From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fhigh-a5-smtp.messagingengine.com (fhigh-a5-smtp.messagingengine.com [103.168.172.156]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7852E35CB95; Mon, 27 Apr 2026 03:37:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=103.168.172.156 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777261028; cv=none; b=hvbx0K2ecc1uZUlCyDUInXLVoPHKemBCNzq7sZewCOUqk0ljfom0k3rDlfu9Uxnz0VW6J9kjvviaJyrOyN614Xu3O8ehSw9umTln/S7FsJ0r+H+lcAoZaGkGKuoorek+5nt5/KxIDRQgd5svKE7Ohbh54TYKwT3zPoathjyH11w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777261028; c=relaxed/simple; bh=Af17cpjWLrgjln+x15PYEXYO/pHIZybmrmOg/uu6FGs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BMA+UJz7u+YhdTonQf96Yk72uVLnBLnh0SZNNg3QBYmStLHnEv/O0GqrhOinYy7kQWYzRuJDT1l33P9BaApavx4sDlTWv/2he55JOM4reu3EnqXF7wfTz3tqwKR2r0p7EMIayfPub8RQgDp22xMHifUJupEqCxxoD6TMAZ9Owtc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ownmail.net; spf=pass smtp.mailfrom=ownmail.net; dkim=pass (2048-bit key) header.d=ownmail.net header.i=@ownmail.net header.b=IgVFNUI+; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=WVACiltR; arc=none smtp.client-ip=103.168.172.156 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ownmail.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ownmail.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ownmail.net header.i=@ownmail.net header.b="IgVFNUI+"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="WVACiltR" Received: from phl-compute-01.internal (phl-compute-01.internal [10.202.2.41]) by mailfhigh.phl.internal (Postfix) with ESMTP id CC47714000BD; Sun, 26 Apr 2026 23:37:06 -0400 (EDT) Received: from phl-frontend-03 ([10.202.2.162]) by phl-compute-01.internal (MEProxy); Sun, 26 Apr 2026 23:37:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ownmail.net; h= cc:cc:content-transfer-encoding:content-type:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:reply-to:subject:subject:to:to; s=fm2; t=1777261026; x=1777347426; bh=2Sazp1M0TdInI6mi6hF1QSnGjDghjOgL8lkwZNivMpc=; b= IgVFNUI+/gOyDFNPlGJ2o+BShsyOgjot50UzS4rGGq9IW/0ZUlvJ0MLNzBTcvuVg WVb3iFHJw4nOOjuInIaSxSicohVL9DKhagmu0ol55wHzap/fnuLhbPIG856cptnf CpyhUkeUPKX5qW5DQKMvmwWoFxaNZt0coHX8I14qGnbRB2QO55MpDvnO+0dZx6Pz feq5kWPtMa81ACUu8nN81D+DRSwOStqPzBR8iTM0yjRHTAl2npqQ0klqyy9rpyO4 /wwvOc7pAeR+ZbT8vzpED23SsYDSo93KhImvaywVSKYusRQsSgm4gZxGMQSxfJ1C byXVv86d4IOEIEwGE2lIUQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:date:date:feedback-id:feedback-id:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:reply-to:subject:subject:to:to:x-me-proxy:x-me-sender :x-me-sender:x-sasl-enc; s=fm2; t=1777261026; x=1777347426; bh=2 Sazp1M0TdInI6mi6hF1QSnGjDghjOgL8lkwZNivMpc=; b=WVACiltRQdApAwYHI ZqnR3UkX3wiXEfov35t9yGEUOOxOKCUnXcDhCB55/7/p8njZuTEeP5HGKzjognGh 8sUNeNPL0w1gulJgmMOLd8b5jY8Rxx6LOrXiZJghkWQyaig2Kz5q74jtUvvW9cF4 zYhLp0HiYAyGzkcouQiAvNF3R5wetmRaG7YBa3eXwu+tV7B6b5NB+Ncvs89vc/kr r23vQNE9SweRKSCSZLSLUoemxnbX4javb8c8Do+WSk+gAZ4+YgvMfuUKQ3humkDo o+NYCKr/FAzo/MHd9KCdZnxPIW96l7DfhwNPXWa8S2NurZMHaOlXOSf+GocEFrF7 nzZqg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeefhedrtddtgdejjeeivdcutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpuffrtefokffrpgfnqfghnecuuegr ihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjug hrpefhvfevufffkffojghfrhgggfestdekredtredttdenucfhrhhomheppfgvihhluehr ohifnhcuoehnvghilhgssehofihnmhgrihhlrdhnvghtqeenucggtffrrghtthgvrhhnpe evveekffduueevhfeigefhgfdukedtleekjeeitdejudfgueekvdekffdvfedvudenucev lhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehnvghilhgsse hofihnmhgrihhlrdhnvghtpdhnsggprhgtphhtthhopedujedpmhhouggvpehsmhhtphho uhhtpdhrtghpthhtohepvhhirhhoseiivghnihhvrdhlihhnuhigrdhorhhgrdhukhdprh gtphhtthhopehlihhnuhigqdhunhhiohhnfhhssehvghgvrhdrkhgvrhhnvghlrdhorhhg pdhrtghpthhtoheplhhinhhugidqnhhfshesvhhgvghrrdhkvghrnhgvlhdrohhrghdprh gtphhtthhopehlihhnuhigqdhfshguvghvvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhg pdhrtghpthhtoheplhhinhhugidqvghfihesvhhgvghrrdhkvghrnhgvlhdrohhrghdprh gtphhtthhopehlihhnuhigqdhkvghrnhgvlhesvhhgvghrrdhkvghrnhgvlhdprhgtphht thhopehmihhklhhoshesshiivghrvgguihdrhhhupdhrtghpthhtohepjhgrtghksehsuh hsvgdrtgiipdhrtghpthhtohepjhhksehoiihlrggsshdrohhrgh X-ME-Proxy: Feedback-ID: i9d664b8f:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Sun, 26 Apr 2026 23:37:02 -0400 (EDT) From: NeilBrown To: Linus Torvalds , Alexander Viro , Christian Brauner , Jan Kara , Jeff Layton , Trond Myklebust , Anna Schumaker , Miklos Szeredi , Amir Goldstein , Jeremy Kerr , Ard Biesheuvel , Christoph Hellwig Cc: linux-efi@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-kernel@vger.kernel Subject: [PATCH v2 07/19] VFS: Add LOOKUP_SHARED flag. Date: Mon, 27 Apr 2026 13:29:40 +1000 Message-ID: <20260427033527.773006-8-neilb@ownmail.net> X-Mailer: git-send-email 2.50.0.107.gf914562f5916.dirty In-Reply-To: <20260427033527.773006-1-neilb@ownmail.net> References: <20260427033527.773006-1-neilb@ownmail.net> Reply-To: NeilBrown Precedence: bulk X-Mailing-List: linux-efi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: NeilBrown Some ->lookup handlers will need to drop and retake the parent lock, so they can safely use d_alloc_parallel(). ->lookup can be called with the parent lock either exclusive or shared. A new flag, LOOKUP_SHARED, tells ->lookup how the parent is locked. This is rather ugly, but will be gone soon after we move d_alloc_parallel() out of the directory lock as ->lookup() will *always* called with a shared lock on the parent. Signed-off-by: NeilBrown --- fs/namei.c | 7 ++++--- include/linux/namei.h | 3 ++- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index a6349b31fdb6..e77ba9d31857 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1928,7 +1928,7 @@ static noinline struct dentry *lookup_slow(const struct qstr *name, struct inode *inode = dir->d_inode; struct dentry *res; inode_lock_shared(inode); - res = __lookup_slow(name, dir, flags); + res = __lookup_slow(name, dir, flags | LOOKUP_SHARED); inode_unlock_shared(inode); return res; } @@ -1942,7 +1942,7 @@ static struct dentry *lookup_slow_killable(const struct qstr *name, if (inode_lock_shared_killable(inode)) return ERR_PTR(-EINTR); - res = __lookup_slow(name, dir, flags); + res = __lookup_slow(name, dir, flags | LOOKUP_SHARED); inode_unlock_shared(inode); return res; } @@ -4413,6 +4413,7 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file, struct dentry *dentry; int error, create_error = 0; umode_t mode = op->mode; + unsigned int shared_flag = (op->open_flag & O_CREAT) ? 0 : LOOKUP_SHARED; if (unlikely(IS_DEADDIR(dir_inode))) return ERR_PTR(-ENOENT); @@ -4480,7 +4481,7 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file, if (d_in_lookup(dentry)) { struct dentry *res = dir_inode->i_op->lookup(dir_inode, dentry, - nd->flags); + nd->flags | shared_flag); d_lookup_done(dentry); if (unlikely(res)) { if (IS_ERR(res)) { diff --git a/include/linux/namei.h b/include/linux/namei.h index 2ad6dd9987b9..b3346a513d8f 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -37,8 +37,9 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT}; #define LOOKUP_CREATE BIT(17) /* ... in object creation */ #define LOOKUP_EXCL BIT(18) /* ... in target must not exist */ #define LOOKUP_RENAME_TARGET BIT(19) /* ... in destination of rename() */ +#define LOOKUP_SHARED BIT(20) /* Parent lock is held shared */ -/* 4 spare bits for intent */ +/* 3 spare bits for intent */ /* Scoping flags for lookup. */ #define LOOKUP_NO_SYMLINKS BIT(24) /* No symlink crossing. */ -- 2.50.0.107.gf914562f5916.dirty