diff options
| -rw-r--r-- | include/kvm/arm_vgic.h | 16 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-its.c | 399 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio-v3.c | 8 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio.h | 6 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic.c | 12 |
5 files changed, 420 insertions, 21 deletions
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 8609faced83e..61867492d361 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -22,6 +22,7 @@ #include <linux/spinlock.h> #include <linux/types.h> #include <kvm/iodev.h> +#include <linux/list.h> #define VGIC_V3_MAX_CPUS 255 #define VGIC_V2_MAX_CPUS 8 @@ -136,6 +137,21 @@ struct vgic_its { bool enabled; bool initialized; struct vgic_io_device iodev; + + /* These registers correspond to GITS_BASER{0,1} */ + u64 baser_device_table; + u64 baser_coll_table; + + /* Protects the command queue */ + struct mutex cmd_lock; + u64 cbaser; + u32 creadr; + u32 cwriter; + + /* Protects the device and collection lists */ + struct mutex its_lock; + struct list_head device_list; + struct list_head collection_list; }; struct vgic_dist { diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 6b47b3674690..11cfe2f12c6c 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -21,6 +21,7 @@ #include <linux/kvm.h> #include <linux/kvm_host.h> #include <linux/interrupt.h> +#include <linux/list.h> #include <linux/uaccess.h> #include <linux/irqchip/arm-gic-v3.h> @@ -32,6 +33,329 @@ #include "vgic.h" #include "vgic-mmio.h" +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 its_collection *collection; + u32 lpi; + u32 event_id; +}; + +/* + * We only implement 48 bits of PA at the moment, although the ITS + * supports more. Let's be restrictive here. + */ +#define CBASER_ADDRESS(x) ((x) & GENMASK_ULL(47, 12)) + +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; +} + +/* Requires the its_lock to be held. */ +static void its_free_itte(struct kvm *kvm, struct its_itte *itte) +{ + list_del(&itte->itte_list); + kfree(itte); +} + +static int vgic_its_handle_command(struct kvm *kvm, struct vgic_its *its, + u64 *its_cmd) +{ + return -ENODEV; +} + +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, \ @@ -41,12 +365,6 @@ .its_write = wr, \ } -static unsigned long its_mmio_read_raz(struct kvm *kvm, struct vgic_its *its, - gpa_t addr, unsigned int len) -{ - return 0; -} - static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, gpa_t addr, unsigned int len, unsigned long val) { @@ -55,28 +373,28 @@ static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, static struct vgic_register_region its_registers[] = { REGISTER_ITS_DESC(GITS_CTLR, - its_mmio_read_raz, its_mmio_write_wi, 4, + vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, 4, VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_IIDR, - its_mmio_read_raz, its_mmio_write_wi, 4, + vgic_mmio_read_its_iidr, its_mmio_write_wi, 4, VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_TYPER, - its_mmio_read_raz, its_mmio_write_wi, 8, + vgic_mmio_read_its_typer, its_mmio_write_wi, 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_CBASER, - its_mmio_read_raz, its_mmio_write_wi, 8, + vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_CWRITER, - its_mmio_read_raz, its_mmio_write_wi, 8, + vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_CREADR, - its_mmio_read_raz, its_mmio_write_wi, 8, + vgic_mmio_read_its_creadr, its_mmio_write_wi, 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_BASER, - its_mmio_read_raz, its_mmio_write_wi, 0x40, + vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_IDREGS_BASE, - its_mmio_read_raz, its_mmio_write_wi, 0x30, + vgic_mmio_read_its_idregs, its_mmio_write_wi, 0x30, VGIC_ACCESS_32bit), }; @@ -109,6 +427,18 @@ static int vgic_its_init_its(struct kvm *kvm, struct vgic_its *its) 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; @@ -120,12 +450,24 @@ static int vgic_its_create(struct kvm_device *dev, u32 type) 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->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; @@ -133,7 +475,36 @@ static int vgic_its_create(struct kvm_device *dev, u32 type) 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); } diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c index a5c35050c786..84a301d789e0 100644 --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c @@ -23,15 +23,15 @@ #include "vgic-mmio.h" /* extract @num bytes at @offset bytes offset in data */ -static unsigned long extract_bytes(unsigned long data, unsigned int offset, - unsigned int num) +unsigned long extract_bytes(unsigned long data, unsigned int offset, + unsigned int num) { return (data >> (offset * 8)) & GENMASK_ULL(num * 8 - 1, 0); } /* allows updates of any half of a 64-bit register (or the whole thing) */ -static u64 update_64bit_reg(u64 reg, unsigned int offset, unsigned int len, - unsigned long val) +u64 update_64bit_reg(u64 reg, unsigned int offset, unsigned int len, + unsigned long val) { int lower = (offset & 4) * 8; int upper = lower + 8 * len - 1; diff --git a/virt/kvm/arm/vgic/vgic-mmio.h b/virt/kvm/arm/vgic/vgic-mmio.h index 366d66378732..0b3ecf9d100e 100644 --- a/virt/kvm/arm/vgic/vgic-mmio.h +++ b/virt/kvm/arm/vgic/vgic-mmio.h @@ -96,6 +96,12 @@ unsigned long vgic_data_mmio_bus_to_host(const void *val, unsigned int len); void vgic_data_host_to_mmio_bus(void *buf, unsigned int len, unsigned long data); +unsigned long extract_bytes(unsigned long data, unsigned int offset, + unsigned int num); + +u64 update_64bit_reg(u64 reg, unsigned int offset, unsigned int len, + unsigned long val); + unsigned long vgic_mmio_read_raz(struct kvm_vcpu *vcpu, gpa_t addr, unsigned int len); diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c index fb19a554d090..d3ba1b4227e7 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -33,10 +33,16 @@ struct vgic_global __section(.hyp.text) kvm_vgic_global_state; /* * Locking order is always: - * vgic_cpu->ap_list_lock - * vgic_irq->irq_lock + * its->cmd_lock (mutex) + * its->its_lock (mutex) + * vgic_cpu->ap_list_lock + * vgic_irq->irq_lock * - * (that is, always take the ap_list_lock before the struct vgic_irq lock). + * If you need to take multiple locks, always take the upper lock first, + * then the lower ones, e.g. first take the its_lock, then the irq_lock. + * If you are already holding a lock and need to take a higher one, you + * have to drop the lower ranking lock first and re-aquire it after having + * taken the upper one. * * When taking more than one ap_list_lock at the same time, always take the * lowest numbered VCPU's ap_list_lock first, so: |