_clear_isr(s, irq); + pic_update_irq(s->pics_state); + break; + default: + break; /* no operation */ + } + } + } else + switch (s->init_state) { + case 0: { /* normal mode */ + u8 imr_diff = s->imr ^ val, + off = (s == &s->pics_state->pics[0]) ? 0 : 8; + s->imr = val; + for (irq = 0; irq < PIC_NUM_PINS/2; irq++) + if (imr_diff & (1 << irq)) + kvm_fire_mask_notifiers( + s->pics_state->kvm, + SELECT_PIC(irq + off), + irq + off, + !!(s->imr & (1 << irq))); + pic_update_irq(s->pics_state); + break; + } + case 1: + s->irq_base = val & 0xf8; + s->init_state = 2; + break; + case 2: + if (s->init4) + s->init_state = 3; + else + s->init_state = 0; + break; + case 3: + s->special_fully_nested_mode = (val >> 4) & 1; + s->auto_eoi = (val >> 1) & 1; + s->init_state = 0; + break; + } +} + +static u32 pic_poll_read(struct kvm_kpic_state *s, u32 addr1) +{ + int ret; + + ret = pic_get_irq(s); + if (ret >= 0) { + if (addr1 >> 7) { + s->pics_state->pics[0].isr &= ~(1 << 2); + s->pics_state->pics[0].irr &= ~(1 << 2); + } + s->irr &= ~(1 << ret); + pic_clear_isr(s, ret); + if (addr1 >> 7 || ret != 2) + pic_update_irq(s->pics_state); + } else { + ret = 0x07; + pic_update_irq(s->pics_state); + } + + return ret; +} + +static u32 pic_ioport_read(void *opaque, u32 addr) +{ + struct kvm_kpic_state *s = opaque; + int ret; + + if (s->poll) { + ret = pic_poll_read(s, addr); + s->poll = 0; + } else + if ((addr & 1) == 0) + if (s->read_reg_select) + ret = s->isr; + else + ret = s->irr; + else + ret = s->imr; + return ret; +} + +static void elcr_ioport_write(void *opaque, u32 addr, u32 val) +{ + struct kvm_kpic_state *s = opaque; + s->elcr = val & s->elcr_mask; +} + +static u32 elcr_ioport_read(void *opaque, u32 addr1) +{ + struct kvm_kpic_state *s = opaque; + return s->elcr; +} + +static int picdev_write(struct kvm_pic *s, + gpa_t addr, int len, const void *val) +{ + unsigned char data = *(unsigned char *)val; + + if (len != 1) { + pr_pic_unimpl("non byte write\n"); + return 0; + } + switch (addr) { + case 0x20: + case 0x21: + pic_lock(s); + pic_ioport_write(&s->pics[0], addr, data); + pic_unlock(s); + break; + case 0xa0: + case 0xa1: + pic_lock(s); + pic_ioport_write(&s->pics[1], addr, data); + pic_unlock(s); + break; + case 0x4d0: + case 0x4d1: + pic_lock(s); + elcr_ioport_write(&s->pics[addr & 1], addr, data); + pic_unlock(s); + break; + default: + return -EOPNOTSUPP; + } + return 0; +} + +static int picdev_read(struct kvm_pic *s, + gpa_t addr, int len, void *val) +{ + unsigned char *data = (unsigned char *)val; + + if (len != 1) { + memset(val, 0, len); + pr_pic_unimpl("non byte read\n"); + return 0; + } + switch (addr) { + case 0x20: + case 0x21: + case 0xa0: + case 0xa1: + pic_lock(s); + *data = pic_ioport_read(&s->pics[addr >> 7], addr); + pic_unlock(s); + break; + case 0x4d0: + case 0x4d1: + pic_lock(s); + *data = elcr_ioport_read(&s->pics[addr & 1], addr); + pic_unlock(s); + break; + default: + return -EOPNOTSUPP; + } + return 0; +} + +static int picdev_master_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev, + gpa_t addr, int len, const void *val) +{ + return picdev_write(container_of(dev, struct kvm_pic, dev_master), + addr, len, val); +} + +static int picdev_master_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev, + gpa_t addr, int len, void *val) +{ + return picdev_read(container_of(dev, struct kvm_pic, dev_master), + addr, len, val); +} + +static int picdev_slave_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev, + gpa_t addr, int len, const void *val) +{ + return picdev_write(container_of(dev, struct kvm_pic, dev_slave), + addr, len, val); +} + +static int picdev_slave_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev, + gpa_t addr, int len, void *val) +{ + return picdev_read(container_of(dev, struct kvm_pic, dev_slave), + addr, len, val); +} + +static int picdev_eclr_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev, + gpa_t addr, int len, const void *val) +{ + return picdev_write(container_of(dev, struct kvm_pic, dev_eclr), + addr, len, val); +} + +static int picdev_eclr_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev, + gpa_t addr, int len, void *val) +{ + return picdev_read(container_of(dev, struct kvm_pic, dev_eclr), + addr, len, val); +} + +/* + * callback when PIC0 irq status changed + */ +static void pic_irq_request(struct kvm *kvm, int level) +{ + struct kvm_pic *s = kvm->arch.vpic; + + if (!s->output) + s->wakeup_needed = true; + s->output = level; +} + +static const struct kvm_io_device_ops picdev_master_ops = { + .read = picdev_master_read, + .write = picdev_master_write, +}; + +static const struct kvm_io_device_ops picdev_slave_ops = { + .read = picdev_slave_read, + .write = picdev_slave_write, +}; + +static const struct kvm_io_device_ops picdev_eclr_ops = { + .read = picdev_eclr_read, + .write = picdev_eclr_write, +}; + +int kvm_pic_init(struct kvm *kvm) +{ + struct kvm_pic *s; + int ret; + + s = kzalloc(sizeof(struct kvm_pic), GFP_KERNEL_ACCOUNT); + if (!s) + return -ENOMEM; + spin_lock_init(&s->lock); + s->kvm = kvm; + s->pics[0].elcr_mask = 0xf8; + s->pics[1].elcr_mask = 0xde; + s->pics[0].pics_state = s; + s->pics[1].pics_state = s; + + /* + * Initialize PIO device + */ + kvm_iodevice_init(&s->dev_master, &picdev_master_ops); + kvm_iodevice_init(&s->dev_slave, &picdev_slave_ops); + kvm_iodevice_init(&s->dev_eclr, &picdev_eclr_ops); + mutex_lock(&kvm->slots_lock); + ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 0x20, 2, + &s->dev_master); + if (ret < 0) + goto fail_unlock; + + ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 0xa0, 2, &s->dev_slave); + if (ret < 0) + goto fail_unreg_2; + + ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 0x4d0, 2, &s->dev_eclr); + if (ret < 0) + goto fail_unreg_1; + + mutex_unlock(&kvm->slots_lock); + + kvm->arch.vpic = s; + + return 0; + +fail_unreg_1: + kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &s->dev_slave); + +fail_unreg_2: + kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &s->dev_master); + +fail_unlock: + mutex_unlock(&kvm->slots_lock); + + kfree(s); + + return ret; +} + +void kvm_pic_destroy(struct kvm *kvm) +{ + struct kvm_pic *vpic = kvm->arch.vpic; + + if (!vpic) + return; + + mutex_lock(&kvm->slots_lock); + kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_master); + kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_slave); + kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_eclr); + mutex_unlock(&kvm->slots_lock); + + kvm->arch.vpic = NULL; + kfree(vpic); +} |