diff options
Diffstat (limited to 'tools/testing/selftests/kvm/lib/ucall.c')
| -rw-r--r-- | tools/testing/selftests/kvm/lib/ucall.c | 157 |
1 files changed, 0 insertions, 157 deletions
diff --git a/tools/testing/selftests/kvm/lib/ucall.c b/tools/testing/selftests/kvm/lib/ucall.c deleted file mode 100644 index dd9a66700f96..000000000000 --- a/tools/testing/selftests/kvm/lib/ucall.c +++ /dev/null @@ -1,157 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * ucall support. A ucall is a "hypercall to userspace". - * - * Copyright (C) 2018, Red Hat, Inc. - */ -#include "kvm_util.h" -#include "kvm_util_internal.h" - -#define UCALL_PIO_PORT ((uint16_t)0x1000) - -static ucall_type_t ucall_type; -static vm_vaddr_t *ucall_exit_mmio_addr; - -static bool ucall_mmio_init(struct kvm_vm *vm, vm_paddr_t gpa) -{ - if (kvm_userspace_memory_region_find(vm, gpa, gpa + 1)) - return false; - - virt_pg_map(vm, gpa, gpa, 0); - - ucall_exit_mmio_addr = (vm_vaddr_t *)gpa; - sync_global_to_guest(vm, ucall_exit_mmio_addr); - - return true; -} - -void ucall_init(struct kvm_vm *vm, ucall_type_t type, void *arg) -{ - ucall_type = type; - sync_global_to_guest(vm, ucall_type); - - if (type == UCALL_PIO) - return; - - if (type == UCALL_MMIO) { - vm_paddr_t gpa, start, end, step, offset; - unsigned bits; - bool ret; - - if (arg) { - gpa = (vm_paddr_t)arg; - ret = ucall_mmio_init(vm, gpa); - TEST_ASSERT(ret, "Can't set ucall mmio address to %lx", gpa); - return; - } - - /* - * Find an address within the allowed physical and virtual address - * spaces, that does _not_ have a KVM memory region associated with - * it. Identity mapping an address like this allows the guest to - * access it, but as KVM doesn't know what to do with it, it - * will assume it's something userspace handles and exit with - * KVM_EXIT_MMIO. Well, at least that's how it works for AArch64. - * Here we start with a guess that the addresses around 5/8th - * of the allowed space are unmapped and then work both down and - * up from there in 1/16th allowed space sized steps. - * - * Note, we need to use VA-bits - 1 when calculating the allowed - * virtual address space for an identity mapping because the upper - * half of the virtual address space is the two's complement of the - * lower and won't match physical addresses. - */ - bits = vm->va_bits - 1; - bits = vm->pa_bits < bits ? vm->pa_bits : bits; - end = 1ul << bits; - start = end * 5 / 8; - step = end / 16; - for (offset = 0; offset < end - start; offset += step) { - if (ucall_mmio_init(vm, start - offset)) - return; - if (ucall_mmio_init(vm, start + offset)) - return; - } - TEST_ASSERT(false, "Can't find a ucall mmio address"); - } -} - -void ucall_uninit(struct kvm_vm *vm) -{ - ucall_type = 0; - sync_global_to_guest(vm, ucall_type); - ucall_exit_mmio_addr = 0; - sync_global_to_guest(vm, ucall_exit_mmio_addr); -} - -static void ucall_pio_exit(struct ucall *uc) -{ -#ifdef __x86_64__ - asm volatile("in %[port], %%al" - : : [port] "d" (UCALL_PIO_PORT), "D" (uc) : "rax"); -#endif -} - -static void ucall_mmio_exit(struct ucall *uc) -{ - *ucall_exit_mmio_addr = (vm_vaddr_t)uc; -} - -void ucall(uint64_t cmd, int nargs, ...) -{ - struct ucall uc = { - .cmd = cmd, - }; - va_list va; - int i; - - nargs = nargs <= UCALL_MAX_ARGS ? nargs : UCALL_MAX_ARGS; - - va_start(va, nargs); - for (i = 0; i < nargs; ++i) - uc.args[i] = va_arg(va, uint64_t); - va_end(va); - - switch (ucall_type) { - case UCALL_PIO: - ucall_pio_exit(&uc); - break; - case UCALL_MMIO: - ucall_mmio_exit(&uc); - break; - }; -} - -uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc) -{ - struct kvm_run *run = vcpu_state(vm, vcpu_id); - struct ucall ucall = {}; - bool got_ucall = false; - -#ifdef __x86_64__ - if (ucall_type == UCALL_PIO && run->exit_reason == KVM_EXIT_IO && - run->io.port == UCALL_PIO_PORT) { - struct kvm_regs regs; - vcpu_regs_get(vm, vcpu_id, ®s); - memcpy(&ucall, addr_gva2hva(vm, (vm_vaddr_t)regs.rdi), sizeof(ucall)); - got_ucall = true; - } -#endif - if (ucall_type == UCALL_MMIO && run->exit_reason == KVM_EXIT_MMIO && - run->mmio.phys_addr == (uint64_t)ucall_exit_mmio_addr) { - vm_vaddr_t gva; - TEST_ASSERT(run->mmio.is_write && run->mmio.len == 8, - "Unexpected ucall exit mmio address access"); - memcpy(&gva, run->mmio.data, sizeof(gva)); - memcpy(&ucall, addr_gva2hva(vm, gva), sizeof(ucall)); - got_ucall = true; - } - - if (got_ucall) { - vcpu_run_complete_io(vm, vcpu_id); - if (uc) - memcpy(uc, &ucall, sizeof(ucall)); - } - - return ucall.cmd; -} |