5c53b417cd
Previously, reading from or writing to a character device would not update the file position on the corresponding filp object. Performing this update correctly is not trivial: during and after the I/O operation, the filp object must not be locked. Ideally, read/write requests on a filp that is already involved in a read/write operation, should be queued. For now, we optimistically update the file position at the start of the I/O; this works under the assumptions listed in the corresponding comment. Change-Id: I172a61781850423709924390ae3df1f2d1f94707