linux/arch/s390/mm/pageattr.c
Heiko Carstens 5a79859ae0 s390: remove 31 bit support
Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.

The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e58 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.

Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25 11:49:33 +01:00

171 lines
3.4 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/facility.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#if PAGE_DEFAULT_KEY
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;
}
}
#endif
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
static void ipte_range(pte_t *pte, unsigned long address, int nr)
{
int i;
if (test_facility(13)) {
__ptep_ipte_range(address, nr - 1, pte);
return;
}
for (i = 0; i < nr; i++) {
__ptep_ipte(address, pte);
address += PAGE_SIZE;
pte++;
}
}
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
unsigned long address;
int nr, i, j;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
for (i = 0; i < numpages;) {
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);
nr = (unsigned long)pte >> ilog2(sizeof(long));
nr = PTRS_PER_PTE - (nr & (PTRS_PER_PTE - 1));
nr = min(numpages - i, nr);
if (enable) {
for (j = 0; j < nr; j++) {
pte_val(*pte) = __pa(address);
address += PAGE_SIZE;
pte++;
}
} else {
ipte_range(pte, address, nr);
}
i += nr;
}
}
#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 */