// SPDX-License-Identifier: GPL-2.0-only
/*
* GICv3 ITS emulation
*
* Copyright (C) 2015,2016 ARM Ltd.
* Author: Andre Przywara <andre.przywara@arm.com>
*/
#include <linux/cpu.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/uaccess.h>
#include <linux/list_sort.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
#include "vgic.h"
#include "vgic-mmio.h"
static int vgic_its_save_tables_v0(struct vgic_its *its);
static int vgic_its_restore_tables_v0(struct vgic_its *its);
static int vgic_its_commit_v0(struct vgic_its *its);
static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
struct kvm_vcpu *filter_vcpu, bool needs_inv);
/*
* Creates a new (reference to a) struct vgic_irq for a given LPI.
* If this LPI is already mapped on another ITS, we increase its refcount
* and return a pointer to the existing structure.
* If this is a "new" LPI, we allocate and initialize a new struct vgic_irq.
* This function returns a pointer to the _unlocked_ structure.
*/
static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid,
struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_irq *irq = vgic_get_irq(kvm, NULL, intid), *oldirq;
unsigned long flags;
int ret;
/* In this case there is no put, since we keep the reference. */
if (irq)
return irq;
irq = kzalloc(sizeof(struct vgic_irq), GFP_KERNEL_ACCOUNT);
if (!irq)
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&irq->lpi_list);
INIT_LIST_HEAD(&irq->ap_list);
raw_spin_lock_init(&irq->irq_lock);
irq->config = VGIC_CONFIG_EDGE;
kref_init(&irq->refcount);
irq->intid = intid;
irq->target_vcpu = vcpu;
irq->group = 1;
raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
/*
* There could be a race with another vgic_add_lpi(), so we need to
* check that we don't add a second list entry with the same LPI.
*/
list_for_each_entry(oldirq, &dist->lpi_list_head, lpi_list) {
if (oldirq->intid != intid)
continue;
/* Someone was faster with adding this LPI, lets use that. */
kfree(irq);
irq = oldirq;
/*
* This increases the refcount, the caller is expected to
* call vgic_put_irq() on the returned pointer once it's
* finished with the IRQ.
*/
vgic_get_irq_kref(irq);
goto out_unlock;
}
list_add_tail(&irq->lpi_list, &dist->lpi_list_head);
dist->lpi_list_count++;
out_unlock:
raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
/*
* We "cache" the configuration table entries in our struct vgic_irq's.
* However we only have those structs for mapped IRQs, so we read in
* the respective config data from memory here upon mapping the LPI.
*
* Should any of these fail, behave as if we couldn't create the LPI
* by dropping the refcount and returning the error.
*/
ret = update_lpi_config(kvm, irq, NULL, false);
if (ret) {
vgic_put_irq(kvm, irq);
return ERR_PTR(ret);
}
ret = vgic_v3_lpi_sync_pending_status(kvm, irq);
if (ret) {
vgic_put_irq(kvm, irq);
return ERR_PTR(ret);
}
return irq;
}
struct its_device {
struct list_head dev_list;
/* the head for the list of ITTEs */
struct list_head itt_head;
u32 num_eventid_bits;
gpa_t itt_addr;
u32 device_id;
};
#define COLLECTION_NOT_MAPPED ((u32)~0)
struct its_collection {
struct list_head coll_list;
u32 collection_id;
u32 target_addr;
};
#define its_is_collection_mapped(coll) ((coll) && \
((coll)->target_addr != COLLECTION_NOT_MAPPED))
struct its_ite {
struct list_head ite_list;
struct vgic_irq *irq;
struct its_collection *collection;
u32 event_id;
};
struct vgic_translation_cache_entry {
struct list_head entry;
phys_addr_t db;
u32 devid;
u32 eventid;
struct vgic_irq *irq;
};
/**
* struct vgic_its_abi - ITS abi ops and settings
* @cte_esz: collection table entry size
* @dte_esz: device table entry size
* @ite_esz: interrupt translation table entry size
* @save tables: save the ITS tables into guest RAM
* @restore_tables: restore the ITS internal structs from tables
* stored in guest RAM
* @commit: initialize the registers which expose the ABI settings,
* especially the entry sizes
*/
struct vgic_its_abi {
int cte_esz;
int dte_esz;
int ite_esz;
int (*save_tables)(struct vgic_its *its);
int (*restore_tables)(struct vgic_its *its);
int (*commit)(struct vgic_its *its);
};
#define ABI_0_ESZ 8
#define ESZ_MAX ABI_0_ESZ
static const struct vgic_its_abi its_table_abi_versions[] = {
[0] = {
.cte_esz = ABI_0_ESZ,
.dte_esz = ABI_0_ESZ,
.ite_esz = ABI_0_ESZ,
.save_tables = vgic_its_save_tables_v0,
.restore_tables = vgic_its_restore_tables_v0,
.commit = vgic_its_commit_v0,
},
};
#define NR_ITS_ABIS ARRAY_SIZE(its_table_abi_versions)
inline const struct vgic_its_abi *vgic_its_get_abi(struct vgic_its *its)
{
return &its_table_abi_versions[its->abi_rev];
}
static int vgic_its_set_abi(struct vgic_its *its, u32 rev)
{
const struct vgic_its_abi *abi;
its->abi_rev = rev;
abi = vgic_its_get_abi(its);
return abi->commit(its);
}
/*
* Find and returns a device in the device table for an ITS.
* Must be called with the its_lock mutex held.
*/
static struct its_device *find_its_device(struct vgic_its *its, u32 device_id)
{
struct its_device *device;
list_for_each_entry(device, &its->device_list, dev_list)
if (device_id == device->device_id)
return device;
return NULL;
}
/*
* Find and returns an interrupt translation table entry (ITTE) for a given
* Device ID/Event ID pair on an ITS.
* Must be called with the its_lock mutex held.
*/
static struct its_ite *find_ite(struct vgic_its *its, u32 device_id,
u32 event_id)
{
struct its_device *device;
struct its_ite *ite;
device = find_its_device(its, device_id);
if (device == NULL)
return NULL;
list_for_each_entry(ite, &device->itt_head, ite_list)
if (ite->event_id == event_id)
return ite;
return NULL;
}
/* To be used as an iterator this macro misses the enclosing parentheses */
#define for_each_lpi_its(dev, ite, its) \
list_for_each_entry(dev, &(its)->device_list, dev_list) \
list_for_each_entry(ite, &(dev)->itt_head, ite_list)
#define GIC_LPI_OFFSET 8192
#define VITS_TYPER_IDBITS 16
#define VITS_TYPER_DEVBITS 16
#define VITS_DTE_MAX_DEVID_OFFSET (BIT(14) - 1)
#define VITS_ITE_MAX_EVENTID_OFFSET (BIT(16) - 1)
/*
* Finds and returns a collection in the ITS collection table.
* Must be called with the its_lock mutex held.
*/
static struct its_collection *find_collection(struct vgic_its *its, int coll_id)
{
struct its_collection *collection;
list_for_each_entry(collection, &its->collection_list, coll_list) {
if (coll_id == collection->collection_id)
return collection;
}
return NULL;
}
#define LPI_PROP_ENABLE_BIT(p) ((p) & LPI_PROP_ENABLED)
#define LPI_PROP_PRIORITY(p) ((p) & 0xfc)
/*
* Reads the configuration data for a given LPI from guest memory and
* updates the fields in struct vgic_irq.
* If filter_vcpu is not NULL, applies only if the IRQ is targeting this
* VCPU. Unconditionally applies if filter_vcpu is NULL.
*/
static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
struct kvm_vcpu *filter_vcpu, bool needs_inv)
{
u64 propbase = GICR_PROPBASER_ADDRESS(kvm->arch.vgic.propbaser);
u8 prop;
int ret;
unsigned long flags;
ret = kvm_read_guest_lock(kvm, propbase + irq->intid - GIC_LPI_OFFSET,
&prop, 1);
if (ret)
return ret;
raw_spin_lock_irqsave(&irq->irq_lock, flags);
if (!filter_vcpu || filter_vcpu == irq->target_vcpu) {
irq->priority = LPI_PROP_PRIORITY(prop);
irq->enabled = LPI_PROP_ENABLE_BIT(prop);
if (!irq->hw) {
vgic_queue_irq_unlock(kvm, irq, flags);
return 0;
}
}
raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
if (irq->hw)
return its_prop_update_vlpi(irq->host_irq, prop, needs_inv);
return 0;
}
/*
* Create a snapshot of the current LPIs targeting @vcpu, so that we can
* enumerate those LPIs without holding any lock.
* Returns their number and puts the kmalloc'ed array into intid_ptr.
*/
int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_irq *irq;
unsigned long flags;
u32 *intids;
int irq_count, i = 0;
/*
* There is an obvious race between allocating the array and LPIs
* being mapped/unmapped. If we ended up here as a result of a
* command, we're safe (locks are held, preventing another
* command). If coming from another path (such as enabling LPIs),
* we must be careful not to overrun the array.
*/
irq_count = READ_ONCE(dist->lpi_list_count);
intids = kmalloc_array(irq_count, sizeof(intids[0]), GFP_KERNEL_ACCOUNT);
if (!intids)
return -ENOMEM;
raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
if (i == irq_count)
break;
/* We don't need to "get" the IRQ, as we hold the list lock. */
if (vcpu && irq->target_vcpu != vcpu)
continue;
intids[i++] = irq->intid;
}
raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
*intid_ptr = intids;
return i;
}
static int update_affinity(struct vgic_irq *irq, struct kvm_vcpu *vcpu)
{
int ret = 0;
unsigned long flags;
raw_spin_lock_irqsave(&irq->irq_lock, flags);
irq->target_vcpu = vcpu;
raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
if (irq->hw) {
struct its_vlpi_map map;
ret = its_get_vlpi(irq->host_irq, &map);
if (ret)
return ret;
if (map.vpe)
atomic_dec(&map.vpe->vlpi_count);
map.vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
atomic_inc(&map.vpe->vlpi_count);
ret = its_map_vlpi(irq->host_irq, &map);
}
return ret;
}
/*
* Promotes the ITS view of affinity of an ITTE (which redistributor this LPI
* is targeting) to the VGIC's view, which deals with target VCPUs.
* Needs to be called whenever either the collection for a LPIs has
* changed or the collection itself got retargeted.
*/
static void update_affinity_ite(struct kvm *kvm, struct its_ite *ite)
{
struct kvm_vcpu *vcpu;
if (!its_is_collection_mapped(ite->collection))
return;
vcpu = kvm_get_vcpu(kvm, ite->collection->target_addr);
update_affinity(ite->irq, vcpu);
}
/*
* Updates the target VCPU for every LPI targeting this collection.
* Must be called with the its_lock mutex held.
*/
static void update_affinity_collection(struct kvm *kvm, struct vgic_its *its,
struct its_collection *coll)
{
struct its_device *device;
struct its_ite *ite;
for_each_lpi_its(device, ite, its) {
if (ite->collection != coll)
continue;
update_affinity_ite(kvm, ite);
}
}
static u32 max_lpis_propbaser(u64 propbaser)
{
int nr_idbits = (propbaser & 0x1f) + 1;
return 1U << min(nr_idbits, INTERRUPT_ID_BITS_ITS);
}
/*
* Sync the pending table pending bit of LPIs targeting @vcpu
* with our own data structures. This relies on the LPI being
* mapped before.
*/
static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu)
{
gpa_t pendbase = GICR_PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
struct vgic_irq *irq;
int last_byte_offset = -1;
int ret = 0;
u32 *intids;
int nr_irqs, i;
unsigned long flags;
u8 pendmask;
nr_irqs = vgic_copy_lpi_list(vcpu->kvm, vcpu, &intids);
if (nr_irqs < 0)
return nr_irqs;
for (i = 0; i < nr_irqs; i++) {
int byte_offset, bit_nr;
byte_offset = intids[i] / BITS_PER_BYTE;
bit_nr = intids[i] % BITS_PER_BYTE;
/*
* For contiguously allocated LPIs chances are we just read
* this very same byte in the last iteration. Reuse that.
*/
if (byte_offset != last_byte_offset) {
ret = kvm_read_guest_lock(vcpu->kvm,
pendbase + byte_offset,
&pendmask, 1);
if (ret) {
kfree(intids);
return ret;
}
last_byte_offset = byte_offset;
}
irq = vgic_get_irq(vcpu->kvm, NULL, intids[i]);
raw_spin_lock_irqsave(&irq->irq_lock, flags);
irq->pending_latch = pendmask & (1U << bit_nr);
vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
vgic_put_irq(vcpu->kvm, irq);
}
kfree(intids);
return ret;
}
static unsigned long vgic_mmio_read_its_typer(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
u64 reg = GITS_TYPER_PLPIS;
/*
* We use linear CPU numbers for redistributor addressing,
* so GITS_TYPER.PTA is 0.
* Also we force all PROPBASER registers to be the same, so
* CommonLPIAff is 0 as well.
* To avoid memory waste in the guest, we keep the number of IDBits and
* DevBits low - as least for the time being.
*/
reg |= GIC_ENCODE_SZ(VITS_TYPER_DEVBITS, 5) << GITS_TYPER_DEVBITS_SHIFT;
reg |= GIC_ENCODE_SZ(VITS_TYPER_IDBITS, 5) << GITS_TYPER_IDBITS_SHIFT;
reg |= GIC_ENCODE_SZ(abi->ite_esz, 4) << GITS_TYPER_ITT_ENTRY_SIZE_SHIFT;
return extract_bytes(reg, addr & 7, len);
}
static unsigned long vgic_mmio_read_its_iidr(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
u32 val;
val = (its->abi_rev << GITS_IIDR_REV_SHIFT) & GITS_IIDR_REV_MASK;
val |= (PRODUCT_ID_KVM << GITS_IIDR_PRODUCTID_SHIFT) | IMPLEMENTER_ARM;
return val;
}
static int vgic_mmio_uaccess_write_its_iidr(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len,
unsigned long val)
{
u32 rev = GITS_IIDR_REV(val);
if (rev >= NR_ITS_ABIS)
return -EINVAL;
return vgic_its_set_abi(its, rev);
}
static unsigned long vgic_mmio_read_its_idregs(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
switch (addr & 0xffff) {
case GITS_PIDR0:
return 0x92; /* part number, bits[7:0] */
case GITS_PIDR1:
return 0xb4; /* part number, bits[11:8] */
case GITS_PIDR2:
return GIC_PIDR2_ARCH_GICv3 | 0x0b;
case GITS_PIDR4:
return 0x40; /* This is a 64K software visible page */
/* The following are the ID registers for (any) GIC. */
case GITS_CIDR0:
return 0x0d;
case GITS_CIDR1:
return 0xf0;
case GITS_CIDR2:
return 0x05;
case GITS_CIDR3:
return 0xb1;
}
return 0;
}
static struct vgic_irq *__vgic_its_check_cache(struct vgic_dist *dist,
phys_addr_t db,
u32 devid, u32 eventid)
{
struct vgic_translation_cache_entry *cte;
list_for_each_entry(cte, &dist->lpi_translation_cache, entry) {
/*
* If we hit a NULL entry, there is nothing after this
* point.
*/
if (!cte->irq)
break;
if (cte->db != db || cte->devid != devid ||
cte->eventid != eventid)
continue;
/*
* Move this entry to the head, as it is the most
* recently used.
*/
if (!list_is_first(&cte->entry, &dist->lpi_translation_cache))
list_move(&cte->entry, &dist->lpi_translation_cache);
return cte->irq;
}
return NULL;
}
static struct vgic_irq *vgic_its_check_cache(struct kvm *kvm, phys_addr_t db,
u32 devid, u32 eventid)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_irq *irq;
unsigned long flags;
raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
irq = __vgic_its_check_cache(dist, db, devid, eventid);
raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
return irq;
}
static void vgic_its_cache_translation(struct kvm *kvm, struct vgic_its *its,
u32 devid, u32 eventid,
struct vgic_irq *irq)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_translation_cache_entry *cte;
unsigned long flags;
phys_addr_t db;
/* Do not cache a directly injected interrupt */
if (irq->hw)
return;
raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
if (unlikely(list_empty(&dist->lpi_translation_cache)))
goto out;
/*
* We could have raced with another CPU caching the same
* translation behind our back, so let's check it is not in
* already
*/
db = its->vgic_its_base + GITS_TRANSLATER;
if (__vgic_its_check_cache(dist, db, devid, eventid))
goto out;
/* Always reuse the last entry (LRU policy) */
cte = list_last_entry(&dist->lpi_translation_cache,
typeof(*cte), entry);
/*
* Caching the translation implies having an extra reference
* to the interrupt, so drop the potential reference on what
* was in the cache, and increment it on the new interrupt.
*/
if (cte->irq)
__vgic_put_lpi_locked(kvm, cte->irq);
vgic_get_irq_kref(irq);
cte->db = db;
cte->devid = devid;
cte->eventid = eventid;
cte->irq = irq;
/* Move the new translation to the head of the list */
list_move(&cte->entry, &dist->lpi_translation_cache);
out:
raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
}
void vgic_its_invalidate_cache(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_translation_cache_entry *cte;
unsigned long flags;
raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
list_for_each_entry(cte, &dist->lpi_translation_cache, entry) {
/*
* If we hit a NULL entry, there is nothing after this
* point.
*/
if (!cte->irq)
break;
__vgic_put_lpi_locked(kvm, cte->irq);
cte->irq = NULL;
}
raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
}
int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
u32 devid, u32 eventid, struct vgic_irq **irq)
{
struct kvm_vcpu *vcpu;
struct its_ite *ite;
if (!its->enabled)
return -EBUSY;
ite = find_ite(its, devid, eventid);
if (!ite || !its_is_collection_mapped(ite->collection))
return E_ITS_INT_UNMAPPED_INTERRUPT;
vcpu = kvm_get_vcpu(kvm, ite->collection->target_addr);
if (!vcpu)
return E_ITS_INT_UNMAPPED_INTERRUPT;
if (!vgic_lpis_enabled(vcpu))
return -EBUSY;
vgic_its_cache_translation(kvm, its, devid, eventid, ite->irq);
*irq = ite->irq;
return 0;
}
struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi)
{
u64 address;
struct kvm_io_device *kvm_io_dev;
struct vgic_io_device *iodev;
if (!vgic_has_its(kvm))
return ERR_PTR(-ENODEV);
if (!(msi->flags & KVM_MSI_VALID_DEVID))
return ERR_PTR(-EINVAL);
address = (u64)msi->address_hi << 32 | msi->address_lo;
kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address);
if (!kvm_io_dev)
return ERR_PTR(-EINVAL);
if (kvm_io_dev->ops != &kvm_io_gic_ops)
return ERR_PTR(-EINVAL);
iodev = container_of(kvm_io_dev, struct vgic_io_device, dev);
if (iodev->iodev_type != IODEV_ITS)
return ERR_PTR(-EINVAL);
return iodev->its;
}
/*
* Find the target VCPU and the LPI number for a given devid/eventid pair
* and make this IRQ pending, possibly injecting it.
* Must be called with the its_lock mutex held.
* Returns 0 on success, a positive error value for any ITS mapping
* related errors and negative error values for generic errors.
*/
static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
u32 devid, u32 eventid)
{
struct vgic_irq *irq = NULL;
unsigned long flags;
int err;
err = vgic_its_resolve_lpi(kvm, its, devid, eventid, &irq);
if (err)
return err;
if (irq->hw)
return irq_set_irqchip_state(irq->host_irq,
IRQCHIP_STATE_PENDING, true);
raw_spin_lock_irqsave(&irq->irq_lock, flags);
irq->pending_latch = true;
vgic_queue_irq_unlock(kvm, irq, flags);
return 0;
}
int vgic_its_inject_cached_translation(struct kvm *kvm, struct kvm_msi *msi)
{
struct vgic_irq *irq;
unsigned long flags;
phys_addr_t db;
db = (u64)msi->address_hi << 32 | msi->address_lo;
irq = vgic_its_check_cache(kvm, db, msi->devid, msi->data);
if (!irq)
return -EWOULDBLOCK;
raw_spin_lock_irqsave(&irq->irq_lock, flags);
irq->pending_latch = true;
vgic_queue_irq_unlock(kvm, irq, flags);
return 0;
}
/*
* Queries the KVM IO bus framework to get the ITS pointer from the given
* doorbell address.
* We then call vgic_its_trigger_msi() with the decoded data.
* According to the KVM_SIGNAL_MSI API description returns 1 on success.
*/
int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
{
struct vgic_its *its;
int ret;
if (!vgic_its_inject_cached_translation(kvm, msi))
return 1;
its = vgic_msi_to_its(kvm, msi);
if (IS_ERR(its))
return PTR_ERR(its);
mutex_lock(&its->its_lock);
ret = vgic_its_trigger_msi(kvm, its, msi->devid, msi->data);
mutex_unlock(&its->its_lock);
if (ret < 0)
return ret;
/*
* KVM_SIGNAL_MSI demands a return value > 0 for success and 0
* if the guest has blocked the MSI. So we map any LPI mapping
* related error to that.
*/
if (ret)
return 0;
else
return 1;
}
/* Requires the its_lock to be held. */
static void its_free_ite(struct kvm *kvm, struct its_ite *ite)
{
list_del(&ite->ite_list);
/* This put matches the get in vgic_add_lpi. */
if (ite->irq) {
if (ite->irq->hw)
WARN_ON(its_unmap_vlpi(ite->irq->host_irq));
vgic_put_irq(kvm, ite->irq);
}
kfree(ite);
}
static u64 its_cmd_mask_field(u64 *its_cmd, int word, int shift, int size)
{
return (le64_to_cpu(its_cmd[word]) >> shift) & (BIT_ULL(size) - 1);
}
#define its_cmd_get_command(cmd) its_cmd_mask_field(cmd, 0, 0, 8)
#define its_cmd_get_deviceid(cmd) its_cmd_mask_field(cmd, 0, 32, 32)
#define its_cmd_get_size(cmd) (its_cmd_mask_field(cmd, 1, 0, 5) + 1)
#define its_cmd_get_id(cmd) its_cmd_mask_field(cmd, 1, 0, 32)
#define its_cmd_get_physical_id(cmd) its_cmd_mask_field(cmd, 1, 32, 32)
#define its_cmd_get_collection(cmd) its_cmd_mask_field(cmd, 2, 0, 16)
#define its_cmd_get_ittaddr(cmd) (its_cmd_mask_field(cmd, 2, 8, 44) << 8)
#define its_cmd_get_target_addr(cmd) its_cmd_mask_field(cmd, 2, 16, 32)
#define its_cmd_get_validbit(cmd) its_cmd_mask_field(cmd, 2, 63, 1)
/*
* The DISCARD command frees an Interrupt Translation Table Entry (ITTE).
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 device_id = its_cmd_get_deviceid(its_cmd);
u32 event_id = its_cmd_get_id(its_cmd);
struct its_ite *ite;
ite = find_ite(its, device_id, event_id);
if (ite && its_is_collection_mapped(ite->collection)) {
/*
* Though the spec talks about removing the pending state, we
* don't bother here since we clear the ITTE anyway and the
* pending state is a property of the ITTE struct.
*/
vgic_its_invalidate_cache(kvm);
its_free_ite(kvm, ite);
return 0;
}
return E_ITS_DISCARD_UNMAPPED_INTERRUPT;
}
/*
* The MOVI command moves an ITTE to a different collection.
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 device_id = its_cmd_get_deviceid(its_cmd);
u32 event_id = its_cmd_get_id(its_cmd);
u32 coll_id = its_cmd_get_collection(its_cmd);
struct kvm_vcpu *vcpu;
struct its_ite *ite;
struct its_collection *collection;
ite = find_ite(its, device_id, event_id);
if (!ite)
return E_ITS_MOVI_UNMAPPED_INTERRUPT;
if (!its_is_collection_mapped(ite->collection))
return E_ITS_MOVI_UNMAPPED_COLLECTION;
collection = find_collection(its, coll_id);
if (!its_is_collection_mapped(collection))
return E_ITS_MOVI_UNMAPPED_COLLECTION;
ite->collection = collection;
vcpu = kvm_get_vcpu(kvm, collection->target_addr);
vgic_its_invalidate_cache(kvm);
return update_affinity(ite->irq, vcpu);
}
static bool __is_visible_gfn_locked(struct vgic_its *its, gpa_t gpa)
{
gfn_t gfn = gpa >> PAGE_SHIFT;
int idx;
bool ret;
idx = srcu_read_lock(&its->dev->kvm->srcu);
ret = kvm_is_visible_gfn(its->dev->kvm, gfn);
srcu_read_unlock(&its->dev->kvm->srcu, idx);
return ret;
}
/*
* Check whether an ID can be stored into the corresponding guest table.
* For a direct table this is pretty easy, but gets a bit nasty for
* indirect tables. We check whether the resulting guest physical address
* is actually valid (covered by a memslot and guest accessible).
* For this we have to read the respective first level entry.
*/
static bool vgic_its_check_id(struct vgic_its *its, u64 baser, u32 id,
gpa_t *eaddr)
{
int l1_tbl_size = GITS_BASER_NR_PAGES(baser) * SZ_64K;
u64 indirect_ptr, type = GITS_BASER_TYPE(baser);
phys_addr_t base = GITS_BASER_ADDR_48_to_52(baser);
int esz = GITS_BASER_ENTRY_SIZE(baser);
int index;
switch (type) {
case GITS_BASER_TYPE_DEVICE:
if (id >= BIT_ULL(VITS_TYPER_DEVBITS))
return false;
break;
case GITS_BASER_TYPE_COLLECTION:
/* as GITS_TYPER.CIL == 0, ITS supports 16-bit collection ID */
if (id >= BIT_ULL(16))
return false;
break;
default:
return false;
}
if (!(baser & GITS_BASER_INDIRECT)) {
phys_addr_t addr;
if (id >= (l1_tbl_size / esz))
return false;
addr = base + id * esz;
if (eaddr)
*eaddr = addr;
return __is_visible_gfn_locked(its, addr);
}
/* calculate and check the index into the 1st level */
index = id / (SZ_64K / esz);
if (index >= (l1_tbl_size / sizeof(u64)))
return false;
/* Each 1st level entry is represented by a 64-bit value. */
if (kvm_read_guest_lock(its->dev->kvm,
base + index * sizeof(indirect_ptr),
&indirect_ptr, sizeof(indirect_ptr)))
return false;
indirect_ptr = le64_to_cpu(indirect_ptr);
/* check the valid bit of the first level entry */
if (!(indirect_ptr & BIT_ULL(63)))
return false;
/* Mask the guest physical address and calculate the frame number. */
indirect_ptr &= GENMASK_ULL(51, 16);
/* Find the address of the actual entry */
index = id % (SZ_64K / esz);
indirect_ptr += index * esz;
if (eaddr)
*eaddr = indirect_ptr;
return __is_visible_gfn_locked(its, indirect_ptr);
}
/*
* Check whether an event ID can be stored in the corresponding Interrupt
* Translation Table, which starts at device->itt_addr.
*/
static bool vgic_its_check_event_id(struct vgic_its *its, struct its_device *device,
u32 event_id)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
int ite_esz = abi->ite_esz;
gpa_t gpa;
/* max table size is: BIT_ULL(device->num_eventid_bits) * ite_esz */
if (event_id >= BIT_ULL(device->num_eventid_bits))
return false;
gpa = device->itt_addr + event_id * ite_esz;
return __is_visible_gfn_locked(its, gpa);
}
/*
* Add a new collection into the ITS collection table.
* Returns 0 on success, and a negative error value for generic errors.
*/
static int vgic_its_alloc_collection(struct vgic_its *its,
struct its_collection **colp,
u32 coll_id)
{
struct its_collection *collection;
collection = kzalloc(sizeof(*collection), GFP_KERNEL_ACCOUNT);
if (!collection)
return -ENOMEM;
collection->collection_id = coll_id;
collection->target_addr = COLLECTION_NOT_MAPPED;
list_add_tail(&collection->coll_list, &its->collection_list);
*colp = collection;
return 0;
}
static void vgic_its_free_collection(struct vgic_its *its, u32 coll_id)
{
struct its_collection *collection;
struct its_device *device;
struct its_ite *ite;
/*
* Clearing the mapping for that collection ID removes the
* entry from the list. If there wasn't any before, we can
* go home early.
*/
collection = find_collection(its, coll_id);
if (!collection)
return;
for_each_lpi_its(device, ite, its)
if (ite->collection &&
ite->collection->collection_id == coll_id)
ite->collection = NULL;
list_del(&collection->coll_list);
kfree(collection);
}
/* Must be called with its_lock mutex held */
static struct its_ite *vgic_its_alloc_ite(struct its_device *device,
struct its_collection *collection,
u32 event_id)
{
struct its_ite *ite;
ite = kzalloc(sizeof(*ite), GFP_KERNEL_ACCOUNT);
if (!ite)
return ERR_PTR(-ENOMEM);
ite->event_id = event_id;
ite->collection = collection;
list_add_tail(&ite->ite_list, &device->itt_head);
return ite;
}
/*
* The MAPTI and MAPI commands map LPIs to ITTEs.
* Must be called with its_lock mutex held.
*/
static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 device_id = its_cmd_get_deviceid(its_cmd);
u32 event_id = its_cmd_get_id(its_cmd);
u32 coll_id = its_cmd_get_collection(its_cmd);
struct its_ite *ite;
struct kvm_vcpu *vcpu = NULL;
struct its_device *device;
struct its_collection *collection, *new_coll = NULL;
struct vgic_irq *irq;
int lpi_nr;
device = find_its_device(its, device_id);
if (!device)
return E_ITS_MAPTI_UNMAPPED_DEVICE;
if (!vgic_its_check_event_id(its, device, event_id))
return E_ITS_MAPTI_ID_OOR;
if (its_cmd_get_command(its_cmd) == GITS_CMD_MAPTI)
lpi_nr = its_cmd_get_physical_id(its_cmd);
else
lpi_nr = event_id;
if (lpi_nr < GIC_LPI_OFFSET ||
lpi_nr >= max_lpis_propbaser(kvm->arch.vgic.propbaser))
return E_ITS_MAPTI_PHYSICALID_OOR;
/* If there is an existing mapping, behavior is UNPREDICTABLE. */
if (find_ite(its, device_id, event_id))
return 0;
collection = find_collection(its, coll_id);
if (!collection) {
int ret;
if (!vgic_its_check_id(its, its->baser_coll_table, coll_id, NULL))
return E_ITS_MAPC_COLLECTION_OOR;
ret = vgic_its_alloc_collection(its, &collection, coll_id);
if (ret)
return ret;
new_coll = collection;
}
ite = vgic_its_alloc_ite(device, collection, event_id);
if (IS_ERR(ite)) {
if (new_coll)
vgic_its_free_collection(its, coll_id);
return PTR_ERR(ite);
}
if (its_is_collection_mapped(collection))
vcpu = kvm_get_vcpu(kvm, collection->target_addr);
irq = vgic_add_lpi(kvm, lpi_nr, vcpu);
if (IS_ERR(irq)) {
if (new_coll)
vgic_its_free_collection(its, coll_id);
its_free_ite(kvm, ite);
return PTR_ERR(irq);
}
ite->irq = irq;
return 0;
}
/* Requires the its_lock to be held. */
static void vgic_its_free_device(struct kvm *kvm, struct its_device *device)
{
struct its_ite *ite, *temp;
/*
* The spec says that unmapping a device with still valid
* ITTEs associated is UNPREDICTABLE. We remove all ITTEs,
* since we cannot leave the memory unreferenced.
*/
list_for_each_entry_safe(ite, temp, &device->itt_head, ite_list)
its_free_ite(kvm, ite);
vgic_its_invalidate_cache(kvm);
list_del(&device->dev_list);
kfree(device);
}
/* its lock must be held */
static void vgic_its_free_device_list(struct kvm *kvm, struct vgic_its *its)
{
struct its_device *cur, *temp;
list_for_each_entry_safe(cur, temp, &its->device_list, dev_list)
vgic_its_free_device(kvm, cur);
}
/* its lock must be held */
static void vgic_its_free_collection_list(struct kvm *kvm, struct vgic_its *its)
{
struct its_collection *cur, *temp;
list_for_each_entry_safe(cur, temp, &its->collection_list, coll_list)
vgic_its_free_collection(its, cur->collection_id);
}
/* Must be called with its_lock mutex held */
static struct its_device *vgic_its_alloc_device(struct vgic_its *its,
u32 device_id, gpa_t itt_addr,
u8 num_eventid_bits)
{
struct its_device *device;
device = kzalloc(sizeof(*device), GFP_KERNEL_ACCOUNT);
if (!device)
return ERR_PTR(-ENOMEM);
device->device_id = device_id;
device->itt_addr = itt_addr;
device->num_eventid_bits = num_eventid_bits;
INIT_LIST_HEAD(&device->itt_head);
list_add_tail(&device->dev_list, &its->device_list);
return device;
}
/*
* MAPD maps or unmaps a device ID to Interrupt Translation Tables (ITTs).
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 device_id = its_cmd_get_deviceid(its_cmd);
bool valid = its_cmd_get_validbit(its_cmd);
u8 num_eventid_bits = its_cmd_get_size(its_cmd);
gpa_t itt_addr = its_cmd_get_ittaddr(its_cmd);
struct its_device *device;
if (!vgic_its_check_id(its, its->baser_device_table, device_id, NULL))
return E_ITS_MAPD_DEVICE_OOR;
if (valid && num_eventid_bits > VITS_TYPER_IDBITS)
return E_ITS_MAPD_ITTSIZE_OOR;
device = find_its_device(its, device_id);
/*
* The spec says that calling MAPD on an already mapped device
* invalidates all cached data for this device. We implement this
* by removing the mapping and re-establishing it.
*/
if (device)
vgic_its_free_device(kvm, device);
/*
* The spec does not say whether unmapping a not-mapped device
* is an error, so we are done in any case.
*/
if (!valid)
return 0;
device = vgic_its_alloc_device(its, device_id, itt_addr,
num_eventid_bits);
return PTR_ERR_OR_ZERO(device);
}
/*
* The MAPC command maps collection IDs to redistributors.
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_mapc(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u16 coll_id;
u32 target_addr;
struct its_collection *collection;
bool valid;
valid = its_cmd_get_validbit(its_cmd);
coll_id = its_cmd_get_collection(its_cmd);
target_addr = its_cmd_get_target_addr(its_cmd);
if (target_addr >= atomic_read(&kvm->online_vcpus))
return E_ITS_MAPC_PROCNUM_OOR;
if (!valid) {
vgic_its_free_collection(its, coll_id);
vgic_its_invalidate_cache(kvm);
} else {
collection = find_collection(its, coll_id);
if (!collection) {
int ret;
if (!vgic_its_check_id(its, its->baser_coll_table,
coll_id, NULL))
return E_ITS_MAPC_COLLECTION_OOR;
ret = vgic_its_alloc_collection(its, &collection,
coll_id);
if (ret)
return ret;
collection->target_addr = target_addr;
} else {
collection->target_addr = target_addr;
update_affinity_collection(kvm, its, collection);
}
}
return 0;
}
/*
* The CLEAR command removes the pending state for a particular LPI.
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_clear(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 device_id = its_cmd_get_deviceid(its_cmd);
u32 event_id = its_cmd_get_id(its_cmd);
struct its_ite *ite;
ite = find_ite(its, device_id, event_id);
if (!ite)
return E_ITS_CLEAR_UNMAPPED_INTERRUPT;
ite->irq->pending_latch = false;
if (ite->irq->hw)
return irq_set_irqchip_state(ite->irq->host_irq,
IRQCHIP_STATE_PENDING, false);
return 0;
}
int vgic_its_inv_lpi(struct kvm *kvm, struct vgic_irq *irq)
{
return update_lpi_config(kvm, irq, NULL, true);
}
/*
* The INV command syncs the configuration bits from the memory table.
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_inv(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 device_id = its_cmd_get_deviceid(its_cmd);
u32 event_id = its_cmd_get_id(its_cmd);
struct its_ite *ite;
ite = find_ite(its, device_id, event_id);
if (!ite)
return E_ITS_INV_UNMAPPED_INTERRUPT;
return vgic_its_inv_lpi(kvm, ite->irq);
}
/**
* vgic_its_invall - invalidate all LPIs targetting a given vcpu
* @vcpu: the vcpu for which the RD is targetted by an invalidation
*
* Contrary to the INVALL command, this targets a RD instead of a
* collection, and we don't need to hold the its_lock, since no ITS is
* involved here.
*/
int vgic_its_invall(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
int irq_count, i = 0;
u32 *intids;
irq_count = vgic_copy_lpi_list(kvm, vcpu, &intids);
if (irq_count < 0)
return irq_count;
for (i = 0; i < irq_count; i++) {
struct vgic_irq *irq = vgic_get_irq(kvm, NULL, intids[i]);
if (!irq)
continue;
update_lpi_config(kvm, irq, vcpu, false);
vgic_put_irq(kvm, irq);
}
kfree(intids);
if (vcpu->arch.vgic_cpu.vgic_v3.its_vpe.its_vm)
its_invall_vpe(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe);
return 0;
}
/*
* The INVALL command requests flushing of all IRQ data in this collection.
* Find the VCPU mapped to that collection, then iterate over the VM's list
* of mapped LPIs and update the configuration for each IRQ which targets
* the specified vcpu. The configuration will be read from the in-memory
* configuration table.
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_invall(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 coll_id = its_cmd_get_collection(its_cmd);
struct its_collection *collection;
struct kvm_vcpu *vcpu;
collection = find_collection(its, coll_id);
if (!its_is_collection_mapped(collection))
return E_ITS_INVALL_UNMAPPED_COLLECTION;
vcpu = kvm_get_vcpu(kvm, collection->target_addr);
vgic_its_invall(vcpu);
return 0;
}
/*
* The MOVALL command moves the pending state of all IRQs targeting one
* redistributor to another. We don't hold the pending state in the VCPUs,
* but in the IRQs instead, so there is really not much to do for us here.
* However the spec says that no IRQ must target the old redistributor
* afterwards, so we make sure that no LPI is using the associated target_vcpu.
* This command affects all LPIs in the system that target that redistributor.
*/
static int vgic_its_cmd_handle_movall(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 target1_addr = its_cmd_get_target_addr(its_cmd);
u32 target2_addr = its_cmd_mask_field(its_cmd, 3, 16, 32);
struct kvm_vcpu *vcpu1, *vcpu2;
struct vgic_irq *irq;
u32 *intids;
int irq_count, i;
if (target1_addr >= atomic_read(&kvm->online_vcpus) ||
target2_addr >= atomic_read(&kvm->online_vcpus))
return E_ITS_MOVALL_PROCNUM_OOR;
if (target1_addr == target2_addr)
return 0;
vcpu1 = kvm_get_vcpu(kvm, target1_addr);
vcpu2 = kvm_get_vcpu(kvm, target2_addr);
irq_count = vgic_copy_lpi_list(kvm, vcpu1, &intids);
if (irq_count < 0)
return irq_count;
for (i = 0; i < irq_count; i++) {
irq = vgic_get_irq(kvm, NULL, intids[i]);
update_affinity(irq, vcpu2);
vgic_put_irq(kvm, irq);
}
vgic_its_invalidate_cache(kvm);
kfree(intids);
return 0;
}
/*
* The INT command injects the LPI associated with that DevID/EvID pair.
* Must be called with the its_lock mutex held.
*/
static int vgic_its_cmd_handle_int(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
u32 msi_data = its_cmd_get_id(its_cmd);
u64 msi_devid = its_cmd_get_deviceid(its_cmd);
return vgic_its_trigger_msi(kvm, its, msi_devid, msi_data);
}
/*
* This function is called with the its_cmd lock held, but the ITS data
* structure lock dropped.
*/
static int vgic_its_handle_command(struct kvm *kvm, struct vgic_its *its,
u64 *its_cmd)
{
int ret = -ENODEV;
mutex_lock(&its->its_lock);
switch (its_cmd_get_command(its_cmd)) {
case GITS_CMD_MAPD:
ret = vgic_its_cmd_handle_mapd(kvm, its, its_cmd);
break;
case GITS_CMD_MAPC:
ret = vgic_its_cmd_handle_mapc(kvm, its, its_cmd);
break;
case GITS_CMD_MAPI:
ret = vgic_its_cmd_handle_mapi(kvm, its, its_cmd);
break;
case GITS_CMD_MAPTI:
ret = vgic_its_cmd_handle_mapi(kvm, its, its_cmd);
break;
case GITS_CMD_MOVI:
ret = vgic_its_cmd_handle_movi(kvm, its, its_cmd);
break;
case GITS_CMD_DISCARD:
ret = vgic_its_cmd_handle_discard(kvm, its, its_cmd);
break;
case GITS_CMD_CLEAR:
ret = vgic_its_cmd_handle_clear(kvm, its, its_cmd);
break;
case GITS_CMD_MOVALL:
ret = vgic_its_cmd_handle_movall(kvm, its, its_cmd);
break;
case GITS_CMD_INT:
ret = vgic_its_cmd_handle_int(kvm, its, its_cmd);
break;
case GITS_CMD_INV:
ret = vgic_its_cmd_handle_inv(kvm, its, its_cmd);
break;
case GITS_CMD_INVALL:
ret = vgic_its_cmd_handle_invall(kvm, its, its_cmd);
break;
case GITS_CMD_SYNC:
/* we ignore this command: we are in sync all of the time */
ret = 0;
break;
}
mutex_unlock(&its->its_lock);
return ret;
}
static u64 vgic_sanitise_its_baser(u64 reg)
{
reg = vgic_sanitise_field(reg, GITS_BASER_SHAREABILITY_MASK,
GITS_BASER_SHAREABILITY_SHIFT,
vgic_sanitise_shareability);
reg = vgic_sanitise_field(reg, GITS_BASER_INNER_CACHEABILITY_MASK,
GITS_BASER_INNER_CACHEABILITY_SHIFT,
vgic_sanitise_inner_cacheability);
reg = vgic_sanitise_field(reg, GITS_BASER_OUTER_CACHEABILITY_MASK,
GITS_BASER_OUTER_CACHEABILITY_SHIFT,
vgic_sanitise_outer_cacheability);
/* We support only one (ITS) page size: 64K */
reg = (reg & ~GITS_BASER_PAGE_SIZE_MASK) | GITS_BASER_PAGE_SIZE_64K;
return reg;
}
static u64 vgic_sanitise_its_cbaser(u64 reg)
{
reg = vgic_sanitise_field(reg, GITS_CBASER_SHAREABILITY_MASK,
GITS_CBASER_SHAREABILITY_SHIFT,
vgic_sanitise_shareability);
reg = vgic_sanitise_field(reg, GITS_CBASER_INNER_CACHEABILITY_MASK,
GITS_CBASER_INNER_CACHEABILITY_SHIFT,
vgic_sanitise_inner_cacheability);
reg = vgic_sanitise_field(reg, GITS_CBASER_OUTER_CACHEABILITY_MASK,
GITS_CBASER_OUTER_CACHEABILITY_SHIFT,
vgic_sanitise_outer_cacheability);
/* Sanitise the physical address to be 64k aligned. */
reg &= ~GENMASK_ULL(15, 12);
return reg;
}
static unsigned long vgic_mmio_read_its_cbaser(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
return extract_bytes(its->cbaser, addr & 7, len);
}
static void vgic_mmio_write_its_cbaser(struct kvm *kvm, struct vgic_its *its,
gpa_t addr, unsigned int len,
unsigned long val)
{
/* When GITS_CTLR.Enable is 1, this register is RO. */
if (its->enabled)
return;
mutex_lock(&its->cmd_lock);
its->cbaser = update_64bit_reg(its->cbaser, addr & 7, len, val);
its->cbaser = vgic_sanitise_its_cbaser(its->cbaser);
its->creadr = 0;
/*
* CWRITER is architecturally UNKNOWN on reset, but we need to reset
* it to CREADR to make sure we start with an empty command buffer.
*/
its->cwriter = its->creadr;
mutex_unlock(&its->cmd_lock);
}
#define ITS_CMD_BUFFER_SIZE(baser) ((((baser) & 0xff) + 1) << 12)
#define ITS_CMD_SIZE 32
#define ITS_CMD_OFFSET(reg) ((reg) & GENMASK(19, 5))
/* Must be called with the cmd_lock held. */
static void vgic_its_process_commands(struct kvm *kvm, struct vgic_its *its)
{
gpa_t cbaser;
u64 cmd_buf[4];
/* Commands are only processed when the ITS is enabled. */
if (!its->enabled)
return;
cbaser = GITS_CBASER_ADDRESS(its->cbaser);
while (its->cwriter != its->creadr) {
int ret = kvm_read_guest_lock(kvm, cbaser + its->creadr,
cmd_buf, ITS_CMD_SIZE);
/*
* If kvm_read_guest() fails, this could be due to the guest
* programming a bogus value in CBASER or something else going
* wrong from which we cannot easily recover.
* According to section 6.3.2 in the GICv3 spec we can just
* ignore that command then.
*/
if (!ret)
vgic_its_handle_command(kvm, its, cmd_buf);
its->creadr += ITS_CMD_SIZE;
if (its->creadr == ITS_CMD_BUFFER_SIZE(its->cbaser))
its->creadr = 0;
}
}
/*
* By writing to CWRITER the guest announces new commands to be processed.
* To avoid any races in the first place, we take the its_cmd lock, which
* protects our ring buffer variables, so that there is only one user
* per ITS handling commands at a given time.
*/
static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its,
gpa_t addr, unsigned int len,
unsigned long val)
{
u64 reg;
if (!its)
return;
mutex_lock(&its->cmd_lock);
reg = update_64bit_reg(its->cwriter, addr & 7, len, val);
reg = ITS_CMD_OFFSET(reg);
if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) {
mutex_unlock(&its->cmd_lock);
return;
}
its->cwriter = reg;
vgic_its_process_commands(kvm, its);
mutex_unlock(&its->cmd_lock);
}
static unsigned long vgic_mmio_read_its_cwriter(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
return extract_bytes(its->cwriter, addr & 0x7, len);
}
static unsigned long vgic_mmio_read_its_creadr(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
return extract_bytes(its->creadr, addr & 0x7, len);
}
static int vgic_mmio_uaccess_write_its_creadr(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len,
unsigned long val)
{
u32 cmd_offset;
int ret = 0;
mutex_lock(&its->cmd_lock);
if (its->enabled) {
ret = -EBUSY;
goto out;
}
cmd_offset = ITS_CMD_OFFSET(val);
if (cmd_offset >= ITS_CMD_BUFFER_SIZE(its->cbaser)) {
ret = -EINVAL;
goto out;
}
its->creadr = cmd_offset;
out:
mutex_unlock(&its->cmd_lock);
return ret;
}
#define BASER_INDEX(addr) (((addr) / sizeof(u64)) & 0x7)
static unsigned long vgic_mmio_read_its_baser(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
u64 reg;
switch (BASER_INDEX(addr)) {
case 0:
reg = its->baser_device_table;
break;
case 1:
reg = its->baser_coll_table;
break;
default:
reg = 0;
break;
}
return extract_bytes(reg, addr & 7, len);
}
#define GITS_BASER_RO_MASK (GENMASK_ULL(52, 48) | GENMASK_ULL(58, 56))
static void vgic_mmio_write_its_baser(struct kvm *kvm,
struct vgic_its *its,
gpa_t addr, unsigned int len,
unsigned long val)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
u64 entry_size, table_type;
u64 reg, *regptr, clearbits = 0;
/* When GITS_CTLR.Enable is 1, we ignore write accesses. */
if (its->enabled)
return;
switch (BASER_INDEX(addr)) {
case 0:
regptr = &its->baser_device_table;
entry_size = abi->dte_esz;
table_type = GITS_BASER_TYPE_DEVICE;
break;
case 1:
regptr = &its->baser_coll_table;
entry_size = abi->cte_esz;
table_type = GITS_BASER_TYPE_COLLECTION;
clearbits = GITS_BASER_INDIRECT;
break;
default:
return;
}
reg = update_64bit_reg(*regptr, addr & 7, len, val);
reg &= ~GITS_BASER_RO_MASK;
reg &= ~clearbits;
reg |= (entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT;
reg |= table_type << GITS_BASER_TYPE_SHIFT;
reg = vgic_sanitise_its_baser(reg);
*regptr = reg;
if (!(reg & GITS_BASER_VALID)) {
/* Take the its_lock to prevent a race with a save/restore */
mutex_lock(&its->its_lock);
switch (table_type) {
case GITS_BASER_TYPE_DEVICE:
vgic_its_free_device_list(kvm, its);
break;
case GITS_BASER_TYPE_COLLECTION:
vgic_its_free_collection_list(kvm, its);
break;
}
mutex_unlock(&its->its_lock);
}
}
static unsigned long vgic_mmio_read_its_ctlr(struct kvm *vcpu,
struct vgic_its *its,
gpa_t addr, unsigned int len)
{
u32 reg = 0;
mutex_lock(&its->cmd_lock);
if (its->creadr == its->cwriter)
reg |= GITS_CTLR_QUIESCENT;
if (its->enabled)
reg |= GITS_CTLR_ENABLE;
mutex_unlock(&its->cmd_lock);
return reg;
}
static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its,
gpa_t addr, unsigned int len,
unsigned long val)
{
mutex_lock(&its->cmd_lock);
/*
* It is UNPREDICTABLE to enable the ITS if any of the CBASER or
* device/collection BASER are invalid
*/
if (!its->enabled && (val & GITS_CTLR_ENABLE) &&
(!(its->baser_device_table & GITS_BASER_VALID) ||
!(its->baser_coll_table & GITS_BASER_VALID) ||
!(its->cbaser & GITS_CBASER_VALID)))
goto out;
its->enabled = !!(val & GITS_CTLR_ENABLE);
if (!its->enabled)
vgic_its_invalidate_cache(kvm);
/*
* Try to process any pending commands. This function bails out early
* if the ITS is disabled or no commands have been queued.
*/
vgic_its_process_commands(kvm, its);
out:
mutex_unlock(&its->cmd_lock);
}
#define REGISTER_ITS_DESC(off, rd, wr, length, acc) \
{ \
.reg_offset = off, \
.len = length, \
.access_flags = acc, \
.its_read = rd, \
.its_write = wr, \
}
#define REGISTER_ITS_DESC_UACCESS(off, rd, wr, uwr, length, acc)\
{ \
.reg_offset = off, \
.len = length, \
.access_flags = acc, \
.its_read = rd, \
.its_write = wr, \
.uaccess_its_write = uwr, \
}
static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its,
gpa_t addr, unsigned int len, unsigned long val)
{
/* Ignore */
}
static struct vgic_register_region its_registers[] = {
REGISTER_ITS_DESC(GITS_CTLR,
vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, 4,
VGIC_ACCESS_32bit),
REGISTER_ITS_DESC_UACCESS(GITS_IIDR,
vgic_mmio_read_its_iidr, its_mmio_write_wi,
vgic_mmio_uaccess_write_its_iidr, 4,
VGIC_ACCESS_32bit),
REGISTER_ITS_DESC(GITS_TYPER,
vgic_mmio_read_its_typer, its_mmio_write_wi, 8,
VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
REGISTER_ITS_DESC(GITS_CBASER,
vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, 8,
VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
REGISTER_ITS_DESC(GITS_CWRITER,
vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8,
VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
REGISTER_ITS_DESC_UACCESS(GITS_CREADR,
vgic_mmio_read_its_creadr, its_mmio_write_wi,
vgic_mmio_uaccess_write_its_creadr, 8,
VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
REGISTER_ITS_DESC(GITS_BASER,
vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40,
VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
REGISTER_ITS_DESC(GITS_IDREGS_BASE,
vgic_mmio_read_its_idregs, its_mmio_write_wi, 0x30,
VGIC_ACCESS_32bit),
};
/* This is called on setting the LPI enable bit in the redistributor. */
void vgic_enable_lpis(struct kvm_vcpu *vcpu)
{
if (!(vcpu->arch.vgic_cpu.pendbaser & GICR_PENDBASER_PTZ))
its_sync_lpi_pending_table(vcpu);
}
static int vgic_register_its_iodev(struct kvm *kvm, struct vgic_its *its,
u64 addr)
{
struct vgic_io_device *iodev = &its->iodev;
int ret;
mutex_lock(&kvm->slots_lock);
if (!IS_VGIC_ADDR_UNDEF(its->vgic_its_base)) {
ret = -EBUSY;
goto out;
}
its->vgic_its_base = addr;
iodev->regions = its_registers;
iodev->nr_regions = ARRAY_SIZE(its_registers);
kvm_iodevice_init(&iodev->dev, &kvm_io_gic_ops);
iodev->base_addr = its->vgic_its_base;
iodev->iodev_type = IODEV_ITS;
iodev->its = its;
ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, iodev->base_addr,
KVM_VGIC_V3_ITS_SIZE, &iodev->dev);
out:
mutex_unlock(&kvm->slots_lock);
return ret;
}
/* Default is 16 cached LPIs per vcpu */
#define LPI_DEFAULT_PCPU_CACHE_SIZE 16
void vgic_lpi_translation_cache_init(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
unsigned int sz;
int i;
if (!list_empty(&dist->lpi_translation_cache))
return;
sz = atomic_read(&kvm->online_vcpus) * LPI_DEFAULT_PCPU_CACHE_SIZE;
for (i = 0; i < sz; i++) {
struct vgic_translation_cache_entry *cte;
/* An allocation failure is not fatal */
cte = kzalloc(sizeof(*cte), GFP_KERNEL_ACCOUNT);
if (WARN_ON(!cte))
break;
INIT_LIST_HEAD(&cte->entry);
list_add(&cte->entry, &dist->lpi_translation_cache);
}
}
void vgic_lpi_translation_cache_destroy(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_translation_cache_entry *cte, *tmp;
vgic_its_invalidate_cache(kvm);
list_for_each_entry_safe(cte, tmp,
&dist->lpi_translation_cache, entry) {
list_del(&cte->entry);
kfree(cte);
}
}
#define INITIAL_BASER_VALUE \
(GIC_BASER_CACHEABILITY(GITS_BASER, INNER, RaWb) | \
GIC_BASER_CACHEABILITY(GITS_BASER, OUTER, SameAsInner) | \
GIC_BASER_SHAREABILITY(GITS_BASER, InnerShareable) | \
GITS_BASER_PAGE_SIZE_64K)
#define INITIAL_PROPBASER_VALUE \
(GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, RaWb) | \
GIC_BASER_CACHEABILITY(GICR_PROPBASER, OUTER, SameAsInner) | \
GIC_BASER_SHAREABILITY(GICR_PROPBASER, InnerShareable))
static int vgic_its_create(struct kvm_device *dev, u32 type)
{
int ret;
struct vgic_its *its;
if (type != KVM_DEV_TYPE_ARM_VGIC_ITS)
return -ENODEV;
its = kzalloc(sizeof(struct vgic_its), GFP_KERNEL_ACCOUNT);
if (!its)
return -ENOMEM;
mutex_lock(&dev->kvm->arch.config_lock);
if (vgic_initialized(dev->kvm)) {
ret = vgic_v4_init(dev->kvm);
if (ret < 0) {
mutex_unlock(&dev->kvm->arch.config_lock);
kfree(its);
return ret;
}
vgic_lpi_translation_cache_init(dev->kvm);
}
mutex_init(&its->its_lock);
mutex_init(&its->cmd_lock);
/* Yep, even more trickery for lock ordering... */
#ifdef CONFIG_LOCKDEP
mutex_lock(&its->cmd_lock);
mutex_lock(&its->its_lock);
mutex_unlock(&its->its_lock);
mutex_unlock(&its->cmd_lock);
#endif
its->vgic_its_base = VGIC_ADDR_UNDEF;
INIT_LIST_HEAD(&its->device_list);
INIT_LIST_HEAD(&its->collection_list);
dev->kvm->arch.vgic.msis_require_devid = true;
dev->kvm->arch.vgic.has_its = true;
its->enabled = false;
its->dev = dev;
its->baser_device_table = INITIAL_BASER_VALUE |
((u64)GITS_BASER_TYPE_DEVICE << GITS_BASER_TYPE_SHIFT);
its->baser_coll_table = INITIAL_BASER_VALUE |
((u64)GITS_BASER_TYPE_COLLECTION << GITS_BASER_TYPE_SHIFT);
dev->kvm->arch.vgic.propbaser = INITIAL_PROPBASER_VALUE;
dev->private = its;
ret = vgic_its_set_abi(its, NR_ITS_ABIS - 1);
mutex_unlock(&dev->kvm->arch.config_lock);
return ret;
}
static void vgic_its_destroy(struct kvm_device *kvm_dev)
{
struct kvm *kvm = kvm_dev->kvm;
struct vgic_its *its = kvm_dev->private;
mutex_lock(&its->its_lock);
vgic_its_free_device_list(kvm, its);
vgic_its_free_collection_list(kvm, its);
mutex_unlock(&its->its_lock);
kfree(its);
kfree(kvm_dev);/* alloc by kvm_ioctl_create_device, free by .destroy */
}
static int vgic_its_has_attr_regs(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
const struct vgic_register_region *region;
gpa_t offset = attr->attr;
int align;
align = (offset < GITS_TYPER) || (offset >= GITS_PIDR4) ? 0x3 : 0x7;
if (offset & align)
return -EINVAL;
region = vgic_find_mmio_region(its_registers,
ARRAY_SIZE(its_registers),
offset);
if (!region)
return -ENXIO;
return 0;
}
static int vgic_its_attr_regs_access(struct kvm_device *dev,
struct kvm_device_attr *attr,
u64 *reg, bool is_write)
{
const struct vgic_register_region *region;
struct vgic_its *its;
gpa_t addr, offset;
unsigned int len;
int align, ret = 0;
its = dev->private;
offset = attr->attr;
/*
* Although the spec supports upper/lower 32-bit accesses to
* 64-bit ITS registers, the userspace ABI requires 64-bit
* accesses to all 64-bit wide registers. We therefore only
* support 32-bit accesses to GITS_CTLR, GITS_IIDR and GITS ID
* registers
*/
if ((offset < GITS_TYPER) || (offset >= GITS_PIDR4))
align = 0x3;
else
align = 0x7;
if (offset & align)
return -EINVAL;
mutex_lock(&dev->kvm->lock);
if (!lock_all_vcpus(dev->kvm)) {
mutex_unlock(&dev->kvm->lock);
return -EBUSY;
}
mutex_lock(&dev->kvm->arch.config_lock);
if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base)) {
ret = -ENXIO;
goto out;
}
region = vgic_find_mmio_region(its_registers,
ARRAY_SIZE(its_registers),
offset);
if (!region) {
ret = -ENXIO;
goto out;
}
addr = its->vgic_its_base + offset;
len = region->access_flags & VGIC_ACCESS_64bit ? 8 : 4;
if (is_write) {
if (region->uaccess_its_write)
ret = region->uaccess_its_write(dev->kvm, its, addr,
len, *reg);
else
region->its_write(dev->kvm, its, addr, len, *reg);
} else {
*reg = region->its_read(dev->kvm, its, addr, len);
}
out:
mutex_unlock(&dev->kvm->arch.config_lock);
unlock_all_vcpus(dev->kvm);
mutex_unlock(&dev->kvm->lock);
return ret;
}
static u32 compute_next_devid_offset(struct list_head *h,
struct its_device *dev)
{
struct its_device *next;
u32 next_offset;
if (list_is_last(&dev->dev_list, h))
return 0;
next = list_next_entry(dev, dev_list);
next_offset = next->device_id - dev->device_id;
return min_t(u32, next_offset, VITS_DTE_MAX_DEVID_OFFSET);
}
static u32 compute_next_eventid_offset(struct list_head *h, struct its_ite *ite)
{
struct its_ite *next;
u32 next_offset;
if (list_is_last(&ite->ite_list, h))
return 0;
next = list_next_entry(ite, ite_list);
next_offset = next->event_id - ite->event_id;
return min_t(u32, next_offset, VITS_ITE_MAX_EVENTID_OFFSET);
}
/**
* entry_fn_t - Callback called on a table entry restore path
* @its: its handle
* @id: id of the entry
* @entry: pointer to the entry
* @opaque: pointer to an opaque data
*
* Return: < 0 on error, 0 if last element was identified, id offset to next
* element otherwise
*/
typedef int (*entry_fn_t)(struct vgic_its *its, u32 id, void *entry,
void *opaque);
/**
* scan_its_table - Scan a contiguous table in guest RAM and applies a function
* to each entry
*
* @its: its handle
* @base: base gpa of the table
* @size: size of the table in bytes
* @esz: entry size in bytes
* @start_id: the ID of the first entry in the table
* (non zero for 2d level tables)
* @fn: function to apply on each entry
*
* Return: < 0 on error, 0 if last element was identified, 1 otherwise
* (the last element may not be found on second level tables)
*/
static int scan_its_table(struct vgic_its *its, gpa_t base, int size, u32 esz,
int start_id, entry_fn_t fn, void *opaque)
{
struct kvm *kvm = its->dev->kvm;
unsigned long len = size;
int id = start_id;
gpa_t gpa = base;
char entry[ESZ_MAX];
int ret;
memset(entry, 0, esz);
while (true) {
int next_offset;
size_t byte_offset;
ret = kvm_read_guest_lock(kvm, gpa, entry, esz);
if (ret)
return ret;
next_offset = fn(its, id, entry, opaque);
if (next_offset <= 0)
return next_offset;
byte_offset = next_offset * esz;
if (byte_offset >= len)
break;
id += next_offset;
gpa += byte_offset;
len -= byte_offset;
}
return 1;
}
/**
* vgic_its_save_ite - Save an interrupt translation entry at @gpa
*/
static int vgic_its_save_ite(struct vgic_its *its, struct its_device *dev,
struct its_ite *ite, gpa_t gpa, int ite_esz)
{
struct kvm *kvm = its->dev->kvm;
u32 next_offset;
u64 val;
next_offset = compute_next_eventid_offset(&dev->itt_head, ite);
val = ((u64)next_offset << KVM_ITS_ITE_NEXT_SHIFT) |
((u64)ite->irq->intid << KVM_ITS_ITE_PINTID_SHIFT) |
ite->collection->collection_id;
val = cpu_to_le64(val);
return vgic_write_guest_lock(kvm, gpa, &val, ite_esz);
}
/**
* vgic_its_restore_ite - restore an interrupt translation entry
* @event_id: id used for indexing
* @ptr: pointer to the ITE entry
* @opaque: pointer to the its_device
*/
static int vgic_its_restore_ite(struct vgic_its *its, u32 event_id,
void *ptr, void *opaque)
{
struct its_device *dev = opaque;
struct its_collection *collection;
struct kvm *kvm = its->dev->kvm;
struct kvm_vcpu *vcpu = NULL;
u64 val;
u64 *p = (u64 *)ptr;
struct vgic_irq *irq;
u32 coll_id, lpi_id;
struct its_ite *ite;
u32 offset;
val = *p;
val = le64_to_cpu(val);
coll_id = val & KVM_ITS_ITE_ICID_MASK;
lpi_id = (val & KVM_ITS_ITE_PINTID_MASK) >> KVM_ITS_ITE_PINTID_SHIFT;
if (!lpi_id)
return 1; /* invalid entry, no choice but to scan next entry */
if (lpi_id < VGIC_MIN_LPI)
return -EINVAL;
offset = val >> KVM_ITS_ITE_NEXT_SHIFT;
if (event_id + offset >= BIT_ULL(dev->num_eventid_bits))
return -EINVAL;
collection = find_collection(its, coll_id);
if (!collection)
return -EINVAL;
if (!vgic_its_check_event_id(its, dev, event_id))
return -EINVAL;
ite = vgic_its_alloc_ite(dev, collection, event_id);
if (IS_ERR(ite))
return PTR_ERR(ite);
if (its_is_collection_mapped(collection))
vcpu = kvm_get_vcpu(kvm, collection->target_addr);
irq = vgic_add_lpi(kvm, lpi_id, vcpu);
if (IS_ERR(irq)) {
its_free_ite(kvm, ite);
return PTR_ERR(irq);
}
ite->irq = irq;
return offset;
}
static int vgic_its_ite_cmp(void *priv, const struct list_head *a,
const struct list_head *b)
{
struct its_ite *itea = container_of(a, struct its_ite, ite_list);
struct its_ite *iteb = container_of(b, struct its_ite, ite_list);
if (itea->event_id < iteb->event_id)
return -1;
else
return 1;
}
static int vgic_its_save_itt(struct vgic_its *its, struct its_device *device)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
gpa_t base = device->itt_addr;
struct its_ite *ite;
int ret;
int ite_esz = abi->ite_esz;
list_sort(NULL, &device->itt_head, vgic_its_ite_cmp);
list_for_each_entry(ite, &device->itt_head, ite_list) {
gpa_t gpa = base + ite->event_id * ite_esz;
/*
* If an LPI carries the HW bit, this means that this
* interrupt is controlled by GICv4, and we do not
* have direct access to that state without GICv4.1.
* Let's simply fail the save operation...
*/
if (ite->irq->hw && !kvm_vgic_global_state.has_gicv4_1)
return -EACCES;
ret = vgic_its_save_ite(its, device, ite, gpa, ite_esz);
if (ret)
return ret;
}
return 0;
}
/**
* vgic_its_restore_itt - restore the ITT of a device
*
* @its: its handle
* @dev: device handle
*
* Return 0 on success, < 0 on error
*/
static int vgic_its_restore_itt(struct vgic_its *its, struct its_device *dev)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
gpa_t base = dev->itt_addr;
int ret;
int ite_esz = abi->ite_esz;
size_t max_size = BIT_ULL(dev->num_eventid_bits) * ite_esz;
ret = scan_its_table(its, base, max_size, ite_esz, 0,
vgic_its_restore_ite, dev);
/* scan_its_table returns +1 if all ITEs are invalid */
if (ret > 0)
ret = 0;
return ret;
}
/**
* vgic_its_save_dte - Save a device table entry at a given GPA
*
* @its: ITS handle
* @dev: ITS device
* @ptr: GPA
*/
static int vgic_its_save_dte(struct vgic_its *its, struct its_device *dev,
gpa_t ptr, int dte_esz)
{
struct kvm *kvm = its->dev->kvm;
u64 val, itt_addr_field;
u32 next_offset;
itt_addr_field = dev->itt_addr >> 8;
next_offset = compute_next_devid_offset(&its->device_list, dev);
val = (1ULL << KVM_ITS_DTE_VALID_SHIFT |
((u64)next_offset << KVM_ITS_DTE_NEXT_SHIFT) |
(itt_addr_field << KVM_ITS_DTE_ITTADDR_SHIFT) |
(dev->num_eventid_bits - 1));
val = cpu_to_le64(val);
return vgic_write_guest_lock(kvm, ptr, &val, dte_esz);
}
/**
* vgic_its_restore_dte - restore a device table entry
*
* @its: its handle
* @id: device id the DTE corresponds to
* @ptr: kernel VA where the 8 byte DTE is located
* @opaque: unused
*
* Return: < 0 on error, 0 if the dte is the last one, id offset to the
* next dte otherwise
*/
static int vgic_its_restore_dte(struct vgic_its *its, u32 id,
void *ptr, void *opaque)
{
struct its_device *dev;
u64 baser = its->baser_device_table;
gpa_t itt_addr;
u8 num_eventid_bits;
u64 entry = *(u64 *)ptr;
bool valid;
u32 offset;
int ret;
entry = le64_to_cpu(entry);
valid = entry >> KVM_ITS_DTE_VALID_SHIFT;
num_eventid_bits = (entry & KVM_ITS_DTE_SIZE_MASK) + 1;
itt_addr = ((entry & KVM_ITS_DTE_ITTADDR_MASK)
>> KVM_ITS_DTE_ITTADDR_SHIFT) << 8;
if (!valid)
return 1;
/* dte entry is valid */
offset = (entry & KVM_ITS_DTE_NEXT_MASK) >> KVM_ITS_DTE_NEXT_SHIFT;
if (!vgic_its_check_id(its, baser, id, NULL))
return -EINVAL;
dev = vgic_its_alloc_device(its, id, itt_addr, num_eventid_bits);
if (IS_ERR(dev))
return PTR_ERR(dev);
ret = vgic_its_restore_itt(its, dev);
if (ret) {
vgic_its_free_device(its->dev->kvm, dev);
return ret;
}
return offset;
}
static int vgic_its_device_cmp(void *priv, const struct list_head *a,
const struct list_head *b)
{
struct its_device *deva = container_of(a, struct its_device, dev_list);
struct its_device *devb = container_of(b, struct its_device, dev_list);
if (deva->device_id < devb->device_id)
return -1;
else
return 1;
}
/**
* vgic_its_save_device_tables - Save the device table and all ITT
* into guest RAM
*
* L1/L2 handling is hidden by vgic_its_check_id() helper which directly
* returns the GPA of the device entry
*/
static int vgic_its_save_device_tables(struct vgic_its *its)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
u64 baser = its->baser_device_table;
struct its_device *dev;
int dte_esz = abi->dte_esz;
if (!(baser & GITS_BASER_VALID))
return 0;
list_sort(NULL, &its->device_list, vgic_its_device_cmp);
list_for_each_entry(dev, &its->device_list, dev_list) {
int ret;
gpa_t eaddr;
if (!vgic_its_check_id(its, baser,
dev->device_id, &eaddr))
return -EINVAL;
ret = vgic_its_save_itt(its, dev);
if (ret)
return ret;
ret = vgic_its_save_dte(its, dev, eaddr, dte_esz);
if (ret)
return ret;
}
return 0;
}
/**
* handle_l1_dte - callback used for L1 device table entries (2 stage case)
*
* @its: its handle
* @id: index of the entry in the L1 table
* @addr: kernel VA
* @opaque: unused
*
* L1 table entries are scanned by steps of 1 entry
* Return < 0 if error, 0 if last dte was found when scanning the L2
* table, +1 otherwise (meaning next L1 entry must be scanned)
*/
static int handle_l1_dte(struct vgic_its *its, u32 id, void *addr,
void *opaque)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
int l2_start_id = id * (SZ_64K / abi->dte_esz);
u64 entry = *(u64 *)addr;
int dte_esz = abi->dte_esz;
gpa_t gpa;
int ret;
entry = le64_to_cpu(entry);
if (!(entry & KVM_ITS_L1E_VALID_MASK))
return 1;
gpa = entry & KVM_ITS_L1E_ADDR_MASK;
ret = scan_its_table(its, gpa, SZ_64K, dte_esz,
l2_start_id, vgic_its_restore_dte, NULL);
return ret;
}
/**
* vgic_its_restore_device_tables - Restore the device table and all ITT
* from guest RAM to internal data structs
*/
static int vgic_its_restore_device_tables(struct vgic_its *its)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
u64 baser = its->baser_device_table;
int l1_esz, ret;
int l1_tbl_size = GITS_BASER_NR_PAGES(baser) * SZ_64K;
gpa_t l1_gpa;
if (!(baser & GITS_BASER_VALID))
return 0;
l1_gpa = GITS_BASER_ADDR_48_to_52(baser);
if (baser & GITS_BASER_INDIRECT) {
l1_esz = GITS_LVL1_ENTRY_SIZE;
ret = scan_its_table(its, l1_gpa, l1_tbl_size, l1_esz, 0,
handle_l1_dte, NULL);
} else {
l1_esz = abi->dte_esz;
ret = scan_its_table(its, l1_gpa, l1_tbl_size, l1_esz, 0,
vgic_its_restore_dte, NULL);
}
/* scan_its_table returns +1 if all entries are invalid */
if (ret > 0)
ret = 0;
if (ret < 0)
vgic_its_free_device_list(its->dev->kvm, its);
return ret;
}
static int vgic_its_save_cte(struct vgic_its *its,
struct its_collection *collection,
gpa_t gpa, int esz)
{
u64 val;
val = (1ULL << KVM_ITS_CTE_VALID_SHIFT |
((u64)collection->target_addr << KVM_ITS_CTE_RDBASE_SHIFT) |
collection->collection_id);
val = cpu_to_le64(val);
return vgic_write_guest_lock(its->dev->kvm, gpa, &val, esz);
}
/*
* Restore a collection entry into the ITS collection table.
* Return +1 on success, 0 if the entry was invalid (which should be
* interpreted as end-of-table), and a negative error value for generic errors.
*/
static int vgic_its_restore_cte(struct vgic_its *its, gpa_t gpa, int esz)
{
struct its_collection *collection;
struct kvm *kvm = its->dev->kvm;
u32 target_addr, coll_id;
u64 val;
int ret;
BUG_ON(esz > sizeof(val));
ret = kvm_read_guest_lock(kvm, gpa, &val, esz);
if (ret)
return ret;
val = le64_to_cpu(val);
if (!(val & KVM_ITS_CTE_VALID_MASK))
return 0;
target_addr = (u32)(val >> KVM_ITS_CTE_RDBASE_SHIFT);
coll_id = val & KVM_ITS_CTE_ICID_MASK;
if (target_addr != COLLECTION_NOT_MAPPED &&
target_addr >= atomic_read(&kvm->online_vcpus))
return -EINVAL;
collection = find_collection(its, coll_id);
if (collection)
return -EEXIST;
if (!vgic_its_check_id(its, its->baser_coll_table, coll_id, NULL))
return -EINVAL;
ret = vgic_its_alloc_collection(its, &collection, coll_id);
if (ret)
return ret;
collection->target_addr = target_addr;
return 1;
}
/**
* vgic_its_save_collection_table - Save the collection table into
* guest RAM
*/
static int vgic_its_save_collection_table(struct vgic_its *its)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
u64 baser = its->baser_coll_table;
gpa_t gpa = GITS_BASER_ADDR_48_to_52(baser);
struct its_collection *collection;
u64 val;
size_t max_size, filled = 0;
int ret, cte_esz = abi->cte_esz;
if (!(baser & GITS_BASER_VALID))
return 0;
max_size = GITS_BASER_NR_PAGES(baser) * SZ_64K;
list_for_each_entry(collection, &its->collection_list, coll_list) {
ret = vgic_its_save_cte(its, collection, gpa, cte_esz);
if (ret)
return ret;
gpa += cte_esz;
filled += cte_esz;
}
if (filled == max_size)
return 0;
/*
* table is not fully filled, add a last dummy element
* with valid bit unset
*/
val = 0;
BUG_ON(cte_esz > sizeof(val));
ret = vgic_write_guest_lock(its->dev->kvm, gpa, &val, cte_esz);
return ret;
}
/**
* vgic_its_restore_collection_table - reads the collection table
* in guest memory and restores the ITS internal state. Requires the
* BASER registers to be restored before.
*/
static int vgic_its_restore_collection_table(struct vgic_its *its)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
u64 baser = its->baser_coll_table;
int cte_esz = abi->cte_esz;
size_t max_size, read = 0;
gpa_t gpa;
int ret;
if (!(baser & GITS_BASER_VALID))
return 0;
gpa = GITS_BASER_ADDR_48_to_52(baser);
max_size = GITS_BASER_NR_PAGES(baser) * SZ_64K;
while (read < max_size) {
ret = vgic_its_restore_cte(its, gpa, cte_esz);
if (ret <= 0)
break;
gpa += cte_esz;
read += cte_esz;
}
if (ret > 0)
return 0;
if (ret < 0)
vgic_its_free_collection_list(its->dev->kvm, its);
return ret;
}
/**
* vgic_its_save_tables_v0 - Save the ITS tables into guest ARM
* according to v0 ABI
*/
static int vgic_its_save_tables_v0(struct vgic_its *its)
{
int ret;
ret = vgic_its_save_device_tables(its);
if (ret)
return ret;
return vgic_its_save_collection_table(its);
}
/**
* vgic_its_restore_tables_v0 - Restore the ITS tables from guest RAM
* to internal data structs according to V0 ABI
*
*/
static int vgic_its_restore_tables_v0(struct vgic_its *its)
{
int ret;
ret = vgic_its_restore_collection_table(its);
if (ret)
return ret;
ret = vgic_its_restore_device_tables(its);
if (ret)
vgic_its_free_collection_list(its->dev->kvm, its);
return ret;
}
static int vgic_its_commit_v0(struct vgic_its *its)
{
const struct vgic_its_abi *abi;
abi = vgic_its_get_abi(its);
its->baser_coll_table &= ~GITS_BASER_ENTRY_SIZE_MASK;
its->baser_device_table &= ~GITS_BASER_ENTRY_SIZE_MASK;
its->baser_coll_table |= (GIC_ENCODE_SZ(abi->cte_esz, 5)
<< GITS_BASER_ENTRY_SIZE_SHIFT);
its->baser_device_table |= (GIC_ENCODE_SZ(abi->dte_esz, 5)
<< GITS_BASER_ENTRY_SIZE_SHIFT);
return 0;
}
static void vgic_its_reset(struct kvm *kvm, struct vgic_its *its)
{
/* We need to keep the ABI specific field values */
its->baser_coll_table &= ~GITS_BASER_VALID;
its->baser_device_table &= ~GITS_BASER_VALID;
its->cbaser = 0;
its->creadr = 0;
its->cwriter = 0;
its->enabled = 0;
vgic_its_free_device_list(kvm, its);
vgic_its_free_collection_list(kvm, its);
}
static int vgic_its_has_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_ADDR:
switch (attr->attr) {
case KVM_VGIC_ITS_ADDR_TYPE:
return 0;
}
break;
case KVM_DEV_ARM_VGIC_GRP_CTRL:
switch (attr->attr) {
case KVM_DEV_ARM_VGIC_CTRL_INIT:
return 0;
case KVM_DEV_ARM_ITS_CTRL_RESET:
return 0;
case KVM_DEV_ARM_ITS_SAVE_TABLES:
return 0;
case KVM_DEV_ARM_ITS_RESTORE_TABLES:
return 0;
}
break;
case KVM_DEV_ARM_VGIC_GRP_ITS_REGS:
return vgic_its_has_attr_regs(dev, attr);
}
return -ENXIO;
}
static int vgic_its_ctrl(struct kvm *kvm, struct vgic_its *its, u64 attr)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
int ret = 0;
if (attr == KVM_DEV_ARM_VGIC_CTRL_INIT) /* Nothing to do */
return 0;
mutex_lock(&kvm->lock);
if (!lock_all_vcpus(kvm)) {
mutex_unlock(&kvm->lock);
return -EBUSY;
}
mutex_lock(&kvm->arch.config_lock);
mutex_lock(&its->its_lock);
switch (attr) {
case KVM_DEV_ARM_ITS_CTRL_RESET:
vgic_its_reset(kvm, its);
break;
case KVM_DEV_ARM_ITS_SAVE_TABLES:
ret = abi->save_tables(its);
break;
case KVM_DEV_ARM_ITS_RESTORE_TABLES:
ret = abi->restore_tables(its);
break;
}
mutex_unlock(&its->its_lock);
mutex_unlock(&kvm->arch.config_lock);
unlock_all_vcpus(kvm);
mutex_unlock(&kvm->lock);
return ret;
}
/*
* kvm_arch_allow_write_without_running_vcpu - allow writing guest memory
* without the running VCPU when dirty ring is enabled.
*
* The running VCPU is required to track dirty guest pages when dirty ring
* is enabled. Otherwise, the backup bitmap should be used to track the
* dirty guest pages. When vgic/its tables are being saved, the backup
* bitmap is used to track the dirty guest pages due to the missed running
* VCPU in the period.
*/
bool kvm_arch_allow_write_without_running_vcpu(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
return dist->table_write_in_progress;
}
static int vgic_its_set_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
struct vgic_its *its = dev->private;
int ret;
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_ADDR: {
u64 __user *uaddr = (u64 __user *)(long)attr->addr;
unsigned long type = (unsigned long)attr->attr;
u64 addr;
if (type != KVM_VGIC_ITS_ADDR_TYPE)
return -ENODEV;
if (copy_from_user(&addr, uaddr, sizeof(addr)))
return -EFAULT;
ret = vgic_check_iorange(dev->kvm, its->vgic_its_base,
addr, SZ_64K, KVM_VGIC_V3_ITS_SIZE);
if (ret)
return ret;
return vgic_register_its_iodev(dev->kvm, its, addr);
}
case KVM_DEV_ARM_VGIC_GRP_CTRL:
return vgic_its_ctrl(dev->kvm, its, attr->attr);
case KVM_DEV_ARM_VGIC_GRP_ITS_REGS: {
u64 __user *uaddr = (u64 __user *)(long)attr->addr;
u64 reg;
if (get_user(reg, uaddr))
return -EFAULT;
return vgic_its_attr_regs_access(dev, attr, ®, true);
}
}
return -ENXIO;
}
static int vgic_its_get_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_ADDR: {
struct vgic_its *its = dev->private;
u64 addr = its->vgic_its_base;
u64 __user *uaddr = (u64 __user *)(long)attr->addr;
unsigned long type = (unsigned long)attr->attr;
if (type != KVM_VGIC_ITS_ADDR_TYPE)
return -ENODEV;
if (copy_to_user(uaddr, &addr, sizeof(addr)))
return -EFAULT;
break;
}
case KVM_DEV_ARM_VGIC_GRP_ITS_REGS: {
u64 __user *uaddr = (u64 __user *)(long)attr->addr;
u64 reg;
int ret;
ret = vgic_its_attr_regs_access(dev, attr, ®, false);
if (ret)
return ret;
return put_user(reg, uaddr);
}
default:
return -ENXIO;
}
return 0;
}
static struct kvm_device_ops kvm_arm_vgic_its_ops = {
.name = "kvm-arm-vgic-its",
.create = vgic_its_create,
.destroy = vgic_its_destroy,
.set_attr = vgic_its_set_attr,
.get_attr = vgic_its_get_attr,
.has_attr = vgic_its_has_attr,
};
int kvm_vgic_register_its_device(void)
{
return kvm_register_device_ops(&kvm_arm_vgic_its_ops,
KVM_DEV_TYPE_ARM_VGIC_ITS);
}