From patchwork Tue Apr 9 19:42:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 10892197 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5E48913B5 for ; Tue, 9 Apr 2019 19:42:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4CA2B28950 for ; Tue, 9 Apr 2019 19:42:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4B0D828991; Tue, 9 Apr 2019 19:42:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BA0A828987 for ; Tue, 9 Apr 2019 19:42:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726656AbfDITmf (ORCPT ); Tue, 9 Apr 2019 15:42:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:57790 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726615AbfDITme (ORCPT ); Tue, 9 Apr 2019 15:42:34 -0400 Received: from tleilax.poochiereds.net (cpe-71-70-156-158.nc.res.rr.com [71.70.156.158]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 091C42084F for ; Tue, 9 Apr 2019 19:42:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554838954; bh=wR1kEJ7C2PXPK9sQz61e86HHBKLNOacLjXJIK6Y/KDc=; h=From:To:Subject:Date:In-Reply-To:References:From; b=bGXJHQO7CTIvEaBFVGI6LSXx8lQNJH1Luzhw7MtcSNIyHMOsNSXgxK2OvkXFlyS5b Ij5cLN/fQB5nSmvTzb0gV8BNQJ3RKkIddtqby4WhAvNJVJ7CCRMk8yGPUu/e2dC6V0 YthnT5wT6W9dLZWJAAQ74pPp3LQqcEADUaX0oM38= From: Jeff Layton To: ceph-devel@vger.kernel.org Subject: [RFC PATCH 06/11] ceph: simplify arguments and return semantics of try_get_cap_refs Date: Tue, 9 Apr 2019 15:42:24 -0400 Message-Id: <20190409194229.8247-7-jlayton@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190409194229.8247-1-jlayton@kernel.org> References: <20190409194229.8247-1-jlayton@kernel.org> MIME-Version: 1.0 Sender: ceph-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The return of this function is rather complex. It can return 0 or 1, and in the case of a 1 return, the "err" pointer will be filled out. This necessitates a lot of copying of values. We can achieve the same effect by just returning 0, 1 or a negative error code, and drop the "err" argument from this function. Signed-off-by: Jeff Layton --- fs/ceph/caps.c | 76 ++++++++++++++++++++------------------------------ 1 file changed, 30 insertions(+), 46 deletions(-) diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 90090a56899e..9e0b464d374f 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2525,9 +2525,14 @@ static void __take_cap_refs(struct ceph_inode_info *ci, int got, * to (when applicable), and check against max_size here as well. * Note that caller is responsible for ensuring max_size increases are * requested from the MDS. + * + * Returns 0 if caps were not able to be acquired (yet), a 1 if they were, + * or a negative error code. + * + * FIXME: how does a 0 return differ from -EAGAIN? */ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, - loff_t endoff, bool nonblock, int *got, int *err) + loff_t endoff, bool nonblock, int *got) { struct inode *inode = &ci->vfs_inode; struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; @@ -2547,8 +2552,7 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, if ((file_wanted & need) != need) { dout("try_get_cap_refs need %s file_wanted %s, EBADF\n", ceph_cap_string(need), ceph_cap_string(file_wanted)); - *err = -EBADF; - ret = 1; + ret = -EBADF; goto out_unlock; } @@ -2569,10 +2573,8 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) { dout("get_cap_refs %p endoff %llu > maxsize %llu\n", inode, endoff, ci->i_max_size); - if (endoff > ci->i_requested_max_size) { - *err = -EAGAIN; - ret = 1; - } + if (endoff > ci->i_requested_max_size) + ret = -EAGAIN; goto out_unlock; } /* @@ -2607,8 +2609,7 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, * task isn't in TASK_RUNNING state */ if (nonblock) { - *err = -EAGAIN; - ret = 1; + ret = -EAGAIN; goto out_unlock; } @@ -2637,8 +2638,7 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, if (session_readonly) { dout("get_cap_refs %p needed %s but mds%d readonly\n", inode, ceph_cap_string(need), ci->i_auth_cap->mds); - *err = -EROFS; - ret = 1; + ret = -EROFS; goto out_unlock; } @@ -2647,16 +2647,14 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) { dout("get_cap_refs %p forced umount\n", inode); - *err = -EIO; - ret = 1; + ret = -EIO; goto out_unlock; } mds_wanted = __ceph_caps_mds_wanted(ci, false); if (need & ~(mds_wanted & need)) { dout("get_cap_refs %p caps were dropped" " (session killed?)\n", inode); - *err = -ESTALE; - ret = 1; + ret = -ESTALE; goto out_unlock; } if (!(file_wanted & ~mds_wanted)) @@ -2707,7 +2705,7 @@ static void check_max_size(struct inode *inode, loff_t endoff) int ceph_try_get_caps(struct ceph_inode_info *ci, int need, int want, bool nonblock, int *got) { - int ret, err = 0; + int ret; BUG_ON(need & ~CEPH_CAP_FILE_RD); BUG_ON(want & ~(CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO|CEPH_CAP_FILE_SHARED)); @@ -2715,15 +2713,8 @@ int ceph_try_get_caps(struct ceph_inode_info *ci, int need, int want, if (ret < 0) return ret; - ret = try_get_cap_refs(ci, need, want, 0, nonblock, got, &err); - if (ret) { - if (err == -EAGAIN) { - ret = 0; - } else if (err < 0) { - ret = err; - } - } - return ret; + ret = try_get_cap_refs(ci, need, want, 0, nonblock, got); + return ret == -EAGAIN ? 0 : ret; } /* @@ -2734,7 +2725,7 @@ int ceph_try_get_caps(struct ceph_inode_info *ci, int need, int want, int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, loff_t endoff, int *got, struct page **pinned_page) { - int _got, ret, err = 0; + int _got, ret; ret = ceph_pool_perm_check(ci, need); if (ret < 0) @@ -2744,21 +2735,19 @@ int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, if (endoff > 0) check_max_size(&ci->vfs_inode, endoff); - err = 0; _got = 0; ret = try_get_cap_refs(ci, need, want, endoff, - false, &_got, &err); - if (ret) { - if (err == -EAGAIN) - continue; - if (err < 0) - ret = err; - } else { + false, &_got); + if (ret == -EAGAIN) { + continue; + } else if (!ret) { + int err; + DEFINE_WAIT_FUNC(wait, woken_wake_function); add_wait_queue(&ci->i_cap_wq, &wait); - while (!try_get_cap_refs(ci, need, want, endoff, - true, &_got, &err)) { + while (!(err = try_get_cap_refs(ci, need, want, endoff, + true, &_got))) { if (signal_pending(current)) { ret = -ERESTARTSYS; break; @@ -2767,19 +2756,14 @@ int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, } remove_wait_queue(&ci->i_cap_wq, &wait); - if (err == -EAGAIN) continue; - if (err < 0) - ret = err; } - if (ret < 0) { - if (err == -ESTALE) { - /* session was killed, try renew caps */ - ret = ceph_renew_caps(&ci->vfs_inode); - if (ret == 0) - continue; - } + if (ret == -ESTALE) { + /* session was killed, try renew caps */ + ret = ceph_renew_caps(&ci->vfs_inode); + if (ret == 0) + continue; return ret; }