Commit 06ecc0db authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds

[PATCH] rmap 35 mmap.c cleanups

From: Hugh Dickins <hugh@veritas.com>

Before some real vma_merge work in mmap.c in the next patch, a patch of
miscellaneous cleanups to cut down the noise:

- remove rb_parent arg from vma_merge: mm->mmap can do that case
- scatter pgoff_t around to ingratiate myself with the boss
- reorder is_mergeable_vma tests, vm_ops->close is least likely
- can_vma_merge_before take combined pgoff+pglen arg (from Andrea)
- rearrange do_mmap_pgoff's ever-confusing anonymous flags switch
- comment do_mmap_pgoff's mysterious (vm_flags & VM_SHARED) test
- fix ISO C90 warning on browse_rb if building with DEBUG_MM_RB
- stop that long MNT_NOEXEC line wrapping

Yes, buried in amidst these is indeed one pgoff replaced by "next->vm_pgoff -
pglen" (reverting a mod of mine which took pgoff supplied by user too
seriously in the anon case), and another pgoff replaced by 0 (reverting
anon_vma mod which crept in with NUMA API): neither of them really matters,
except perhaps in /proc/pid/maps.
parent 4877b14f
......@@ -612,7 +612,7 @@ extern void insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
struct rb_node **, struct rb_node *);
extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
unsigned long addr, unsigned long len, unsigned long pgoff);
unsigned long addr, unsigned long len, pgoff_t pgoff);
extern void exit_mmap(struct mm_struct *);
extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
......
......@@ -154,10 +154,10 @@ asmlinkage unsigned long sys_brk(unsigned long brk)
}
#ifdef DEBUG_MM_RB
static int browse_rb(struct rb_root *root) {
int i, j;
static int browse_rb(struct rb_root *root)
{
int i = 0, j;
struct rb_node *nd, *pn = NULL;
i = 0;
unsigned long prev = 0, pend = 0;
for (nd = rb_first(root); nd; nd = rb_next(nd)) {
......@@ -181,10 +181,11 @@ static int browse_rb(struct rb_root *root) {
return i;
}
void validate_mm(struct mm_struct * mm) {
void validate_mm(struct mm_struct *mm)
{
int bug = 0;
int i = 0;
struct vm_area_struct * tmp = mm->mmap;
struct vm_area_struct *tmp = mm->mmap;
while (tmp) {
tmp = tmp->vm_next;
i++;
......@@ -407,17 +408,17 @@ void vma_adjust(struct vm_area_struct *vma, unsigned long start,
static inline int is_mergeable_vma(struct vm_area_struct *vma,
struct file *file, unsigned long vm_flags)
{
if (vma->vm_ops && vma->vm_ops->close)
if (vma->vm_flags != vm_flags)
return 0;
if (vma->vm_file != file)
return 0;
if (vma->vm_flags != vm_flags)
if (vma->vm_ops && vma->vm_ops->close)
return 0;
return 1;
}
/*
* Return true if we can merge this (vm_flags,file,vm_pgoff,size)
* Return true if we can merge this (vm_flags,file,vm_pgoff)
* in front of (at a lower virtual address and file offset than) the vma.
*
* We don't check here for the merged mmap wrapping around the end of pagecache
......@@ -426,12 +427,12 @@ static inline int is_mergeable_vma(struct vm_area_struct *vma,
*/
static int
can_vma_merge_before(struct vm_area_struct *vma, unsigned long vm_flags,
struct file *file, unsigned long vm_pgoff, unsigned long size)
struct file *file, pgoff_t vm_pgoff)
{
if (is_mergeable_vma(vma, file, vm_flags)) {
if (!file)
return 1; /* anon mapping */
if (vma->vm_pgoff == vm_pgoff + size)
if (vma->vm_pgoff == vm_pgoff)
return 1;
}
return 0;
......@@ -443,16 +444,16 @@ can_vma_merge_before(struct vm_area_struct *vma, unsigned long vm_flags,
*/
static int
can_vma_merge_after(struct vm_area_struct *vma, unsigned long vm_flags,
struct file *file, unsigned long vm_pgoff)
struct file *file, pgoff_t vm_pgoff)
{
if (is_mergeable_vma(vma, file, vm_flags)) {
unsigned long vma_size;
pgoff_t vm_pglen;
if (!file)
return 1; /* anon mapping */
vma_size = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
if (vma->vm_pgoff + vma_size == vm_pgoff)
vm_pglen = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
if (vma->vm_pgoff + vm_pglen == vm_pgoff)
return 1;
}
return 0;
......@@ -464,12 +465,12 @@ can_vma_merge_after(struct vm_area_struct *vma, unsigned long vm_flags,
* both (it neatly fills a hole).
*/
static struct vm_area_struct *vma_merge(struct mm_struct *mm,
struct vm_area_struct *prev,
struct rb_node *rb_parent, unsigned long addr,
struct vm_area_struct *prev, unsigned long addr,
unsigned long end, unsigned long vm_flags,
struct file *file, unsigned long pgoff,
struct file *file, pgoff_t pgoff,
struct mempolicy *policy)
{
pgoff_t pglen = (end - addr) >> PAGE_SHIFT;
struct vm_area_struct *next;
/*
......@@ -480,7 +481,7 @@ static struct vm_area_struct *vma_merge(struct mm_struct *mm,
return NULL;
if (!prev) {
next = rb_entry(rb_parent, struct vm_area_struct, vm_rb);
next = mm->mmap;
goto merge_next;
}
next = prev->vm_next;
......@@ -497,7 +498,7 @@ static struct vm_area_struct *vma_merge(struct mm_struct *mm,
if (next && end == next->vm_start &&
mpol_equal(policy, vma_policy(next)) &&
can_vma_merge_before(next, vm_flags, file,
pgoff, (end - addr) >> PAGE_SHIFT)) {
pgoff+pglen)) {
vma_adjust(prev, prev->vm_start,
next->vm_end, prev->vm_pgoff, next);
if (file)
......@@ -511,17 +512,18 @@ static struct vm_area_struct *vma_merge(struct mm_struct *mm,
return prev;
}
merge_next:
/*
* Can this new request be merged in front of next?
*/
if (next) {
merge_next:
if (end == next->vm_start &&
mpol_equal(policy, vma_policy(next)) &&
can_vma_merge_before(next, vm_flags, file,
pgoff, (end - addr) >> PAGE_SHIFT)) {
vma_adjust(next, addr,
next->vm_end, pgoff, NULL);
pgoff+pglen)) {
vma_adjust(next, addr, next->vm_end,
next->vm_pgoff - pglen, NULL);
return next;
}
}
......@@ -554,7 +556,8 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
if (!file->f_op || !file->f_op->mmap)
return -ENODEV;
if ((prot & PROT_EXEC) && (file->f_vfsmnt->mnt_flags & MNT_NOEXEC))
if ((prot & PROT_EXEC) &&
(file->f_vfsmnt->mnt_flags & MNT_NOEXEC))
return -EPERM;
}
......@@ -636,15 +639,14 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
return -EINVAL;
}
} else {
vm_flags |= VM_SHARED | VM_MAYSHARE;
switch (flags & MAP_TYPE) {
default:
return -EINVAL;
case MAP_PRIVATE:
vm_flags &= ~(VM_SHARED | VM_MAYSHARE);
/* fall through */
case MAP_SHARED:
vm_flags |= VM_SHARED | VM_MAYSHARE;
break;
case MAP_PRIVATE:
break;
default:
return -EINVAL;
}
}
......@@ -683,11 +685,14 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
}
}
/* Can we just expand an old anonymous mapping? */
if (!file && !(vm_flags & VM_SHARED) && rb_parent)
if (vma_merge(mm, prev, rb_parent, addr, addr + len,
vm_flags, NULL, pgoff, NULL))
goto out;
/*
* Can we just expand an old private anonymous mapping?
* The VM_SHARED test is necessary because shmem_zero_setup
* will create the file object for a shared anonymous map below.
*/
if (!file && !(vm_flags & VM_SHARED) &&
vma_merge(mm, prev, addr, addr + len, vm_flags, NULL, 0, NULL))
goto out;
/*
* Determine the object being mapped and call the appropriate
......@@ -744,10 +749,8 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
*/
addr = vma->vm_start;
if (!file || !rb_parent || !vma_merge(mm, prev, rb_parent, addr,
vma->vm_end,
vma->vm_flags, file, pgoff,
vma_policy(vma))) {
if (!file || !vma_merge(mm, prev, addr, vma->vm_end,
vma->vm_flags, file, pgoff, vma_policy(vma))) {
vma_link(mm, vma, prev, rb_link, rb_parent);
if (correct_wcount)
atomic_inc(&inode->i_writecount);
......@@ -1430,9 +1433,8 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
/* Can we just expand an old anonymous mapping? */
if (rb_parent && vma_merge(mm, prev, rb_parent, addr, addr + len,
flags, NULL, 0, NULL))
/* Can we just expand an old private anonymous mapping? */
if (vma_merge(mm, prev, addr, addr + len, flags, NULL, 0, NULL))
goto out;
/*
......@@ -1525,7 +1527,7 @@ void insert_vm_struct(struct mm_struct * mm, struct vm_area_struct * vma)
* prior to moving page table entries, to effect an mremap move.
*/
struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
unsigned long addr, unsigned long len, unsigned long pgoff)
unsigned long addr, unsigned long len, pgoff_t pgoff)
{
struct vm_area_struct *vma = *vmap;
unsigned long vma_start = vma->vm_start;
......@@ -1535,7 +1537,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
struct mempolicy *pol;
find_vma_prepare(mm, addr, &prev, &rb_link, &rb_parent);
new_vma = vma_merge(mm, prev, rb_parent, addr, addr + len,
new_vma = vma_merge(mm, prev, addr, addr + len,
vma->vm_flags, vma->vm_file, pgoff, vma_policy(vma));
if (new_vma) {
/*
......
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