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Date:   Sun, 22 May 2022 14:51:57 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Christoph Hellwig <hch@lst.de>,
        Matthew Wilcox <willy@infradead.org>,
        linux-fsdevel@vger.kernel.org, Jens Axboe <axboe@kernel.dk>
Subject: Re: [RFC] what to do with IOCB_DSYNC?
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On Sun, May 22, 2022 at 12:41:36PM +0000, Al Viro wrote:
> Add
> #define IOMAP_DIO_NOSYNC (1 << 3)
> in iomap.h, pass IOMAP_DIO_PARTIAL | IOMAP_DIO_NOSYNC in btrfs and do
>                 if (iocb_is_dsync(iocb) && !(dio->flags & IOMAP_DIO_NOSYNC)) {
> in __iomap_dio_rw(), you mean?

Roughly, yes.

> I wonder if we want something of that sort in another user of IOMAP_DIO_PARTIAL
> (gfs2, that is)...

I don't think gfs2 needs it, but it might be worth to take another look
at how it handles sync writes.