a51324c430
Rework the way physical pages are set no-dat / dat: The old way is: - Rely on that all pages are initially marked "dat" - Allocate page tables for the kernel mapping - Enable dat - Walk the whole kernel mapping and set PG_arch_1 bit in all struct pages that belong to pages of kernel page tables - Walk all struct pages and test and clear the PG_arch_1 bit. If the bit is not set, set the page state to no-dat - For all subsequent page table allocations, set the page state to dat (remove the no-dat state) on allocation time Change this rather complex logic to a simpler approach: - Set the whole physical memory (all pages) to "no-dat" - Explicitly set those page table pages to "dat" which are part of the kernel image (e.g. swapper_pg_dir) - For all subsequent page table allocations, set the page state to dat (remove the no-dat state) on allocation time In result the code is simpler, and this also allows to get rid of one odd usage of the PG_arch_1 bit. Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
675 lines
16 KiB
C
675 lines
16 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright IBM Corp. 2006
|
|
*/
|
|
|
|
#include <linux/memory_hotplug.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/pfn.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/init.h>
|
|
#include <linux/list.h>
|
|
#include <linux/hugetlb.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/sort.h>
|
|
#include <asm/page-states.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/nospec-branch.h>
|
|
#include <asm/ctlreg.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/setup.h>
|
|
#include <asm/tlbflush.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/set_memory.h>
|
|
|
|
static DEFINE_MUTEX(vmem_mutex);
|
|
|
|
static void __ref *vmem_alloc_pages(unsigned int order)
|
|
{
|
|
unsigned long size = PAGE_SIZE << order;
|
|
|
|
if (slab_is_available())
|
|
return (void *)__get_free_pages(GFP_KERNEL, order);
|
|
return memblock_alloc(size, size);
|
|
}
|
|
|
|
static void vmem_free_pages(unsigned long addr, int order)
|
|
{
|
|
/* We don't expect boot memory to be removed ever. */
|
|
if (!slab_is_available() ||
|
|
WARN_ON_ONCE(PageReserved(virt_to_page((void *)addr))))
|
|
return;
|
|
free_pages(addr, order);
|
|
}
|
|
|
|
void *vmem_crst_alloc(unsigned long val)
|
|
{
|
|
unsigned long *table;
|
|
|
|
table = vmem_alloc_pages(CRST_ALLOC_ORDER);
|
|
if (!table)
|
|
return NULL;
|
|
crst_table_init(table, val);
|
|
__arch_set_page_dat(table, 1UL << CRST_ALLOC_ORDER);
|
|
return table;
|
|
}
|
|
|
|
pte_t __ref *vmem_pte_alloc(void)
|
|
{
|
|
unsigned long size = PTRS_PER_PTE * sizeof(pte_t);
|
|
pte_t *pte;
|
|
|
|
if (slab_is_available())
|
|
pte = (pte_t *) page_table_alloc(&init_mm);
|
|
else
|
|
pte = (pte_t *) memblock_alloc(size, size);
|
|
if (!pte)
|
|
return NULL;
|
|
memset64((u64 *)pte, _PAGE_INVALID, PTRS_PER_PTE);
|
|
__arch_set_page_dat(pte, 1);
|
|
return pte;
|
|
}
|
|
|
|
static void vmem_pte_free(unsigned long *table)
|
|
{
|
|
/* We don't expect boot memory to be removed ever. */
|
|
if (!slab_is_available() ||
|
|
WARN_ON_ONCE(PageReserved(virt_to_page(table))))
|
|
return;
|
|
page_table_free(&init_mm, table);
|
|
}
|
|
|
|
#define PAGE_UNUSED 0xFD
|
|
|
|
/*
|
|
* The unused vmemmap range, which was not yet memset(PAGE_UNUSED) ranges
|
|
* from unused_sub_pmd_start to next PMD_SIZE boundary.
|
|
*/
|
|
static unsigned long unused_sub_pmd_start;
|
|
|
|
static void vmemmap_flush_unused_sub_pmd(void)
|
|
{
|
|
if (!unused_sub_pmd_start)
|
|
return;
|
|
memset((void *)unused_sub_pmd_start, PAGE_UNUSED,
|
|
ALIGN(unused_sub_pmd_start, PMD_SIZE) - unused_sub_pmd_start);
|
|
unused_sub_pmd_start = 0;
|
|
}
|
|
|
|
static void vmemmap_mark_sub_pmd_used(unsigned long start, unsigned long end)
|
|
{
|
|
/*
|
|
* As we expect to add in the same granularity as we remove, it's
|
|
* sufficient to mark only some piece used to block the memmap page from
|
|
* getting removed (just in case the memmap never gets initialized,
|
|
* e.g., because the memory block never gets onlined).
|
|
*/
|
|
memset((void *)start, 0, sizeof(struct page));
|
|
}
|
|
|
|
static void vmemmap_use_sub_pmd(unsigned long start, unsigned long end)
|
|
{
|
|
/*
|
|
* We only optimize if the new used range directly follows the
|
|
* previously unused range (esp., when populating consecutive sections).
|
|
*/
|
|
if (unused_sub_pmd_start == start) {
|
|
unused_sub_pmd_start = end;
|
|
if (likely(IS_ALIGNED(unused_sub_pmd_start, PMD_SIZE)))
|
|
unused_sub_pmd_start = 0;
|
|
return;
|
|
}
|
|
vmemmap_flush_unused_sub_pmd();
|
|
vmemmap_mark_sub_pmd_used(start, end);
|
|
}
|
|
|
|
static void vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
|
|
{
|
|
unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
|
|
|
|
vmemmap_flush_unused_sub_pmd();
|
|
|
|
/* Could be our memmap page is filled with PAGE_UNUSED already ... */
|
|
vmemmap_mark_sub_pmd_used(start, end);
|
|
|
|
/* Mark the unused parts of the new memmap page PAGE_UNUSED. */
|
|
if (!IS_ALIGNED(start, PMD_SIZE))
|
|
memset((void *)page, PAGE_UNUSED, start - page);
|
|
/*
|
|
* We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of
|
|
* consecutive sections. Remember for the last added PMD the last
|
|
* unused range in the populated PMD.
|
|
*/
|
|
if (!IS_ALIGNED(end, PMD_SIZE))
|
|
unused_sub_pmd_start = end;
|
|
}
|
|
|
|
/* Returns true if the PMD is completely unused and can be freed. */
|
|
static bool vmemmap_unuse_sub_pmd(unsigned long start, unsigned long end)
|
|
{
|
|
unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
|
|
|
|
vmemmap_flush_unused_sub_pmd();
|
|
memset((void *)start, PAGE_UNUSED, end - start);
|
|
return !memchr_inv((void *)page, PAGE_UNUSED, PMD_SIZE);
|
|
}
|
|
|
|
/* __ref: we'll only call vmemmap_alloc_block() via vmemmap_populate() */
|
|
static int __ref modify_pte_table(pmd_t *pmd, unsigned long addr,
|
|
unsigned long end, bool add, bool direct)
|
|
{
|
|
unsigned long prot, pages = 0;
|
|
int ret = -ENOMEM;
|
|
pte_t *pte;
|
|
|
|
prot = pgprot_val(PAGE_KERNEL);
|
|
if (!MACHINE_HAS_NX)
|
|
prot &= ~_PAGE_NOEXEC;
|
|
|
|
pte = pte_offset_kernel(pmd, addr);
|
|
for (; addr < end; addr += PAGE_SIZE, pte++) {
|
|
if (!add) {
|
|
if (pte_none(*pte))
|
|
continue;
|
|
if (!direct)
|
|
vmem_free_pages((unsigned long) pfn_to_virt(pte_pfn(*pte)), 0);
|
|
pte_clear(&init_mm, addr, pte);
|
|
} else if (pte_none(*pte)) {
|
|
if (!direct) {
|
|
void *new_page = vmemmap_alloc_block(PAGE_SIZE, NUMA_NO_NODE);
|
|
|
|
if (!new_page)
|
|
goto out;
|
|
set_pte(pte, __pte(__pa(new_page) | prot));
|
|
} else {
|
|
set_pte(pte, __pte(__pa(addr) | prot));
|
|
}
|
|
} else {
|
|
continue;
|
|
}
|
|
pages++;
|
|
}
|
|
ret = 0;
|
|
out:
|
|
if (direct)
|
|
update_page_count(PG_DIRECT_MAP_4K, add ? pages : -pages);
|
|
return ret;
|
|
}
|
|
|
|
static void try_free_pte_table(pmd_t *pmd, unsigned long start)
|
|
{
|
|
pte_t *pte;
|
|
int i;
|
|
|
|
/* We can safely assume this is fully in 1:1 mapping & vmemmap area */
|
|
pte = pte_offset_kernel(pmd, start);
|
|
for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
|
|
if (!pte_none(*pte))
|
|
return;
|
|
}
|
|
vmem_pte_free((unsigned long *) pmd_deref(*pmd));
|
|
pmd_clear(pmd);
|
|
}
|
|
|
|
/* __ref: we'll only call vmemmap_alloc_block() via vmemmap_populate() */
|
|
static int __ref modify_pmd_table(pud_t *pud, unsigned long addr,
|
|
unsigned long end, bool add, bool direct)
|
|
{
|
|
unsigned long next, prot, pages = 0;
|
|
int ret = -ENOMEM;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
|
|
prot = pgprot_val(SEGMENT_KERNEL);
|
|
if (!MACHINE_HAS_NX)
|
|
prot &= ~_SEGMENT_ENTRY_NOEXEC;
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
for (; addr < end; addr = next, pmd++) {
|
|
next = pmd_addr_end(addr, end);
|
|
if (!add) {
|
|
if (pmd_none(*pmd))
|
|
continue;
|
|
if (pmd_large(*pmd)) {
|
|
if (IS_ALIGNED(addr, PMD_SIZE) &&
|
|
IS_ALIGNED(next, PMD_SIZE)) {
|
|
if (!direct)
|
|
vmem_free_pages(pmd_deref(*pmd), get_order(PMD_SIZE));
|
|
pmd_clear(pmd);
|
|
pages++;
|
|
} else if (!direct && vmemmap_unuse_sub_pmd(addr, next)) {
|
|
vmem_free_pages(pmd_deref(*pmd), get_order(PMD_SIZE));
|
|
pmd_clear(pmd);
|
|
}
|
|
continue;
|
|
}
|
|
} else if (pmd_none(*pmd)) {
|
|
if (IS_ALIGNED(addr, PMD_SIZE) &&
|
|
IS_ALIGNED(next, PMD_SIZE) &&
|
|
MACHINE_HAS_EDAT1 && direct &&
|
|
!debug_pagealloc_enabled()) {
|
|
set_pmd(pmd, __pmd(__pa(addr) | prot));
|
|
pages++;
|
|
continue;
|
|
} else if (!direct && MACHINE_HAS_EDAT1) {
|
|
void *new_page;
|
|
|
|
/*
|
|
* Use 1MB frames for vmemmap if available. We
|
|
* always use large frames even if they are only
|
|
* partially used. Otherwise we would have also
|
|
* page tables since vmemmap_populate gets
|
|
* called for each section separately.
|
|
*/
|
|
new_page = vmemmap_alloc_block(PMD_SIZE, NUMA_NO_NODE);
|
|
if (new_page) {
|
|
set_pmd(pmd, __pmd(__pa(new_page) | prot));
|
|
if (!IS_ALIGNED(addr, PMD_SIZE) ||
|
|
!IS_ALIGNED(next, PMD_SIZE)) {
|
|
vmemmap_use_new_sub_pmd(addr, next);
|
|
}
|
|
continue;
|
|
}
|
|
}
|
|
pte = vmem_pte_alloc();
|
|
if (!pte)
|
|
goto out;
|
|
pmd_populate(&init_mm, pmd, pte);
|
|
} else if (pmd_large(*pmd)) {
|
|
if (!direct)
|
|
vmemmap_use_sub_pmd(addr, next);
|
|
continue;
|
|
}
|
|
ret = modify_pte_table(pmd, addr, next, add, direct);
|
|
if (ret)
|
|
goto out;
|
|
if (!add)
|
|
try_free_pte_table(pmd, addr & PMD_MASK);
|
|
}
|
|
ret = 0;
|
|
out:
|
|
if (direct)
|
|
update_page_count(PG_DIRECT_MAP_1M, add ? pages : -pages);
|
|
return ret;
|
|
}
|
|
|
|
static void try_free_pmd_table(pud_t *pud, unsigned long start)
|
|
{
|
|
pmd_t *pmd;
|
|
int i;
|
|
|
|
pmd = pmd_offset(pud, start);
|
|
for (i = 0; i < PTRS_PER_PMD; i++, pmd++)
|
|
if (!pmd_none(*pmd))
|
|
return;
|
|
vmem_free_pages(pud_deref(*pud), CRST_ALLOC_ORDER);
|
|
pud_clear(pud);
|
|
}
|
|
|
|
static int modify_pud_table(p4d_t *p4d, unsigned long addr, unsigned long end,
|
|
bool add, bool direct)
|
|
{
|
|
unsigned long next, prot, pages = 0;
|
|
int ret = -ENOMEM;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
|
|
prot = pgprot_val(REGION3_KERNEL);
|
|
if (!MACHINE_HAS_NX)
|
|
prot &= ~_REGION_ENTRY_NOEXEC;
|
|
pud = pud_offset(p4d, addr);
|
|
for (; addr < end; addr = next, pud++) {
|
|
next = pud_addr_end(addr, end);
|
|
if (!add) {
|
|
if (pud_none(*pud))
|
|
continue;
|
|
if (pud_large(*pud)) {
|
|
if (IS_ALIGNED(addr, PUD_SIZE) &&
|
|
IS_ALIGNED(next, PUD_SIZE)) {
|
|
pud_clear(pud);
|
|
pages++;
|
|
}
|
|
continue;
|
|
}
|
|
} else if (pud_none(*pud)) {
|
|
if (IS_ALIGNED(addr, PUD_SIZE) &&
|
|
IS_ALIGNED(next, PUD_SIZE) &&
|
|
MACHINE_HAS_EDAT2 && direct &&
|
|
!debug_pagealloc_enabled()) {
|
|
set_pud(pud, __pud(__pa(addr) | prot));
|
|
pages++;
|
|
continue;
|
|
}
|
|
pmd = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
|
|
if (!pmd)
|
|
goto out;
|
|
pud_populate(&init_mm, pud, pmd);
|
|
} else if (pud_large(*pud)) {
|
|
continue;
|
|
}
|
|
ret = modify_pmd_table(pud, addr, next, add, direct);
|
|
if (ret)
|
|
goto out;
|
|
if (!add)
|
|
try_free_pmd_table(pud, addr & PUD_MASK);
|
|
}
|
|
ret = 0;
|
|
out:
|
|
if (direct)
|
|
update_page_count(PG_DIRECT_MAP_2G, add ? pages : -pages);
|
|
return ret;
|
|
}
|
|
|
|
static void try_free_pud_table(p4d_t *p4d, unsigned long start)
|
|
{
|
|
pud_t *pud;
|
|
int i;
|
|
|
|
pud = pud_offset(p4d, start);
|
|
for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
|
|
if (!pud_none(*pud))
|
|
return;
|
|
}
|
|
vmem_free_pages(p4d_deref(*p4d), CRST_ALLOC_ORDER);
|
|
p4d_clear(p4d);
|
|
}
|
|
|
|
static int modify_p4d_table(pgd_t *pgd, unsigned long addr, unsigned long end,
|
|
bool add, bool direct)
|
|
{
|
|
unsigned long next;
|
|
int ret = -ENOMEM;
|
|
p4d_t *p4d;
|
|
pud_t *pud;
|
|
|
|
p4d = p4d_offset(pgd, addr);
|
|
for (; addr < end; addr = next, p4d++) {
|
|
next = p4d_addr_end(addr, end);
|
|
if (!add) {
|
|
if (p4d_none(*p4d))
|
|
continue;
|
|
} else if (p4d_none(*p4d)) {
|
|
pud = vmem_crst_alloc(_REGION3_ENTRY_EMPTY);
|
|
if (!pud)
|
|
goto out;
|
|
p4d_populate(&init_mm, p4d, pud);
|
|
}
|
|
ret = modify_pud_table(p4d, addr, next, add, direct);
|
|
if (ret)
|
|
goto out;
|
|
if (!add)
|
|
try_free_pud_table(p4d, addr & P4D_MASK);
|
|
}
|
|
ret = 0;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static void try_free_p4d_table(pgd_t *pgd, unsigned long start)
|
|
{
|
|
p4d_t *p4d;
|
|
int i;
|
|
|
|
p4d = p4d_offset(pgd, start);
|
|
for (i = 0; i < PTRS_PER_P4D; i++, p4d++) {
|
|
if (!p4d_none(*p4d))
|
|
return;
|
|
}
|
|
vmem_free_pages(pgd_deref(*pgd), CRST_ALLOC_ORDER);
|
|
pgd_clear(pgd);
|
|
}
|
|
|
|
static int modify_pagetable(unsigned long start, unsigned long end, bool add,
|
|
bool direct)
|
|
{
|
|
unsigned long addr, next;
|
|
int ret = -ENOMEM;
|
|
pgd_t *pgd;
|
|
p4d_t *p4d;
|
|
|
|
if (WARN_ON_ONCE(!PAGE_ALIGNED(start | end)))
|
|
return -EINVAL;
|
|
/* Don't mess with any tables not fully in 1:1 mapping & vmemmap area */
|
|
if (WARN_ON_ONCE(end > VMALLOC_START))
|
|
return -EINVAL;
|
|
for (addr = start; addr < end; addr = next) {
|
|
next = pgd_addr_end(addr, end);
|
|
pgd = pgd_offset_k(addr);
|
|
|
|
if (!add) {
|
|
if (pgd_none(*pgd))
|
|
continue;
|
|
} else if (pgd_none(*pgd)) {
|
|
p4d = vmem_crst_alloc(_REGION2_ENTRY_EMPTY);
|
|
if (!p4d)
|
|
goto out;
|
|
pgd_populate(&init_mm, pgd, p4d);
|
|
}
|
|
ret = modify_p4d_table(pgd, addr, next, add, direct);
|
|
if (ret)
|
|
goto out;
|
|
if (!add)
|
|
try_free_p4d_table(pgd, addr & PGDIR_MASK);
|
|
}
|
|
ret = 0;
|
|
out:
|
|
if (!add)
|
|
flush_tlb_kernel_range(start, end);
|
|
return ret;
|
|
}
|
|
|
|
static int add_pagetable(unsigned long start, unsigned long end, bool direct)
|
|
{
|
|
return modify_pagetable(start, end, true, direct);
|
|
}
|
|
|
|
static int remove_pagetable(unsigned long start, unsigned long end, bool direct)
|
|
{
|
|
return modify_pagetable(start, end, false, direct);
|
|
}
|
|
|
|
/*
|
|
* Add a physical memory range to the 1:1 mapping.
|
|
*/
|
|
static int vmem_add_range(unsigned long start, unsigned long size)
|
|
{
|
|
start = (unsigned long)__va(start);
|
|
return add_pagetable(start, start + size, true);
|
|
}
|
|
|
|
/*
|
|
* Remove a physical memory range from the 1:1 mapping.
|
|
*/
|
|
static void vmem_remove_range(unsigned long start, unsigned long size)
|
|
{
|
|
start = (unsigned long)__va(start);
|
|
remove_pagetable(start, start + size, true);
|
|
}
|
|
|
|
/*
|
|
* Add a backed mem_map array to the virtual mem_map array.
|
|
*/
|
|
int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
|
|
struct vmem_altmap *altmap)
|
|
{
|
|
int ret;
|
|
|
|
mutex_lock(&vmem_mutex);
|
|
/* We don't care about the node, just use NUMA_NO_NODE on allocations */
|
|
ret = add_pagetable(start, end, false);
|
|
if (ret)
|
|
remove_pagetable(start, end, false);
|
|
mutex_unlock(&vmem_mutex);
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
|
|
void vmemmap_free(unsigned long start, unsigned long end,
|
|
struct vmem_altmap *altmap)
|
|
{
|
|
mutex_lock(&vmem_mutex);
|
|
remove_pagetable(start, end, false);
|
|
mutex_unlock(&vmem_mutex);
|
|
}
|
|
|
|
#endif
|
|
|
|
void vmem_remove_mapping(unsigned long start, unsigned long size)
|
|
{
|
|
mutex_lock(&vmem_mutex);
|
|
vmem_remove_range(start, size);
|
|
mutex_unlock(&vmem_mutex);
|
|
}
|
|
|
|
struct range arch_get_mappable_range(void)
|
|
{
|
|
struct range mhp_range;
|
|
|
|
mhp_range.start = 0;
|
|
mhp_range.end = max_mappable - 1;
|
|
return mhp_range;
|
|
}
|
|
|
|
int vmem_add_mapping(unsigned long start, unsigned long size)
|
|
{
|
|
struct range range = arch_get_mappable_range();
|
|
int ret;
|
|
|
|
if (start < range.start ||
|
|
start + size > range.end + 1 ||
|
|
start + size < start)
|
|
return -ERANGE;
|
|
|
|
mutex_lock(&vmem_mutex);
|
|
ret = vmem_add_range(start, size);
|
|
if (ret)
|
|
vmem_remove_range(start, size);
|
|
mutex_unlock(&vmem_mutex);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Allocate new or return existing page-table entry, but do not map it
|
|
* to any physical address. If missing, allocate segment- and region-
|
|
* table entries along. Meeting a large segment- or region-table entry
|
|
* while traversing is an error, since the function is expected to be
|
|
* called against virtual regions reserved for 4KB mappings only.
|
|
*/
|
|
pte_t *vmem_get_alloc_pte(unsigned long addr, bool alloc)
|
|
{
|
|
pte_t *ptep = NULL;
|
|
pgd_t *pgd;
|
|
p4d_t *p4d;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
|
|
pgd = pgd_offset_k(addr);
|
|
if (pgd_none(*pgd)) {
|
|
if (!alloc)
|
|
goto out;
|
|
p4d = vmem_crst_alloc(_REGION2_ENTRY_EMPTY);
|
|
if (!p4d)
|
|
goto out;
|
|
pgd_populate(&init_mm, pgd, p4d);
|
|
}
|
|
p4d = p4d_offset(pgd, addr);
|
|
if (p4d_none(*p4d)) {
|
|
if (!alloc)
|
|
goto out;
|
|
pud = vmem_crst_alloc(_REGION3_ENTRY_EMPTY);
|
|
if (!pud)
|
|
goto out;
|
|
p4d_populate(&init_mm, p4d, pud);
|
|
}
|
|
pud = pud_offset(p4d, addr);
|
|
if (pud_none(*pud)) {
|
|
if (!alloc)
|
|
goto out;
|
|
pmd = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
|
|
if (!pmd)
|
|
goto out;
|
|
pud_populate(&init_mm, pud, pmd);
|
|
} else if (WARN_ON_ONCE(pud_large(*pud))) {
|
|
goto out;
|
|
}
|
|
pmd = pmd_offset(pud, addr);
|
|
if (pmd_none(*pmd)) {
|
|
if (!alloc)
|
|
goto out;
|
|
pte = vmem_pte_alloc();
|
|
if (!pte)
|
|
goto out;
|
|
pmd_populate(&init_mm, pmd, pte);
|
|
} else if (WARN_ON_ONCE(pmd_large(*pmd))) {
|
|
goto out;
|
|
}
|
|
ptep = pte_offset_kernel(pmd, addr);
|
|
out:
|
|
return ptep;
|
|
}
|
|
|
|
int __vmem_map_4k_page(unsigned long addr, unsigned long phys, pgprot_t prot, bool alloc)
|
|
{
|
|
pte_t *ptep, pte;
|
|
|
|
if (!IS_ALIGNED(addr, PAGE_SIZE))
|
|
return -EINVAL;
|
|
ptep = vmem_get_alloc_pte(addr, alloc);
|
|
if (!ptep)
|
|
return -ENOMEM;
|
|
__ptep_ipte(addr, ptep, 0, 0, IPTE_GLOBAL);
|
|
pte = mk_pte_phys(phys, prot);
|
|
set_pte(ptep, pte);
|
|
return 0;
|
|
}
|
|
|
|
int vmem_map_4k_page(unsigned long addr, unsigned long phys, pgprot_t prot)
|
|
{
|
|
int rc;
|
|
|
|
mutex_lock(&vmem_mutex);
|
|
rc = __vmem_map_4k_page(addr, phys, prot, true);
|
|
mutex_unlock(&vmem_mutex);
|
|
return rc;
|
|
}
|
|
|
|
void vmem_unmap_4k_page(unsigned long addr)
|
|
{
|
|
pte_t *ptep;
|
|
|
|
mutex_lock(&vmem_mutex);
|
|
ptep = virt_to_kpte(addr);
|
|
__ptep_ipte(addr, ptep, 0, 0, IPTE_GLOBAL);
|
|
pte_clear(&init_mm, addr, ptep);
|
|
mutex_unlock(&vmem_mutex);
|
|
}
|
|
|
|
void __init vmem_map_init(void)
|
|
{
|
|
__set_memory_rox(_stext, _etext);
|
|
__set_memory_ro(_etext, __end_rodata);
|
|
__set_memory_rox(_sinittext, _einittext);
|
|
__set_memory_rox(__stext_amode31, __etext_amode31);
|
|
/*
|
|
* If the BEAR-enhancement facility is not installed the first
|
|
* prefix page is used to return to the previous context with
|
|
* an LPSWE instruction and therefore must be executable.
|
|
*/
|
|
if (!static_key_enabled(&cpu_has_bear))
|
|
set_memory_x(0, 1);
|
|
if (debug_pagealloc_enabled()) {
|
|
/*
|
|
* Use RELOC_HIDE() as long as __va(0) translates to NULL,
|
|
* since performing pointer arithmetic on a NULL pointer
|
|
* has undefined behavior and generates compiler warnings.
|
|
*/
|
|
__set_memory_4k(__va(0), RELOC_HIDE(__va(0), ident_map_size));
|
|
}
|
|
if (MACHINE_HAS_NX)
|
|
system_ctl_set_bit(0, CR0_INSTRUCTION_EXEC_PROTECTION_BIT);
|
|
pr_info("Write protected kernel read-only data: %luk\n",
|
|
(unsigned long)(__end_rodata - _stext) >> 10);
|
|
}
|