The Write function detects that the disk has no space

When calling the Write function for asynchronous read and write, this time it is possible to return the ENOSPEC error code, when this error code occurs, memory pages already have a large amount of data, this time when the data is handled, the memory of the Pageout function will release these page table, After all, because of disk space, but can not guarantee that the page table in memory, always exist, waiting for the user to delete the disk space, and then re-write, after all, the data is not completely useless, to ensure the integrity and consistency of the data. There is a problem with how the current developer views the problem. Especially if the disk is offline and the memory runs out, causing the system to crash.

To view the source code from a certain angle, the write function knows how the disk is fully loaded and cannot be written. In particular, the underlying writepage function that deals with drives is how to obtain information about disk drive read and write.

The Write function detects that the disk has no space