// SPDX-License-Identifier: GPL-2.0-only
/*
 * KVM selftest s390x library code - CPU-related functions (page tables...)
 *
 * Copyright (C) 2019, Red Hat, Inc.
 */

#include "processor.h"
#include "kvm_util.h"

#define PAGES_PER_REGION 4

void virt_arch_pgd_alloc(struct kvm_vm *vm)
{
        vm_paddr_t paddr;

        TEST_ASSERT(vm->page_size == PAGE_SIZE, "Unsupported page size: 0x%x",
                    vm->page_size);

        if (vm->mmu.pgd_created)
                return;

        paddr = vm_phy_pages_alloc(vm, PAGES_PER_REGION,
                                   KVM_GUEST_PAGE_TABLE_MIN_PADDR,
                                   vm->memslots[MEM_REGION_PT]);
        memset(addr_gpa2hva(vm, paddr), 0xff, PAGES_PER_REGION * vm->page_size);

        vm->mmu.pgd = paddr;
        vm->mmu.pgd_created = true;
}

/*
 * Allocate 4 pages for a region/segment table (ri < 4), or one page for
 * a page table (ri == 4). Returns a suitable region/segment table entry
 * which points to the freshly allocated pages.
 */
static uint64_t virt_alloc_region(struct kvm_vm *vm, int ri)
{
        uint64_t taddr;

        taddr = vm_phy_pages_alloc(vm,  ri < 4 ? PAGES_PER_REGION : 1,
                                   KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
        memset(addr_gpa2hva(vm, taddr), 0xff, PAGES_PER_REGION * vm->page_size);

        return (taddr & REGION_ENTRY_ORIGIN)
                | (((4 - ri) << 2) & REGION_ENTRY_TYPE)
                | ((ri < 4 ? (PAGES_PER_REGION - 1) : 0) & REGION_ENTRY_LENGTH);
}

void virt_arch_pg_map(struct kvm_vm *vm, uint64_t gva, uint64_t gpa)
{
        int ri, idx;
        uint64_t *entry;

        TEST_ASSERT((gva % vm->page_size) == 0,
                "Virtual address not on page boundary,\n"
                "  vaddr: 0x%lx vm->page_size: 0x%x",
                gva, vm->page_size);
        TEST_ASSERT(sparsebit_is_set(vm->vpages_valid,
                (gva >> vm->page_shift)),
                "Invalid virtual address, vaddr: 0x%lx",
                gva);
        TEST_ASSERT((gpa % vm->page_size) == 0,
                "Physical address not on page boundary,\n"
                "  paddr: 0x%lx vm->page_size: 0x%x",
                gva, vm->page_size);
        TEST_ASSERT((gpa >> vm->page_shift) <= vm->max_gfn,
                "Physical address beyond beyond maximum supported,\n"
                "  paddr: 0x%lx vm->max_gfn: 0x%lx vm->page_size: 0x%x",
                gva, vm->max_gfn, vm->page_size);

        /* Walk through region and segment tables */
        entry = addr_gpa2hva(vm, vm->mmu.pgd);
        for (ri = 1; ri <= 4; ri++) {
                idx = (gva >> (64 - 11 * ri)) & 0x7ffu;
                if (entry[idx] & REGION_ENTRY_INVALID)
                        entry[idx] = virt_alloc_region(vm, ri);
                entry = addr_gpa2hva(vm, entry[idx] & REGION_ENTRY_ORIGIN);
        }

        /* Fill in page table entry */
        idx = (gva >> PAGE_SHIFT) & 0x0ffu;             /* page index */
        if (!(entry[idx] & PAGE_INVALID))
                fprintf(stderr,
                        "WARNING: PTE for gpa=0x%"PRIx64" already set!\n", gpa);
        entry[idx] = gpa;
}

vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
{
        int ri, idx;
        uint64_t *entry;

        TEST_ASSERT(vm->page_size == PAGE_SIZE, "Unsupported page size: 0x%x",
                    vm->page_size);

        entry = addr_gpa2hva(vm, vm->mmu.pgd);
        for (ri = 1; ri <= 4; ri++) {
                idx = (gva >> (64 - 11 * ri)) & 0x7ffu;
                TEST_ASSERT(!(entry[idx] & REGION_ENTRY_INVALID),
                            "No region mapping for vm virtual address 0x%lx",
                            gva);
                entry = addr_gpa2hva(vm, entry[idx] & REGION_ENTRY_ORIGIN);
        }

        idx = (gva >> PAGE_SHIFT) & 0x0ffu;             /* page index */

        TEST_ASSERT(!(entry[idx] & PAGE_INVALID),
                    "No page mapping for vm virtual address 0x%lx", gva);

        return (entry[idx] & ~0xffful) + (gva & 0xffful);
}

static void virt_dump_ptes(FILE *stream, struct kvm_vm *vm, uint8_t indent,
                           uint64_t ptea_start)
{
        uint64_t *pte, ptea;

        for (ptea = ptea_start; ptea < ptea_start + 0x100 * 8; ptea += 8) {
                pte = addr_gpa2hva(vm, ptea);
                if (*pte & PAGE_INVALID)
                        continue;
                fprintf(stream, "%*spte @ 0x%lx: 0x%016lx\n",
                        indent, "", ptea, *pte);
        }
}

static void virt_dump_region(FILE *stream, struct kvm_vm *vm, uint8_t indent,
                             uint64_t reg_tab_addr)
{
        uint64_t addr, *entry;

        for (addr = reg_tab_addr; addr < reg_tab_addr + 0x400 * 8; addr += 8) {
                entry = addr_gpa2hva(vm, addr);
                if (*entry & REGION_ENTRY_INVALID)
                        continue;
                fprintf(stream, "%*srt%lde @ 0x%lx: 0x%016lx\n",
                        indent, "", 4 - ((*entry & REGION_ENTRY_TYPE) >> 2),
                        addr, *entry);
                if (*entry & REGION_ENTRY_TYPE) {
                        virt_dump_region(stream, vm, indent + 2,
                                         *entry & REGION_ENTRY_ORIGIN);
                } else {
                        virt_dump_ptes(stream, vm, indent + 2,
                                       *entry & REGION_ENTRY_ORIGIN);
                }
        }
}

void virt_arch_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
{
        if (!vm->mmu.pgd_created)
                return;

        virt_dump_region(stream, vm, indent, vm->mmu.pgd);
}

void vcpu_arch_set_entry_point(struct kvm_vcpu *vcpu, void *guest_code)
{
        vcpu->run->psw_addr = (uintptr_t)guest_code;
}

struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id)
{
        size_t stack_size =  DEFAULT_STACK_PGS * getpagesize();
        uint64_t stack_vaddr;
        struct kvm_regs regs;
        struct kvm_sregs sregs;
        struct kvm_vcpu *vcpu;

        TEST_ASSERT(vm->page_size == PAGE_SIZE, "Unsupported page size: 0x%x",
                    vm->page_size);

        stack_vaddr = __vm_vaddr_alloc(vm, stack_size,
                                       DEFAULT_GUEST_STACK_VADDR_MIN,
                                       MEM_REGION_DATA);

        vcpu = __vm_vcpu_add(vm, vcpu_id);

        /* Setup guest registers */
        vcpu_regs_get(vcpu, &regs);
        regs.gprs[15] = stack_vaddr + (DEFAULT_STACK_PGS * getpagesize()) - 160;
        vcpu_regs_set(vcpu, &regs);

        vcpu_sregs_get(vcpu, &sregs);
        sregs.crs[0] |= 0x00040000;             /* Enable floating point regs */
        sregs.crs[1] = vm->mmu.pgd | 0xf;       /* Primary region table */
        vcpu_sregs_set(vcpu, &sregs);

        vcpu->run->psw_mask = 0x0400000180000000ULL;  /* DAT enabled + 64 bit mode */

        return vcpu;
}

void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
{
        va_list ap;
        struct kvm_regs regs;
        int i;

        TEST_ASSERT(num >= 1 && num <= 5, "Unsupported number of args,\n"
                    "  num: %u",
                    num);

        va_start(ap, num);
        vcpu_regs_get(vcpu, &regs);

        for (i = 0; i < num; i++)
                regs.gprs[i + 2] = va_arg(ap, uint64_t);

        vcpu_regs_set(vcpu, &regs);
        va_end(ap);
}

void vcpu_arch_dump(FILE *stream, struct kvm_vcpu *vcpu, uint8_t indent)
{
        fprintf(stream, "%*spstate: psw: 0x%.16llx:0x%.16llx\n",
                indent, "", vcpu->run->psw_mask, vcpu->run->psw_addr);
}

void assert_on_unhandled_exception(struct kvm_vcpu *vcpu)
{
}

bool kvm_arch_has_default_irqchip(void)
{
        return true;
}