Re: [PATCH] Wait for all I/O on truncate to zero file size

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

On Tue, Sep 23, 2008 at 03:05:12PM +1000, Lachlan McIlroy wrote:
> It's possible to have outstanding xfs_ioend_t's queued when the file
> size is zero.  This can happen in the direct I/O path when a direct
> I/O write fails due to ENOSPC.  In this case the xfs_ioend_t will still
> be queued (ie xfs_end_io_direct() does not know that the I/O failed so
> can't force the xfs_ioend_t to be flushed synchronously).
>
> When we truncate a file on unlink we don't know to wait for these
> xfs_ioend_ts and we can have a use-after-free situation if the inode
> is reclaimed before the xfs_ioend_t is finally processed.
>
> As was suggested by Dave Chinner lets wait for all I/Os to complete
> when truncating the file size to zero.

Looks good.