From: Christoph Hellwig <hch@lst.de>
To: Minwoo Im <minwoo.im.dev@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>, Keith Busch <kbusch@kernel.org>,
Sagi Grimberg <sagi@grimberg.me>,
Kanchan Joshi <joshiiitr@gmail.com>,
Javier Gonz??lez <javier.gonz@samsung.com>,
linux-nvme@lists.infradead.org
Subject: Re: [PATCH 13/13] nvme: introduce generic per-namespace chardev
Date: Mon, 12 Apr 2021 09:44:55 +0200 [thread overview]
Message-ID: <20210412074455.GA3653@lst.de> (raw)
In-Reply-To: <20210409112401.GF2085@localhost>
On Fri, Apr 09, 2021 at 08:24:01PM +0900, Minwoo Im wrote:
> I think if we don't have a route to the live controller from the
> multipath node /dev/ng0n1, how does application figure out controller
> node to request admin commands like Identify Namespace before their
> own I/O ?
>
> We have sysfs, but it does not provide every information about the
> namespace. Or is there any charming way to find out the live
> controller from a head node through sysfs or something that I missed
> here ? :)
The devie links points to the subsystem, which then points to the
controllers:
root@testvm:/sys/class/nvme-generic/ng0n1# ls -l device/
total 0
-r--r--r-- 1 root root 4096 Apr 12 07:43 firmware_rev
-rw-r--r-- 1 root root 4096 Apr 12 07:44 iopolicy
-r--r--r-- 1 root root 4096 Apr 12 07:43 model
drwxr-xr-x 3 root root 0 Apr 12 07:43 ng0n1
drwxr-xr-x 3 root root 0 Apr 12 07:43 ng0n2
lrwxrwxrwx 1 root root 0 Apr 12 07:44 nvme0 -> ../../nvme-fabrics/ctl/nvme0
drwxr-xr-x 9 root root 0 Apr 12 07:43 nvme0n1
drwxr-xr-x 9 root root 0 Apr 12 07:43 nvme0n2
lrwxrwxrwx 1 root root 0 Apr 12 07:44 nvme1 -> ../../nvme-fabrics/ctl/nvme1
drwxr-xr-x 2 root root 0 Apr 12 07:44 power
-r--r--r-- 1 root root 4096 Apr 12 07:43 serial
-r--r--r-- 1 root root 4096 Apr 12 07:44 subsysnqn
lrwxrwxrwx 1 root root 0 Apr 12 07:43 subsystem -> ../../../../class/nvme-subsystem
-rw-r--r-- 1 root root 4096 Apr 12 07:43 uevent
_______________________________________________
Linux-nvme mailing list
Linux-nvme@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-nvme
next prev parent reply other threads:[~2021-04-12 7:45 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20210408121108eucas1p1fb60de8498a7461b453295497c206246@eucas1p1.samsung.com>
2021-04-08 12:08 ` nvme ioctl refactor and generic per-namespace char device Christoph Hellwig
2021-04-08 12:08 ` [PATCH 01/13] nvme: add a nvme_ns_head_multipath helper Christoph Hellwig
2021-04-09 2:33 ` Chaitanya Kulkarni
2021-04-08 12:08 ` [PATCH 02/13] nvme: cleanup setting the disk name Christoph Hellwig
2021-04-08 12:08 ` [PATCH 03/13] nvme: pass a user pointer to nvme_nvm_ioctl Christoph Hellwig
2021-04-08 12:08 ` [PATCH 04/13] nvme: factor out a nvme_ns_ioctl helper Christoph Hellwig
2021-04-09 2:40 ` Chaitanya Kulkarni
2021-04-08 12:08 ` [PATCH 05/13] nvme: simplify the compat ioctl handling Christoph Hellwig
2021-04-09 2:42 ` Chaitanya Kulkarni
2021-04-09 5:39 ` Christoph Hellwig
2021-04-08 12:08 ` [PATCH 06/13] nvme: simplify block device ioctl handling for the !multipath case Christoph Hellwig
2021-04-08 12:08 ` [PATCH 07/13] nvme: don't bother to look up a namespace for controller ioctls Christoph Hellwig
2021-04-08 12:08 ` [PATCH 08/13] nvme: move the ioctl code to a separate file Christoph Hellwig
2021-04-09 2:45 ` Chaitanya Kulkarni
2021-04-08 12:08 ` [PATCH 09/13] nvme: factor out a nvme_tryget_ns_head helper Christoph Hellwig
2021-04-09 2:46 ` Chaitanya Kulkarni
2021-04-09 5:39 ` Christoph Hellwig
2021-04-09 5:40 ` Chaitanya Kulkarni
2021-04-09 9:18 ` Kanchan Joshi
2021-04-09 9:49 ` Christoph Hellwig
2021-04-08 12:08 ` [PATCH 10/13] nvme: move nvme_ns_head_ops to multipath.c Christoph Hellwig
2021-04-09 2:47 ` Chaitanya Kulkarni
2021-04-08 12:08 ` [PATCH 11/13] nvme: factor out nvme_ns_open and nvme_ns_release helpers Christoph Hellwig
2021-04-09 2:48 ` Chaitanya Kulkarni
2021-04-08 12:08 ` [PATCH 12/13] nvme: let namespace probing continue for unsupported features Christoph Hellwig
2021-04-08 22:42 ` Keith Busch
2021-04-09 5:39 ` Christoph Hellwig
2021-04-09 5:47 ` Keith Busch
2021-04-09 5:53 ` Christoph Hellwig
2021-04-08 12:08 ` [PATCH 13/13] nvme: introduce generic per-namespace chardev Christoph Hellwig
2021-04-08 16:56 ` Keith Busch
2021-04-08 17:00 ` Christoph Hellwig
2021-04-09 6:14 ` Christoph Hellwig
2021-04-09 14:29 ` Keith Busch
2021-04-09 14:35 ` Christoph Hellwig
2021-04-09 7:29 ` Minwoo Im
2021-04-09 7:54 ` Christoph Hellwig
2021-04-09 8:02 ` Minwoo Im
2021-04-09 9:52 ` Christoph Hellwig
2021-04-09 11:24 ` Minwoo Im
2021-04-12 7:44 ` Christoph Hellwig [this message]
2021-04-12 11:52 ` Javier Gonz??lez
2021-04-08 22:43 ` nvme ioctl refactor and generic per-namespace char device Keith Busch
2021-04-09 17:45 ` Javier Gonz??lez
2021-04-10 6:46 ` Christoph Hellwig
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210412074455.GA3653@lst.de \
--to=hch@lst.de \
--cc=javier.gonz@samsung.com \
--cc=joshiiitr@gmail.com \
--cc=kbusch@kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=minwoo.im.dev@gmail.com \
--cc=sagi@grimberg.me \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).