diff options
| -rw-r--r-- | arch/s390/lib/uaccess_pt.c | 85 |
1 files changed, 22 insertions, 63 deletions
diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c index b159a9d..dc37ea8 100644 --- a/arch/s390/lib/uaccess_pt.c +++ b/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 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; |
