/* * GICv3 ITS emulation * * Copyright (C) 2015,2016 ARM Ltd. * Author: Andre Przywara * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include #include #include #include #include #include #include "vgic.h" #include "vgic-mmio.h" /* * 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 vgic_dist *dist = &kvm->arch.vgic; struct vgic_irq *irq = vgic_get_irq(kvm, NULL, intid), *oldirq; /* In this case there is no put, since we keep the reference. */ if (irq) return irq; irq = kzalloc(sizeof(struct vgic_irq), GFP_KERNEL); if (!irq) return NULL; INIT_LIST_HEAD(&irq->lpi_list); INIT_LIST_HEAD(&irq->ap_list); spin_lock_init(&irq->irq_lock); irq->config = VGIC_CONFIG_EDGE; kref_init(&irq->refcount); irq->intid = intid; spin_lock(&dist->lpi_list_lock); /* * 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: spin_unlock(&dist->lpi_list_lock); return irq; } struct its_device { struct list_head dev_list; /* the head for the list of ITTEs */ struct list_head itt_head; 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_itte { struct list_head itte_list; struct vgic_irq *irq; struct its_collection *collection; u32 lpi; u32 event_id; }; /* * 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_itte *find_itte(struct vgic_its *its, u32 device_id, u32 event_id) { struct its_device *device; struct its_itte *itte; device = find_its_device(its, device_id); if (device == NULL) return NULL; list_for_each_entry(itte, &device->itt_head, itte_list) if (itte->event_id == event_id) return itte; return NULL; } /* To be used as an iterator this macro misses the enclosing parentheses */ #define for_each_lpi_its(dev, itte, its) \ list_for_each_entry(dev, &(its)->device_list, dev_list) \ list_for_each_entry(itte, &(dev)->itt_head, itte_list) /* * We only implement 48 bits of PA at the moment, although the ITS * supports more. Let's be restrictive here. */ #define BASER_ADDRESS(x) ((x) & GENMASK_ULL(47, 16)) #define CBASER_ADDRESS(x) ((x) & GENMASK_ULL(47, 12)) #define PENDBASER_ADDRESS(x) ((x) & GENMASK_ULL(47, 16)) #define PROPBASER_ADDRESS(x) ((x) & GENMASK_ULL(47, 12)) #define GIC_LPI_OFFSET 8192 /* * 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) { u64 propbase = PROPBASER_ADDRESS(kvm->arch.vgic.propbaser); u8 prop; int ret; ret = kvm_read_guest(kvm, propbase + irq->intid - GIC_LPI_OFFSET, &prop, 1); if (ret) return ret; spin_lock(&irq->irq_lock); if (!filter_vcpu || filter_vcpu == irq->target_vcpu) { irq->priority = LPI_PROP_PRIORITY(prop); irq->enabled = LPI_PROP_ENABLE_BIT(prop); vgic_queue_irq_unlock(kvm, irq); } else { spin_unlock(&irq->irq_lock); } return 0; } /* * Create a snapshot of the current LPI list, so that we can enumerate all * LPIs without holding any lock. * Returns the array length and puts the kmalloc'ed array into intid_ptr. */ static int vgic_copy_lpi_list(struct kvm *kvm, u32 **intid_ptr) { struct vgic_dist *dist = &kvm->arch.vgic; struct vgic_irq *irq; u32 *intids; int irq_count = dist->lpi_list_count, i = 0; /* * We use the current value of the list length, which may change * after the kmalloc. We don't care, because the guest shouldn't * change anything while the command handling is still running, * and in the worst case we would miss a new IRQ, which one wouldn't * expect to be covered by this command anyway. */ intids = kmalloc_array(irq_count, sizeof(intids[0]), GFP_KERNEL); if (!intids) return -ENOMEM; spin_lock(&dist->lpi_list_lock); list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { /* We don't need to "get" the IRQ, as we hold the list lock. */ intids[i] = irq->intid; if (++i == irq_count) break; } spin_unlock(&dist->lpi_list_lock); *intid_ptr = intids; return irq_count; } /* * 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_itte(struct kvm *kvm, struct its_itte *itte) { struct kvm_vcpu *vcpu; if (!its_is_collection_mapped(itte->collection)) return; vcpu = kvm_get_vcpu(kvm, itte->collection->target_addr); spin_lock(&itte->irq->irq_lock); itte->irq->target_vcpu = vcpu; spin_unlock(&itte->irq->irq_lock); } /* * 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_itte *itte; for_each_lpi_its(device, itte, its) { if (!itte->collection || coll != itte->collection) continue; update_affinity_itte(kvm, itte); } } static u32 max_lpis_propbaser(u64 propbaser) { int nr_idbits = (propbaser & 0x1f) + 1; return 1U << min(nr_idbits, INTERRUPT_ID_BITS_ITS); } /* * Scan the whole LPI pending table and sync the pending bit in there * 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 = 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; nr_irqs = vgic_copy_lpi_list(vcpu->kvm, &intids); if (nr_irqs < 0) return nr_irqs; for (i = 0; i < nr_irqs; i++) { int byte_offset, bit_nr; u8 pendmask; 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(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]); spin_lock(&irq->irq_lock); irq->pending = pendmask & (1U << bit_nr); vgic_queue_irq_unlock(vcpu->kvm, irq); vgic_put_irq(vcpu->kvm, irq); } kfree(intids); return ret; } 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) { its->enabled = !!(val & GITS_CTLR_ENABLE); } static unsigned long vgic_mmio_read_its_typer(struct kvm *kvm, struct vgic_its *its, gpa_t addr, unsigned int len) { 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 |= 0x0f << GITS_TYPER_DEVBITS_SHIFT; reg |= 0x0f << GITS_TYPER_IDBITS_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) { return (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0); } 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; } /* * 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. */ static void vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its, u32 devid, u32 eventid) { struct its_itte *itte; if (!its->enabled) return; itte = find_itte(its, devid, eventid); /* Triggering an unmapped IRQ gets silently dropped. */ if (itte && its_is_collection_mapped(itte->collection)) { struct kvm_vcpu *vcpu; vcpu = kvm_get_vcpu(kvm, itte->collection->target_addr); if (vcpu && vcpu->arch.vgic_cpu.lpis_enabled) { spin_lock(&itte->irq->irq_lock); itte->irq->pending = true; vgic_queue_irq_unlock(kvm, itte->irq); } } } /* * 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. */ int vgic_its_inject_msi(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 -ENODEV; if (!(msi->flags & KVM_MSI_VALID_DEVID)) return -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 -ENODEV; iodev = container_of(kvm_io_dev, struct vgic_io_device, dev); mutex_lock(&iodev->its->its_lock); vgic_its_trigger_msi(kvm, iodev->its, msi->devid, msi->data); mutex_unlock(&iodev->its->its_lock); return 0; } /* Requires the its_lock to be held. */ static void its_free_itte(struct kvm *kvm, struct its_itte *itte) { list_del(&itte->itte_list); /* This put matches the get in vgic_add_lpi. */ vgic_put_irq(kvm, itte->irq); kfree(itte); } 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_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_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_itte *itte; itte = find_itte(its, device_id, event_id); if (itte && itte->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. */ its_free_itte(kvm, itte); 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_itte *itte; struct its_collection *collection; itte = find_itte(its, device_id, event_id); if (!itte) return E_ITS_MOVI_UNMAPPED_INTERRUPT; if (!its_is_collection_mapped(itte->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; itte->collection = collection; vcpu = kvm_get_vcpu(kvm, collection->target_addr); spin_lock(&itte->irq->irq_lock); itte->irq->target_vcpu = vcpu; spin_unlock(&itte->irq->irq_lock); return 0; } /* * 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 accessbible). * For this we have to read the respective first level entry. */ static bool vgic_its_check_id(struct vgic_its *its, u64 baser, int id) { int l1_tbl_size = GITS_BASER_NR_PAGES(baser) * SZ_64K; int index; u64 indirect_ptr; gfn_t gfn; if (!(baser & GITS_BASER_INDIRECT)) { phys_addr_t addr; if (id >= (l1_tbl_size / GITS_BASER_ENTRY_SIZE(baser))) return false; addr = BASER_ADDRESS(baser) + id * GITS_BASER_ENTRY_SIZE(baser); gfn = addr >> PAGE_SHIFT; return kvm_is_visible_gfn(its->dev->kvm, gfn); } /* calculate and check the index into the 1st level */ index = id / (SZ_64K / GITS_BASER_ENTRY_SIZE(baser)); if (index >= (l1_tbl_size / sizeof(u64))) return false; /* Each 1st level entry is represented by a 64-bit value. */ if (kvm_read_guest(its->dev->kvm, BASER_ADDRESS(baser) + 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. * Any address beyond our supported 48 bits of PA will be caught * by the actual check in the final step. */ indirect_ptr &= GENMASK_ULL(51, 16); /* Find the address of the actual entry */ index = id % (SZ_64K / GITS_BASER_ENTRY_SIZE(baser)); indirect_ptr += index * GITS_BASER_ENTRY_SIZE(baser); gfn = indirect_ptr >> PAGE_SHIFT; return kvm_is_visible_gfn(its->dev->kvm, gfn); } static int vgic_its_alloc_collection(struct vgic_its *its, struct its_collection **colp, u32 coll_id) { struct its_collection *collection; if (!vgic_its_check_id(its, its->baser_coll_table, coll_id)) return E_ITS_MAPC_COLLECTION_OOR; collection = kzalloc(sizeof(*collection), GFP_KERNEL); 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_itte *itte; /* * 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, itte, its) if (itte->collection && itte->collection->collection_id == coll_id) itte->collection = NULL; list_del(&collection->coll_list); kfree(collection); } /* * 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_itte *itte; struct its_device *device; struct its_collection *collection, *new_coll = NULL; int lpi_nr; int ret; device = find_its_device(its, device_id); if (!device) return E_ITS_MAPTI_UNMAPPED_DEVICE; collection = find_collection(its, coll_id); if (!collection) { ret = vgic_its_alloc_collection(its, &collection, coll_id); if (ret) return ret; new_coll = collection; } 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)) { ret = E_ITS_MAPTI_PHYSICALID_OOR; goto err; } itte = find_itte(its, device_id, event_id); if (!itte) { itte = kzalloc(sizeof(struct its_itte), GFP_KERNEL); if (!itte) { ret = -ENOMEM; goto err; } itte->event_id = event_id; list_add_tail(&itte->itte_list, &device->itt_head); } itte->collection = collection; itte->lpi = lpi_nr; itte->irq = vgic_add_lpi(kvm, lpi_nr); update_affinity_itte(kvm, itte); /* * We "cache" the configuration table entries in out 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. */ update_lpi_config(kvm, itte->irq, NULL); return 0; err: if (new_coll) vgic_its_free_collection(its, coll_id); return ret; } /* Requires the its_lock to be held. */ static void vgic_its_unmap_device(struct kvm *kvm, struct its_device *device) { struct its_itte *itte, *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(itte, temp, &device->itt_head, itte_list) its_free_itte(kvm, itte); list_del(&device->dev_list); kfree(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); struct its_device *device; if (!vgic_its_check_id(its, its->baser_device_table, device_id)) return E_ITS_MAPD_DEVICE_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_unmap_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 = kzalloc(sizeof(struct its_device), GFP_KERNEL); if (!device) return -ENOMEM; device->device_id = device_id; INIT_LIST_HEAD(&device->itt_head); list_add_tail(&device->dev_list, &its->device_list); return 0; } /* * 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); } else { collection = find_collection(its, coll_id); if (!collection) { int ret; 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_itte *itte; itte = find_itte(its, device_id, event_id); if (!itte) return E_ITS_CLEAR_UNMAPPED_INTERRUPT; itte->irq->pending = false; return 0; } /* * 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_itte *itte; itte = find_itte(its, device_id, event_id); if (!itte) return E_ITS_INV_UNMAPPED_INTERRUPT; return update_lpi_config(kvm, itte->irq, NULL); } /* * 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; struct vgic_irq *irq; u32 *intids; int irq_count, i; 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); irq_count = vgic_copy_lpi_list(kvm, &intids); if (irq_count < 0) return irq_count; for (i = 0; i < irq_count; i++) { irq = vgic_get_irq(kvm, NULL, intids[i]); if (!irq) continue; update_lpi_config(kvm, irq, vcpu); vgic_put_irq(kvm, irq); } kfree(intids); 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) { struct vgic_dist *dist = &kvm->arch.vgic; 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; 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); spin_lock(&dist->lpi_list_lock); list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { spin_lock(&irq->irq_lock); if (irq->target_vcpu == vcpu1) irq->target_vcpu = vcpu2; spin_unlock(&irq->irq_lock); } spin_unlock(&dist->lpi_list_lock); 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); vgic_its_trigger_msi(kvm, its, msi_devid, msi_data); return 0; } /* * 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); /* Bits 15:12 contain bits 51:48 of the PA, which we don't support. */ reg &= ~GENMASK_ULL(15, 12); /* 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. * Also limit the physical addresses to 48 bits. */ reg &= ~(GENMASK_ULL(51, 48) | 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)) /* * 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) { gpa_t cbaser; u64 cmd_buf[4]; u32 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; cbaser = CBASER_ADDRESS(its->cbaser); while (its->cwriter != its->creadr) { int ret = kvm_read_guest(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; } 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); } #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) { u64 entry_size, device_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 = 8; device_type = GITS_BASER_TYPE_DEVICE; break; case 1: regptr = &its->baser_coll_table; entry_size = 8; device_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 |= device_type << GITS_BASER_TYPE_SHIFT; reg = vgic_sanitise_its_baser(reg); *regptr = reg; } #define REGISTER_ITS_DESC(off, rd, wr, length, acc) \ { \ .reg_offset = off, \ .len = length, \ .access_flags = acc, \ .its_read = rd, \ .its_write = wr, \ } 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(GITS_IIDR, vgic_mmio_read_its_iidr, its_mmio_write_wi, 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(GITS_CREADR, vgic_mmio_read_its_creadr, its_mmio_write_wi, 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_its_init_its(struct kvm *kvm, struct vgic_its *its) { struct vgic_io_device *iodev = &its->iodev; int ret; if (its->initialized) return 0; if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base)) return -ENXIO; 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; mutex_lock(&kvm->slots_lock); ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, iodev->base_addr, KVM_VGIC_V3_ITS_SIZE, &iodev->dev); mutex_unlock(&kvm->slots_lock); if (!ret) its->initialized = true; return ret; } #define INITIAL_BASER_VALUE \ (GIC_BASER_CACHEABILITY(GITS_BASER, INNER, RaWb) | \ GIC_BASER_CACHEABILITY(GITS_BASER, OUTER, SameAsInner) | \ GIC_BASER_SHAREABILITY(GITS_BASER, InnerShareable) | \ ((8ULL - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) | \ 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) { struct vgic_its *its; if (type != KVM_DEV_TYPE_ARM_VGIC_ITS) return -ENODEV; its = kzalloc(sizeof(struct vgic_its), GFP_KERNEL); if (!its) return -ENOMEM; mutex_init(&its->its_lock); mutex_init(&its->cmd_lock); its->vgic_its_base = VGIC_ADDR_UNDEF; INIT_LIST_HEAD(&its->device_list); INIT_LIST_HEAD(&its->collection_list); dev->kvm->arch.vgic.has_its = true; its->initialized = false; 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; return 0; } static void vgic_its_destroy(struct kvm_device *kvm_dev) { struct kvm *kvm = kvm_dev->kvm; struct vgic_its *its = kvm_dev->private; struct its_device *dev; struct its_itte *itte; struct list_head *dev_cur, *dev_temp; struct list_head *cur, *temp; /* * We may end up here without the lists ever having been initialized. * Check this and bail out early to avoid dereferencing a NULL pointer. */ if (!its->device_list.next) return; mutex_lock(&its->its_lock); list_for_each_safe(dev_cur, dev_temp, &its->device_list) { dev = container_of(dev_cur, struct its_device, dev_list); list_for_each_safe(cur, temp, &dev->itt_head) { itte = (container_of(cur, struct its_itte, itte_list)); its_free_itte(kvm, itte); } list_del(dev_cur); kfree(dev); } list_for_each_safe(cur, temp, &its->collection_list) { list_del(cur); kfree(container_of(cur, struct its_collection, coll_list)); } mutex_unlock(&its->its_lock); kfree(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; } break; } return -ENXIO; } 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 (its->initialized) return -EBUSY; if (copy_from_user(&addr, uaddr, sizeof(addr))) return -EFAULT; ret = vgic_check_ioaddr(dev->kvm, &its->vgic_its_base, addr, SZ_64K); if (ret) return ret; its->vgic_its_base = addr; return 0; } case KVM_DEV_ARM_VGIC_GRP_CTRL: switch (attr->attr) { case KVM_DEV_ARM_VGIC_CTRL_INIT: return vgic_its_init_its(dev->kvm, its); } break; } 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; 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); }