Linux-CIFS Archive on lore.kernel.org
 help / color / Atom feed
From: 'Christoph Hellwig' <hch@lst.de>
To: David Laight <David.Laight@ACULAB.COM>
Cc: 'Christoph Hellwig' <hch@lst.de>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
	Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	Vlad Yasevich <vyasevich@gmail.com>,
	Neil Horman <nhorman@tuxdriver.com>,
	Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
	Jon Maloy <jmaloy@redhat.com>, Ying Xue <ying.xue@windriver.com>,
	"drbd-dev@lists.linbit.com" <drbd-dev@lists.linbit.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
	"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
	"target-devel@vger.kernel.org" <target-devel@vger.kernel.org>,
	"linux-afs@lists.infradead.org" <linux-afs@lists.infradead.org>,
	"linux-cifs@vger.kernel.org" <linux-cifs@vger.kernel.org>,
	"cluster-devel@redhat.com" <cluster-devel@redhat.com>,
	"ocfs2-devel@oss.oracle.com" <ocfs2-devel@oss.oracle.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-sctp@vger.kernel.org" <linux-sctp@vger.kernel.org>,
	"ceph-devel@vger.kernel.org" <ceph-devel@vger.kernel.org>,
	"rds-devel@oss.oracle.com" <rds-devel@oss.oracle.com>,
	"linux-nfs@vger.kernel.org" <linux-nfs@vger.kernel.org>
Subject: Re: remove kernel_setsockopt and kernel_getsockopt v2
Date: Thu, 21 May 2020 11:11:50 +0200
Message-ID: <20200521091150.GA8401@lst.de> (raw)
In-Reply-To: <138a17dfff244c089b95f129e4ea2f66@AcuMS.aculab.com>

On Thu, May 21, 2020 at 08:01:33AM +0000, David Laight wrote:
> How much does this increase the kernel code by?

 44 files changed, 660 insertions(+), 843 deletions(-)


> You are also replicating a lot of code making it more
> difficult to maintain.

No, I specifically don't.

> I don't think the performance of an socket option code
> really matters - it is usually done once when a socket
> is initialised and the other costs of establishing a
> connection will dominate.
> 
> Pulling the user copies outside the [gs]etsocksopt switch
> statement not only reduces the code size (source and object)
> and trivially allows kernel_[sg]sockopt() to me added to
> the list of socket calls.
> 
> It probably isn't possible to pull the usercopies right
> out into the syscall wrapper because of some broken
> requests.

Please read through the previous discussion of the rationale and the
options.  We've been there before.

> I worried about whether getsockopt() should read the entire
> user buffer first. SCTP needs the some of it often (including a
> sockaddr_storage in one case), TCP needs it once.
> However the cost of reading a few words is small, and a big
> buffer probably needs setting to avoid leaking kernel
> memory if the structure has holes or fields that don't get set.
> Reading from userspace solves both issues.

As mention in the thread on the last series:  That was my first idea, but
we have way to many sockopts, especially in obscure protocols that just
hard code the size.  The chance of breaking userspace in a way that can't
be fixed without going back to passing user pointers to get/setsockopt
is way to high to commit to such a change unfortunately.

  reply index

Thread overview: 50+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-20 19:54 Christoph Hellwig
2020-05-20 19:54 ` [PATCH 01/33] dlm: use the tcp version of accept_from_sock for sctp as well Christoph Hellwig
2020-05-20 19:54 ` [PATCH 02/33] net: remove kernel_getsockopt Christoph Hellwig
2020-05-20 19:54 ` [PATCH 03/33] net: add sock_set_reuseaddr Christoph Hellwig
2020-05-20 19:54 ` [PATCH 04/33] net: add sock_no_linger Christoph Hellwig
2020-05-20 19:54 ` [PATCH 05/33] net: add sock_set_priority Christoph Hellwig
2020-05-20 19:54 ` [PATCH 06/33] net: add sock_set_sndtimeo Christoph Hellwig
2020-05-20 19:54 ` [PATCH 07/33] net: add sock_bindtoindex Christoph Hellwig
2020-05-20 19:54 ` [PATCH 08/33] net: add sock_enable_timestamps Christoph Hellwig
2020-05-20 19:54 ` [PATCH 09/33] net: add sock_set_keepalive Christoph Hellwig
2020-05-20 19:54 ` [PATCH 10/33] net: add sock_set_rcvbuf Christoph Hellwig
2020-05-20 19:54 ` [PATCH 11/33] net: add sock_set_reuseport Christoph Hellwig
2020-05-20 19:54 ` [PATCH 12/33] tcp: add tcp_sock_set_cork Christoph Hellwig
2020-05-20 19:54 ` [PATCH 13/33] tcp: add tcp_sock_set_nodelay Christoph Hellwig
2020-05-20 19:54 ` [PATCH 14/33] tcp: add tcp_sock_set_quickack Christoph Hellwig
2020-05-20 19:54 ` [PATCH 15/33] tcp: add tcp_sock_set_syncnt Christoph Hellwig
2020-05-20 19:54 ` [PATCH 16/33] tcp: add tcp_sock_set_user_timeout Christoph Hellwig
2020-05-20 19:54 ` [PATCH 17/33] tcp: add tcp_sock_set_keepidle Christoph Hellwig
2020-05-20 19:54 ` [PATCH 18/33] tcp: add tcp_sock_set_keepintvl Christoph Hellwig
2020-05-20 19:54 ` [PATCH 19/33] tcp: add tcp_sock_set_keepcnt Christoph Hellwig
2020-05-20 19:54 ` [PATCH 20/33] ipv4: add ip_sock_set_tos Christoph Hellwig
2020-05-20 19:54 ` [PATCH 21/33] ipv4: add ip_sock_set_freebind Christoph Hellwig
2020-05-20 19:54 ` [PATCH 22/33] ipv4: add ip_sock_set_recverr Christoph Hellwig
2020-05-20 19:54 ` [PATCH 23/33] ipv4: add ip_sock_set_mtu_discover Christoph Hellwig
2020-05-20 19:55 ` [PATCH 24/33] ipv4: add ip_sock_set_pktinfo Christoph Hellwig
2020-05-20 19:55 ` [PATCH 25/33] ipv6: add ip6_sock_set_v6only Christoph Hellwig
2020-05-20 19:55 ` [PATCH 26/33] ipv6: add ip6_sock_set_recverr Christoph Hellwig
2020-05-20 19:55 ` [PATCH 27/33] ipv6: add ip6_sock_set_addr_preferences Christoph Hellwig
2020-05-20 19:55 ` [PATCH 28/33] ipv6: add ip6_sock_set_recvpktinfo Christoph Hellwig
2020-05-20 19:55 ` [PATCH 29/33] rxrpc: add rxrpc_sock_set_min_security_level Christoph Hellwig
2020-05-20 19:55 ` [PATCH 30/33] tipc: call tsk_set_importance from tipc_topsrv_create_listener Christoph Hellwig
2020-05-20 19:55 ` [PATCH 31/33] sctp: add sctp_sock_set_nodelay Christoph Hellwig
2020-05-20 23:10   ` Marcelo Ricardo Leitner
2020-05-20 23:23     ` David Miller
2020-05-20 23:39       ` Marcelo Ricardo Leitner
2020-05-21  8:34         ` Christoph Hellwig
2020-05-21  9:06           ` David Laight
2020-05-21  9:08             ` 'Christoph Hellwig'
2020-05-21 13:33           ` Marcelo Ricardo Leitner
2020-05-21 13:57             ` Christoph Hellwig
2020-05-20 19:55 ` [PATCH 32/33] net: add a new bind_add method Christoph Hellwig
2020-05-20 23:00   ` Marcelo Ricardo Leitner
2020-05-21  8:42     ` Christoph Hellwig
2020-05-21 13:54       ` Marcelo Ricardo Leitner
2020-05-20 19:55 ` [PATCH 33/33] net: remove kernel_setsockopt Christoph Hellwig
2020-05-21  7:44 ` [PATCH 29/33] rxrpc: add rxrpc_sock_set_min_security_level David Howells
2020-05-21  8:01 ` remove kernel_setsockopt and kernel_getsockopt v2 David Laight
2020-05-21  9:11   ` 'Christoph Hellwig' [this message]
2020-05-21 10:46     ` David Laight
2020-05-23  7:23 ` 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=20200521091150.GA8401@lst.de \
    --to=hch@lst.de \
    --cc=David.Laight@ACULAB.COM \
    --cc=ceph-devel@vger.kernel.org \
    --cc=cluster-devel@redhat.com \
    --cc=davem@davemloft.net \
    --cc=drbd-dev@lists.linbit.com \
    --cc=edumazet@google.com \
    --cc=jmaloy@redhat.com \
    --cc=kuba@kernel.org \
    --cc=kuznet@ms2.inr.ac.ru \
    --cc=linux-afs@lists.infradead.org \
    --cc=linux-cifs@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nfs@vger.kernel.org \
    --cc=linux-nvme@lists.infradead.org \
    --cc=linux-rdma@vger.kernel.org \
    --cc=linux-sctp@vger.kernel.org \
    --cc=marcelo.leitner@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=nhorman@tuxdriver.com \
    --cc=ocfs2-devel@oss.oracle.com \
    --cc=rds-devel@oss.oracle.com \
    --cc=target-devel@vger.kernel.org \
    --cc=vyasevich@gmail.com \
    --cc=ying.xue@windriver.com \
    --cc=yoshfuji@linux-ipv6.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

Linux-CIFS Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-cifs/0 linux-cifs/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-cifs linux-cifs/ https://lore.kernel.org/linux-cifs \
		linux-cifs@vger.kernel.org
	public-inbox-index linux-cifs

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-cifs


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git