From patchwork Fri Jan 22 20:47:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Sandoval X-Patchwork-Id: 12040609 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A79BEC433E0 for ; Fri, 22 Jan 2021 21:11:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84FA923AF8 for ; Fri, 22 Jan 2021 21:11:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728444AbhAVVLS (ORCPT ); Fri, 22 Jan 2021 16:11:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49574 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731047AbhAVUxc (ORCPT ); Fri, 22 Jan 2021 15:53:32 -0500 Received: from mail-pl1-x630.google.com (mail-pl1-x630.google.com [IPv6:2607:f8b0:4864:20::630]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0CEAEC0698D2 for ; Fri, 22 Jan 2021 12:48:38 -0800 (PST) Received: by mail-pl1-x630.google.com with SMTP id h15so1484712pli.8 for ; Fri, 22 Jan 2021 12:48:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osandov-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=t4U7hox/ox8NJiCD09kdKyflNUgetq9XNrvX185hJfE=; b=iW4TXb5oPqGQcV/qhoRMlEInT5Sa9xhW4WR/LNznUpCaUXsDodccPB5wG/jlEeKJks +MR2AsCl1N2lI+LOiT64sVYzRs4DUDtJ4WDFSXfj6Zc8VQy47j0WXqKbDJc5nYNdCCcI AcUrC7ViZ5AreRLR/c2Cgj9cRMpXg0rgHmux4/9X10ct144cy4LE6PDcgIS4MRiEfcDP wWj7Jl1uzz/J/VWsDLTvizsdY9Pv1xjTUHfH9SsBHSbqxR5bEPUfQz9yIYQYq3oZdDNE 8SVgJBBg/D+8hRKLmJKrFnJjzc7qSdLo7CfYJDoaQgVwGfENFV7CpvZoBlDZ58AKC1p/ hDBA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=t4U7hox/ox8NJiCD09kdKyflNUgetq9XNrvX185hJfE=; b=hJQRCMtH9xGqJ7j84hls6UwHiDtZF24aXW3b8A/oSiVtbJ+9y5IMLiSaSh9hUCQs2V q715S24+yFJWHE+cbRSf+aOio4sps0r4e5QWRSR2f9nICn78qVKHht89ShoDj9KxVQTr oPiDmn7xUYBMfiO+i8ZJ1OTSAkk12IW5/vNIGfET3LvyfDIj+7AWFrHd6N2grPvXEUfm tFCxYu4J358v/MR3FhJeEQkwh1yIniykBlVAaW/Eu2gxUeaw4UG1YQFxHrl++bvmWCek OfZpJpR8xx4u7S+ZFMLxx86UMKy6R33ae4kRXd48Ztcw1PDDYfA+3uclVzRbwAkElM56 12Ow== X-Gm-Message-State: AOAM530iMx8Oixh0FnIywWb6UOf3SBhwWG+KiyHLJH+pBlxU6nNVhVpR vQatQFPldzz08k65PXLqKAdYm+YAdI/Edg== X-Google-Smtp-Source: ABdhPJwcshFHSUnx4T8H9XICsfSpJItoAwj2IFubcr8mhUD8QdwvPO0JW2ZkFSmUBW3+8wGSQGbKhA== X-Received: by 2002:a17:902:694c:b029:da:afba:beab with SMTP id k12-20020a170902694cb02900daafbabeabmr6810541plt.32.1611348516992; Fri, 22 Jan 2021 12:48:36 -0800 (PST) Received: from relinquished.tfbnw.net ([2620:10d:c090:400::5:ea88]) by smtp.gmail.com with ESMTPSA id y16sm9865617pfb.83.2021.01.22.12.48.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Jan 2021 12:48:35 -0800 (PST) From: Omar Sandoval To: linux-btrfs@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH v3 05/11] btrfs-progs: receive: add stub implementation for pwritev2 Date: Fri, 22 Jan 2021 12:47:51 -0800 Message-Id: X-Mailer: git-send-email 2.30.0 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Boris Burkov Encoded writes in receive will use pwritev2. It is possible that the system libc does not export this function, so we stub it out and detect whether to build the stub code with autoconf. This syscall has special semantics in x32 (no hi lo, just takes loff_t) so we have to detect that case and use the appropriate arguments. Signed-off-by: Boris Burkov --- Makefile | 4 ++-- configure.ac | 1 + stubs.c | 24 ++++++++++++++++++++++++ stubs.h | 11 +++++++++++ 4 files changed, 38 insertions(+), 2 deletions(-) create mode 100644 stubs.c create mode 100644 stubs.h diff --git a/Makefile b/Makefile index e288a336..7c0971f7 100644 --- a/Makefile +++ b/Makefile @@ -173,12 +173,12 @@ libbtrfs_objects = common/send-stream.o common/send-utils.o kernel-lib/rbtree.o kernel-lib/raid56.o kernel-lib/tables.o \ common/device-scan.o common/path-utils.o \ common/utils.o libbtrfsutil/subvolume.o libbtrfsutil/stubs.o \ - crypto/hash.o crypto/xxhash.o $(CRYPTO_OBJECTS) + crypto/hash.o crypto/xxhash.o $(CRYPTO_OBJECTS) stubs.o libbtrfs_headers = common/send-stream.h common/send-utils.h send.h kernel-lib/rbtree.h btrfs-list.h \ crypto/crc32c.h kernel-lib/list.h kerncompat.h \ kernel-lib/radix-tree.h kernel-lib/sizes.h kernel-lib/raid56.h \ common/extent-cache.h kernel-shared/extent_io.h ioctl.h \ - kernel-shared/ctree.h btrfsck.h version.h + kernel-shared/ctree.h btrfsck.h version.h stubs.h libbtrfsutil_major := $(shell sed -rn 's/^\#define BTRFS_UTIL_VERSION_MAJOR ([0-9])+$$/\1/p' libbtrfsutil/btrfsutil.h) libbtrfsutil_minor := $(shell sed -rn 's/^\#define BTRFS_UTIL_VERSION_MINOR ([0-9])+$$/\1/p' libbtrfsutil/btrfsutil.h) libbtrfsutil_patch := $(shell sed -rn 's/^\#define BTRFS_UTIL_VERSION_PATCH ([0-9])+$$/\1/p' libbtrfsutil/btrfsutil.h) diff --git a/configure.ac b/configure.ac index 39f93040..d43eb91f 100644 --- a/configure.ac +++ b/configure.ac @@ -57,6 +57,7 @@ AC_CHECK_FUNCS([openat], [], [AC_MSG_ERROR([cannot find openat() function])]) AC_CHECK_FUNCS([reallocarray]) +AC_CHECK_FUNCS([pwritev2]) m4_ifndef([PKG_PROG_PKG_CONFIG], [m4_fatal([Could not locate the pkg-config autoconf diff --git a/stubs.c b/stubs.c new file mode 100644 index 00000000..ab68a411 --- /dev/null +++ b/stubs.c @@ -0,0 +1,24 @@ +#if HAVE_PWRITEV2 != 1 + +#include "stubs.h" + +#include "kerncompat.h" + +#include +#include +#include + +ssize_t pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, + int flags) +{ +/* these conditions indicate an x32 system, which has a different pwritev2 */ +#if defined(__x86_64__) && defined(__ILP32__) + return syscall(SYS_pwritev2, fd, iov, iovcnt, offset, flags); +#else + unsigned long hi = offset >> (BITS_PER_LONG / 2) >> (BITS_PER_LONG / 2); + unsigned long lo = offset; + + return syscall(SYS_pwritev2, fd, iov, iovcnt, lo, hi, flags); +#endif // X32 +} +#endif /* HAVE_PWRIVEV2 */ diff --git a/stubs.h b/stubs.h new file mode 100644 index 00000000..b39f8a69 --- /dev/null +++ b/stubs.h @@ -0,0 +1,11 @@ +#ifndef _BTRFS_STUBS_H +#define _BTRFS_STUBS_H + +#include + +struct iovec; + +ssize_t pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, + int flags); + +#endif