C++ (Cpp) do_iter_readv_writevの例

コード例 #1

ファイル: read_write.c プロジェクト: Anjali05/linux

static ssize_t do_iter_read(struct file *file, struct iov_iter *iter,
		loff_t *pos, rwf_t flags)
{
	size_t tot_len;
	ssize_t ret = 0;

	if (!(file->f_mode & FMODE_READ))
		return -EBADF;
	if (!(file->f_mode & FMODE_CAN_READ))
		return -EINVAL;

	tot_len = iov_iter_count(iter);
	if (!tot_len)
		goto out;
	ret = rw_verify_area(READ, file, pos, tot_len);
	if (ret < 0)
		return ret;

	if (file->f_op->read_iter)
		ret = do_iter_readv_writev(file, iter, pos, READ, flags);
	else
		ret = do_loop_readv_writev(file, iter, pos, READ, flags);
out:
	if (ret >= 0)
		fsnotify_access(file);
	return ret;
}

コード例 #2

ファイル: read_write.c プロジェクト: Anjali05/linux

static ssize_t do_iter_write(struct file *file, struct iov_iter *iter,
		loff_t *pos, rwf_t flags)
{
	size_t tot_len;
	ssize_t ret = 0;

	if (!(file->f_mode & FMODE_WRITE))
		return -EBADF;
	if (!(file->f_mode & FMODE_CAN_WRITE))
		return -EINVAL;

	tot_len = iov_iter_count(iter);
	if (!tot_len)
		return 0;
	ret = rw_verify_area(WRITE, file, pos, tot_len);
	if (ret < 0)
		return ret;

	if (file->f_op->write_iter)
		ret = do_iter_readv_writev(file, iter, pos, WRITE, flags);
	else
		ret = do_loop_readv_writev(file, iter, pos, WRITE, flags);
	if (ret > 0)
		fsnotify_modify(file);
	return ret;
}

コード例 #3

ファイル: read_write.c プロジェクト: vishalbhoj/linux

static ssize_t do_readv_writev(int type, struct file *file,
			       const struct iovec __user * uvector,
			       unsigned long nr_segs, loff_t *pos)
{
	size_t tot_len;
	struct iovec iovstack[UIO_FASTIOV];
	struct iovec *iov = iovstack;
	struct iov_iter iter;
	ssize_t ret;
	io_fn_t fn;
	iov_fn_t fnv;
	iter_fn_t iter_fn;

	ret = import_iovec(type, uvector, nr_segs,
			   ARRAY_SIZE(iovstack), &iov, &iter);
	if (ret < 0)
		return ret;

	tot_len = iov_iter_count(&iter);
	if (!tot_len)
		goto out;
	ret = rw_verify_area(type, file, pos, tot_len);
	if (ret < 0)
		goto out;

	fnv = NULL;
	if (type == READ) {
		fn = file->f_op->read;
		fnv = file->f_op->aio_read;
		iter_fn = file->f_op->read_iter;
	} else {
		fn = (io_fn_t)file->f_op->write;
		fnv = file->f_op->aio_write;
		iter_fn = file->f_op->write_iter;
		file_start_write(file);
	}

	if (iter_fn)
		ret = do_iter_readv_writev(file, &iter, pos, iter_fn);
	else if (fnv)
		ret = do_sync_readv_writev(file, &iter, pos, fnv);
	else
		ret = do_loop_readv_writev(file, &iter, pos, fn);

	if (type != READ)
		file_end_write(file);

out:
	kfree(iov);
	if ((ret + (type == READ)) > 0) {
		if (type == READ)
			fsnotify_access(file);
		else
			fsnotify_modify(file);
	}
	return ret;
}

コード例 #4

ファイル: read_write.c プロジェクト: Abioy/kasan

static ssize_t compat_do_readv_writev(int type, struct file *file,
			       const struct compat_iovec __user *uvector,
			       unsigned long nr_segs, loff_t *pos)
{
	compat_ssize_t tot_len;
	struct iovec iovstack[UIO_FASTIOV];
	struct iovec *iov = iovstack;
	ssize_t ret;
	io_fn_t fn;
	iov_fn_t fnv;
	iter_fn_t iter_fn;

	ret = compat_rw_copy_check_uvector(type, uvector, nr_segs,
					       UIO_FASTIOV, iovstack, &iov);
	if (ret <= 0)
		goto out;

	tot_len = ret;
	ret = rw_verify_area(type, file, pos, tot_len);
	if (ret < 0)
		goto out;

	fnv = NULL;
	if (type == READ) {
		fn = file->f_op->read;
		fnv = file->f_op->aio_read;
		iter_fn = file->f_op->read_iter;
	} else {
		fn = (io_fn_t)file->f_op->write;
		fnv = file->f_op->aio_write;
		iter_fn = file->f_op->write_iter;
		file_start_write(file);
	}

	if (iter_fn)
		ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len,
						pos, iter_fn);
	else if (fnv)
		ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
						pos, fnv);
	else
		ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);

	if (type != READ)
		file_end_write(file);

out:
	if (iov != iovstack)
		kfree(iov);
	if ((ret + (type == READ)) > 0) {
		if (type == READ)
			fsnotify_access(file);
		else
			fsnotify_modify(file);
	}
	return ret;
}