---
name: "usb_buffer_unmap_sg"
section: "9"
platform: "linux"
package: "linux-manual-4.9"
version: "4.9.228-1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/usb_buffer_unmap_sg"
---

# usb\_buffer\_unmap\_sg(9)

free DMA mapping(s) for a scatterlist

## NAME

usb\_buffer\_unmap\_sg - free DMA mapping(s) for a scatterlist

## SYNOPSIS

**void usb\_buffer\_unmap\_sg(const struct usb\_device \*** *dev***, int** *is\_in***, struct scatterlist \*** *sg***, int** *n\_hw\_ents***);**

## ARGUMENTS

*dev*

device to which the scatterlist will be mapped

*is\_in*

mapping transfer direction

*sg*

the scatterlist to unmap

*n\_hw\_ents*

the positive return value from usb\_buffer\_map\_sg

## DESCRIPTION

Reverses the effect of **usb\_buffer\_map\_sg**.

## COPYRIGHT