示例#1
0
/*
 * Atomic create+open operation
 *
 * If the filesystem doesn't support this, then fall back to separate
 * 'mknod' + 'open' requests.
 */
static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode,
			    struct nameidata *nd)
{
	int err;
	struct inode *inode;
	struct fuse_conn *fc = get_fuse_conn(dir);
	struct fuse_req *req;
	struct fuse_req *forget_req;
	struct fuse_open_in inarg;
	struct fuse_open_out outopen;
	struct fuse_entry_out outentry;
	struct fuse_file *ff;
	struct file *file;
	int flags = nd->intent.open.flags - 1;

	if (fc->no_create)
		return -ENOSYS;

	if (flags & O_DIRECT)
		return -EINVAL;

	forget_req = fuse_get_req(fc);
	if (IS_ERR(forget_req))
		return PTR_ERR(forget_req);

	req = fuse_get_req(fc);
	err = PTR_ERR(req);
	if (IS_ERR(req))
		goto out_put_forget_req;

	err = -ENOMEM;
	ff = fuse_file_alloc();
	if (!ff)
		goto out_put_request;

	flags &= ~O_NOCTTY;
	memset(&inarg, 0, sizeof(inarg));
	memset(&outentry, 0, sizeof(outentry));
	inarg.flags = flags;
	inarg.mode = mode;
	req->in.h.opcode = FUSE_CREATE;
	req->in.h.nodeid = get_node_id(dir);
	req->in.numargs = 2;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = entry->d_name.len + 1;
	req->in.args[1].value = entry->d_name.name;
	req->out.numargs = 2;
	if (fc->minor < 9)
		req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
	else
		req->out.args[0].size = sizeof(outentry);
	req->out.args[0].value = &outentry;
	req->out.args[1].size = sizeof(outopen);
	req->out.args[1].value = &outopen;
	request_send(fc, req);
	err = req->out.h.error;
	if (err) {
		if (err == -ENOSYS)
			fc->no_create = 1;
		goto out_free_ff;
	}

	err = -EIO;
	if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid))
		goto out_free_ff;

	fuse_put_request(fc, req);
	inode = fuse_iget(dir->i_sb, outentry.nodeid, outentry.generation,
			  &outentry.attr, entry_attr_timeout(&outentry), 0);
	if (!inode) {
		flags &= ~(O_CREAT | O_EXCL | O_TRUNC);
		ff->fh = outopen.fh;
		fuse_sync_release(fc, ff, outentry.nodeid, flags);
		fuse_send_forget(fc, forget_req, outentry.nodeid, 1);
		return -ENOMEM;
	}
	fuse_put_request(fc, forget_req);
	d_instantiate(entry, inode);
	fuse_change_entry_timeout(entry, &outentry);
	fuse_invalidate_attr(dir);
	file = lookup_instantiate_filp(nd, entry, generic_file_open);
	if (IS_ERR(file)) {
		ff->fh = outopen.fh;
		fuse_sync_release(fc, ff, outentry.nodeid, flags);
		return PTR_ERR(file);
	}
	fuse_finish_open(inode, file, ff, &outopen);
	return 0;

 out_free_ff:
	fuse_file_free(ff);
 out_put_request:
	fuse_put_request(fc, req);
 out_put_forget_req:
	fuse_put_request(fc, forget_req);
	return err;
}
示例#2
0
文件: dir.c 项目: Flipkart/linux
/*
 * Atomic create+open operation
 *
 * If the filesystem doesn't support this, then fall back to separate
 * 'mknod' + 'open' requests.
 */
static int fuse_create_open(struct inode *dir, struct dentry *entry,
			    struct file *file, unsigned flags,
			    umode_t mode, int *opened)
{
	int err;
	struct inode *inode;
	struct fuse_conn *fc = get_fuse_conn(dir);
	FUSE_ARGS(args);
	struct fuse_forget_link *forget;
	struct fuse_create_in inarg;
	struct fuse_open_out outopen;
	struct fuse_entry_out outentry;
	struct fuse_file *ff;

	/* Userspace expects S_IFREG in create mode */
	BUG_ON((mode & S_IFMT) != S_IFREG);

	forget = fuse_alloc_forget();
	err = -ENOMEM;
	if (!forget)
		goto out_err;

	err = -ENOMEM;
	ff = fuse_file_alloc(fc);
	if (!ff)
		goto out_put_forget_req;

	if (!fc->dont_mask)
		mode &= ~current_umask();

	flags &= ~O_NOCTTY;
	memset(&inarg, 0, sizeof(inarg));
	memset(&outentry, 0, sizeof(outentry));
	inarg.flags = flags;
	inarg.mode = mode;
	inarg.umask = current_umask();
	args.in.h.opcode = FUSE_CREATE;
	args.in.h.nodeid = get_node_id(dir);
	args.in.numargs = 2;
	args.in.args[0].size = sizeof(inarg);
	args.in.args[0].value = &inarg;
	args.in.args[1].size = entry->d_name.len + 1;
	args.in.args[1].value = entry->d_name.name;
	args.out.numargs = 2;
	args.out.args[0].size = sizeof(outentry);
	args.out.args[0].value = &outentry;
	args.out.args[1].size = sizeof(outopen);
	args.out.args[1].value = &outopen;
	err = fuse_simple_request(fc, &args);
	if (err)
		goto out_free_ff;

	err = -EIO;
	if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid))
		goto out_free_ff;

	ff->fh = outopen.fh;
	ff->nodeid = outentry.nodeid;
	ff->open_flags = outopen.open_flags;
	inode = fuse_iget(dir->i_sb, outentry.nodeid, outentry.generation,
			  &outentry.attr, entry_attr_timeout(&outentry), 0);
	if (!inode) {
		flags &= ~(O_CREAT | O_EXCL | O_TRUNC);
		fuse_sync_release(ff, flags);
		fuse_queue_forget(fc, forget, outentry.nodeid, 1);
		err = -ENOMEM;
		goto out_err;
	}
	kfree(forget);
	d_instantiate(entry, inode);
	fuse_change_entry_timeout(entry, &outentry);
	fuse_invalidate_attr(dir);
	err = finish_open(file, entry, generic_file_open, opened);
	if (err) {
		fuse_sync_release(ff, flags);
	} else {
		file->private_data = fuse_file_get(ff);
		fuse_finish_open(inode, file);
	}
	return err;

out_free_ff:
	fuse_file_free(ff);
out_put_forget_req:
	kfree(forget);
out_err:
	return err;
}