From: Dan Williams <dan.j.williams@intel.com>
To: Christoph Hellwig <hch@lst.de>
Cc: "Darrick J. Wong" <djwong@kernel.org>,
Eric Sandeen <sandeen@sandeen.net>,
Mike Snitzer <snitzer@redhat.com>,
Ira Weiny <ira.weiny@intel.com>,
device-mapper development <dm-devel@redhat.com>,
linux-xfs <linux-xfs@vger.kernel.org>,
Linux NVDIMM <nvdimm@lists.linux.dev>,
linux-s390 <linux-s390@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-erofs@lists.ozlabs.org,
linux-ext4 <linux-ext4@vger.kernel.org>,
virtualization@lists.linux-foundation.org
Subject: Re: futher decouple DAX from block devices
Date: Thu, 4 Nov 2021 11:10:19 -0700 [thread overview]
Message-ID: <CAPcyv4jbjc+XtX5RX5OL3vPadsYZwoK1NG1qC5AcpySBu5tL4g@mail.gmail.com> (raw)
In-Reply-To: <20211104173559.GB31740@lst.de>
On Thu, Nov 4, 2021 at 10:36 AM Christoph Hellwig <hch@lst.de> wrote:
>
> On Thu, Nov 04, 2021 at 10:34:17AM -0700, Darrick J. Wong wrote:
> > /me wonders, are block devices going away? Will mkfs.xfs have to learn
> > how to talk to certain chardevs? I guess jffs2 and others already do
> > that kind of thing... but I suppose I can wait for the real draft to
> > show up to ramble further. ;)
>
> Right now I've mostly been looking into the kernel side. An no, I
> do not expect /dev/pmem* to go away as you'll still need it for a
> not DAX aware file system and/or application (such as mkfs initially).
>
> But yes, just pointing mkfs to the chardev should be doable with very
> little work. We can point it to a regular file after all.
Note that I've avoided implementing read/write fops for dax devices
partly out of concern for not wanting to figure out shared-mmap vs
write coherence issues, but also because of a bet with Dave Hansen
that device-dax not grow features like what happened to hugetlbfs. So
it would seem mkfs would need to switch to mmap I/O, or bite the
bullet and implement read/write fops in the driver.
WARNING: multiple messages have this Message-ID (diff)
From: Dan Williams <dan.j.williams@intel.com>
To: Christoph Hellwig <hch@lst.de>
Cc: Linux NVDIMM <nvdimm@lists.linux.dev>,
linux-erofs@lists.ozlabs.org, Mike Snitzer <snitzer@redhat.com>,
linux-s390 <linux-s390@vger.kernel.org>,
"Darrick J. Wong" <djwong@kernel.org>,
Eric Sandeen <sandeen@sandeen.net>,
virtualization@lists.linux-foundation.org,
linux-xfs <linux-xfs@vger.kernel.org>,
device-mapper development <dm-devel@redhat.com>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-ext4 <linux-ext4@vger.kernel.org>,
Ira Weiny <ira.weiny@intel.com>
Subject: Re: [dm-devel] futher decouple DAX from block devices
Date: Thu, 4 Nov 2021 11:10:19 -0700 [thread overview]
Message-ID: <CAPcyv4jbjc+XtX5RX5OL3vPadsYZwoK1NG1qC5AcpySBu5tL4g@mail.gmail.com> (raw)
In-Reply-To: <20211104173559.GB31740@lst.de>
On Thu, Nov 4, 2021 at 10:36 AM Christoph Hellwig <hch@lst.de> wrote:
>
> On Thu, Nov 04, 2021 at 10:34:17AM -0700, Darrick J. Wong wrote:
> > /me wonders, are block devices going away? Will mkfs.xfs have to learn
> > how to talk to certain chardevs? I guess jffs2 and others already do
> > that kind of thing... but I suppose I can wait for the real draft to
> > show up to ramble further. ;)
>
> Right now I've mostly been looking into the kernel side. An no, I
> do not expect /dev/pmem* to go away as you'll still need it for a
> not DAX aware file system and/or application (such as mkfs initially).
>
> But yes, just pointing mkfs to the chardev should be doable with very
> little work. We can point it to a regular file after all.
Note that I've avoided implementing read/write fops for dax devices
partly out of concern for not wanting to figure out shared-mmap vs
write coherence issues, but also because of a bet with Dave Hansen
that device-dax not grow features like what happened to hugetlbfs. So
it would seem mkfs would need to switch to mmap I/O, or bite the
bullet and implement read/write fops in the driver.
--
dm-devel mailing list
dm-devel@redhat.com
https://listman.redhat.com/mailman/listinfo/dm-devel
WARNING: multiple messages have this Message-ID (diff)
From: Dan Williams <dan.j.williams@intel.com>
To: Christoph Hellwig <hch@lst.de>
Cc: Linux NVDIMM <nvdimm@lists.linux.dev>,
linux-erofs@lists.ozlabs.org, Mike Snitzer <snitzer@redhat.com>,
linux-s390 <linux-s390@vger.kernel.org>,
"Darrick J. Wong" <djwong@kernel.org>,
Eric Sandeen <sandeen@sandeen.net>,
virtualization@lists.linux-foundation.org,
linux-xfs <linux-xfs@vger.kernel.org>,
device-mapper development <dm-devel@redhat.com>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-ext4 <linux-ext4@vger.kernel.org>,
Ira Weiny <ira.weiny@intel.com>
Subject: Re: futher decouple DAX from block devices
Date: Thu, 4 Nov 2021 11:10:19 -0700 [thread overview]
Message-ID: <CAPcyv4jbjc+XtX5RX5OL3vPadsYZwoK1NG1qC5AcpySBu5tL4g@mail.gmail.com> (raw)
In-Reply-To: <20211104173559.GB31740@lst.de>
On Thu, Nov 4, 2021 at 10:36 AM Christoph Hellwig <hch@lst.de> wrote:
>
> On Thu, Nov 04, 2021 at 10:34:17AM -0700, Darrick J. Wong wrote:
> > /me wonders, are block devices going away? Will mkfs.xfs have to learn
> > how to talk to certain chardevs? I guess jffs2 and others already do
> > that kind of thing... but I suppose I can wait for the real draft to
> > show up to ramble further. ;)
>
> Right now I've mostly been looking into the kernel side. An no, I
> do not expect /dev/pmem* to go away as you'll still need it for a
> not DAX aware file system and/or application (such as mkfs initially).
>
> But yes, just pointing mkfs to the chardev should be doable with very
> little work. We can point it to a regular file after all.
Note that I've avoided implementing read/write fops for dax devices
partly out of concern for not wanting to figure out shared-mmap vs
write coherence issues, but also because of a bet with Dave Hansen
that device-dax not grow features like what happened to hugetlbfs. So
it would seem mkfs would need to switch to mmap I/O, or bite the
bullet and implement read/write fops in the driver.
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
WARNING: multiple messages have this Message-ID (diff)
From: Dan Williams <dan.j.williams@intel.com>
To: Christoph Hellwig <hch@lst.de>
Cc: Linux NVDIMM <nvdimm@lists.linux.dev>,
linux-erofs@lists.ozlabs.org, Mike Snitzer <snitzer@redhat.com>,
linux-s390 <linux-s390@vger.kernel.org>,
"Darrick J. Wong" <djwong@kernel.org>,
Eric Sandeen <sandeen@sandeen.net>,
virtualization@lists.linux-foundation.org,
linux-xfs <linux-xfs@vger.kernel.org>,
device-mapper development <dm-devel@redhat.com>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-ext4 <linux-ext4@vger.kernel.org>,
Ira Weiny <ira.weiny@intel.com>
Subject: Re: futher decouple DAX from block devices
Date: Thu, 4 Nov 2021 11:10:19 -0700 [thread overview]
Message-ID: <CAPcyv4jbjc+XtX5RX5OL3vPadsYZwoK1NG1qC5AcpySBu5tL4g@mail.gmail.com> (raw)
In-Reply-To: <20211104173559.GB31740@lst.de>
On Thu, Nov 4, 2021 at 10:36 AM Christoph Hellwig <hch@lst.de> wrote:
>
> On Thu, Nov 04, 2021 at 10:34:17AM -0700, Darrick J. Wong wrote:
> > /me wonders, are block devices going away? Will mkfs.xfs have to learn
> > how to talk to certain chardevs? I guess jffs2 and others already do
> > that kind of thing... but I suppose I can wait for the real draft to
> > show up to ramble further. ;)
>
> Right now I've mostly been looking into the kernel side. An no, I
> do not expect /dev/pmem* to go away as you'll still need it for a
> not DAX aware file system and/or application (such as mkfs initially).
>
> But yes, just pointing mkfs to the chardev should be doable with very
> little work. We can point it to a regular file after all.
Note that I've avoided implementing read/write fops for dax devices
partly out of concern for not wanting to figure out shared-mmap vs
write coherence issues, but also because of a bet with Dave Hansen
that device-dax not grow features like what happened to hugetlbfs. So
it would seem mkfs would need to switch to mmap I/O, or bite the
bullet and implement read/write fops in the driver.
next prev parent reply other threads:[~2021-11-04 18:10 UTC|newest]
Thread overview: 197+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-18 4:40 futher decouple DAX from block devices Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` [PATCH 01/11] dm: make the DAX support dependend on CONFIG_FS_DAX Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-27 20:53 ` Dan Williams
2021-10-27 20:53 ` [dm-devel] " Dan Williams
2021-10-27 20:53 ` Dan Williams
2021-10-27 20:53 ` Dan Williams
2021-11-01 16:12 ` Mike Snitzer
2021-11-01 16:12 ` Mike Snitzer
2021-11-01 16:12 ` [dm-devel] " Mike Snitzer
2021-11-01 16:12 ` Mike Snitzer
2021-10-18 4:40 ` [PATCH 02/11] dax: remove CONFIG_DAX_DRIVER Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-27 20:54 ` Dan Williams
2021-10-27 20:54 ` [dm-devel] " Dan Williams
2021-10-27 20:54 ` Dan Williams
2021-10-27 20:54 ` Dan Williams
2021-10-18 4:40 ` [PATCH 03/11] dax: simplify the dax_device <-> gendisk association Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-27 22:03 ` Dan Williams
2021-10-27 22:03 ` [dm-devel] " Dan Williams
2021-10-27 22:03 ` Dan Williams
2021-10-27 22:03 ` Dan Williams
2021-10-29 4:57 ` Ira Weiny
2021-10-29 4:57 ` [dm-devel] " Ira Weiny
2021-10-29 4:57 ` Ira Weiny
2021-10-29 4:57 ` Ira Weiny
2021-11-01 16:28 ` Mike Snitzer
2021-11-01 16:28 ` [dm-devel] " Mike Snitzer
2021-11-01 16:28 ` Mike Snitzer
2021-11-01 16:28 ` Mike Snitzer
2021-10-18 4:40 ` [PATCH 04/11] dax: remove the pgmap sanity checks in generic_fsdax_supported Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-27 23:02 ` Dan Williams
2021-10-27 23:02 ` Dan Williams
2021-10-27 23:02 ` [dm-devel] " Dan Williams
2021-10-27 23:02 ` Dan Williams
2021-10-18 4:40 ` [PATCH 05/11] dax: move the partition alignment check into fs_dax_get_by_bdev Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-27 23:07 ` Dan Williams
2021-10-27 23:07 ` Dan Williams
2021-10-27 23:07 ` [dm-devel] " Dan Williams
2021-10-27 23:07 ` Dan Williams
2021-10-18 4:40 ` [PATCH 06/11] xfs: factor out a xfs_setup_dax helper Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 16:43 ` Darrick J. Wong
2021-10-18 16:43 ` [dm-devel] " Darrick J. Wong
2021-10-18 16:43 ` Darrick J. Wong
2021-10-19 7:23 ` Christoph Hellwig
2021-10-19 7:23 ` Christoph Hellwig
2021-10-19 7:23 ` [dm-devel] " Christoph Hellwig
2021-10-19 7:23 ` Christoph Hellwig
2021-10-27 23:37 ` Dan Williams
2021-10-27 23:37 ` [dm-devel] " Dan Williams
2021-10-27 23:37 ` Dan Williams
2021-10-27 23:37 ` Dan Williams
2021-10-18 4:40 ` [PATCH 07/11] dax: remove dax_capable Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 12:25 ` Gao Xiang
2021-10-18 12:25 ` [dm-devel] " Gao Xiang
2021-10-18 12:25 ` Gao Xiang
2021-10-19 15:44 ` [dm-devel] " Darrick J. Wong
2021-10-19 15:44 ` Darrick J. Wong
2021-10-19 15:44 ` Darrick J. Wong
2021-10-28 0:20 ` Dan Williams
2021-10-28 0:20 ` Dan Williams
2021-10-28 0:20 ` Dan Williams
2021-10-28 0:20 ` Dan Williams
2021-10-28 0:16 ` Dan Williams
2021-10-28 0:16 ` [dm-devel] " Dan Williams
2021-10-28 0:16 ` Dan Williams
2021-10-28 0:16 ` Dan Williams
2021-11-01 16:17 ` Mike Snitzer
2021-11-01 16:17 ` [dm-devel] " Mike Snitzer
2021-11-01 16:17 ` Mike Snitzer
2021-11-01 16:17 ` Mike Snitzer
2021-10-18 4:40 ` [PATCH 08/11] dm-linear: add a linear_dax_pgoff helper Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-28 1:32 ` Dan Williams
2021-10-28 1:32 ` [dm-devel] " Dan Williams
2021-10-28 1:32 ` Dan Williams
2021-10-28 1:32 ` Dan Williams
2021-11-01 16:18 ` Mike Snitzer
2021-11-01 16:18 ` [dm-devel] " Mike Snitzer
2021-11-01 16:18 ` Mike Snitzer
2021-11-01 16:18 ` Mike Snitzer
2021-10-18 4:40 ` [PATCH 09/11] dm-log-writes: add a log_writes_dax_pgoff helper Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-28 1:36 ` Dan Williams
2021-10-28 1:36 ` [dm-devel] " Dan Williams
2021-10-28 1:36 ` Dan Williams
2021-10-28 1:36 ` Dan Williams
2021-11-01 16:19 ` Mike Snitzer
2021-11-01 16:19 ` [dm-devel] " Mike Snitzer
2021-11-01 16:19 ` Mike Snitzer
2021-11-01 16:19 ` Mike Snitzer
2021-10-18 4:40 ` [PATCH 10/11] dm-stripe: add a stripe_dax_pgoff helper Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-28 1:41 ` Dan Williams
2021-10-28 1:41 ` [dm-devel] " Dan Williams
2021-10-28 1:41 ` Dan Williams
2021-10-28 1:41 ` Dan Williams
2021-11-01 16:21 ` Mike Snitzer
2021-11-01 16:21 ` [dm-devel] " Mike Snitzer
2021-11-01 16:21 ` Mike Snitzer
2021-11-01 16:21 ` Mike Snitzer
2021-10-18 4:40 ` [PATCH 11/11] dax: move bdev_dax_pgoff to fs/dax.c Christoph Hellwig
2021-10-18 4:40 ` [dm-devel] " Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-18 4:40 ` Christoph Hellwig
2021-10-28 1:44 ` Dan Williams
2021-10-28 1:44 ` [dm-devel] " Dan Williams
2021-10-28 1:44 ` Dan Williams
2021-10-28 1:44 ` Dan Williams
2021-10-27 20:46 ` futher decouple DAX from block devices Dan Williams
2021-10-27 20:46 ` [dm-devel] " Dan Williams
2021-10-27 20:46 ` Dan Williams
2021-10-27 20:46 ` Dan Williams
2021-10-28 23:51 ` Stephen Rothwell
2021-10-28 23:51 ` [dm-devel] " Stephen Rothwell
2021-10-28 23:51 ` Stephen Rothwell
2021-10-28 23:51 ` Stephen Rothwell
2021-10-29 15:42 ` Dan Williams
2021-10-29 15:42 ` [dm-devel] " Dan Williams
2021-10-29 15:42 ` Dan Williams
2021-10-29 15:42 ` Dan Williams
2021-10-29 15:55 ` Darrick J. Wong
2021-10-29 15:55 ` [dm-devel] " Darrick J. Wong
2021-10-29 15:55 ` Darrick J. Wong
2021-10-29 16:16 ` Dan Williams
2021-10-29 16:16 ` Dan Williams
2021-10-29 16:16 ` [dm-devel] " Dan Williams
2021-10-29 16:16 ` Dan Williams
2021-11-03 17:59 ` Eric Sandeen
2021-11-03 17:59 ` [dm-devel] " Eric Sandeen
2021-11-03 17:59 ` Eric Sandeen
2021-11-04 8:17 ` Christoph Hellwig
2021-11-04 8:17 ` [dm-devel] " Christoph Hellwig
2021-11-04 8:17 ` Christoph Hellwig
2021-11-04 8:17 ` Christoph Hellwig
2021-11-04 17:34 ` Darrick J. Wong
2021-11-04 17:34 ` [dm-devel] " Darrick J. Wong
2021-11-04 17:34 ` Darrick J. Wong
2021-11-04 17:35 ` Christoph Hellwig
2021-11-04 17:35 ` [dm-devel] " Christoph Hellwig
2021-11-04 17:35 ` Christoph Hellwig
2021-11-04 17:35 ` Christoph Hellwig
2021-11-04 18:10 ` Dan Williams [this message]
2021-11-04 18:10 ` Dan Williams
2021-11-04 18:10 ` Dan Williams
2021-11-04 18:10 ` [dm-devel] " Dan Williams
2021-11-04 19:04 ` Darrick J. Wong
2021-11-04 19:04 ` [dm-devel] " Darrick J. Wong
2021-11-04 19:04 ` Darrick J. Wong
2021-11-05 3:09 ` Theodore Ts'o
2021-11-05 3:09 ` Theodore Ts'o
2021-11-05 3:09 ` [dm-devel] " Theodore Ts'o
2021-11-05 3:09 ` Theodore Ts'o
2021-11-05 3:30 ` Matthew Wilcox
2021-11-05 3:30 ` Matthew Wilcox
2021-11-05 3:30 ` Matthew Wilcox
2021-11-05 3:30 ` [dm-devel] " Matthew Wilcox
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