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path: root/arch/arm/lib/uaccess_with_memcpy.c
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Diffstat (limited to 'arch/arm/lib/uaccess_with_memcpy.c')
-rw-r--r--arch/arm/lib/uaccess_with_memcpy.c46
1 files changed, 22 insertions, 24 deletions
diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c
index c9450982a155..c0ac7796d775 100644
--- a/arch/arm/lib/uaccess_with_memcpy.c
+++ b/arch/arm/lib/uaccess_with_memcpy.c
@@ -24,6 +24,7 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
{
unsigned long addr = (unsigned long)_addr;
pgd_t *pgd;
+ p4d_t *p4d;
pmd_t *pmd;
pte_t *pte;
pud_t *pud;
@@ -33,7 +34,11 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
if (unlikely(pgd_none(*pgd) || pgd_bad(*pgd)))
return 0;
- pud = pud_offset(pgd, addr);
+ p4d = p4d_offset(pgd, addr);
+ if (unlikely(p4d_none(*p4d) || p4d_bad(*p4d)))
+ return 0;
+
+ pud = pud_offset(p4d, addr);
if (unlikely(pud_none(*pud) || pud_bad(*pud)))
return 0;
@@ -51,10 +56,10 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
* to see that it's still huge and whether or not we will
* need to fault on write.
*/
- if (unlikely(pmd_thp_or_huge(*pmd))) {
+ if (unlikely(pmd_leaf(*pmd))) {
ptl = &current->mm->page_table_lock;
spin_lock(ptl);
- if (unlikely(!pmd_thp_or_huge(*pmd)
+ if (unlikely(!pmd_leaf(*pmd)
|| pmd_hugewillfault(*pmd))) {
spin_unlock(ptl);
return 0;
@@ -69,6 +74,9 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
return 0;
pte = pte_offset_map_lock(current->mm, pmd, addr, &ptl);
+ if (unlikely(!pte))
+ return 0;
+
if (unlikely(!pte_present(*pte) || !pte_young(*pte) ||
!pte_write(*pte) || !pte_dirty(*pte))) {
pte_unmap_unlock(pte, ptl);
@@ -87,16 +95,11 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
unsigned long ua_flags;
int atomic;
- if (uaccess_kernel()) {
- memcpy((void *)to, from, n);
- return 0;
- }
-
/* the mmap semaphore is taken only if not in an atomic context */
atomic = faulthandler_disabled();
if (!atomic)
- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
while (n) {
pte_t *pte;
spinlock_t *ptl;
@@ -104,11 +107,11 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
while (!pin_page_for_write(to, &pte, &ptl)) {
if (!atomic)
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
if (__put_user(0, (char __user *)to))
goto out;
if (!atomic)
- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
}
tocopy = (~(unsigned long)to & ~PAGE_MASK) + 1;
@@ -116,7 +119,7 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
tocopy = n;
ua_flags = uaccess_save_and_enable();
- memcpy((void *)to, from, tocopy);
+ __memcpy((void *)to, from, tocopy);
uaccess_restore(ua_flags);
to += tocopy;
from += tocopy;
@@ -128,7 +131,7 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
spin_unlock(ptl);
}
if (!atomic)
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
out:
return n;
@@ -160,22 +163,17 @@ __clear_user_memset(void __user *addr, unsigned long n)
{
unsigned long ua_flags;
- if (uaccess_kernel()) {
- memset((void *)addr, 0, n);
- return 0;
- }
-
- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
while (n) {
pte_t *pte;
spinlock_t *ptl;
int tocopy;
while (!pin_page_for_write(addr, &pte, &ptl)) {
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
if (__put_user(0, (char __user *)addr))
goto out;
- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
}
tocopy = (~(unsigned long)addr & ~PAGE_MASK) + 1;
@@ -183,7 +181,7 @@ __clear_user_memset(void __user *addr, unsigned long n)
tocopy = n;
ua_flags = uaccess_save_and_enable();
- memset((void *)addr, 0, tocopy);
+ __memset((void *)addr, 0, tocopy);
uaccess_restore(ua_flags);
addr += tocopy;
n -= tocopy;
@@ -193,7 +191,7 @@ __clear_user_memset(void __user *addr, unsigned long n)
else
spin_unlock(ptl);
}
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
out:
return n;
@@ -242,7 +240,7 @@ static int __init test_size_treshold(void)
if (!dst_page)
goto no_dst;
kernel_ptr = page_address(src_page);
- user_ptr = vmap(&dst_page, 1, VM_IOREMAP, __pgprot(__P010));
+ user_ptr = vmap(&dst_page, 1, VM_IOREMAP, __pgprot(__PAGE_COPY));
if (!user_ptr)
goto no_vmap;