Merge branch 'master' of /home/davem/src/GIT/linux-2.6/

1 files changed, 117 insertions, 58 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index ee2298936fe6..75557c639ad4 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -265,7 +265,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 	 * segment grow beyond its set limit the in case where the limit is
 	 * not page aligned -Ram Gupta
 	 */
-	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
+	rlim = rlimit(RLIMIT_DATA);
 	if (rlim < RLIM_INFINITY && (brk - mm->start_brk) +
 			(mm->end_data - mm->start_data) > rlim)
 		goto out;
@@ -437,7 +437,6 @@ __vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
 {
 	__vma_link_list(mm, vma, prev, rb_parent);
 	__vma_link_rb(mm, vma, rb_link, rb_parent);
-	__anon_vma_link(vma);
 }
 
 static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -499,7 +498,7 @@ __vma_unlink(struct mm_struct *mm, struct vm_area_struct *vma,
  * are necessary.  The "insert" vma (if any) is to be inserted
  * before we drop the necessary locks.
  */
-void vma_adjust(struct vm_area_struct *vma, unsigned long start,
+int vma_adjust(struct vm_area_struct *vma, unsigned long start,
 	unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert)
 {
 	struct mm_struct *mm = vma->vm_mm;
@@ -542,6 +541,26 @@ again:			remove_next = 1 + (end > next->vm_end);
 		}
 	}
 
+	/*
+	 * When changing only vma->vm_end, we don't really need anon_vma lock.
+	 */
+	if (vma->anon_vma && (insert || importer || start != vma->vm_start))
+		anon_vma = vma->anon_vma;
+	if (anon_vma) {
+		/*
+		 * Easily overlooked: when mprotect shifts the boundary,
+		 * make sure the expanding vma has anon_vma set if the
+		 * shrinking vma had, to cover any anon pages imported.
+		 */
+		if (importer && !importer->anon_vma) {
+			/* Block reverse map lookups until things are set up. */
+			if (anon_vma_clone(importer, vma)) {
+				return -ENOMEM;
+			}
+			importer->anon_vma = anon_vma;
+		}
+	}
+
 	if (file) {
 		mapping = file->f_mapping;
 		if (!(vma->vm_flags & VM_NONLINEAR))
@@ -567,25 +586,6 @@ again:			remove_next = 1 + (end > next->vm_end);
 		}
 	}
 
-	/*
-	 * When changing only vma->vm_end, we don't really need
-	 * anon_vma lock.
-	 */
-	if (vma->anon_vma && (insert || importer || start != vma->vm_start))
-		anon_vma = vma->anon_vma;
-	if (anon_vma) {
-		spin_lock(&anon_vma->lock);
-		/*
-		 * Easily overlooked: when mprotect shifts the boundary,
-		 * make sure the expanding vma has anon_vma set if the
-		 * shrinking vma had, to cover any anon pages imported.
-		 */
-		if (importer && !importer->anon_vma) {
-			importer->anon_vma = anon_vma;
-			__anon_vma_link(importer);
-		}
-	}
-
 	if (root) {
 		flush_dcache_mmap_lock(mapping);
 		vma_prio_tree_remove(vma, root);
@@ -616,8 +616,6 @@ again:			remove_next = 1 + (end > next->vm_end);
 		__vma_unlink(mm, next, vma);
 		if (file)
 			__remove_shared_vm_struct(next, file, mapping);
-		if (next->anon_vma)
-			__anon_vma_merge(vma, next);
 	} else if (insert) {
 		/*
 		 * split_vma has split insert from vma, and needs
@@ -627,8 +625,6 @@ again:			remove_next = 1 + (end > next->vm_end);
 		__insert_vm_struct(mm, insert);
 	}
 
-	if (anon_vma)
-		spin_unlock(&anon_vma->lock);
 	if (mapping)
 		spin_unlock(&mapping->i_mmap_lock);
 
@@ -638,6 +634,8 @@ again:			remove_next = 1 + (end > next->vm_end);
 			if (next->vm_flags & VM_EXECUTABLE)
 				removed_exe_file_vma(mm);
 		}
+		if (next->anon_vma)
+			anon_vma_merge(vma, next);
 		mm->map_count--;
 		mpol_put(vma_policy(next));
 		kmem_cache_free(vm_area_cachep, next);
@@ -653,6 +651,8 @@ again:			remove_next = 1 + (end > next->vm_end);
 	}
 
 	validate_mm(mm);
+
+	return 0;
 }
 
 /*
@@ -759,6 +759,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
 {
 	pgoff_t pglen = (end - addr) >> PAGE_SHIFT;
 	struct vm_area_struct *area, *next;
+	int err;
 
 	/*
 	 * We later require that vma->vm_flags == vm_flags,
@@ -792,11 +793,13 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
 				is_mergeable_anon_vma(prev->anon_vma,
 						      next->anon_vma)) {
 							/* cases 1, 6 */
-			vma_adjust(prev, prev->vm_start,
+			err = vma_adjust(prev, prev->vm_start,
 				next->vm_end, prev->vm_pgoff, NULL);
 		} else					/* cases 2, 5, 7 */
-			vma_adjust(prev, prev->vm_start,
+			err = vma_adjust(prev, prev->vm_start,
 				end, prev->vm_pgoff, NULL);
+		if (err)
+			return NULL;
 		return prev;
 	}
 
@@ -808,11 +811,13 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
 			can_vma_merge_before(next, vm_flags,
 					anon_vma, file, pgoff+pglen)) {
 		if (prev && addr < prev->vm_end)	/* case 4 */
-			vma_adjust(prev, prev->vm_start,
+			err = vma_adjust(prev, prev->vm_start,
 				addr, prev->vm_pgoff, NULL);
 		else					/* cases 3, 8 */
-			vma_adjust(area, addr, next->vm_end,
+			err = vma_adjust(area, addr, next->vm_end,
 				next->vm_pgoff - pglen, NULL);
+		if (err)
+			return NULL;
 		return area;
 	}
 
@@ -967,7 +972,7 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 		unsigned long locked, lock_limit;
 		locked = len >> PAGE_SHIFT;
 		locked += mm->locked_vm;
-		lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+		lock_limit = rlimit(RLIMIT_MEMLOCK);
 		lock_limit >>= PAGE_SHIFT;
 		if (locked > lock_limit && !capable(CAP_IPC_LOCK))
 			return -EAGAIN;
@@ -1083,6 +1088,30 @@ out:
 	return retval;
 }
 
+#ifdef __ARCH_WANT_SYS_OLD_MMAP
+struct mmap_arg_struct {
+	unsigned long addr;
+	unsigned long len;
+	unsigned long prot;
+	unsigned long flags;
+	unsigned long fd;
+	unsigned long offset;
+};
+
+SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg)
+{
+	struct mmap_arg_struct a;
+
+	if (copy_from_user(&a, arg, sizeof(a)))
+		return -EFAULT;
+	if (a.offset & ~PAGE_MASK)
+		return -EINVAL;
+
+	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+			      a.offset >> PAGE_SHIFT);
+}
+#endif /* __ARCH_WANT_SYS_OLD_MMAP */
+
 /*
  * Some shared mappigns will want the pages marked read-only
  * to track write events. If so, we'll downgrade vm_page_prot
@@ -1205,6 +1234,7 @@ munmap_back:
 	vma->vm_flags = vm_flags;
 	vma->vm_page_prot = vm_get_page_prot(vm_flags);
 	vma->vm_pgoff = pgoff;
+	INIT_LIST_HEAD(&vma->anon_vma_chain);
 
 	if (file) {
 		error = -EINVAL;
@@ -1265,13 +1295,8 @@ out:
 	mm->total_vm += len >> PAGE_SHIFT;
 	vm_stat_account(mm, vm_flags, file, len >> PAGE_SHIFT);
 	if (vm_flags & VM_LOCKED) {
-		/*
-		 * makes pages present; downgrades, drops, reacquires mmap_sem
-		 */
-		long nr_pages = mlock_vma_pages_range(vma, addr, addr + len);
-		if (nr_pages < 0)
-			return nr_pages;	/* vma gone! */
-		mm->locked_vm += (len >> PAGE_SHIFT) - nr_pages;
+		if (!mlock_vma_pages_range(vma, addr, addr + len))
+			mm->locked_vm += (len >> PAGE_SHIFT);
 	} else if ((flags & MAP_POPULATE) && !(flags & MAP_NONBLOCK))
 		make_pages_present(addr, addr + len);
 	return addr;
@@ -1599,7 +1624,7 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns
 		return -ENOMEM;
 
 	/* Stack limit test */
-	if (size > rlim[RLIMIT_STACK].rlim_cur)
+	if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur))
 		return -ENOMEM;
 
 	/* mlock limit tests */
@@ -1607,7 +1632,8 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns
 		unsigned long locked;
 		unsigned long limit;
 		locked = mm->locked_vm + grow;
-		limit = rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
+		limit = ACCESS_ONCE(rlim[RLIMIT_MEMLOCK].rlim_cur);
+		limit >>= PAGE_SHIFT;
 		if (locked > limit && !capable(CAP_IPC_LOCK))
 			return -ENOMEM;
 	}
@@ -1754,8 +1780,7 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr)
 	if (!prev || expand_stack(prev, addr))
 		return NULL;
 	if (prev->vm_flags & VM_LOCKED) {
-		if (mlock_vma_pages_range(prev, addr, prev->vm_end) < 0)
-			return NULL;	/* vma gone! */
+		mlock_vma_pages_range(prev, addr, prev->vm_end);
 	}
 	return prev;
 }
@@ -1783,8 +1808,7 @@ find_extend_vma(struct mm_struct * mm, unsigned long addr)
 	if (expand_stack(vma, addr))
 		return NULL;
 	if (vma->vm_flags & VM_LOCKED) {
-		if (mlock_vma_pages_range(vma, addr, start) < 0)
-			return NULL;	/* vma gone! */
+		mlock_vma_pages_range(vma, addr, start);
 	}
 	return vma;
 }
@@ -1871,6 +1895,7 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
 {
 	struct mempolicy *pol;
 	struct vm_area_struct *new;
+	int err = -ENOMEM;
 
 	if (is_vm_hugetlb_page(vma) && (addr &
 					~(huge_page_mask(hstate_vma(vma)))))
@@ -1878,11 +1903,13 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
 
 	new = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
 	if (!new)
-		return -ENOMEM;
+		goto out_err;
 
 	/* most fields are the same, copy all, and then fixup */
 	*new = *vma;
 
+	INIT_LIST_HEAD(&new->anon_vma_chain);
+
 	if (new_below)
 		new->vm_end = addr;
 	else {
@@ -1892,11 +1919,14 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
 
 	pol = mpol_dup(vma_policy(vma));
 	if (IS_ERR(pol)) {
-		kmem_cache_free(vm_area_cachep, new);
-		return PTR_ERR(pol);
+		err = PTR_ERR(pol);
+		goto out_free_vma;
 	}
 	vma_set_policy(new, pol);
 
+	if (anon_vma_clone(new, vma))
+		goto out_free_mpol;
+
 	if (new->vm_file) {
 		get_file(new->vm_file);
 		if (vma->vm_flags & VM_EXECUTABLE)
@@ -1907,12 +1937,28 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
 		new->vm_ops->open(new);
 
 	if (new_below)
-		vma_adjust(vma, addr, vma->vm_end, vma->vm_pgoff +
+		err = vma_adjust(vma, addr, vma->vm_end, vma->vm_pgoff +
 			((addr - new->vm_start) >> PAGE_SHIFT), new);
 	else
-		vma_adjust(vma, vma->vm_start, addr, vma->vm_pgoff, new);
+		err = vma_adjust(vma, vma->vm_start, addr, vma->vm_pgoff, new);
 
-	return 0;
+	/* Success. */
+	if (!err)
+		return 0;
+
+	/* Clean everything up if vma_adjust failed. */
+	new->vm_ops->close(new);
+	if (new->vm_file) {
+		if (vma->vm_flags & VM_EXECUTABLE)
+			removed_exe_file_vma(mm);
+		fput(new->vm_file);
+	}
+ out_free_mpol:
+	mpol_put(pol);
+ out_free_vma:
+	kmem_cache_free(vm_area_cachep, new);
+ out_err:
+	return err;
 }
 
 /*
@@ -2074,7 +2120,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
 		unsigned long locked, lock_limit;
 		locked = len >> PAGE_SHIFT;
 		locked += mm->locked_vm;
-		lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+		lock_limit = rlimit(RLIMIT_MEMLOCK);
 		lock_limit >>= PAGE_SHIFT;
 		if (locked > lock_limit && !capable(CAP_IPC_LOCK))
 			return -EAGAIN;
@@ -2122,6 +2168,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
 		return -ENOMEM;
 	}
 
+	INIT_LIST_HEAD(&vma->anon_vma_chain);
 	vma->vm_mm = mm;
 	vma->vm_start = addr;
 	vma->vm_end = addr + len;
@@ -2258,10 +2305,11 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
 		if (new_vma) {
 			*new_vma = *vma;
 			pol = mpol_dup(vma_policy(vma));
-			if (IS_ERR(pol)) {
-				kmem_cache_free(vm_area_cachep, new_vma);
-				return NULL;
-			}
+			if (IS_ERR(pol))
+				goto out_free_vma;
+			INIT_LIST_HEAD(&new_vma->anon_vma_chain);
+			if (anon_vma_clone(new_vma, vma))
+				goto out_free_mempol;
 			vma_set_policy(new_vma, pol);
 			new_vma->vm_start = addr;
 			new_vma->vm_end = addr + len;
@@ -2277,6 +2325,12 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
 		}
 	}
 	return new_vma;
+
+ out_free_mempol:
+	mpol_put(pol);
+ out_free_vma:
+	kmem_cache_free(vm_area_cachep, new_vma);
+	return NULL;
 }
 
 /*
@@ -2288,7 +2342,7 @@ int may_expand_vm(struct mm_struct *mm, unsigned long npages)
 	unsigned long cur = mm->total_vm;	/* pages */
 	unsigned long lim;
 
-	lim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
+	lim = rlimit(RLIMIT_AS) >> PAGE_SHIFT;
 
 	if (cur + npages > lim)
 		return 0;
@@ -2354,6 +2408,7 @@ int install_special_mapping(struct mm_struct *mm,
 	if (unlikely(vma == NULL))
 		return -ENOMEM;
 
+	INIT_LIST_HEAD(&vma->anon_vma_chain);
 	vma->vm_mm = mm;
 	vma->vm_start = addr;
 	vma->vm_end = addr + len;
@@ -2454,6 +2509,7 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping)
 int mm_take_all_locks(struct mm_struct *mm)
 {
 	struct vm_area_struct *vma;
+	struct anon_vma_chain *avc;
 	int ret = -EINTR;
 
 	BUG_ON(down_read_trylock(&mm->mmap_sem));
@@ -2471,7 +2527,8 @@ int mm_take_all_locks(struct mm_struct *mm)
 		if (signal_pending(current))
 			goto out_unlock;
 		if (vma->anon_vma)
-			vm_lock_anon_vma(mm, vma->anon_vma);
+			list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
+				vm_lock_anon_vma(mm, avc->anon_vma);
 	}
 
 	ret = 0;
@@ -2526,13 +2583,15 @@ static void vm_unlock_mapping(struct address_space *mapping)
 void mm_drop_all_locks(struct mm_struct *mm)
 {
 	struct vm_area_struct *vma;
+	struct anon_vma_chain *avc;
 
 	BUG_ON(down_read_trylock(&mm->mmap_sem));
 	BUG_ON(!mutex_is_locked(&mm_all_locks_mutex));
 
 	for (vma = mm->mmap; vma; vma = vma->vm_next) {
 		if (vma->anon_vma)
-			vm_unlock_anon_vma(vma->anon_vma);
+			list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
+				vm_unlock_anon_vma(avc->anon_vma);
 		if (vma->vm_file && vma->vm_file->f_mapping)
 			vm_unlock_mapping(vma->vm_file->f_mapping);
 	}