Re: [Libguestfs] [PATCH 2/4] febootstrap: Cope with non-existing insmod.static

Add module loading functionality into init.c, make copying insmod.static to initrd optional. --- configure.ac | 14 +++++--------- helper/ext2initrd.c | 2 ++ helper/init.c | 37 +++++++++++++++++++++++++++++++++++++ 3 files changed, 44 insertions(+), 9 deletions(-) diff --git a/configure.ac b/configure.ac index 7606bca..382e270 100644 --- a/configure.ac +++ b/configure.ac @@ -71,17 +71,13 @@ dnl Required programs, libraries. AC_PATH_PROG([INSMODSTATIC],[insmod.static],[no], [$PATH$PATH_SEPARATOR/sbin$PATH_SEPARATOR]) if test "x$INSMODSTATIC" = "xno" ; then - AC_MSG_FAILURE([insmod.static program not found - -Is /sbin in your current path? - -Note that Debian/Ubuntu do not package this file from module-init-tools. -Sorry, please fix your distribution. In the meantime you can copy -/sbin/insmod.static from a Fedora machine. + AC_MSG_WARN([insmod.static program not found +Compiling insmod functionality directly into init program. ]) +else + AC_DEFINE_UNQUOTED([INSMODSTATIC],["$INSMODSTATIC"], + [Full path to the insmod.static program.]) fi -AC_DEFINE_UNQUOTED([INSMODSTATIC],["$INSMODSTATIC"], - [Full path to the insmod.static program.]) AC_PATH_PROG([MKE2FS],[mke2fs],[no], [$PATH$PATH_SEPARATOR/sbin$PATH_SEPARATOR]) diff --git a/helper/ext2initrd.c b/helper/ext2initrd.c index 3d765ca..c65ecf8 100644 --- a/helper/ext2initrd.c +++ b/helper/ext2initrd.c @@ -155,6 +155,7 @@ ext2_make_initrd (const char *modpath, const char *initrd) free (cmd); free_module_deps (); +#ifdef INSMODSTATIC /* Copy in insmod static binary. */ cmd = xasprintf ("cp %s %s", INSMODSTATIC, dir); if (verbose >= 2) fprintf (stderr, "%s\n", cmd); @@ -163,6 +164,7 @@ ext2_make_initrd (const char *modpath, const char *initrd) error (EXIT_FAILURE, 0, "ext2_make_initrd: copy %s failed", INSMODSTATIC); free (cmd); +#endif /* Copy in the init program, linked into this program as a data blob. */ char *init = xasprintf ("%s/init", dir); diff --git a/helper/init.c b/helper/init.c index 7b6b94e..ac71018 100644 --- a/helper/init.c +++ b/helper/init.c @@ -36,6 +36,12 @@ #include <sys/stat.h> #include <sys/wait.h> +#ifndef INSMODSTATIC +#include <fcntl.h> +#include <asm/unistd.h> +extern long init_module(void *, unsigned long, const char *); +#endif + /* Leave this enabled for now. When we get more confident in the boot * process we can turn this off or make it configurable. */ @@ -70,7 +76,9 @@ main () * executable. Just make it executable. It's easier than fixing * everyone's distro. */ +#ifdef INSMODSTATIC chmod ("/sbin/insmod.static", 0755); +#endif FILE *fp = fopen ("/modules", "r"); if (fp == NULL) { @@ -184,9 +192,38 @@ insmod (const char *filename) } if (pid == 0) { /* Child. */ +#ifdef INSMODSTATIC execl ("/insmod.static", "insmod.static", filename, NULL); perror ("insmod: execl"); _exit (EXIT_FAILURE); +#else + int fd = open (filename, O_RDONLY); + if (fd == -1) { + fprintf (stderr, "insmod: open: %s: %s\n", filename, strerror(errno)); + _exit (EXIT_FAILURE); + } + struct stat st; + if (fstat (fd, &st) == -1) { + perror ("insmod: fstat"); + _exit (EXIT_FAILURE); + } + char buf[st.st_size]; + long offset = 0; + do { + long rc = read (fd, buf + offset, st.st_size - offset); + if (rc == -1) { + perror ("insmod: read"); + _exit (EXIT_FAILURE); + } + offset += rc; + } while (offset < st.st_size); + if (init_module (buf, st.st_size, "") != 0) { + fprintf (stderr, "insmod: init_module: %s: %s\n", filename, strerror(errno)); + _exit (EXIT_FAILURE); + } + close (fd); + _exit (EXIT_SUCCESS); +#endif } /* Parent. */ --