Messages in this thread | ![/](/images/icornerl.gif) | | Date | Sun, 30 Aug 2009 18:39:17 +0200 | From | Christoph Hellwig <> | Subject | Re: [PATCH 07/17] vfs: Introduce new helpers for syncing after writing to O_SYNC file or IS_SYNC inode |
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On Sun, Aug 30, 2009 at 05:35:51PM +0100, Jamie Lokier wrote: > I like that. It looks really clear and self-documenting, if > vfs_fsync_range does what it sounds like, which is a nice change. > > If I've guessed right what that code does, proper O_RSYNC will be easy: > > int generic_sync_before_read(struct file *file, loff_t pos, loff_t count) > { > int is_sync = ((file->f_flags & O_SYNC) > || IS_SYNC(file->f_mapping->host)); > int is_dsync = is_sync || (file->f_flags & O_DSYNC); > > if (!is_dsync || !(file->f_flags & O_RSYNC)) > return 0; > return vfs_fsync_range(file, file->f_ath.denty, pos, > pos + count - 1, is_sync); > }
Yes. something like this.
> (By the way, did I mention Irix has range-fsync and range-fdatasync > system calls too :-) (actually fcntls))
Linux has sync_file_range which currently is a perfect way to lose your synced' data, but with two more flags and calls to ->fsync we could turn it into range-fsync/fdatasync. I'm not sure if that's a good idea or if we should just add a sys_fdatasync_rage systems call.
I don't quite see the point of a range-fsync, but it could be easily implemented as a flag.
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