From nobody Mon Jul 24 22:03:18 2023 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4R8vLH20dwz4pTjh; Mon, 24 Jul 2023 22:03:19 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4R8vLH1Jnkz4Dh0; Mon, 24 Jul 2023 22:03:19 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1690236199; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=FhE78cROgk3SPI2S0bWRlYBYq7mmebsLa7IUDWS3vUw=; b=q5c89nOTe7KTKu9T4VHIwbr6/WVzcPc2kKFMTgQe0XXitQaMNgvNALVSZGy/mQVCrdUVZs GCUCV4WFZMevRkn/nEoPBT0NPVu/MDue/+ZcLYegpQHOuxKWkiTxyaCH5eOwlCxclNjOt3 9kzQo8XQiPaWFzBJKDPtazIVkc2XlOzdSdD7vDPNJ+T6w8MF7Bodb67M0/aN8APjCZYBDK ZbclxojhDdndug1cvp4JMbaKJjSMDmCuZBsk2N1nvENQSI5DYfC3YvSJbsyeCvzedFf7un g5geH/F8vQMgWG7Cvfszze/wyZ3lRwOKsjtXaHPpHt3m0MoiK6ELbpenc1ZU5Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1690236199; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=FhE78cROgk3SPI2S0bWRlYBYq7mmebsLa7IUDWS3vUw=; b=KpBljSXHWr3p+L7eEeBREEbMPwt7oS/Ik27dmaXnUGiexEwQbT0yssQSTKrCEz1Ob/5XY9 b8P6vD8fXr17seBUMmQH9ifztu9pu64jVUPW+MLGex+n6mz0rfFDLyf1h1iFMBF4Zba1Wg mQOfJlpoSI11FjoRhpYxDQUt9QXYa+qIKLDDOk2/nDsRMyUJBvLXpt9CyjJixqPovz3ZyD 8jmGdf9nBaUPF+NuveXk3K2AapxPTz4N5t93ohuMeJyPR7G2hF+V8NW6/KrtWAZpPFyaRb Q6eix51MMC+5P0X8mB4P14Yb9mtwxzdEe7VFIJOufQySh4RqQKNr5+QdYDRuFQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1690236199; a=rsa-sha256; cv=none; b=Zbshg3gA1Eu+NZcaCoUVxThqgnVjG8Kh8N+3ObInZ/L8bXGRcQY5ZiKDPjrh+/x6wSqvJE nHawXcjkjhH0++vzb6PEZtBv3IWLmzW8+ispjK8GU4s1XbnOmkqcJSgYYW/E2aDPrvAYFb Ap5tn0fYrmO5LElytheEiaIwOYqfxcqG1LBQzoSm2Td5gzugHHZyCM2UsfoESRAO5Xr1Ml RYr+nqKq9co1btxZ+vqqPRuVYU09pyWX1fOpJNn/0HIWJ5Nkaz/vv7UOlEnVrLss27vaYy 4fy6PfGr8eLzVAc1885bD8T6iFok3i7EsBR3VWhYczdMspGpltowAHs/EXjn+g== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4R8vLH0QQ2zZt8; Mon, 24 Jul 2023 22:03:19 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 36OM3ICY009523; Mon, 24 Jul 2023 22:03:18 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 36OM3IwQ009522; Mon, 24 Jul 2023 22:03:18 GMT (envelope-from git) Date: Mon, 24 Jul 2023 22:03:18 GMT Message-Id: <202307242203.36OM3IwQ009522@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Konstantin Belousov Subject: git: 5b353925ff61 - main - vnode read(2)/write(2): acquire rangelock regardless of do_vn_io_fault() List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: kib X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 5b353925ff61b9ddb97bb453ba75278b578ed7d9 Auto-Submitted: auto-generated The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=5b353925ff61b9ddb97bb453ba75278b578ed7d9 commit 5b353925ff61b9ddb97bb453ba75278b578ed7d9 Author: Konstantin Belousov AuthorDate: 2023-07-23 15:55:50 +0000 Commit: Konstantin Belousov CommitDate: 2023-07-24 22:02:59 +0000 vnode read(2)/write(2): acquire rangelock regardless of do_vn_io_fault() To ensure atomicity of reads against parallel writes and truncates, vnode lock was not enough at least since introduction of vn_io_fault(). That code only take rangelock when it was possible that vn_read() and vn_write() could drop the vnode lock. At least since the introduction of VOP_READ_PGCACHE() which generally does not lock the vnode at all, rangelocks become required even for filesystems that do not need vn_io_fault() workaround. For instance, tmpfs. PR: 272678 Analyzed and reviewed by: Andrew Gierth Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D41158 --- sys/kern/vfs_vnops.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c index 83e95731d7c4..306840ff0357 100644 --- a/sys/kern/vfs_vnops.c +++ b/sys/kern/vfs_vnops.c @@ -1443,6 +1443,7 @@ vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred, void *rl_cookie; struct vn_io_fault_args args; int error; + bool rl_locked; doio = uio->uio_rw == UIO_READ ? vn_read : vn_write; vp = fp->f_vnode; @@ -1465,12 +1466,7 @@ vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred, } foffset_lock_uio(fp, uio, flags); - if (do_vn_io_fault(vp, uio)) { - args.kind = VN_IO_FAULT_FOP; - args.args.fop_args.fp = fp; - args.args.fop_args.doio = doio; - args.cred = active_cred; - args.flags = flags | FOF_OFFSET; + if (vp->v_type == VREG) { if (uio->uio_rw == UIO_READ) { rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset, uio->uio_offset + uio->uio_resid); @@ -1482,11 +1478,22 @@ vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred, rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset, uio->uio_offset + uio->uio_resid); } + rl_locked = true; + } else { + rl_locked = false; + } + if (do_vn_io_fault(vp, uio)) { + args.kind = VN_IO_FAULT_FOP; + args.args.fop_args.fp = fp; + args.args.fop_args.doio = doio; + args.cred = active_cred; + args.flags = flags | FOF_OFFSET; error = vn_io_fault1(vp, uio, &args, td); - vn_rangelock_unlock(vp, rl_cookie); } else { error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td); } + if (rl_locked) + vn_rangelock_unlock(vp, rl_cookie); foffset_unlock_uio(fp, uio, flags); return (error); }