Merge branch 'work.open3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs open-related updates from Al Viro:

 - "do we need fput() or put_filp()" rules are gone - it's always fput()
   now. We keep track of that state where it belongs - in ->f_mode.

 - int *opened mess killed - in finish_open(), in ->atomic_open()
   instances and in fs/namei.c code around do_last()/lookup_open()/atomic_open().

 - alloc_file() wrappers with saner calling conventions are introduced
   (alloc_file_clone() and alloc_file_pseudo()); callers converted, with
   much simplification.

 - while we are at it, saner calling conventions for path_init() and
   link_path_walk(), simplifying things inside fs/namei.c (both on
   open-related paths and elsewhere).

* 'work.open3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
  few more cleanups of link_path_walk() callers
  allow link_path_walk() to take ERR_PTR()
  make path_init() unconditionally paired with terminate_walk()
  document alloc_file() changes
  make alloc_file() static
  do_shmat(): grab shp->shm_file earlier, switch to alloc_file_clone()
  new helper: alloc_file_clone()
  create_pipe_files(): switch the first allocation to alloc_file_pseudo()
  anon_inode_getfile(): switch to alloc_file_pseudo()
  hugetlb_file_setup(): switch to alloc_file_pseudo()
  ocxlflash_getfile(): switch to alloc_file_pseudo()
  cxl_getfile(): switch to alloc_file_pseudo()
  ... and switch shmem_file_setup() to alloc_file_pseudo()
  __shmem_file_setup(): reorder allocations
  new wrapper: alloc_file_pseudo()
  kill FILE_{CREATED,OPENED}
  switch atomic_open() and lookup_open() to returning 0 in all success cases
  document ->atomic_open() changes
  ->atomic_open(): return 0 in all success cases
  get rid of 'opened' in path_openat() and the helpers downstream
  ...

fs/hugetlbfs/inode.c

@@ -1310,10 +1310,6 @@ static int get_hstate_idx(int page_size_log)
 	return h - hstates;
 }
 
-static const struct dentry_operations anon_ops = {
-	.d_dname = simple_dname
-};
-
 /*
  * Note that size should be aligned to proper hugepage size in caller side,
  * otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
@@ -1322,19 +1318,18 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
 				vm_flags_t acctflag, struct user_struct **user,
 				int creat_flags, int page_size_log)
 {
-	struct file *file = ERR_PTR(-ENOMEM);
 	struct inode *inode;
-	struct path path;
-	struct super_block *sb;
-	struct qstr quick_string;
+	struct vfsmount *mnt;
 	int hstate_idx;
+	struct file *file;
 
 	hstate_idx = get_hstate_idx(page_size_log);
 	if (hstate_idx < 0)
 		return ERR_PTR(-ENODEV);
 
 	*user = NULL;
-	if (!hugetlbfs_vfsmount[hstate_idx])
+	mnt = hugetlbfs_vfsmount[hstate_idx];
+	if (!mnt)
 		return ERR_PTR(-ENOENT);
 
 	if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
@@ -1350,45 +1345,28 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
 		}
 	}
 
-	sb = hugetlbfs_vfsmount[hstate_idx]->mnt_sb;
-	quick_string.name = name;
-	quick_string.len = strlen(quick_string.name);
-	quick_string.hash = 0;
-	path.dentry = d_alloc_pseudo(sb, &quick_string);
-	if (!path.dentry)
-		goto out_shm_unlock;
-
-	d_set_d_op(path.dentry, &anon_ops);
-	path.mnt = mntget(hugetlbfs_vfsmount[hstate_idx]);
 	file = ERR_PTR(-ENOSPC);
-	inode = hugetlbfs_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0);
+	inode = hugetlbfs_get_inode(mnt->mnt_sb, NULL, S_IFREG | S_IRWXUGO, 0);
 	if (!inode)
-		goto out_dentry;
+		goto out;
 	if (creat_flags == HUGETLB_SHMFS_INODE)
 		inode->i_flags |= S_PRIVATE;
 
-	file = ERR_PTR(-ENOMEM);
-	if (hugetlb_reserve_pages(inode, 0,
-			size >> huge_page_shift(hstate_inode(inode)), NULL,
-			acctflag))
-		goto out_inode;
-
-	d_instantiate(path.dentry, inode);
 	inode->i_size = size;
 	clear_nlink(inode);
 
-	file = alloc_file(&path, FMODE_WRITE | FMODE_READ,
-			&hugetlbfs_file_operations);
-	if (IS_ERR(file))
-		goto out_dentry; /* inode is already attached */
+	if (hugetlb_reserve_pages(inode, 0,
+			size >> huge_page_shift(hstate_inode(inode)), NULL,
+			acctflag))
+		file = ERR_PTR(-ENOMEM);
+	else
+		file = alloc_file_pseudo(inode, mnt, name, O_RDWR,
+					&hugetlbfs_file_operations);
+	if (!IS_ERR(file))
+		return file;
 
-	return file;
-
-out_inode:
 	iput(inode);
-out_dentry:
-	path_put(&path);
-out_shm_unlock:
+out:
 	if (*user) {
 		user_shm_unlock(size, *user);
 		*user = NULL;