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mmu.c
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mmu.c
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// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/mm/mmu.c
*
* Copyright (C) 1995-2005 Russell King
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/memblock.h>
#include <linux/fs.h>
#include <linux/vmalloc.h>
#include <linux/sizes.h>
#include <asm/cp15.h>
#include <asm/cputype.h>
#include <asm/cachetype.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp_plat.h>
#include <asm/tlb.h>
#include <asm/highmem.h>
#include <asm/system_info.h>
#include <asm/traps.h>
#include <asm/procinfo.h>
#include <asm/memory.h>
#include <asm/pgalloc.h>
#include <asm/kasan_def.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <asm/mach/pci.h>
#include <asm/fixmap.h>
#include "fault.h"
#include "mm.h"
#include "tcm.h"
extern unsigned long __atags_pointer;
/*
* empty_zero_page is a special page that is used for
* zero-initialized data and COW.
*/
struct page *empty_zero_page;
EXPORT_SYMBOL(empty_zero_page);
/*
* The pmd table for the upper-most set of pages.
*/
pmd_t *top_pmd;
pmdval_t user_pmd_table = _PAGE_USER_TABLE;
#define CPOLICY_UNCACHED 0
#define CPOLICY_BUFFERED 1
#define CPOLICY_WRITETHROUGH 2
#define CPOLICY_WRITEBACK 3
#define CPOLICY_WRITEALLOC 4
static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
static unsigned int ecc_mask __initdata = 0;
pgprot_t pgprot_user;
pgprot_t pgprot_kernel;
EXPORT_SYMBOL(pgprot_user);
EXPORT_SYMBOL(pgprot_kernel);
struct cachepolicy {
const char policy[16];
unsigned int cr_mask;
pmdval_t pmd;
pteval_t pte;
};
static struct cachepolicy cache_policies[] __initdata = {
{
.policy = "uncached",
.cr_mask = CR_W|CR_C,
.pmd = PMD_SECT_UNCACHED,
.pte = L_PTE_MT_UNCACHED,
}, {
.policy = "buffered",
.cr_mask = CR_C,
.pmd = PMD_SECT_BUFFERED,
.pte = L_PTE_MT_BUFFERABLE,
}, {
.policy = "writethrough",
.cr_mask = 0,
.pmd = PMD_SECT_WT,
.pte = L_PTE_MT_WRITETHROUGH,
}, {
.policy = "writeback",
.cr_mask = 0,
.pmd = PMD_SECT_WB,
.pte = L_PTE_MT_WRITEBACK,
}, {
.policy = "writealloc",
.cr_mask = 0,
.pmd = PMD_SECT_WBWA,
.pte = L_PTE_MT_WRITEALLOC,
}
};
#ifdef CONFIG_CPU_CP15
static unsigned long initial_pmd_value __initdata = 0;
/*
* Initialise the cache_policy variable with the initial state specified
* via the "pmd" value. This is used to ensure that on ARMv6 and later,
* the C code sets the page tables up with the same policy as the head
* assembly code, which avoids an illegal state where the TLBs can get
* confused. See comments in early_cachepolicy() for more information.
*/
void __init init_default_cache_policy(unsigned long pmd)
{
int i;
initial_pmd_value = pmd;
pmd &= PMD_SECT_CACHE_MASK;
for (i = 0; i < ARRAY_SIZE(cache_policies); i++)
if (cache_policies[i].pmd == pmd) {
cachepolicy = i;
break;
}
if (i == ARRAY_SIZE(cache_policies))
pr_err("ERROR: could not find cache policy\n");
}
/*
* These are useful for identifying cache coherency problems by allowing
* the cache or the cache and writebuffer to be turned off. (Note: the
* write buffer should not be on and the cache off).
*/
static int __init early_cachepolicy(char *p)
{
int i, selected = -1;
for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
int len = strlen(cache_policies[i].policy);
if (memcmp(p, cache_policies[i].policy, len) == 0) {
selected = i;
break;
}
}
if (selected == -1)
pr_err("ERROR: unknown or unsupported cache policy\n");
/*
* This restriction is partly to do with the way we boot; it is
* unpredictable to have memory mapped using two different sets of
* memory attributes (shared, type, and cache attribs). We can not
* change these attributes once the initial assembly has setup the
* page tables.
*/
if (cpu_architecture() >= CPU_ARCH_ARMv6 && selected != cachepolicy) {
pr_warn("Only cachepolicy=%s supported on ARMv6 and later\n",
cache_policies[cachepolicy].policy);
return 0;
}
if (selected != cachepolicy) {
unsigned long cr = __clear_cr(cache_policies[selected].cr_mask);
cachepolicy = selected;
flush_cache_all();
set_cr(cr);
}
return 0;
}
early_param("cachepolicy", early_cachepolicy);
static int __init early_nocache(char *__unused)
{
char *p = "buffered";
pr_warn("nocache is deprecated; use cachepolicy=%s\n", p);
early_cachepolicy(p);
return 0;
}
early_param("nocache", early_nocache);
static int __init early_nowrite(char *__unused)
{
char *p = "uncached";
pr_warn("nowb is deprecated; use cachepolicy=%s\n", p);
early_cachepolicy(p);
return 0;
}
early_param("nowb", early_nowrite);
#ifndef CONFIG_ARM_LPAE
static int __init early_ecc(char *p)
{
if (memcmp(p, "on", 2) == 0)
ecc_mask = PMD_PROTECTION;
else if (memcmp(p, "off", 3) == 0)
ecc_mask = 0;
return 0;
}
early_param("ecc", early_ecc);
#endif
#else /* ifdef CONFIG_CPU_CP15 */
static int __init early_cachepolicy(char *p)
{
pr_warn("cachepolicy kernel parameter not supported without cp15\n");
return 0;
}
early_param("cachepolicy", early_cachepolicy);
static int __init noalign_setup(char *__unused)
{
pr_warn("noalign kernel parameter not supported without cp15\n");
return 1;
}
__setup("noalign", noalign_setup);
#endif /* ifdef CONFIG_CPU_CP15 / else */
#define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN
#define PROT_PTE_S2_DEVICE PROT_PTE_DEVICE
#define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_AP_WRITE
static struct mem_type mem_types[] __ro_after_init = {
[MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
.prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
L_PTE_SHARED,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PROT_SECT_DEVICE | PMD_SECT_S,
.domain = DOMAIN_IO,
},
[MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
.prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PROT_SECT_DEVICE,
.domain = DOMAIN_IO,
},
[MT_DEVICE_CACHED] = { /* ioremap_cache */
.prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
.domain = DOMAIN_IO,
},
[MT_DEVICE_WC] = { /* ioremap_wc */
.prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PROT_SECT_DEVICE,
.domain = DOMAIN_IO,
},
[MT_UNCACHED] = {
.prot_pte = PROT_PTE_DEVICE,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
.domain = DOMAIN_IO,
},
[MT_CACHECLEAN] = {
.prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
.domain = DOMAIN_KERNEL,
},
#ifndef CONFIG_ARM_LPAE
[MT_MINICLEAN] = {
.prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
.domain = DOMAIN_KERNEL,
},
#endif
[MT_LOW_VECTORS] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_RDONLY,
.prot_l1 = PMD_TYPE_TABLE,
.domain = DOMAIN_VECTORS,
},
[MT_HIGH_VECTORS] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_USER | L_PTE_RDONLY,
.prot_l1 = PMD_TYPE_TABLE,
.domain = DOMAIN_VECTORS,
},
[MT_MEMORY_RWX] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
.domain = DOMAIN_KERNEL,
},
[MT_MEMORY_RW] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_XN,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
.domain = DOMAIN_KERNEL,
},
[MT_ROM] = {
.prot_sect = PMD_TYPE_SECT,
.domain = DOMAIN_KERNEL,
},
[MT_MEMORY_RWX_NONCACHED] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_MT_BUFFERABLE,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
.domain = DOMAIN_KERNEL,
},
[MT_MEMORY_RW_DTCM] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_XN,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
.domain = DOMAIN_KERNEL,
},
[MT_MEMORY_RWX_ITCM] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
.prot_l1 = PMD_TYPE_TABLE,
.domain = DOMAIN_KERNEL,
},
[MT_MEMORY_RW_SO] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_MT_UNCACHED | L_PTE_XN,
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_S |
PMD_SECT_UNCACHED | PMD_SECT_XN,
.domain = DOMAIN_KERNEL,
},
[MT_MEMORY_DMA_READY] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_XN,
.prot_l1 = PMD_TYPE_TABLE,
.domain = DOMAIN_KERNEL,
},
};
const struct mem_type *get_mem_type(unsigned int type)
{
return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
}
EXPORT_SYMBOL(get_mem_type);
static pte_t *(*pte_offset_fixmap)(pmd_t *dir, unsigned long addr);
static pte_t bm_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
__aligned(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE) __initdata;
static pte_t * __init pte_offset_early_fixmap(pmd_t *dir, unsigned long addr)
{
return &bm_pte[pte_index(addr)];
}
static pte_t *pte_offset_late_fixmap(pmd_t *dir, unsigned long addr)
{
return pte_offset_kernel(dir, addr);
}
static inline pmd_t * __init fixmap_pmd(unsigned long addr)
{
return pmd_off_k(addr);
}
void __init early_fixmap_init(void)
{
pmd_t *pmd;
/*
* The early fixmap range spans multiple pmds, for which
* we are not prepared:
*/
BUILD_BUG_ON((__fix_to_virt(__end_of_early_ioremap_region) >> PMD_SHIFT)
!= FIXADDR_TOP >> PMD_SHIFT);
pmd = fixmap_pmd(FIXADDR_TOP);
pmd_populate_kernel(&init_mm, pmd, bm_pte);
pte_offset_fixmap = pte_offset_early_fixmap;
}
/*
* To avoid TLB flush broadcasts, this uses local_flush_tlb_kernel_range().
* As a result, this can only be called with preemption disabled, as under
* stop_machine().
*/
void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
{
unsigned long vaddr = __fix_to_virt(idx);
pte_t *pte = pte_offset_fixmap(pmd_off_k(vaddr), vaddr);
/* Make sure fixmap region does not exceed available allocation. */
BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) < FIXADDR_START);
BUG_ON(idx >= __end_of_fixed_addresses);
/* We support only device mappings before pgprot_kernel is set. */
if (WARN_ON(pgprot_val(prot) != pgprot_val(FIXMAP_PAGE_IO) &&
pgprot_val(prot) && pgprot_val(pgprot_kernel) == 0))
return;
if (pgprot_val(prot))
set_pte_at(NULL, vaddr, pte,
pfn_pte(phys >> PAGE_SHIFT, prot));
else
pte_clear(NULL, vaddr, pte);
local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
}
/*
* Adjust the PMD section entries according to the CPU in use.
*/
static void __init build_mem_type_table(void)
{
struct cachepolicy *cp;
unsigned int cr = get_cr();
pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
int cpu_arch = cpu_architecture();
int i;
if (cpu_arch < CPU_ARCH_ARMv6) {
#if defined(CONFIG_CPU_DCACHE_DISABLE)
if (cachepolicy > CPOLICY_BUFFERED)
cachepolicy = CPOLICY_BUFFERED;
#elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
if (cachepolicy > CPOLICY_WRITETHROUGH)
cachepolicy = CPOLICY_WRITETHROUGH;
#endif
}
if (cpu_arch < CPU_ARCH_ARMv5) {
if (cachepolicy >= CPOLICY_WRITEALLOC)
cachepolicy = CPOLICY_WRITEBACK;
ecc_mask = 0;
}
if (is_smp()) {
if (cachepolicy != CPOLICY_WRITEALLOC) {
pr_warn("Forcing write-allocate cache policy for SMP\n");
cachepolicy = CPOLICY_WRITEALLOC;
}
if (!(initial_pmd_value & PMD_SECT_S)) {
pr_warn("Forcing shared mappings for SMP\n");
initial_pmd_value |= PMD_SECT_S;
}
}
/*
* Strip out features not present on earlier architectures.
* Pre-ARMv5 CPUs don't have TEX bits. Pre-ARMv6 CPUs or those
* without extended page tables don't have the 'Shared' bit.
*/
if (cpu_arch < CPU_ARCH_ARMv5)
for (i = 0; i < ARRAY_SIZE(mem_types); i++)
mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
for (i = 0; i < ARRAY_SIZE(mem_types); i++)
mem_types[i].prot_sect &= ~PMD_SECT_S;
/*
* ARMv5 and lower, bit 4 must be set for page tables (was: cache
* "update-able on write" bit on ARM610). However, Xscale and
* Xscale3 require this bit to be cleared.
*/
if (cpu_is_xscale_family()) {
for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
mem_types[i].prot_sect &= ~PMD_BIT4;
mem_types[i].prot_l1 &= ~PMD_BIT4;
}
} else if (cpu_arch < CPU_ARCH_ARMv6) {
for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
if (mem_types[i].prot_l1)
mem_types[i].prot_l1 |= PMD_BIT4;
if (mem_types[i].prot_sect)
mem_types[i].prot_sect |= PMD_BIT4;
}
}
/*
* Mark the device areas according to the CPU/architecture.
*/
if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
if (!cpu_is_xsc3()) {
/*
* Mark device regions on ARMv6+ as execute-never
* to prevent speculative instruction fetches.
*/
mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
/* Also setup NX memory mapping */
mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_XN;
}
if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
/*
* For ARMv7 with TEX remapping,
* - shared device is SXCB=1100
* - nonshared device is SXCB=0100
* - write combine device mem is SXCB=0001
* (Uncached Normal memory)
*/
mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(1);
mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
} else if (cpu_is_xsc3()) {
/*
* For Xscale3,
* - shared device is TEXCB=00101
* - nonshared device is TEXCB=01000
* - write combine device mem is TEXCB=00100
* (Inner/Outer Uncacheable in xsc3 parlance)
*/
mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1) | PMD_SECT_BUFFERED;
mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
} else {
/*
* For ARMv6 and ARMv7 without TEX remapping,
* - shared device is TEXCB=00001
* - nonshared device is TEXCB=01000
* - write combine device mem is TEXCB=00100
* (Uncached Normal in ARMv6 parlance).
*/
mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
}
} else {
/*
* On others, write combining is "Uncached/Buffered"
*/
mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
}
/*
* Now deal with the memory-type mappings
*/
cp = &cache_policies[cachepolicy];
vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
#ifndef CONFIG_ARM_LPAE
/*
* We don't use domains on ARMv6 (since this causes problems with
* v6/v7 kernels), so we must use a separate memory type for user
* r/o, kernel r/w to map the vectors page.
*/
if (cpu_arch == CPU_ARCH_ARMv6)
vecs_pgprot |= L_PTE_MT_VECTORS;
/*
* Check is it with support for the PXN bit
* in the Short-descriptor translation table format descriptors.
*/
if (cpu_arch == CPU_ARCH_ARMv7 &&
(read_cpuid_ext(CPUID_EXT_MMFR0) & 0xF) >= 4) {
user_pmd_table |= PMD_PXNTABLE;
}
#endif
/*
* ARMv6 and above have extended page tables.
*/
if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
#ifndef CONFIG_ARM_LPAE
/*
* Mark cache clean areas and XIP ROM read only
* from SVC mode and no access from userspace.
*/
mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
#endif
/*
* If the initial page tables were created with the S bit
* set, then we need to do the same here for the same
* reasons given in early_cachepolicy().
*/
if (initial_pmd_value & PMD_SECT_S) {
user_pgprot |= L_PTE_SHARED;
kern_pgprot |= L_PTE_SHARED;
vecs_pgprot |= L_PTE_SHARED;
mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_RWX].prot_sect |= PMD_SECT_S;
mem_types[MT_MEMORY_RWX].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_S;
mem_types[MT_MEMORY_RW].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_S;
mem_types[MT_MEMORY_RWX_NONCACHED].prot_pte |= L_PTE_SHARED;
}
}
/*
* Non-cacheable Normal - intended for memory areas that must
* not cause dirty cache line writebacks when used
*/
if (cpu_arch >= CPU_ARCH_ARMv6) {
if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
/* Non-cacheable Normal is XCB = 001 */
mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
PMD_SECT_BUFFERED;
} else {
/* For both ARMv6 and non-TEX-remapping ARMv7 */
mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
PMD_SECT_TEX(1);
}
} else {
mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
}
#ifdef CONFIG_ARM_LPAE
/*
* Do not generate access flag faults for the kernel mappings.
*/
for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
mem_types[i].prot_pte |= PTE_EXT_AF;
if (mem_types[i].prot_sect)
mem_types[i].prot_sect |= PMD_SECT_AF;
}
kern_pgprot |= PTE_EXT_AF;
vecs_pgprot |= PTE_EXT_AF;
/*
* Set PXN for user mappings
*/
user_pgprot |= PTE_EXT_PXN;
#endif
for (i = 0; i < 16; i++) {
pteval_t v = pgprot_val(protection_map[i]);
protection_map[i] = __pgprot(v | user_pgprot);
}
mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
L_PTE_DIRTY | kern_pgprot);
mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
mem_types[MT_MEMORY_RWX].prot_sect |= ecc_mask | cp->pmd;
mem_types[MT_MEMORY_RWX].prot_pte |= kern_pgprot;
mem_types[MT_MEMORY_RW].prot_sect |= ecc_mask | cp->pmd;
mem_types[MT_MEMORY_RW].prot_pte |= kern_pgprot;
mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= ecc_mask;
mem_types[MT_ROM].prot_sect |= cp->pmd;
switch (cp->pmd) {
case PMD_SECT_WT:
mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
break;
case PMD_SECT_WB:
case PMD_SECT_WBWA:
mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
break;
}
pr_info("Memory policy: %sData cache %s\n",
ecc_mask ? "ECC enabled, " : "", cp->policy);
for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
struct mem_type *t = &mem_types[i];
if (t->prot_l1)
t->prot_l1 |= PMD_DOMAIN(t->domain);
if (t->prot_sect)
t->prot_sect |= PMD_DOMAIN(t->domain);
}
}
#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
if (!pfn_valid(pfn))
return pgprot_noncached(vma_prot);
else if (file->f_flags & O_SYNC)
return pgprot_writecombine(vma_prot);
return vma_prot;
}
EXPORT_SYMBOL(phys_mem_access_prot);
#endif
#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
static void __init *early_alloc(unsigned long sz)
{
void *ptr = memblock_alloc(sz, sz);
if (!ptr)
panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
__func__, sz, sz);
return ptr;
}
static void *__init late_alloc(unsigned long sz)
{
void *ptr = (void *)__get_free_pages(GFP_PGTABLE_KERNEL, get_order(sz));
if (!ptr || !pgtable_pte_page_ctor(virt_to_page(ptr)))
BUG();
return ptr;
}
static pte_t * __init arm_pte_alloc(pmd_t *pmd, unsigned long addr,
unsigned long prot,
void *(*alloc)(unsigned long sz))
{
if (pmd_none(*pmd)) {
pte_t *pte = alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
__pmd_populate(pmd, __pa(pte), prot);
}
BUG_ON(pmd_bad(*pmd));
return pte_offset_kernel(pmd, addr);
}
static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,
unsigned long prot)
{
return arm_pte_alloc(pmd, addr, prot, early_alloc);
}
static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
unsigned long end, unsigned long pfn,
const struct mem_type *type,
void *(*alloc)(unsigned long sz),
bool ng)
{
pte_t *pte = arm_pte_alloc(pmd, addr, type->prot_l1, alloc);
do {
set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)),
ng ? PTE_EXT_NG : 0);
pfn++;
} while (pte++, addr += PAGE_SIZE, addr != end);
}
static void __init __map_init_section(pmd_t *pmd, unsigned long addr,
unsigned long end, phys_addr_t phys,
const struct mem_type *type, bool ng)
{
pmd_t *p = pmd;
#ifndef CONFIG_ARM_LPAE
/*
* In classic MMU format, puds and pmds are folded in to
* the pgds. pmd_offset gives the PGD entry. PGDs refer to a
* group of L1 entries making up one logical pointer to
* an L2 table (2MB), where as PMDs refer to the individual
* L1 entries (1MB). Hence increment to get the correct
* offset for odd 1MB sections.
* (See arch/arm/include/asm/pgtable-2level.h)
*/
if (addr & SECTION_SIZE)
pmd++;
#endif
do {
*pmd = __pmd(phys | type->prot_sect | (ng ? PMD_SECT_nG : 0));
phys += SECTION_SIZE;
} while (pmd++, addr += SECTION_SIZE, addr != end);
flush_pmd_entry(p);
}
static void __init alloc_init_pmd(pud_t *pud, unsigned long addr,
unsigned long end, phys_addr_t phys,
const struct mem_type *type,
void *(*alloc)(unsigned long sz), bool ng)
{
pmd_t *pmd = pmd_offset(pud, addr);
unsigned long next;
do {
/*
* With LPAE, we must loop over to map
* all the pmds for the given range.
*/
next = pmd_addr_end(addr, end);
/*
* Try a section mapping - addr, next and phys must all be
* aligned to a section boundary.
*/
if (type->prot_sect &&
((addr | next | phys) & ~SECTION_MASK) == 0) {
__map_init_section(pmd, addr, next, phys, type, ng);
} else {
alloc_init_pte(pmd, addr, next,
__phys_to_pfn(phys), type, alloc, ng);
}
phys += next - addr;
} while (pmd++, addr = next, addr != end);
}
static void __init alloc_init_pud(p4d_t *p4d, unsigned long addr,
unsigned long end, phys_addr_t phys,
const struct mem_type *type,
void *(*alloc)(unsigned long sz), bool ng)
{
pud_t *pud = pud_offset(p4d, addr);
unsigned long next;
do {
next = pud_addr_end(addr, end);
alloc_init_pmd(pud, addr, next, phys, type, alloc, ng);
phys += next - addr;
} while (pud++, addr = next, addr != end);
}
static void __init alloc_init_p4d(pgd_t *pgd, unsigned long addr,
unsigned long end, phys_addr_t phys,
const struct mem_type *type,
void *(*alloc)(unsigned long sz), bool ng)
{
p4d_t *p4d = p4d_offset(pgd, addr);
unsigned long next;
do {
next = p4d_addr_end(addr, end);
alloc_init_pud(p4d, addr, next, phys, type, alloc, ng);
phys += next - addr;
} while (p4d++, addr = next, addr != end);
}
#ifndef CONFIG_ARM_LPAE
static void __init create_36bit_mapping(struct mm_struct *mm,
struct map_desc *md,
const struct mem_type *type,
bool ng)
{
unsigned long addr, length, end;
phys_addr_t phys;
pgd_t *pgd;
addr = md->virtual;
phys = __pfn_to_phys(md->pfn);
length = PAGE_ALIGN(md->length);
if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
pr_err("MM: CPU does not support supersection mapping for 0x%08llx at 0x%08lx\n",
(long long)__pfn_to_phys((u64)md->pfn), addr);
return;
}
/* N.B. ARMv6 supersections are only defined to work with domain 0.
* Since domain assignments can in fact be arbitrary, the
* 'domain == 0' check below is required to insure that ARMv6
* supersections are only allocated for domain 0 regardless
* of the actual domain assignments in use.
*/
if (type->domain) {
pr_err("MM: invalid domain in supersection mapping for 0x%08llx at 0x%08lx\n",
(long long)__pfn_to_phys((u64)md->pfn), addr);
return;
}
if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
pr_err("MM: cannot create mapping for 0x%08llx at 0x%08lx invalid alignment\n",
(long long)__pfn_to_phys((u64)md->pfn), addr);
return;
}
/*
* Shift bits [35:32] of address into bits [23:20] of PMD
* (See ARMv6 spec).
*/
phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
pgd = pgd_offset(mm, addr);
end = addr + length;
do {
p4d_t *p4d = p4d_offset(pgd, addr);
pud_t *pud = pud_offset(p4d, addr);
pmd_t *pmd = pmd_offset(pud, addr);
int i;
for (i = 0; i < 16; i++)
*pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER |
(ng ? PMD_SECT_nG : 0));
addr += SUPERSECTION_SIZE;
phys += SUPERSECTION_SIZE;
pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
} while (addr != end);
}
#endif /* !CONFIG_ARM_LPAE */
static void __init __create_mapping(struct mm_struct *mm, struct map_desc *md,
void *(*alloc)(unsigned long sz),
bool ng)
{
unsigned long addr, length, end;
phys_addr_t phys;
const struct mem_type *type;
pgd_t *pgd;
type = &mem_types[md->type];
#ifndef CONFIG_ARM_LPAE
/*
* Catch 36-bit addresses
*/
if (md->pfn >= 0x100000) {
create_36bit_mapping(mm, md, type, ng);
return;
}
#endif
addr = md->virtual & PAGE_MASK;
phys = __pfn_to_phys(md->pfn);
length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
pr_warn("BUG: map for 0x%08llx at 0x%08lx can not be mapped using pages, ignoring.\n",
(long long)__pfn_to_phys(md->pfn), addr);
return;
}
pgd = pgd_offset(mm, addr);
end = addr + length;
do {
unsigned long next = pgd_addr_end(addr, end);
alloc_init_p4d(pgd, addr, next, phys, type, alloc, ng);
phys += next - addr;
addr = next;
} while (pgd++, addr != end);
}
/*
* Create the page directory entries and any necessary
* page tables for the mapping specified by `md'. We
* are able to cope here with varying sizes and address
* offsets, and we take full advantage of sections and
* supersections.
*/
static void __init create_mapping(struct map_desc *md)
{
if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
pr_warn("BUG: not creating mapping for 0x%08llx at 0x%08lx in user region\n",
(long long)__pfn_to_phys((u64)md->pfn), md->virtual);
return;
}
if (md->type == MT_DEVICE &&
md->virtual >= PAGE_OFFSET && md->virtual < FIXADDR_START &&
(md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n",
(long long)__pfn_to_phys((u64)md->pfn), md->virtual);
}
__create_mapping(&init_mm, md, early_alloc, false);
}
void __init create_mapping_late(struct mm_struct *mm, struct map_desc *md,
bool ng)
{
#ifdef CONFIG_ARM_LPAE
p4d_t *p4d;
pud_t *pud;
p4d = p4d_alloc(mm, pgd_offset(mm, md->virtual), md->virtual);
if (WARN_ON(!p4d))
return;
pud = pud_alloc(mm, p4d, md->virtual);
if (WARN_ON(!pud))
return;
pmd_alloc(mm, pud, 0);
#endif
__create_mapping(mm, md, late_alloc, ng);
}
/*
* Create the architecture specific mappings
*/
void __init iotable_init(struct map_desc *io_desc, int nr)
{
struct map_desc *md;
struct vm_struct *vm;
struct static_vm *svm;
if (!nr)
return;
svm = memblock_alloc(sizeof(*svm) * nr, __alignof__(*svm));
if (!svm)
panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
__func__, sizeof(*svm) * nr, __alignof__(*svm));
for (md = io_desc; nr; md++, nr--) {
create_mapping(md);
vm = &svm->vm;