kernel-fxtec-pro1x/virt/kvm/arm/vgic.c
Andre Przywara fd1d0ddf2a KVM: arm/arm64: check IRQ number on userland injection
When userland injects a SPI via the KVM_IRQ_LINE ioctl we currently
only check it against a fixed limit, which historically is set
to 127. With the new dynamic IRQ allocation the effective limit may
actually be smaller (64).
So when now a malicious or buggy userland injects a SPI in that
range, we spill over on our VGIC bitmaps and bytemaps memory.
I could trigger a host kernel NULL pointer dereference with current
mainline by injecting some bogus IRQ number from a hacked kvmtool:
-----------------
....
DEBUG: kvm_vgic_inject_irq(kvm, cpu=0, irq=114, level=1)
DEBUG: vgic_update_irq_pending(kvm, cpu=0, irq=114, level=1)
DEBUG: IRQ #114 still in the game, writing to bytemap now...
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = ffffffc07652e000
[00000000] *pgd=00000000f658b003, *pud=00000000f658b003, *pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 1053 Comm: lkvm-msi-irqinj Not tainted 4.0.0-rc7+ #3027
Hardware name: FVP Base (DT)
task: ffffffc0774e9680 ti: ffffffc0765a8000 task.ti: ffffffc0765a8000
PC is at kvm_vgic_inject_irq+0x234/0x310
LR is at kvm_vgic_inject_irq+0x30c/0x310
pc : [<ffffffc0000ae0a8>] lr : [<ffffffc0000ae180>] pstate: 80000145
.....

So this patch fixes this by checking the SPI number against the
actual limit. Also we remove the former legacy hard limit of
127 in the ioctl code.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
CC: <stable@vger.kernel.org> # 4.0, 3.19, 3.18
[maz: wrap KVM_ARM_IRQ_GIC_MAX with #ifndef __KERNEL__,
as suggested by Christopher Covington]
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-04-22 15:42:24 +01:00

2176 lines
55 KiB
C

/*
* Copyright (C) 2012 ARM Ltd.
* Author: Marc Zyngier <marc.zyngier@arm.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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/cpu.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/uaccess.h>
#include <linux/irqchip/arm-gic.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
#include <trace/events/kvm.h>
#include <asm/kvm.h>
#include <kvm/iodev.h>
/*
* How the whole thing works (courtesy of Christoffer Dall):
*
* - At any time, the dist->irq_pending_on_cpu is the oracle that knows if
* something is pending on the CPU interface.
* - Interrupts that are pending on the distributor are stored on the
* vgic.irq_pending vgic bitmap (this bitmap is updated by both user land
* ioctls and guest mmio ops, and other in-kernel peripherals such as the
* arch. timers).
* - Every time the bitmap changes, the irq_pending_on_cpu oracle is
* recalculated
* - To calculate the oracle, we need info for each cpu from
* compute_pending_for_cpu, which considers:
* - PPI: dist->irq_pending & dist->irq_enable
* - SPI: dist->irq_pending & dist->irq_enable & dist->irq_spi_target
* - irq_spi_target is a 'formatted' version of the GICD_ITARGETSRn
* registers, stored on each vcpu. We only keep one bit of
* information per interrupt, making sure that only one vcpu can
* accept the interrupt.
* - If any of the above state changes, we must recalculate the oracle.
* - The same is true when injecting an interrupt, except that we only
* consider a single interrupt at a time. The irq_spi_cpu array
* contains the target CPU for each SPI.
*
* The handling of level interrupts adds some extra complexity. We
* need to track when the interrupt has been EOIed, so we can sample
* the 'line' again. This is achieved as such:
*
* - When a level interrupt is moved onto a vcpu, the corresponding
* bit in irq_queued is set. As long as this bit is set, the line
* will be ignored for further interrupts. The interrupt is injected
* into the vcpu with the GICH_LR_EOI bit set (generate a
* maintenance interrupt on EOI).
* - When the interrupt is EOIed, the maintenance interrupt fires,
* and clears the corresponding bit in irq_queued. This allows the
* interrupt line to be sampled again.
* - Note that level-triggered interrupts can also be set to pending from
* writes to GICD_ISPENDRn and lowering the external input line does not
* cause the interrupt to become inactive in such a situation.
* Conversely, writes to GICD_ICPENDRn do not cause the interrupt to become
* inactive as long as the external input line is held high.
*/
#include "vgic.h"
static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu);
static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu);
static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr);
static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr, struct vgic_lr lr_desc);
static const struct vgic_ops *vgic_ops;
static const struct vgic_params *vgic;
static void add_sgi_source(struct kvm_vcpu *vcpu, int irq, int source)
{
vcpu->kvm->arch.vgic.vm_ops.add_sgi_source(vcpu, irq, source);
}
static bool queue_sgi(struct kvm_vcpu *vcpu, int irq)
{
return vcpu->kvm->arch.vgic.vm_ops.queue_sgi(vcpu, irq);
}
int kvm_vgic_map_resources(struct kvm *kvm)
{
return kvm->arch.vgic.vm_ops.map_resources(kvm, vgic);
}
/*
* struct vgic_bitmap contains a bitmap made of unsigned longs, but
* extracts u32s out of them.
*
* This does not work on 64-bit BE systems, because the bitmap access
* will store two consecutive 32-bit words with the higher-addressed
* register's bits at the lower index and the lower-addressed register's
* bits at the higher index.
*
* Therefore, swizzle the register index when accessing the 32-bit word
* registers to access the right register's value.
*/
#if defined(CONFIG_CPU_BIG_ENDIAN) && BITS_PER_LONG == 64
#define REG_OFFSET_SWIZZLE 1
#else
#define REG_OFFSET_SWIZZLE 0
#endif
static int vgic_init_bitmap(struct vgic_bitmap *b, int nr_cpus, int nr_irqs)
{
int nr_longs;
nr_longs = nr_cpus + BITS_TO_LONGS(nr_irqs - VGIC_NR_PRIVATE_IRQS);
b->private = kzalloc(sizeof(unsigned long) * nr_longs, GFP_KERNEL);
if (!b->private)
return -ENOMEM;
b->shared = b->private + nr_cpus;
return 0;
}
static void vgic_free_bitmap(struct vgic_bitmap *b)
{
kfree(b->private);
b->private = NULL;
b->shared = NULL;
}
/*
* Call this function to convert a u64 value to an unsigned long * bitmask
* in a way that works on both 32-bit and 64-bit LE and BE platforms.
*
* Warning: Calling this function may modify *val.
*/
static unsigned long *u64_to_bitmask(u64 *val)
{
#if defined(CONFIG_CPU_BIG_ENDIAN) && BITS_PER_LONG == 32
*val = (*val >> 32) | (*val << 32);
#endif
return (unsigned long *)val;
}
u32 *vgic_bitmap_get_reg(struct vgic_bitmap *x, int cpuid, u32 offset)
{
offset >>= 2;
if (!offset)
return (u32 *)(x->private + cpuid) + REG_OFFSET_SWIZZLE;
else
return (u32 *)(x->shared) + ((offset - 1) ^ REG_OFFSET_SWIZZLE);
}
static int vgic_bitmap_get_irq_val(struct vgic_bitmap *x,
int cpuid, int irq)
{
if (irq < VGIC_NR_PRIVATE_IRQS)
return test_bit(irq, x->private + cpuid);
return test_bit(irq - VGIC_NR_PRIVATE_IRQS, x->shared);
}
void vgic_bitmap_set_irq_val(struct vgic_bitmap *x, int cpuid,
int irq, int val)
{
unsigned long *reg;
if (irq < VGIC_NR_PRIVATE_IRQS) {
reg = x->private + cpuid;
} else {
reg = x->shared;
irq -= VGIC_NR_PRIVATE_IRQS;
}
if (val)
set_bit(irq, reg);
else
clear_bit(irq, reg);
}
static unsigned long *vgic_bitmap_get_cpu_map(struct vgic_bitmap *x, int cpuid)
{
return x->private + cpuid;
}
unsigned long *vgic_bitmap_get_shared_map(struct vgic_bitmap *x)
{
return x->shared;
}
static int vgic_init_bytemap(struct vgic_bytemap *x, int nr_cpus, int nr_irqs)
{
int size;
size = nr_cpus * VGIC_NR_PRIVATE_IRQS;
size += nr_irqs - VGIC_NR_PRIVATE_IRQS;
x->private = kzalloc(size, GFP_KERNEL);
if (!x->private)
return -ENOMEM;
x->shared = x->private + nr_cpus * VGIC_NR_PRIVATE_IRQS / sizeof(u32);
return 0;
}
static void vgic_free_bytemap(struct vgic_bytemap *b)
{
kfree(b->private);
b->private = NULL;
b->shared = NULL;
}
u32 *vgic_bytemap_get_reg(struct vgic_bytemap *x, int cpuid, u32 offset)
{
u32 *reg;
if (offset < VGIC_NR_PRIVATE_IRQS) {
reg = x->private;
offset += cpuid * VGIC_NR_PRIVATE_IRQS;
} else {
reg = x->shared;
offset -= VGIC_NR_PRIVATE_IRQS;
}
return reg + (offset / sizeof(u32));
}
#define VGIC_CFG_LEVEL 0
#define VGIC_CFG_EDGE 1
static bool vgic_irq_is_edge(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
int irq_val;
irq_val = vgic_bitmap_get_irq_val(&dist->irq_cfg, vcpu->vcpu_id, irq);
return irq_val == VGIC_CFG_EDGE;
}
static int vgic_irq_is_enabled(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_enabled, vcpu->vcpu_id, irq);
}
static int vgic_irq_is_queued(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_queued, vcpu->vcpu_id, irq);
}
static int vgic_irq_is_active(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_active, vcpu->vcpu_id, irq);
}
static void vgic_irq_set_queued(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_queued, vcpu->vcpu_id, irq, 1);
}
static void vgic_irq_clear_queued(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_queued, vcpu->vcpu_id, irq, 0);
}
static void vgic_irq_set_active(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_active, vcpu->vcpu_id, irq, 1);
}
static void vgic_irq_clear_active(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_active, vcpu->vcpu_id, irq, 0);
}
static int vgic_dist_irq_get_level(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_level, vcpu->vcpu_id, irq);
}
static void vgic_dist_irq_set_level(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_level, vcpu->vcpu_id, irq, 1);
}
static void vgic_dist_irq_clear_level(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_level, vcpu->vcpu_id, irq, 0);
}
static int vgic_dist_irq_soft_pend(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_soft_pend, vcpu->vcpu_id, irq);
}
static void vgic_dist_irq_clear_soft_pend(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_soft_pend, vcpu->vcpu_id, irq, 0);
}
static int vgic_dist_irq_is_pending(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_pending, vcpu->vcpu_id, irq);
}
void vgic_dist_irq_set_pending(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_pending, vcpu->vcpu_id, irq, 1);
}
void vgic_dist_irq_clear_pending(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_pending, vcpu->vcpu_id, irq, 0);
}
static void vgic_cpu_irq_set(struct kvm_vcpu *vcpu, int irq)
{
if (irq < VGIC_NR_PRIVATE_IRQS)
set_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
else
set_bit(irq - VGIC_NR_PRIVATE_IRQS,
vcpu->arch.vgic_cpu.pending_shared);
}
void vgic_cpu_irq_clear(struct kvm_vcpu *vcpu, int irq)
{
if (irq < VGIC_NR_PRIVATE_IRQS)
clear_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
else
clear_bit(irq - VGIC_NR_PRIVATE_IRQS,
vcpu->arch.vgic_cpu.pending_shared);
}
static bool vgic_can_sample_irq(struct kvm_vcpu *vcpu, int irq)
{
return vgic_irq_is_edge(vcpu, irq) || !vgic_irq_is_queued(vcpu, irq);
}
/**
* vgic_reg_access - access vgic register
* @mmio: pointer to the data describing the mmio access
* @reg: pointer to the virtual backing of vgic distributor data
* @offset: least significant 2 bits used for word offset
* @mode: ACCESS_ mode (see defines above)
*
* Helper to make vgic register access easier using one of the access
* modes defined for vgic register access
* (read,raz,write-ignored,setbit,clearbit,write)
*/
void vgic_reg_access(struct kvm_exit_mmio *mmio, u32 *reg,
phys_addr_t offset, int mode)
{
int word_offset = (offset & 3) * 8;
u32 mask = (1UL << (mmio->len * 8)) - 1;
u32 regval;
/*
* Any alignment fault should have been delivered to the guest
* directly (ARM ARM B3.12.7 "Prioritization of aborts").
*/
if (reg) {
regval = *reg;
} else {
BUG_ON(mode != (ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED));
regval = 0;
}
if (mmio->is_write) {
u32 data = mmio_data_read(mmio, mask) << word_offset;
switch (ACCESS_WRITE_MASK(mode)) {
case ACCESS_WRITE_IGNORED:
return;
case ACCESS_WRITE_SETBIT:
regval |= data;
break;
case ACCESS_WRITE_CLEARBIT:
regval &= ~data;
break;
case ACCESS_WRITE_VALUE:
regval = (regval & ~(mask << word_offset)) | data;
break;
}
*reg = regval;
} else {
switch (ACCESS_READ_MASK(mode)) {
case ACCESS_READ_RAZ:
regval = 0;
/* fall through */
case ACCESS_READ_VALUE:
mmio_data_write(mmio, mask, regval >> word_offset);
}
}
}
bool handle_mmio_raz_wi(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
vgic_reg_access(mmio, NULL, offset,
ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED);
return false;
}
bool vgic_handle_enable_reg(struct kvm *kvm, struct kvm_exit_mmio *mmio,
phys_addr_t offset, int vcpu_id, int access)
{
u32 *reg;
int mode = ACCESS_READ_VALUE | access;
struct kvm_vcpu *target_vcpu = kvm_get_vcpu(kvm, vcpu_id);
reg = vgic_bitmap_get_reg(&kvm->arch.vgic.irq_enabled, vcpu_id, offset);
vgic_reg_access(mmio, reg, offset, mode);
if (mmio->is_write) {
if (access & ACCESS_WRITE_CLEARBIT) {
if (offset < 4) /* Force SGI enabled */
*reg |= 0xffff;
vgic_retire_disabled_irqs(target_vcpu);
}
vgic_update_state(kvm);
return true;
}
return false;
}
bool vgic_handle_set_pending_reg(struct kvm *kvm,
struct kvm_exit_mmio *mmio,
phys_addr_t offset, int vcpu_id)
{
u32 *reg, orig;
u32 level_mask;
int mode = ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT;
struct vgic_dist *dist = &kvm->arch.vgic;
reg = vgic_bitmap_get_reg(&dist->irq_cfg, vcpu_id, offset);
level_mask = (~(*reg));
/* Mark both level and edge triggered irqs as pending */
reg = vgic_bitmap_get_reg(&dist->irq_pending, vcpu_id, offset);
orig = *reg;
vgic_reg_access(mmio, reg, offset, mode);
if (mmio->is_write) {
/* Set the soft-pending flag only for level-triggered irqs */
reg = vgic_bitmap_get_reg(&dist->irq_soft_pend,
vcpu_id, offset);
vgic_reg_access(mmio, reg, offset, mode);
*reg &= level_mask;
/* Ignore writes to SGIs */
if (offset < 2) {
*reg &= ~0xffff;
*reg |= orig & 0xffff;
}
vgic_update_state(kvm);
return true;
}
return false;
}
bool vgic_handle_clear_pending_reg(struct kvm *kvm,
struct kvm_exit_mmio *mmio,
phys_addr_t offset, int vcpu_id)
{
u32 *level_active;
u32 *reg, orig;
int mode = ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT;
struct vgic_dist *dist = &kvm->arch.vgic;
reg = vgic_bitmap_get_reg(&dist->irq_pending, vcpu_id, offset);
orig = *reg;
vgic_reg_access(mmio, reg, offset, mode);
if (mmio->is_write) {
/* Re-set level triggered level-active interrupts */
level_active = vgic_bitmap_get_reg(&dist->irq_level,
vcpu_id, offset);
reg = vgic_bitmap_get_reg(&dist->irq_pending, vcpu_id, offset);
*reg |= *level_active;
/* Ignore writes to SGIs */
if (offset < 2) {
*reg &= ~0xffff;
*reg |= orig & 0xffff;
}
/* Clear soft-pending flags */
reg = vgic_bitmap_get_reg(&dist->irq_soft_pend,
vcpu_id, offset);
vgic_reg_access(mmio, reg, offset, mode);
vgic_update_state(kvm);
return true;
}
return false;
}
bool vgic_handle_set_active_reg(struct kvm *kvm,
struct kvm_exit_mmio *mmio,
phys_addr_t offset, int vcpu_id)
{
u32 *reg;
struct vgic_dist *dist = &kvm->arch.vgic;
reg = vgic_bitmap_get_reg(&dist->irq_active, vcpu_id, offset);
vgic_reg_access(mmio, reg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
if (mmio->is_write) {
vgic_update_state(kvm);
return true;
}
return false;
}
bool vgic_handle_clear_active_reg(struct kvm *kvm,
struct kvm_exit_mmio *mmio,
phys_addr_t offset, int vcpu_id)
{
u32 *reg;
struct vgic_dist *dist = &kvm->arch.vgic;
reg = vgic_bitmap_get_reg(&dist->irq_active, vcpu_id, offset);
vgic_reg_access(mmio, reg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
if (mmio->is_write) {
vgic_update_state(kvm);
return true;
}
return false;
}
static u32 vgic_cfg_expand(u16 val)
{
u32 res = 0;
int i;
/*
* Turn a 16bit value like abcd...mnop into a 32bit word
* a0b0c0d0...m0n0o0p0, which is what the HW cfg register is.
*/
for (i = 0; i < 16; i++)
res |= ((val >> i) & VGIC_CFG_EDGE) << (2 * i + 1);
return res;
}
static u16 vgic_cfg_compress(u32 val)
{
u16 res = 0;
int i;
/*
* Turn a 32bit word a0b0c0d0...m0n0o0p0 into 16bit value like
* abcd...mnop which is what we really care about.
*/
for (i = 0; i < 16; i++)
res |= ((val >> (i * 2 + 1)) & VGIC_CFG_EDGE) << i;
return res;
}
/*
* The distributor uses 2 bits per IRQ for the CFG register, but the
* LSB is always 0. As such, we only keep the upper bit, and use the
* two above functions to compress/expand the bits
*/
bool vgic_handle_cfg_reg(u32 *reg, struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
u32 val;
if (offset & 4)
val = *reg >> 16;
else
val = *reg & 0xffff;
val = vgic_cfg_expand(val);
vgic_reg_access(mmio, &val, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
if (mmio->is_write) {
if (offset < 8) {
*reg = ~0U; /* Force PPIs/SGIs to 1 */
return false;
}
val = vgic_cfg_compress(val);
if (offset & 4) {
*reg &= 0xffff;
*reg |= val << 16;
} else {
*reg &= 0xffff << 16;
*reg |= val;
}
}
return false;
}
/**
* vgic_unqueue_irqs - move pending/active IRQs from LRs to the distributor
* @vgic_cpu: Pointer to the vgic_cpu struct holding the LRs
*
* Move any IRQs that have already been assigned to LRs back to the
* emulated distributor state so that the complete emulated state can be read
* from the main emulation structures without investigating the LRs.
*/
void vgic_unqueue_irqs(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
int i;
for_each_set_bit(i, vgic_cpu->lr_used, vgic_cpu->nr_lr) {
struct vgic_lr lr = vgic_get_lr(vcpu, i);
/*
* There are three options for the state bits:
*
* 01: pending
* 10: active
* 11: pending and active
*/
BUG_ON(!(lr.state & LR_STATE_MASK));
/* Reestablish SGI source for pending and active IRQs */
if (lr.irq < VGIC_NR_SGIS)
add_sgi_source(vcpu, lr.irq, lr.source);
/*
* If the LR holds an active (10) or a pending and active (11)
* interrupt then move the active state to the
* distributor tracking bit.
*/
if (lr.state & LR_STATE_ACTIVE) {
vgic_irq_set_active(vcpu, lr.irq);
lr.state &= ~LR_STATE_ACTIVE;
}
/*
* Reestablish the pending state on the distributor and the
* CPU interface. It may have already been pending, but that
* is fine, then we are only setting a few bits that were
* already set.
*/
if (lr.state & LR_STATE_PENDING) {
vgic_dist_irq_set_pending(vcpu, lr.irq);
lr.state &= ~LR_STATE_PENDING;
}
vgic_set_lr(vcpu, i, lr);
/*
* Mark the LR as free for other use.
*/
BUG_ON(lr.state & LR_STATE_MASK);
vgic_retire_lr(i, lr.irq, vcpu);
vgic_irq_clear_queued(vcpu, lr.irq);
/* Finally update the VGIC state. */
vgic_update_state(vcpu->kvm);
}
}
const
struct vgic_io_range *vgic_find_range(const struct vgic_io_range *ranges,
int len, gpa_t offset)
{
while (ranges->len) {
if (offset >= ranges->base &&
(offset + len) <= (ranges->base + ranges->len))
return ranges;
ranges++;
}
return NULL;
}
static bool vgic_validate_access(const struct vgic_dist *dist,
const struct vgic_io_range *range,
unsigned long offset)
{
int irq;
if (!range->bits_per_irq)
return true; /* Not an irq-based access */
irq = offset * 8 / range->bits_per_irq;
if (irq >= dist->nr_irqs)
return false;
return true;
}
/*
* Call the respective handler function for the given range.
* We split up any 64 bit accesses into two consecutive 32 bit
* handler calls and merge the result afterwards.
* We do this in a little endian fashion regardless of the host's
* or guest's endianness, because the GIC is always LE and the rest of
* the code (vgic_reg_access) also puts it in a LE fashion already.
* At this point we have already identified the handle function, so
* range points to that one entry and offset is relative to this.
*/
static bool call_range_handler(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio,
unsigned long offset,
const struct vgic_io_range *range)
{
struct kvm_exit_mmio mmio32;
bool ret;
if (likely(mmio->len <= 4))
return range->handle_mmio(vcpu, mmio, offset);
/*
* Any access bigger than 4 bytes (that we currently handle in KVM)
* is actually 8 bytes long, caused by a 64-bit access
*/
mmio32.len = 4;
mmio32.is_write = mmio->is_write;
mmio32.private = mmio->private;
mmio32.phys_addr = mmio->phys_addr + 4;
mmio32.data = &((u32 *)mmio->data)[1];
ret = range->handle_mmio(vcpu, &mmio32, offset + 4);
mmio32.phys_addr = mmio->phys_addr;
mmio32.data = &((u32 *)mmio->data)[0];
ret |= range->handle_mmio(vcpu, &mmio32, offset);
return ret;
}
/**
* vgic_handle_mmio_access - handle an in-kernel MMIO access
* This is called by the read/write KVM IO device wrappers below.
* @vcpu: pointer to the vcpu performing the access
* @this: pointer to the KVM IO device in charge
* @addr: guest physical address of the access
* @len: size of the access
* @val: pointer to the data region
* @is_write: read or write access
*
* returns true if the MMIO access could be performed
*/
static int vgic_handle_mmio_access(struct kvm_vcpu *vcpu,
struct kvm_io_device *this, gpa_t addr,
int len, void *val, bool is_write)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
struct vgic_io_device *iodev = container_of(this,
struct vgic_io_device, dev);
struct kvm_run *run = vcpu->run;
const struct vgic_io_range *range;
struct kvm_exit_mmio mmio;
bool updated_state;
gpa_t offset;
offset = addr - iodev->addr;
range = vgic_find_range(iodev->reg_ranges, len, offset);
if (unlikely(!range || !range->handle_mmio)) {
pr_warn("Unhandled access %d %08llx %d\n", is_write, addr, len);
return -ENXIO;
}
mmio.phys_addr = addr;
mmio.len = len;
mmio.is_write = is_write;
mmio.data = val;
mmio.private = iodev->redist_vcpu;
spin_lock(&dist->lock);
offset -= range->base;
if (vgic_validate_access(dist, range, offset)) {
updated_state = call_range_handler(vcpu, &mmio, offset, range);
} else {
if (!is_write)
memset(val, 0, len);
updated_state = false;
}
spin_unlock(&dist->lock);
run->mmio.is_write = is_write;
run->mmio.len = len;
run->mmio.phys_addr = addr;
memcpy(run->mmio.data, val, len);
kvm_handle_mmio_return(vcpu, run);
if (updated_state)
vgic_kick_vcpus(vcpu->kvm);
return 0;
}
static int vgic_handle_mmio_read(struct kvm_vcpu *vcpu,
struct kvm_io_device *this,
gpa_t addr, int len, void *val)
{
return vgic_handle_mmio_access(vcpu, this, addr, len, val, false);
}
static int vgic_handle_mmio_write(struct kvm_vcpu *vcpu,
struct kvm_io_device *this,
gpa_t addr, int len, const void *val)
{
return vgic_handle_mmio_access(vcpu, this, addr, len, (void *)val,
true);
}
struct kvm_io_device_ops vgic_io_ops = {
.read = vgic_handle_mmio_read,
.write = vgic_handle_mmio_write,
};
/**
* vgic_register_kvm_io_dev - register VGIC register frame on the KVM I/O bus
* @kvm: The VM structure pointer
* @base: The (guest) base address for the register frame
* @len: Length of the register frame window
* @ranges: Describing the handler functions for each register
* @redist_vcpu_id: The VCPU ID to pass on to the handlers on call
* @iodev: Points to memory to be passed on to the handler
*
* @iodev stores the parameters of this function to be usable by the handler
* respectively the dispatcher function (since the KVM I/O bus framework lacks
* an opaque parameter). Initialization is done in this function, but the
* reference should be valid and unique for the whole VGIC lifetime.
* If the register frame is not mapped for a specific VCPU, pass -1 to
* @redist_vcpu_id.
*/
int vgic_register_kvm_io_dev(struct kvm *kvm, gpa_t base, int len,
const struct vgic_io_range *ranges,
int redist_vcpu_id,
struct vgic_io_device *iodev)
{
struct kvm_vcpu *vcpu = NULL;
int ret;
if (redist_vcpu_id >= 0)
vcpu = kvm_get_vcpu(kvm, redist_vcpu_id);
iodev->addr = base;
iodev->len = len;
iodev->reg_ranges = ranges;
iodev->redist_vcpu = vcpu;
kvm_iodevice_init(&iodev->dev, &vgic_io_ops);
mutex_lock(&kvm->slots_lock);
ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, base, len,
&iodev->dev);
mutex_unlock(&kvm->slots_lock);
/* Mark the iodev as invalid if registration fails. */
if (ret)
iodev->dev.ops = NULL;
return ret;
}
static int vgic_nr_shared_irqs(struct vgic_dist *dist)
{
return dist->nr_irqs - VGIC_NR_PRIVATE_IRQS;
}
static int compute_active_for_cpu(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
unsigned long *active, *enabled, *act_percpu, *act_shared;
unsigned long active_private, active_shared;
int nr_shared = vgic_nr_shared_irqs(dist);
int vcpu_id;
vcpu_id = vcpu->vcpu_id;
act_percpu = vcpu->arch.vgic_cpu.active_percpu;
act_shared = vcpu->arch.vgic_cpu.active_shared;
active = vgic_bitmap_get_cpu_map(&dist->irq_active, vcpu_id);
enabled = vgic_bitmap_get_cpu_map(&dist->irq_enabled, vcpu_id);
bitmap_and(act_percpu, active, enabled, VGIC_NR_PRIVATE_IRQS);
active = vgic_bitmap_get_shared_map(&dist->irq_active);
enabled = vgic_bitmap_get_shared_map(&dist->irq_enabled);
bitmap_and(act_shared, active, enabled, nr_shared);
bitmap_and(act_shared, act_shared,
vgic_bitmap_get_shared_map(&dist->irq_spi_target[vcpu_id]),
nr_shared);
active_private = find_first_bit(act_percpu, VGIC_NR_PRIVATE_IRQS);
active_shared = find_first_bit(act_shared, nr_shared);
return (active_private < VGIC_NR_PRIVATE_IRQS ||
active_shared < nr_shared);
}
static int compute_pending_for_cpu(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
unsigned long *pending, *enabled, *pend_percpu, *pend_shared;
unsigned long pending_private, pending_shared;
int nr_shared = vgic_nr_shared_irqs(dist);
int vcpu_id;
vcpu_id = vcpu->vcpu_id;
pend_percpu = vcpu->arch.vgic_cpu.pending_percpu;
pend_shared = vcpu->arch.vgic_cpu.pending_shared;
pending = vgic_bitmap_get_cpu_map(&dist->irq_pending, vcpu_id);
enabled = vgic_bitmap_get_cpu_map(&dist->irq_enabled, vcpu_id);
bitmap_and(pend_percpu, pending, enabled, VGIC_NR_PRIVATE_IRQS);
pending = vgic_bitmap_get_shared_map(&dist->irq_pending);
enabled = vgic_bitmap_get_shared_map(&dist->irq_enabled);
bitmap_and(pend_shared, pending, enabled, nr_shared);
bitmap_and(pend_shared, pend_shared,
vgic_bitmap_get_shared_map(&dist->irq_spi_target[vcpu_id]),
nr_shared);
pending_private = find_first_bit(pend_percpu, VGIC_NR_PRIVATE_IRQS);
pending_shared = find_first_bit(pend_shared, nr_shared);
return (pending_private < VGIC_NR_PRIVATE_IRQS ||
pending_shared < vgic_nr_shared_irqs(dist));
}
/*
* Update the interrupt state and determine which CPUs have pending
* or active interrupts. Must be called with distributor lock held.
*/
void vgic_update_state(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int c;
if (!dist->enabled) {
set_bit(0, dist->irq_pending_on_cpu);
return;
}
kvm_for_each_vcpu(c, vcpu, kvm) {
if (compute_pending_for_cpu(vcpu))
set_bit(c, dist->irq_pending_on_cpu);
if (compute_active_for_cpu(vcpu))
set_bit(c, dist->irq_active_on_cpu);
else
clear_bit(c, dist->irq_active_on_cpu);
}
}
static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr)
{
return vgic_ops->get_lr(vcpu, lr);
}
static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr,
struct vgic_lr vlr)
{
vgic_ops->set_lr(vcpu, lr, vlr);
}
static void vgic_sync_lr_elrsr(struct kvm_vcpu *vcpu, int lr,
struct vgic_lr vlr)
{
vgic_ops->sync_lr_elrsr(vcpu, lr, vlr);
}
static inline u64 vgic_get_elrsr(struct kvm_vcpu *vcpu)
{
return vgic_ops->get_elrsr(vcpu);
}
static inline u64 vgic_get_eisr(struct kvm_vcpu *vcpu)
{
return vgic_ops->get_eisr(vcpu);
}
static inline void vgic_clear_eisr(struct kvm_vcpu *vcpu)
{
vgic_ops->clear_eisr(vcpu);
}
static inline u32 vgic_get_interrupt_status(struct kvm_vcpu *vcpu)
{
return vgic_ops->get_interrupt_status(vcpu);
}
static inline void vgic_enable_underflow(struct kvm_vcpu *vcpu)
{
vgic_ops->enable_underflow(vcpu);
}
static inline void vgic_disable_underflow(struct kvm_vcpu *vcpu)
{
vgic_ops->disable_underflow(vcpu);
}
void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
{
vgic_ops->get_vmcr(vcpu, vmcr);
}
void vgic_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
{
vgic_ops->set_vmcr(vcpu, vmcr);
}
static inline void vgic_enable(struct kvm_vcpu *vcpu)
{
vgic_ops->enable(vcpu);
}
static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_lr vlr = vgic_get_lr(vcpu, lr_nr);
vlr.state = 0;
vgic_set_lr(vcpu, lr_nr, vlr);
clear_bit(lr_nr, vgic_cpu->lr_used);
vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
vgic_sync_lr_elrsr(vcpu, lr_nr, vlr);
}
/*
* An interrupt may have been disabled after being made pending on the
* CPU interface (the classic case is a timer running while we're
* rebooting the guest - the interrupt would kick as soon as the CPU
* interface gets enabled, with deadly consequences).
*
* The solution is to examine already active LRs, and check the
* interrupt is still enabled. If not, just retire it.
*/
static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
int lr;
for_each_set_bit(lr, vgic_cpu->lr_used, vgic->nr_lr) {
struct vgic_lr vlr = vgic_get_lr(vcpu, lr);
if (!vgic_irq_is_enabled(vcpu, vlr.irq)) {
vgic_retire_lr(lr, vlr.irq, vcpu);
if (vgic_irq_is_queued(vcpu, vlr.irq))
vgic_irq_clear_queued(vcpu, vlr.irq);
}
}
}
static void vgic_queue_irq_to_lr(struct kvm_vcpu *vcpu, int irq,
int lr_nr, struct vgic_lr vlr)
{
if (vgic_irq_is_active(vcpu, irq)) {
vlr.state |= LR_STATE_ACTIVE;
kvm_debug("Set active, clear distributor: 0x%x\n", vlr.state);
vgic_irq_clear_active(vcpu, irq);
vgic_update_state(vcpu->kvm);
} else if (vgic_dist_irq_is_pending(vcpu, irq)) {
vlr.state |= LR_STATE_PENDING;
kvm_debug("Set pending: 0x%x\n", vlr.state);
}
if (!vgic_irq_is_edge(vcpu, irq))
vlr.state |= LR_EOI_INT;
vgic_set_lr(vcpu, lr_nr, vlr);
vgic_sync_lr_elrsr(vcpu, lr_nr, vlr);
}
/*
* Queue an interrupt to a CPU virtual interface. Return true on success,
* or false if it wasn't possible to queue it.
* sgi_source must be zero for any non-SGI interrupts.
*/
bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
struct vgic_lr vlr;
int lr;
/* Sanitize the input... */
BUG_ON(sgi_source_id & ~7);
BUG_ON(sgi_source_id && irq >= VGIC_NR_SGIS);
BUG_ON(irq >= dist->nr_irqs);
kvm_debug("Queue IRQ%d\n", irq);
lr = vgic_cpu->vgic_irq_lr_map[irq];
/* Do we have an active interrupt for the same CPUID? */
if (lr != LR_EMPTY) {
vlr = vgic_get_lr(vcpu, lr);
if (vlr.source == sgi_source_id) {
kvm_debug("LR%d piggyback for IRQ%d\n", lr, vlr.irq);
BUG_ON(!test_bit(lr, vgic_cpu->lr_used));
vgic_queue_irq_to_lr(vcpu, irq, lr, vlr);
return true;
}
}
/* Try to use another LR for this interrupt */
lr = find_first_zero_bit((unsigned long *)vgic_cpu->lr_used,
vgic->nr_lr);
if (lr >= vgic->nr_lr)
return false;
kvm_debug("LR%d allocated for IRQ%d %x\n", lr, irq, sgi_source_id);
vgic_cpu->vgic_irq_lr_map[irq] = lr;
set_bit(lr, vgic_cpu->lr_used);
vlr.irq = irq;
vlr.source = sgi_source_id;
vlr.state = 0;
vgic_queue_irq_to_lr(vcpu, irq, lr, vlr);
return true;
}
static bool vgic_queue_hwirq(struct kvm_vcpu *vcpu, int irq)
{
if (!vgic_can_sample_irq(vcpu, irq))
return true; /* level interrupt, already queued */
if (vgic_queue_irq(vcpu, 0, irq)) {
if (vgic_irq_is_edge(vcpu, irq)) {
vgic_dist_irq_clear_pending(vcpu, irq);
vgic_cpu_irq_clear(vcpu, irq);
} else {
vgic_irq_set_queued(vcpu, irq);
}
return true;
}
return false;
}
/*
* Fill the list registers with pending interrupts before running the
* guest.
*/
static void __kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
unsigned long *pa_percpu, *pa_shared;
int i, vcpu_id;
int overflow = 0;
int nr_shared = vgic_nr_shared_irqs(dist);
vcpu_id = vcpu->vcpu_id;
pa_percpu = vcpu->arch.vgic_cpu.pend_act_percpu;
pa_shared = vcpu->arch.vgic_cpu.pend_act_shared;
bitmap_or(pa_percpu, vgic_cpu->pending_percpu, vgic_cpu->active_percpu,
VGIC_NR_PRIVATE_IRQS);
bitmap_or(pa_shared, vgic_cpu->pending_shared, vgic_cpu->active_shared,
nr_shared);
/*
* We may not have any pending interrupt, or the interrupts
* may have been serviced from another vcpu. In all cases,
* move along.
*/
if (!kvm_vgic_vcpu_pending_irq(vcpu) && !kvm_vgic_vcpu_active_irq(vcpu))
goto epilog;
/* SGIs */
for_each_set_bit(i, pa_percpu, VGIC_NR_SGIS) {
if (!queue_sgi(vcpu, i))
overflow = 1;
}
/* PPIs */
for_each_set_bit_from(i, pa_percpu, VGIC_NR_PRIVATE_IRQS) {
if (!vgic_queue_hwirq(vcpu, i))
overflow = 1;
}
/* SPIs */
for_each_set_bit(i, pa_shared, nr_shared) {
if (!vgic_queue_hwirq(vcpu, i + VGIC_NR_PRIVATE_IRQS))
overflow = 1;
}
epilog:
if (overflow) {
vgic_enable_underflow(vcpu);
} else {
vgic_disable_underflow(vcpu);
/*
* We're about to run this VCPU, and we've consumed
* everything the distributor had in store for
* us. Claim we don't have anything pending. We'll
* adjust that if needed while exiting.
*/
clear_bit(vcpu_id, dist->irq_pending_on_cpu);
}
}
static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
{
u32 status = vgic_get_interrupt_status(vcpu);
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
bool level_pending = false;
struct kvm *kvm = vcpu->kvm;
kvm_debug("STATUS = %08x\n", status);
if (status & INT_STATUS_EOI) {
/*
* Some level interrupts have been EOIed. Clear their
* active bit.
*/
u64 eisr = vgic_get_eisr(vcpu);
unsigned long *eisr_ptr = u64_to_bitmask(&eisr);
int lr;
for_each_set_bit(lr, eisr_ptr, vgic->nr_lr) {
struct vgic_lr vlr = vgic_get_lr(vcpu, lr);
WARN_ON(vgic_irq_is_edge(vcpu, vlr.irq));
spin_lock(&dist->lock);
vgic_irq_clear_queued(vcpu, vlr.irq);
WARN_ON(vlr.state & LR_STATE_MASK);
vlr.state = 0;
vgic_set_lr(vcpu, lr, vlr);
/*
* If the IRQ was EOIed it was also ACKed and we we
* therefore assume we can clear the soft pending
* state (should it had been set) for this interrupt.
*
* Note: if the IRQ soft pending state was set after
* the IRQ was acked, it actually shouldn't be
* cleared, but we have no way of knowing that unless
* we start trapping ACKs when the soft-pending state
* is set.
*/
vgic_dist_irq_clear_soft_pend(vcpu, vlr.irq);
/*
* kvm_notify_acked_irq calls kvm_set_irq()
* to reset the IRQ level. Need to release the
* lock for kvm_set_irq to grab it.
*/
spin_unlock(&dist->lock);
kvm_notify_acked_irq(kvm, 0,
vlr.irq - VGIC_NR_PRIVATE_IRQS);
spin_lock(&dist->lock);
/* Any additional pending interrupt? */
if (vgic_dist_irq_get_level(vcpu, vlr.irq)) {
vgic_cpu_irq_set(vcpu, vlr.irq);
level_pending = true;
} else {
vgic_dist_irq_clear_pending(vcpu, vlr.irq);
vgic_cpu_irq_clear(vcpu, vlr.irq);
}
spin_unlock(&dist->lock);
/*
* Despite being EOIed, the LR may not have
* been marked as empty.
*/
vgic_sync_lr_elrsr(vcpu, lr, vlr);
}
}
if (status & INT_STATUS_UNDERFLOW)
vgic_disable_underflow(vcpu);
/*
* In the next iterations of the vcpu loop, if we sync the vgic state
* after flushing it, but before entering the guest (this happens for
* pending signals and vmid rollovers), then make sure we don't pick
* up any old maintenance interrupts here.
*/
vgic_clear_eisr(vcpu);
return level_pending;
}
/* Sync back the VGIC state after a guest run */
static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
u64 elrsr;
unsigned long *elrsr_ptr;
int lr, pending;
bool level_pending;
level_pending = vgic_process_maintenance(vcpu);
elrsr = vgic_get_elrsr(vcpu);
elrsr_ptr = u64_to_bitmask(&elrsr);
/* Clear mappings for empty LRs */
for_each_set_bit(lr, elrsr_ptr, vgic->nr_lr) {
struct vgic_lr vlr;
if (!test_and_clear_bit(lr, vgic_cpu->lr_used))
continue;
vlr = vgic_get_lr(vcpu, lr);
BUG_ON(vlr.irq >= dist->nr_irqs);
vgic_cpu->vgic_irq_lr_map[vlr.irq] = LR_EMPTY;
}
/* Check if we still have something up our sleeve... */
pending = find_first_zero_bit(elrsr_ptr, vgic->nr_lr);
if (level_pending || pending < vgic->nr_lr)
set_bit(vcpu->vcpu_id, dist->irq_pending_on_cpu);
}
void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
if (!irqchip_in_kernel(vcpu->kvm))
return;
spin_lock(&dist->lock);
__kvm_vgic_flush_hwstate(vcpu);
spin_unlock(&dist->lock);
}
void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
{
if (!irqchip_in_kernel(vcpu->kvm))
return;
__kvm_vgic_sync_hwstate(vcpu);
}
int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
if (!irqchip_in_kernel(vcpu->kvm))
return 0;
return test_bit(vcpu->vcpu_id, dist->irq_pending_on_cpu);
}
int kvm_vgic_vcpu_active_irq(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
if (!irqchip_in_kernel(vcpu->kvm))
return 0;
return test_bit(vcpu->vcpu_id, dist->irq_active_on_cpu);
}
void vgic_kick_vcpus(struct kvm *kvm)
{
struct kvm_vcpu *vcpu;
int c;
/*
* We've injected an interrupt, time to find out who deserves
* a good kick...
*/
kvm_for_each_vcpu(c, vcpu, kvm) {
if (kvm_vgic_vcpu_pending_irq(vcpu))
kvm_vcpu_kick(vcpu);
}
}
static int vgic_validate_injection(struct kvm_vcpu *vcpu, int irq, int level)
{
int edge_triggered = vgic_irq_is_edge(vcpu, irq);
/*
* Only inject an interrupt if:
* - edge triggered and we have a rising edge
* - level triggered and we change level
*/
if (edge_triggered) {
int state = vgic_dist_irq_is_pending(vcpu, irq);
return level > state;
} else {
int state = vgic_dist_irq_get_level(vcpu, irq);
return level != state;
}
}
static int vgic_update_irq_pending(struct kvm *kvm, int cpuid,
unsigned int irq_num, bool level)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int edge_triggered, level_triggered;
int enabled;
bool ret = true, can_inject = true;
spin_lock(&dist->lock);
vcpu = kvm_get_vcpu(kvm, cpuid);
edge_triggered = vgic_irq_is_edge(vcpu, irq_num);
level_triggered = !edge_triggered;
if (!vgic_validate_injection(vcpu, irq_num, level)) {
ret = false;
goto out;
}
if (irq_num >= VGIC_NR_PRIVATE_IRQS) {
cpuid = dist->irq_spi_cpu[irq_num - VGIC_NR_PRIVATE_IRQS];
if (cpuid == VCPU_NOT_ALLOCATED) {
/* Pretend we use CPU0, and prevent injection */
cpuid = 0;
can_inject = false;
}
vcpu = kvm_get_vcpu(kvm, cpuid);
}
kvm_debug("Inject IRQ%d level %d CPU%d\n", irq_num, level, cpuid);
if (level) {
if (level_triggered)
vgic_dist_irq_set_level(vcpu, irq_num);
vgic_dist_irq_set_pending(vcpu, irq_num);
} else {
if (level_triggered) {
vgic_dist_irq_clear_level(vcpu, irq_num);
if (!vgic_dist_irq_soft_pend(vcpu, irq_num))
vgic_dist_irq_clear_pending(vcpu, irq_num);
}
ret = false;
goto out;
}
enabled = vgic_irq_is_enabled(vcpu, irq_num);
if (!enabled || !can_inject) {
ret = false;
goto out;
}
if (!vgic_can_sample_irq(vcpu, irq_num)) {
/*
* Level interrupt in progress, will be picked up
* when EOId.
*/
ret = false;
goto out;
}
if (level) {
vgic_cpu_irq_set(vcpu, irq_num);
set_bit(cpuid, dist->irq_pending_on_cpu);
}
out:
spin_unlock(&dist->lock);
return ret ? cpuid : -EINVAL;
}
/**
* kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic
* @kvm: The VM structure pointer
* @cpuid: The CPU for PPIs
* @irq_num: The IRQ number that is assigned to the device
* @level: Edge-triggered: true: to trigger the interrupt
* false: to ignore the call
* Level-sensitive true: activates an interrupt
* false: deactivates an interrupt
*
* The GIC is not concerned with devices being active-LOW or active-HIGH for
* level-sensitive interrupts. You can think of the level parameter as 1
* being HIGH and 0 being LOW and all devices being active-HIGH.
*/
int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
bool level)
{
int ret = 0;
int vcpu_id;
if (unlikely(!vgic_initialized(kvm))) {
/*
* We only provide the automatic initialization of the VGIC
* for the legacy case of a GICv2. Any other type must
* be explicitly initialized once setup with the respective
* KVM device call.
*/
if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2) {
ret = -EBUSY;
goto out;
}
mutex_lock(&kvm->lock);
ret = vgic_init(kvm);
mutex_unlock(&kvm->lock);
if (ret)
goto out;
}
if (irq_num >= kvm->arch.vgic.nr_irqs)
return -EINVAL;
vcpu_id = vgic_update_irq_pending(kvm, cpuid, irq_num, level);
if (vcpu_id >= 0) {
/* kick the specified vcpu */
kvm_vcpu_kick(kvm_get_vcpu(kvm, vcpu_id));
}
out:
return ret;
}
static irqreturn_t vgic_maintenance_handler(int irq, void *data)
{
/*
* We cannot rely on the vgic maintenance interrupt to be
* delivered synchronously. This means we can only use it to
* exit the VM, and we perform the handling of EOIed
* interrupts on the exit path (see vgic_process_maintenance).
*/
return IRQ_HANDLED;
}
void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
kfree(vgic_cpu->pending_shared);
kfree(vgic_cpu->active_shared);
kfree(vgic_cpu->pend_act_shared);
kfree(vgic_cpu->vgic_irq_lr_map);
vgic_cpu->pending_shared = NULL;
vgic_cpu->active_shared = NULL;
vgic_cpu->pend_act_shared = NULL;
vgic_cpu->vgic_irq_lr_map = NULL;
}
static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
int sz = (nr_irqs - VGIC_NR_PRIVATE_IRQS) / 8;
vgic_cpu->pending_shared = kzalloc(sz, GFP_KERNEL);
vgic_cpu->active_shared = kzalloc(sz, GFP_KERNEL);
vgic_cpu->pend_act_shared = kzalloc(sz, GFP_KERNEL);
vgic_cpu->vgic_irq_lr_map = kmalloc(nr_irqs, GFP_KERNEL);
if (!vgic_cpu->pending_shared
|| !vgic_cpu->active_shared
|| !vgic_cpu->pend_act_shared
|| !vgic_cpu->vgic_irq_lr_map) {
kvm_vgic_vcpu_destroy(vcpu);
return -ENOMEM;
}
memset(vgic_cpu->vgic_irq_lr_map, LR_EMPTY, nr_irqs);
/*
* Store the number of LRs per vcpu, so we don't have to go
* all the way to the distributor structure to find out. Only
* assembly code should use this one.
*/
vgic_cpu->nr_lr = vgic->nr_lr;
return 0;
}
/**
* kvm_vgic_get_max_vcpus - Get the maximum number of VCPUs allowed by HW
*
* The host's GIC naturally limits the maximum amount of VCPUs a guest
* can use.
*/
int kvm_vgic_get_max_vcpus(void)
{
return vgic->max_gic_vcpus;
}
void kvm_vgic_destroy(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int i;
kvm_for_each_vcpu(i, vcpu, kvm)
kvm_vgic_vcpu_destroy(vcpu);
vgic_free_bitmap(&dist->irq_enabled);
vgic_free_bitmap(&dist->irq_level);
vgic_free_bitmap(&dist->irq_pending);
vgic_free_bitmap(&dist->irq_soft_pend);
vgic_free_bitmap(&dist->irq_queued);
vgic_free_bitmap(&dist->irq_cfg);
vgic_free_bytemap(&dist->irq_priority);
if (dist->irq_spi_target) {
for (i = 0; i < dist->nr_cpus; i++)
vgic_free_bitmap(&dist->irq_spi_target[i]);
}
kfree(dist->irq_sgi_sources);
kfree(dist->irq_spi_cpu);
kfree(dist->irq_spi_mpidr);
kfree(dist->irq_spi_target);
kfree(dist->irq_pending_on_cpu);
kfree(dist->irq_active_on_cpu);
dist->irq_sgi_sources = NULL;
dist->irq_spi_cpu = NULL;
dist->irq_spi_target = NULL;
dist->irq_pending_on_cpu = NULL;
dist->irq_active_on_cpu = NULL;
dist->nr_cpus = 0;
}
/*
* Allocate and initialize the various data structures. Must be called
* with kvm->lock held!
*/
int vgic_init(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int nr_cpus, nr_irqs;
int ret, i, vcpu_id;
if (vgic_initialized(kvm))
return 0;
nr_cpus = dist->nr_cpus = atomic_read(&kvm->online_vcpus);
if (!nr_cpus) /* No vcpus? Can't be good... */
return -ENODEV;
/*
* If nobody configured the number of interrupts, use the
* legacy one.
*/
if (!dist->nr_irqs)
dist->nr_irqs = VGIC_NR_IRQS_LEGACY;
nr_irqs = dist->nr_irqs;
ret = vgic_init_bitmap(&dist->irq_enabled, nr_cpus, nr_irqs);
ret |= vgic_init_bitmap(&dist->irq_level, nr_cpus, nr_irqs);
ret |= vgic_init_bitmap(&dist->irq_pending, nr_cpus, nr_irqs);
ret |= vgic_init_bitmap(&dist->irq_soft_pend, nr_cpus, nr_irqs);
ret |= vgic_init_bitmap(&dist->irq_queued, nr_cpus, nr_irqs);
ret |= vgic_init_bitmap(&dist->irq_active, nr_cpus, nr_irqs);
ret |= vgic_init_bitmap(&dist->irq_cfg, nr_cpus, nr_irqs);
ret |= vgic_init_bytemap(&dist->irq_priority, nr_cpus, nr_irqs);
if (ret)
goto out;
dist->irq_sgi_sources = kzalloc(nr_cpus * VGIC_NR_SGIS, GFP_KERNEL);
dist->irq_spi_cpu = kzalloc(nr_irqs - VGIC_NR_PRIVATE_IRQS, GFP_KERNEL);
dist->irq_spi_target = kzalloc(sizeof(*dist->irq_spi_target) * nr_cpus,
GFP_KERNEL);
dist->irq_pending_on_cpu = kzalloc(BITS_TO_LONGS(nr_cpus) * sizeof(long),
GFP_KERNEL);
dist->irq_active_on_cpu = kzalloc(BITS_TO_LONGS(nr_cpus) * sizeof(long),
GFP_KERNEL);
if (!dist->irq_sgi_sources ||
!dist->irq_spi_cpu ||
!dist->irq_spi_target ||
!dist->irq_pending_on_cpu ||
!dist->irq_active_on_cpu) {
ret = -ENOMEM;
goto out;
}
for (i = 0; i < nr_cpus; i++)
ret |= vgic_init_bitmap(&dist->irq_spi_target[i],
nr_cpus, nr_irqs);
if (ret)
goto out;
ret = kvm->arch.vgic.vm_ops.init_model(kvm);
if (ret)
goto out;
kvm_for_each_vcpu(vcpu_id, vcpu, kvm) {
ret = vgic_vcpu_init_maps(vcpu, nr_irqs);
if (ret) {
kvm_err("VGIC: Failed to allocate vcpu memory\n");
break;
}
for (i = 0; i < dist->nr_irqs; i++) {
if (i < VGIC_NR_PPIS)
vgic_bitmap_set_irq_val(&dist->irq_enabled,
vcpu->vcpu_id, i, 1);
if (i < VGIC_NR_PRIVATE_IRQS)
vgic_bitmap_set_irq_val(&dist->irq_cfg,
vcpu->vcpu_id, i,
VGIC_CFG_EDGE);
}
vgic_enable(vcpu);
}
out:
if (ret)
kvm_vgic_destroy(kvm);
return ret;
}
static int init_vgic_model(struct kvm *kvm, int type)
{
switch (type) {
case KVM_DEV_TYPE_ARM_VGIC_V2:
vgic_v2_init_emulation(kvm);
break;
#ifdef CONFIG_ARM_GIC_V3
case KVM_DEV_TYPE_ARM_VGIC_V3:
vgic_v3_init_emulation(kvm);
break;
#endif
default:
return -ENODEV;
}
if (atomic_read(&kvm->online_vcpus) > kvm->arch.max_vcpus)
return -E2BIG;
return 0;
}
int kvm_vgic_create(struct kvm *kvm, u32 type)
{
int i, vcpu_lock_idx = -1, ret;
struct kvm_vcpu *vcpu;
mutex_lock(&kvm->lock);
if (irqchip_in_kernel(kvm)) {
ret = -EEXIST;
goto out;
}
/*
* This function is also called by the KVM_CREATE_IRQCHIP handler,
* which had no chance yet to check the availability of the GICv2
* emulation. So check this here again. KVM_CREATE_DEVICE does
* the proper checks already.
*/
if (type == KVM_DEV_TYPE_ARM_VGIC_V2 && !vgic->can_emulate_gicv2) {
ret = -ENODEV;
goto out;
}
/*
* Any time a vcpu is run, vcpu_load is called which tries to grab the
* vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure
* that no other VCPUs are run while we create the vgic.
*/
ret = -EBUSY;
kvm_for_each_vcpu(i, vcpu, kvm) {
if (!mutex_trylock(&vcpu->mutex))
goto out_unlock;
vcpu_lock_idx = i;
}
kvm_for_each_vcpu(i, vcpu, kvm) {
if (vcpu->arch.has_run_once)
goto out_unlock;
}
ret = 0;
ret = init_vgic_model(kvm, type);
if (ret)
goto out_unlock;
spin_lock_init(&kvm->arch.vgic.lock);
kvm->arch.vgic.in_kernel = true;
kvm->arch.vgic.vgic_model = type;
kvm->arch.vgic.vctrl_base = vgic->vctrl_base;
kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
kvm->arch.vgic.vgic_redist_base = VGIC_ADDR_UNDEF;
out_unlock:
for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
mutex_unlock(&vcpu->mutex);
}
out:
mutex_unlock(&kvm->lock);
return ret;
}
static int vgic_ioaddr_overlap(struct kvm *kvm)
{
phys_addr_t dist = kvm->arch.vgic.vgic_dist_base;
phys_addr_t cpu = kvm->arch.vgic.vgic_cpu_base;
if (IS_VGIC_ADDR_UNDEF(dist) || IS_VGIC_ADDR_UNDEF(cpu))
return 0;
if ((dist <= cpu && dist + KVM_VGIC_V2_DIST_SIZE > cpu) ||
(cpu <= dist && cpu + KVM_VGIC_V2_CPU_SIZE > dist))
return -EBUSY;
return 0;
}
static int vgic_ioaddr_assign(struct kvm *kvm, phys_addr_t *ioaddr,
phys_addr_t addr, phys_addr_t size)
{
int ret;
if (addr & ~KVM_PHYS_MASK)
return -E2BIG;
if (addr & (SZ_4K - 1))
return -EINVAL;
if (!IS_VGIC_ADDR_UNDEF(*ioaddr))
return -EEXIST;
if (addr + size < addr)
return -EINVAL;
*ioaddr = addr;
ret = vgic_ioaddr_overlap(kvm);
if (ret)
*ioaddr = VGIC_ADDR_UNDEF;
return ret;
}
/**
* kvm_vgic_addr - set or get vgic VM base addresses
* @kvm: pointer to the vm struct
* @type: the VGIC addr type, one of KVM_VGIC_V[23]_ADDR_TYPE_XXX
* @addr: pointer to address value
* @write: if true set the address in the VM address space, if false read the
* address
*
* Set or get the vgic base addresses for the distributor and the virtual CPU
* interface in the VM physical address space. These addresses are properties
* of the emulated core/SoC and therefore user space initially knows this
* information.
*/
int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
{
int r = 0;
struct vgic_dist *vgic = &kvm->arch.vgic;
int type_needed;
phys_addr_t *addr_ptr, block_size;
phys_addr_t alignment;
mutex_lock(&kvm->lock);
switch (type) {
case KVM_VGIC_V2_ADDR_TYPE_DIST:
type_needed = KVM_DEV_TYPE_ARM_VGIC_V2;
addr_ptr = &vgic->vgic_dist_base;
block_size = KVM_VGIC_V2_DIST_SIZE;
alignment = SZ_4K;
break;
case KVM_VGIC_V2_ADDR_TYPE_CPU:
type_needed = KVM_DEV_TYPE_ARM_VGIC_V2;
addr_ptr = &vgic->vgic_cpu_base;
block_size = KVM_VGIC_V2_CPU_SIZE;
alignment = SZ_4K;
break;
#ifdef CONFIG_ARM_GIC_V3
case KVM_VGIC_V3_ADDR_TYPE_DIST:
type_needed = KVM_DEV_TYPE_ARM_VGIC_V3;
addr_ptr = &vgic->vgic_dist_base;
block_size = KVM_VGIC_V3_DIST_SIZE;
alignment = SZ_64K;
break;
case KVM_VGIC_V3_ADDR_TYPE_REDIST:
type_needed = KVM_DEV_TYPE_ARM_VGIC_V3;
addr_ptr = &vgic->vgic_redist_base;
block_size = KVM_VGIC_V3_REDIST_SIZE;
alignment = SZ_64K;
break;
#endif
default:
r = -ENODEV;
goto out;
}
if (vgic->vgic_model != type_needed) {
r = -ENODEV;
goto out;
}
if (write) {
if (!IS_ALIGNED(*addr, alignment))
r = -EINVAL;
else
r = vgic_ioaddr_assign(kvm, addr_ptr, *addr,
block_size);
} else {
*addr = *addr_ptr;
}
out:
mutex_unlock(&kvm->lock);
return r;
}
int vgic_set_common_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{
int r;
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_ADDR: {
u64 __user *uaddr = (u64 __user *)(long)attr->addr;
u64 addr;
unsigned long type = (unsigned long)attr->attr;
if (copy_from_user(&addr, uaddr, sizeof(addr)))
return -EFAULT;
r = kvm_vgic_addr(dev->kvm, type, &addr, true);
return (r == -ENODEV) ? -ENXIO : r;
}
case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
u32 __user *uaddr = (u32 __user *)(long)attr->addr;
u32 val;
int ret = 0;
if (get_user(val, uaddr))
return -EFAULT;
/*
* We require:
* - at least 32 SPIs on top of the 16 SGIs and 16 PPIs
* - at most 1024 interrupts
* - a multiple of 32 interrupts
*/
if (val < (VGIC_NR_PRIVATE_IRQS + 32) ||
val > VGIC_MAX_IRQS ||
(val & 31))
return -EINVAL;
mutex_lock(&dev->kvm->lock);
if (vgic_ready(dev->kvm) || dev->kvm->arch.vgic.nr_irqs)
ret = -EBUSY;
else
dev->kvm->arch.vgic.nr_irqs = val;
mutex_unlock(&dev->kvm->lock);
return ret;
}
case KVM_DEV_ARM_VGIC_GRP_CTRL: {
switch (attr->attr) {
case KVM_DEV_ARM_VGIC_CTRL_INIT:
r = vgic_init(dev->kvm);
return r;
}
break;
}
}
return -ENXIO;
}
int vgic_get_common_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{
int r = -ENXIO;
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_ADDR: {
u64 __user *uaddr = (u64 __user *)(long)attr->addr;
u64 addr;
unsigned long type = (unsigned long)attr->attr;
r = kvm_vgic_addr(dev->kvm, type, &addr, false);
if (r)
return (r == -ENODEV) ? -ENXIO : r;
if (copy_to_user(uaddr, &addr, sizeof(addr)))
return -EFAULT;
break;
}
case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
u32 __user *uaddr = (u32 __user *)(long)attr->addr;
r = put_user(dev->kvm->arch.vgic.nr_irqs, uaddr);
break;
}
}
return r;
}
int vgic_has_attr_regs(const struct vgic_io_range *ranges, phys_addr_t offset)
{
if (vgic_find_range(ranges, 4, offset))
return 0;
else
return -ENXIO;
}
static void vgic_init_maintenance_interrupt(void *info)
{
enable_percpu_irq(vgic->maint_irq, 0);
}
static int vgic_cpu_notify(struct notifier_block *self,
unsigned long action, void *cpu)
{
switch (action) {
case CPU_STARTING:
case CPU_STARTING_FROZEN:
vgic_init_maintenance_interrupt(NULL);
break;
case CPU_DYING:
case CPU_DYING_FROZEN:
disable_percpu_irq(vgic->maint_irq);
break;
}
return NOTIFY_OK;
}
static struct notifier_block vgic_cpu_nb = {
.notifier_call = vgic_cpu_notify,
};
static const struct of_device_id vgic_ids[] = {
{ .compatible = "arm,cortex-a15-gic", .data = vgic_v2_probe, },
{ .compatible = "arm,cortex-a7-gic", .data = vgic_v2_probe, },
{ .compatible = "arm,gic-400", .data = vgic_v2_probe, },
{ .compatible = "arm,gic-v3", .data = vgic_v3_probe, },
{},
};
int kvm_vgic_hyp_init(void)
{
const struct of_device_id *matched_id;
const int (*vgic_probe)(struct device_node *,const struct vgic_ops **,
const struct vgic_params **);
struct device_node *vgic_node;
int ret;
vgic_node = of_find_matching_node_and_match(NULL,
vgic_ids, &matched_id);
if (!vgic_node) {
kvm_err("error: no compatible GIC node found\n");
return -ENODEV;
}
vgic_probe = matched_id->data;
ret = vgic_probe(vgic_node, &vgic_ops, &vgic);
if (ret)
return ret;
ret = request_percpu_irq(vgic->maint_irq, vgic_maintenance_handler,
"vgic", kvm_get_running_vcpus());
if (ret) {
kvm_err("Cannot register interrupt %d\n", vgic->maint_irq);
return ret;
}
ret = __register_cpu_notifier(&vgic_cpu_nb);
if (ret) {
kvm_err("Cannot register vgic CPU notifier\n");
goto out_free_irq;
}
/* Callback into for arch code for setup */
vgic_arch_setup(vgic);
on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
return 0;
out_free_irq:
free_percpu_irq(vgic->maint_irq, kvm_get_running_vcpus());
return ret;
}
int kvm_irq_map_gsi(struct kvm *kvm,
struct kvm_kernel_irq_routing_entry *entries,
int gsi)
{
return 0;
}
int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin)
{
return pin;
}
int kvm_set_irq(struct kvm *kvm, int irq_source_id,
u32 irq, int level, bool line_status)
{
unsigned int spi = irq + VGIC_NR_PRIVATE_IRQS;
trace_kvm_set_irq(irq, level, irq_source_id);
BUG_ON(!vgic_initialized(kvm));
if (spi > kvm->arch.vgic.nr_irqs)
return -EINVAL;
return kvm_vgic_inject_irq(kvm, 0, spi, level);
}
/* MSI not implemented yet */
int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
struct kvm *kvm, int irq_source_id,
int level, bool line_status)
{
return 0;
}