Re: [Libguestfs] [PATCH 1/1] virt-make-fs: add '--blocksize' option support

From: Nikolay Ivanets <stenavin(a)gmail.com&gt; This patch adds '--blocksize' command line option for virt-make-fs tool. This option allows specifying disk sector size as described in 'guestfs_add_drive_opts' libguestfs API. --- make-fs/make-fs.c | 28 ++++++++++++++++++++++++++-- make-fs/test-virt-make-fs.sh | 5 ++++- make-fs/virt-make-fs.pod | 10 ++++++++++ 3 files changed, 40 insertions(+), 3 deletions(-) diff --git a/make-fs/make-fs.c b/make-fs/make-fs.c index 5d8c3a385..81d1cf90b 100644 --- a/make-fs/make-fs.c +++ b/make-fs/make-fs.c @@ -54,10 +54,12 @@ int in_virt_rescue = 0; static const char *format = "raw", *label = NULL, *partition = NULL, *size_str = NULL, *type = "ext2"; +int blocksize = 0;

enum { HELP_OPTION = CHAR_MAX + 1 }; static const char options[] = "F:s:t:Vvx"; static const struct option long_options[] = { + { "blocksize", 1, 0, 0 }, { "debug", 0, 0, 'v' }, /* for compat with Perl tool */ { "floppy", 0, 0, 0 }, { "format", 1, 0, 'F' }, @@ -87,6 +89,7 @@ usage (int status) " %s [--options] input.tar.gz output.img\n" " %s [--options] directory output.img\n" "Options:\n" + " --blocksize=512|4096 Set sector size of the output disk\n" " --floppy Make a virtual floppy disk\n" " -F|--format=raw|qcow2|.. Set output format\n" " --help Display brief help\n" @@ -146,6 +149,9 @@ main (int argc, char *argv[]) partition = "mbr"; else partition = optarg; + } else if (STREQ (long_options[option_index].name, "blocksize")) { + if (sscanf (optarg, "%d", &blocksize) != 1) + error (EXIT_FAILURE, 0, _("--blocksize option is not numeric")); } else error (EXIT_FAILURE, 0, _("unknown long option: %s (%d)"), @@ -678,11 +684,23 @@ do_make_fs (const char *input, const char *output_str) estimate, estimate / 1024, estimate / 4096); } + /* For partition alignment and extra space at the end of the disk: + * by default we create first partition at 128 sector boundary and leave the

+ * last 128 sectors at the end of the disk free. + */ + if (partition) + estimate += 2 * 128 * blocksize; + estimate += 256 * 1024; /* For superblocks &c. */ if (STRPREFIX (type, "ext") && type[3] >= '3') { - /* For ext3+, add some more for the journal. */ - estimate += 1024 * 1024; + /* For ext3+, add some more for the journal. Journal should be at least + * 1024 file system blocks. By default file system block size is 1024 bytes + * if disk sector size is 512 bytes and 4096 bytes if disk sector size is + * 4096 bytes. Note that default file system block size may be changed via + * /etc/mke2fs.conf but we cannot handle that at the moment. + */

+ estimate += 1024 * (blocksize == 512 ? 1024 : 4096); } else if (STREQ (type, "ntfs")) { @@ -697,6 +715,11 @@ do_make_fs (const char *input, const char *output_str) estimate += 256 * 1024 * 1024; } + else if (STREQ (type, "xfs")) { + /* xfs requires at least 4096 blocks. Default block size is 4096 bytes. */ + estimate += 4096 * 4096; + } + /* Add 10%, see above. */ estimate *= 1.10; @@ -718,6 +741,7 @@ do_make_fs (const char *input, const char *output_str) if (guestfs_add_drive_opts (g, output, GUESTFS_ADD_DRIVE_OPTS_FORMAT, format, + GUESTFS_ADD_DRIVE_OPTS_BLOCKSIZE, blocksize, -1) == -1) return -1; diff --git a/make-fs/test-virt-make-fs.sh b/make-fs/test-virt-make-fs.sh index 79d058b6a..01c332b1d 100755 --- a/make-fs/test-virt-make-fs.sh +++ b/make-fs/test-virt-make-fs.sh @@ -83,9 +83,12 @@ size=`random_choice` choices=("" --label=FOO) label=`random_choice` +choices=(--blocksize=512 --blocksize=4096) +blocksize=`random_choice` + if [ -n "$LIBGUESTFS_DEBUG" ]; then debug=--debug; fi -params="$type $format $partition $size $label $debug" +params="$type $format $partition $size $label $blocksize $debug" echo "test-virt-make-fs: parameters: $params" rm -f test.file test.tar output.img diff --git a/make-fs/virt-make-fs.pod b/make-fs/virt-make-fs.pod index 76ccbd120..bd4802c7c 100644 --- a/make-fs/virt-make-fs.pod +++ b/make-fs/virt-make-fs.pod @@ -122,6 +122,16 @@ or rerun virt-make-fs to build another image from scratch. Display brief help. +=item B<--blocksize=512> + +=item B<--blocksize=4096> + +This parameter sets the sector size of the output disk image. + +The default is C<512> bytes. + +See also L<guestfs(3)/guestfs_add_drive_opts>. + =item B<--floppy> Create a virtual floppy disk.