From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 0B06CC433DF for ; Tue, 25 Aug 2020 17:49:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9FCC207BC for ; Tue, 25 Aug 2020 17:49:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=falconindy.com header.i=@falconindy.com header.b="G1bBBLMv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726158AbgHYRta (ORCPT ); Tue, 25 Aug 2020 13:49:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726090AbgHYRt2 (ORCPT ); Tue, 25 Aug 2020 13:49:28 -0400 Received: from mail-qv1-xf43.google.com (mail-qv1-xf43.google.com [IPv6:2607:f8b0:4864:20::f43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F387AC061574 for ; Tue, 25 Aug 2020 10:49:26 -0700 (PDT) Received: by mail-qv1-xf43.google.com with SMTP id j10so5890305qvo.13 for ; Tue, 25 Aug 2020 10:49:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=falconindy.com; s=google; h=date:from:to:cc:subject:message-id:mail-followup-to:references :mime-version:content-disposition:in-reply-to; bh=lxNeX3DFf7e79poQquA0+jjs1dndB7RaKQWPGDwiN6M=; b=G1bBBLMveJH8E90ZBuqDE8A0To9sk7WpvvCBcdKTY7QQ5KYd2KicQ3JU2JF/k+zHtI YWWt6tKAa8IjrqenccabVVQAqgEvUdDWizzuO8r1DkDY7OXLAnlzJsVvSeKgdXx1RpGZ Q7QD7Qrj+r0tFV+rpgZaIoQZCxaopmmfln4LQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id :mail-followup-to:references:mime-version:content-disposition :in-reply-to; bh=lxNeX3DFf7e79poQquA0+jjs1dndB7RaKQWPGDwiN6M=; b=JkPjFZ3JQoCe/pVlEY1M06vRA1J2TN5fKBESVg8aiWsUcHIPjNNtC53bkFws1eLUc3 q09aTxLkx0d7I3zdbacIKJFnV4BhzDkLpAr5ohdpyfUN+TYo+YxUG+/Dma7RepesUnHA ItL/DAy9uzU2kHzBjNGrIiHW4MBHcUzDm2fW25GQRZhyPqzRhCz4LHszCNt7uIIM5bI8 Gy2tL4S5Wk1j/EdK2aofteItVd2DCMVfBSC/KSFnxniG87soW9YyzNhHk1Hr0N5PzowO kx8oy8QkQWluxlyYmBN3ebKJXa+4tOFBnJ8MU7G0GjTn3xUojpD6JGEiPsGOR//eWU3Z MbUw== X-Gm-Message-State: AOAM532ooUWHAS2LVTkj0PtzUqUTpu1md/yhpO2Mlx7mjOEiU5y0Zuid BaeN40qc/bzrpkCkdFRIRw7xxA== X-Google-Smtp-Source: ABdhPJysOcbGcmsWGaToBb2+kvLeV9W2iKDaFuOqOH+ETFadkYgqX3zJqUq5LU+zLXehRG2GOC0R8g== X-Received: by 2002:a05:6214:1467:: with SMTP id c7mr10418763qvy.233.1598377764531; Tue, 25 Aug 2020 10:49:24 -0700 (PDT) Received: from localhost ([2604:2000:1406:11:b76a:7f6b:de1a:9b75]) by smtp.gmail.com with ESMTPSA id t25sm14200309qtp.22.2020.08.25.10.49.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Aug 2020 10:49:23 -0700 (PDT) Date: Tue, 25 Aug 2020 13:49:22 -0400 From: Dave Reisner To: Lucas De Marchi Cc: Torge Matthies , linux-modules , Luis Chamberlain , Dave Reisner Subject: Re: [PATCH] Add Zstandard support Message-ID: <20200825174922.GA728@rampage> Mail-Followup-To: Lucas De Marchi , Torge Matthies , linux-modules , Luis Chamberlain , Dave Reisner References: <20200821224501.196413-1-openglfreak@googlemail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-modules@vger.kernel.org Precedence: bulk List-ID: On Tue, Aug 25, 2020 at 10:12:57AM -0700, Lucas De Marchi wrote: > Hi, > > On Fri, Aug 21, 2020 at 3:46 PM Torge Matthies > wrote: > > > > I was not able to find any existing zstd patch for kmod, so I wrote my own. > > thanks a lot for adding this. > > > > > I was struggling to get the C code below the 80 character line length limit, > > that's why I used gotos. I used descriptive label names, and it still looks > > clean enough in my opinion. > > Humn.. I'd rather prefer not to be on 80 chars than using some of the gotos, > but take a look below > > > > > I changed the style of the hackargs variable in autogen.sh to multiline > > because said line was becoming a bit long with the new --with-zstd arg > > added. > > ok > > > > > This patch has been running on my two Arch Linux installations (with an > > accompanying mkinitcpio patch) for several months over many kernel updates > > without any issues. > > great. Is Arch already using zstd for the kernel? Once this lands, is > it going to > zstd for modules? > > +Dave > No plans that I'm aware of. We currently use CONFIG_MODULE_COMPRESS_XZ=y to have Kbuild do the module compression for us at build time. Is Kbuild being updated to support zstd if/when this patch lands in a kmod release? Personally, I'd rather see less module compression, not more. This "flavor of the week" compression stuff makes me tired, and the way compression is implemented in userspace inhibits more important features like secure module loading via finit_module. dR > > Any additional testing and/or patch review would of course be appreciated. > > > > Signed-off-by: Torge Matthies > > --- > > .semaphore/semaphore.yml | 4 +- > > .travis.yml | 1 + > > Makefile.am | 4 +- > > autogen.sh | 9 ++- > > configure.ac | 13 +++- > > libkmod/libkmod-file.c | 119 +++++++++++++++++++++++++++++++++++ > > libkmod/libkmod.pc.in | 2 +- > > shared/util.c | 3 + > > testsuite/mkosi/mkosi.fedora | 1 + > > testsuite/test-util.c | 3 + > > 10 files changed, 153 insertions(+), 6 deletions(-) > > > > diff --git a/.semaphore/semaphore.yml b/.semaphore/semaphore.yml > > index db47ca1..fe1d78a 100644 > > --- a/.semaphore/semaphore.yml > > +++ b/.semaphore/semaphore.yml > > @@ -22,7 +22,7 @@ blocks: > > prologue: > > commands: > > - sudo apt update > > - - sudo apt --yes install docbook-xsl liblzma-dev zlib1g-dev cython linux-headers-generic libssl-dev > > + - sudo apt --yes install docbook-xsl libzstd-dev liblzma-dev zlib1g-dev cython linux-headers-generic libssl-dev > > - checkout > > > > epilogue: > > @@ -42,5 +42,5 @@ blocks: > > prologue: > > commands: > > - sudo apt update > > - - sudo apt --yes install docbook-xsl liblzma-dev zlib1g-dev cython linux-headers-generic libssl-dev > > + - sudo apt --yes install docbook-xsl libzstd-dev liblzma-dev zlib1g-dev cython linux-headers-generic libssl-dev > > - checkout > > diff --git a/.travis.yml b/.travis.yml > > index 02c753e..0fcce14 100644 > > --- a/.travis.yml > > +++ b/.travis.yml > > @@ -14,6 +14,7 @@ matrix: > > before_install: > > - sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y > > - sudo apt-get update -qq > > + - sudo apt-get install -qq libzstd-dev > > - sudo apt-get install -qq liblzma-dev > > - sudo apt-get install -qq zlib1g-dev > > - sudo apt-get install -qq xsltproc docbook-xsl > > diff --git a/Makefile.am b/Makefile.am > > index 8eadb99..37d840b 100644 > > --- a/Makefile.am > > +++ b/Makefile.am > > @@ -31,6 +31,8 @@ SED_PROCESS = \ > > -e 's,@exec_prefix\@,$(exec_prefix),g' \ > > -e 's,@libdir\@,$(libdir),g' \ > > -e 's,@includedir\@,$(includedir),g' \ > > + -e 's,@libzstd_CFLAGS\@,${libzstd_CFLAGS},g' \ > > + -e 's,@libzstd_LIBS\@,${libzstd_LIBS},g' \ > > -e 's,@liblzma_CFLAGS\@,${liblzma_CFLAGS},g' \ > > -e 's,@liblzma_LIBS\@,${liblzma_LIBS},g' \ > > -e 's,@zlib_CFLAGS\@,${zlib_CFLAGS},g' \ > > @@ -90,7 +92,7 @@ libkmod_libkmod_la_DEPENDENCIES = \ > > ${top_srcdir}/libkmod/libkmod.sym > > libkmod_libkmod_la_LIBADD = \ > > shared/libshared.la \ > > - ${liblzma_LIBS} ${zlib_LIBS} ${libcrypto_LIBS} > > + ${libzstd_LIBS} ${liblzma_LIBS} ${zlib_LIBS} ${libcrypto_LIBS} > > > > noinst_LTLIBRARIES += libkmod/libkmod-internal.la > > libkmod_libkmod_internal_la_SOURCES = $(libkmod_libkmod_la_SOURCES) > > diff --git a/autogen.sh b/autogen.sh > > index 67b119f..e4997c4 100755 > > --- a/autogen.sh > > +++ b/autogen.sh > > @@ -32,7 +32,14 @@ fi > > > > cd $oldpwd > > > > -hackargs="--enable-debug --enable-python --with-xz --with-zlib --with-openssl" > > +hackargs="\ > > +--enable-debug \ > > +--enable-python \ > > +--with-zstd \ > > +--with-xz \ > > +--with-zlib \ > > +--with-openssl \ > > +" > > > > if [ "x$1" = "xc" ]; then > > shift > > diff --git a/configure.ac b/configure.ac > > index 4a65d6b..a49f6b9 100644 > > --- a/configure.ac > > +++ b/configure.ac > > @@ -83,6 +83,17 @@ AC_ARG_WITH([rootlibdir], > > [], [with_rootlibdir=$libdir]) > > AC_SUBST([rootlibdir], [$with_rootlibdir]) > > > > +AC_ARG_WITH([zstd], > > + AS_HELP_STRING([--with-zstd], [handle Zstandard-compressed modules @<:@default=disabled@:>@]), > > + [], [with_zstd=no]) > > +AS_IF([test "x$with_zstd" != "xno"], [ > > + PKG_CHECK_MODULES([libzstd], [libzstd >= 1.4.4]) > > + AC_DEFINE([ENABLE_ZSTD], [1], [Enable Zstandard for modules.]) > > +], [ > > + AC_MSG_NOTICE([Zstandard support not requested]) > > +]) > > +CC_FEATURE_APPEND([with_features], [with_zstd], [ZSTD]) > > + > > AC_ARG_WITH([xz], > > AS_HELP_STRING([--with-xz], [handle Xz-compressed modules @<:@default=disabled@:>@]), > > [], [with_xz=no]) > > @@ -307,7 +318,7 @@ AC_MSG_RESULT([ > > tools: ${enable_tools} > > python bindings: ${enable_python} > > logging: ${enable_logging} > > - compression: xz=${with_xz} zlib=${with_zlib} > > + compression: zstd=${with_zstd} xz=${with_xz} zlib=${with_zlib} > > debug: ${enable_debug} > > coverage: ${enable_coverage} > > doc: ${enable_gtk_doc} > > diff --git a/libkmod/libkmod-file.c b/libkmod/libkmod-file.c > > index 5eeba6a..1a2e753 100644 > > --- a/libkmod/libkmod-file.c > > +++ b/libkmod/libkmod-file.c > > @@ -26,6 +26,9 @@ > > #include > > #include > > #include > > +#ifdef ENABLE_ZSTD > > +#include > > +#endif > > #ifdef ENABLE_XZ > > #include > > #endif > > @@ -45,6 +48,9 @@ struct file_ops { > > }; > > > > struct kmod_file { > > +#ifdef ENABLE_ZSTD > > + bool zstd_used; > > +#endif > > #ifdef ENABLE_XZ > > bool xz_used; > > #endif > > @@ -60,6 +66,116 @@ struct kmod_file { > > struct kmod_elf *elf; > > }; > > > > +#ifdef ENABLE_ZSTD > > +static int load_zstd(struct kmod_file *file) > > +{ > > + ZSTD_DStream *dstr = NULL; > > + size_t in_buf_size, out_buf_min_size, out_buf_size; > > + uint8_t *in_buf = NULL, *out_buf = NULL; > > + ZSTD_inBuffer zst_input; > > + ZSTD_outBuffer zst_output; > > + int ret = -EINVAL; > > + > > + dstr = ZSTD_createDStream(); > > + if (dstr == NULL) { > > + ERR(file->ctx, "zstd: Failed to create decompression stream\n"); > > + ret = -EINVAL; > > + goto out; > > + } > > + > > + in_buf_size = ZSTD_initDStream(dstr); > > + in_buf = malloc(in_buf_size); > > + if (in_buf == NULL) { > > + ERR(file->ctx, "zstd: %s\n", strerror(ENOMEM)); > > no big deal, but malloc() should set errno, so you could use > ret = -errno before printing and then use %m in the message. > > Same thing in other places. > > > + ret = -ENOMEM; > > + goto out; > > + } > > + > > + out_buf_size = out_buf_min_size = ZSTD_DStreamOutSize(); > > + out_buf = malloc(out_buf_size); > > + if (out_buf == NULL) { > > + ERR(file->ctx, "zstd: %s\n", strerror(ENOMEM)); > > + ret = -ENOMEM; > > + goto out; > > + } > > + > > + zst_input.src = in_buf; > > + zst_output.dst = out_buf; > > + zst_output.size = out_buf_size; > > + zst_output.pos = 0; > > + while (true) { > > + ssize_t rdret; > > + size_t dsret; > > + uint8_t *tmp; > > + > > + rdret = read(file->fd, in_buf, in_buf_size); > > + if (rdret < 0) { > > + ret = -errno; > > + goto out; > > + } > > + if (rdret == 0) > > + break; > > + > > + zst_input.size = rdret; > > + zst_input.pos = 0; > > + > > + if (zst_output.size - zst_output.pos < out_buf_min_size) > > + goto realloc_buffer; > > this could be a helper function to realloc the buffer. It can even be shared > for the first alloc if you initialize zst_output.size to 0.. Then you > have something like: > > > + > > +try_decompress: > > + dsret = ZSTD_decompressStream(dstr, &zst_output, &zst_input); > > + if (ZSTD_isError(dsret)) { > > + ERR(file->ctx, "zstd: %s\n", ZSTD_getErrorName(dsret)); > > + ret = -EINVAL; > > + goto out; > > + } > > + > > + if (zst_output.pos < zst_output.size > > + && zst_output.size - zst_output.pos > > + >= out_buf_min_size) { > > + if (zst_input.pos < zst_input.size) > > + goto try_decompress; > > this looks like a while/for loop. Could even be in a helper function > > > > + else > > + continue; > > + } > > + > > +realloc_buffer: > > + tmp = realloc(out_buf, out_buf_size + out_buf_min_size); > > + if (tmp == NULL) { > > + ret = -errno; > > + goto out; > > + } > > + out_buf_size += out_buf_min_size; > > + out_buf = tmp; > > + zst_output.dst = out_buf; > > + zst_output.size = out_buf_size; > > + goto try_decompress; > > + } > > + > > + ZSTD_freeDStream(dstr); > > + free(in_buf); > > + file->zstd_used = true; > > + file->memory = out_buf; > > + file->size = zst_output.pos; > > + return 0; > > +out: > > + if (dstr != NULL) > > + ZSTD_freeDStream(dstr); > > + free(out_buf); > > + free(in_buf); > > + return ret; > > +} > > + > > +static void unload_zstd(struct kmod_file *file) > > +{ > > + if (!file->zstd_used) > > + return; > > + free(file->memory); > > +} > > + > > +static const char magic_zstd[] = {0x28, 0xB5, 0x2F, 0xFD}; > > +#endif > > + > > #ifdef ENABLE_XZ > > static void xz_uncompress_belch(struct kmod_file *file, lzma_ret ret) > > { > > @@ -238,6 +354,9 @@ static const struct comp_type { > > const char *magic_bytes; > > const struct file_ops ops; > > } comp_types[] = { > > +#ifdef ENABLE_ZSTD > > + {sizeof(magic_zstd), magic_zstd, {load_zstd, unload_zstd}}, > > +#endif > > #ifdef ENABLE_XZ > > {sizeof(magic_xz), magic_xz, {load_xz, unload_xz}}, > > #endif > > diff --git a/libkmod/libkmod.pc.in b/libkmod/libkmod.pc.in > > index e4fdf21..3acca6a 100644 > > --- a/libkmod/libkmod.pc.in > > +++ b/libkmod/libkmod.pc.in > > @@ -7,5 +7,5 @@ Name: libkmod > > Description: Library to deal with kernel modules > > Version: @VERSION@ > > Libs: -L${libdir} -lkmod > > -Libs.private: @liblzma_LIBS@ @zlib_LIBS@ > > +Libs.private: @libzstd_LIBS@ @liblzma_LIBS@ @zlib_LIBS@ > > Cflags: -I${includedir} > > diff --git a/shared/util.c b/shared/util.c > > index fd2028d..b487b5f 100644 > > --- a/shared/util.c > > +++ b/shared/util.c > > @@ -45,6 +45,9 @@ static const struct kmod_ext { > > #endif > > #ifdef ENABLE_XZ > > {".ko.xz", sizeof(".ko.xz") - 1}, > > +#endif > > +#ifdef ENABLE_ZSTD > > + {".ko.zst", sizeof(".ko.zst") - 1}, > > #endif > > { } > > }; > > diff --git a/testsuite/mkosi/mkosi.fedora b/testsuite/mkosi/mkosi.fedora > > index 5252f87..7a2ee5e 100644 > > --- a/testsuite/mkosi/mkosi.fedora > > +++ b/testsuite/mkosi/mkosi.fedora > > @@ -19,6 +19,7 @@ BuildPackages = > > make > > pkgconf-pkg-config > > xml-common > > + libzstd-devel > > xz-devel > > zlib-devel > > openssl-devel > > diff --git a/testsuite/test-util.c b/testsuite/test-util.c > > index 5e25e58..621446b 100644 > > --- a/testsuite/test-util.c > > +++ b/testsuite/test-util.c > > @@ -156,6 +156,9 @@ static int test_path_ends_with_kmod_ext(const struct test *t) > > #endif > > #ifdef ENABLE_XZ > > { "/bla.ko.xz", true }, > > +#endif > > +#ifdef ENABLE_ZSTD > > + { "/bla.ko.zst", true }, > > I think we want a zstd-compressed module in the testsuite as well to test this. > > thanks > Lucas De Marchi > > > #endif > > { "/bla.ko.x", false }, > > { "/bla.ko.", false }, > > -- > > 2.28.0 > >