// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Page table handling routines for radix page table.
*
* Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation.
*/
#define pr_fmt(fmt) "radix-mmu: " fmt
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/sched/mm.h>
#include <linux/memblock.h>
#include <linux/of_fdt.h>
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/string_helpers.h>
#include <linux/memory.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <asm/dma.h>
#include <asm/machdep.h>
#include <asm/mmu.h>
#include <asm/firmware.h>
#include <asm/powernv.h>
#include <asm/sections.h>
#include <asm/smp.h>
#include <asm/trace.h>
#include <asm/uaccess.h>
#include <asm/ultravisor.h>
#include <trace/events/thp.h>
unsigned int mmu_pid_bits;
unsigned int mmu_base_pid;
unsigned int radix_mem_block_size __ro_after_init;
static __ref void *early_alloc_pgtable(unsigned long size, int nid,
unsigned long region_start, unsigned long region_end)
{
phys_addr_t min_addr = MEMBLOCK_LOW_LIMIT;
phys_addr_t max_addr = MEMBLOCK_ALLOC_ANYWHERE;
void *ptr;
if (region_start)
min_addr = region_start;
if (region_end)
max_addr = region_end;
ptr = memblock_alloc_try_nid(size, size, min_addr, max_addr, nid);
if (!ptr)
panic("%s: Failed to allocate %lu bytes align=0x%lx nid=%d from=%pa max_addr=%pa\n",
__func__, size, size, nid, &min_addr, &max_addr);
return ptr;
}
/*
* When allocating pud or pmd pointers, we allocate a complete page
* of PAGE_SIZE rather than PUD_TABLE_SIZE or PMD_TABLE_SIZE. This
* is to ensure that the page obtained from the memblock allocator
* can be completely used as page table page and can be freed
* correctly when the page table entries are removed.
*/
static int early_map_kernel_page(unsigned long ea, unsigned long pa,
pgprot_t flags,
unsigned int map_page_size,
int nid,
unsigned long region_start, unsigned long region_end)
{
unsigned long pfn = pa >> PAGE_SHIFT;
pgd_t *pgdp;
p4d_t *p4dp;
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
pgdp = pgd_offset_k(ea);
p4dp = p4d_offset(pgdp, ea);
if (p4d_none(*p4dp)) {
pudp = early_alloc_pgtable(PAGE_SIZE, nid,
region_start, region_end);
p4d_populate(&init_mm, p4dp, pudp);
}
pudp = pud_offset(p4dp, ea);
if (map_page_size == PUD_SIZE) {
ptep = (pte_t *)pudp;
goto set_the_pte;
}
if (pud_none(*pudp)) {
pmdp = early_alloc_pgtable<