From: Al Viro <viro@zeniv.linux.org.uk>
To: Christoph Hellwig <hch@lst.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Rafael J. Wysocki" <rafael@kernel.org>,
linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org
Subject: Re: [PATCH 06/24] md: open code vfs_stat in md_setup_drive
Date: Tue, 21 Jul 2020 17:55:39 +0100 [thread overview]
Message-ID: <20200721165539.GT2786714@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20200721162818.197315-7-hch@lst.de>
On Tue, Jul 21, 2020 at 06:28:00PM +0200, Christoph Hellwig wrote:
> Instead of passing a kernel pointer to vfs_stat by relying on the
> implicit set_fs(KERNEL_DS) in md_setup_drive, just open code the
> trivial getattr, and use the opportunity to move a little bit more
> code from the caller into the new helper.
Ugh...
> +static void __init md_lookup_dev(const char *devname, dev_t *dev)
> +{
> + struct kstat stat;
> + struct path path;
> + char filename[64];
> +
> + if (strncmp(devname, "/dev/", 5) == 0)
> + devname += 5;
> + snprintf(filename, 63, "/dev/%s", devname);
> +
> + if (!kern_path(filename, LOOKUP_FOLLOW, &path) &&
> + !vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_NO_AUTOMOUNT) &&
> + S_ISBLK(stat.mode))
> + *dev = new_decode_dev(stat.rdev);
> + path_put(&path);
> +}
How about fs/for_init.c and putting the damn helpers there? With
calling conventions as close to syscalls as possible, and a fat
comment regarding their intended use being _ONLY_ the setup
in should-have-been-done-in-userland parts of init?
I really want to keep the surface as small as possible - we had
fun shite several releases ago when somebody tried that kind of
crap (with open(), IIRC). Let's not go there again...
next prev parent reply other threads:[~2020-07-21 16:56 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-21 16:27 add file system helpers that take kernel pointers for the init code v2 Christoph Hellwig
2020-07-21 16:27 ` [PATCH 01/24] fs: refactor do_mount Christoph Hellwig
2020-07-21 16:27 ` [PATCH 02/24] fs: refactor ksys_umount Christoph Hellwig
2020-07-21 16:27 ` [PATCH 03/24] fs: push the getname from do_rmdir into the callers Christoph Hellwig
2020-07-21 16:27 ` [PATCH 04/24] devtmpfs: open code do_mount Christoph Hellwig
2020-07-21 16:27 ` [PATCH 05/24] devtmpfs: open code ksys_chdir and ksys_chroot Christoph Hellwig
2020-07-21 16:49 ` Linus Torvalds
2020-07-21 17:16 ` Al Viro
2020-07-21 18:26 ` Christoph Hellwig
2020-07-21 16:28 ` [PATCH 06/24] md: open code vfs_stat in md_setup_drive Christoph Hellwig
2020-07-21 16:55 ` Al Viro [this message]
2020-07-21 18:27 ` Christoph Hellwig
2020-07-22 7:44 ` Al Viro
2020-07-22 14:05 ` Christoph Hellwig
2020-07-21 16:28 ` [PATCH 07/24] init: initialize ramdisk_execute_command at compile time Christoph Hellwig
2020-07-21 16:28 ` [PATCH 08/24] init: move the prepare_namespace prototype to init/do_mounts.h Christoph Hellwig
2020-07-21 16:28 ` [PATCH 09/24] init: mark create_dev as __init Christoph Hellwig
2020-07-21 16:28 ` [PATCH 10/24] init: open code ksys_umount in handle_initrd Christoph Hellwig
2020-07-21 16:28 ` [PATCH 11/24] init: open code do_utimes in do_utime Christoph Hellwig
2020-07-21 16:28 ` [PATCH 12/24] init: add an init_mount helper Christoph Hellwig
2020-07-21 16:58 ` Al Viro
2020-07-21 16:28 ` [PATCH 13/24] init: add an init_unlink helper Christoph Hellwig
2020-07-21 17:12 ` Al Viro
2020-07-21 16:28 ` [PATCH 14/24] init: add an init_rmdir helper Christoph Hellwig
2020-07-21 16:28 ` [PATCH 15/24] init: add an init_chdir helper Christoph Hellwig
2020-07-21 16:28 ` [PATCH 16/24] init: add an init_chroot helper Christoph Hellwig
2020-07-21 17:10 ` Al Viro
2020-07-21 16:28 ` [PATCH 17/24] init: add an init_chown helper Christoph Hellwig
2020-07-21 16:28 ` [PATCH 18/24] init: add an init_chmod helper Christoph Hellwig
2020-07-21 16:28 ` [PATCH 19/24] init: add an init_eaccess helper Christoph Hellwig
2020-07-21 16:28 ` [PATCH 20/24] init: add an init_link helper Christoph Hellwig
2020-07-21 16:28 ` [PATCH 21/24] init: add an init_symlink helper Christoph Hellwig
2020-07-21 17:00 ` Al Viro
2020-07-21 16:28 ` [PATCH 22/24] init: add an init_mkdir helper Christoph Hellwig
2020-07-21 16:28 ` [PATCH 23/24] init: add an init_mknod helper Christoph Hellwig
2020-07-21 17:02 ` Al Viro
2020-07-21 16:28 ` [PATCH 24/24] init: add an init_lstat helper 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=20200721165539.GT2786714@ZenIV.linux.org.uk \
--to=viro@zeniv.linux.org.uk \
--cc=gregkh@linuxfoundation.org \
--cc=hch@lst.de \
--cc=linux-api@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-raid@vger.kernel.org \
--cc=rafael@kernel.org \
--cc=torvalds@linux-foundation.org \
/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).