From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C0A1C433E0 for ; Fri, 29 May 2020 22:00:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0B3A720707 for ; Fri, 29 May 2020 22:00:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="I087R3NU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728253AbgE2WAJ (ORCPT ); Fri, 29 May 2020 18:00:09 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:27611 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726975AbgE2WAI (ORCPT ); Fri, 29 May 2020 18:00:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590789606; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=pxbvmVbl9lsruKM4AA1eWb8CAia0DHVSFuL5O/ctfrI=; b=I087R3NUFu3cKPAm6Vv+gFHnFyyz8GsDkO1CKLMbHquHuakL8rmYiOmCUaI7OetHOe6ZPi FPqhxtCmdzrx4ZmBhy3TexYnmZfWsZhsEXY5NsVJvKKsvOtmkRRCWhPUB6wGuJld1rYjEK VQhXCtWa7Nx6EMCMbqUN2Q4dEWLeRiE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-298-ufnsmF08M5m8DCBHuapQYg-1; Fri, 29 May 2020 18:00:04 -0400 X-MC-Unique: ufnsmF08M5m8DCBHuapQYg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 806BD18A8220; Fri, 29 May 2020 22:00:02 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-112-138.rdu2.redhat.com [10.10.112.138]) by smtp.corp.redhat.com (Postfix) with ESMTP id 968BB5C1B5; Fri, 29 May 2020 22:00:00 +0000 (UTC) Subject: [PATCH 00/27] afs: Improvements From: David Howells To: linux-afs@lists.infradead.org Cc: linux-ext4@vger.kernel.org, Konstantin Khlebnikov , Jeffrey Altman , Dave Botsch , dhowells@redhat.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 29 May 2020 22:59:59 +0100 Message-ID: <159078959973.679399.15496997680826127470.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.22 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Here's a set of patches to make a number of improvements to the AFS driver: (1) Improve callback (ie. third party change notification) processing by: (a) Relying more on the fact we're doing this under RCU and by using fewer locks. This involves making the inode hash table RCU safe and providing some RCU-safe accessor functions. The search can then be done without taking the inode_hash_lock. Care must be taken because the object may be being deleted and no wait is made. This is also used to improve Ext4's time updating. Konstantin Khlebnikov said "For now, I've plugged this issue with try-lock in ext4 lazy time update. This solution is much better." (b) Moving to keeping volumes in a tree indexed by volume ID rather than a flat list. (c) Making the server and volume records logically part of the cell. This means that a server record now points directly at the cell and the tree of volumes is there. This removes an N:M mapping table, simplifying things. (2) Improve keeping NAT or firewall channels open for the server callbacks to reach the client by actively polling the fileserver on a timed basis, instead of only doing it when we have an operation to process. (3) Improving detection of delayed or lost callbacks by including the parent directory in the list of file IDs to be queried when doing a bulk status fetch from lookup. We can then check to see if our copy of the directory has changed under us without us getting notified. (4) Determine aliasing of cells (such as a cell that is pointed to be a DNS alias). This allows us to avoid having ambiguity due to apparently different cells using the same volume and file servers. (5) Improve the fileserver rotation to do more probing when it detects that all of the addresses to a server are listed as non-responsive. It's possible that an address that previously stopped responding has become responsive again. Beyond that, lay some foundations for making some calls asynchronous: (1) Turn the fileserver cursor struct into a general operation struct and hang the parameters off of that rather than keeping them in local variables and hang results off of that rather than the call struct. (2) Implement some general operation handling code and simplify the callers of operations that affect a volume or a volume component (such as a file). Most of the operation is now done by core code. (3) Operations are supplied with a table of operations to issue different variants of RPCs and to manage the completion, where all the required data is held in the operation object, thereby allowing these to be called from a workqueue. (4) Put the standard "if (begin), while(select), call op, end" sequence into a canned function that just emulates the current behaviour for now. There are also some fixes interspersed: (1) Don't let the EACCES from ICMP6 mapping reach the user as such, since it's confusing as to whether it's a filesystem error. Convert it to EHOSTUNREACH. (2) Don't use the epoch value acquired through probing a server. If we have two servers with the same UUID but in different cells, it's hard to draw conclusions from them having different epoch values. (3) Don't interpret the argument to the CB.ProbeUuid RPC as a fileserver UUID and look up a fileserver from it. (4) Deal with servers in different cells having the same UUIDs. In the event that a CB.InitCallBackState3 RPC is received, we have to break the callback promises for every server record matching that UUID. (5) Don't let afs_statfs return values that go below 0. (6) Don't use running fileserver probe state to make server selection and address selection decisions on. Only make decisions on final state as the running state is cleared at the start of probing. The patches are here: http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=afs-next David --- David Howells (1): afs: Adjust the fileserver rotation algorithm to reprobe/retry more quickly fs/afs/Makefile | 2 + fs/afs/afs.h | 3 +- fs/afs/afs_vl.h | 1 + fs/afs/callback.c | 345 ++++-------- fs/afs/cell.c | 10 +- fs/afs/cmservice.c | 67 +-- fs/afs/dir.c | 1253 ++++++++++++++++++++---------------------- fs/afs/dir_silly.c | 190 +++---- fs/afs/dynroot.c | 93 ++++ fs/afs/file.c | 62 ++- fs/afs/flock.c | 114 ++-- fs/afs/fs_operation.c | 239 ++++++++ fs/afs/fs_probe.c | 339 +++++++++--- fs/afs/fsclient.c | 1295 +++++++++++++++++--------------------------- fs/afs/inode.c | 491 ++++++++--------- fs/afs/internal.h | 523 ++++++++++-------- fs/afs/main.c | 6 +- fs/afs/proc.c | 42 +- fs/afs/protocol_yfs.h | 2 +- fs/afs/rotate.c | 443 ++++++--------- fs/afs/rxrpc.c | 45 +- fs/afs/security.c | 8 +- fs/afs/server.c | 299 ++++++---- fs/afs/server_list.c | 40 +- fs/afs/super.c | 107 ++-- fs/afs/vl_alias.c | 384 +++++++++++++ fs/afs/vl_rotate.c | 4 + fs/afs/vlclient.c | 146 ++++- fs/afs/volume.c | 152 ++++-- fs/afs/write.c | 148 +++-- fs/afs/xattr.c | 300 +++++----- fs/afs/yfsclient.c | 914 +++++++++++++------------------ fs/ext4/inode.c | 44 +- fs/inode.c | 173 +++++- include/linux/fs.h | 3 + include/trace/events/afs.h | 111 +++- net/rxrpc/peer_event.c | 3 + net/rxrpc/proc.c | 6 +- 38 files changed, 4484 insertions(+), 3923 deletions(-) create mode 100644 fs/afs/fs_operation.c create mode 100644 fs/afs/vl_alias.c