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=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 0AF5BC07E9C for ; Wed, 7 Jul 2021 12:05:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E943D61C99 for ; Wed, 7 Jul 2021 12:05:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231494AbhGGMHv (ORCPT ); Wed, 7 Jul 2021 08:07:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:44416 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231462AbhGGMHv (ORCPT ); Wed, 7 Jul 2021 08:07:51 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7C50761C9A; Wed, 7 Jul 2021 12:05:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625659511; bh=ZeEK/ANtvXr8EHIm8i6aKLUByrXcuhCmz28gAy3bRRA=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=JmICjisPm4NaoBdFpON77MdX4Eqy2ypLmKJ75mCIW7LkJNfMYj8TstFSN/j7NBmzg /X5BGd3hURpWc2wwIyk92IRVRBgwgELh2iCHwdHI5mCI2YIYAzAOzF31usVnQHWruf ym0NCdZC/1QzNiN07RGsCKRV8l2IA5TWqeJ0iO6QWZlp+P0DSYIxuOsPH5Pwq9ABMD HONbG4hhcfr/FoCKlYGGMzb1wlSbvegMUCd1K5SejjBMznEUNb3ROKVaz2b0TP44xu 8pLimX4Ws19o9Iq6YMDDjPXGHNztzZRJqNVnM4SryAY+CtC7EHBDKDVkvhLXhlyB/0 B7JNZX8JQLbqg== Message-ID: Subject: Re: [RFC PATCH v7 05/24] ceph: preallocate inode for ops that may create one From: Jeff Layton To: Xiubo Li , ceph-devel@vger.kernel.org Cc: lhenriques@suse.de, linux-fsdevel@vger.kernel.org, linux-fscrypt@vger.kernel.org, dhowells@redhat.com Date: Wed, 07 Jul 2021 08:05:09 -0400 In-Reply-To: <83dcbc5c-7a87-b6cd-b364-2ca4aa5bd440@redhat.com> References: <20210625135834.12934-1-jlayton@kernel.org> <20210625135834.12934-6-jlayton@kernel.org> <83dcbc5c-7a87-b6cd-b364-2ca4aa5bd440@redhat.com> Content-Type: text/plain; charset="ISO-8859-15" User-Agent: Evolution 3.40.2 (3.40.2-1.fc34) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org On Wed, 2021-07-07 at 11:37 +0800, Xiubo Li wrote: > On 6/25/21 9:58 PM, Jeff Layton wrote: > > When creating a new inode, we need to determine the crypto context > > before we can transmit the RPC. The fscrypt API has a routine for getting > > a crypto context before a create occurs, but it requires an inode. > > > > Change the ceph code to preallocate an inode in advance of a create of > > any sort (open(), mknod(), symlink(), etc). Move the existing code that > > generates the ACL and SELinux blobs into this routine since that's > > mostly common across all the different codepaths. > > > > In most cases, we just want to allow ceph_fill_trace to use that inode > > after the reply comes in, so add a new field to the MDS request for it > > (r_new_inode). > > > > The async create codepath is a bit different though. In that case, we > > want to hash the inode in advance of the RPC so that it can be used > > before the reply comes in. If the call subsequently fails with > > -EJUKEBOX, then just put the references and clean up the as_ctx. Note > > that with this change, we now need to regenerate the as_ctx when this > > occurs, but it's quite rare for it to happen. > > > > Signed-off-by: Jeff Layton > > --- > > fs/ceph/dir.c | 70 ++++++++++++++++++++----------------- > > fs/ceph/file.c | 62 ++++++++++++++++++++------------- > > fs/ceph/inode.c | 82 ++++++++++++++++++++++++++++++++++++++++---- > > fs/ceph/mds_client.c | 3 +- > > fs/ceph/mds_client.h | 1 + > > fs/ceph/super.h | 7 +++- > > 6 files changed, 160 insertions(+), 65 deletions(-) > > > [...] > > > diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c > > index eb562e259347..f62785e4dbcb 100644 > > --- a/fs/ceph/inode.c > > +++ b/fs/ceph/inode.c > > @@ -52,17 +52,85 @@ static int ceph_set_ino_cb(struct inode *inode, void *data) > > return 0; > > } > > > > -struct inode *ceph_get_inode(struct super_block *sb, struct ceph_vino vino) > > +/** > > + * ceph_new_inode - allocate a new inode in advance of an expected create > > + * @dir: parent directory for new inode > > + * @dentry: dentry that may eventually point to new inode > > + * @mode: mode of new inode > > + * @as_ctx: pointer to inherited security context > > + * > > + * Allocate a new inode in advance of an operation to create a new inode. > > + * This allocates the inode and sets up the acl_sec_ctx with appropriate > > + * info for the new inode. > > + * > > + * Returns a pointer to the new inode or an ERR_PTR. > > + */ > > +struct inode *ceph_new_inode(struct inode *dir, struct dentry *dentry, > > + umode_t *mode, struct ceph_acl_sec_ctx *as_ctx) > > +{ > > + int err; > > + struct inode *inode; > > + > > + inode = new_inode_pseudo(dir->i_sb); > > + if (!inode) > > + return ERR_PTR(-ENOMEM); > > + > > + if (!S_ISLNK(*mode)) { > > + err = ceph_pre_init_acls(dir, mode, as_ctx); > > + if (err < 0) > > + goto out_err; > > + } > > + > > + err = ceph_security_init_secctx(dentry, *mode, as_ctx); > > + if (err < 0) > > + goto out_err; > > + > > + inode->i_state = 0; > > + inode->i_mode = *mode; > > + return inode; > > +out_err: > > + iput(inode); > > + return ERR_PTR(err); > > +} > > + > > +void ceph_as_ctx_to_req(struct ceph_mds_request *req, struct ceph_acl_sec_ctx *as_ctx) > > +{ > > + if (as_ctx->pagelist) { > > + req->r_pagelist = as_ctx->pagelist; > > + as_ctx->pagelist = NULL; > > + } > > +} > > + > > +/** > > + * ceph_get_inode - find or create/hash a new inode > > + * @sb: superblock to search and allocate in > > + * @vino: vino to search for > > + * @newino: optional new inode to insert if one isn't found (may be NULL) > > + * > > + * Search for or insert a new inode into the hash for the given vino, and return a > > + * reference to it. If new is non-NULL, its reference is consumed. > > + */ > > +struct inode *ceph_get_inode(struct super_block *sb, struct ceph_vino vino, struct inode *newino) > > { > > struct inode *inode; > > > > if (ceph_vino_is_reserved(vino)) > > return ERR_PTR(-EREMOTEIO); > > > > - inode = iget5_locked(sb, (unsigned long)vino.ino, ceph_ino_compare, > > - ceph_set_ino_cb, &vino); > > - if (!inode) > > + if (newino) { > > + inode = inode_insert5(newino, (unsigned long)vino.ino, ceph_ino_compare, > > + ceph_set_ino_cb, &vino); > > + if (inode != newino) > > + iput(newino); > > + } else { > > + inode = iget5_locked(sb, (unsigned long)vino.ino, ceph_ino_compare, > > + ceph_set_ino_cb, &vino); > > + } > > + > > + if (!inode) { > > + dout("No inode found for %llx.%llx\n", vino.ino, vino.snap); > > return ERR_PTR(-ENOMEM); > > + } > > > > dout("get_inode on %llu=%llx.%llx got %p new %d\n", ceph_present_inode(inode), > > ceph_vinop(inode), inode, !!(inode->i_state & I_NEW)); > > @@ -78,7 +146,7 @@ struct inode *ceph_get_snapdir(struct inode *parent) > > .ino = ceph_ino(parent), > > .snap = CEPH_SNAPDIR, > > }; > > - struct inode *inode = ceph_get_inode(parent->i_sb, vino); > > + struct inode *inode = ceph_get_inode(parent->i_sb, vino, NULL); > > struct ceph_inode_info *ci = ceph_inode(inode); > > > > if (IS_ERR(inode)) > > Should we always check this just before using it before 'struct > ceph_inode_info *ci = ceph_inode(inode);' ? > > But it seems the 'ceph_inode()' won't introduce any issue here. > > Thanks, > Yeah, it's just doing pointer math. If it turns out to be an error, it'll exit before it ever dereferences "ci". > > @@ -1546,7 +1614,7 @@ static int readdir_prepopulate_inodes_only(struct ceph_mds_request *req, > > vino.ino = le64_to_cpu(rde->inode.in->ino); > > vino.snap = le64_to_cpu(rde->inode.in->snapid); > > > > - in = ceph_get_inode(req->r_dentry->d_sb, vino); > > + in = ceph_get_inode(req->r_dentry->d_sb, vino, NULL); > > if (IS_ERR(in)) { > > err = PTR_ERR(in); > > dout("new_inode badness got %d\n", err); > > @@ -1748,7 +1816,7 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req, > > if (d_really_is_positive(dn)) { > > in = d_inode(dn); > > } else { > > - in = ceph_get_inode(parent->d_sb, tvino); > > + in = ceph_get_inode(parent->d_sb, tvino, NULL); > > if (IS_ERR(in)) { > > dout("new_inode badness\n"); > > d_drop(dn); > [...] > -- Jeff Layton