alistair23-linux/arch/powerpc/mm/pgtable_64.c
Michael Ellerman 63ee9b2ff9 powerpc/mm/book3s64: Make KERN_IO_START a variable
Currently KERN_IO_START is defined as:

 #define KERN_IO_START  (KERN_VIRT_START + (KERN_VIRT_SIZE >> 1))

Although it looks like a constant, both the components are actually
variables, to allow us to have a different value between Radix and
Hash with a single kernel.

However that still requires both Radix and Hash to place the kernel IO
region at the same location relative to the start and end of the
kernel virtual region (namely 1/2 way through it), and we'd like to
change that.

So split KERN_IO_START out into its own variable, and initialise it
for Radix and Hash. In the medium term we should be able to
reconsolidate this, by doing a more involved rearrangement of the
location of the regions.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-08 19:37:04 +10:00

519 lines
13 KiB
C

/*
* This file contains ioremap and related functions for 64-bit machines.
*
* Derived from arch/ppc64/mm/init.c
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Modifications by Paul Mackerras (PowerMac) (paulus@samba.org)
* and Cort Dougan (PReP) (cort@cs.nmt.edu)
* Copyright (C) 1996 Paul Mackerras
*
* Derived from "arch/i386/mm/init.c"
* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
*
* Dave Engebretsen <engebret@us.ibm.com>
* Rework for PPC64 port.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/stddef.h>
#include <linux/vmalloc.h>
#include <linux/memblock.h>
#include <linux/slab.h>
#include <linux/hugetlb.h>
#include <asm/pgalloc.h>
#include <asm/page.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/smp.h>
#include <asm/machdep.h>
#include <asm/tlb.h>
#include <asm/trace.h>
#include <asm/processor.h>
#include <asm/cputable.h>
#include <asm/sections.h>
#include <asm/firmware.h>
#include <asm/dma.h>
#include <asm/powernv.h>
#include "mmu_decl.h"
#ifdef CONFIG_PPC_STD_MMU_64
#if TASK_SIZE_USER64 > (1UL << (ESID_BITS + SID_SHIFT))
#error TASK_SIZE_USER64 exceeds user VSID range
#endif
#endif
#ifdef CONFIG_PPC_BOOK3S_64
/*
* partition table and process table for ISA 3.0
*/
struct prtb_entry *process_tb;
struct patb_entry *partition_tb;
/*
* page table size
*/
unsigned long __pte_index_size;
EXPORT_SYMBOL(__pte_index_size);
unsigned long __pmd_index_size;
EXPORT_SYMBOL(__pmd_index_size);
unsigned long __pud_index_size;
EXPORT_SYMBOL(__pud_index_size);
unsigned long __pgd_index_size;
EXPORT_SYMBOL(__pgd_index_size);
unsigned long __pmd_cache_index;
EXPORT_SYMBOL(__pmd_cache_index);
unsigned long __pte_table_size;
EXPORT_SYMBOL(__pte_table_size);
unsigned long __pmd_table_size;
EXPORT_SYMBOL(__pmd_table_size);
unsigned long __pud_table_size;
EXPORT_SYMBOL(__pud_table_size);
unsigned long __pgd_table_size;
EXPORT_SYMBOL(__pgd_table_size);
unsigned long __pmd_val_bits;
EXPORT_SYMBOL(__pmd_val_bits);
unsigned long __pud_val_bits;
EXPORT_SYMBOL(__pud_val_bits);
unsigned long __pgd_val_bits;
EXPORT_SYMBOL(__pgd_val_bits);
unsigned long __kernel_virt_start;
EXPORT_SYMBOL(__kernel_virt_start);
unsigned long __kernel_virt_size;
EXPORT_SYMBOL(__kernel_virt_size);
unsigned long __vmalloc_start;
EXPORT_SYMBOL(__vmalloc_start);
unsigned long __vmalloc_end;
EXPORT_SYMBOL(__vmalloc_end);
unsigned long __kernel_io_start;
EXPORT_SYMBOL(__kernel_io_start);
struct page *vmemmap;
EXPORT_SYMBOL(vmemmap);
unsigned long __pte_frag_nr;
EXPORT_SYMBOL(__pte_frag_nr);
unsigned long __pte_frag_size_shift;
EXPORT_SYMBOL(__pte_frag_size_shift);
unsigned long ioremap_bot;
#else /* !CONFIG_PPC_BOOK3S_64 */
unsigned long ioremap_bot = IOREMAP_BASE;
#endif
/**
* __ioremap_at - Low level function to establish the page tables
* for an IO mapping
*/
void __iomem * __ioremap_at(phys_addr_t pa, void *ea, unsigned long size,
unsigned long flags)
{
unsigned long i;
/* Make sure we have the base flags */
if ((flags & _PAGE_PRESENT) == 0)
flags |= pgprot_val(PAGE_KERNEL);
/* We don't support the 4K PFN hack with ioremap */
if (flags & H_PAGE_4K_PFN)
return NULL;
WARN_ON(pa & ~PAGE_MASK);
WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
WARN_ON(size & ~PAGE_MASK);
for (i = 0; i < size; i += PAGE_SIZE)
if (map_kernel_page((unsigned long)ea+i, pa+i, flags))
return NULL;
return (void __iomem *)ea;
}
/**
* __iounmap_from - Low level function to tear down the page tables
* for an IO mapping. This is used for mappings that
* are manipulated manually, like partial unmapping of
* PCI IOs or ISA space.
*/
void __iounmap_at(void *ea, unsigned long size)
{
WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
WARN_ON(size & ~PAGE_MASK);
unmap_kernel_range((unsigned long)ea, size);
}
void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size,
unsigned long flags, void *caller)
{
phys_addr_t paligned;
void __iomem *ret;
/*
* Choose an address to map it to.
* Once the imalloc system is running, we use it.
* Before that, we map using addresses going
* up from ioremap_bot. imalloc will use
* the addresses from ioremap_bot through
* IMALLOC_END
*
*/
paligned = addr & PAGE_MASK;
size = PAGE_ALIGN(addr + size) - paligned;
if ((size == 0) || (paligned == 0))
return NULL;
if (slab_is_available()) {
struct vm_struct *area;
area = __get_vm_area_caller(size, VM_IOREMAP,
ioremap_bot, IOREMAP_END,
caller);
if (area == NULL)
return NULL;
area->phys_addr = paligned;
ret = __ioremap_at(paligned, area->addr, size, flags);
if (!ret)
vunmap(area->addr);
} else {
ret = __ioremap_at(paligned, (void *)ioremap_bot, size, flags);
if (ret)
ioremap_bot += size;
}
if (ret)
ret += addr & ~PAGE_MASK;
return ret;
}
void __iomem * __ioremap(phys_addr_t addr, unsigned long size,
unsigned long flags)
{
return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
}
void __iomem * ioremap(phys_addr_t addr, unsigned long size)
{
unsigned long flags = pgprot_val(pgprot_noncached(__pgprot(0)));
void *caller = __builtin_return_address(0);
if (ppc_md.ioremap)
return ppc_md.ioremap(addr, size, flags, caller);
return __ioremap_caller(addr, size, flags, caller);
}
void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size)
{
unsigned long flags = pgprot_val(pgprot_noncached_wc(__pgprot(0)));
void *caller = __builtin_return_address(0);
if (ppc_md.ioremap)
return ppc_md.ioremap(addr, size, flags, caller);
return __ioremap_caller(addr, size, flags, caller);
}
void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size,
unsigned long flags)
{
void *caller = __builtin_return_address(0);
/* writeable implies dirty for kernel addresses */
if (flags & _PAGE_WRITE)
flags |= _PAGE_DIRTY;
/* we don't want to let _PAGE_EXEC leak out */
flags &= ~_PAGE_EXEC;
/*
* Force kernel mapping.
*/
#if defined(CONFIG_PPC_BOOK3S_64)
flags |= _PAGE_PRIVILEGED;
#else
flags &= ~_PAGE_USER;
#endif
#ifdef _PAGE_BAP_SR
/* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
* which means that we just cleared supervisor access... oops ;-) This
* restores it
*/
flags |= _PAGE_BAP_SR;
#endif
if (ppc_md.ioremap)
return ppc_md.ioremap(addr, size, flags, caller);
return __ioremap_caller(addr, size, flags, caller);
}
/*
* Unmap an IO region and remove it from imalloc'd list.
* Access to IO memory should be serialized by driver.
*/
void __iounmap(volatile void __iomem *token)
{
void *addr;
if (!slab_is_available())
return;
addr = (void *) ((unsigned long __force)
PCI_FIX_ADDR(token) & PAGE_MASK);
if ((unsigned long)addr < ioremap_bot) {
printk(KERN_WARNING "Attempt to iounmap early bolted mapping"
" at 0x%p\n", addr);
return;
}
vunmap(addr);
}
void iounmap(volatile void __iomem *token)
{
if (ppc_md.iounmap)
ppc_md.iounmap(token);
else
__iounmap(token);
}
EXPORT_SYMBOL(ioremap);
EXPORT_SYMBOL(ioremap_wc);
EXPORT_SYMBOL(ioremap_prot);
EXPORT_SYMBOL(__ioremap);
EXPORT_SYMBOL(__ioremap_at);
EXPORT_SYMBOL(iounmap);
EXPORT_SYMBOL(__iounmap);
EXPORT_SYMBOL(__iounmap_at);
#ifndef __PAGETABLE_PUD_FOLDED
/* 4 level page table */
struct page *pgd_page(pgd_t pgd)
{
if (pgd_huge(pgd))
return pte_page(pgd_pte(pgd));
return virt_to_page(pgd_page_vaddr(pgd));
}
#endif
struct page *pud_page(pud_t pud)
{
if (pud_huge(pud))
return pte_page(pud_pte(pud));
return virt_to_page(pud_page_vaddr(pud));
}
/*
* For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags
* For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address.
*/
struct page *pmd_page(pmd_t pmd)
{
if (pmd_trans_huge(pmd) || pmd_huge(pmd) || pmd_devmap(pmd))
return pte_page(pmd_pte(pmd));
return virt_to_page(pmd_page_vaddr(pmd));
}
#ifdef CONFIG_PPC_64K_PAGES
static pte_t *get_from_cache(struct mm_struct *mm)
{
void *pte_frag, *ret;
spin_lock(&mm->page_table_lock);
ret = mm->context.pte_frag;
if (ret) {
pte_frag = ret + PTE_FRAG_SIZE;
/*
* If we have taken up all the fragments mark PTE page NULL
*/
if (((unsigned long)pte_frag & ~PAGE_MASK) == 0)
pte_frag = NULL;
mm->context.pte_frag = pte_frag;
}
spin_unlock(&mm->page_table_lock);
return (pte_t *)ret;
}
static pte_t *__alloc_for_cache(struct mm_struct *mm, int kernel)
{
void *ret = NULL;
struct page *page;
if (!kernel) {
page = alloc_page(PGALLOC_GFP | __GFP_ACCOUNT);
if (!page)
return NULL;
if (!pgtable_page_ctor(page)) {
__free_page(page);
return NULL;
}
} else {
page = alloc_page(PGALLOC_GFP);
if (!page)
return NULL;
}
ret = page_address(page);
spin_lock(&mm->page_table_lock);
/*
* If we find pgtable_page set, we return
* the allocated page with single fragement
* count.
*/
if (likely(!mm->context.pte_frag)) {
set_page_count(page, PTE_FRAG_NR);
mm->context.pte_frag = ret + PTE_FRAG_SIZE;
}
spin_unlock(&mm->page_table_lock);
return (pte_t *)ret;
}
pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel)
{
pte_t *pte;
pte = get_from_cache(mm);
if (pte)
return pte;
return __alloc_for_cache(mm, kernel);
}
#endif /* CONFIG_PPC_64K_PAGES */
void pte_fragment_free(unsigned long *table, int kernel)
{
struct page *page = virt_to_page(table);
if (put_page_testzero(page)) {
if (!kernel)
pgtable_page_dtor(page);
free_hot_cold_page(page, 0);
}
}
#ifdef CONFIG_SMP
void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift)
{
unsigned long pgf = (unsigned long)table;
BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
pgf |= shift;
tlb_remove_table(tlb, (void *)pgf);
}
void __tlb_remove_table(void *_table)
{
void *table = (void *)((unsigned long)_table & ~MAX_PGTABLE_INDEX_SIZE);
unsigned shift = (unsigned long)_table & MAX_PGTABLE_INDEX_SIZE;
if (!shift)
/* PTE page needs special handling */
pte_fragment_free(table, 0);
else {
BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
kmem_cache_free(PGT_CACHE(shift), table);
}
}
#else
void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift)
{
if (!shift) {
/* PTE page needs special handling */
pte_fragment_free(table, 0);
} else {
BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
kmem_cache_free(PGT_CACHE(shift), table);
}
}
#endif
#ifdef CONFIG_PPC_BOOK3S_64
void __init mmu_partition_table_init(void)
{
unsigned long patb_size = 1UL << PATB_SIZE_SHIFT;
unsigned long ptcr;
BUILD_BUG_ON_MSG((PATB_SIZE_SHIFT > 36), "Partition table size too large.");
partition_tb = __va(memblock_alloc_base(patb_size, patb_size,
MEMBLOCK_ALLOC_ANYWHERE));
/* Initialize the Partition Table with no entries */
memset((void *)partition_tb, 0, patb_size);
/*
* update partition table control register,
* 64 K size.
*/
ptcr = __pa(partition_tb) | (PATB_SIZE_SHIFT - 12);
mtspr(SPRN_PTCR, ptcr);
powernv_set_nmmu_ptcr(ptcr);
}
void mmu_partition_table_set_entry(unsigned int lpid, unsigned long dw0,
unsigned long dw1)
{
unsigned long old = be64_to_cpu(partition_tb[lpid].patb0);
partition_tb[lpid].patb0 = cpu_to_be64(dw0);
partition_tb[lpid].patb1 = cpu_to_be64(dw1);
/*
* Global flush of TLBs and partition table caches for this lpid.
* The type of flush (hash or radix) depends on what the previous
* use of this partition ID was, not the new use.
*/
asm volatile("ptesync" : : : "memory");
if (old & PATB_HR) {
asm volatile(PPC_TLBIE_5(%0,%1,2,0,1) : :
"r" (TLBIEL_INVAL_SET_LPID), "r" (lpid));
trace_tlbie(lpid, 0, TLBIEL_INVAL_SET_LPID, lpid, 2, 0, 1);
} else {
asm volatile(PPC_TLBIE_5(%0,%1,2,0,0) : :
"r" (TLBIEL_INVAL_SET_LPID), "r" (lpid));
trace_tlbie(lpid, 0, TLBIEL_INVAL_SET_LPID, lpid, 2, 0, 0);
}
asm volatile("eieio; tlbsync; ptesync" : : : "memory");
}
EXPORT_SYMBOL_GPL(mmu_partition_table_set_entry);
#endif /* CONFIG_PPC_BOOK3S_64 */
#ifdef CONFIG_STRICT_KERNEL_RWX
void mark_rodata_ro(void)
{
if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) {
pr_warn("Warning: Unable to mark rodata read only on this CPU.\n");
return;
}
if (radix_enabled())
radix__mark_rodata_ro();
else
hash__mark_rodata_ro();
}
void mark_initmem_nx(void)
{
if (radix_enabled())
radix__mark_initmem_nx();
else
hash__mark_initmem_nx();
}
#endif