Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932415AbbEKSLH (ORCPT ); Mon, 11 May 2015 14:11:07 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:47623 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755071AbbEKSIb (ORCPT ); Mon, 11 May 2015 14:08:31 -0400 From: Al Viro To: Linus Torvalds Cc: Neil Brown , Christoph Hellwig , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v3 106/110] namei: don't unlazy until get_link() Date: Mon, 11 May 2015 19:08:06 +0100 Message-Id: <1431367690-5223-106-git-send-email-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <20150511180650.GA4147@ZenIV.linux.org.uk> References: <20150511180650.GA4147@ZenIV.linux.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2115 Lines: 83 From: Al Viro Signed-off-by: Al Viro --- fs/namei.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 090214b..4d6065d 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -536,10 +536,19 @@ static void restore_nameidata(struct nameidata *old) static int __nd_alloc_stack(struct nameidata *nd) { - struct saved *p = kmalloc(MAXSYMLINKS * sizeof(struct saved), + struct saved *p; + + if (nd->flags & LOOKUP_RCU) { + p= kmalloc(MAXSYMLINKS * sizeof(struct saved), + GFP_ATOMIC); + if (unlikely(!p)) + return -ECHILD; + } else { + p= kmalloc(MAXSYMLINKS * sizeof(struct saved), GFP_KERNEL); - if (unlikely(!p)) - return -ENOMEM; + if (unlikely(!p)) + return -ENOMEM; + } memcpy(p, nd->internal, sizeof(nd->internal)); nd->stack = p; return 0; @@ -949,8 +958,10 @@ const char *get_link(struct nameidata *nd) int error; const char *res; - BUG_ON(nd->flags & LOOKUP_RCU); - + if (nd->flags & LOOKUP_RCU) { + if (unlikely(unlazy_walk(nd, NULL, 0))) + return ERR_PTR(-ECHILD); + } cond_resched(); touch_atime(&last->link); @@ -1632,17 +1643,21 @@ static int pick_link(struct nameidata *nd, struct path *link, path_to_nameidata(link, nd); return -ELOOP; } - if (nd->flags & LOOKUP_RCU) { - if (unlikely(unlazy_link(nd, link, seq))) - return -ECHILD; - } else { + if (!(nd->flags & LOOKUP_RCU)) { if (link->mnt == nd->path.mnt) mntget(link->mnt); } error = nd_alloc_stack(nd); if (unlikely(error)) { - path_put(link); - return error; + if (error == -ECHILD) { + if (unlikely(unlazy_link(nd, link, seq))) + return -ECHILD; + error = nd_alloc_stack(nd); + } + if (error) { + path_put(link); + return error; + } } last = nd->stack + nd->depth++; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/