diff options
Diffstat (limited to 'arch/arm64/kvm/vgic/vgic-its.c')
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-its.c | 2908 |
1 files changed, 2908 insertions, 0 deletions
diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c new file mode 100644 index 0000000000..c420723548 --- /dev/null +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -0,0 +1,2908 @@ +// 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); + if (irq) + vgic_get_irq_kref(irq); + + 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); + vgic_put_irq(kvm, irq); + + 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); +} |