Currently on nommu arch mmap(),mremap() and munmap() doesn't do page_align()
which is incorrect and not consist with mmu arch.
This patch fix it.
Signed-off-by: Bob Liu <lliubbo@xxxxxxxxx>
---
mm/nommu.c | 24 ++++++++++++++----------
1 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/mm/nommu.c b/mm/nommu.c
index c4c542c..3febfd9 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1133,7 +1133,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
unsigned long capabilities)
{
struct page *pages;
- unsigned long total, point, n, rlen;
+ unsigned long total, point, n;
void *base;
int ret, order;
@@ -1157,13 +1157,12 @@ static int do_mmap_private(struct vm_area_struct *vma,
* make a private copy of the data and map that instead */
}
- rlen = PAGE_ALIGN(len);
/* allocate some memory to hold the mapping
* - note that this may not return a page-aligned address if the object
* we're allocating is smaller than a page
*/
- order = get_order(rlen);
+ order = get_order(len);
kdebug("alloc order %d for %lx", order, len);
pages = alloc_pages(GFP_KERNEL, order);
@@ -1173,7 +1172,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
total = 1 << order;
atomic_long_add(total, &mmap_pages_allocated);
- point = rlen >> PAGE_SHIFT;
+ point = len >> PAGE_SHIFT;
/* we allocated a power-of-2 sized page set, so we may want to trim off
* the excess */
@@ -1195,7 +1194,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
base = page_address(pages);
region->vm_flags = vma->vm_flags |= VM_MAPPED_COPY;
region->vm_start = (unsigned long) base;
- region->vm_end = region->vm_start + rlen;
+ region->vm_end = region->vm_start + len;
region->vm_top = region->vm_start + (total << PAGE_SHIFT);
vma->vm_start = region->vm_start;
@@ -1211,15 +1210,15 @@ static int do_mmap_private(struct vm_area_struct *vma,
old_fs = get_fs();
set_fs(KERNEL_DS);
- ret = vma->vm_file->f_op->read(vma->vm_file, base, rlen, &fpos);
+ ret = vma->vm_file->f_op->read(vma->vm_file, base, len, &fpos);
set_fs(old_fs);
if (ret < 0)
goto error_free;
/* clear the last little bit */
- if (ret < rlen)
- memset(base + ret, 0, rlen - ret);
+ if (ret < len)
+ memset(base + ret, 0, len - ret);
}
@@ -1268,6 +1267,7 @@ unsigned long do_mmap_pgoff(struct file *file,
/* we ignore the address hint */
addr = 0;
+ len = PAGE_ALIGN(len);
/* we've determined that we can make the mapping, now translate what we
* now know into VMA flags */
@@ -1645,14 +1645,16 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len)
{
struct vm_area_struct *vma;
struct rb_node *rb;
- unsigned long end = start + len;
+ unsigned long end;
int ret;
kenter(",%lx,%zx", start, len);
- if (len == 0)
+ if ((len = PAGE_ALIGN(len)) == 0)
return -EINVAL;
+ end = start + len;
+
/* find the first potentially overlapping VMA */
vma = find_vma(mm, start);
if (!vma) {
@@ -1773,6 +1775,8 @@ unsigned long do_mremap(unsigned long addr,
struct vm_area_struct *vma;
/* insanity checks first */
+ old_len = PAGE_ALIGN(old_len);
+ new_len = PAGE_ALIGN(new_len);
if (old_len == 0 || new_len == 0)
return (unsigned long) -EINVAL;
--
1.6.3.3
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