From: Richard Jones Date: Mon, 15 Jun 2009 10:50:35 +0000 (+0100) Subject: Experimental implementation of the supermin appliance (passes most tests). X-Git-Tag: 1.0.46~2 X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=commitdiff_plain;h=414aa67f2bcbbc5009b92f32611aa9196836736b Experimental implementation of the supermin appliance (passes most tests). --- diff --git a/.gitignore b/.gitignore index b64c377..3e5ba21 100644 --- a/.gitignore +++ b/.gitignore @@ -20,8 +20,14 @@ ChangeLog Makefile.in Makefile aclocal.m4 +appliance/guestfs-supermin-helper appliance/initramfs.*.img +appliance/initramfs.*.supermin.hostfiles +appliance/kmod.whitelist appliance/make.sh +appliance/supermin-make.sh +appliance/supermin-split.sh +appliance/supermin.incfiles appliance/update.sh appliance/vmlinuz.* autom4te.cache diff --git a/appliance/Makefile.am b/appliance/Makefile.am index 5dd6521..3362992 100644 --- a/appliance/Makefile.am +++ b/appliance/Makefile.am @@ -16,20 +16,37 @@ # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. EXTRA_DIST = \ - make.sh update.sh + make.sh update.sh supermin-split.sh supermin-make.sh # Build the root filesystem (appliance). # Currently this is arch-dependent, so it seems like putting it in # $(libdir) is best. When we build cross-architecture filesystems we # should probably move them to $(datadir). - fsdir = $(libdir)/guestfs - +fs_DATA = $(APPLIANCE_FILES) + +# These are the resulting output files from the whole process: +# VMLINUZ kernel for the full appliance +# INITRAMFSIMG initramfs (ie. root fs) for the full appliance +# For details of the supermin appliance, read the README file: +# SUPERMINIMG initramfs (ie. partial root fs) for the supermin appliance +# SUPERMINFILES list of missing files (the ones we will pull out of the +# host filesystem at runtime) in the supermin appliance +APPLIANCE_FILES = $(INITRAMFSIMG) $(VMLINUZ) +if SUPERMIN +APPLIANCE_FILES += $(SUPERMINIMG) $(SUPERMINFILES) kmod.whitelist +bin_SCRIPTS = guestfs-supermin-helper +endif + +# Don't change these names - they must be the same as in '*.sh' scripts. INITRAMFSIMG = initramfs.$(REPO).$(host_cpu).img VMLINUZ = vmlinuz.$(REPO).$(host_cpu) +if SUPERMIN +SUPERMINIMG = initramfs.$(REPO).$(host_cpu).supermin.img +SUPERMINFILES = initramfs.$(REPO).$(host_cpu).supermin.hostfiles +endif -fs_DATA = $(INITRAMFSIMG) $(VMLINUZ) - +# This is for building the normal appliance: $(INITRAMFSIMG) $(VMLINUZ): $(top_builddir)/initramfs/fakeroot.log $(top_builddir)/initramfs/fakeroot.log: make.sh kmod.whitelist @@ -37,15 +54,49 @@ $(top_builddir)/initramfs/fakeroot.log: make.sh kmod.whitelist -mv $(VMLINUZ) $(VMLINUZ).bak if ! bash make.sh; then rm -f $@; exit 1; fi -$(INITRAMFSIMG): $(top_builddir)/initramfs/fakeroot.log $(top_builddir)/daemon/guestfsd +$(INITRAMFSIMG): $(top_builddir)/initramfs/fakeroot.log $(top_builddir)/daemon/guestfsd update.sh rm -f $@ bash update.sh touch $@ -make.sh: make.sh.in +kmod.whitelist: kmod.whitelist.in + grep -v '^[[:space:]]*$$' < $< | grep -v '^#' > $@ + +# This is for building the supermin appliance. It has to be enabled +# specifically with './configure --enable-supermin'. You really need +# to read the README file. + +if SUPERMIN + +# First we need to decide which files go in and out of the supermin +# appliance. This decision is made by 'supermin-split.sh'. +$(SUPERMINFILES): supermin.incfiles +supermin.incfiles: $(top_builddir)/initramfs/fakeroot.log supermin-split.sh + rm -f supermin.incfiles $(SUPERMINFILES) + bash supermin-split.sh + +# Second we need to create a supermin appliance with just the included +# files (leaving out the host files, which we'll add back at runtime). +$(SUPERMINIMG): supermin.incfiles supermin-make.sh + rm -f $@ + bash supermin-make.sh + +endif + +# This should rebuild the scripts if the input files change, although +# it doesn't always seem to work. +%.sh: %.sh.in cd .. && ./config.status appliance/$@ + chmod +x $@ + +guestfs-supermin-helper: guestfs-supermin-helper.in + cd .. && ./config.status appliance/$@ + chmod +x $@ + +#---------------------------------------------------------------------- +# Extra rules for testing the appliance. -# Test-boot the image. +# Test-boot the appliance. test-boot: emptydisk qemu-system-$(host_cpu) \ @@ -75,7 +126,7 @@ test-boot-realistic: emptydisk # Make clean. -CLEANFILES = $(fs_DATA) +CLEANFILES = $(APPLIANCE_FILES) clean-local: rm -rf $(top_builddir)/initramfs diff --git a/appliance/guestfs-supermin-helper.in b/appliance/guestfs-supermin-helper.in new file mode 100755 index 0000000..1384ef6 --- /dev/null +++ b/appliance/guestfs-supermin-helper.in @@ -0,0 +1,80 @@ +#!/bin/bash - +# @configure_input@ +# Copyright (C) 2009 Red Hat Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +# Helper script which constructs the supermin appliance at runtime. + +unset CDPATH + +set -e + +# Source directory containing the supermin input files. +sourcedir=$(cd "$1" > /dev/null; pwd) + +# Output files. +kernel="$2" +initrd="$3" + +# Look for the kernel first. This is very unsophisticated: We +# just look for any kernel named vmlinuz-*.$host_cpu which has a +# corresponding /lib/modules/*.$host_cpu directory. + +for f in /boot/vmlinuz-*.@host_cpu@; do + b=$(basename "$f") + b=$(echo "$b" | sed 's,vmlinuz-,,') + modpath="/lib/modules/$b" + if [ -d "$modpath" ]; then + ln -sf "$f" "$kernel" + break + fi + modpath= +done + +if [ -z "$modpath" ]; then + echo "$0: failed to find a suitable kernel" >&2 + exit 1 +fi + +# The initrd consists of these components: +# (1) The base skeleton appliance that we constructed at build time. +# name = initramfs.@REPO@.@host_cpu@.supermin.img +# format = compressed cpio +# (2) The modules from modpath which are on the module whitelist. +# format = plain cpio +# (3) The host files which match wildcards in *.supermin.hostfiles. +# format = plain cpio + +cp "$sourcedir"/initramfs.@REPO@.@host_cpu@.supermin.img "$initrd" + +# Kernel modules (2). +exec 5<"$sourcedir"/kmod.whitelist +whitelist= +while read kmod 0<&5; do + whitelist="$whitelist -a -not -name $kmod" +done +exec 5<&- + +find "$modpath" -not -name '*.ko' -o \( -name '*.ko' $whitelist \) -a -print0 | + cpio --quiet -o -0 -H newc >> "$initrd" + +# Host files (3). + +(cd / && \ + ls -1df $( + cat "$sourcedir"/initramfs.@REPO@.@host_cpu@.supermin.hostfiles + ) 2>/dev/null | + cpio --quiet -o -H newc ) >> "$initrd" diff --git a/appliance/kmod.whitelist b/appliance/kmod.whitelist.in similarity index 100% rename from appliance/kmod.whitelist rename to appliance/kmod.whitelist.in diff --git a/appliance/make.sh.in b/appliance/make.sh.in index 8f3b212..9d77bea 100755 --- a/appliance/make.sh.in +++ b/appliance/make.sh.in @@ -80,18 +80,22 @@ rm -f $koutput # Don't need any keyboard maps. @FEBOOTSTRAP_RUN@ initramfs -- rm -rf /lib/kbd +# Remove anything in home directory. Because this is potentially +# liable to monstrous fuck-ups, we don't put a slash before 'home'. +(cd initramfs && echo home/*) | + xargs @FEBOOTSTRAP_RUN@ initramfs -- rm -rf + +# Remove /var/lib/yum stuff. +@FEBOOTSTRAP_RUN@ initramfs -- rm -rf /var/lib/yum + # Kernel modules take up nearly half of the image. Only include ones # which are on the whitelist. -grep -v '^[[:space:]]*$' < appliance/kmod.whitelist | - grep -v '^#' > kmod.whitelist.tmp -exec 5 $output-t +mv $output-t $output +ls -lh $output diff --git a/appliance/supermin-split.sh.in b/appliance/supermin-split.sh.in new file mode 100755 index 0000000..fe4ab6e --- /dev/null +++ b/appliance/supermin-split.sh.in @@ -0,0 +1,93 @@ +#!/bin/bash - +# @configure_input@ +# Copyright (C) 2009 Red Hat Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +# Decide which files will stay in the supermin appliance and which +# files will be pulled out of the host at runtime. +# +# Read the README file! +# +# The basic idea is that we create two output files, one containing +# the files that will stay, and the other listing the files that +# will be pulled from the host (ie. not go into the appliance now). +# +# The list of files that stay ('supermin.incfiles') is just a straight +# list of files and directories. +# +# The list of files that come from the host ('*.supermin.hostfiles') +# can include wildcards, to allow libraries to be upgraded on the +# host. + +unset CDPATH + +set -e + +cd @top_builddir@/initramfs + +incfiles=../appliance/supermin.incfiles +hostfiles=../appliance/initramfs.@REPO@.@host_cpu@.supermin.hostfiles + +exec 5>$incfiles +exec 6>$hostfiles + +# Note currently the initramfs contains ~2500 files, and none have +# "funny characters" in the names. So this is reasonable just to +# simplify the script. +for path in $(find -not -name fakeroot.log); do + dir=$(dirname "$path") + file=$(basename "$path") + + # All we're going to keep are the special files /init, the daemon, + # configuration files (/etc), devices and modifiable stuff (/var). + if [ "$path" = "./init" -o "$file" = "guestfsd" ]; then + echo "$path" >&5 + + elif [[ "$path" =~ '^\./etc' || "$path" =~ '^./dev' || "$path" =~ '^\./var' ]]; then + echo "$path" >&5 + + # Kernel modules are always copied in from the host, including all + # the dependency files. + elif [[ "$path" =~ '^\./lib/modules/' ]]; then + : + + elif [ -d "$path" ]; then + # Always write directory names to both output files. + echo "$path" >&5 + echo "$path" >&6 + + # Some libraries need fixed version numbers replaced by wildcards. + + elif [[ "$file" =~ '^ld-[.0-9]+\.so$' ]]; then + echo "$dir/ld-*.so" >&6 + + # libfoo-1.2.3.so + elif [[ "$file" =~ '^lib(.*)-[-.0-9]+\.so$' ]]; then + echo "$dir/lib${BASH_REMATCH[1]}-*.so" >&6 + + # libfoo-1.2.3.so.1.2.3 (but NOT '*.so.N') + elif [[ "$file" =~ '^lib(.*)-[-.0-9]+\.so\.([0-9]+)\.' ]]; then + echo "$dir/lib${BASH_REMATCH[1]}-*.so.${BASH_REMATCH[2]}.*" >&6 + + # libfoo.so.1.2.3 (but NOT '*.so.N') + elif [[ "$file" =~ '^lib(.*)\.so\.([0-9]+)\.' ]]; then + echo "$dir/lib${BASH_REMATCH[1]}.so.${BASH_REMATCH[2]}.*" >&6 + + else + # Anything else comes from the host directly. + echo "$path" >&6 + fi +done diff --git a/configure.ac b/configure.ac index e73799a..be1ed6b 100644 --- a/configure.ac +++ b/configure.ac @@ -480,6 +480,8 @@ AC_CONFIG_FILES([Makefile src/Makefile fish/Makefile po/Makefile.in examples/Makefile appliance/Makefile appliance/make.sh appliance/update.sh + appliance/supermin-split.sh appliance/supermin-make.sh + appliance/guestfs-supermin-helper images/Makefile capitests/Makefile regressions/Makefile @@ -495,7 +497,7 @@ AC_CONFIG_FILES([Makefile AC_OUTPUT dnl WTF? -chmod +x appliance/make.sh appliance/update.sh +chmod +x appliance/*.sh appliance/guestfs-supermin-helper dnl Produce summary. echo diff --git a/src/guestfs.c b/src/guestfs.c index fea8107..8f06d3b 100644 --- a/src/guestfs.c +++ b/src/guestfs.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include @@ -309,6 +310,12 @@ guestfs_close (guestfs_h *g) snprintf (filename, sizeof filename, "%s/sock", g->tmpdir); unlink (filename); + snprintf (filename, sizeof filename, "%s/initrd", g->tmpdir); + unlink (filename); + + snprintf (filename, sizeof filename, "%s/kernel", g->tmpdir); + unlink (filename); + rmdir (g->tmpdir); free (g->tmpdir); @@ -706,6 +713,46 @@ guestfs_add_cdrom (guestfs_h *g, const char *filename) return guestfs_config (g, "-cdrom", filename); } +/* Returns true iff file is contained in dir. */ +static int +dir_contains_file (const char *dir, const char *file) +{ + int dirlen = strlen (dir); + int filelen = strlen (file); + int len = dirlen+filelen+2; + char path[len]; + + snprintf (path, len, "%s/%s", dir, file); + return access (path, F_OK) == 0; +} + +/* Returns true iff every listed file is contained in 'dir'. */ +static int +dir_contains_files (const char *dir, ...) +{ + va_list args; + const char *file; + + va_start (args, dir); + while ((file = va_arg (args, const char *)) != NULL) { + if (!dir_contains_file (dir, file)) { + va_end (args); + return 0; + } + } + va_end (args); + return 1; +} + +static int build_supermin_appliance (guestfs_h *g, const char *path, char **kernel, char **initrd); + +static const char *kernel_name = "vmlinuz." REPO "." host_cpu; +static const char *initrd_name = "initramfs." REPO "." host_cpu ".img"; +static const char *supermin_name = + "initramfs." REPO "." host_cpu ".supermin.img"; +static const char *supermin_hostfiles_name = + "initramfs." REPO "." host_cpu ".supermin.hostfiles"; + int guestfs_launch (guestfs_h *g) { @@ -714,8 +761,6 @@ guestfs_launch (guestfs_h *g) size_t len; int wfd[2], rfd[2]; int tries; - const char *kernel_name = "vmlinuz." REPO "." host_cpu; - const char *initrd_name = "initramfs." REPO "." host_cpu ".img"; char *path, *pelem, *pend; char *kernel = NULL, *initrd = NULL; char unixsock[256]; @@ -732,7 +777,20 @@ guestfs_launch (guestfs_h *g) return -1; } - /* Search g->path for the kernel and initrd. */ + /* Make the temporary directory. */ + if (!g->tmpdir) { + g->tmpdir = safe_strdup (g, dir_template); + if (mkdtemp (g->tmpdir) == NULL) { + perrorf (g, _("%s: cannot create temporary directory"), dir_template); + goto cleanup0; + } + } + + /* First search g->path for the supermin appliance, and try to + * synthesize a kernel and initrd from that. If it fails, we + * try the path search again looking for a backup ordinary + * appliance. + */ pelem = path = safe_strdup (g, g->path); do { pend = strchrnul (pelem, ':'); @@ -740,32 +798,31 @@ guestfs_launch (guestfs_h *g) *pend = '\0'; len = pend - pelem; - /* Empty element or "." means cwd. */ + /* Empty element of "." means cwd. */ if (len == 0 || (len == 1 && *pelem == '.')) { if (g->verbose) fprintf (stderr, - "looking for kernel and initrd in current directory\n"); - if (access (kernel_name, F_OK) == 0 && access (initrd_name, F_OK) == 0) { - kernel = safe_strdup (g, kernel_name); - initrd = safe_strdup (g, initrd_name); + "looking for supermin appliance in current directory\n"); + if (dir_contains_files (".", + supermin_name, supermin_hostfiles_name, + "kmod.whitelist", NULL)) { + if (build_supermin_appliance (g, ".", &kernel, &initrd) == -1) + return -1; break; } } - /* Look at /kernel etc. */ + /* Look at /supermin* etc. */ else { - kernel = safe_malloc (g, len + strlen (kernel_name) + 2); - initrd = safe_malloc (g, len + strlen (initrd_name) + 2); - sprintf (kernel, "%s/%s", pelem, kernel_name); - sprintf (initrd, "%s/%s", pelem, initrd_name); - if (g->verbose) - fprintf (stderr, "looking for %s and %s\n", kernel, initrd); + fprintf (stderr, "looking for supermin appliance in %s\n", pelem); - if (access (kernel, F_OK) == 0 && access (initrd, F_OK) == 0) + if (dir_contains_files (pelem, + supermin_name, supermin_hostfiles_name, + "kmod.whitelist", NULL)) { + if (build_supermin_appliance (g, pelem, &kernel, &initrd) == -1) + return -1; break; - free (kernel); - free (initrd); - kernel = initrd = NULL; + } } pelem = pend + 1; @@ -774,6 +831,46 @@ guestfs_launch (guestfs_h *g) free (path); if (kernel == NULL || initrd == NULL) { + /* Search g->path for the kernel and initrd. */ + pelem = path = safe_strdup (g, g->path); + do { + pend = strchrnul (pelem, ':'); + pmore = *pend == ':'; + *pend = '\0'; + len = pend - pelem; + + /* Empty element or "." means cwd. */ + if (len == 0 || (len == 1 && *pelem == '.')) { + if (g->verbose) + fprintf (stderr, + "looking for appliance in current directory\n"); + if (dir_contains_files (".", kernel_name, initrd_name, NULL)) { + kernel = safe_strdup (g, kernel_name); + initrd = safe_strdup (g, initrd_name); + break; + } + } + /* Look at /kernel etc. */ + else { + if (g->verbose) + fprintf (stderr, "looking for appliance in %s\n", pelem); + + if (dir_contains_files (pelem, kernel_name, initrd_name, NULL)) { + kernel = safe_malloc (g, len + strlen (kernel_name) + 2); + initrd = safe_malloc (g, len + strlen (initrd_name) + 2); + sprintf (kernel, "%s/%s", pelem, kernel_name); + sprintf (initrd, "%s/%s", pelem, initrd_name); + break; + } + } + + pelem = pend + 1; + } while (pmore); + + free (path); + } + + if (kernel == NULL || initrd == NULL) { error (g, _("cannot find %s or %s on LIBGUESTFS_PATH (current path = %s)"), kernel_name, initrd_name, g->path); goto cleanup0; @@ -788,15 +885,7 @@ guestfs_launch (guestfs_h *g) */ memsize = 384; - /* Make the temporary directory containing the socket. */ - if (!g->tmpdir) { - g->tmpdir = safe_strdup (g, dir_template); - if (mkdtemp (g->tmpdir) == NULL) { - perrorf (g, _("%s: cannot create temporary directory"), dir_template); - goto cleanup0; - } - } - + /* Make the vmchannel socket. */ snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir); unlink (unixsock); @@ -1048,6 +1137,34 @@ guestfs_launch (guestfs_h *g) return -1; } +/* This function does the hard work of building the supermin appliance + * on the fly. 'path' is the directory containing the control files. + * 'kernel' and 'initrd' are where we will return the names of the + * kernel and initrd (only initrd is built). The work is done by + * an external script. We just tell it where to put the result. + */ +static int +build_supermin_appliance (guestfs_h *g, const char *path, + char **kernel, char **initrd) +{ + char cmd[4096]; + int r; + + snprintf (cmd, sizeof cmd, + "PATH='%s':$PATH " + "guestfs-supermin-helper '%s' %s/kernel %s/initrd", + path, + path, g->tmpdir, g->tmpdir); + + r = system (cmd); + if (r == -1 || WEXITSTATUS(r) != 0) { + error (g, _("external command failed: %s"), cmd); + return -1; + } + + return 0; +} + static void finish_wait_ready (guestfs_h *g, void *vp) {