7 #include <linux/file.h>
39 static struct file *ovl_open_realfile(const struct file *file,  in ovl_open_realfile()  argument
42 	struct inode *inode = file_inode(file);  in ovl_open_realfile()
43 	struct file *realfile;  in ovl_open_realfile()
45 	int flags = file->f_flags | OVL_OPEN_FLAGS;  in ovl_open_realfile()
59 		realfile = open_with_fake_path(&file->f_path, flags, realinode,  in ovl_open_realfile()
65 		 file, file, ovl_whatisit(inode, realinode), file->f_flags,  in ovl_open_realfile()
73 static int ovl_change_flags(struct file *file, unsigned int flags)  in ovl_change_flags()  argument
75 	struct inode *inode = file_inode(file);  in ovl_change_flags()
81 	if (WARN_ON((file->f_flags ^ flags) & ~OVL_SETFL_MASK))  in ovl_change_flags()
86 	if (((flags ^ file->f_flags) & O_APPEND) && IS_APPEND(inode))  in ovl_change_flags()
90 		if (!file->f_mapping->a_ops ||  in ovl_change_flags()
91 		    !file->f_mapping->a_ops->direct_IO)  in ovl_change_flags()
95 	if (file->f_op->check_flags) {  in ovl_change_flags()
96 		err = file->f_op->check_flags(flags);  in ovl_change_flags()
101 	spin_lock(&file->f_lock);  in ovl_change_flags()
102 	file->f_flags = (file->f_flags & ~OVL_SETFL_MASK) | flags;  in ovl_change_flags()
103 	spin_unlock(&file->f_lock);  in ovl_change_flags()
108 static int ovl_real_fdget_meta(const struct file *file, struct fd *real,  in ovl_real_fdget_meta()  argument
111 	struct inode *inode = file_inode(file);  in ovl_real_fdget_meta()
115 	real->file = file->private_data;  in ovl_real_fdget_meta()
123 	if (unlikely(file_inode(real->file) != realinode)) {  in ovl_real_fdget_meta()
125 		real->file = ovl_open_realfile(file, realinode);  in ovl_real_fdget_meta()
127 		return PTR_ERR_OR_ZERO(real->file);  in ovl_real_fdget_meta()
131 	if (unlikely((file->f_flags ^ real->file->f_flags) & ~OVL_OPEN_FLAGS))  in ovl_real_fdget_meta()
132 		return ovl_change_flags(real->file, file->f_flags);  in ovl_real_fdget_meta()
137 static int ovl_real_fdget(const struct file *file, struct fd *real)  in ovl_real_fdget()  argument
139 	if (d_is_dir(file_dentry(file))) {  in ovl_real_fdget()
141 		real->file = ovl_dir_real_file(file, false);  in ovl_real_fdget()
143 		return PTR_ERR_OR_ZERO(real->file);  in ovl_real_fdget()
146 	return ovl_real_fdget_meta(file, real, false);  in ovl_real_fdget()
149 static int ovl_open(struct inode *inode, struct file *file)  in ovl_open()  argument
151 	struct file *realfile;  in ovl_open()
154 	err = ovl_maybe_copy_up(file_dentry(file), file->f_flags);  in ovl_open()
159 	file->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);  in ovl_open()
161 	realfile = ovl_open_realfile(file, ovl_inode_realdata(inode));  in ovl_open()
165 	file->private_data = realfile;  in ovl_open()
170 static int ovl_release(struct inode *inode, struct file *file)  in ovl_release()  argument
172 	fput(file->private_data);  in ovl_release()
177 static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)  in ovl_llseek()  argument
179 	struct inode *inode = file_inode(file);  in ovl_llseek()
190 			return file->f_pos;  in ovl_llseek()
193 			return vfs_setpos(file, 0, 0);  in ovl_llseek()
196 	ret = ovl_real_fdget(file, &real);  in ovl_llseek()
201 	 * Overlay file f_pos is the master copy that is preserved  in ovl_llseek()
205 	 * files, so we use the real file to perform seeks.  in ovl_llseek()
208 	real.file->f_pos = file->f_pos;  in ovl_llseek()
211 	ret = vfs_llseek(real.file, offset, whence);  in ovl_llseek()
214 	file->f_pos = real.file->f_pos;  in ovl_llseek()
222 static void ovl_file_accessed(struct file *file)  in ovl_file_accessed()  argument
226 	if (file->f_flags & O_NOATIME)  in ovl_file_accessed()
229 	inode = file_inode(file);  in ovl_file_accessed()
241 	touch_atime(&file->f_path);  in ovl_file_accessed()
299 	struct file *file = iocb->ki_filp;  in ovl_read_iter()  local
307 	ret = ovl_real_fdget(file, &real);  in ovl_read_iter()
313 	    (!real.file->f_mapping->a_ops ||  in ovl_read_iter()
314 	     !real.file->f_mapping->a_ops->direct_IO))  in ovl_read_iter()
317 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_read_iter()
319 		ret = vfs_iter_read(real.file, iter, &iocb->ki_pos,  in ovl_read_iter()
331 		kiocb_clone(&aio_req->iocb, iocb, get_file(real.file));  in ovl_read_iter()
334 		ret = vfs_iocb_iter_read(real.file, &aio_req->iocb, iter);  in ovl_read_iter()
341 	ovl_file_accessed(file);  in ovl_read_iter()
350 	struct file *file = iocb->ki_filp;  in ovl_write_iter()  local
351 	struct inode *inode = file_inode(file);  in ovl_write_iter()
363 	ret = file_remove_privs(file);  in ovl_write_iter()
367 	ret = ovl_real_fdget(file, &real);  in ovl_write_iter()
373 	    (!real.file->f_mapping->a_ops ||  in ovl_write_iter()
374 	     !real.file->f_mapping->a_ops->direct_IO))  in ovl_write_iter()
380 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_write_iter()
382 		file_start_write(real.file);  in ovl_write_iter()
383 		ret = vfs_iter_write(real.file, iter, &iocb->ki_pos,  in ovl_write_iter()
385 		file_end_write(real.file);  in ovl_write_iter()
396 		file_start_write(real.file);  in ovl_write_iter()
398 		__sb_writers_release(file_inode(real.file)->i_sb,  in ovl_write_iter()
402 		kiocb_clone(&aio_req->iocb, iocb, get_file(real.file));  in ovl_write_iter()
406 		ret = vfs_iocb_iter_write(real.file, &aio_req->iocb, iter);  in ovl_write_iter()
425  * and file_start_write(real.file) in ovl_write_iter().
428  * the real file.
430 static ssize_t ovl_splice_write(struct pipe_inode_info *pipe, struct file *out,  in ovl_splice_write()
451 	file_start_write(real.file);  in ovl_splice_write()
453 	ret = iter_file_splice_write(pipe, real.file, ppos, len, flags);  in ovl_splice_write()
455 	file_end_write(real.file);  in ovl_splice_write()
467 static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)  in ovl_fsync()  argument
473 	ret = ovl_sync_status(OVL_FS(file_inode(file)->i_sb));  in ovl_fsync()
477 	ret = ovl_real_fdget_meta(file, &real, !datasync);  in ovl_fsync()
481 	/* Don't sync lower file for fear of receiving EROFS error */  in ovl_fsync()
482 	if (file_inode(real.file) == ovl_inode_upper(file_inode(file))) {  in ovl_fsync()
483 		old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fsync()
484 		ret = vfs_fsync_range(real.file, start, end, datasync);  in ovl_fsync()
493 static int ovl_mmap(struct file *file, struct vm_area_struct *vma)  in ovl_mmap()  argument
495 	struct file *realfile = file->private_data;  in ovl_mmap()
502 	if (WARN_ON(file != vma->vm_file))  in ovl_mmap()
507 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_mmap()
516 		fput(file);  in ovl_mmap()
519 	ovl_file_accessed(file);  in ovl_mmap()
524 static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len)  in ovl_fallocate()  argument
526 	struct inode *inode = file_inode(file);  in ovl_fallocate()
534 	ret = file_remove_privs(file);  in ovl_fallocate()
538 	ret = ovl_real_fdget(file, &real);  in ovl_fallocate()
542 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fallocate()
543 	ret = vfs_fallocate(real.file, mode, offset, len);  in ovl_fallocate()
557 static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice)  in ovl_fadvise()  argument
563 	ret = ovl_real_fdget(file, &real);  in ovl_fadvise()
567 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fadvise()
568 	ret = vfs_fadvise(real.file, offset, len, advice);  in ovl_fadvise()
576 static long ovl_real_ioctl(struct file *file, unsigned int cmd,  in ovl_real_ioctl()  argument
582 	ret = ovl_real_fdget(file, &real);  in ovl_real_ioctl()
586 	ret = security_file_ioctl(real.file, cmd, arg);  in ovl_real_ioctl()
592 		ret = vfs_ioctl(real.file, cmd, arg);  in ovl_real_ioctl()
600 static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,  in ovl_ioctl_set_flags()  argument
604 	struct inode *inode = file_inode(file);  in ovl_ioctl_set_flags()
609 	ret = mnt_want_write_file(file);  in ovl_ioctl_set_flags()
624 	ret = ovl_maybe_copy_up(file_dentry(file), O_WRONLY);  in ovl_ioctl_set_flags()
628 	ret = ovl_real_ioctl(file, cmd, arg);  in ovl_ioctl_set_flags()
634 	mnt_drop_write_file(file);  in ovl_ioctl_set_flags()
640 long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)  in ovl_ioctl()  argument
647 		ret = ovl_real_ioctl(file, cmd, arg);  in ovl_ioctl()
652 		ret = ovl_ioctl_set_flags(file, cmd, arg);  in ovl_ioctl()
663 long ovl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)  in ovl_compat_ioctl()  argument
678 	return ovl_ioctl(file, cmd, arg);  in ovl_compat_ioctl()
688 static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,  in ovl_copyfile()
689 			    struct file *file_out, loff_t pos_out,  in ovl_copyfile()
719 		ret = vfs_copy_file_range(real_in.file, pos_in,  in ovl_copyfile()
720 					  real_out.file, pos_out, len, flags);  in ovl_copyfile()
724 		ret = vfs_clone_file_range(real_in.file, pos_in,  in ovl_copyfile()
725 					   real_out.file, pos_out, len, flags);  in ovl_copyfile()
729 		ret = vfs_dedupe_file_range_one(real_in.file, pos_in,  in ovl_copyfile()
730 						real_out.file, pos_out, len,  in ovl_copyfile()
748 static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in,  in ovl_copy_file_range()
749 				   struct file *file_out, loff_t pos_out,  in ovl_copy_file_range()
756 static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in,  in ovl_remap_file_range()
757 				   struct file *file_out, loff_t pos_out,  in ovl_remap_file_range()