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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/riscv/kvm | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/riscv/kvm/Kconfig | 36 | ||||
-rw-r--r-- | arch/riscv/kvm/Makefile | 27 | ||||
-rw-r--r-- | arch/riscv/kvm/main.c | 129 | ||||
-rw-r--r-- | arch/riscv/kvm/mmu.c | 802 | ||||
-rw-r--r-- | arch/riscv/kvm/tlb.c | 402 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu.c | 1091 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_exit.c | 212 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_fp.c | 165 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_insn.c | 751 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_sbi.c | 180 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_sbi_base.c | 100 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_sbi_hsm.c | 119 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_sbi_replace.c | 174 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_sbi_v01.c | 118 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_switch.S | 408 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_timer.c | 362 | ||||
-rw-r--r-- | arch/riscv/kvm/vm.c | 94 | ||||
-rw-r--r-- | arch/riscv/kvm/vmid.c | 124 |
18 files changed, 5294 insertions, 0 deletions
diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig new file mode 100644 index 000000000..f36a737d5 --- /dev/null +++ b/arch/riscv/kvm/Kconfig @@ -0,0 +1,36 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# KVM configuration +# + +source "virt/kvm/Kconfig" + +menuconfig VIRTUALIZATION + bool "Virtualization" + help + Say Y here to get to see options for using your Linux host to run + other operating systems inside virtual machines (guests). + This option alone does not add any kernel code. + + If you say N, all options in this submenu will be skipped and + disabled. + +if VIRTUALIZATION + +config KVM + tristate "Kernel-based Virtual Machine (KVM) support (EXPERIMENTAL)" + depends on RISCV_SBI && MMU + select MMU_NOTIFIER + select PREEMPT_NOTIFIERS + select KVM_MMIO + select KVM_GENERIC_DIRTYLOG_READ_PROTECT + select KVM_XFER_TO_GUEST_WORK + select HAVE_KVM_VCPU_ASYNC_IOCTL + select HAVE_KVM_EVENTFD + select SRCU + help + Support hosting virtualized guest machines. + + If unsure, say N. + +endif # VIRTUALIZATION diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile new file mode 100644 index 000000000..019df9208 --- /dev/null +++ b/arch/riscv/kvm/Makefile @@ -0,0 +1,27 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for RISC-V KVM support +# + +ccflags-y += -I $(srctree)/$(src) + +include $(srctree)/virt/kvm/Makefile.kvm + +obj-$(CONFIG_KVM) += kvm.o + +kvm-y += main.o +kvm-y += vm.o +kvm-y += vmid.o +kvm-y += tlb.o +kvm-y += mmu.o +kvm-y += vcpu.o +kvm-y += vcpu_exit.o +kvm-y += vcpu_fp.o +kvm-y += vcpu_insn.o +kvm-y += vcpu_switch.o +kvm-y += vcpu_sbi.o +kvm-$(CONFIG_RISCV_SBI_V01) += vcpu_sbi_v01.o +kvm-y += vcpu_sbi_base.o +kvm-y += vcpu_sbi_replace.o +kvm-y += vcpu_sbi_hsm.o +kvm-y += vcpu_timer.o diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c new file mode 100644 index 000000000..62eedad7e --- /dev/null +++ b/arch/riscv/kvm/main.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/hwcap.h> +#include <asm/sbi.h> + +long kvm_arch_dev_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + return -EINVAL; +} + +int kvm_arch_check_processor_compat(void *opaque) +{ + return 0; +} + +int kvm_arch_hardware_setup(void *opaque) +{ + return 0; +} + +int kvm_arch_hardware_enable(void) +{ + unsigned long hideleg, hedeleg; + + hedeleg = 0; + hedeleg |= (1UL << EXC_INST_MISALIGNED); + hedeleg |= (1UL << EXC_BREAKPOINT); + hedeleg |= (1UL << EXC_SYSCALL); + hedeleg |= (1UL << EXC_INST_PAGE_FAULT); + hedeleg |= (1UL << EXC_LOAD_PAGE_FAULT); + hedeleg |= (1UL << EXC_STORE_PAGE_FAULT); + csr_write(CSR_HEDELEG, hedeleg); + + hideleg = 0; + hideleg |= (1UL << IRQ_VS_SOFT); + hideleg |= (1UL << IRQ_VS_TIMER); + hideleg |= (1UL << IRQ_VS_EXT); + csr_write(CSR_HIDELEG, hideleg); + + csr_write(CSR_HCOUNTEREN, -1UL); + + csr_write(CSR_HVIP, 0); + + return 0; +} + +void kvm_arch_hardware_disable(void) +{ + /* + * After clearing the hideleg CSR, the host kernel will receive + * spurious interrupts if hvip CSR has pending interrupts and the + * corresponding enable bits in vsie CSR are asserted. To avoid it, + * hvip CSR and vsie CSR must be cleared before clearing hideleg CSR. + */ + csr_write(CSR_VSIE, 0); + csr_write(CSR_HVIP, 0); + csr_write(CSR_HEDELEG, 0); + csr_write(CSR_HIDELEG, 0); +} + +int kvm_arch_init(void *opaque) +{ + const char *str; + + if (!riscv_isa_extension_available(NULL, h)) { + kvm_info("hypervisor extension not available\n"); + return -ENODEV; + } + + if (sbi_spec_is_0_1()) { + kvm_info("require SBI v0.2 or higher\n"); + return -ENODEV; + } + + if (!sbi_probe_extension(SBI_EXT_RFENCE)) { + kvm_info("require SBI RFENCE extension\n"); + return -ENODEV; + } + + kvm_riscv_gstage_mode_detect(); + + kvm_riscv_gstage_vmid_detect(); + + kvm_info("hypervisor extension available\n"); + + switch (kvm_riscv_gstage_mode()) { + case HGATP_MODE_SV32X4: + str = "Sv32x4"; + break; + case HGATP_MODE_SV39X4: + str = "Sv39x4"; + break; + case HGATP_MODE_SV48X4: + str = "Sv48x4"; + break; + case HGATP_MODE_SV57X4: + str = "Sv57x4"; + break; + default: + return -ENODEV; + } + kvm_info("using %s G-stage page table format\n", str); + + kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits()); + + return 0; +} + +void kvm_arch_exit(void) +{ +} + +static int __init riscv_kvm_init(void) +{ + return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); +} +module_init(riscv_kvm_init); diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c new file mode 100644 index 000000000..e47aeb6f0 --- /dev/null +++ b/arch/riscv/kvm/mmu.c @@ -0,0 +1,802 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/hugetlb.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <linux/kvm_host.h> +#include <linux/sched/signal.h> +#include <asm/csr.h> +#include <asm/page.h> +#include <asm/pgtable.h> + +#ifdef CONFIG_64BIT +static unsigned long gstage_mode = (HGATP_MODE_SV39X4 << HGATP_MODE_SHIFT); +static unsigned long gstage_pgd_levels = 3; +#define gstage_index_bits 9 +#else +static unsigned long gstage_mode = (HGATP_MODE_SV32X4 << HGATP_MODE_SHIFT); +static unsigned long gstage_pgd_levels = 2; +#define gstage_index_bits 10 +#endif + +#define gstage_pgd_xbits 2 +#define gstage_pgd_size (1UL << (HGATP_PAGE_SHIFT + gstage_pgd_xbits)) +#define gstage_gpa_bits (HGATP_PAGE_SHIFT + \ + (gstage_pgd_levels * gstage_index_bits) + \ + gstage_pgd_xbits) +#define gstage_gpa_size ((gpa_t)(1ULL << gstage_gpa_bits)) + +#define gstage_pte_leaf(__ptep) \ + (pte_val(*(__ptep)) & (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)) + +static inline unsigned long gstage_pte_index(gpa_t addr, u32 level) +{ + unsigned long mask; + unsigned long shift = HGATP_PAGE_SHIFT + (gstage_index_bits * level); + + if (level == (gstage_pgd_levels - 1)) + mask = (PTRS_PER_PTE * (1UL << gstage_pgd_xbits)) - 1; + else + mask = PTRS_PER_PTE - 1; + + return (addr >> shift) & mask; +} + +static inline unsigned long gstage_pte_page_vaddr(pte_t pte) +{ + return (unsigned long)pfn_to_virt(__page_val_to_pfn(pte_val(pte))); +} + +static int gstage_page_size_to_level(unsigned long page_size, u32 *out_level) +{ + u32 i; + unsigned long psz = 1UL << 12; + + for (i = 0; i < gstage_pgd_levels; i++) { + if (page_size == (psz << (i * gstage_index_bits))) { + *out_level = i; + return 0; + } + } + + return -EINVAL; +} + +static int gstage_level_to_page_order(u32 level, unsigned long *out_pgorder) +{ + if (gstage_pgd_levels < level) + return -EINVAL; + + *out_pgorder = 12 + (level * gstage_index_bits); + return 0; +} + +static int gstage_level_to_page_size(u32 level, unsigned long *out_pgsize) +{ + int rc; + unsigned long page_order = PAGE_SHIFT; + + rc = gstage_level_to_page_order(level, &page_order); + if (rc) + return rc; + + *out_pgsize = BIT(page_order); + return 0; +} + +static bool gstage_get_leaf_entry(struct kvm *kvm, gpa_t addr, + pte_t **ptepp, u32 *ptep_level) +{ + pte_t *ptep; + u32 current_level = gstage_pgd_levels - 1; + + *ptep_level = current_level; + ptep = (pte_t *)kvm->arch.pgd; + ptep = &ptep[gstage_pte_index(addr, current_level)]; + while (ptep && pte_val(*ptep)) { + if (gstage_pte_leaf(ptep)) { + *ptep_level = current_level; + *ptepp = ptep; + return true; + } + + if (current_level) { + current_level--; + *ptep_level = current_level; + ptep = (pte_t *)gstage_pte_page_vaddr(*ptep); + ptep = &ptep[gstage_pte_index(addr, current_level)]; + } else { + ptep = NULL; + } + } + + return false; +} + +static void gstage_remote_tlb_flush(struct kvm *kvm, u32 level, gpa_t addr) +{ + unsigned long order = PAGE_SHIFT; + + if (gstage_level_to_page_order(level, &order)) + return; + addr &= ~(BIT(order) - 1); + + kvm_riscv_hfence_gvma_vmid_gpa(kvm, -1UL, 0, addr, BIT(order), order); +} + +static int gstage_set_pte(struct kvm *kvm, u32 level, + struct kvm_mmu_memory_cache *pcache, + gpa_t addr, const pte_t *new_pte) +{ + u32 current_level = gstage_pgd_levels - 1; + pte_t *next_ptep = (pte_t *)kvm->arch.pgd; + pte_t *ptep = &next_ptep[gstage_pte_index(addr, current_level)]; + + if (current_level < level) + return -EINVAL; + + while (current_level != level) { + if (gstage_pte_leaf(ptep)) + return -EEXIST; + + if (!pte_val(*ptep)) { + if (!pcache) + return -ENOMEM; + next_ptep = kvm_mmu_memory_cache_alloc(pcache); + if (!next_ptep) + return -ENOMEM; + *ptep = pfn_pte(PFN_DOWN(__pa(next_ptep)), + __pgprot(_PAGE_TABLE)); + } else { + if (gstage_pte_leaf(ptep)) + return -EEXIST; + next_ptep = (pte_t *)gstage_pte_page_vaddr(*ptep); + } + + current_level--; + ptep = &next_ptep[gstage_pte_index(addr, current_level)]; + } + + *ptep = *new_pte; + if (gstage_pte_leaf(ptep)) + gstage_remote_tlb_flush(kvm, current_level, addr); + + return 0; +} + +static int gstage_map_page(struct kvm *kvm, + struct kvm_mmu_memory_cache *pcache, + gpa_t gpa, phys_addr_t hpa, + unsigned long page_size, + bool page_rdonly, bool page_exec) +{ + int ret; + u32 level = 0; + pte_t new_pte; + pgprot_t prot; + + ret = gstage_page_size_to_level(page_size, &level); + if (ret) + return ret; + + /* + * A RISC-V implementation can choose to either: + * 1) Update 'A' and 'D' PTE bits in hardware + * 2) Generate page fault when 'A' and/or 'D' bits are not set + * PTE so that software can update these bits. + * + * We support both options mentioned above. To achieve this, we + * always set 'A' and 'D' PTE bits at time of creating G-stage + * mapping. To support KVM dirty page logging with both options + * mentioned above, we will write-protect G-stage PTEs to track + * dirty pages. + */ + + if (page_exec) { + if (page_rdonly) + prot = PAGE_READ_EXEC; + else + prot = PAGE_WRITE_EXEC; + } else { + if (page_rdonly) + prot = PAGE_READ; + else + prot = PAGE_WRITE; + } + new_pte = pfn_pte(PFN_DOWN(hpa), prot); + new_pte = pte_mkdirty(new_pte); + + return gstage_set_pte(kvm, level, pcache, gpa, &new_pte); +} + +enum gstage_op { + GSTAGE_OP_NOP = 0, /* Nothing */ + GSTAGE_OP_CLEAR, /* Clear/Unmap */ + GSTAGE_OP_WP, /* Write-protect */ +}; + +static void gstage_op_pte(struct kvm *kvm, gpa_t addr, + pte_t *ptep, u32 ptep_level, enum gstage_op op) +{ + int i, ret; + pte_t *next_ptep; + u32 next_ptep_level; + unsigned long next_page_size, page_size; + + ret = gstage_level_to_page_size(ptep_level, &page_size); + if (ret) + return; + + BUG_ON(addr & (page_size - 1)); + + if (!pte_val(*ptep)) + return; + + if (ptep_level && !gstage_pte_leaf(ptep)) { + next_ptep = (pte_t *)gstage_pte_page_vaddr(*ptep); + next_ptep_level = ptep_level - 1; + ret = gstage_level_to_page_size(next_ptep_level, + &next_page_size); + if (ret) + return; + + if (op == GSTAGE_OP_CLEAR) + set_pte(ptep, __pte(0)); + for (i = 0; i < PTRS_PER_PTE; i++) + gstage_op_pte(kvm, addr + i * next_page_size, + &next_ptep[i], next_ptep_level, op); + if (op == GSTAGE_OP_CLEAR) + put_page(virt_to_page(next_ptep)); + } else { + if (op == GSTAGE_OP_CLEAR) + set_pte(ptep, __pte(0)); + else if (op == GSTAGE_OP_WP) + set_pte(ptep, __pte(pte_val(*ptep) & ~_PAGE_WRITE)); + gstage_remote_tlb_flush(kvm, ptep_level, addr); + } +} + +static void gstage_unmap_range(struct kvm *kvm, gpa_t start, + gpa_t size, bool may_block) +{ + int ret; + pte_t *ptep; + u32 ptep_level; + bool found_leaf; + unsigned long page_size; + gpa_t addr = start, end = start + size; + + while (addr < end) { + found_leaf = gstage_get_leaf_entry(kvm, addr, + &ptep, &ptep_level); + ret = gstage_level_to_page_size(ptep_level, &page_size); + if (ret) + break; + + if (!found_leaf) + goto next; + + if (!(addr & (page_size - 1)) && ((end - addr) >= page_size)) + gstage_op_pte(kvm, addr, ptep, + ptep_level, GSTAGE_OP_CLEAR); + +next: + addr += page_size; + + /* + * If the range is too large, release the kvm->mmu_lock + * to prevent starvation and lockup detector warnings. + */ + if (may_block && addr < end) + cond_resched_lock(&kvm->mmu_lock); + } +} + +static void gstage_wp_range(struct kvm *kvm, gpa_t start, gpa_t end) +{ + int ret; + pte_t *ptep; + u32 ptep_level; + bool found_leaf; + gpa_t addr = start; + unsigned long page_size; + + while (addr < end) { + found_leaf = gstage_get_leaf_entry(kvm, addr, + &ptep, &ptep_level); + ret = gstage_level_to_page_size(ptep_level, &page_size); + if (ret) + break; + + if (!found_leaf) + goto next; + + if (!(addr & (page_size - 1)) && ((end - addr) >= page_size)) + gstage_op_pte(kvm, addr, ptep, + ptep_level, GSTAGE_OP_WP); + +next: + addr += page_size; + } +} + +static void gstage_wp_memory_region(struct kvm *kvm, int slot) +{ + struct kvm_memslots *slots = kvm_memslots(kvm); + struct kvm_memory_slot *memslot = id_to_memslot(slots, slot); + phys_addr_t start = memslot->base_gfn << PAGE_SHIFT; + phys_addr_t end = (memslot->base_gfn + memslot->npages) << PAGE_SHIFT; + + spin_lock(&kvm->mmu_lock); + gstage_wp_range(kvm, start, end); + spin_unlock(&kvm->mmu_lock); + kvm_flush_remote_tlbs(kvm); +} + +int kvm_riscv_gstage_ioremap(struct kvm *kvm, gpa_t gpa, + phys_addr_t hpa, unsigned long size, + bool writable, bool in_atomic) +{ + pte_t pte; + int ret = 0; + unsigned long pfn; + phys_addr_t addr, end; + struct kvm_mmu_memory_cache pcache = { + .gfp_custom = (in_atomic) ? GFP_ATOMIC | __GFP_ACCOUNT : 0, + .gfp_zero = __GFP_ZERO, + }; + + end = (gpa + size + PAGE_SIZE - 1) & PAGE_MASK; + pfn = __phys_to_pfn(hpa); + + for (addr = gpa; addr < end; addr += PAGE_SIZE) { + pte = pfn_pte(pfn, PAGE_KERNEL_IO); + + if (!writable) + pte = pte_wrprotect(pte); + + ret = kvm_mmu_topup_memory_cache(&pcache, gstage_pgd_levels); + if (ret) + goto out; + + spin_lock(&kvm->mmu_lock); + ret = gstage_set_pte(kvm, 0, &pcache, addr, &pte); + spin_unlock(&kvm->mmu_lock); + if (ret) + goto out; + + pfn++; + } + +out: + kvm_mmu_free_memory_cache(&pcache); + return ret; +} + +void kvm_riscv_gstage_iounmap(struct kvm *kvm, gpa_t gpa, unsigned long size) +{ + spin_lock(&kvm->mmu_lock); + gstage_unmap_range(kvm, gpa, size, false); + spin_unlock(&kvm->mmu_lock); +} + +void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, + struct kvm_memory_slot *slot, + gfn_t gfn_offset, + unsigned long mask) +{ + phys_addr_t base_gfn = slot->base_gfn + gfn_offset; + phys_addr_t start = (base_gfn + __ffs(mask)) << PAGE_SHIFT; + phys_addr_t end = (base_gfn + __fls(mask) + 1) << PAGE_SHIFT; + + gstage_wp_range(kvm, start, end); +} + +void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) +{ +} + +void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, + const struct kvm_memory_slot *memslot) +{ + kvm_flush_remote_tlbs(kvm); +} + +void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free) +{ +} + +void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) +{ +} + +void kvm_arch_flush_shadow_all(struct kvm *kvm) +{ + kvm_riscv_gstage_free_pgd(kvm); +} + +void kvm_arch_flush_shadow_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot) +{ + gpa_t gpa = slot->base_gfn << PAGE_SHIFT; + phys_addr_t size = slot->npages << PAGE_SHIFT; + + spin_lock(&kvm->mmu_lock); + gstage_unmap_range(kvm, gpa, size, false); + spin_unlock(&kvm->mmu_lock); +} + +void kvm_arch_commit_memory_region(struct kvm *kvm, + struct kvm_memory_slot *old, + const struct kvm_memory_slot *new, + enum kvm_mr_change change) +{ + /* + * At this point memslot has been committed and there is an + * allocated dirty_bitmap[], dirty pages will be tracked while + * the memory slot is write protected. + */ + if (change != KVM_MR_DELETE && new->flags & KVM_MEM_LOG_DIRTY_PAGES) + gstage_wp_memory_region(kvm, new->id); +} + +int kvm_arch_prepare_memory_region(struct kvm *kvm, + const struct kvm_memory_slot *old, + struct kvm_memory_slot *new, + enum kvm_mr_change change) +{ + hva_t hva, reg_end, size; + gpa_t base_gpa; + bool writable; + int ret = 0; + + if (change != KVM_MR_CREATE && change != KVM_MR_MOVE && + change != KVM_MR_FLAGS_ONLY) + return 0; + + /* + * Prevent userspace from creating a memory region outside of the GPA + * space addressable by the KVM guest GPA space. + */ + if ((new->base_gfn + new->npages) >= + (gstage_gpa_size >> PAGE_SHIFT)) + return -EFAULT; + + hva = new->userspace_addr; + size = new->npages << PAGE_SHIFT; + reg_end = hva + size; + base_gpa = new->base_gfn << PAGE_SHIFT; + writable = !(new->flags & KVM_MEM_READONLY); + + mmap_read_lock(current->mm); + + /* + * A memory region could potentially cover multiple VMAs, and + * any holes between them, so iterate over all of them to find + * out if we can map any of them right now. + * + * +--------------------------------------------+ + * +---------------+----------------+ +----------------+ + * | : VMA 1 | VMA 2 | | VMA 3 : | + * +---------------+----------------+ +----------------+ + * | memory region | + * +--------------------------------------------+ + */ + do { + struct vm_area_struct *vma = find_vma(current->mm, hva); + hva_t vm_start, vm_end; + + if (!vma || vma->vm_start >= reg_end) + break; + + /* + * Mapping a read-only VMA is only allowed if the + * memory region is configured as read-only. + */ + if (writable && !(vma->vm_flags & VM_WRITE)) { + ret = -EPERM; + break; + } + + /* Take the intersection of this VMA with the memory region */ + vm_start = max(hva, vma->vm_start); + vm_end = min(reg_end, vma->vm_end); + + if (vma->vm_flags & VM_PFNMAP) { + gpa_t gpa = base_gpa + (vm_start - hva); + phys_addr_t pa; + + pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; + pa += vm_start - vma->vm_start; + + /* IO region dirty page logging not allowed */ + if (new->flags & KVM_MEM_LOG_DIRTY_PAGES) { + ret = -EINVAL; + goto out; + } + + ret = kvm_riscv_gstage_ioremap(kvm, gpa, pa, + vm_end - vm_start, + writable, false); + if (ret) + break; + } + hva = vm_end; + } while (hva < reg_end); + + if (change == KVM_MR_FLAGS_ONLY) + goto out; + + spin_lock(&kvm->mmu_lock); + if (ret) + gstage_unmap_range(kvm, base_gpa, size, false); + spin_unlock(&kvm->mmu_lock); + +out: + mmap_read_unlock(current->mm); + return ret; +} + +bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range) +{ + if (!kvm->arch.pgd) + return false; + + gstage_unmap_range(kvm, range->start << PAGE_SHIFT, + (range->end - range->start) << PAGE_SHIFT, + range->may_block); + return false; +} + +bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) +{ + int ret; + kvm_pfn_t pfn = pte_pfn(range->pte); + + if (!kvm->arch.pgd) + return false; + + WARN_ON(range->end - range->start != 1); + + ret = gstage_map_page(kvm, NULL, range->start << PAGE_SHIFT, + __pfn_to_phys(pfn), PAGE_SIZE, true, true); + if (ret) { + kvm_debug("Failed to map G-stage page (error %d)\n", ret); + return true; + } + + return false; +} + +bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) +{ + pte_t *ptep; + u32 ptep_level = 0; + u64 size = (range->end - range->start) << PAGE_SHIFT; + + if (!kvm->arch.pgd) + return false; + + WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PGDIR_SIZE); + + if (!gstage_get_leaf_entry(kvm, range->start << PAGE_SHIFT, + &ptep, &ptep_level)) + return false; + + return ptep_test_and_clear_young(NULL, 0, ptep); +} + +bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) +{ + pte_t *ptep; + u32 ptep_level = 0; + u64 size = (range->end - range->start) << PAGE_SHIFT; + + if (!kvm->arch.pgd) + return false; + + WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PGDIR_SIZE); + + if (!gstage_get_leaf_entry(kvm, range->start << PAGE_SHIFT, + &ptep, &ptep_level)) + return false; + + return pte_young(*ptep); +} + +int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, + struct kvm_memory_slot *memslot, + gpa_t gpa, unsigned long hva, bool is_write) +{ + int ret; + kvm_pfn_t hfn; + bool writable; + short vma_pageshift; + gfn_t gfn = gpa >> PAGE_SHIFT; + struct vm_area_struct *vma; + struct kvm *kvm = vcpu->kvm; + struct kvm_mmu_memory_cache *pcache = &vcpu->arch.mmu_page_cache; + bool logging = (memslot->dirty_bitmap && + !(memslot->flags & KVM_MEM_READONLY)) ? true : false; + unsigned long vma_pagesize, mmu_seq; + + /* We need minimum second+third level pages */ + ret = kvm_mmu_topup_memory_cache(pcache, gstage_pgd_levels); + if (ret) { + kvm_err("Failed to topup G-stage cache\n"); + return ret; + } + + mmap_read_lock(current->mm); + + vma = find_vma_intersection(current->mm, hva, hva + 1); + if (unlikely(!vma)) { + kvm_err("Failed to find VMA for hva 0x%lx\n", hva); + mmap_read_unlock(current->mm); + return -EFAULT; + } + + if (is_vm_hugetlb_page(vma)) + vma_pageshift = huge_page_shift(hstate_vma(vma)); + else + vma_pageshift = PAGE_SHIFT; + vma_pagesize = 1ULL << vma_pageshift; + if (logging || (vma->vm_flags & VM_PFNMAP)) + vma_pagesize = PAGE_SIZE; + + if (vma_pagesize == PMD_SIZE || vma_pagesize == PGDIR_SIZE) + gfn = (gpa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; + + /* + * Read mmu_invalidate_seq so that KVM can detect if the results of + * vma_lookup() or gfn_to_pfn_prot() become stale priort to acquiring + * kvm->mmu_lock. + * + * Rely on mmap_read_unlock() for an implicit smp_rmb(), which pairs + * with the smp_wmb() in kvm_mmu_invalidate_end(). + */ + mmu_seq = kvm->mmu_invalidate_seq; + mmap_read_unlock(current->mm); + + if (vma_pagesize != PGDIR_SIZE && + vma_pagesize != PMD_SIZE && + vma_pagesize != PAGE_SIZE) { + kvm_err("Invalid VMA page size 0x%lx\n", vma_pagesize); + return -EFAULT; + } + + hfn = gfn_to_pfn_prot(kvm, gfn, is_write, &writable); + if (hfn == KVM_PFN_ERR_HWPOISON) { + send_sig_mceerr(BUS_MCEERR_AR, (void __user *)hva, + vma_pageshift, current); + return 0; + } + if (is_error_noslot_pfn(hfn)) + return -EFAULT; + + /* + * If logging is active then we allow writable pages only + * for write faults. + */ + if (logging && !is_write) + writable = false; + + spin_lock(&kvm->mmu_lock); + + if (mmu_invalidate_retry(kvm, mmu_seq)) + goto out_unlock; + + if (writable) { + kvm_set_pfn_dirty(hfn); + mark_page_dirty(kvm, gfn); + ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, + vma_pagesize, false, true); + } else { + ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, + vma_pagesize, true, true); + } + + if (ret) + kvm_err("Failed to map in G-stage\n"); + +out_unlock: + spin_unlock(&kvm->mmu_lock); + kvm_set_pfn_accessed(hfn); + kvm_release_pfn_clean(hfn); + return ret; +} + +int kvm_riscv_gstage_alloc_pgd(struct kvm *kvm) +{ + struct page *pgd_page; + + if (kvm->arch.pgd != NULL) { + kvm_err("kvm_arch already initialized?\n"); + return -EINVAL; + } + + pgd_page = alloc_pages(GFP_KERNEL | __GFP_ZERO, + get_order(gstage_pgd_size)); + if (!pgd_page) + return -ENOMEM; + kvm->arch.pgd = page_to_virt(pgd_page); + kvm->arch.pgd_phys = page_to_phys(pgd_page); + + return 0; +} + +void kvm_riscv_gstage_free_pgd(struct kvm *kvm) +{ + void *pgd = NULL; + + spin_lock(&kvm->mmu_lock); + if (kvm->arch.pgd) { + gstage_unmap_range(kvm, 0UL, gstage_gpa_size, false); + pgd = READ_ONCE(kvm->arch.pgd); + kvm->arch.pgd = NULL; + kvm->arch.pgd_phys = 0; + } + spin_unlock(&kvm->mmu_lock); + + if (pgd) + free_pages((unsigned long)pgd, get_order(gstage_pgd_size)); +} + +void kvm_riscv_gstage_update_hgatp(struct kvm_vcpu *vcpu) +{ + unsigned long hgatp = gstage_mode; + struct kvm_arch *k = &vcpu->kvm->arch; + + hgatp |= (READ_ONCE(k->vmid.vmid) << HGATP_VMID_SHIFT) & + HGATP_VMID_MASK; + hgatp |= (k->pgd_phys >> PAGE_SHIFT) & HGATP_PPN; + + csr_write(CSR_HGATP, hgatp); + + if (!kvm_riscv_gstage_vmid_bits()) + kvm_riscv_local_hfence_gvma_all(); +} + +void kvm_riscv_gstage_mode_detect(void) +{ +#ifdef CONFIG_64BIT + /* Try Sv57x4 G-stage mode */ + csr_write(CSR_HGATP, HGATP_MODE_SV57X4 << HGATP_MODE_SHIFT); + if ((csr_read(CSR_HGATP) >> HGATP_MODE_SHIFT) == HGATP_MODE_SV57X4) { + gstage_mode = (HGATP_MODE_SV57X4 << HGATP_MODE_SHIFT); + gstage_pgd_levels = 5; + goto skip_sv48x4_test; + } + + /* Try Sv48x4 G-stage mode */ + csr_write(CSR_HGATP, HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); + if ((csr_read(CSR_HGATP) >> HGATP_MODE_SHIFT) == HGATP_MODE_SV48X4) { + gstage_mode = (HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); + gstage_pgd_levels = 4; + } +skip_sv48x4_test: + + csr_write(CSR_HGATP, 0); + kvm_riscv_local_hfence_gvma_all(); +#endif +} + +unsigned long kvm_riscv_gstage_mode(void) +{ + return gstage_mode >> HGATP_MODE_SHIFT; +} + +int kvm_riscv_gstage_gpa_bits(void) +{ + return gstage_gpa_bits; +} diff --git a/arch/riscv/kvm/tlb.c b/arch/riscv/kvm/tlb.c new file mode 100644 index 000000000..309d79b3e --- /dev/null +++ b/arch/riscv/kvm/tlb.c @@ -0,0 +1,402 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022 Ventana Micro Systems Inc. + */ + +#include <linux/bitmap.h> +#include <linux/cpumask.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/smp.h> +#include <linux/kvm_host.h> +#include <asm/cacheflush.h> +#include <asm/csr.h> +#include <asm/hwcap.h> +#include <asm/insn-def.h> + +#define has_svinval() \ + static_branch_unlikely(&riscv_isa_ext_keys[RISCV_ISA_EXT_KEY_SVINVAL]) + +void kvm_riscv_local_hfence_gvma_vmid_gpa(unsigned long vmid, + gpa_t gpa, gpa_t gpsz, + unsigned long order) +{ + gpa_t pos; + + if (PTRS_PER_PTE < (gpsz >> order)) { + kvm_riscv_local_hfence_gvma_vmid_all(vmid); + return; + } + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile (HINVAL_GVMA(%0, %1) + : : "r" (pos >> 2), "r" (vmid) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile (HFENCE_GVMA(%0, %1) + : : "r" (pos >> 2), "r" (vmid) : "memory"); + } +} + +void kvm_riscv_local_hfence_gvma_vmid_all(unsigned long vmid) +{ + asm volatile(HFENCE_GVMA(zero, %0) : : "r" (vmid) : "memory"); +} + +void kvm_riscv_local_hfence_gvma_gpa(gpa_t gpa, gpa_t gpsz, + unsigned long order) +{ + gpa_t pos; + + if (PTRS_PER_PTE < (gpsz >> order)) { + kvm_riscv_local_hfence_gvma_all(); + return; + } + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile(HINVAL_GVMA(%0, zero) + : : "r" (pos >> 2) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile(HFENCE_GVMA(%0, zero) + : : "r" (pos >> 2) : "memory"); + } +} + +void kvm_riscv_local_hfence_gvma_all(void) +{ + asm volatile(HFENCE_GVMA(zero, zero) : : : "memory"); +} + +void kvm_riscv_local_hfence_vvma_asid_gva(unsigned long vmid, + unsigned long asid, + unsigned long gva, + unsigned long gvsz, + unsigned long order) +{ + unsigned long pos, hgatp; + + if (PTRS_PER_PTE < (gvsz >> order)) { + kvm_riscv_local_hfence_vvma_asid_all(vmid, asid); + return; + } + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HINVAL_VVMA(%0, %1) + : : "r" (pos), "r" (asid) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HFENCE_VVMA(%0, %1) + : : "r" (pos), "r" (asid) : "memory"); + } + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_hfence_vvma_asid_all(unsigned long vmid, + unsigned long asid) +{ + unsigned long hgatp; + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + asm volatile(HFENCE_VVMA(zero, %0) : : "r" (asid) : "memory"); + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_hfence_vvma_gva(unsigned long vmid, + unsigned long gva, unsigned long gvsz, + unsigned long order) +{ + unsigned long pos, hgatp; + + if (PTRS_PER_PTE < (gvsz >> order)) { + kvm_riscv_local_hfence_vvma_all(vmid); + return; + } + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HINVAL_VVMA(%0, zero) + : : "r" (pos) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HFENCE_VVMA(%0, zero) + : : "r" (pos) : "memory"); + } + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_hfence_vvma_all(unsigned long vmid) +{ + unsigned long hgatp; + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + asm volatile(HFENCE_VVMA(zero, zero) : : : "memory"); + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_tlb_sanitize(struct kvm_vcpu *vcpu) +{ + unsigned long vmid; + + if (!kvm_riscv_gstage_vmid_bits() || + vcpu->arch.last_exit_cpu == vcpu->cpu) + return; + + /* + * On RISC-V platforms with hardware VMID support, we share same + * VMID for all VCPUs of a particular Guest/VM. This means we might + * have stale G-stage TLB entries on the current Host CPU due to + * some other VCPU of the same Guest which ran previously on the + * current Host CPU. + * + * To cleanup stale TLB entries, we simply flush all G-stage TLB + * entries by VMID whenever underlying Host CPU changes for a VCPU. + */ + + vmid = READ_ONCE(vcpu->kvm->arch.vmid.vmid); + kvm_riscv_local_hfence_gvma_vmid_all(vmid); +} + +void kvm_riscv_fence_i_process(struct kvm_vcpu *vcpu) +{ + local_flush_icache_all(); +} + +void kvm_riscv_hfence_gvma_vmid_all_process(struct kvm_vcpu *vcpu) +{ + struct kvm_vmid *vmid; + + vmid = &vcpu->kvm->arch.vmid; + kvm_riscv_local_hfence_gvma_vmid_all(READ_ONCE(vmid->vmid)); +} + +void kvm_riscv_hfence_vvma_all_process(struct kvm_vcpu *vcpu) +{ + struct kvm_vmid *vmid; + + vmid = &vcpu->kvm->arch.vmid; + kvm_riscv_local_hfence_vvma_all(READ_ONCE(vmid->vmid)); +} + +static bool vcpu_hfence_dequeue(struct kvm_vcpu *vcpu, + struct kvm_riscv_hfence *out_data) +{ + bool ret = false; + struct kvm_vcpu_arch *varch = &vcpu->arch; + + spin_lock(&varch->hfence_lock); + + if (varch->hfence_queue[varch->hfence_head].type) { + memcpy(out_data, &varch->hfence_queue[varch->hfence_head], + sizeof(*out_data)); + varch->hfence_queue[varch->hfence_head].type = 0; + + varch->hfence_head++; + if (varch->hfence_head == KVM_RISCV_VCPU_MAX_HFENCE) + varch->hfence_head = 0; + + ret = true; + } + + spin_unlock(&varch->hfence_lock); + + return ret; +} + +static bool vcpu_hfence_enqueue(struct kvm_vcpu *vcpu, + const struct kvm_riscv_hfence *data) +{ + bool ret = false; + struct kvm_vcpu_arch *varch = &vcpu->arch; + + spin_lock(&varch->hfence_lock); + + if (!varch->hfence_queue[varch->hfence_tail].type) { + memcpy(&varch->hfence_queue[varch->hfence_tail], + data, sizeof(*data)); + + varch->hfence_tail++; + if (varch->hfence_tail == KVM_RISCV_VCPU_MAX_HFENCE) + varch->hfence_tail = 0; + + ret = true; + } + + spin_unlock(&varch->hfence_lock); + + return ret; +} + +void kvm_riscv_hfence_process(struct kvm_vcpu *vcpu) +{ + struct kvm_riscv_hfence d = { 0 }; + struct kvm_vmid *v = &vcpu->kvm->arch.vmid; + + while (vcpu_hfence_dequeue(vcpu, &d)) { + switch (d.type) { + case KVM_RISCV_HFENCE_UNKNOWN: + break; + case KVM_RISCV_HFENCE_GVMA_VMID_GPA: + kvm_riscv_local_hfence_gvma_vmid_gpa( + READ_ONCE(v->vmid), + d.addr, d.size, d.order); + break; + case KVM_RISCV_HFENCE_VVMA_ASID_GVA: + kvm_riscv_local_hfence_vvma_asid_gva( + READ_ONCE(v->vmid), d.asid, + d.addr, d.size, d.order); + break; + case KVM_RISCV_HFENCE_VVMA_ASID_ALL: + kvm_riscv_local_hfence_vvma_asid_all( + READ_ONCE(v->vmid), d.asid); + break; + case KVM_RISCV_HFENCE_VVMA_GVA: + kvm_riscv_local_hfence_vvma_gva( + READ_ONCE(v->vmid), + d.addr, d.size, d.order); + break; + default: + break; + } + } +} + +static void make_xfence_request(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned int req, unsigned int fallback_req, + const struct kvm_riscv_hfence *data) +{ + unsigned long i; + struct kvm_vcpu *vcpu; + unsigned int actual_req = req; + DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS); + + bitmap_clear(vcpu_mask, 0, KVM_MAX_VCPUS); + kvm_for_each_vcpu(i, vcpu, kvm) { + if (hbase != -1UL) { + if (vcpu->vcpu_id < hbase) + continue; + if (!(hmask & (1UL << (vcpu->vcpu_id - hbase)))) + continue; + } + + bitmap_set(vcpu_mask, i, 1); + + if (!data || !data->type) + continue; + + /* + * Enqueue hfence data to VCPU hfence queue. If we don't + * have space in the VCPU hfence queue then fallback to + * a more conservative hfence request. + */ + if (!vcpu_hfence_enqueue(vcpu, data)) + actual_req = fallback_req; + } + + kvm_make_vcpus_request_mask(kvm, actual_req, vcpu_mask); +} + +void kvm_riscv_fence_i(struct kvm *kvm, + unsigned long hbase, unsigned long hmask) +{ + make_xfence_request(kvm, hbase, hmask, KVM_REQ_FENCE_I, + KVM_REQ_FENCE_I, NULL); +} + +void kvm_riscv_hfence_gvma_vmid_gpa(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + gpa_t gpa, gpa_t gpsz, + unsigned long order) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_GVMA_VMID_GPA; + data.asid = 0; + data.addr = gpa; + data.size = gpsz; + data.order = order; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_GVMA_VMID_ALL, &data); +} + +void kvm_riscv_hfence_gvma_vmid_all(struct kvm *kvm, + unsigned long hbase, unsigned long hmask) +{ + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_GVMA_VMID_ALL, + KVM_REQ_HFENCE_GVMA_VMID_ALL, NULL); +} + +void kvm_riscv_hfence_vvma_asid_gva(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned long gva, unsigned long gvsz, + unsigned long order, unsigned long asid) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_VVMA_ASID_GVA; + data.asid = asid; + data.addr = gva; + data.size = gvsz; + data.order = order; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_VVMA_ALL, &data); +} + +void kvm_riscv_hfence_vvma_asid_all(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned long asid) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_VVMA_ASID_ALL; + data.asid = asid; + data.addr = data.size = data.order = 0; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_VVMA_ALL, &data); +} + +void kvm_riscv_hfence_vvma_gva(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned long gva, unsigned long gvsz, + unsigned long order) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_VVMA_GVA; + data.asid = 0; + data.addr = gva; + data.size = gvsz; + data.order = order; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_VVMA_ALL, &data); +} + +void kvm_riscv_hfence_vvma_all(struct kvm *kvm, + unsigned long hbase, unsigned long hmask) +{ + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_VVMA_ALL, + KVM_REQ_HFENCE_VVMA_ALL, NULL); +} diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c new file mode 100644 index 000000000..5174ef54a --- /dev/null +++ b/arch/riscv/kvm/vcpu.c @@ -0,0 +1,1091 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/bitops.h> +#include <linux/entry-kvm.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kdebug.h> +#include <linux/module.h> +#include <linux/percpu.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <linux/sched/signal.h> +#include <linux/fs.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/cacheflush.h> +#include <asm/hwcap.h> + +const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = { + KVM_GENERIC_VCPU_STATS(), + STATS_DESC_COUNTER(VCPU, ecall_exit_stat), + STATS_DESC_COUNTER(VCPU, wfi_exit_stat), + STATS_DESC_COUNTER(VCPU, mmio_exit_user), + STATS_DESC_COUNTER(VCPU, mmio_exit_kernel), + STATS_DESC_COUNTER(VCPU, csr_exit_user), + STATS_DESC_COUNTER(VCPU, csr_exit_kernel), + STATS_DESC_COUNTER(VCPU, signal_exits), + STATS_DESC_COUNTER(VCPU, exits) +}; + +const struct kvm_stats_header kvm_vcpu_stats_header = { + .name_size = KVM_STATS_NAME_SIZE, + .num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc), + .id_offset = sizeof(struct kvm_stats_header), + .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE, + .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE + + sizeof(kvm_vcpu_stats_desc), +}; + +#define KVM_RISCV_BASE_ISA_MASK GENMASK(25, 0) + +#define KVM_ISA_EXT_ARR(ext) [KVM_RISCV_ISA_EXT_##ext] = RISCV_ISA_EXT_##ext + +/* Mapping between KVM ISA Extension ID & Host ISA extension ID */ +static const unsigned long kvm_isa_ext_arr[] = { + [KVM_RISCV_ISA_EXT_A] = RISCV_ISA_EXT_a, + [KVM_RISCV_ISA_EXT_C] = RISCV_ISA_EXT_c, + [KVM_RISCV_ISA_EXT_D] = RISCV_ISA_EXT_d, + [KVM_RISCV_ISA_EXT_F] = RISCV_ISA_EXT_f, + [KVM_RISCV_ISA_EXT_H] = RISCV_ISA_EXT_h, + [KVM_RISCV_ISA_EXT_I] = RISCV_ISA_EXT_i, + [KVM_RISCV_ISA_EXT_M] = RISCV_ISA_EXT_m, + + KVM_ISA_EXT_ARR(SSTC), + KVM_ISA_EXT_ARR(SVINVAL), + KVM_ISA_EXT_ARR(SVPBMT), + KVM_ISA_EXT_ARR(ZIHINTPAUSE), + KVM_ISA_EXT_ARR(ZICBOM), +}; + +static unsigned long kvm_riscv_vcpu_base2isa_ext(unsigned long base_ext) +{ + unsigned long i; + + for (i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++) { + if (kvm_isa_ext_arr[i] == base_ext) + return i; + } + + return KVM_RISCV_ISA_EXT_MAX; +} + +static bool kvm_riscv_vcpu_isa_enable_allowed(unsigned long ext) +{ + switch (ext) { + case KVM_RISCV_ISA_EXT_H: + return false; + default: + break; + } + + return true; +} + +static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext) +{ + switch (ext) { + case KVM_RISCV_ISA_EXT_A: + case KVM_RISCV_ISA_EXT_C: + case KVM_RISCV_ISA_EXT_I: + case KVM_RISCV_ISA_EXT_M: + case KVM_RISCV_ISA_EXT_SSTC: + case KVM_RISCV_ISA_EXT_SVINVAL: + case KVM_RISCV_ISA_EXT_ZIHINTPAUSE: + return false; + default: + break; + } + + return true; +} + +static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr; + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + struct kvm_cpu_context *reset_cntx = &vcpu->arch.guest_reset_context; + bool loaded; + + /** + * The preemption should be disabled here because it races with + * kvm_sched_out/kvm_sched_in(called from preempt notifiers) which + * also calls vcpu_load/put. + */ + get_cpu(); + loaded = (vcpu->cpu != -1); + if (loaded) + kvm_arch_vcpu_put(vcpu); + + vcpu->arch.last_exit_cpu = -1; + + memcpy(csr, reset_csr, sizeof(*csr)); + + memcpy(cntx, reset_cntx, sizeof(*cntx)); + + kvm_riscv_vcpu_fp_reset(vcpu); + + kvm_riscv_vcpu_timer_reset(vcpu); + + WRITE_ONCE(vcpu->arch.irqs_pending, 0); + WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0); + + vcpu->arch.hfence_head = 0; + vcpu->arch.hfence_tail = 0; + memset(vcpu->arch.hfence_queue, 0, sizeof(vcpu->arch.hfence_queue)); + + /* Reset the guest CSRs for hotplug usecase */ + if (loaded) + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + put_cpu(); +} + +int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) +{ + return 0; +} + +int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *cntx; + struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr; + unsigned long host_isa, i; + + /* Mark this VCPU never ran */ + vcpu->arch.ran_atleast_once = false; + vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; + bitmap_zero(vcpu->arch.isa, RISCV_ISA_EXT_MAX); + + /* Setup ISA features available to VCPU */ + for (i = 0; i < ARRAY_SIZE(kvm_isa_ext_arr); i++) { + host_isa = kvm_isa_ext_arr[i]; + if (__riscv_isa_extension_available(NULL, host_isa) && + kvm_riscv_vcpu_isa_enable_allowed(i)) + set_bit(host_isa, vcpu->arch.isa); + } + + /* Setup VCPU hfence queue */ + spin_lock_init(&vcpu->arch.hfence_lock); + + /* Setup reset state of shadow SSTATUS and HSTATUS CSRs */ + cntx = &vcpu->arch.guest_reset_context; + cntx->sstatus = SR_SPP | SR_SPIE; + cntx->hstatus = 0; + cntx->hstatus |= HSTATUS_VTW; + cntx->hstatus |= HSTATUS_SPVP; + cntx->hstatus |= HSTATUS_SPV; + + /* By default, make CY, TM, and IR counters accessible in VU mode */ + reset_csr->scounteren = 0x7; + + /* Setup VCPU timer */ + kvm_riscv_vcpu_timer_init(vcpu); + + /* Reset VCPU */ + kvm_riscv_reset_vcpu(vcpu); + + return 0; +} + +void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) +{ + /** + * vcpu with id 0 is the designated boot cpu. + * Keep all vcpus with non-zero id in power-off state so that + * they can be brought up using SBI HSM extension. + */ + if (vcpu->vcpu_idx != 0) + kvm_riscv_vcpu_power_off(vcpu); +} + +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) +{ + /* Cleanup VCPU timer */ + kvm_riscv_vcpu_timer_deinit(vcpu); + + /* Free unused pages pre-allocated for G-stage page table mappings */ + kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); +} + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) +{ + return kvm_riscv_vcpu_timer_pending(vcpu); +} + +void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) +{ +} + +void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) +{ +} + +int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu) +{ + return (kvm_riscv_vcpu_has_interrupts(vcpu, -1UL) && + !vcpu->arch.power_off && !vcpu->arch.pause); +} + +int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) +{ + return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; +} + +bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) +{ + return (vcpu->arch.guest_context.sstatus & SR_SPP) ? true : false; +} + +vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + +static int kvm_riscv_vcpu_get_reg_config(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_CONFIG); + unsigned long reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + + switch (reg_num) { + case KVM_REG_RISCV_CONFIG_REG(isa): + reg_val = vcpu->arch.isa[0] & KVM_RISCV_BASE_ISA_MASK; + break; + case KVM_REG_RISCV_CONFIG_REG(zicbom_block_size): + if (!riscv_isa_extension_available(vcpu->arch.isa, ZICBOM)) + return -EINVAL; + reg_val = riscv_cbom_block_size; + break; + default: + return -EINVAL; + } + + if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +static int kvm_riscv_vcpu_set_reg_config(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_CONFIG); + unsigned long i, isa_ext, reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + switch (reg_num) { + case KVM_REG_RISCV_CONFIG_REG(isa): + /* + * This ONE REG interface is only defined for + * single letter extensions. + */ + if (fls(reg_val) >= RISCV_ISA_EXT_BASE) + return -EINVAL; + + if (!vcpu->arch.ran_atleast_once) { + /* Ignore the enable/disable request for certain extensions */ + for (i = 0; i < RISCV_ISA_EXT_BASE; i++) { + isa_ext = kvm_riscv_vcpu_base2isa_ext(i); + if (isa_ext >= KVM_RISCV_ISA_EXT_MAX) { + reg_val &= ~BIT(i); + continue; + } + if (!kvm_riscv_vcpu_isa_enable_allowed(isa_ext)) + if (reg_val & BIT(i)) + reg_val &= ~BIT(i); + if (!kvm_riscv_vcpu_isa_disable_allowed(isa_ext)) + if (!(reg_val & BIT(i))) + reg_val |= BIT(i); + } + reg_val &= riscv_isa_extension_base(NULL); + /* Do not modify anything beyond single letter extensions */ + reg_val = (vcpu->arch.isa[0] & ~KVM_RISCV_BASE_ISA_MASK) | + (reg_val & KVM_RISCV_BASE_ISA_MASK); + vcpu->arch.isa[0] = reg_val; + kvm_riscv_vcpu_fp_reset(vcpu); + } else { + return -EOPNOTSUPP; + } + break; + case KVM_REG_RISCV_CONFIG_REG(zicbom_block_size): + return -EOPNOTSUPP; + default: + return -EINVAL; + } + + return 0; +} + +static int kvm_riscv_vcpu_get_reg_core(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_CORE); + unsigned long reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long)) + return -EINVAL; + + if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc)) + reg_val = cntx->sepc; + else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num && + reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6)) + reg_val = ((unsigned long *)cntx)[reg_num]; + else if (reg_num == KVM_REG_RISCV_CORE_REG(mode)) + reg_val = (cntx->sstatus & SR_SPP) ? + KVM_RISCV_MODE_S : KVM_RISCV_MODE_U; + else + return -EINVAL; + + if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +static int kvm_riscv_vcpu_set_reg_core(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_CORE); + unsigned long reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long)) + return -EINVAL; + + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc)) + cntx->sepc = reg_val; + else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num && + reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6)) + ((unsigned long *)cntx)[reg_num] = reg_val; + else if (reg_num == KVM_REG_RISCV_CORE_REG(mode)) { + if (reg_val == KVM_RISCV_MODE_S) + cntx->sstatus |= SR_SPP; + else + cntx->sstatus &= ~SR_SPP; + } else + return -EINVAL; + + return 0; +} + +static int kvm_riscv_vcpu_get_reg_csr(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_CSR); + unsigned long reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long)) + return -EINVAL; + + if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) { + kvm_riscv_vcpu_flush_interrupts(vcpu); + reg_val = (csr->hvip >> VSIP_TO_HVIP_SHIFT) & VSIP_VALID_MASK; + } else + reg_val = ((unsigned long *)csr)[reg_num]; + + if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +static int kvm_riscv_vcpu_set_reg_csr(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_CSR); + unsigned long reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long)) + return -EINVAL; + + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) { + reg_val &= VSIP_VALID_MASK; + reg_val <<= VSIP_TO_HVIP_SHIFT; + } + + ((unsigned long *)csr)[reg_num] = reg_val; + + if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) + WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0); + + return 0; +} + +static int kvm_riscv_vcpu_get_reg_isa_ext(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_ISA_EXT); + unsigned long reg_val = 0; + unsigned long host_isa_ext; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + + if (reg_num >= KVM_RISCV_ISA_EXT_MAX || + reg_num >= ARRAY_SIZE(kvm_isa_ext_arr)) + return -EINVAL; + + host_isa_ext = kvm_isa_ext_arr[reg_num]; + if (__riscv_isa_extension_available(vcpu->arch.isa, host_isa_ext)) + reg_val = 1; /* Mark the given extension as available */ + + if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +static int kvm_riscv_vcpu_set_reg_isa_ext(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_ISA_EXT); + unsigned long reg_val; + unsigned long host_isa_ext; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + + if (reg_num >= KVM_RISCV_ISA_EXT_MAX || + reg_num >= ARRAY_SIZE(kvm_isa_ext_arr)) + return -EINVAL; + + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + host_isa_ext = kvm_isa_ext_arr[reg_num]; + if (!__riscv_isa_extension_available(NULL, host_isa_ext)) + return -EOPNOTSUPP; + + if (!vcpu->arch.ran_atleast_once) { + /* + * All multi-letter extension and a few single letter + * extension can be disabled + */ + if (reg_val == 1 && + kvm_riscv_vcpu_isa_enable_allowed(reg_num)) + set_bit(host_isa_ext, vcpu->arch.isa); + else if (!reg_val && + kvm_riscv_vcpu_isa_disable_allowed(reg_num)) + clear_bit(host_isa_ext, vcpu->arch.isa); + else + return -EINVAL; + kvm_riscv_vcpu_fp_reset(vcpu); + } else { + return -EOPNOTSUPP; + } + + return 0; +} + +static int kvm_riscv_vcpu_set_reg(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CONFIG) + return kvm_riscv_vcpu_set_reg_config(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CORE) + return kvm_riscv_vcpu_set_reg_core(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CSR) + return kvm_riscv_vcpu_set_reg_csr(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_TIMER) + return kvm_riscv_vcpu_set_reg_timer(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_F) + return kvm_riscv_vcpu_set_reg_fp(vcpu, reg, + KVM_REG_RISCV_FP_F); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_D) + return kvm_riscv_vcpu_set_reg_fp(vcpu, reg, + KVM_REG_RISCV_FP_D); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_ISA_EXT) + return kvm_riscv_vcpu_set_reg_isa_ext(vcpu, reg); + + return -EINVAL; +} + +static int kvm_riscv_vcpu_get_reg(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CONFIG) + return kvm_riscv_vcpu_get_reg_config(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CORE) + return kvm_riscv_vcpu_get_reg_core(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CSR) + return kvm_riscv_vcpu_get_reg_csr(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_TIMER) + return kvm_riscv_vcpu_get_reg_timer(vcpu, reg); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_F) + return kvm_riscv_vcpu_get_reg_fp(vcpu, reg, + KVM_REG_RISCV_FP_F); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_D) + return kvm_riscv_vcpu_get_reg_fp(vcpu, reg, + KVM_REG_RISCV_FP_D); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_ISA_EXT) + return kvm_riscv_vcpu_get_reg_isa_ext(vcpu, reg); + + return -EINVAL; +} + +long kvm_arch_vcpu_async_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + struct kvm_vcpu *vcpu = filp->private_data; + void __user *argp = (void __user *)arg; + + if (ioctl == KVM_INTERRUPT) { + struct kvm_interrupt irq; + + if (copy_from_user(&irq, argp, sizeof(irq))) + return -EFAULT; + + if (irq.irq == KVM_INTERRUPT_SET) + return kvm_riscv_vcpu_set_interrupt(vcpu, IRQ_VS_EXT); + else + return kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT); + } + + return -ENOIOCTLCMD; +} + +long kvm_arch_vcpu_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + struct kvm_vcpu *vcpu = filp->private_data; + void __user *argp = (void __user *)arg; + long r = -EINVAL; + + switch (ioctl) { + case KVM_SET_ONE_REG: + case KVM_GET_ONE_REG: { + struct kvm_one_reg reg; + + r = -EFAULT; + if (copy_from_user(®, argp, sizeof(reg))) + break; + + if (ioctl == KVM_SET_ONE_REG) + r = kvm_riscv_vcpu_set_reg(vcpu, ®); + else + r = kvm_riscv_vcpu_get_reg(vcpu, ®); + break; + } + default: + break; + } + + return r; +} + +int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, + struct kvm_translation *tr) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + return -EINVAL; +} + +void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + unsigned long mask, val; + + if (READ_ONCE(vcpu->arch.irqs_pending_mask)) { + mask = xchg_acquire(&vcpu->arch.irqs_pending_mask, 0); + val = READ_ONCE(vcpu->arch.irqs_pending) & mask; + + csr->hvip &= ~mask; + csr->hvip |= val; + } +} + +void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu) +{ + unsigned long hvip; + struct kvm_vcpu_arch *v = &vcpu->arch; + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + + /* Read current HVIP and VSIE CSRs */ + csr->vsie = csr_read(CSR_VSIE); + + /* Sync-up HVIP.VSSIP bit changes does by Guest */ + hvip = csr_read(CSR_HVIP); + if ((csr->hvip ^ hvip) & (1UL << IRQ_VS_SOFT)) { + if (hvip & (1UL << IRQ_VS_SOFT)) { + if (!test_and_set_bit(IRQ_VS_SOFT, + &v->irqs_pending_mask)) + set_bit(IRQ_VS_SOFT, &v->irqs_pending); + } else { + if (!test_and_set_bit(IRQ_VS_SOFT, + &v->irqs_pending_mask)) + clear_bit(IRQ_VS_SOFT, &v->irqs_pending); + } + } + + /* Sync-up timer CSRs */ + kvm_riscv_vcpu_timer_sync(vcpu); +} + +int kvm_riscv_vcpu_set_interrupt(struct kvm_vcpu *vcpu, unsigned int irq) +{ + if (irq != IRQ_VS_SOFT && + irq != IRQ_VS_TIMER && + irq != IRQ_VS_EXT) + return -EINVAL; + + set_bit(irq, &vcpu->arch.irqs_pending); + smp_mb__before_atomic(); + set_bit(irq, &vcpu->arch.irqs_pending_mask); + + kvm_vcpu_kick(vcpu); + + return 0; +} + +int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq) +{ + if (irq != IRQ_VS_SOFT && + irq != IRQ_VS_TIMER && + irq != IRQ_VS_EXT) + return -EINVAL; + + clear_bit(irq, &vcpu->arch.irqs_pending); + smp_mb__before_atomic(); + set_bit(irq, &vcpu->arch.irqs_pending_mask); + + return 0; +} + +bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, unsigned long mask) +{ + unsigned long ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK) + << VSIP_TO_HVIP_SHIFT) & mask; + + return (READ_ONCE(vcpu->arch.irqs_pending) & ie) ? true : false; +} + +void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu) +{ + vcpu->arch.power_off = true; + kvm_make_request(KVM_REQ_SLEEP, vcpu); + kvm_vcpu_kick(vcpu); +} + +void kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu) +{ + vcpu->arch.power_off = false; + kvm_vcpu_wake_up(vcpu); +} + +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + if (vcpu->arch.power_off) + mp_state->mp_state = KVM_MP_STATE_STOPPED; + else + mp_state->mp_state = KVM_MP_STATE_RUNNABLE; + + return 0; +} + +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + int ret = 0; + + switch (mp_state->mp_state) { + case KVM_MP_STATE_RUNNABLE: + vcpu->arch.power_off = false; + break; + case KVM_MP_STATE_STOPPED: + kvm_riscv_vcpu_power_off(vcpu); + break; + default: + ret = -EINVAL; + } + + return ret; +} + +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + /* TODO; To be implemented later. */ + return -EINVAL; +} + +static void kvm_riscv_vcpu_update_config(const unsigned long *isa) +{ + u64 henvcfg = 0; + + if (riscv_isa_extension_available(isa, SVPBMT)) + henvcfg |= ENVCFG_PBMTE; + + if (riscv_isa_extension_available(isa, SSTC)) + henvcfg |= ENVCFG_STCE; + + if (riscv_isa_extension_available(isa, ZICBOM)) + henvcfg |= (ENVCFG_CBIE | ENVCFG_CBCFE); + + csr_write(CSR_HENVCFG, henvcfg); +#ifdef CONFIG_32BIT + csr_write(CSR_HENVCFGH, henvcfg >> 32); +#endif +} + +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + + csr_write(CSR_VSSTATUS, csr->vsstatus); + csr_write(CSR_VSIE, csr->vsie); + csr_write(CSR_VSTVEC, csr->vstvec); + csr_write(CSR_VSSCRATCH, csr->vsscratch); + csr_write(CSR_VSEPC, csr->vsepc); + csr_write(CSR_VSCAUSE, csr->vscause); + csr_write(CSR_VSTVAL, csr->vstval); + csr_write(CSR_HVIP, csr->hvip); + csr_write(CSR_VSATP, csr->vsatp); + + kvm_riscv_vcpu_update_config(vcpu->arch.isa); + + kvm_riscv_gstage_update_hgatp(vcpu); + + kvm_riscv_vcpu_timer_restore(vcpu); + + kvm_riscv_vcpu_host_fp_save(&vcpu->arch.host_context); + kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context, + vcpu->arch.isa); + + vcpu->cpu = cpu; +} + +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + + vcpu->cpu = -1; + + kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context, + vcpu->arch.isa); + kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context); + + kvm_riscv_vcpu_timer_save(vcpu); + + csr->vsstatus = csr_read(CSR_VSSTATUS); + csr->vsie = csr_read(CSR_VSIE); + csr->vstvec = csr_read(CSR_VSTVEC); + csr->vsscratch = csr_read(CSR_VSSCRATCH); + csr->vsepc = csr_read(CSR_VSEPC); + csr->vscause = csr_read(CSR_VSCAUSE); + csr->vstval = csr_read(CSR_VSTVAL); + csr->hvip = csr_read(CSR_HVIP); + csr->vsatp = csr_read(CSR_VSATP); +} + +static void kvm_riscv_check_vcpu_requests(struct kvm_vcpu *vcpu) +{ + struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); + + if (kvm_request_pending(vcpu)) { + if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) { + kvm_vcpu_srcu_read_unlock(vcpu); + rcuwait_wait_event(wait, + (!vcpu->arch.power_off) && (!vcpu->arch.pause), + TASK_INTERRUPTIBLE); + kvm_vcpu_srcu_read_lock(vcpu); + + if (vcpu->arch.power_off || vcpu->arch.pause) { + /* + * Awaken to handle a signal, request to + * sleep again later. + */ + kvm_make_request(KVM_REQ_SLEEP, vcpu); + } + } + + if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) + kvm_riscv_reset_vcpu(vcpu); + + if (kvm_check_request(KVM_REQ_UPDATE_HGATP, vcpu)) + kvm_riscv_gstage_update_hgatp(vcpu); + + if (kvm_check_request(KVM_REQ_FENCE_I, vcpu)) + kvm_riscv_fence_i_process(vcpu); + + /* + * The generic KVM_REQ_TLB_FLUSH is same as + * KVM_REQ_HFENCE_GVMA_VMID_ALL + */ + if (kvm_check_request(KVM_REQ_HFENCE_GVMA_VMID_ALL, vcpu)) + kvm_riscv_hfence_gvma_vmid_all_process(vcpu); + + if (kvm_check_request(KVM_REQ_HFENCE_VVMA_ALL, vcpu)) + kvm_riscv_hfence_vvma_all_process(vcpu); + + if (kvm_check_request(KVM_REQ_HFENCE, vcpu)) + kvm_riscv_hfence_process(vcpu); + } +} + +static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + + csr_write(CSR_HVIP, csr->hvip); +} + +/* + * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while + * the vCPU is running. + * + * This must be noinstr as instrumentation may make use of RCU, and this is not + * safe during the EQS. + */ +static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu) +{ + guest_state_enter_irqoff(); + __kvm_riscv_switch_to(&vcpu->arch); + vcpu->arch.last_exit_cpu = vcpu->cpu; + guest_state_exit_irqoff(); +} + +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) +{ + int ret; + struct kvm_cpu_trap trap; + struct kvm_run *run = vcpu->run; + + /* Mark this VCPU ran at least once */ + vcpu->arch.ran_atleast_once = true; + + kvm_vcpu_srcu_read_lock(vcpu); + + switch (run->exit_reason) { + case KVM_EXIT_MMIO: + /* Process MMIO value returned from user-space */ + ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run); + break; + case KVM_EXIT_RISCV_SBI: + /* Process SBI value returned from user-space */ + ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run); + break; + case KVM_EXIT_RISCV_CSR: + /* Process CSR value returned from user-space */ + ret = kvm_riscv_vcpu_csr_return(vcpu, vcpu->run); + break; + default: + ret = 0; + break; + } + if (ret) { + kvm_vcpu_srcu_read_unlock(vcpu); + return ret; + } + + if (run->immediate_exit) { + kvm_vcpu_srcu_read_unlock(vcpu); + return -EINTR; + } + + vcpu_load(vcpu); + + kvm_sigset_activate(vcpu); + + ret = 1; + run->exit_reason = KVM_EXIT_UNKNOWN; + while (ret > 0) { + /* Check conditions before entering the guest */ + ret = xfer_to_guest_mode_handle_work(vcpu); + if (!ret) + ret = 1; + + kvm_riscv_gstage_vmid_update(vcpu); + + kvm_riscv_check_vcpu_requests(vcpu); + + local_irq_disable(); + + /* + * Ensure we set mode to IN_GUEST_MODE after we disable + * interrupts and before the final VCPU requests check. + * See the comment in kvm_vcpu_exiting_guest_mode() and + * Documentation/virt/kvm/vcpu-requests.rst + */ + vcpu->mode = IN_GUEST_MODE; + + kvm_vcpu_srcu_read_unlock(vcpu); + smp_mb__after_srcu_read_unlock(); + + /* + * We might have got VCPU interrupts updated asynchronously + * so update it in HW. + */ + kvm_riscv_vcpu_flush_interrupts(vcpu); + + /* Update HVIP CSR for current CPU */ + kvm_riscv_update_hvip(vcpu); + + if (ret <= 0 || + kvm_riscv_gstage_vmid_ver_changed(&vcpu->kvm->arch.vmid) || + kvm_request_pending(vcpu) || + xfer_to_guest_mode_work_pending()) { + vcpu->mode = OUTSIDE_GUEST_MODE; + local_irq_enable(); + kvm_vcpu_srcu_read_lock(vcpu); + continue; + } + + /* + * Cleanup stale TLB enteries + * + * Note: This should be done after G-stage VMID has been + * updated using kvm_riscv_gstage_vmid_ver_changed() + */ + kvm_riscv_local_tlb_sanitize(vcpu); + + guest_timing_enter_irqoff(); + + kvm_riscv_vcpu_enter_exit(vcpu); + + vcpu->mode = OUTSIDE_GUEST_MODE; + vcpu->stat.exits++; + + /* + * Save SCAUSE, STVAL, HTVAL, and HTINST because we might + * get an interrupt between __kvm_riscv_switch_to() and + * local_irq_enable() which can potentially change CSRs. + */ + trap.sepc = vcpu->arch.guest_context.sepc; + trap.scause = csr_read(CSR_SCAUSE); + trap.stval = csr_read(CSR_STVAL); + trap.htval = csr_read(CSR_HTVAL); + trap.htinst = csr_read(CSR_HTINST); + + /* Syncup interrupts state with HW */ + kvm_riscv_vcpu_sync_interrupts(vcpu); + + preempt_disable(); + + /* + * We must ensure that any pending interrupts are taken before + * we exit guest timing so that timer ticks are accounted as + * guest time. Transiently unmask interrupts so that any + * pending interrupts are taken. + * + * There's no barrier which ensures that pending interrupts are + * recognised, so we just hope that the CPU takes any pending + * interrupts between the enable and disable. + */ + local_irq_enable(); + local_irq_disable(); + + guest_timing_exit_irqoff(); + + local_irq_enable(); + + preempt_enable(); + + kvm_vcpu_srcu_read_lock(vcpu); + + ret = kvm_riscv_vcpu_exit(vcpu, run, &trap); + } + + kvm_sigset_deactivate(vcpu); + + vcpu_put(vcpu); + + kvm_vcpu_srcu_read_unlock(vcpu); + + return ret; +} diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c new file mode 100644 index 000000000..c9f741ab2 --- /dev/null +++ b/arch/riscv/kvm/vcpu_exit.c @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/insn-def.h> + +static int gstage_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_cpu_trap *trap) +{ + struct kvm_memory_slot *memslot; + unsigned long hva, fault_addr; + bool writable; + gfn_t gfn; + int ret; + + fault_addr = (trap->htval << 2) | (trap->stval & 0x3); + gfn = fault_addr >> PAGE_SHIFT; + memslot = gfn_to_memslot(vcpu->kvm, gfn); + hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable); + + if (kvm_is_error_hva(hva) || + (trap->scause == EXC_STORE_GUEST_PAGE_FAULT && !writable)) { + switch (trap->scause) { + case EXC_LOAD_GUEST_PAGE_FAULT: + return kvm_riscv_vcpu_mmio_load(vcpu, run, + fault_addr, + trap->htinst); + case EXC_STORE_GUEST_PAGE_FAULT: + return kvm_riscv_vcpu_mmio_store(vcpu, run, + fault_addr, + trap->htinst); + default: + return -EOPNOTSUPP; + }; + } + + ret = kvm_riscv_gstage_map(vcpu, memslot, fault_addr, hva, + (trap->scause == EXC_STORE_GUEST_PAGE_FAULT) ? true : false); + if (ret < 0) + return ret; + + return 1; +} + +/** + * kvm_riscv_vcpu_unpriv_read -- Read machine word from Guest memory + * + * @vcpu: The VCPU pointer + * @read_insn: Flag representing whether we are reading instruction + * @guest_addr: Guest address to read + * @trap: Output pointer to trap details + */ +unsigned long kvm_riscv_vcpu_unpriv_read(struct kvm_vcpu *vcpu, + bool read_insn, + unsigned long guest_addr, + struct kvm_cpu_trap *trap) +{ + register unsigned long taddr asm("a0") = (unsigned long)trap; + register unsigned long ttmp asm("a1"); + unsigned long flags, val, tmp, old_stvec, old_hstatus; + + local_irq_save(flags); + + old_hstatus = csr_swap(CSR_HSTATUS, vcpu->arch.guest_context.hstatus); + old_stvec = csr_swap(CSR_STVEC, (ulong)&__kvm_riscv_unpriv_trap); + + if (read_insn) { + /* + * HLVX.HU instruction + * 0110010 00011 rs1 100 rd 1110011 + */ + asm volatile ("\n" + ".option push\n" + ".option norvc\n" + "add %[ttmp], %[taddr], 0\n" + HLVX_HU(%[val], %[addr]) + "andi %[tmp], %[val], 3\n" + "addi %[tmp], %[tmp], -3\n" + "bne %[tmp], zero, 2f\n" + "addi %[addr], %[addr], 2\n" + HLVX_HU(%[tmp], %[addr]) + "sll %[tmp], %[tmp], 16\n" + "add %[val], %[val], %[tmp]\n" + "2:\n" + ".option pop" + : [val] "=&r" (val), [tmp] "=&r" (tmp), + [taddr] "+&r" (taddr), [ttmp] "+&r" (ttmp), + [addr] "+&r" (guest_addr) : : "memory"); + + if (trap->scause == EXC_LOAD_PAGE_FAULT) + trap->scause = EXC_INST_PAGE_FAULT; + } else { + /* + * HLV.D instruction + * 0110110 00000 rs1 100 rd 1110011 + * + * HLV.W instruction + * 0110100 00000 rs1 100 rd 1110011 + */ + asm volatile ("\n" + ".option push\n" + ".option norvc\n" + "add %[ttmp], %[taddr], 0\n" +#ifdef CONFIG_64BIT + HLV_D(%[val], %[addr]) +#else + HLV_W(%[val], %[addr]) +#endif + ".option pop" + : [val] "=&r" (val), + [taddr] "+&r" (taddr), [ttmp] "+&r" (ttmp) + : [addr] "r" (guest_addr) : "memory"); + } + + csr_write(CSR_STVEC, old_stvec); + csr_write(CSR_HSTATUS, old_hstatus); + + local_irq_restore(flags); + + return val; +} + +/** + * kvm_riscv_vcpu_trap_redirect -- Redirect trap to Guest + * + * @vcpu: The VCPU pointer + * @trap: Trap details + */ +void kvm_riscv_vcpu_trap_redirect(struct kvm_vcpu *vcpu, + struct kvm_cpu_trap *trap) +{ + unsigned long vsstatus = csr_read(CSR_VSSTATUS); + + /* Change Guest SSTATUS.SPP bit */ + vsstatus &= ~SR_SPP; + if (vcpu->arch.guest_context.sstatus & SR_SPP) + vsstatus |= SR_SPP; + + /* Change Guest SSTATUS.SPIE bit */ + vsstatus &= ~SR_SPIE; + if (vsstatus & SR_SIE) + vsstatus |= SR_SPIE; + + /* Clear Guest SSTATUS.SIE bit */ + vsstatus &= ~SR_SIE; + + /* Update Guest SSTATUS */ + csr_write(CSR_VSSTATUS, vsstatus); + + /* Update Guest SCAUSE, STVAL, and SEPC */ + csr_write(CSR_VSCAUSE, trap->scause); + csr_write(CSR_VSTVAL, trap->stval); + csr_write(CSR_VSEPC, trap->sepc); + + /* Set Guest PC to Guest exception vector */ + vcpu->arch.guest_context.sepc = csr_read(CSR_VSTVEC); +} + +/* + * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on + * proper exit to userspace. + */ +int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_cpu_trap *trap) +{ + int ret; + + /* If we got host interrupt then do nothing */ + if (trap->scause & CAUSE_IRQ_FLAG) + return 1; + + /* Handle guest traps */ + ret = -EFAULT; + run->exit_reason = KVM_EXIT_UNKNOWN; + switch (trap->scause) { + case EXC_VIRTUAL_INST_FAULT: + if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) + ret = kvm_riscv_vcpu_virtual_insn(vcpu, run, trap); + break; + case EXC_INST_GUEST_PAGE_FAULT: + case EXC_LOAD_GUEST_PAGE_FAULT: + case EXC_STORE_GUEST_PAGE_FAULT: + if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) + ret = gstage_page_fault(vcpu, run, trap); + break; + case EXC_SUPERVISOR_SYSCALL: + if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) + ret = kvm_riscv_vcpu_sbi_ecall(vcpu, run); + break; + default: + break; + } + + /* Print details in-case of error */ + if (ret < 0) { + kvm_err("VCPU exit error %d\n", ret); + kvm_err("SEPC=0x%lx SSTATUS=0x%lx HSTATUS=0x%lx\n", + vcpu->arch.guest_context.sepc, + vcpu->arch.guest_context.sstatus, + vcpu->arch.guest_context.hstatus); + kvm_err("SCAUSE=0x%lx STVAL=0x%lx HTVAL=0x%lx HTINST=0x%lx\n", + trap->scause, trap->stval, trap->htval, trap->htinst); + } + + return ret; +} diff --git a/arch/riscv/kvm/vcpu_fp.c b/arch/riscv/kvm/vcpu_fp.c new file mode 100644 index 000000000..9d8cbc420 --- /dev/null +++ b/arch/riscv/kvm/vcpu_fp.c @@ -0,0 +1,165 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <linux/uaccess.h> +#include <asm/hwcap.h> + +#ifdef CONFIG_FPU +void kvm_riscv_vcpu_fp_reset(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + + cntx->sstatus &= ~SR_FS; + if (riscv_isa_extension_available(vcpu->arch.isa, f) || + riscv_isa_extension_available(vcpu->arch.isa, d)) + cntx->sstatus |= SR_FS_INITIAL; + else + cntx->sstatus |= SR_FS_OFF; +} + +static void kvm_riscv_vcpu_fp_clean(struct kvm_cpu_context *cntx) +{ + cntx->sstatus &= ~SR_FS; + cntx->sstatus |= SR_FS_CLEAN; +} + +void kvm_riscv_vcpu_guest_fp_save(struct kvm_cpu_context *cntx, + const unsigned long *isa) +{ + if ((cntx->sstatus & SR_FS) == SR_FS_DIRTY) { + if (riscv_isa_extension_available(isa, d)) + __kvm_riscv_fp_d_save(cntx); + else if (riscv_isa_extension_available(isa, f)) + __kvm_riscv_fp_f_save(cntx); + kvm_riscv_vcpu_fp_clean(cntx); + } +} + +void kvm_riscv_vcpu_guest_fp_restore(struct kvm_cpu_context *cntx, + const unsigned long *isa) +{ + if ((cntx->sstatus & SR_FS) != SR_FS_OFF) { + if (riscv_isa_extension_available(isa, d)) + __kvm_riscv_fp_d_restore(cntx); + else if (riscv_isa_extension_available(isa, f)) + __kvm_riscv_fp_f_restore(cntx); + kvm_riscv_vcpu_fp_clean(cntx); + } +} + +void kvm_riscv_vcpu_host_fp_save(struct kvm_cpu_context *cntx) +{ + /* No need to check host sstatus as it can be modified outside */ + if (riscv_isa_extension_available(NULL, d)) + __kvm_riscv_fp_d_save(cntx); + else if (riscv_isa_extension_available(NULL, f)) + __kvm_riscv_fp_f_save(cntx); +} + +void kvm_riscv_vcpu_host_fp_restore(struct kvm_cpu_context *cntx) +{ + if (riscv_isa_extension_available(NULL, d)) + __kvm_riscv_fp_d_restore(cntx); + else if (riscv_isa_extension_available(NULL, f)) + __kvm_riscv_fp_f_restore(cntx); +} +#endif + +int kvm_riscv_vcpu_get_reg_fp(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype) +{ + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + rtype); + void *reg_val; + + if ((rtype == KVM_REG_RISCV_FP_F) && + riscv_isa_extension_available(vcpu->arch.isa, f)) { + if (KVM_REG_SIZE(reg->id) != sizeof(u32)) + return -EINVAL; + if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr)) + reg_val = &cntx->fp.f.fcsr; + else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) && + reg_num <= KVM_REG_RISCV_FP_F_REG(f[31])) + reg_val = &cntx->fp.f.f[reg_num]; + else + return -EINVAL; + } else if ((rtype == KVM_REG_RISCV_FP_D) && + riscv_isa_extension_available(vcpu->arch.isa, d)) { + if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) { + if (KVM_REG_SIZE(reg->id) != sizeof(u32)) + return -EINVAL; + reg_val = &cntx->fp.d.fcsr; + } else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) && + reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) { + if (KVM_REG_SIZE(reg->id) != sizeof(u64)) + return -EINVAL; + reg_val = &cntx->fp.d.f[reg_num]; + } else + return -EINVAL; + } else + return -EINVAL; + + if (copy_to_user(uaddr, reg_val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +int kvm_riscv_vcpu_set_reg_fp(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype) +{ + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + rtype); + void *reg_val; + + if ((rtype == KVM_REG_RISCV_FP_F) && + riscv_isa_extension_available(vcpu->arch.isa, f)) { + if (KVM_REG_SIZE(reg->id) != sizeof(u32)) + return -EINVAL; + if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr)) + reg_val = &cntx->fp.f.fcsr; + else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) && + reg_num <= KVM_REG_RISCV_FP_F_REG(f[31])) + reg_val = &cntx->fp.f.f[reg_num]; + else + return -EINVAL; + } else if ((rtype == KVM_REG_RISCV_FP_D) && + riscv_isa_extension_available(vcpu->arch.isa, d)) { + if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) { + if (KVM_REG_SIZE(reg->id) != sizeof(u32)) + return -EINVAL; + reg_val = &cntx->fp.d.fcsr; + } else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) && + reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) { + if (KVM_REG_SIZE(reg->id) != sizeof(u64)) + return -EINVAL; + reg_val = &cntx->fp.d.f[reg_num]; + } else + return -EINVAL; + } else + return -EINVAL; + + if (copy_from_user(reg_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} diff --git a/arch/riscv/kvm/vcpu_insn.c b/arch/riscv/kvm/vcpu_insn.c new file mode 100644 index 000000000..0bb52761a --- /dev/null +++ b/arch/riscv/kvm/vcpu_insn.c @@ -0,0 +1,751 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * Copyright (c) 2022 Ventana Micro Systems Inc. + */ + +#include <linux/bitops.h> +#include <linux/kvm_host.h> + +#define INSN_OPCODE_MASK 0x007c +#define INSN_OPCODE_SHIFT 2 +#define INSN_OPCODE_SYSTEM 28 + +#define INSN_MASK_WFI 0xffffffff +#define INSN_MATCH_WFI 0x10500073 + +#define INSN_MATCH_CSRRW 0x1073 +#define INSN_MASK_CSRRW 0x707f +#define INSN_MATCH_CSRRS 0x2073 +#define INSN_MASK_CSRRS 0x707f +#define INSN_MATCH_CSRRC 0x3073 +#define INSN_MASK_CSRRC 0x707f +#define INSN_MATCH_CSRRWI 0x5073 +#define INSN_MASK_CSRRWI 0x707f +#define INSN_MATCH_CSRRSI 0x6073 +#define INSN_MASK_CSRRSI 0x707f +#define INSN_MATCH_CSRRCI 0x7073 +#define INSN_MASK_CSRRCI 0x707f + +#define INSN_MATCH_LB 0x3 +#define INSN_MASK_LB 0x707f +#define INSN_MATCH_LH 0x1003 +#define INSN_MASK_LH 0x707f +#define INSN_MATCH_LW 0x2003 +#define INSN_MASK_LW 0x707f +#define INSN_MATCH_LD 0x3003 +#define INSN_MASK_LD 0x707f +#define INSN_MATCH_LBU 0x4003 +#define INSN_MASK_LBU 0x707f +#define INSN_MATCH_LHU 0x5003 +#define INSN_MASK_LHU 0x707f +#define INSN_MATCH_LWU 0x6003 +#define INSN_MASK_LWU 0x707f +#define INSN_MATCH_SB 0x23 +#define INSN_MASK_SB 0x707f +#define INSN_MATCH_SH 0x1023 +#define INSN_MASK_SH 0x707f +#define INSN_MATCH_SW 0x2023 +#define INSN_MASK_SW 0x707f +#define INSN_MATCH_SD 0x3023 +#define INSN_MASK_SD 0x707f + +#define INSN_MATCH_C_LD 0x6000 +#define INSN_MASK_C_LD 0xe003 +#define INSN_MATCH_C_SD 0xe000 +#define INSN_MASK_C_SD 0xe003 +#define INSN_MATCH_C_LW 0x4000 +#define INSN_MASK_C_LW 0xe003 +#define INSN_MATCH_C_SW 0xc000 +#define INSN_MASK_C_SW 0xe003 +#define INSN_MATCH_C_LDSP 0x6002 +#define INSN_MASK_C_LDSP 0xe003 +#define INSN_MATCH_C_SDSP 0xe002 +#define INSN_MASK_C_SDSP 0xe003 +#define INSN_MATCH_C_LWSP 0x4002 +#define INSN_MASK_C_LWSP 0xe003 +#define INSN_MATCH_C_SWSP 0xc002 +#define INSN_MASK_C_SWSP 0xe003 + +#define INSN_16BIT_MASK 0x3 + +#define INSN_IS_16BIT(insn) (((insn) & INSN_16BIT_MASK) != INSN_16BIT_MASK) + +#define INSN_LEN(insn) (INSN_IS_16BIT(insn) ? 2 : 4) + +#ifdef CONFIG_64BIT +#define LOG_REGBYTES 3 +#else +#define LOG_REGBYTES 2 +#endif +#define REGBYTES (1 << LOG_REGBYTES) + +#define SH_RD 7 +#define SH_RS1 15 +#define SH_RS2 20 +#define SH_RS2C 2 +#define MASK_RX 0x1f + +#define RV_X(x, s, n) (((x) >> (s)) & ((1 << (n)) - 1)) +#define RVC_LW_IMM(x) ((RV_X(x, 6, 1) << 2) | \ + (RV_X(x, 10, 3) << 3) | \ + (RV_X(x, 5, 1) << 6)) +#define RVC_LD_IMM(x) ((RV_X(x, 10, 3) << 3) | \ + (RV_X(x, 5, 2) << 6)) +#define RVC_LWSP_IMM(x) ((RV_X(x, 4, 3) << 2) | \ + (RV_X(x, 12, 1) << 5) | \ + (RV_X(x, 2, 2) << 6)) +#define RVC_LDSP_IMM(x) ((RV_X(x, 5, 2) << 3) | \ + (RV_X(x, 12, 1) << 5) | \ + (RV_X(x, 2, 3) << 6)) +#define RVC_SWSP_IMM(x) ((RV_X(x, 9, 4) << 2) | \ + (RV_X(x, 7, 2) << 6)) +#define RVC_SDSP_IMM(x) ((RV_X(x, 10, 3) << 3) | \ + (RV_X(x, 7, 3) << 6)) +#define RVC_RS1S(insn) (8 + RV_X(insn, SH_RD, 3)) +#define RVC_RS2S(insn) (8 + RV_X(insn, SH_RS2C, 3)) +#define RVC_RS2(insn) RV_X(insn, SH_RS2C, 5) + +#define SHIFT_RIGHT(x, y) \ + ((y) < 0 ? ((x) << -(y)) : ((x) >> (y))) + +#define REG_MASK \ + ((1 << (5 + LOG_REGBYTES)) - (1 << LOG_REGBYTES)) + +#define REG_OFFSET(insn, pos) \ + (SHIFT_RIGHT((insn), (pos) - LOG_REGBYTES) & REG_MASK) + +#define REG_PTR(insn, pos, regs) \ + ((ulong *)((ulong)(regs) + REG_OFFSET(insn, pos))) + +#define GET_FUNCT3(insn) (((insn) >> 12) & 7) + +#define GET_RS1(insn, regs) (*REG_PTR(insn, SH_RS1, regs)) +#define GET_RS2(insn, regs) (*REG_PTR(insn, SH_RS2, regs)) +#define GET_RS1S(insn, regs) (*REG_PTR(RVC_RS1S(insn), 0, regs)) +#define GET_RS2S(insn, regs) (*REG_PTR(RVC_RS2S(insn), 0, regs)) +#define GET_RS2C(insn, regs) (*REG_PTR(insn, SH_RS2C, regs)) +#define GET_SP(regs) (*REG_PTR(2, 0, regs)) +#define SET_RD(insn, regs, val) (*REG_PTR(insn, SH_RD, regs) = (val)) +#define IMM_I(insn) ((s32)(insn) >> 20) +#define IMM_S(insn) (((s32)(insn) >> 25 << 5) | \ + (s32)(((insn) >> 7) & 0x1f)) + +struct insn_func { + unsigned long mask; + unsigned long match; + /* + * Possible return values are as follows: + * 1) Returns < 0 for error case + * 2) Returns 0 for exit to user-space + * 3) Returns 1 to continue with next sepc + * 4) Returns 2 to continue with same sepc + * 5) Returns 3 to inject illegal instruction trap and continue + * 6) Returns 4 to inject virtual instruction trap and continue + * + * Use enum kvm_insn_return for return values + */ + int (*func)(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn); +}; + +static int truly_illegal_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, + ulong insn) +{ + struct kvm_cpu_trap utrap = { 0 }; + + /* Redirect trap to Guest VCPU */ + utrap.sepc = vcpu->arch.guest_context.sepc; + utrap.scause = EXC_INST_ILLEGAL; + utrap.stval = insn; + utrap.htval = 0; + utrap.htinst = 0; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + + return 1; +} + +static int truly_virtual_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, + ulong insn) +{ + struct kvm_cpu_trap utrap = { 0 }; + + /* Redirect trap to Guest VCPU */ + utrap.sepc = vcpu->arch.guest_context.sepc; + utrap.scause = EXC_VIRTUAL_INST_FAULT; + utrap.stval = insn; + utrap.htval = 0; + utrap.htinst = 0; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + + return 1; +} + +/** + * kvm_riscv_vcpu_wfi -- Emulate wait for interrupt (WFI) behaviour + * + * @vcpu: The VCPU pointer + */ +void kvm_riscv_vcpu_wfi(struct kvm_vcpu *vcpu) +{ + if (!kvm_arch_vcpu_runnable(vcpu)) { + kvm_vcpu_srcu_read_unlock(vcpu); + kvm_vcpu_halt(vcpu); + kvm_vcpu_srcu_read_lock(vcpu); + } +} + +static int wfi_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn) +{ + vcpu->stat.wfi_exit_stat++; + kvm_riscv_vcpu_wfi(vcpu); + return KVM_INSN_CONTINUE_NEXT_SEPC; +} + +struct csr_func { + unsigned int base; + unsigned int count; + /* + * Possible return values are as same as "func" callback in + * "struct insn_func". + */ + int (*func)(struct kvm_vcpu *vcpu, unsigned int csr_num, + unsigned long *val, unsigned long new_val, + unsigned long wr_mask); +}; + +static const struct csr_func csr_funcs[] = { }; + +/** + * kvm_riscv_vcpu_csr_return -- Handle CSR read/write after user space + * emulation or in-kernel emulation + * + * @vcpu: The VCPU pointer + * @run: The VCPU run struct containing the CSR data + * + * Returns > 0 upon failure and 0 upon success + */ +int kvm_riscv_vcpu_csr_return(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + ulong insn; + + if (vcpu->arch.csr_decode.return_handled) + return 0; + vcpu->arch.csr_decode.return_handled = 1; + + /* Update destination register for CSR reads */ + insn = vcpu->arch.csr_decode.insn; + if ((insn >> SH_RD) & MASK_RX) + SET_RD(insn, &vcpu->arch.guest_context, + run->riscv_csr.ret_value); + + /* Move to next instruction */ + vcpu->arch.guest_context.sepc += INSN_LEN(insn); + + return 0; +} + +static int csr_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn) +{ + int i, rc = KVM_INSN_ILLEGAL_TRAP; + unsigned int csr_num = insn >> SH_RS2; + unsigned int rs1_num = (insn >> SH_RS1) & MASK_RX; + ulong rs1_val = GET_RS1(insn, &vcpu->arch.guest_context); + const struct csr_func *tcfn, *cfn = NULL; + ulong val = 0, wr_mask = 0, new_val = 0; + + /* Decode the CSR instruction */ + switch (GET_FUNCT3(insn)) { + case GET_FUNCT3(INSN_MATCH_CSRRW): + wr_mask = -1UL; + new_val = rs1_val; + break; + case GET_FUNCT3(INSN_MATCH_CSRRS): + wr_mask = rs1_val; + new_val = -1UL; + break; + case GET_FUNCT3(INSN_MATCH_CSRRC): + wr_mask = rs1_val; + new_val = 0; + break; + case GET_FUNCT3(INSN_MATCH_CSRRWI): + wr_mask = -1UL; + new_val = rs1_num; + break; + case GET_FUNCT3(INSN_MATCH_CSRRSI): + wr_mask = rs1_num; + new_val = -1UL; + break; + case GET_FUNCT3(INSN_MATCH_CSRRCI): + wr_mask = rs1_num; + new_val = 0; + break; + default: + return rc; + } + + /* Save instruction decode info */ + vcpu->arch.csr_decode.insn = insn; + vcpu->arch.csr_decode.return_handled = 0; + + /* Update CSR details in kvm_run struct */ + run->riscv_csr.csr_num = csr_num; + run->riscv_csr.new_value = new_val; + run->riscv_csr.write_mask = wr_mask; + run->riscv_csr.ret_value = 0; + + /* Find in-kernel CSR function */ + for (i = 0; i < ARRAY_SIZE(csr_funcs); i++) { + tcfn = &csr_funcs[i]; + if ((tcfn->base <= csr_num) && + (csr_num < (tcfn->base + tcfn->count))) { + cfn = tcfn; + break; + } + } + + /* First try in-kernel CSR emulation */ + if (cfn && cfn->func) { + rc = cfn->func(vcpu, csr_num, &val, new_val, wr_mask); + if (rc > KVM_INSN_EXIT_TO_USER_SPACE) { + if (rc == KVM_INSN_CONTINUE_NEXT_SEPC) { + run->riscv_csr.ret_value = val; + vcpu->stat.csr_exit_kernel++; + kvm_riscv_vcpu_csr_return(vcpu, run); + rc = KVM_INSN_CONTINUE_SAME_SEPC; + } + return rc; + } + } + + /* Exit to user-space for CSR emulation */ + if (rc <= KVM_INSN_EXIT_TO_USER_SPACE) { + vcpu->stat.csr_exit_user++; + run->exit_reason = KVM_EXIT_RISCV_CSR; + } + + return rc; +} + +static const struct insn_func system_opcode_funcs[] = { + { + .mask = INSN_MASK_CSRRW, + .match = INSN_MATCH_CSRRW, + .func = csr_insn, + }, + { + .mask = INSN_MASK_CSRRS, + .match = INSN_MATCH_CSRRS, + .func = csr_insn, + }, + { + .mask = INSN_MASK_CSRRC, + .match = INSN_MATCH_CSRRC, + .func = csr_insn, + }, + { + .mask = INSN_MASK_CSRRWI, + .match = INSN_MATCH_CSRRWI, + .func = csr_insn, + }, + { + .mask = INSN_MASK_CSRRSI, + .match = INSN_MATCH_CSRRSI, + .func = csr_insn, + }, + { + .mask = INSN_MASK_CSRRCI, + .match = INSN_MATCH_CSRRCI, + .func = csr_insn, + }, + { + .mask = INSN_MASK_WFI, + .match = INSN_MATCH_WFI, + .func = wfi_insn, + }, +}; + +static int system_opcode_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, + ulong insn) +{ + int i, rc = KVM_INSN_ILLEGAL_TRAP; + const struct insn_func *ifn; + + for (i = 0; i < ARRAY_SIZE(system_opcode_funcs); i++) { + ifn = &system_opcode_funcs[i]; + if ((insn & ifn->mask) == ifn->match) { + rc = ifn->func(vcpu, run, insn); + break; + } + } + + switch (rc) { + case KVM_INSN_ILLEGAL_TRAP: + return truly_illegal_insn(vcpu, run, insn); + case KVM_INSN_VIRTUAL_TRAP: + return truly_virtual_insn(vcpu, run, insn); + case KVM_INSN_CONTINUE_NEXT_SEPC: + vcpu->arch.guest_context.sepc += INSN_LEN(insn); + break; + default: + break; + } + + return (rc <= 0) ? rc : 1; +} + +/** + * kvm_riscv_vcpu_virtual_insn -- Handle virtual instruction trap + * + * @vcpu: The VCPU pointer + * @run: The VCPU run struct containing the mmio data + * @trap: Trap details + * + * Returns > 0 to continue run-loop + * Returns 0 to exit run-loop and handle in user-space. + * Returns < 0 to report failure and exit run-loop + */ +int kvm_riscv_vcpu_virtual_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_cpu_trap *trap) +{ + unsigned long insn = trap->stval; + struct kvm_cpu_trap utrap = { 0 }; + struct kvm_cpu_context *ct; + + if (unlikely(INSN_IS_16BIT(insn))) { + if (insn == 0) { + ct = &vcpu->arch.guest_context; + insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, + ct->sepc, + &utrap); + if (utrap.scause) { + utrap.sepc = ct->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + return 1; + } + } + if (INSN_IS_16BIT(insn)) + return truly_illegal_insn(vcpu, run, insn); + } + + switch ((insn & INSN_OPCODE_MASK) >> INSN_OPCODE_SHIFT) { + case INSN_OPCODE_SYSTEM: + return system_opcode_insn(vcpu, run, insn); + default: + return truly_illegal_insn(vcpu, run, insn); + } +} + +/** + * kvm_riscv_vcpu_mmio_load -- Emulate MMIO load instruction + * + * @vcpu: The VCPU pointer + * @run: The VCPU run struct containing the mmio data + * @fault_addr: Guest physical address to load + * @htinst: Transformed encoding of the load instruction + * + * Returns > 0 to continue run-loop + * Returns 0 to exit run-loop and handle in user-space. + * Returns < 0 to report failure and exit run-loop + */ +int kvm_riscv_vcpu_mmio_load(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long fault_addr, + unsigned long htinst) +{ + u8 data_buf[8]; + unsigned long insn; + int shift = 0, len = 0, insn_len = 0; + struct kvm_cpu_trap utrap = { 0 }; + struct kvm_cpu_context *ct = &vcpu->arch.guest_context; + + /* Determine trapped instruction */ + if (htinst & 0x1) { + /* + * Bit[0] == 1 implies trapped instruction value is + * transformed instruction or custom instruction. + */ + insn = htinst | INSN_16BIT_MASK; + insn_len = (htinst & BIT(1)) ? INSN_LEN(insn) : 2; + } else { + /* + * Bit[0] == 0 implies trapped instruction value is + * zero or special value. + */ + insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc, + &utrap); + if (utrap.scause) { + /* Redirect trap if we failed to read instruction */ + utrap.sepc = ct->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + return 1; + } + insn_len = INSN_LEN(insn); + } + + /* Decode length of MMIO and shift */ + if ((insn & INSN_MASK_LW) == INSN_MATCH_LW) { + len = 4; + shift = 8 * (sizeof(ulong) - len); + } else if ((insn & INSN_MASK_LB) == INSN_MATCH_LB) { + len = 1; + shift = 8 * (sizeof(ulong) - len); + } else if ((insn & INSN_MASK_LBU) == INSN_MATCH_LBU) { + len = 1; + shift = 8 * (sizeof(ulong) - len); +#ifdef CONFIG_64BIT + } else if ((insn & INSN_MASK_LD) == INSN_MATCH_LD) { + len = 8; + shift = 8 * (sizeof(ulong) - len); + } else if ((insn & INSN_MASK_LWU) == INSN_MATCH_LWU) { + len = 4; +#endif + } else if ((insn & INSN_MASK_LH) == INSN_MATCH_LH) { + len = 2; + shift = 8 * (sizeof(ulong) - len); + } else if ((insn & INSN_MASK_LHU) == INSN_MATCH_LHU) { + len = 2; +#ifdef CONFIG_64BIT + } else if ((insn & INSN_MASK_C_LD) == INSN_MATCH_C_LD) { + len = 8; + shift = 8 * (sizeof(ulong) - len); + insn = RVC_RS2S(insn) << SH_RD; + } else if ((insn & INSN_MASK_C_LDSP) == INSN_MATCH_C_LDSP && + ((insn >> SH_RD) & 0x1f)) { + len = 8; + shift = 8 * (sizeof(ulong) - len); +#endif + } else if ((insn & INSN_MASK_C_LW) == INSN_MATCH_C_LW) { + len = 4; + shift = 8 * (sizeof(ulong) - len); + insn = RVC_RS2S(insn) << SH_RD; + } else if ((insn & INSN_MASK_C_LWSP) == INSN_MATCH_C_LWSP && + ((insn >> SH_RD) & 0x1f)) { + len = 4; + shift = 8 * (sizeof(ulong) - len); + } else { + return -EOPNOTSUPP; + } + + /* Fault address should be aligned to length of MMIO */ + if (fault_addr & (len - 1)) + return -EIO; + + /* Save instruction decode info */ + vcpu->arch.mmio_decode.insn = insn; + vcpu->arch.mmio_decode.insn_len = insn_len; + vcpu->arch.mmio_decode.shift = shift; + vcpu->arch.mmio_decode.len = len; + vcpu->arch.mmio_decode.return_handled = 0; + + /* Update MMIO details in kvm_run struct */ + run->mmio.is_write = false; + run->mmio.phys_addr = fault_addr; + run->mmio.len = len; + + /* Try to handle MMIO access in the kernel */ + if (!kvm_io_bus_read(vcpu, KVM_MMIO_BUS, fault_addr, len, data_buf)) { + /* Successfully handled MMIO access in the kernel so resume */ + memcpy(run->mmio.data, data_buf, len); + vcpu->stat.mmio_exit_kernel++; + kvm_riscv_vcpu_mmio_return(vcpu, run); + return 1; + } + + /* Exit to userspace for MMIO emulation */ + vcpu->stat.mmio_exit_user++; + run->exit_reason = KVM_EXIT_MMIO; + + return 0; +} + +/** + * kvm_riscv_vcpu_mmio_store -- Emulate MMIO store instruction + * + * @vcpu: The VCPU pointer + * @run: The VCPU run struct containing the mmio data + * @fault_addr: Guest physical address to store + * @htinst: Transformed encoding of the store instruction + * + * Returns > 0 to continue run-loop + * Returns 0 to exit run-loop and handle in user-space. + * Returns < 0 to report failure and exit run-loop + */ +int kvm_riscv_vcpu_mmio_store(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long fault_addr, + unsigned long htinst) +{ + u8 data8; + u16 data16; + u32 data32; + u64 data64; + ulong data; + unsigned long insn; + int len = 0, insn_len = 0; + struct kvm_cpu_trap utrap = { 0 }; + struct kvm_cpu_context *ct = &vcpu->arch.guest_context; + + /* Determine trapped instruction */ + if (htinst & 0x1) { + /* + * Bit[0] == 1 implies trapped instruction value is + * transformed instruction or custom instruction. + */ + insn = htinst | INSN_16BIT_MASK; + insn_len = (htinst & BIT(1)) ? INSN_LEN(insn) : 2; + } else { + /* + * Bit[0] == 0 implies trapped instruction value is + * zero or special value. + */ + insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc, + &utrap); + if (utrap.scause) { + /* Redirect trap if we failed to read instruction */ + utrap.sepc = ct->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + return 1; + } + insn_len = INSN_LEN(insn); + } + + data = GET_RS2(insn, &vcpu->arch.guest_context); + data8 = data16 = data32 = data64 = data; + + if ((insn & INSN_MASK_SW) == INSN_MATCH_SW) { + len = 4; + } else if ((insn & INSN_MASK_SB) == INSN_MATCH_SB) { + len = 1; +#ifdef CONFIG_64BIT + } else if ((insn & INSN_MASK_SD) == INSN_MATCH_SD) { + len = 8; +#endif + } else if ((insn & INSN_MASK_SH) == INSN_MATCH_SH) { + len = 2; +#ifdef CONFIG_64BIT + } else if ((insn & INSN_MASK_C_SD) == INSN_MATCH_C_SD) { + len = 8; + data64 = GET_RS2S(insn, &vcpu->arch.guest_context); + } else if ((insn & INSN_MASK_C_SDSP) == INSN_MATCH_C_SDSP && + ((insn >> SH_RD) & 0x1f)) { + len = 8; + data64 = GET_RS2C(insn, &vcpu->arch.guest_context); +#endif + } else if ((insn & INSN_MASK_C_SW) == INSN_MATCH_C_SW) { + len = 4; + data32 = GET_RS2S(insn, &vcpu->arch.guest_context); + } else if ((insn & INSN_MASK_C_SWSP) == INSN_MATCH_C_SWSP && + ((insn >> SH_RD) & 0x1f)) { + len = 4; + data32 = GET_RS2C(insn, &vcpu->arch.guest_context); + } else { + return -EOPNOTSUPP; + } + + /* Fault address should be aligned to length of MMIO */ + if (fault_addr & (len - 1)) + return -EIO; + + /* Save instruction decode info */ + vcpu->arch.mmio_decode.insn = insn; + vcpu->arch.mmio_decode.insn_len = insn_len; + vcpu->arch.mmio_decode.shift = 0; + vcpu->arch.mmio_decode.len = len; + vcpu->arch.mmio_decode.return_handled = 0; + + /* Copy data to kvm_run instance */ + switch (len) { + case 1: + *((u8 *)run->mmio.data) = data8; + break; + case 2: + *((u16 *)run->mmio.data) = data16; + break; + case 4: + *((u32 *)run->mmio.data) = data32; + break; + case 8: + *((u64 *)run->mmio.data) = data64; + break; + default: + return -EOPNOTSUPP; + } + + /* Update MMIO details in kvm_run struct */ + run->mmio.is_write = true; + run->mmio.phys_addr = fault_addr; + run->mmio.len = len; + + /* Try to handle MMIO access in the kernel */ + if (!kvm_io_bus_write(vcpu, KVM_MMIO_BUS, + fault_addr, len, run->mmio.data)) { + /* Successfully handled MMIO access in the kernel so resume */ + vcpu->stat.mmio_exit_kernel++; + kvm_riscv_vcpu_mmio_return(vcpu, run); + return 1; + } + + /* Exit to userspace for MMIO emulation */ + vcpu->stat.mmio_exit_user++; + run->exit_reason = KVM_EXIT_MMIO; + + return 0; +} + +/** + * kvm_riscv_vcpu_mmio_return -- Handle MMIO loads after user space emulation + * or in-kernel IO emulation + * + * @vcpu: The VCPU pointer + * @run: The VCPU run struct containing the mmio data + */ +int kvm_riscv_vcpu_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + u8 data8; + u16 data16; + u32 data32; + u64 data64; + ulong insn; + int len, shift; + + if (vcpu->arch.mmio_decode.return_handled) + return 0; + + vcpu->arch.mmio_decode.return_handled = 1; + insn = vcpu->arch.mmio_decode.insn; + + if (run->mmio.is_write) + goto done; + + len = vcpu->arch.mmio_decode.len; + shift = vcpu->arch.mmio_decode.shift; + + switch (len) { + case 1: + data8 = *((u8 *)run->mmio.data); + SET_RD(insn, &vcpu->arch.guest_context, + (ulong)data8 << shift >> shift); + break; + case 2: + data16 = *((u16 *)run->mmio.data); + SET_RD(insn, &vcpu->arch.guest_context, + (ulong)data16 << shift >> shift); + break; + case 4: + data32 = *((u32 *)run->mmio.data); + SET_RD(insn, &vcpu->arch.guest_context, + (ulong)data32 << shift >> shift); + break; + case 8: + data64 = *((u64 *)run->mmio.data); + SET_RD(insn, &vcpu->arch.guest_context, + (ulong)data64 << shift >> shift); + break; + default: + return -EOPNOTSUPP; + } + +done: + /* Move to next instruction */ + vcpu->arch.guest_context.sepc += vcpu->arch.mmio_decode.insn_len; + + return 0; +} diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c new file mode 100644 index 000000000..f96991d23 --- /dev/null +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -0,0 +1,180 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <asm/sbi.h> +#include <asm/kvm_vcpu_sbi.h> + +static int kvm_linux_err_map_sbi(int err) +{ + switch (err) { + case 0: + return SBI_SUCCESS; + case -EPERM: + return SBI_ERR_DENIED; + case -EINVAL: + return SBI_ERR_INVALID_PARAM; + case -EFAULT: + return SBI_ERR_INVALID_ADDRESS; + case -EOPNOTSUPP: + return SBI_ERR_NOT_SUPPORTED; + case -EALREADY: + return SBI_ERR_ALREADY_AVAILABLE; + default: + return SBI_ERR_FAILURE; + }; +} + +#ifndef CONFIG_RISCV_SBI_V01 +static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = { + .extid_start = -1UL, + .extid_end = -1UL, + .handler = NULL, +}; +#endif + +static const struct kvm_vcpu_sbi_extension *sbi_ext[] = { + &vcpu_sbi_ext_v01, + &vcpu_sbi_ext_base, + &vcpu_sbi_ext_time, + &vcpu_sbi_ext_ipi, + &vcpu_sbi_ext_rfence, + &vcpu_sbi_ext_srst, + &vcpu_sbi_ext_hsm, + &vcpu_sbi_ext_experimental, + &vcpu_sbi_ext_vendor, +}; + +void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + + vcpu->arch.sbi_context.return_handled = 0; + vcpu->stat.ecall_exit_stat++; + run->exit_reason = KVM_EXIT_RISCV_SBI; + run->riscv_sbi.extension_id = cp->a7; + run->riscv_sbi.function_id = cp->a6; + run->riscv_sbi.args[0] = cp->a0; + run->riscv_sbi.args[1] = cp->a1; + run->riscv_sbi.args[2] = cp->a2; + run->riscv_sbi.args[3] = cp->a3; + run->riscv_sbi.args[4] = cp->a4; + run->riscv_sbi.args[5] = cp->a5; + run->riscv_sbi.ret[0] = cp->a0; + run->riscv_sbi.ret[1] = cp->a1; +} + +void kvm_riscv_vcpu_sbi_system_reset(struct kvm_vcpu *vcpu, + struct kvm_run *run, + u32 type, u64 reason) +{ + unsigned long i; + struct kvm_vcpu *tmp; + + kvm_for_each_vcpu(i, tmp, vcpu->kvm) + tmp->arch.power_off = true; + kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP); + + memset(&run->system_event, 0, sizeof(run->system_event)); + run->system_event.type = type; + run->system_event.ndata = 1; + run->system_event.data[0] = reason; + run->exit_reason = KVM_EXIT_SYSTEM_EVENT; +} + +int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + + /* Handle SBI return only once */ + if (vcpu->arch.sbi_context.return_handled) + return 0; + vcpu->arch.sbi_context.return_handled = 1; + + /* Update return values */ + cp->a0 = run->riscv_sbi.ret[0]; + cp->a1 = run->riscv_sbi.ret[1]; + + /* Move to next instruction */ + vcpu->arch.guest_context.sepc += 4; + + return 0; +} + +const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid) +{ + int i = 0; + + for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) { + if (sbi_ext[i]->extid_start <= extid && + sbi_ext[i]->extid_end >= extid) + return sbi_ext[i]; + } + + return NULL; +} + +int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + int ret = 1; + bool next_sepc = true; + bool userspace_exit = false; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + const struct kvm_vcpu_sbi_extension *sbi_ext; + struct kvm_cpu_trap utrap = { 0 }; + unsigned long out_val = 0; + bool ext_is_v01 = false; + + sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7); + if (sbi_ext && sbi_ext->handler) { +#ifdef CONFIG_RISCV_SBI_V01 + if (cp->a7 >= SBI_EXT_0_1_SET_TIMER && + cp->a7 <= SBI_EXT_0_1_SHUTDOWN) + ext_is_v01 = true; +#endif + ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit); + } else { + /* Return error for unsupported SBI calls */ + cp->a0 = SBI_ERR_NOT_SUPPORTED; + goto ecall_done; + } + + /* Handle special error cases i.e trap, exit or userspace forward */ + if (utrap.scause) { + /* No need to increment sepc or exit ioctl loop */ + ret = 1; + utrap.sepc = cp->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + next_sepc = false; + goto ecall_done; + } + + /* Exit ioctl loop or Propagate the error code the guest */ + if (userspace_exit) { + next_sepc = false; + ret = 0; + } else { + /** + * SBI extension handler always returns an Linux error code. Convert + * it to the SBI specific error code that can be propagated the SBI + * caller. + */ + ret = kvm_linux_err_map_sbi(ret); + cp->a0 = ret; + ret = 1; + } +ecall_done: + if (next_sepc) + cp->sepc += 4; + if (!ext_is_v01) + cp->a1 = out_val; + + return ret; +} diff --git a/arch/riscv/kvm/vcpu_sbi_base.c b/arch/riscv/kvm/vcpu_sbi_base.c new file mode 100644 index 000000000..48f431091 --- /dev/null +++ b/arch/riscv/kvm/vcpu_sbi_base.c @@ -0,0 +1,100 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <linux/version.h> +#include <asm/csr.h> +#include <asm/sbi.h> +#include <asm/kvm_vcpu_timer.h> +#include <asm/kvm_vcpu_sbi.h> + +static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *trap, bool *exit) +{ + int ret = 0; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + struct sbiret ecall_ret; + + switch (cp->a6) { + case SBI_EXT_BASE_GET_SPEC_VERSION: + *out_val = (KVM_SBI_VERSION_MAJOR << + SBI_SPEC_VERSION_MAJOR_SHIFT) | + KVM_SBI_VERSION_MINOR; + break; + case SBI_EXT_BASE_GET_IMP_ID: + *out_val = KVM_SBI_IMPID; + break; + case SBI_EXT_BASE_GET_IMP_VERSION: + *out_val = LINUX_VERSION_CODE; + break; + case SBI_EXT_BASE_PROBE_EXT: + if ((cp->a0 >= SBI_EXT_EXPERIMENTAL_START && + cp->a0 <= SBI_EXT_EXPERIMENTAL_END) || + (cp->a0 >= SBI_EXT_VENDOR_START && + cp->a0 <= SBI_EXT_VENDOR_END)) { + /* + * For experimental/vendor extensions + * forward it to the userspace + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + *exit = true; + } else + *out_val = kvm_vcpu_sbi_find_ext(cp->a0) ? 1 : 0; + break; + case SBI_EXT_BASE_GET_MVENDORID: + case SBI_EXT_BASE_GET_MARCHID: + case SBI_EXT_BASE_GET_MIMPID: + ecall_ret = sbi_ecall(SBI_EXT_BASE, cp->a6, 0, 0, 0, 0, 0, 0); + if (!ecall_ret.error) + *out_val = ecall_ret.value; + /*TODO: We are unnecessarily converting the error twice */ + ret = sbi_err_map_linux_errno(ecall_ret.error); + break; + default: + ret = -EOPNOTSUPP; + break; + } + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_base = { + .extid_start = SBI_EXT_BASE, + .extid_end = SBI_EXT_BASE, + .handler = kvm_sbi_ext_base_handler, +}; + +static int kvm_sbi_ext_forward_handler(struct kvm_vcpu *vcpu, + struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, + bool *exit) +{ + /* + * Both SBI experimental and vendor extensions are + * unconditionally forwarded to userspace. + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + *exit = true; + return 0; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental = { + .extid_start = SBI_EXT_EXPERIMENTAL_START, + .extid_end = SBI_EXT_EXPERIMENTAL_END, + .handler = kvm_sbi_ext_forward_handler, +}; + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor = { + .extid_start = SBI_EXT_VENDOR_START, + .extid_end = SBI_EXT_VENDOR_END, + .handler = kvm_sbi_ext_forward_handler, +}; diff --git a/arch/riscv/kvm/vcpu_sbi_hsm.c b/arch/riscv/kvm/vcpu_sbi_hsm.c new file mode 100644 index 000000000..239dec0a6 --- /dev/null +++ b/arch/riscv/kvm/vcpu_sbi_hsm.c @@ -0,0 +1,119 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/sbi.h> +#include <asm/kvm_vcpu_sbi.h> + +static int kvm_sbi_hsm_vcpu_start(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *reset_cntx; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + struct kvm_vcpu *target_vcpu; + unsigned long target_vcpuid = cp->a0; + + target_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, target_vcpuid); + if (!target_vcpu) + return -EINVAL; + if (!target_vcpu->arch.power_off) + return -EALREADY; + + reset_cntx = &target_vcpu->arch.guest_reset_context; + /* start address */ + reset_cntx->sepc = cp->a1; + /* target vcpu id to start */ + reset_cntx->a0 = target_vcpuid; + /* private data passed from kernel */ + reset_cntx->a1 = cp->a2; + kvm_make_request(KVM_REQ_VCPU_RESET, target_vcpu); + + kvm_riscv_vcpu_power_on(target_vcpu); + + return 0; +} + +static int kvm_sbi_hsm_vcpu_stop(struct kvm_vcpu *vcpu) +{ + if (vcpu->arch.power_off) + return -EINVAL; + + kvm_riscv_vcpu_power_off(vcpu); + + return 0; +} + +static int kvm_sbi_hsm_vcpu_get_status(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long target_vcpuid = cp->a0; + struct kvm_vcpu *target_vcpu; + + target_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, target_vcpuid); + if (!target_vcpu) + return -EINVAL; + if (!target_vcpu->arch.power_off) + return SBI_HSM_STATE_STARTED; + else if (vcpu->stat.generic.blocking) + return SBI_HSM_STATE_SUSPENDED; + else + return SBI_HSM_STATE_STOPPED; +} + +static int kvm_sbi_ext_hsm_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, + bool *exit) +{ + int ret = 0; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + struct kvm *kvm = vcpu->kvm; + unsigned long funcid = cp->a6; + + switch (funcid) { + case SBI_EXT_HSM_HART_START: + mutex_lock(&kvm->lock); + ret = kvm_sbi_hsm_vcpu_start(vcpu); + mutex_unlock(&kvm->lock); + break; + case SBI_EXT_HSM_HART_STOP: + ret = kvm_sbi_hsm_vcpu_stop(vcpu); + break; + case SBI_EXT_HSM_HART_STATUS: + ret = kvm_sbi_hsm_vcpu_get_status(vcpu); + if (ret >= 0) { + *out_val = ret; + ret = 0; + } + break; + case SBI_EXT_HSM_HART_SUSPEND: + switch (cp->a0) { + case SBI_HSM_SUSPEND_RET_DEFAULT: + kvm_riscv_vcpu_wfi(vcpu); + break; + case SBI_HSM_SUSPEND_NON_RET_DEFAULT: + ret = -EOPNOTSUPP; + break; + default: + ret = -EINVAL; + } + break; + default: + ret = -EOPNOTSUPP; + } + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm = { + .extid_start = SBI_EXT_HSM, + .extid_end = SBI_EXT_HSM, + .handler = kvm_sbi_ext_hsm_handler, +}; diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c new file mode 100644 index 000000000..4c034d8a6 --- /dev/null +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -0,0 +1,174 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/sbi.h> +#include <asm/kvm_vcpu_timer.h> +#include <asm/kvm_vcpu_sbi.h> + +static int kvm_sbi_ext_time_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, bool *exit) +{ + int ret = 0; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + u64 next_cycle; + + if (cp->a6 != SBI_EXT_TIME_SET_TIMER) + return -EINVAL; + +#if __riscv_xlen == 32 + next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0; +#else + next_cycle = (u64)cp->a0; +#endif + kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_time = { + .extid_start = SBI_EXT_TIME, + .extid_end = SBI_EXT_TIME, + .handler = kvm_sbi_ext_time_handler, +}; + +static int kvm_sbi_ext_ipi_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, bool *exit) +{ + int ret = 0; + unsigned long i; + struct kvm_vcpu *tmp; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long hmask = cp->a0; + unsigned long hbase = cp->a1; + + if (cp->a6 != SBI_EXT_IPI_SEND_IPI) + return -EINVAL; + + kvm_for_each_vcpu(i, tmp, vcpu->kvm) { + if (hbase != -1UL) { + if (tmp->vcpu_id < hbase) + continue; + if (!(hmask & (1UL << (tmp->vcpu_id - hbase)))) + continue; + } + ret = kvm_riscv_vcpu_set_interrupt(tmp, IRQ_VS_SOFT); + if (ret < 0) + break; + } + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi = { + .extid_start = SBI_EXT_IPI, + .extid_end = SBI_EXT_IPI, + .handler = kvm_sbi_ext_ipi_handler, +}; + +static int kvm_sbi_ext_rfence_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, bool *exit) +{ + int ret = 0; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long hmask = cp->a0; + unsigned long hbase = cp->a1; + unsigned long funcid = cp->a6; + + switch (funcid) { + case SBI_EXT_RFENCE_REMOTE_FENCE_I: + kvm_riscv_fence_i(vcpu->kvm, hbase, hmask); + break; + case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA: + if (cp->a2 == 0 && cp->a3 == 0) + kvm_riscv_hfence_vvma_all(vcpu->kvm, hbase, hmask); + else + kvm_riscv_hfence_vvma_gva(vcpu->kvm, hbase, hmask, + cp->a2, cp->a3, PAGE_SHIFT); + break; + case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID: + if (cp->a2 == 0 && cp->a3 == 0) + kvm_riscv_hfence_vvma_asid_all(vcpu->kvm, + hbase, hmask, cp->a4); + else + kvm_riscv_hfence_vvma_asid_gva(vcpu->kvm, + hbase, hmask, + cp->a2, cp->a3, + PAGE_SHIFT, cp->a4); + break; + case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA: + case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID: + case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA: + case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID: + /* + * Until nested virtualization is implemented, the + * SBI HFENCE calls should be treated as NOPs + */ + break; + default: + ret = -EOPNOTSUPP; + } + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence = { + .extid_start = SBI_EXT_RFENCE, + .extid_end = SBI_EXT_RFENCE, + .handler = kvm_sbi_ext_rfence_handler, +}; + +static int kvm_sbi_ext_srst_handler(struct kvm_vcpu *vcpu, + struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, bool *exit) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long funcid = cp->a6; + u32 reason = cp->a1; + u32 type = cp->a0; + int ret = 0; + + switch (funcid) { + case SBI_EXT_SRST_RESET: + switch (type) { + case SBI_SRST_RESET_TYPE_SHUTDOWN: + kvm_riscv_vcpu_sbi_system_reset(vcpu, run, + KVM_SYSTEM_EVENT_SHUTDOWN, + reason); + *exit = true; + break; + case SBI_SRST_RESET_TYPE_COLD_REBOOT: + case SBI_SRST_RESET_TYPE_WARM_REBOOT: + kvm_riscv_vcpu_sbi_system_reset(vcpu, run, + KVM_SYSTEM_EVENT_RESET, + reason); + *exit = true; + break; + default: + ret = -EOPNOTSUPP; + } + break; + default: + ret = -EOPNOTSUPP; + } + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst = { + .extid_start = SBI_EXT_SRST, + .extid_end = SBI_EXT_SRST, + .handler = kvm_sbi_ext_srst_handler, +}; diff --git a/arch/riscv/kvm/vcpu_sbi_v01.c b/arch/riscv/kvm/vcpu_sbi_v01.c new file mode 100644 index 000000000..8a91a14e7 --- /dev/null +++ b/arch/riscv/kvm/vcpu_sbi_v01.c @@ -0,0 +1,118 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/sbi.h> +#include <asm/kvm_vcpu_timer.h> +#include <asm/kvm_vcpu_sbi.h> + +static int kvm_sbi_ext_v01_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, + bool *exit) +{ + ulong hmask; + int i, ret = 0; + u64 next_cycle; + struct kvm_vcpu *rvcpu; + struct kvm *kvm = vcpu->kvm; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + + switch (cp->a7) { + case SBI_EXT_0_1_CONSOLE_GETCHAR: + case SBI_EXT_0_1_CONSOLE_PUTCHAR: + /* + * The CONSOLE_GETCHAR/CONSOLE_PUTCHAR SBI calls cannot be + * handled in kernel so we forward these to user-space + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + *exit = true; + break; + case SBI_EXT_0_1_SET_TIMER: +#if __riscv_xlen == 32 + next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0; +#else + next_cycle = (u64)cp->a0; +#endif + ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); + break; + case SBI_EXT_0_1_CLEAR_IPI: + ret = kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT); + break; + case SBI_EXT_0_1_SEND_IPI: + if (cp->a0) + hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, + utrap); + else + hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; + if (utrap->scause) + break; + + for_each_set_bit(i, &hmask, BITS_PER_LONG) { + rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); + ret = kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT); + if (ret < 0) + break; + } + break; + case SBI_EXT_0_1_SHUTDOWN: + kvm_riscv_vcpu_sbi_system_reset(vcpu, run, + KVM_SYSTEM_EVENT_SHUTDOWN, 0); + *exit = true; + break; + case SBI_EXT_0_1_REMOTE_FENCE_I: + case SBI_EXT_0_1_REMOTE_SFENCE_VMA: + case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID: + if (cp->a0) + hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, + utrap); + else + hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; + if (utrap->scause) + break; + + if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I) + kvm_riscv_fence_i(vcpu->kvm, 0, hmask); + else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) { + if (cp->a1 == 0 && cp->a2 == 0) + kvm_riscv_hfence_vvma_all(vcpu->kvm, + 0, hmask); + else + kvm_riscv_hfence_vvma_gva(vcpu->kvm, + 0, hmask, + cp->a1, cp->a2, + PAGE_SHIFT); + } else { + if (cp->a1 == 0 && cp->a2 == 0) + kvm_riscv_hfence_vvma_asid_all(vcpu->kvm, + 0, hmask, + cp->a3); + else + kvm_riscv_hfence_vvma_asid_gva(vcpu->kvm, + 0, hmask, + cp->a1, cp->a2, + PAGE_SHIFT, + cp->a3); + } + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = { + .extid_start = SBI_EXT_0_1_SET_TIMER, + .extid_end = SBI_EXT_0_1_SHUTDOWN, + .handler = kvm_sbi_ext_v01_handler, +}; diff --git a/arch/riscv/kvm/vcpu_switch.S b/arch/riscv/kvm/vcpu_switch.S new file mode 100644 index 000000000..d74df8eb4 --- /dev/null +++ b/arch/riscv/kvm/vcpu_switch.S @@ -0,0 +1,408 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/linkage.h> +#include <asm/asm.h> +#include <asm/asm-offsets.h> +#include <asm/csr.h> + + .text + .altmacro + .option norelax + +ENTRY(__kvm_riscv_switch_to) + /* Save Host GPRs (except A0 and T0-T6) */ + REG_S ra, (KVM_ARCH_HOST_RA)(a0) + REG_S sp, (KVM_ARCH_HOST_SP)(a0) + REG_S gp, (KVM_ARCH_HOST_GP)(a0) + REG_S tp, (KVM_ARCH_HOST_TP)(a0) + REG_S s0, (KVM_ARCH_HOST_S0)(a0) + REG_S s1, (KVM_ARCH_HOST_S1)(a0) + REG_S a1, (KVM_ARCH_HOST_A1)(a0) + REG_S a2, (KVM_ARCH_HOST_A2)(a0) + REG_S a3, (KVM_ARCH_HOST_A3)(a0) + REG_S a4, (KVM_ARCH_HOST_A4)(a0) + REG_S a5, (KVM_ARCH_HOST_A5)(a0) + REG_S a6, (KVM_ARCH_HOST_A6)(a0) + REG_S a7, (KVM_ARCH_HOST_A7)(a0) + REG_S s2, (KVM_ARCH_HOST_S2)(a0) + REG_S s3, (KVM_ARCH_HOST_S3)(a0) + REG_S s4, (KVM_ARCH_HOST_S4)(a0) + REG_S s5, (KVM_ARCH_HOST_S5)(a0) + REG_S s6, (KVM_ARCH_HOST_S6)(a0) + REG_S s7, (KVM_ARCH_HOST_S7)(a0) + REG_S s8, (KVM_ARCH_HOST_S8)(a0) + REG_S s9, (KVM_ARCH_HOST_S9)(a0) + REG_S s10, (KVM_ARCH_HOST_S10)(a0) + REG_S s11, (KVM_ARCH_HOST_S11)(a0) + + /* Load Guest CSR values */ + REG_L t0, (KVM_ARCH_GUEST_SSTATUS)(a0) + REG_L t1, (KVM_ARCH_GUEST_HSTATUS)(a0) + REG_L t2, (KVM_ARCH_GUEST_SCOUNTEREN)(a0) + la t4, __kvm_switch_return + REG_L t5, (KVM_ARCH_GUEST_SEPC)(a0) + + /* Save Host and Restore Guest SSTATUS */ + csrrw t0, CSR_SSTATUS, t0 + + /* Save Host and Restore Guest HSTATUS */ + csrrw t1, CSR_HSTATUS, t1 + + /* Save Host and Restore Guest SCOUNTEREN */ + csrrw t2, CSR_SCOUNTEREN, t2 + + /* Save Host STVEC and change it to return path */ + csrrw t4, CSR_STVEC, t4 + + /* Save Host SSCRATCH and change it to struct kvm_vcpu_arch pointer */ + csrrw t3, CSR_SSCRATCH, a0 + + /* Restore Guest SEPC */ + csrw CSR_SEPC, t5 + + /* Store Host CSR values */ + REG_S t0, (KVM_ARCH_HOST_SSTATUS)(a0) + REG_S t1, (KVM_ARCH_HOST_HSTATUS)(a0) + REG_S t2, (KVM_ARCH_HOST_SCOUNTEREN)(a0) + REG_S t3, (KVM_ARCH_HOST_SSCRATCH)(a0) + REG_S t4, (KVM_ARCH_HOST_STVEC)(a0) + + /* Restore Guest GPRs (except A0) */ + REG_L ra, (KVM_ARCH_GUEST_RA)(a0) + REG_L sp, (KVM_ARCH_GUEST_SP)(a0) + REG_L gp, (KVM_ARCH_GUEST_GP)(a0) + REG_L tp, (KVM_ARCH_GUEST_TP)(a0) + REG_L t0, (KVM_ARCH_GUEST_T0)(a0) + REG_L t1, (KVM_ARCH_GUEST_T1)(a0) + REG_L t2, (KVM_ARCH_GUEST_T2)(a0) + REG_L s0, (KVM_ARCH_GUEST_S0)(a0) + REG_L s1, (KVM_ARCH_GUEST_S1)(a0) + REG_L a1, (KVM_ARCH_GUEST_A1)(a0) + REG_L a2, (KVM_ARCH_GUEST_A2)(a0) + REG_L a3, (KVM_ARCH_GUEST_A3)(a0) + REG_L a4, (KVM_ARCH_GUEST_A4)(a0) + REG_L a5, (KVM_ARCH_GUEST_A5)(a0) + REG_L a6, (KVM_ARCH_GUEST_A6)(a0) + REG_L a7, (KVM_ARCH_GUEST_A7)(a0) + REG_L s2, (KVM_ARCH_GUEST_S2)(a0) + REG_L s3, (KVM_ARCH_GUEST_S3)(a0) + REG_L s4, (KVM_ARCH_GUEST_S4)(a0) + REG_L s5, (KVM_ARCH_GUEST_S5)(a0) + REG_L s6, (KVM_ARCH_GUEST_S6)(a0) + REG_L s7, (KVM_ARCH_GUEST_S7)(a0) + REG_L s8, (KVM_ARCH_GUEST_S8)(a0) + REG_L s9, (KVM_ARCH_GUEST_S9)(a0) + REG_L s10, (KVM_ARCH_GUEST_S10)(a0) + REG_L s11, (KVM_ARCH_GUEST_S11)(a0) + REG_L t3, (KVM_ARCH_GUEST_T3)(a0) + REG_L t4, (KVM_ARCH_GUEST_T4)(a0) + REG_L t5, (KVM_ARCH_GUEST_T5)(a0) + REG_L t6, (KVM_ARCH_GUEST_T6)(a0) + + /* Restore Guest A0 */ + REG_L a0, (KVM_ARCH_GUEST_A0)(a0) + + /* Resume Guest */ + sret + + /* Back to Host */ + .align 2 +__kvm_switch_return: + /* Swap Guest A0 with SSCRATCH */ + csrrw a0, CSR_SSCRATCH, a0 + + /* Save Guest GPRs (except A0) */ + REG_S ra, (KVM_ARCH_GUEST_RA)(a0) + REG_S sp, (KVM_ARCH_GUEST_SP)(a0) + REG_S gp, (KVM_ARCH_GUEST_GP)(a0) + REG_S tp, (KVM_ARCH_GUEST_TP)(a0) + REG_S t0, (KVM_ARCH_GUEST_T0)(a0) + REG_S t1, (KVM_ARCH_GUEST_T1)(a0) + REG_S t2, (KVM_ARCH_GUEST_T2)(a0) + REG_S s0, (KVM_ARCH_GUEST_S0)(a0) + REG_S s1, (KVM_ARCH_GUEST_S1)(a0) + REG_S a1, (KVM_ARCH_GUEST_A1)(a0) + REG_S a2, (KVM_ARCH_GUEST_A2)(a0) + REG_S a3, (KVM_ARCH_GUEST_A3)(a0) + REG_S a4, (KVM_ARCH_GUEST_A4)(a0) + REG_S a5, (KVM_ARCH_GUEST_A5)(a0) + REG_S a6, (KVM_ARCH_GUEST_A6)(a0) + REG_S a7, (KVM_ARCH_GUEST_A7)(a0) + REG_S s2, (KVM_ARCH_GUEST_S2)(a0) + REG_S s3, (KVM_ARCH_GUEST_S3)(a0) + REG_S s4, (KVM_ARCH_GUEST_S4)(a0) + REG_S s5, (KVM_ARCH_GUEST_S5)(a0) + REG_S s6, (KVM_ARCH_GUEST_S6)(a0) + REG_S s7, (KVM_ARCH_GUEST_S7)(a0) + REG_S s8, (KVM_ARCH_GUEST_S8)(a0) + REG_S s9, (KVM_ARCH_GUEST_S9)(a0) + REG_S s10, (KVM_ARCH_GUEST_S10)(a0) + REG_S s11, (KVM_ARCH_GUEST_S11)(a0) + REG_S t3, (KVM_ARCH_GUEST_T3)(a0) + REG_S t4, (KVM_ARCH_GUEST_T4)(a0) + REG_S t5, (KVM_ARCH_GUEST_T5)(a0) + REG_S t6, (KVM_ARCH_GUEST_T6)(a0) + + /* Load Host CSR values */ + REG_L t1, (KVM_ARCH_HOST_STVEC)(a0) + REG_L t2, (KVM_ARCH_HOST_SSCRATCH)(a0) + REG_L t3, (KVM_ARCH_HOST_SCOUNTEREN)(a0) + REG_L t4, (KVM_ARCH_HOST_HSTATUS)(a0) + REG_L t5, (KVM_ARCH_HOST_SSTATUS)(a0) + + /* Save Guest SEPC */ + csrr t0, CSR_SEPC + + /* Save Guest A0 and Restore Host SSCRATCH */ + csrrw t2, CSR_SSCRATCH, t2 + + /* Restore Host STVEC */ + csrw CSR_STVEC, t1 + + /* Save Guest and Restore Host SCOUNTEREN */ + csrrw t3, CSR_SCOUNTEREN, t3 + + /* Save Guest and Restore Host HSTATUS */ + csrrw t4, CSR_HSTATUS, t4 + + /* Save Guest and Restore Host SSTATUS */ + csrrw t5, CSR_SSTATUS, t5 + + /* Store Guest CSR values */ + REG_S t0, (KVM_ARCH_GUEST_SEPC)(a0) + REG_S t2, (KVM_ARCH_GUEST_A0)(a0) + REG_S t3, (KVM_ARCH_GUEST_SCOUNTEREN)(a0) + REG_S t4, (KVM_ARCH_GUEST_HSTATUS)(a0) + REG_S t5, (KVM_ARCH_GUEST_SSTATUS)(a0) + + /* Restore Host GPRs (except A0 and T0-T6) */ + REG_L ra, (KVM_ARCH_HOST_RA)(a0) + REG_L sp, (KVM_ARCH_HOST_SP)(a0) + REG_L gp, (KVM_ARCH_HOST_GP)(a0) + REG_L tp, (KVM_ARCH_HOST_TP)(a0) + REG_L s0, (KVM_ARCH_HOST_S0)(a0) + REG_L s1, (KVM_ARCH_HOST_S1)(a0) + REG_L a1, (KVM_ARCH_HOST_A1)(a0) + REG_L a2, (KVM_ARCH_HOST_A2)(a0) + REG_L a3, (KVM_ARCH_HOST_A3)(a0) + REG_L a4, (KVM_ARCH_HOST_A4)(a0) + REG_L a5, (KVM_ARCH_HOST_A5)(a0) + REG_L a6, (KVM_ARCH_HOST_A6)(a0) + REG_L a7, (KVM_ARCH_HOST_A7)(a0) + REG_L s2, (KVM_ARCH_HOST_S2)(a0) + REG_L s3, (KVM_ARCH_HOST_S3)(a0) + REG_L s4, (KVM_ARCH_HOST_S4)(a0) + REG_L s5, (KVM_ARCH_HOST_S5)(a0) + REG_L s6, (KVM_ARCH_HOST_S6)(a0) + REG_L s7, (KVM_ARCH_HOST_S7)(a0) + REG_L s8, (KVM_ARCH_HOST_S8)(a0) + REG_L s9, (KVM_ARCH_HOST_S9)(a0) + REG_L s10, (KVM_ARCH_HOST_S10)(a0) + REG_L s11, (KVM_ARCH_HOST_S11)(a0) + + /* Return to C code */ + ret +ENDPROC(__kvm_riscv_switch_to) + +ENTRY(__kvm_riscv_unpriv_trap) + /* + * We assume that faulting unpriv load/store instruction is + * 4-byte long and blindly increment SEPC by 4. + * + * The trap details will be saved at address pointed by 'A0' + * register and we use 'A1' register as temporary. + */ + csrr a1, CSR_SEPC + REG_S a1, (KVM_ARCH_TRAP_SEPC)(a0) + addi a1, a1, 4 + csrw CSR_SEPC, a1 + csrr a1, CSR_SCAUSE + REG_S a1, (KVM_ARCH_TRAP_SCAUSE)(a0) + csrr a1, CSR_STVAL + REG_S a1, (KVM_ARCH_TRAP_STVAL)(a0) + csrr a1, CSR_HTVAL + REG_S a1, (KVM_ARCH_TRAP_HTVAL)(a0) + csrr a1, CSR_HTINST + REG_S a1, (KVM_ARCH_TRAP_HTINST)(a0) + sret +ENDPROC(__kvm_riscv_unpriv_trap) + +#ifdef CONFIG_FPU + .align 3 + .global __kvm_riscv_fp_f_save +__kvm_riscv_fp_f_save: + csrr t2, CSR_SSTATUS + li t1, SR_FS + csrs CSR_SSTATUS, t1 + frcsr t0 + fsw f0, KVM_ARCH_FP_F_F0(a0) + fsw f1, KVM_ARCH_FP_F_F1(a0) + fsw f2, KVM_ARCH_FP_F_F2(a0) + fsw f3, KVM_ARCH_FP_F_F3(a0) + fsw f4, KVM_ARCH_FP_F_F4(a0) + fsw f5, KVM_ARCH_FP_F_F5(a0) + fsw f6, KVM_ARCH_FP_F_F6(a0) + fsw f7, KVM_ARCH_FP_F_F7(a0) + fsw f8, KVM_ARCH_FP_F_F8(a0) + fsw f9, KVM_ARCH_FP_F_F9(a0) + fsw f10, KVM_ARCH_FP_F_F10(a0) + fsw f11, KVM_ARCH_FP_F_F11(a0) + fsw f12, KVM_ARCH_FP_F_F12(a0) + fsw f13, KVM_ARCH_FP_F_F13(a0) + fsw f14, KVM_ARCH_FP_F_F14(a0) + fsw f15, KVM_ARCH_FP_F_F15(a0) + fsw f16, KVM_ARCH_FP_F_F16(a0) + fsw f17, KVM_ARCH_FP_F_F17(a0) + fsw f18, KVM_ARCH_FP_F_F18(a0) + fsw f19, KVM_ARCH_FP_F_F19(a0) + fsw f20, KVM_ARCH_FP_F_F20(a0) + fsw f21, KVM_ARCH_FP_F_F21(a0) + fsw f22, KVM_ARCH_FP_F_F22(a0) + fsw f23, KVM_ARCH_FP_F_F23(a0) + fsw f24, KVM_ARCH_FP_F_F24(a0) + fsw f25, KVM_ARCH_FP_F_F25(a0) + fsw f26, KVM_ARCH_FP_F_F26(a0) + fsw f27, KVM_ARCH_FP_F_F27(a0) + fsw f28, KVM_ARCH_FP_F_F28(a0) + fsw f29, KVM_ARCH_FP_F_F29(a0) + fsw f30, KVM_ARCH_FP_F_F30(a0) + fsw f31, KVM_ARCH_FP_F_F31(a0) + sw t0, KVM_ARCH_FP_F_FCSR(a0) + csrw CSR_SSTATUS, t2 + ret + + .align 3 + .global __kvm_riscv_fp_d_save +__kvm_riscv_fp_d_save: + csrr t2, CSR_SSTATUS + li t1, SR_FS + csrs CSR_SSTATUS, t1 + frcsr t0 + fsd f0, KVM_ARCH_FP_D_F0(a0) + fsd f1, KVM_ARCH_FP_D_F1(a0) + fsd f2, KVM_ARCH_FP_D_F2(a0) + fsd f3, KVM_ARCH_FP_D_F3(a0) + fsd f4, KVM_ARCH_FP_D_F4(a0) + fsd f5, KVM_ARCH_FP_D_F5(a0) + fsd f6, KVM_ARCH_FP_D_F6(a0) + fsd f7, KVM_ARCH_FP_D_F7(a0) + fsd f8, KVM_ARCH_FP_D_F8(a0) + fsd f9, KVM_ARCH_FP_D_F9(a0) + fsd f10, KVM_ARCH_FP_D_F10(a0) + fsd f11, KVM_ARCH_FP_D_F11(a0) + fsd f12, KVM_ARCH_FP_D_F12(a0) + fsd f13, KVM_ARCH_FP_D_F13(a0) + fsd f14, KVM_ARCH_FP_D_F14(a0) + fsd f15, KVM_ARCH_FP_D_F15(a0) + fsd f16, KVM_ARCH_FP_D_F16(a0) + fsd f17, KVM_ARCH_FP_D_F17(a0) + fsd f18, KVM_ARCH_FP_D_F18(a0) + fsd f19, KVM_ARCH_FP_D_F19(a0) + fsd f20, KVM_ARCH_FP_D_F20(a0) + fsd f21, KVM_ARCH_FP_D_F21(a0) + fsd f22, KVM_ARCH_FP_D_F22(a0) + fsd f23, KVM_ARCH_FP_D_F23(a0) + fsd f24, KVM_ARCH_FP_D_F24(a0) + fsd f25, KVM_ARCH_FP_D_F25(a0) + fsd f26, KVM_ARCH_FP_D_F26(a0) + fsd f27, KVM_ARCH_FP_D_F27(a0) + fsd f28, KVM_ARCH_FP_D_F28(a0) + fsd f29, KVM_ARCH_FP_D_F29(a0) + fsd f30, KVM_ARCH_FP_D_F30(a0) + fsd f31, KVM_ARCH_FP_D_F31(a0) + sw t0, KVM_ARCH_FP_D_FCSR(a0) + csrw CSR_SSTATUS, t2 + ret + + .align 3 + .global __kvm_riscv_fp_f_restore +__kvm_riscv_fp_f_restore: + csrr t2, CSR_SSTATUS + li t1, SR_FS + lw t0, KVM_ARCH_FP_F_FCSR(a0) + csrs CSR_SSTATUS, t1 + flw f0, KVM_ARCH_FP_F_F0(a0) + flw f1, KVM_ARCH_FP_F_F1(a0) + flw f2, KVM_ARCH_FP_F_F2(a0) + flw f3, KVM_ARCH_FP_F_F3(a0) + flw f4, KVM_ARCH_FP_F_F4(a0) + flw f5, KVM_ARCH_FP_F_F5(a0) + flw f6, KVM_ARCH_FP_F_F6(a0) + flw f7, KVM_ARCH_FP_F_F7(a0) + flw f8, KVM_ARCH_FP_F_F8(a0) + flw f9, KVM_ARCH_FP_F_F9(a0) + flw f10, KVM_ARCH_FP_F_F10(a0) + flw f11, KVM_ARCH_FP_F_F11(a0) + flw f12, KVM_ARCH_FP_F_F12(a0) + flw f13, KVM_ARCH_FP_F_F13(a0) + flw f14, KVM_ARCH_FP_F_F14(a0) + flw f15, KVM_ARCH_FP_F_F15(a0) + flw f16, KVM_ARCH_FP_F_F16(a0) + flw f17, KVM_ARCH_FP_F_F17(a0) + flw f18, KVM_ARCH_FP_F_F18(a0) + flw f19, KVM_ARCH_FP_F_F19(a0) + flw f20, KVM_ARCH_FP_F_F20(a0) + flw f21, KVM_ARCH_FP_F_F21(a0) + flw f22, KVM_ARCH_FP_F_F22(a0) + flw f23, KVM_ARCH_FP_F_F23(a0) + flw f24, KVM_ARCH_FP_F_F24(a0) + flw f25, KVM_ARCH_FP_F_F25(a0) + flw f26, KVM_ARCH_FP_F_F26(a0) + flw f27, KVM_ARCH_FP_F_F27(a0) + flw f28, KVM_ARCH_FP_F_F28(a0) + flw f29, KVM_ARCH_FP_F_F29(a0) + flw f30, KVM_ARCH_FP_F_F30(a0) + flw f31, KVM_ARCH_FP_F_F31(a0) + fscsr t0 + csrw CSR_SSTATUS, t2 + ret + + .align 3 + .global __kvm_riscv_fp_d_restore +__kvm_riscv_fp_d_restore: + csrr t2, CSR_SSTATUS + li t1, SR_FS + lw t0, KVM_ARCH_FP_D_FCSR(a0) + csrs CSR_SSTATUS, t1 + fld f0, KVM_ARCH_FP_D_F0(a0) + fld f1, KVM_ARCH_FP_D_F1(a0) + fld f2, KVM_ARCH_FP_D_F2(a0) + fld f3, KVM_ARCH_FP_D_F3(a0) + fld f4, KVM_ARCH_FP_D_F4(a0) + fld f5, KVM_ARCH_FP_D_F5(a0) + fld f6, KVM_ARCH_FP_D_F6(a0) + fld f7, KVM_ARCH_FP_D_F7(a0) + fld f8, KVM_ARCH_FP_D_F8(a0) + fld f9, KVM_ARCH_FP_D_F9(a0) + fld f10, KVM_ARCH_FP_D_F10(a0) + fld f11, KVM_ARCH_FP_D_F11(a0) + fld f12, KVM_ARCH_FP_D_F12(a0) + fld f13, KVM_ARCH_FP_D_F13(a0) + fld f14, KVM_ARCH_FP_D_F14(a0) + fld f15, KVM_ARCH_FP_D_F15(a0) + fld f16, KVM_ARCH_FP_D_F16(a0) + fld f17, KVM_ARCH_FP_D_F17(a0) + fld f18, KVM_ARCH_FP_D_F18(a0) + fld f19, KVM_ARCH_FP_D_F19(a0) + fld f20, KVM_ARCH_FP_D_F20(a0) + fld f21, KVM_ARCH_FP_D_F21(a0) + fld f22, KVM_ARCH_FP_D_F22(a0) + fld f23, KVM_ARCH_FP_D_F23(a0) + fld f24, KVM_ARCH_FP_D_F24(a0) + fld f25, KVM_ARCH_FP_D_F25(a0) + fld f26, KVM_ARCH_FP_D_F26(a0) + fld f27, KVM_ARCH_FP_D_F27(a0) + fld f28, KVM_ARCH_FP_D_F28(a0) + fld f29, KVM_ARCH_FP_D_F29(a0) + fld f30, KVM_ARCH_FP_D_F30(a0) + fld f31, KVM_ARCH_FP_D_F31(a0) + fscsr t0 + csrw CSR_SSTATUS, t2 + ret +#endif diff --git a/arch/riscv/kvm/vcpu_timer.c b/arch/riscv/kvm/vcpu_timer.c new file mode 100644 index 000000000..3ac2ff6a6 --- /dev/null +++ b/arch/riscv/kvm/vcpu_timer.c @@ -0,0 +1,362 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <linux/uaccess.h> +#include <clocksource/timer-riscv.h> +#include <asm/csr.h> +#include <asm/delay.h> +#include <asm/kvm_vcpu_timer.h> + +static u64 kvm_riscv_current_cycles(struct kvm_guest_timer *gt) +{ + return get_cycles64() + gt->time_delta; +} + +static u64 kvm_riscv_delta_cycles2ns(u64 cycles, + struct kvm_guest_timer *gt, + struct kvm_vcpu_timer *t) +{ + unsigned long flags; + u64 cycles_now, cycles_delta, delta_ns; + + local_irq_save(flags); + cycles_now = kvm_riscv_current_cycles(gt); + if (cycles_now < cycles) + cycles_delta = cycles - cycles_now; + else + cycles_delta = 0; + delta_ns = (cycles_delta * gt->nsec_mult) >> gt->nsec_shift; + local_irq_restore(flags); + + return delta_ns; +} + +static enum hrtimer_restart kvm_riscv_vcpu_hrtimer_expired(struct hrtimer *h) +{ + u64 delta_ns; + struct kvm_vcpu_timer *t = container_of(h, struct kvm_vcpu_timer, hrt); + struct kvm_vcpu *vcpu = container_of(t, struct kvm_vcpu, arch.timer); + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + + if (kvm_riscv_current_cycles(gt) < t->next_cycles) { + delta_ns = kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t); + hrtimer_forward_now(&t->hrt, ktime_set(0, delta_ns)); + return HRTIMER_RESTART; + } + + t->next_set = false; + kvm_riscv_vcpu_set_interrupt(vcpu, IRQ_VS_TIMER); + + return HRTIMER_NORESTART; +} + +static int kvm_riscv_vcpu_timer_cancel(struct kvm_vcpu_timer *t) +{ + if (!t->init_done || !t->next_set) + return -EINVAL; + + hrtimer_cancel(&t->hrt); + t->next_set = false; + + return 0; +} + +static int kvm_riscv_vcpu_update_vstimecmp(struct kvm_vcpu *vcpu, u64 ncycles) +{ +#if defined(CONFIG_32BIT) + csr_write(CSR_VSTIMECMP, ncycles & 0xFFFFFFFF); + csr_write(CSR_VSTIMECMPH, ncycles >> 32); +#else + csr_write(CSR_VSTIMECMP, ncycles); +#endif + return 0; +} + +static int kvm_riscv_vcpu_update_hrtimer(struct kvm_vcpu *vcpu, u64 ncycles) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + u64 delta_ns; + + if (!t->init_done) + return -EINVAL; + + kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_TIMER); + + delta_ns = kvm_riscv_delta_cycles2ns(ncycles, gt, t); + t->next_cycles = ncycles; + hrtimer_start(&t->hrt, ktime_set(0, delta_ns), HRTIMER_MODE_REL); + t->next_set = true; + + return 0; +} + +int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + return t->timer_next_event(vcpu, ncycles); +} + +static enum hrtimer_restart kvm_riscv_vcpu_vstimer_expired(struct hrtimer *h) +{ + u64 delta_ns; + struct kvm_vcpu_timer *t = container_of(h, struct kvm_vcpu_timer, hrt); + struct kvm_vcpu *vcpu = container_of(t, struct kvm_vcpu, arch.timer); + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + + if (kvm_riscv_current_cycles(gt) < t->next_cycles) { + delta_ns = kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t); + hrtimer_forward_now(&t->hrt, ktime_set(0, delta_ns)); + return HRTIMER_RESTART; + } + + t->next_set = false; + kvm_vcpu_kick(vcpu); + + return HRTIMER_NORESTART; +} + +bool kvm_riscv_vcpu_timer_pending(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + + if (!kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t) || + kvm_riscv_vcpu_has_interrupts(vcpu, 1UL << IRQ_VS_TIMER)) + return true; + else + return false; +} + +static void kvm_riscv_vcpu_timer_blocking(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + u64 delta_ns; + + if (!t->init_done) + return; + + delta_ns = kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t); + hrtimer_start(&t->hrt, ktime_set(0, delta_ns), HRTIMER_MODE_REL); + t->next_set = true; +} + +static void kvm_riscv_vcpu_timer_unblocking(struct kvm_vcpu *vcpu) +{ + kvm_riscv_vcpu_timer_cancel(&vcpu->arch.timer); +} + +int kvm_riscv_vcpu_get_reg_timer(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + u64 __user *uaddr = (u64 __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_TIMER); + u64 reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(u64)) + return -EINVAL; + if (reg_num >= sizeof(struct kvm_riscv_timer) / sizeof(u64)) + return -EINVAL; + + switch (reg_num) { + case KVM_REG_RISCV_TIMER_REG(frequency): + reg_val = riscv_timebase; + break; + case KVM_REG_RISCV_TIMER_REG(time): + reg_val = kvm_riscv_current_cycles(gt); + break; + case KVM_REG_RISCV_TIMER_REG(compare): + reg_val = t->next_cycles; + break; + case KVM_REG_RISCV_TIMER_REG(state): + reg_val = (t->next_set) ? KVM_RISCV_TIMER_STATE_ON : + KVM_RISCV_TIMER_STATE_OFF; + break; + default: + return -EINVAL; + } + + if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +int kvm_riscv_vcpu_set_reg_timer(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + u64 __user *uaddr = (u64 __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_TIMER); + u64 reg_val; + int ret = 0; + + if (KVM_REG_SIZE(reg->id) != sizeof(u64)) + return -EINVAL; + if (reg_num >= sizeof(struct kvm_riscv_timer) / sizeof(u64)) + return -EINVAL; + + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + switch (reg_num) { + case KVM_REG_RISCV_TIMER_REG(frequency): + ret = -EOPNOTSUPP; + break; + case KVM_REG_RISCV_TIMER_REG(time): + gt->time_delta = reg_val - get_cycles64(); + break; + case KVM_REG_RISCV_TIMER_REG(compare): + t->next_cycles = reg_val; + break; + case KVM_REG_RISCV_TIMER_REG(state): + if (reg_val == KVM_RISCV_TIMER_STATE_ON) + ret = kvm_riscv_vcpu_timer_next_event(vcpu, reg_val); + else + ret = kvm_riscv_vcpu_timer_cancel(t); + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +int kvm_riscv_vcpu_timer_init(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + if (t->init_done) + return -EINVAL; + + hrtimer_init(&t->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + t->init_done = true; + t->next_set = false; + + /* Enable sstc for every vcpu if available in hardware */ + if (riscv_isa_extension_available(NULL, SSTC)) { + t->sstc_enabled = true; + t->hrt.function = kvm_riscv_vcpu_vstimer_expired; + t->timer_next_event = kvm_riscv_vcpu_update_vstimecmp; + } else { + t->sstc_enabled = false; + t->hrt.function = kvm_riscv_vcpu_hrtimer_expired; + t->timer_next_event = kvm_riscv_vcpu_update_hrtimer; + } + + return 0; +} + +int kvm_riscv_vcpu_timer_deinit(struct kvm_vcpu *vcpu) +{ + int ret; + + ret = kvm_riscv_vcpu_timer_cancel(&vcpu->arch.timer); + vcpu->arch.timer.init_done = false; + + return ret; +} + +int kvm_riscv_vcpu_timer_reset(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + t->next_cycles = -1ULL; + return kvm_riscv_vcpu_timer_cancel(&vcpu->arch.timer); +} + +static void kvm_riscv_vcpu_update_timedelta(struct kvm_vcpu *vcpu) +{ + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + +#if defined(CONFIG_32BIT) + csr_write(CSR_HTIMEDELTA, (u32)(gt->time_delta)); + csr_write(CSR_HTIMEDELTAH, (u32)(gt->time_delta >> 32)); +#else + csr_write(CSR_HTIMEDELTA, gt->time_delta); +#endif +} + +void kvm_riscv_vcpu_timer_restore(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + kvm_riscv_vcpu_update_timedelta(vcpu); + + if (!t->sstc_enabled) + return; + +#if defined(CONFIG_32BIT) + csr_write(CSR_VSTIMECMP, (u32)t->next_cycles); + csr_write(CSR_VSTIMECMPH, (u32)(t->next_cycles >> 32)); +#else + csr_write(CSR_VSTIMECMP, t->next_cycles); +#endif + + /* timer should be enabled for the remaining operations */ + if (unlikely(!t->init_done)) + return; + + kvm_riscv_vcpu_timer_unblocking(vcpu); +} + +void kvm_riscv_vcpu_timer_sync(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + if (!t->sstc_enabled) + return; + +#if defined(CONFIG_32BIT) + t->next_cycles = csr_read(CSR_VSTIMECMP); + t->next_cycles |= (u64)csr_read(CSR_VSTIMECMPH) << 32; +#else + t->next_cycles = csr_read(CSR_VSTIMECMP); +#endif +} + +void kvm_riscv_vcpu_timer_save(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + if (!t->sstc_enabled) + return; + + /* + * The vstimecmp CSRs are saved by kvm_riscv_vcpu_timer_sync() + * upon every VM exit so no need to save here. + */ + + /* timer should be enabled for the remaining operations */ + if (unlikely(!t->init_done)) + return; + + if (kvm_vcpu_is_blocking(vcpu)) + kvm_riscv_vcpu_timer_blocking(vcpu); +} + +void kvm_riscv_guest_timer_init(struct kvm *kvm) +{ + struct kvm_guest_timer *gt = &kvm->arch.timer; + + riscv_cs_get_mult_shift(>->nsec_mult, >->nsec_shift); + gt->time_delta = -get_cycles64(); +} diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c new file mode 100644 index 000000000..65a964d7e --- /dev/null +++ b/arch/riscv/kvm/vm.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/kvm_host.h> + +const struct _kvm_stats_desc kvm_vm_stats_desc[] = { + KVM_GENERIC_VM_STATS() +}; +static_assert(ARRAY_SIZE(kvm_vm_stats_desc) == + sizeof(struct kvm_vm_stat) / sizeof(u64)); + +const struct kvm_stats_header kvm_vm_stats_header = { + .name_size = KVM_STATS_NAME_SIZE, + .num_desc = ARRAY_SIZE(kvm_vm_stats_desc), + .id_offset = sizeof(struct kvm_stats_header), + .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE, + .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE + + sizeof(kvm_vm_stats_desc), +}; + +int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) +{ + int r; + + r = kvm_riscv_gstage_alloc_pgd(kvm); + if (r) + return r; + + r = kvm_riscv_gstage_vmid_init(kvm); + if (r) { + kvm_riscv_gstage_free_pgd(kvm); + return r; + } + + kvm_riscv_guest_timer_init(kvm); + + return 0; +} + +void kvm_arch_destroy_vm(struct kvm *kvm) +{ + kvm_destroy_vcpus(kvm); +} + +int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) +{ + int r; + + switch (ext) { + case KVM_CAP_IOEVENTFD: + case KVM_CAP_DEVICE_CTRL: + case KVM_CAP_USER_MEMORY: + case KVM_CAP_SYNC_MMU: + case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: + case KVM_CAP_ONE_REG: + case KVM_CAP_READONLY_MEM: + case KVM_CAP_MP_STATE: + case KVM_CAP_IMMEDIATE_EXIT: + r = 1; + break; + case KVM_CAP_NR_VCPUS: + r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS); + break; + case KVM_CAP_MAX_VCPUS: + r = KVM_MAX_VCPUS; + break; + case KVM_CAP_NR_MEMSLOTS: + r = KVM_USER_MEM_SLOTS; + break; + case KVM_CAP_VM_GPA_BITS: + r = kvm_riscv_gstage_gpa_bits(); + break; + default: + r = 0; + break; + } + + return r; +} + +long kvm_arch_vm_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + return -EINVAL; +} diff --git a/arch/riscv/kvm/vmid.c b/arch/riscv/kvm/vmid.c new file mode 100644 index 000000000..6cd93995f --- /dev/null +++ b/arch/riscv/kvm/vmid.c @@ -0,0 +1,124 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/bitops.h> +#include <linux/cpumask.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/smp.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> + +static unsigned long vmid_version = 1; +static unsigned long vmid_next; +static unsigned long vmid_bits; +static DEFINE_SPINLOCK(vmid_lock); + +void kvm_riscv_gstage_vmid_detect(void) +{ + unsigned long old; + + /* Figure-out number of VMID bits in HW */ + old = csr_read(CSR_HGATP); + csr_write(CSR_HGATP, old | HGATP_VMID_MASK); + vmid_bits = csr_read(CSR_HGATP); + vmid_bits = (vmid_bits & HGATP_VMID_MASK) >> HGATP_VMID_SHIFT; + vmid_bits = fls_long(vmid_bits); + csr_write(CSR_HGATP, old); + + /* We polluted local TLB so flush all guest TLB */ + kvm_riscv_local_hfence_gvma_all(); + + /* We don't use VMID bits if they are not sufficient */ + if ((1UL << vmid_bits) < num_possible_cpus()) + vmid_bits = 0; +} + +unsigned long kvm_riscv_gstage_vmid_bits(void) +{ + return vmid_bits; +} + +int kvm_riscv_gstage_vmid_init(struct kvm *kvm) +{ + /* Mark the initial VMID and VMID version invalid */ + kvm->arch.vmid.vmid_version = 0; + kvm->arch.vmid.vmid = 0; + + return 0; +} + +bool kvm_riscv_gstage_vmid_ver_changed(struct kvm_vmid *vmid) +{ + if (!vmid_bits) + return false; + + return unlikely(READ_ONCE(vmid->vmid_version) != + READ_ONCE(vmid_version)); +} + +static void __local_hfence_gvma_all(void *info) +{ + kvm_riscv_local_hfence_gvma_all(); +} + +void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) +{ + unsigned long i; + struct kvm_vcpu *v; + struct kvm_vmid *vmid = &vcpu->kvm->arch.vmid; + + if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) + return; + + spin_lock(&vmid_lock); + + /* + * We need to re-check the vmid_version here to ensure that if + * another vcpu already allocated a valid vmid for this vm. + */ + if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) { + spin_unlock(&vmid_lock); + return; + } + + /* First user of a new VMID version? */ + if (unlikely(vmid_next == 0)) { + WRITE_ONCE(vmid_version, READ_ONCE(vmid_version) + 1); + vmid_next = 1; + + /* + * We ran out of VMIDs so we increment vmid_version and + * start assigning VMIDs from 1. + * + * This also means existing VMIDs assignment to all Guest + * instances is invalid and we have force VMID re-assignement + * for all Guest instances. The Guest instances that were not + * running will automatically pick-up new VMIDs because will + * call kvm_riscv_gstage_vmid_update() whenever they enter + * in-kernel run loop. For Guest instances that are already + * running, we force VM exits on all host CPUs using IPI and + * flush all Guest TLBs. + */ + on_each_cpu_mask(cpu_online_mask, __local_hfence_gvma_all, + NULL, 1); + } + + vmid->vmid = vmid_next; + vmid_next++; + vmid_next &= (1 << vmid_bits) - 1; + + WRITE_ONCE(vmid->vmid_version, READ_ONCE(vmid_version)); + + spin_unlock(&vmid_lock); + + /* Request G-stage page table update for all VCPUs */ + kvm_for_each_vcpu(i, v, vcpu->kvm) + kvm_make_request(KVM_REQ_UPDATE_HGATP, v); +} |