xfs
[Top] [All Lists]

Re: [PATCH 04/14] xfs: reorder zeroing and flushing sequence in truncate

To: Christoph Hellwig <hch@xxxxxx>
Subject: Re: [PATCH 04/14] xfs: reorder zeroing and flushing sequence in truncate
From: Bob Peterson <rpeterso@xxxxxxxxxx>
Date: Thu, 5 May 2016 13:34:50 -0400 (EDT)
Cc: xfs@xxxxxxxxxxx, linux-fsdevel@xxxxxxxxxxxxxxx
Delivered-to: xfs@xxxxxxxxxxx
In-reply-to: <1462310947-16132-5-git-send-email-hch@xxxxxx>
References: <1462310947-16132-1-git-send-email-hch@xxxxxx> <1462310947-16132-5-git-send-email-hch@xxxxxx>
Thread-index: YnHmZI4AhjCsWsBqW9QvPTHhe9ih0w==
Thread-topic: reorder zeroing and flushing sequence in truncate
----- Original Message -----
> Currently zeroing out blocks and waiting for writeout is a bit of a mess in
> truncate.  This patch gives it a clear order in preparation for the iomap
> path:
> 
>  (1) we first wait for any direct I/O to complete to prevent any races
>      for it
>  (2) we then perform the actual zeroing, and only use the truncate_page
>      helpers for truncating down.  The truncate up case already is
>      handled by the separate call to xfs_zero_eof.
>  (3) only then we write back dirty data, as zeroing block may cause
>      dirty pages when using either xfs_zero_eof or the new iomap
>      infrastructure.
> 
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> +      * Start with zeroing any data beyond EOF that we may expose on file
> +      & extension, or zeroing out the rest of the block on a downward

This "&" should be "*".

Reviewed-by: Bob Peterson <rpeterso@xxxxxxxxxx>

<Prev in Thread] Current Thread [Next in Thread>