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()
60 		realfile = open_with_fake_path(&file->f_path, flags, realinode,  in ovl_open_realfile()
66 		 file, file, ovl_whatisit(inode, realinode), file->f_flags,  in ovl_open_realfile()
74 static int ovl_change_flags(struct file *file, unsigned int flags)  in ovl_change_flags()  argument
76 	struct inode *inode = file_inode(file);  in ovl_change_flags()
81 	if (((flags ^ file->f_flags) & O_APPEND) && IS_APPEND(inode))  in ovl_change_flags()
85 		if (!file->f_mapping->a_ops ||  in ovl_change_flags()
86 		    !file->f_mapping->a_ops->direct_IO)  in ovl_change_flags()
90 	if (file->f_op->check_flags) {  in ovl_change_flags()
91 		err = file->f_op->check_flags(flags);  in ovl_change_flags()
96 	spin_lock(&file->f_lock);  in ovl_change_flags()
97 	file->f_flags = (file->f_flags & ~OVL_SETFL_MASK) | flags;  in ovl_change_flags()
98 	spin_unlock(&file->f_lock);  in ovl_change_flags()
103 static int ovl_real_fdget_meta(const struct file *file, struct fd *real,  in ovl_real_fdget_meta()  argument
106 	struct inode *inode = file_inode(file);  in ovl_real_fdget_meta()
110 	real->file = file->private_data;  in ovl_real_fdget_meta()
118 	if (unlikely(file_inode(real->file) != realinode)) {  in ovl_real_fdget_meta()
120 		real->file = ovl_open_realfile(file, realinode);  in ovl_real_fdget_meta()
122 		return PTR_ERR_OR_ZERO(real->file);  in ovl_real_fdget_meta()
126 	if (unlikely((file->f_flags ^ real->file->f_flags) & ~OVL_OPEN_FLAGS))  in ovl_real_fdget_meta()
127 		return ovl_change_flags(real->file, file->f_flags);  in ovl_real_fdget_meta()
132 static int ovl_real_fdget(const struct file *file, struct fd *real)  in ovl_real_fdget()  argument
134 	if (d_is_dir(file_dentry(file))) {  in ovl_real_fdget()
136 		real->file = ovl_dir_real_file(file, false);  in ovl_real_fdget()
138 		return PTR_ERR_OR_ZERO(real->file);  in ovl_real_fdget()
141 	return ovl_real_fdget_meta(file, real, false);  in ovl_real_fdget()
144 static int ovl_open(struct inode *inode, struct file *file)  in ovl_open()  argument
146 	struct file *realfile;  in ovl_open()
149 	err = ovl_maybe_copy_up(file_dentry(file), file->f_flags);  in ovl_open()
154 	file->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);  in ovl_open()
156 	realfile = ovl_open_realfile(file, ovl_inode_realdata(inode));  in ovl_open()
160 	file->private_data = realfile;  in ovl_open()
165 static int ovl_release(struct inode *inode, struct file *file)  in ovl_release()  argument
167 	fput(file->private_data);  in ovl_release()
172 static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)  in ovl_llseek()  argument
174 	struct inode *inode = file_inode(file);  in ovl_llseek()
185 			return file->f_pos;  in ovl_llseek()
188 			return vfs_setpos(file, 0, 0);  in ovl_llseek()
191 	ret = ovl_real_fdget(file, &real);  in ovl_llseek()
196 	 * Overlay file f_pos is the master copy that is preserved  in ovl_llseek()
200 	 * files, so we use the real file to perform seeks.  in ovl_llseek()
203 	real.file->f_pos = file->f_pos;  in ovl_llseek()
206 	ret = vfs_llseek(real.file, offset, whence);  in ovl_llseek()
209 	file->f_pos = real.file->f_pos;  in ovl_llseek()
217 static void ovl_file_accessed(struct file *file)  in ovl_file_accessed()  argument
221 	if (file->f_flags & O_NOATIME)  in ovl_file_accessed()
224 	inode = file_inode(file);  in ovl_file_accessed()
236 	touch_atime(&file->f_path);  in ovl_file_accessed()
287 	struct file *file = iocb->ki_filp;  in ovl_read_iter()  local
295 	ret = ovl_real_fdget(file, &real);  in ovl_read_iter()
301 	    (!real.file->f_mapping->a_ops ||  in ovl_read_iter()
302 	     !real.file->f_mapping->a_ops->direct_IO))  in ovl_read_iter()
305 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_read_iter()
307 		ret = vfs_iter_read(real.file, iter, &iocb->ki_pos,  in ovl_read_iter()
320 		kiocb_clone(&aio_req->iocb, iocb, real.file);  in ovl_read_iter()
322 		ret = vfs_iocb_iter_read(real.file, &aio_req->iocb, iter);  in ovl_read_iter()
328 	ovl_file_accessed(file);  in ovl_read_iter()
337 	struct file *file = iocb->ki_filp;  in ovl_write_iter()  local
338 	struct inode *inode = file_inode(file);  in ovl_write_iter()
350 	ret = file_remove_privs(file);  in ovl_write_iter()
354 	ret = ovl_real_fdget(file, &real);  in ovl_write_iter()
360 	    (!real.file->f_mapping->a_ops ||  in ovl_write_iter()
361 	     !real.file->f_mapping->a_ops->direct_IO))  in ovl_write_iter()
367 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_write_iter()
369 		file_start_write(real.file);  in ovl_write_iter()
370 		ret = vfs_iter_write(real.file, iter, &iocb->ki_pos,  in ovl_write_iter()
372 		file_end_write(real.file);  in ovl_write_iter()
383 		file_start_write(real.file);  in ovl_write_iter()
385 		__sb_writers_release(file_inode(real.file)->i_sb,  in ovl_write_iter()
390 		kiocb_clone(&aio_req->iocb, iocb, real.file);  in ovl_write_iter()
393 		ret = vfs_iocb_iter_write(real.file, &aio_req->iocb, iter);  in ovl_write_iter()
411  * and file_start_write(real.file) in ovl_write_iter().
414  * the real file.
416 static ssize_t ovl_splice_write(struct pipe_inode_info *pipe, struct file *out,  in ovl_splice_write()
437 	file_start_write(real.file);  in ovl_splice_write()
439 	ret = iter_file_splice_write(pipe, real.file, ppos, len, flags);  in ovl_splice_write()
441 	file_end_write(real.file);  in ovl_splice_write()
453 static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)  in ovl_fsync()  argument
459 	ret = ovl_sync_status(OVL_FS(file_inode(file)->i_sb));  in ovl_fsync()
463 	ret = ovl_real_fdget_meta(file, &real, !datasync);  in ovl_fsync()
467 	/* Don't sync lower file for fear of receiving EROFS error */  in ovl_fsync()
468 	if (file_inode(real.file) == ovl_inode_upper(file_inode(file))) {  in ovl_fsync()
469 		old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fsync()
470 		ret = vfs_fsync_range(real.file, start, end, datasync);  in ovl_fsync()
479 static int ovl_mmap(struct file *file, struct vm_area_struct *vma)  in ovl_mmap()  argument
481 	struct file *realfile = file->private_data;  in ovl_mmap()
488 	if (WARN_ON(file != vma->vm_file))  in ovl_mmap()
493 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_mmap()
496 	ovl_file_accessed(file);  in ovl_mmap()
501 static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len)  in ovl_fallocate()  argument
503 	struct inode *inode = file_inode(file);  in ovl_fallocate()
508 	ret = ovl_real_fdget(file, &real);  in ovl_fallocate()
512 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fallocate()
513 	ret = vfs_fallocate(real.file, mode, offset, len);  in ovl_fallocate()
524 static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice)  in ovl_fadvise()  argument
530 	ret = ovl_real_fdget(file, &real);  in ovl_fadvise()
534 	old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_fadvise()
535 	ret = vfs_fadvise(real.file, offset, len, advice);  in ovl_fadvise()
549 static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,  in ovl_copyfile()
550 			    struct file *file_out, loff_t pos_out,  in ovl_copyfile()
571 		ret = vfs_copy_file_range(real_in.file, pos_in,  in ovl_copyfile()
572 					  real_out.file, pos_out, len, flags);  in ovl_copyfile()
576 		ret = vfs_clone_file_range(real_in.file, pos_in,  in ovl_copyfile()
577 					   real_out.file, pos_out, len, flags);  in ovl_copyfile()
581 		ret = vfs_dedupe_file_range_one(real_in.file, pos_in,  in ovl_copyfile()
582 						real_out.file, pos_out, len,  in ovl_copyfile()
597 static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in,  in ovl_copy_file_range()
598 				   struct file *file_out, loff_t pos_out,  in ovl_copy_file_range()
605 static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in,  in ovl_remap_file_range()
606 				   struct file *file_out, loff_t pos_out,  in ovl_remap_file_range()
632 static int ovl_flush(struct file *file, fl_owner_t id)  in ovl_flush()  argument
638 	err = ovl_real_fdget(file, &real);  in ovl_flush()
642 	if (real.file->f_op->flush) {  in ovl_flush()
643 		old_cred = ovl_override_creds(file_inode(file)->i_sb);  in ovl_flush()
644 		err = real.file->f_op->flush(real.file, id);  in ovl_flush()