From: Martin Schwidefsky <[email protected]>
Define and use follow_table inline in uaccess_pt.c to simplify
the code.
Signed-off-by: Martin Schwidefsky <[email protected]>
---
arch/s390/lib/uaccess_pt.c | 85 +++++++++++----------------------------------
1 file changed, 22 insertions(+), 63 deletions(-)
Index: quilt-2.6/arch/s390/lib/uaccess_pt.c
===================================================================
--- quilt-2.6.orig/arch/s390/lib/uaccess_pt.c
+++ quilt-2.6/arch/s390/lib/uaccess_pt.c
@@ -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 lo
{
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 lo
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(uns
{
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 cou
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 cou
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,
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,
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;
--
blue skies,
Martin.
"Reality continues to ruin my life." - Calvin.
-
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