mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-11-01 00:48:50 +00:00
a1f242ff46
This adds ioremap_prot and pte_pgprot() so that one can extract protection bits from a PTE and use them to ioremap_prot() (in order to support ptrace of VM_IO | VM_PFNMAP as per Rik's patch). This moves a couple of flag checks around in the ioremap implementations of arch/powerpc. There's a side effect of allowing non-cacheable and non-guarded mappings on ppc32 which before would always have _PAGE_GUARDED set whenever _PAGE_NO_CACHE is. (standard ioremap will still set _PAGE_GUARDED, but ioremap_prot will be capable of setting such a non guarded mapping). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Dave Airlie <airlied@linux.ie> Cc: Hugh Dickins <hugh@veritas.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
250 lines
6 KiB
C
250 lines
6 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/types.h>
|
|
#include <linux/mman.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/init.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/processor.h>
|
|
#include <asm/cputable.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/system.h>
|
|
#include <asm/abs_addr.h>
|
|
#include <asm/firmware.h>
|
|
|
|
#include "mmu_decl.h"
|
|
|
|
unsigned long ioremap_bot = IOREMAP_BASE;
|
|
|
|
/*
|
|
* map_io_page currently only called by __ioremap
|
|
* map_io_page adds an entry to the ioremap page table
|
|
* and adds an entry to the HPT, possibly bolting it
|
|
*/
|
|
static int map_io_page(unsigned long ea, unsigned long pa, int flags)
|
|
{
|
|
pgd_t *pgdp;
|
|
pud_t *pudp;
|
|
pmd_t *pmdp;
|
|
pte_t *ptep;
|
|
|
|
if (mem_init_done) {
|
|
pgdp = pgd_offset_k(ea);
|
|
pudp = pud_alloc(&init_mm, pgdp, ea);
|
|
if (!pudp)
|
|
return -ENOMEM;
|
|
pmdp = pmd_alloc(&init_mm, pudp, ea);
|
|
if (!pmdp)
|
|
return -ENOMEM;
|
|
ptep = pte_alloc_kernel(pmdp, ea);
|
|
if (!ptep)
|
|
return -ENOMEM;
|
|
set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT,
|
|
__pgprot(flags)));
|
|
} else {
|
|
/*
|
|
* If the mm subsystem is not fully up, we cannot create a
|
|
* linux page table entry for this mapping. Simply bolt an
|
|
* entry in the hardware page table.
|
|
*
|
|
*/
|
|
if (htab_bolt_mapping(ea, ea + PAGE_SIZE, pa, flags,
|
|
mmu_io_psize, mmu_kernel_ssize)) {
|
|
printk(KERN_ERR "Failed to do bolted mapping IO "
|
|
"memory at %016lx !\n", pa);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* __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);
|
|
|
|
/* Non-cacheable page cannot be coherent */
|
|
if (flags & _PAGE_NO_CACHE)
|
|
flags &= ~_PAGE_COHERENT;
|
|
|
|
/* We don't support the 4K PFN hack with ioremap */
|
|
if (flags & _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_io_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(phys_addr_t addr, unsigned long size,
|
|
unsigned long flags)
|
|
{
|
|
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 (mem_init_done) {
|
|
struct vm_struct *area;
|
|
|
|
area = __get_vm_area(size, VM_IOREMAP,
|
|
ioremap_bot, IOREMAP_END);
|
|
if (area == NULL)
|
|
return NULL;
|
|
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 = _PAGE_NO_CACHE | _PAGE_GUARDED;
|
|
|
|
if (ppc_md.ioremap)
|
|
return ppc_md.ioremap(addr, size, flags);
|
|
return __ioremap(addr, size, flags);
|
|
}
|
|
|
|
void __iomem * ioremap_flags(phys_addr_t addr, unsigned long size,
|
|
unsigned long flags)
|
|
{
|
|
/* writeable implies dirty for kernel addresses */
|
|
if (flags & _PAGE_RW)
|
|
flags |= _PAGE_DIRTY;
|
|
|
|
/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
|
|
flags &= ~(_PAGE_USER | _PAGE_EXEC);
|
|
|
|
if (ppc_md.ioremap)
|
|
return ppc_md.ioremap(addr, size, flags);
|
|
return __ioremap(addr, size, flags);
|
|
}
|
|
|
|
|
|
/*
|
|
* 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 (!mem_init_done)
|
|
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_flags);
|
|
EXPORT_SYMBOL(__ioremap);
|
|
EXPORT_SYMBOL(__ioremap_at);
|
|
EXPORT_SYMBOL(iounmap);
|
|
EXPORT_SYMBOL(__iounmap);
|
|
EXPORT_SYMBOL(__iounmap_at);
|