From patchwork Wed Apr 20 18:28:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820662 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BA6DC433EF for ; Wed, 20 Apr 2022 18:28:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381484AbiDTSbc (ORCPT ); Wed, 20 Apr 2022 14:31:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245374AbiDTSba (ORCPT ); Wed, 20 Apr 2022 14:31:30 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7785B1F60E; Wed, 20 Apr 2022 11:28:43 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 143C861B60; Wed, 20 Apr 2022 18:28:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C341C385A1; Wed, 20 Apr 2022 18:28:42 +0000 (UTC) Subject: [PATCH RFC 1/8] NFSD: Clean up nfsd3_proc_create() From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:28:41 -0400 Message-ID: <165047932133.1829.5575048750237048079.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org As near as I can tell, mode bit masking and setting S_IFREG is already done by do_nfsd_create() and vfs_create(). The NFSv4 path (do_open_lookup), for example, does not bother with this special processing. Signed-off-by: Chuck Lever --- fs/nfsd/nfs3proc.c | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-) diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index 936eebd4c56d..981a2a71c5af 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -229,8 +229,7 @@ nfsd3_proc_create(struct svc_rqst *rqstp) { struct nfsd3_createargs *argp = rqstp->rq_argp; struct nfsd3_diropres *resp = rqstp->rq_resp; - svc_fh *dirfhp, *newfhp = NULL; - struct iattr *attr; + svc_fh *dirfhp, *newfhp; dprintk("nfsd: CREATE(3) %s %.*s\n", SVCFH_fmt(&argp->fh), @@ -239,20 +238,9 @@ nfsd3_proc_create(struct svc_rqst *rqstp) dirfhp = fh_copy(&resp->dirfh, &argp->fh); newfhp = fh_init(&resp->fh, NFS3_FHSIZE); - attr = &argp->attrs; - - /* Unfudge the mode bits */ - attr->ia_mode &= ~S_IFMT; - if (!(attr->ia_valid & ATTR_MODE)) { - attr->ia_valid |= ATTR_MODE; - attr->ia_mode = S_IFREG; - } else { - attr->ia_mode = (attr->ia_mode & ~S_IFMT) | S_IFREG; - } - /* Now create the file and set attributes */ resp->status = do_nfsd_create(rqstp, dirfhp, argp->name, argp->len, - attr, newfhp, argp->createmode, + &argp->attrs, newfhp, argp->createmode, (u32 *)argp->verf, NULL, NULL); return rpc_success; } From patchwork Wed Apr 20 18:28:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820663 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B94F4C433F5 for ; Wed, 20 Apr 2022 18:28:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381470AbiDTSbl (ORCPT ); Wed, 20 Apr 2022 14:31:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245374AbiDTSbg (ORCPT ); Wed, 20 Apr 2022 14:31:36 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C273C369F7; Wed, 20 Apr 2022 11:28:49 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5F30F61B60; Wed, 20 Apr 2022 18:28:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A3FB4C385A1; Wed, 20 Apr 2022 18:28:48 +0000 (UTC) Subject: [PATCH RFC 2/8] NFSD: Avoid calling fh_drop_write() twice in do_nfsd_create() From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:28:47 -0400 Message-ID: <165047932768.1829.13086014644043363180.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Clean up: The "out" label already invokes fh_drop_write(). Note that fh_drop_write() is already careful not to invoke mnt_drop_write() if either it has already been done or there is nothing to drop. Therefore no change in behavior is expected. Signed-off-by: Chuck Lever --- fs/nfsd/vfs.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index c22ad0532e8e..97fee9b33490 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1485,7 +1485,6 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, case NFS3_CREATE_GUARDED: err = nfserr_exist; } - fh_drop_write(fhp); goto out; } @@ -1493,10 +1492,8 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, iap->ia_mode &= ~current_umask(); host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true); - if (host_err < 0) { - fh_drop_write(fhp); + if (host_err < 0) goto out_nfserr; - } if (created) *created = true; From patchwork Wed Apr 20 18:28:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820664 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A96F1C433F5 for ; Wed, 20 Apr 2022 18:29:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245374AbiDTSbn (ORCPT ); Wed, 20 Apr 2022 14:31:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52782 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1381490AbiDTSbm (ORCPT ); Wed, 20 Apr 2022 14:31:42 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13D0238BFF; Wed, 20 Apr 2022 11:28:56 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A37A761B1F; Wed, 20 Apr 2022 18:28:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9BC9C385A0; Wed, 20 Apr 2022 18:28:54 +0000 (UTC) Subject: [PATCH RFC 3/8] NFSD: Refactor nfsd_create_setattr() From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:28:53 -0400 Message-ID: <165047933398.1829.4730484936887112886.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org I'd like to move do_nfsd_create() out of vfs.c. Therefore nfsd_create_setattr() needs to be made publicly visible. Note that both call sites in vfs.c commit both the new object and its parent directory, so just combine those common metadata commits into nfsd_create_setattr(). Signed-off-by: Chuck Lever --- fs/nfsd/vfs.c | 79 ++++++++++++++++++++++++++++++--------------------------- fs/nfsd/vfs.h | 2 + 2 files changed, 44 insertions(+), 37 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 97fee9b33490..ed58f7d46730 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1187,14 +1187,26 @@ nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp, u64 offset, return err; } -static __be32 -nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp, - struct iattr *iap) +/** + * nfsd_create_setattr - Set a created file's attributes + * @rqstp: RPC transaction being executed + * @fhp: NFS filehandle of parent directory + * @resfhp: NFS filehandle of new object + * @iap: requested attributes of new object + * + * Returns nfs_ok on success, or an nfsstat in network byte order. + */ +__be32 +nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, + struct svc_fh *resfhp, struct iattr *iap) { + __be32 status; + /* - * Mode has already been set earlier in create: + * Mode has already been set by file creation. */ iap->ia_valid &= ~ATTR_MODE; + /* * Setting uid/gid works only for root. Irix appears to * send along the gid on create when it tries to implement @@ -1202,10 +1214,31 @@ nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp, */ if (!uid_eq(current_fsuid(), GLOBAL_ROOT_UID)) iap->ia_valid &= ~(ATTR_UID|ATTR_GID); + + /* + * Callers expect new file metadata to be committed even + * if the attributes have not changed. + */ if (iap->ia_valid) - return nfsd_setattr(rqstp, resfhp, iap, 0, (time64_t)0); - /* Callers expect file metadata to be committed here */ - return nfserrno(commit_metadata(resfhp)); + status = nfsd_setattr(rqstp, resfhp, iap, 0, (time64_t)0); + else + status = nfserrno(commit_metadata(resfhp)); + + /* + * Transactional filesystems had a chance to commit changes + * for both parent and child simultaneously making the + * following commit_metadata a noop in many cases. + */ + if (!status) + status = nfserrno(commit_metadata(fhp)); + + /* + * Update the new filehandle to pick up the new attributes. + */ + if (!status) + status = fh_update(resfhp); + + return status; } /* HPUX client sometimes creates a file in mode 000, and sets size to 0. @@ -1232,7 +1265,6 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp, struct dentry *dentry, *dchild; struct inode *dirp; __be32 err; - __be32 err2; int host_err; dentry = fhp->fh_dentry; @@ -1305,22 +1337,8 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp, if (host_err < 0) goto out_nfserr; - err = nfsd_create_setattr(rqstp, resfhp, iap); + err = nfsd_create_setattr(rqstp, fhp, resfhp, iap); - /* - * nfsd_create_setattr already committed the child. Transactional - * filesystems had a chance to commit changes for both parent and - * child simultaneously making the following commit_metadata a - * noop. - */ - err2 = nfserrno(commit_metadata(fhp)); - if (err2) - err = err2; - /* - * Update the file handle to get the new inode info. - */ - if (!err) - err = fh_update(resfhp); out: dput(dchild); return err; @@ -1511,20 +1529,7 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, } set_attr: - err = nfsd_create_setattr(rqstp, resfhp, iap); - - /* - * nfsd_create_setattr already committed the child - * (and possibly also the parent). - */ - if (!err) - err = nfserrno(commit_metadata(fhp)); - - /* - * Update the filehandle to get the new inode info. - */ - if (!err) - err = fh_update(resfhp); + err = nfsd_create_setattr(rqstp, fhp, resfhp, iap); out: fh_unlock(fhp); diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h index ccb87b2864f6..1f32a83456b0 100644 --- a/fs/nfsd/vfs.h +++ b/fs/nfsd/vfs.h @@ -69,6 +69,8 @@ __be32 nfsd_create(struct svc_rqst *, struct svc_fh *, char *name, int len, struct iattr *attrs, int type, dev_t rdev, struct svc_fh *res); __be32 nfsd_access(struct svc_rqst *, struct svc_fh *, u32 *, u32 *); +__be32 nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, + struct svc_fh *resfhp, struct iattr *iap); __be32 do_nfsd_create(struct svc_rqst *, struct svc_fh *, char *name, int len, struct iattr *attrs, struct svc_fh *res, int createmode, From patchwork Wed Apr 20 18:29:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820665 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5DF1C433EF for ; Wed, 20 Apr 2022 18:29:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381496AbiDTSby (ORCPT ); Wed, 20 Apr 2022 14:31:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238853AbiDTSbt (ORCPT ); Wed, 20 Apr 2022 14:31:49 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7963B1F60E; Wed, 20 Apr 2022 11:29:02 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 156D761B60; Wed, 20 Apr 2022 18:29:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5248DC385A8; Wed, 20 Apr 2022 18:29:01 +0000 (UTC) Subject: [PATCH RFC 4/8] NFSD: Refactor NFSv3 CREATE From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:29:00 -0400 Message-ID: <165047934027.1829.4170855794285748158.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org The NFSv3 CREATE and NFSv4 OPEN(CREATE) use cases are about to diverge such that it makes sense to split do_nfsd_create() into one version for NFSv3 and one for NFSv4. As a first step, copy do_nfsd_create() to nfs3proc.c and remove NFSv4-specific logic. One immediate legibility benefit is that the logic for handling NFSv3 createhow is now quite straightforward. NFSv4 createhow has some subtleties that IMO do not belong in generic code. Signed-off-by: Chuck Lever --- fs/nfsd/nfs3proc.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 121 insertions(+), 6 deletions(-) diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index 981a2a71c5af..981a3a7a6e16 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -8,6 +8,7 @@ #include #include #include +#include #include "cache.h" #include "xdr3.h" @@ -220,10 +221,126 @@ nfsd3_proc_write(struct svc_rqst *rqstp) } /* - * With NFSv3, CREATE processing is a lot easier than with NFSv2. - * At least in theory; we'll see how it fares in practice when the - * first reports about SunOS compatibility problems start to pour in... + * Implement NFSv3's unchecked, guarded, and exclusive CREATE + * semantics for regular files. Except for the created file, + * this operation is stateless on the server. + * + * Upon return, caller must release @fhp and @resfhp. */ +static __be32 +nfsd3_create_file(struct svc_rqst *rqstp, struct svc_fh *fhp, + struct svc_fh *resfhp, struct nfsd3_createargs *argp) +{ + struct iattr *iap = &argp->attrs; + struct dentry *parent, *child; + __u32 v_mtime, v_atime; + struct inode *inode; + __be32 status; + int host_err; + + if (isdotent(argp->name, argp->len)) + return nfserr_exist; + if (!(iap->ia_valid & ATTR_MODE)) + iap->ia_mode = 0; + + status = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC); + if (status != nfs_ok) + return status; + + parent = fhp->fh_dentry; + inode = d_inode(parent); + + host_err = fh_want_write(fhp); + if (host_err) + return nfserrno(host_err); + + fh_lock_nested(fhp, I_MUTEX_PARENT); + + child = lookup_one_len(argp->name, parent, argp->len); + if (IS_ERR(child)) { + status = nfserrno(PTR_ERR(child)); + goto out; + } + + if (d_really_is_negative(child)) { + status = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE); + if (status != nfs_ok) + goto out; + } + + status = fh_compose(resfhp, fhp->fh_export, child, fhp); + if (status != nfs_ok) + goto out; + + v_mtime = 0; + v_atime = 0; + if (argp->createmode == NFS3_CREATE_EXCLUSIVE) { + u32 *verifier = (u32 *)argp->verf; + + /* + * Solaris 7 gets confused (bugid 4218508) if these have + * the high bit set, as do xfs filesystems without the + * "bigtime" feature. So just clear the high bits. + */ + v_mtime = verifier[0] & 0x7fffffff; + v_atime = verifier[1] & 0x7fffffff; + } + + if (d_really_is_positive(child)) { + status = nfs_ok; + + switch (argp->createmode) { + case NFS3_CREATE_UNCHECKED: + if (!d_is_reg(child)) + break; + iap->ia_valid &= ATTR_SIZE; + goto set_attr; + case NFS3_CREATE_GUARDED: + status = nfserr_exist; + break; + case NFS3_CREATE_EXCLUSIVE: + if (d_inode(child)->i_mtime.tv_sec == v_mtime && + d_inode(child)->i_atime.tv_sec == v_atime && + d_inode(child)->i_size == 0) { + break; + } + status = nfserr_exist; + } + goto out; + } + + if (!IS_POSIXACL(inode)) + iap->ia_mode &= ~current_umask(); + + host_err = vfs_create(&init_user_ns, inode, child, iap->ia_mode, true); + if (host_err < 0) { + status = nfserrno(host_err); + goto out; + } + + /* A newly created file already has a file size of zero. */ + if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0)) + iap->ia_valid &= ~ATTR_SIZE; + if (argp->createmode == NFS3_CREATE_EXCLUSIVE) { + iap->ia_valid = ATTR_MTIME | ATTR_ATIME | + ATTR_MTIME_SET | ATTR_ATIME_SET; + iap->ia_mtime.tv_sec = v_mtime; + iap->ia_atime.tv_sec = v_atime; + iap->ia_mtime.tv_nsec = 0; + iap->ia_atime.tv_nsec = 0; + } + +set_attr: + status = nfsd_create_setattr(rqstp, fhp, resfhp, iap); + +out: + fh_unlock(fhp); + if (child && !IS_ERR(child)) + dput(child); + fh_drop_write(fhp); + return status; +} + static __be32 nfsd3_proc_create(struct svc_rqst *rqstp) { @@ -239,9 +356,7 @@ nfsd3_proc_create(struct svc_rqst *rqstp) dirfhp = fh_copy(&resp->dirfh, &argp->fh); newfhp = fh_init(&resp->fh, NFS3_FHSIZE); - resp->status = do_nfsd_create(rqstp, dirfhp, argp->name, argp->len, - &argp->attrs, newfhp, argp->createmode, - (u32 *)argp->verf, NULL, NULL); + resp->status = nfsd3_create_file(rqstp, dirfhp, newfhp, argp); return rpc_success; } From patchwork Wed Apr 20 18:29:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820666 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC9FFC433EF for ; Wed, 20 Apr 2022 18:29:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381493AbiDTScA (ORCPT ); Wed, 20 Apr 2022 14:32:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238853AbiDTSb5 (ORCPT ); Wed, 20 Apr 2022 14:31:57 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 546351F60E; Wed, 20 Apr 2022 11:29:10 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 18E2EB8214A; Wed, 20 Apr 2022 18:29:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B26AEC385A1; Wed, 20 Apr 2022 18:29:07 +0000 (UTC) Subject: [PATCH RFC 5/8] NFSD: Refactor NFSv4 OPEN(CREATE) From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:29:06 -0400 Message-ID: <165047934669.1829.387848108212923506.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Copy do_nfsd_create() to nfs4proc.c and remove NFSv3-specific logic. Signed-off-by: Chuck Lever --- fs/nfsd/nfs4proc.c | 162 +++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 152 insertions(+), 10 deletions(-) diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index b207c76a873f..99c0485a29e9 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -37,6 +37,8 @@ #include #include #include +#include + #include #include @@ -235,6 +237,154 @@ static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate &resfh->fh_handle); } +static inline bool nfsd4_create_is_exclusive(int createmode) +{ + return createmode == NFS4_CREATE_EXCLUSIVE || + createmode == NFS4_CREATE_EXCLUSIVE4_1; +} + +/* + * Implement NFSv4's unchecked, guarded, and exclusive create + * semantics for regular files. Open state for this new file is + * subsequently fabricated in nfsd4_process_open2(). + * + * Upon return, caller must release @fhp and @resfhp. + */ +static __be32 +nfsd4_create_file(struct svc_rqst *rqstp, struct svc_fh *fhp, + struct svc_fh *resfhp, struct nfsd4_open *open) +{ + struct iattr *iap = &open->op_iattr; + struct dentry *parent, *child; + __u32 v_mtime, v_atime; + struct inode *inode; + __be32 status; + int host_err; + + if (isdotent(open->op_fname, open->op_fnamelen)) + return nfserr_exist; + if (!(iap->ia_valid & ATTR_MODE)) + iap->ia_mode = 0; + + status = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC); + if (status != nfs_ok) + return status; + parent = fhp->fh_dentry; + inode = d_inode(parent); + + host_err = fh_want_write(fhp); + if (host_err) + return nfserrno(host_err); + + fh_lock_nested(fhp, I_MUTEX_PARENT); + + child = lookup_one_len(open->op_fname, parent, open->op_fnamelen); + if (IS_ERR(child)) { + status = nfserrno(PTR_ERR(child)); + goto out; + } + + if (d_really_is_negative(child)) { + status = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE); + if (status != nfs_ok) + goto out; + } + + status = fh_compose(resfhp, fhp->fh_export, child, fhp); + if (status != nfs_ok) + goto out; + + v_mtime = 0; + v_atime = 0; + if (nfsd4_create_is_exclusive(open->op_createmode)) { + u32 *verifier = (u32 *)open->op_verf.data; + + /* + * Solaris 7 gets confused (bugid 4218508) if these have + * the high bit set, as do xfs filesystems without the + * "bigtime" feature. So just clear the high bits. If this + * is ever changed to use different attrs for storing the + * verifier, then do_open_lookup() will also need to be + * fixed accordingly. + */ + v_mtime = verifier[0] & 0x7fffffff; + v_atime = verifier[1] & 0x7fffffff; + } + + if (d_really_is_positive(child)) { + status = nfs_ok; + + switch (open->op_createmode) { + case NFS4_CREATE_UNCHECKED: + if (!d_is_reg(child)) + break; + + /* + * In NFSv4, we don't want to truncate the file + * now. This would be wrong if the OPEN fails for + * some other reason. Furthermore, if the size is + * nonzero, we should ignore it according to spec! + */ + open->op_truncate = (iap->ia_valid & ATTR_SIZE) && + !iap->ia_size; + break; + case NFS4_CREATE_GUARDED: + status = nfserr_exist; + break; + case NFS4_CREATE_EXCLUSIVE: + if (d_inode(child)->i_mtime.tv_sec == v_mtime && + d_inode(child)->i_atime.tv_sec == v_atime && + d_inode(child)->i_size == 0) { + open->op_created = true; + break; /* subtle */ + } + status = nfserr_exist; + break; + case NFS4_CREATE_EXCLUSIVE4_1: + if (d_inode(child)->i_mtime.tv_sec == v_mtime && + d_inode(child)->i_atime.tv_sec == v_atime && + d_inode(child)->i_size == 0) { + open->op_created = true; + goto set_attr; /* subtle */ + } + status = nfserr_exist; + } + goto out; + } + + if (!IS_POSIXACL(inode)) + iap->ia_mode &= ~current_umask(); + + host_err = vfs_create(&init_user_ns, inode, child, iap->ia_mode, true); + if (host_err < 0) { + status = nfserrno(host_err); + goto out; + } + open->op_created = true; + + /* A newly created file already has a file size of zero. */ + if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0)) + iap->ia_valid &= ~ATTR_SIZE; + if (nfsd4_create_is_exclusive(open->op_createmode)) { + iap->ia_valid = ATTR_MTIME | ATTR_ATIME | + ATTR_MTIME_SET|ATTR_ATIME_SET; + iap->ia_mtime.tv_sec = v_mtime; + iap->ia_atime.tv_sec = v_atime; + iap->ia_mtime.tv_nsec = 0; + iap->ia_atime.tv_nsec = 0; + } + +set_attr: + status = nfsd_create_setattr(rqstp, fhp, resfhp, iap); + +out: + fh_unlock(fhp); + if (child && !IS_ERR(child)) + dput(child); + fh_drop_write(fhp); + return status; +} + static __be32 do_open_lookup(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, struct nfsd4_open *open, struct svc_fh **resfh) { @@ -264,16 +414,8 @@ do_open_lookup(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, stru * yes | yes | GUARDED4 | GUARDED4 */ - /* - * Note: create modes (UNCHECKED,GUARDED...) are the same - * in NFSv4 as in v3 except EXCLUSIVE4_1. - */ current->fs->umask = open->op_umask; - status = do_nfsd_create(rqstp, current_fh, open->op_fname, - open->op_fnamelen, &open->op_iattr, - *resfh, open->op_createmode, - (u32 *)open->op_verf.data, - &open->op_truncate, &open->op_created); + status = nfsd4_create_file(rqstp, current_fh, *resfh, open); current->fs->umask = 0; if (!status && open->op_label.len) @@ -284,7 +426,7 @@ do_open_lookup(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, stru * use the returned bitmask to indicate which attributes * we used to store the verifier: */ - if (nfsd_create_is_exclusive(open->op_createmode) && status == 0) + if (nfsd4_create_is_exclusive(open->op_createmode) && status == 0) open->op_bmval[1] |= (FATTR4_WORD1_TIME_ACCESS | FATTR4_WORD1_TIME_MODIFY); } else From patchwork Wed Apr 20 18:29:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820667 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 736E9C433FE for ; Wed, 20 Apr 2022 18:29:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381507AbiDTScG (ORCPT ); Wed, 20 Apr 2022 14:32:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238853AbiDTScD (ORCPT ); Wed, 20 Apr 2022 14:32:03 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E10441F60E; Wed, 20 Apr 2022 11:29:16 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id A76C5B82142; Wed, 20 Apr 2022 18:29:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 244BCC385A1; Wed, 20 Apr 2022 18:29:14 +0000 (UTC) Subject: [PATCH RFC 6/8] NFSD: Remove do_nfsd_create() From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:29:13 -0400 Message-ID: <165047935304.1829.15228265933411885696.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Now that its two callers have their own version-specific instance of this function, do_nfsd_create() is no longer used. Signed-off-by: Chuck Lever --- fs/nfsd/vfs.c | 150 --------------------------------------------------------- fs/nfsd/vfs.h | 10 ---- 2 files changed, 160 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index ed58f7d46730..407976830a2b 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1393,156 +1393,6 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, rdev, resfhp); } -/* - * NFSv3 and NFSv4 version of nfsd_create - */ -__be32 -do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, - char *fname, int flen, struct iattr *iap, - struct svc_fh *resfhp, int createmode, u32 *verifier, - bool *truncp, bool *created) -{ - struct dentry *dentry, *dchild = NULL; - struct inode *dirp; - __be32 err; - int host_err; - __u32 v_mtime=0, v_atime=0; - - err = nfserr_perm; - if (!flen) - goto out; - err = nfserr_exist; - if (isdotent(fname, flen)) - goto out; - if (!(iap->ia_valid & ATTR_MODE)) - iap->ia_mode = 0; - err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC); - if (err) - goto out; - - dentry = fhp->fh_dentry; - dirp = d_inode(dentry); - - host_err = fh_want_write(fhp); - if (host_err) - goto out_nfserr; - - fh_lock_nested(fhp, I_MUTEX_PARENT); - - /* - * Compose the response file handle. - */ - dchild = lookup_one_len(fname, dentry, flen); - host_err = PTR_ERR(dchild); - if (IS_ERR(dchild)) - goto out_nfserr; - - /* If file doesn't exist, check for permissions to create one */ - if (d_really_is_negative(dchild)) { - err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE); - if (err) - goto out; - } - - err = fh_compose(resfhp, fhp->fh_export, dchild, fhp); - if (err) - goto out; - - if (nfsd_create_is_exclusive(createmode)) { - /* solaris7 gets confused (bugid 4218508) if these have - * the high bit set, as do xfs filesystems without the - * "bigtime" feature. So just clear the high bits. If this is - * ever changed to use different attrs for storing the - * verifier, then do_open_lookup() will also need to be fixed - * accordingly. - */ - v_mtime = verifier[0]&0x7fffffff; - v_atime = verifier[1]&0x7fffffff; - } - - if (d_really_is_positive(dchild)) { - err = 0; - - switch (createmode) { - case NFS3_CREATE_UNCHECKED: - if (! d_is_reg(dchild)) - goto out; - else if (truncp) { - /* in nfsv4, we need to treat this case a little - * differently. we don't want to truncate the - * file now; this would be wrong if the OPEN - * fails for some other reason. furthermore, - * if the size is nonzero, we should ignore it - * according to spec! - */ - *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size; - } - else { - iap->ia_valid &= ATTR_SIZE; - goto set_attr; - } - break; - case NFS3_CREATE_EXCLUSIVE: - if ( d_inode(dchild)->i_mtime.tv_sec == v_mtime - && d_inode(dchild)->i_atime.tv_sec == v_atime - && d_inode(dchild)->i_size == 0 ) { - if (created) - *created = true; - break; - } - fallthrough; - case NFS4_CREATE_EXCLUSIVE4_1: - if ( d_inode(dchild)->i_mtime.tv_sec == v_mtime - && d_inode(dchild)->i_atime.tv_sec == v_atime - && d_inode(dchild)->i_size == 0 ) { - if (created) - *created = true; - goto set_attr; - } - fallthrough; - case NFS3_CREATE_GUARDED: - err = nfserr_exist; - } - goto out; - } - - if (!IS_POSIXACL(dirp)) - iap->ia_mode &= ~current_umask(); - - host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true); - if (host_err < 0) - goto out_nfserr; - if (created) - *created = true; - - nfsd_check_ignore_resizing(iap); - - if (nfsd_create_is_exclusive(createmode)) { - /* Cram the verifier into atime/mtime */ - iap->ia_valid = ATTR_MTIME|ATTR_ATIME - | ATTR_MTIME_SET|ATTR_ATIME_SET; - /* XXX someone who knows this better please fix it for nsec */ - iap->ia_mtime.tv_sec = v_mtime; - iap->ia_atime.tv_sec = v_atime; - iap->ia_mtime.tv_nsec = 0; - iap->ia_atime.tv_nsec = 0; - } - - set_attr: - err = nfsd_create_setattr(rqstp, fhp, resfhp, iap); - - out: - fh_unlock(fhp); - if (dchild && !IS_ERR(dchild)) - dput(dchild); - fh_drop_write(fhp); - return err; - - out_nfserr: - err = nfserrno(host_err); - goto out; -} - /* * Read a symlink. On entry, *lenp must contain the maximum path length that * fits into the buffer. On return, it contains the true length. diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h index 1f32a83456b0..f99794b033a5 100644 --- a/fs/nfsd/vfs.h +++ b/fs/nfsd/vfs.h @@ -71,10 +71,6 @@ __be32 nfsd_create(struct svc_rqst *, struct svc_fh *, __be32 nfsd_access(struct svc_rqst *, struct svc_fh *, u32 *, u32 *); __be32 nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct svc_fh *resfhp, struct iattr *iap); -__be32 do_nfsd_create(struct svc_rqst *, struct svc_fh *, - char *name, int len, struct iattr *attrs, - struct svc_fh *res, int createmode, - u32 *verifier, bool *truncp, bool *created); __be32 nfsd_commit(struct svc_rqst *rqst, struct svc_fh *fhp, u64 offset, u32 count, __be32 *verf); #ifdef CONFIG_NFSD_V4 @@ -161,10 +157,4 @@ static inline __be32 fh_getattr(const struct svc_fh *fh, struct kstat *stat) AT_STATX_SYNC_AS_STAT)); } -static inline int nfsd_create_is_exclusive(int createmode) -{ - return createmode == NFS3_CREATE_EXCLUSIVE - || createmode == NFS4_CREATE_EXCLUSIVE4_1; -} - #endif /* LINUX_NFSD_VFS_H */ From patchwork Wed Apr 20 18:29:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820668 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE835C433FE for ; Wed, 20 Apr 2022 18:29:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381490AbiDTScO (ORCPT ); Wed, 20 Apr 2022 14:32:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53050 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1381512AbiDTScI (ORCPT ); Wed, 20 Apr 2022 14:32:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ABD1238BFF; Wed, 20 Apr 2022 11:29:21 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4746B61B1F; Wed, 20 Apr 2022 18:29:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B495C385A0; Wed, 20 Apr 2022 18:29:20 +0000 (UTC) Subject: [PATCH RFC 7/8] NFSD: Clean up nfsd_open_verified() From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:29:19 -0400 Message-ID: <165047935951.1829.4140838884832238133.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Its only caller always passes S_IFREG as the @type parameter. As an additional clean-up, add a kerneldoc comment. Signed-off-by: Chuck Lever --- fs/nfsd/filecache.c | 4 ++-- fs/nfsd/vfs.c | 15 ++++++++++++--- fs/nfsd/vfs.h | 2 +- 3 files changed, 15 insertions(+), 6 deletions(-) diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 2c1b027774d4..781bef7e42d9 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -995,8 +995,8 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, nf->nf_mark = nfsd_file_mark_find_or_create(nf); if (nf->nf_mark) - status = nfsd_open_verified(rqstp, fhp, S_IFREG, - may_flags, &nf->nf_file); + status = nfsd_open_verified(rqstp, fhp, may_flags, + &nf->nf_file); else status = nfserr_jukebox; /* diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 407976830a2b..893b5f21dab9 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -827,14 +827,23 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, return err; } +/** + * nfsd_open_verified - Open a regular file for the filecache + * @rqstp: RPC request + * @fhp: NFS filehandle of the file to open + * @may_flags: internal permission flags + * @filp: OUT: open "struct file *" + * + * Returns an nfsstat value in network byte order. + */ __be32 -nfsd_open_verified(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, - int may_flags, struct file **filp) +nfsd_open_verified(struct svc_rqst *rqstp, struct svc_fh *fhp, int may_flags, + struct file **filp) { __be32 err; validate_process_creds(); - err = __nfsd_open(rqstp, fhp, type, may_flags, filp); + err = __nfsd_open(rqstp, fhp, S_IFREG, may_flags, filp); validate_process_creds(); return err; } diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h index f99794b033a5..26347d76f44a 100644 --- a/fs/nfsd/vfs.h +++ b/fs/nfsd/vfs.h @@ -86,7 +86,7 @@ __be32 nfsd_setxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, int nfsd_open_break_lease(struct inode *, int); __be32 nfsd_open(struct svc_rqst *, struct svc_fh *, umode_t, int, struct file **); -__be32 nfsd_open_verified(struct svc_rqst *, struct svc_fh *, umode_t, +__be32 nfsd_open_verified(struct svc_rqst *, struct svc_fh *, int, struct file **); __be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, loff_t offset, From patchwork Wed Apr 20 18:29:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 12820669 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65A47C433F5 for ; Wed, 20 Apr 2022 18:29:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381516AbiDTScU (ORCPT ); Wed, 20 Apr 2022 14:32:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53084 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1381509AbiDTScP (ORCPT ); Wed, 20 Apr 2022 14:32:15 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1284723BDE; Wed, 20 Apr 2022 11:29:28 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 92DB361B1F; Wed, 20 Apr 2022 18:29:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9574C385A8; Wed, 20 Apr 2022 18:29:26 +0000 (UTC) Subject: [PATCH RFC 8/8] NFSD: Instantiate a struct file when creating a regular NFSv4 file From: Chuck Lever To: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 20 Apr 2022 14:29:25 -0400 Message-ID: <165047936589.1829.37677464497968942.stgit@manet.1015granger.net> In-Reply-To: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> References: <165047903719.1829.18357114060053600197.stgit@manet.1015granger.net> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org There have been reports of races that cause NFSv4 OPEN(CREATE) to return an error even though the requested file was created. NFSv4 does not provide a status code for this case. To mitigate some of these problems, reorganize the NFSv4 OPEN(CREATE) logic to allocate resources before the file is actually created, and open the new file while the parent directory is still locked. Two new APIs are added: + Add an API that works like nfsd_file_acquire() but does not open the underlying file. The OPEN(CREATE) path can use this API when it already has an open file. + Add an API that is kin to dentry_open(). NFSD needs to create a file and grab an open "struct file *" atomically. The alloc_empty_file() has to be done before the inode create. If it fails (for example, because the NFS server has exceeded its max_files limit), we avoid creating the file and can still return an error to the NFS client. BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=382 Signed-off-by: Chuck Lever --- fs/nfsd/filecache.c | 51 ++++++++++++++++++++++++++++++++++++++++++++------- fs/nfsd/filecache.h | 2 ++ fs/nfsd/nfs4proc.c | 43 +++++++++++++++++++++++++++++++++++++++---- fs/nfsd/nfs4state.c | 16 +++++++++++++--- fs/nfsd/xdr4.h | 1 + fs/open.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 2 ++ 7 files changed, 145 insertions(+), 14 deletions(-) diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 781bef7e42d9..24772f246461 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -897,9 +897,9 @@ nfsd_file_is_cached(struct inode *inode) return ret; } -__be32 -nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, - unsigned int may_flags, struct nfsd_file **pnf) +static __be32 +nfsd_do_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, + unsigned int may_flags, struct nfsd_file **pnf, bool open) { __be32 status; struct net *net = SVC_NET(rqstp); @@ -994,10 +994,13 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, nfsd_file_gc(); nf->nf_mark = nfsd_file_mark_find_or_create(nf); - if (nf->nf_mark) - status = nfsd_open_verified(rqstp, fhp, may_flags, - &nf->nf_file); - else + if (nf->nf_mark) { + if (open) + status = nfsd_open_verified(rqstp, fhp, may_flags, + &nf->nf_file); + else + status = nfs_ok; + } else status = nfserr_jukebox; /* * If construction failed, or we raced with a call to unlink() @@ -1017,6 +1020,40 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, goto out; } +/** + * nfsd_file_acquire - Get a struct nfsd_file with an open file + * @rqstp: the RPC transaction being executed + * @fhp: the NFS filehandle of the file to be opened + * @may_flags: NFSD_MAY_ settings for the file + * @pnf: OUT: new or found "struct nfsd_file" object + * + * Returns nfs_ok and sets @pnf on success; otherwise an nfsstat in + * network byte order is returned. + */ +__be32 +nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, + unsigned int may_flags, struct nfsd_file **pnf) +{ + return nfsd_do_file_acquire(rqstp, fhp, may_flags, pnf, true); +} + +/** + * nfsd_file_create - Get a struct nfsd_file, do not open + * @rqstp: the RPC transaction being executed + * @fhp: the NFS filehandle of the file just created + * @may_flags: NFSD_MAY_ settings for the file + * @pnf: OUT: new or found "struct nfsd_file" object + * + * Returns nfs_ok and sets @pnf on success; otherwise an nfsstat in + * network byte order is returned. + */ +__be32 +nfsd_file_create(struct svc_rqst *rqstp, struct svc_fh *fhp, + unsigned int may_flags, struct nfsd_file **pnf) +{ + return nfsd_do_file_acquire(rqstp, fhp, may_flags, pnf, false); +} + /* * Note that fields may be added, removed or reordered in the future. Programs * scraping this file for info should test the labels to ensure they're diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h index 435ceab27897..1da0c79a5580 100644 --- a/fs/nfsd/filecache.h +++ b/fs/nfsd/filecache.h @@ -59,5 +59,7 @@ void nfsd_file_close_inode_sync(struct inode *inode); bool nfsd_file_is_cached(struct inode *inode); __be32 nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int may_flags, struct nfsd_file **nfp); +__be32 nfsd_file_create(struct svc_rqst *rqstp, struct svc_fh *fhp, + unsigned int may_flags, struct nfsd_file **nfp); int nfsd_file_cache_stats_open(struct inode *, struct file *); #endif /* _FS_NFSD_FILECACHE_H */ diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 99c0485a29e9..28bae84d7809 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -243,6 +243,37 @@ static inline bool nfsd4_create_is_exclusive(int createmode) createmode == NFS4_CREATE_EXCLUSIVE4_1; } +static __be32 +nfsd4_vfs_create(struct svc_fh *fhp, struct dentry *child, + struct nfsd4_open *open) +{ + struct file *filp; + struct path path; + int oflags; + + oflags = O_CREAT | O_LARGEFILE; + switch (open->op_share_access & NFS4_SHARE_ACCESS_BOTH) { + case NFS4_SHARE_ACCESS_WRITE: + oflags |= O_WRONLY; + break; + case NFS4_SHARE_ACCESS_BOTH: + oflags |= O_RDWR; + break; + default: + oflags |= O_RDONLY; + } + + path.mnt = fhp->fh_export->ex_path.mnt; + path.dentry = child; + filp = dentry_create(&path, oflags, open->op_iattr.ia_mode, + current_cred()); + if (IS_ERR(filp)) + return nfserrno(PTR_ERR(filp)); + + open->op_filp = filp; + return nfs_ok; +} + /* * Implement NFSv4's unchecked, guarded, and exclusive create * semantics for regular files. Open state for this new file is @@ -355,11 +386,9 @@ nfsd4_create_file(struct svc_rqst *rqstp, struct svc_fh *fhp, if (!IS_POSIXACL(inode)) iap->ia_mode &= ~current_umask(); - host_err = vfs_create(&init_user_ns, inode, child, iap->ia_mode, true); - if (host_err < 0) { - status = nfserrno(host_err); + status = nfsd4_vfs_create(fhp, child, open); + if (status != nfs_ok) goto out; - } open->op_created = true; /* A newly created file already has a file size of zero. */ @@ -517,6 +546,8 @@ nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, (int)open->op_fnamelen, open->op_fname, open->op_openowner); + open->op_filp = NULL; + /* This check required by spec. */ if (open->op_create && open->op_claim_type != NFS4_OPEN_CLAIM_NULL) return nfserr_inval; @@ -613,6 +644,10 @@ nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, if (reclaim && !status) nn->somebody_reclaimed = true; out: + if (open->op_filp) { + fput(open->op_filp); + open->op_filp = NULL; + } if (resfh && resfh != &cstate->current_fh) { fh_dup2(&cstate->current_fh, resfh); fh_put(resfh); diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 234e852fcdfa..e7c28ddf2538 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4985,9 +4985,19 @@ static __be32 nfs4_get_vfs_file(struct svc_rqst *rqstp, struct nfs4_file *fp, if (!fp->fi_fds[oflag]) { spin_unlock(&fp->fi_lock); - status = nfsd_file_acquire(rqstp, cur_fh, access, &nf); - if (status) - goto out_put_access; + + if (!open->op_filp) { + status = nfsd_file_acquire(rqstp, cur_fh, access, &nf); + if (status != nfs_ok) + goto out_put_access; + } else { + status = nfsd_file_create(rqstp, cur_fh, access, &nf); + if (status != nfs_ok) + goto out_put_access; + nf->nf_file = open->op_filp; + open->op_filp = NULL; + } + spin_lock(&fp->fi_lock); if (!fp->fi_fds[oflag]) { fp->fi_fds[oflag] = nf; diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h index 846ab6df9d48..7b744011f2d3 100644 --- a/fs/nfsd/xdr4.h +++ b/fs/nfsd/xdr4.h @@ -273,6 +273,7 @@ struct nfsd4_open { bool op_truncate; /* used during processing */ bool op_created; /* used during processing */ struct nfs4_openowner *op_openowner; /* used during processing */ + struct file *op_filp; /* used during processing */ struct nfs4_file *op_file; /* used during processing */ struct nfs4_ol_stateid *op_stp; /* used during processing */ struct nfs4_clnt_odstate *op_odstate; /* used during processing */ diff --git a/fs/open.c b/fs/open.c index 1315253e0247..e3cf72c269e1 100644 --- a/fs/open.c +++ b/fs/open.c @@ -981,6 +981,50 @@ struct file *dentry_open(const struct path *path, int flags, } EXPORT_SYMBOL(dentry_open); +/** + * dentry_create - Create and open a file + * @path: path to create + * @flags: O_ flags + * @mode: mode bits for new file + * @cred: credentials to use + * + * Caller must hold the parent directory's lock, and have prepared + * a negative dentry, placed in @path->dentry, for the new file. + * + * On success, returns a "struct file *". Otherwise a ERR_PTR + * is returned. + */ +struct file *dentry_create(const struct path *path, int flags, umode_t mode, + const struct cred *cred) +{ + struct dentry *parent; + struct file *f; + int error; + + validate_creds(cred); + f = alloc_empty_file(flags, cred); + if (IS_ERR(f)) + return f; + + parent = dget_parent(path->dentry); + error = vfs_create(mnt_user_ns(path->mnt), d_inode(parent), + path->dentry, mode, true); + dput(parent); + if (error) { + fput(f); + return ERR_PTR(error); + } + + error = vfs_open(path, f); + if (error) { + fput(f); + return ERR_PTR(error); + } + + return f; +} +EXPORT_SYMBOL(dentry_create); + struct file *open_with_fake_path(const struct path *path, int flags, struct inode *inode, const struct cred *cred) { diff --git a/include/linux/fs.h b/include/linux/fs.h index bbde95387a23..53501d710441 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2630,6 +2630,8 @@ static inline struct file *file_open_root_mnt(struct vfsmount *mnt, name, flags, mode); } extern struct file * dentry_open(const struct path *, int, const struct cred *); +extern struct file *dentry_create(const struct path *path, int flags, + umode_t mode, const struct cred *cred); extern struct file * open_with_fake_path(const struct path *, int, struct inode*, const struct cred *); static inline struct file *file_clone_open(struct file *file)