From patchwork Mon Aug 17 22:04:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11719459 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E1C25618 for ; Mon, 17 Aug 2020 22:12:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD2002072E for ; Mon, 17 Aug 2020 22:12:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730254AbgHQWMF (ORCPT ); Mon, 17 Aug 2020 18:12:05 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:33606 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730257AbgHQWLv (ORCPT ); Mon, 17 Aug 2020 18:11:51 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1k7nM5-001H8C-Vy; Mon, 17 Aug 2020 16:11:50 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.int.ebiederm.org) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.87) (envelope-from ) id 1k7nKm-0004PB-L7; Mon, 17 Aug 2020 16:10:29 -0600 From: "Eric W. Biederman" To: linux-kernel@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, criu@openvz.org, bpf@vger.kernel.org, Linus Torvalds , Alexander Viro , Christian Brauner , Oleg Nesterov , Cyrill Gorcunov , Jann Horn , Kees Cook , =?utf-8?q?Da?= =?utf-8?q?niel_P=2E_Berrang=C3=A9?= , Jeff Layton , Miklos Szeredi , Matthew Wilcox , "J. Bruce Fields" , Matthew Wilcox , Trond Myklebust , Chris Wright , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , Andrii Nakryiko , John Fastabend , KP Singh , "Eric W. Biederman" Date: Mon, 17 Aug 2020 17:04:22 -0500 Message-Id: <20200817220425.9389-14-ebiederm@xmission.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <87ft8l6ic3.fsf@x220.int.ebiederm.org> References: <87ft8l6ic3.fsf@x220.int.ebiederm.org> MIME-Version: 1.0 X-XM-SPF: eid=1k7nKm-0004PB-L7;;;mid=<20200817220425.9389-14-ebiederm@xmission.com>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+/b1FqIJGp7GfPLwyPwndSgsGRDfb1vTc= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa04.xmission.com X-Spam-Level: * X-Spam-Status: No, score=1.3 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TooManySym_01,XMNoVowels autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 1.5 XMNoVowels Alpha-numberic number with no vowels * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa04 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa04 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: *;linux-kernel@vger.kernel.org X-Spam-Relay-Country: X-Spam-Timing: total 400 ms - load_scoreonly_sql: 0.06 (0.0%), signal_user_changed: 10 (2.4%), b_tie_ro: 8 (2.0%), parse: 1.04 (0.3%), extract_message_metadata: 10 (2.5%), get_uri_detail_list: 1.79 (0.4%), tests_pri_-1000: 13 (3.2%), tests_pri_-950: 1.03 (0.3%), tests_pri_-900: 0.84 (0.2%), tests_pri_-90: 88 (22.0%), check_bayes: 87 (21.8%), b_tokenize: 9 (2.3%), b_tok_get_all: 9 (2.2%), b_comp_prob: 2.4 (0.6%), b_tok_touch_all: 64 (15.9%), b_finish: 0.69 (0.2%), tests_pri_0: 263 (65.7%), check_dkim_signature: 0.51 (0.1%), check_dkim_adsp: 1.99 (0.5%), poll_dns_idle: 0.52 (0.1%), tests_pri_10: 2.3 (0.6%), tests_pri_500: 9 (2.2%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH 14/17] file: Merge __fd_install into fd_install X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org The function __fd_install was added to support binder[1]. With binder fixed[2] there are no more users. Further with get_files_struct removed there can be no more users of __fd_install that pass anything except current->files. As fd_install just calls __fd_install with "files=current->files", merge them together by transforming the files parameter into a local variable initialized to current->files. [1] f869e8a7f753 ("expose a low-level variant of fd_install() for binder") [2] 44d8047f1d87 ("binder: use standard functions to allocate fds") Signed-off-by: "Eric W. Biederman" Acked-by: Christian Brauner --- fs/file.c | 25 ++++++------------------- include/linux/fdtable.h | 2 -- 2 files changed, 6 insertions(+), 21 deletions(-) diff --git a/fs/file.c b/fs/file.c index 605e756f3c63..1a755811669d 100644 --- a/fs/file.c +++ b/fs/file.c @@ -157,7 +157,7 @@ static int expand_fdtable(struct files_struct *files, unsigned int nr) spin_unlock(&files->file_lock); new_fdt = alloc_fdtable(nr); - /* make sure all __fd_install() have seen resize_in_progress + /* make sure all fd_install() have seen resize_in_progress * or have finished their rcu_read_lock_sched() section. */ if (atomic_read(&files->count) > 1) @@ -180,7 +180,7 @@ static int expand_fdtable(struct files_struct *files, unsigned int nr) rcu_assign_pointer(files->fdt, new_fdt); if (cur_fdt != &files->fdtab) call_rcu(&cur_fdt->rcu, free_fdtable_rcu); - /* coupled with smp_rmb() in __fd_install() */ + /* coupled with smp_rmb() in fd_install() */ smp_wmb(); return 1; } @@ -569,17 +569,13 @@ EXPORT_SYMBOL(put_unused_fd); * It should never happen - if we allow dup2() do it, _really_ bad things * will follow. * - * NOTE: __fd_install() variant is really, really low-level; don't - * use it unless you are forced to by truly lousy API shoved down - * your throat. 'files' *MUST* be either current->files or obtained - * by get_files_struct(current) done by whoever had given it to you, - * or really bad things will happen. Normally you want to use - * fd_install() instead. + * This consumes the "file" refcount, so callers should treat it + * as if they had called fput(file). */ -void __fd_install(struct files_struct *files, unsigned int fd, - struct file *file) +void fd_install(unsigned int fd, struct file *file) { + struct files_struct *files = current->files; struct fdtable *fdt; rcu_read_lock_sched(); @@ -601,15 +597,6 @@ void __fd_install(struct files_struct *files, unsigned int fd, rcu_read_unlock_sched(); } -/* - * This consumes the "file" refcount, so callers should treat it - * as if they had called fput(file). - */ -void fd_install(unsigned int fd, struct file *file) -{ - __fd_install(current->files, fd, file); -} - EXPORT_SYMBOL(fd_install); static struct file *pick_file(struct files_struct *files, unsigned fd) diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index 8c4bc6aa19c9..4da8aacc461a 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -118,8 +118,6 @@ int iterate_fd(struct files_struct *, unsigned, extern int __alloc_fd(struct files_struct *files, unsigned start, unsigned end, unsigned flags); -extern void __fd_install(struct files_struct *files, - unsigned int fd, struct file *file); extern int __close_fd(struct files_struct *files, unsigned int fd); extern int __close_range(unsigned int fd, unsigned int max_fd, unsigned int flags);