[S390] Introduce follow_table in uaccess_pt.c

Define and use follow_table inline in uaccess_pt.c to simplify
the code.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2007-10-22 12:52:46 +02:00
parent 6f3fa3f0eb
commit e4aa402e7a
1 changed files with 22 additions and 63 deletions

View File

@ -15,6 +15,22 @@
#include <asm/futex.h>
#include "uaccess.h"
static inline pte_t *follow_table(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pmd_t *pmd;
pgd = pgd_offset(mm, addr);
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
return NULL;
pmd = pmd_offset(pgd, addr);
if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
return NULL;
return pte_offset_map(pmd, addr);
}
static int __handle_fault(struct mm_struct *mm, unsigned long address,
int write_access)
{
@ -85,8 +101,6 @@ static size_t __user_copy_pt(unsigned long uaddr, void *kptr,
{
struct mm_struct *mm = current->mm;
unsigned long offset, pfn, done, size;
pgd_t *pgd;
pmd_t *pmd;
pte_t *pte;
void *from, *to;
@ -94,15 +108,7 @@ static size_t __user_copy_pt(unsigned long uaddr, void *kptr,
retry:
spin_lock(&mm->page_table_lock);
do {
pgd = pgd_offset(mm, uaddr);
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
goto fault;
pmd = pmd_offset(pgd, uaddr);
if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
goto fault;
pte = pte_offset_map(pmd, uaddr);
pte = follow_table(mm, uaddr);
if (!pte || !pte_present(*pte) ||
(write_user && !pte_write(*pte)))
goto fault;
@ -142,22 +148,12 @@ static unsigned long __dat_user_addr(unsigned long uaddr)
{
struct mm_struct *mm = current->mm;
unsigned long pfn, ret;
pgd_t *pgd;
pmd_t *pmd;
pte_t *pte;
int rc;
ret = 0;
retry:
pgd = pgd_offset(mm, uaddr);
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
goto fault;
pmd = pmd_offset(pgd, uaddr);
if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
goto fault;
pte = pte_offset_map(pmd, uaddr);
pte = follow_table(mm, uaddr);
if (!pte || !pte_present(*pte))
goto fault;
@ -229,8 +225,6 @@ static size_t strnlen_user_pt(size_t count, const char __user *src)
unsigned long uaddr = (unsigned long) src;
struct mm_struct *mm = current->mm;
unsigned long offset, pfn, done, len;
pgd_t *pgd;
pmd_t *pmd;
pte_t *pte;
size_t len_str;
@ -240,15 +234,7 @@ static size_t strnlen_user_pt(size_t count, const char __user *src)
retry:
spin_lock(&mm->page_table_lock);
do {
pgd = pgd_offset(mm, uaddr);
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
goto fault;
pmd = pmd_offset(pgd, uaddr);
if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
goto fault;
pte = pte_offset_map(pmd, uaddr);
pte = follow_table(mm, uaddr);
if (!pte || !pte_present(*pte))
goto fault;
@ -308,8 +294,6 @@ static size_t copy_in_user_pt(size_t n, void __user *to,
uaddr, done, size;
unsigned long uaddr_from = (unsigned long) from;
unsigned long uaddr_to = (unsigned long) to;
pgd_t *pgd_from, *pgd_to;
pmd_t *pmd_from, *pmd_to;
pte_t *pte_from, *pte_to;
int write_user;
@ -317,39 +301,14 @@ static size_t copy_in_user_pt(size_t n, void __user *to,
retry:
spin_lock(&mm->page_table_lock);
do {
pgd_from = pgd_offset(mm, uaddr_from);
if (pgd_none(*pgd_from) || unlikely(pgd_bad(*pgd_from))) {
uaddr = uaddr_from;
write_user = 0;
goto fault;
}
pgd_to = pgd_offset(mm, uaddr_to);
if (pgd_none(*pgd_to) || unlikely(pgd_bad(*pgd_to))) {
uaddr = uaddr_to;
write_user = 1;
goto fault;
}
pmd_from = pmd_offset(pgd_from, uaddr_from);
if (pmd_none(*pmd_from) || unlikely(pmd_bad(*pmd_from))) {
uaddr = uaddr_from;
write_user = 0;
goto fault;
}
pmd_to = pmd_offset(pgd_to, uaddr_to);
if (pmd_none(*pmd_to) || unlikely(pmd_bad(*pmd_to))) {
uaddr = uaddr_to;
write_user = 1;
goto fault;
}
pte_from = pte_offset_map(pmd_from, uaddr_from);
pte_from = follow_table(mm, uaddr_from);
if (!pte_from || !pte_present(*pte_from)) {
uaddr = uaddr_from;
write_user = 0;
goto fault;
}
pte_to = pte_offset_map(pmd_to, uaddr_to);
pte_to = follow_table(mm, uaddr_to);
if (!pte_to || !pte_present(*pte_to) || !pte_write(*pte_to)) {
uaddr = uaddr_to;
write_user = 1;