kernel_optimize_test/arch/s390/mm/pageattr.c
Martin Schwidefsky e509861105 s390/mm: cleanup page table definitions
Improve the encoding of the different pte types and the naming of the
page, segment table and region table bits. Due to the different pte
encoding the hugetlbfs primitives need to be adapted as well. To improve
compatability with common code make the huge ptes use the encoding of
normal ptes. The conversion between the pte and pmd encoding for a huge
pte is done with set_huge_pte_at and huge_ptep_get.
Overall the code is now easier to understand.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:06 +02:00

145 lines
2.9 KiB
C

/*
* Copyright IBM Corp. 2011
* Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
*/
#include <linux/hugetlb.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <asm/cacheflush.h>
#include <asm/pgtable.h>
#include <asm/page.h>
static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
{
asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],9,0"
: [addr] "+a" (addr) : [skey] "d" (skey));
return addr;
}
void storage_key_init_range(unsigned long start, unsigned long end)
{
unsigned long boundary, size;
while (start < end) {
if (MACHINE_HAS_EDAT1) {
/* set storage keys for a 1MB frame */
size = 1UL << 20;
boundary = (start + size) & ~(size - 1);
if (boundary <= end) {
do {
start = sske_frame(start, PAGE_DEFAULT_KEY);
} while (start < boundary);
continue;
}
}
page_set_storage_key(start, PAGE_DEFAULT_KEY, 0);
start += PAGE_SIZE;
}
}
static pte_t *walk_page_table(unsigned long addr)
{
pgd_t *pgdp;
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
pgdp = pgd_offset_k(addr);
if (pgd_none(*pgdp))
return NULL;
pudp = pud_offset(pgdp, addr);
if (pud_none(*pudp) || pud_large(*pudp))
return NULL;
pmdp = pmd_offset(pudp, addr);
if (pmd_none(*pmdp) || pmd_large(*pmdp))
return NULL;
ptep = pte_offset_kernel(pmdp, addr);
if (pte_none(*ptep))
return NULL;
return ptep;
}
static void change_page_attr(unsigned long addr, int numpages,
pte_t (*set) (pte_t))
{
pte_t *ptep, pte;
int i;
for (i = 0; i < numpages; i++) {
ptep = walk_page_table(addr);
if (WARN_ON_ONCE(!ptep))
break;
pte = *ptep;
pte = set(pte);
__ptep_ipte(addr, ptep);
*ptep = pte;
addr += PAGE_SIZE;
}
}
int set_memory_ro(unsigned long addr, int numpages)
{
change_page_attr(addr, numpages, pte_wrprotect);
return 0;
}
int set_memory_rw(unsigned long addr, int numpages)
{
change_page_attr(addr, numpages, pte_mkwrite);
return 0;
}
/* not possible */
int set_memory_nx(unsigned long addr, int numpages)
{
return 0;
}
int set_memory_x(unsigned long addr, int numpages)
{
return 0;
}
#ifdef CONFIG_DEBUG_PAGEALLOC
void kernel_map_pages(struct page *page, int numpages, int enable)
{
unsigned long address;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
int i;
for (i = 0; i < numpages; i++) {
address = page_to_phys(page + i);
pgd = pgd_offset_k(address);
pud = pud_offset(pgd, address);
pmd = pmd_offset(pud, address);
pte = pte_offset_kernel(pmd, address);
if (!enable) {
__ptep_ipte(address, pte);
pte_val(*pte) = _PAGE_INVALID;
continue;
}
pte_val(*pte) = __pa(address);
}
}
#ifdef CONFIG_HIBERNATION
bool kernel_page_present(struct page *page)
{
unsigned long addr;
int cc;
addr = page_to_phys(page);
asm volatile(
" lra %1,0(%1)\n"
" ipm %0\n"
" srl %0,28"
: "=d" (cc), "+a" (addr) : : "cc");
return cc == 0;
}
#endif /* CONFIG_HIBERNATION */
#endif /* CONFIG_DEBUG_PAGEALLOC */