24 static struct file *ovl_open_realfile(const struct file *file,  in ovl_open_realfile()  argument
27 	struct inode *inode = file_inode(file);  in ovl_open_realfile()
28 	struct file *realfile;  in ovl_open_realfile()
30 	int flags = file->f_flags | O_NOATIME | FMODE_NONOTIFY;  in ovl_open_realfile()
33 	realfile = open_with_fake_path(&file->f_path, flags, realinode,  in ovl_open_realfile()
38 		 file, file, ovl_whatisit(inode, realinode), file->f_flags,  in ovl_open_realfile()
46 static int ovl_change_flags(struct file *file, unsigned int flags)  in ovl_change_flags()  argument
48 	struct inode *inode = file_inode(file);  in ovl_change_flags()
55 	if (WARN_ON((file->f_flags ^ flags) & ~OVL_SETFL_MASK))  in ovl_change_flags()
60 	if (((flags ^ file->f_flags) & O_APPEND) && IS_APPEND(inode))  in ovl_change_flags()
64 		if (!file->f_mapping->a_ops ||  in ovl_change_flags()
65 		    !file->f_mapping->a_ops->direct_IO)  in ovl_change_flags()
69 	if (file->f_op->check_flags) {  in ovl_change_flags()
70 		err = file->f_op->check_flags(flags);  in ovl_change_flags()
75 	spin_lock(&file->f_lock);  in ovl_change_flags()
76 	file->f_flags = (file->f_flags & ~OVL_SETFL_MASK) | flags;  in ovl_change_flags()
77 	spin_unlock(&file->f_lock);  in ovl_change_flags()
82 static int ovl_real_fdget_meta(const struct file *file, struct fd *real,  in ovl_real_fdget_meta()  argument
85 	struct inode *inode = file_inode(file);  in ovl_real_fdget_meta()
89 	real->file = file->private_data;  in ovl_real_fdget_meta()
97 	if (unlikely(file_inode(real->file) != realinode)) {  in ovl_real_fdget_meta()
99 		real->file = ovl_open_realfile(file, realinode);  in ovl_real_fdget_meta()
101 		return PTR_ERR_OR_ZERO(real->file);  in ovl_real_fdget_meta()
105 	if (unlikely((file->f_flags ^ real->file->f_flags) & ~O_NOATIME))  in ovl_real_fdget_meta()
106 		return ovl_change_flags(real->file, file->f_flags);  in ovl_real_fdget_meta()
111 static int ovl_real_fdget(const struct file *file, struct fd *real)  in ovl_real_fdget()  argument
113 	return ovl_real_fdget_meta(file, real, false);  in ovl_real_fdget()
116 static int ovl_open(struct inode *inode, struct file *file)  in ovl_open()  argument
118 	struct file *realfile;  in ovl_open()
121 	err = ovl_maybe_copy_up(file_dentry(file), file->f_flags);  in ovl_open()
126 	file->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);  in ovl_open()
128 	realfile = ovl_open_realfile(file, ovl_inode_realdata(inode));  in ovl_open()
132 	file->private_data = realfile;  in ovl_open()
137 static int ovl_release(struct inode *inode, struct file *file)  in ovl_release()  argument
139 	fput(file->private_data);  in ovl_release()
144 static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)  in ovl_llseek()  argument
146 	struct inode *inode = file_inode(file);  in ovl_llseek()
157 			return file->f_pos;  in ovl_llseek()
160 			return vfs_setpos(file, 0, 0);  in ovl_llseek()
163 	ret = ovl_real_fdget(file, &real);  in ovl_llseek()
175 	real.file->f_pos = file->f_pos;  in ovl_llseek()
178 	ret = vfs_llseek(real.file, offset, whence);  in ovl_llseek()
181 	file->f_pos = real.file->f_pos;  in ovl_llseek()
189 static void ovl_file_accessed(struct file *file)  in ovl_file_accessed()  argument
193 	if (file->f_flags & O_NOATIME)  in ovl_file_accessed()
196 	inode = file_inode(file);  in ovl_file_accessed()
208 	touch_atime(&file->f_path);  in ovl_file_accessed()
230 	struct file *file = iocb->ki_filp;  in ovl_read_iter()  local
238 	ret = ovl_real_fdget(file, &real);  in ovl_read_iter()
242 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_read_iter()
243 	ret = vfs_iter_read(real.file, iter, &iocb->ki_pos,  in ovl_read_iter()
245 	ovl_revert_creds(file_inode(file)->i_sb, old_cred);  in ovl_read_iter()
247 	ovl_file_accessed(file);  in ovl_read_iter()
256 	struct file *file = iocb->ki_filp;  in ovl_write_iter()  local
257 	struct inode *inode = file_inode(file);  in ovl_write_iter()
268 	ret = file_remove_privs(file);  in ovl_write_iter()
272 	ret = ovl_real_fdget(file, &real);  in ovl_write_iter()
276 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_write_iter()
277 	file_start_write(real.file);  in ovl_write_iter()
278 	ret = vfs_iter_write(real.file, iter, &iocb->ki_pos,  in ovl_write_iter()
280 	file_end_write(real.file);  in ovl_write_iter()
281 	ovl_revert_creds(file_inode(file)->i_sb, old_cred);  in ovl_write_iter()
294 static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)  in ovl_fsync()  argument
300 	ret = ovl_real_fdget_meta(file, &real, !datasync);  in ovl_fsync()
305 	if (file_inode(real.file) == ovl_inode_upper(file_inode(file))) {  in ovl_fsync()
306 		old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fsync()
307 		ret = vfs_fsync_range(real.file, start, end, datasync);  in ovl_fsync()
308 		ovl_revert_creds(file_inode(file)->i_sb, old_cred);  in ovl_fsync()
316 static int ovl_mmap(struct file *file, struct vm_area_struct *vma)  in ovl_mmap()  argument
318 	struct file *realfile = file->private_data;  in ovl_mmap()
325 	if (WARN_ON(file != vma->vm_file))  in ovl_mmap()
330 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_mmap()
332 	ovl_revert_creds(file_inode(file)->i_sb, old_cred);  in ovl_mmap()
339 		fput(file);  in ovl_mmap()
342 	ovl_file_accessed(file);  in ovl_mmap()
347 static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len)  in ovl_fallocate()  argument
349 	struct inode *inode = file_inode(file);  in ovl_fallocate()
354 	ret = ovl_real_fdget(file, &real);  in ovl_fallocate()
358 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fallocate()
359 	ret = vfs_fallocate(real.file, mode, offset, len);  in ovl_fallocate()
360 	ovl_revert_creds(file_inode(file)->i_sb, old_cred);  in ovl_fallocate()
370 static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice)  in ovl_fadvise()  argument
376 	ret = ovl_real_fdget(file, &real);  in ovl_fadvise()
380 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fadvise()
381 	ret = vfs_fadvise(real.file, offset, len, advice);  in ovl_fadvise()
382 	ovl_revert_creds(file_inode(file)->i_sb, old_cred);  in ovl_fadvise()
389 static long ovl_real_ioctl(struct file *file, unsigned int cmd,  in ovl_real_ioctl()  argument
396 	ret = ovl_real_fdget(file, &real);  in ovl_real_ioctl()
400 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_real_ioctl()
401 	ret = vfs_ioctl(real.file, cmd, arg);  in ovl_real_ioctl()
402 	ovl_revert_creds(file_inode(file)->i_sb, old_cred);  in ovl_real_ioctl()
409 static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,  in ovl_ioctl_set_flags()  argument
413 	struct inode *inode = file_inode(file);  in ovl_ioctl_set_flags()
419 	ret = mnt_want_write_file(file);  in ovl_ioctl_set_flags()
432 	ret = ovl_maybe_copy_up(file_dentry(file), O_WRONLY);  in ovl_ioctl_set_flags()
436 	ret = ovl_real_ioctl(file, cmd, arg);  in ovl_ioctl_set_flags()
442 	mnt_drop_write_file(file);  in ovl_ioctl_set_flags()
464 static long ovl_ioctl_set_fsflags(struct file *file, unsigned int cmd,  in ovl_ioctl_set_fsflags()  argument
472 	return ovl_ioctl_set_flags(file, cmd, arg,  in ovl_ioctl_set_fsflags()
492 static long ovl_ioctl_set_fsxflags(struct file *file, unsigned int cmd,  in ovl_ioctl_set_fsxflags()  argument
501 	return ovl_ioctl_set_flags(file, cmd, arg,  in ovl_ioctl_set_fsxflags()
505 static long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)  in ovl_ioctl()  argument
512 		ret = ovl_real_ioctl(file, cmd, arg);  in ovl_ioctl()
516 		ret = ovl_ioctl_set_fsflags(file, cmd, arg);  in ovl_ioctl()
520 		ret = ovl_ioctl_set_fsxflags(file, cmd, arg);  in ovl_ioctl()
530 static long ovl_compat_ioctl(struct file *file, unsigned int cmd,  in ovl_compat_ioctl()  argument
546 	return ovl_ioctl(file, cmd, arg);  in ovl_compat_ioctl()
555 static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,  in ovl_copyfile()
556 			    struct file *file_out, loff_t pos_out,  in ovl_copyfile()
577 		ret = vfs_copy_file_range(real_in.file, pos_in,  in ovl_copyfile()
578 					  real_out.file, pos_out, len, flags);  in ovl_copyfile()
582 		ret = vfs_clone_file_range(real_in.file, pos_in,  in ovl_copyfile()
583 					   real_out.file, pos_out, len, flags);  in ovl_copyfile()
587 		ret = vfs_dedupe_file_range_one(real_in.file, pos_in,  in ovl_copyfile()
588 						real_out.file, pos_out, len,  in ovl_copyfile()
603 static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in,  in ovl_copy_file_range()
604 				   struct file *file_out, loff_t pos_out,  in ovl_copy_file_range()
611 static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in,  in ovl_remap_file_range()
612 				   struct file *file_out, loff_t pos_out,  in ovl_remap_file_range()