aboutsummaryrefslogtreecommitdiffstats
path: root/tools/genext2fs
diff options
context:
space:
mode:
authorJohn Crispin <john@openwrt.org>2014-06-02 12:43:46 +0000
committerJohn Crispin <john@openwrt.org>2014-06-02 12:43:46 +0000
commitb6fbe7bd5da6548323030ced25582d90c7a99cc7 (patch)
tree3b6bfae0ed3612370256faadda43848af26c85c8 /tools/genext2fs
parent7ba5188fe94b667cc17aeb010626c5d245a92aca (diff)
downloadupstream-b6fbe7bd5da6548323030ced25582d90c7a99cc7.tar.gz
upstream-b6fbe7bd5da6548323030ced25582d90c7a99cc7.tar.bz2
upstream-b6fbe7bd5da6548323030ced25582d90c7a99cc7.zip
tools: genext2fs: add support for blocksize != 1024
This patch series is extracted from http://ftp.de.debian.org/debian/pool/main/g/genext2fs/genext2fs_1.4.1-4.debian.tar.gz The patches are used in Debian for quite a long time, so I assume that this is solid material. At least, my Ubuntu host fsck.ext4 does not bark :-) The goal is to allow building filesystems with larger blocksizes instead of the current default of 1k. This should improve performance and lifetime when the filesystem is stored e.g. on a SD card (on Raspberry Pi/I2SE Duckbill for example) which uses internal flash memory. Writing to flash memory is slow because writing the data of one block results in erasing a whole erase block of the flash memory. Thus it is preferable to align the filesystem block size on a flash device with the erase blocksize, or at least bring it closer to the later one, to avoid unnecessary write amplification. Signed-off-by: Michael Heimpold <mhei@heimpold.de> SVN-Revision: 40921
Diffstat (limited to 'tools/genext2fs')
-rw-r--r--tools/genext2fs/patches/100-c99_scanf.patch21
-rw-r--r--tools/genext2fs/patches/200-autoconf.patch13
-rw-r--r--tools/genext2fs/patches/300-blocksize-creator.patch558
-rw-r--r--tools/genext2fs/patches/400-byteswap_fix.patch44
4 files changed, 636 insertions, 0 deletions
diff --git a/tools/genext2fs/patches/100-c99_scanf.patch b/tools/genext2fs/patches/100-c99_scanf.patch
new file mode 100644
index 0000000000..e7aa17cc6f
--- /dev/null
+++ b/tools/genext2fs/patches/100-c99_scanf.patch
@@ -0,0 +1,21 @@
+commit 3b8ca0ce9a0b58287a780747c90c449bdebfe464
+Author: Xavier Bestel <bestouff@users.sourceforge.net>
+Date: Mon Jan 14 08:52:44 2008 +0000
+
+ removed use of %as is scanf (GNU conflicts with C99) by Giacomo Catenazzi <cate@debian.org>
+
+diff --git a/genext2fs.c b/genext2fs.c
+index 070b270..f0d797d 100644
+--- a/genext2fs.c
++++ b/genext2fs.c
+@@ -286,7 +286,9 @@ typedef unsigned int uint32;
+ // older solaris. Note that this is still not very portable, in that
+ // the return value cannot be trusted.
+
+-#if SCANF_CAN_MALLOC
++#if 0 // SCANF_CAN_MALLOC
++// C99 define "a" for floating point, so you can have runtime surprise
++// according the library versions
+ # define SCANF_PREFIX "a"
+ # define SCANF_STRING(s) (&s)
+ #else
diff --git a/tools/genext2fs/patches/200-autoconf.patch b/tools/genext2fs/patches/200-autoconf.patch
new file mode 100644
index 0000000000..b3317bdd10
--- /dev/null
+++ b/tools/genext2fs/patches/200-autoconf.patch
@@ -0,0 +1,13 @@
+Index: genext2fs/m4/ac_func_scanf_can_malloc.m4
+===================================================================
+--- genext2fs.orig/m4/ac_func_scanf_can_malloc.m4 2011-09-03 21:28:49.000000000 +0200
++++ genext2fs/m4/ac_func_scanf_can_malloc.m4 2011-09-03 21:29:41.000000000 +0200
+@@ -9,7 +9,7 @@
+ # --------------------------------------
+ AC_DEFUN([AC_FUNC_SCANF_CAN_MALLOC],
+ [ AC_CHECK_HEADERS([stdlib.h])
+- AC_CACHE_CHECK([whether scanf can malloc], [ac_scanf_can_malloc],
++ AC_CACHE_CHECK([whether scanf can malloc], [ac_cv_func_scanf_can_malloc],
+ [ AC_RUN_IFELSE(
+ [ AC_LANG_PROGRAM(
+ [
diff --git a/tools/genext2fs/patches/300-blocksize-creator.patch b/tools/genext2fs/patches/300-blocksize-creator.patch
new file mode 100644
index 0000000000..97a4836eeb
--- /dev/null
+++ b/tools/genext2fs/patches/300-blocksize-creator.patch
@@ -0,0 +1,558 @@
+Index: genext2fs/genext2fs.c
+===================================================================
+--- genext2fs.orig/genext2fs.c 2011-09-03 14:21:17.000000000 +0200
++++ genext2fs/genext2fs.c 2011-09-03 14:21:17.000000000 +0200
+@@ -151,13 +151,24 @@
+
+ // block size
+
+-#define BLOCKSIZE 1024
++static int blocksize = 1024;
++
++#define BLOCKSIZE blocksize
+ #define BLOCKS_PER_GROUP 8192
+ #define INODES_PER_GROUP 8192
+ /* Percentage of blocks that are reserved.*/
+ #define RESERVED_BLOCKS 5/100
+ #define MAX_RESERVED_BLOCKS 25/100
+
++/* The default value for s_creator_os. */
++#if defined(__GNU__)
++# define CREATOR_OS 1 /* Hurd */
++#elif defined(__FreeBSD__)
++# define CREATOR_OS 3 /* FreeBSD */
++#else
++# define CREATOR_OS 0 /* Linux */
++#endif
++
+
+ // inode block size (why is it != BLOCKSIZE ?!?)
+ /* The field i_blocks in the ext2 inode stores the number of data blocks
+@@ -239,10 +250,10 @@
+ (fs)->sb.s_blocks_per_group - 1) / (fs)->sb.s_blocks_per_group)
+
+ // Get group block bitmap (bbm) given the group number
+-#define GRP_GET_GROUP_BBM(fs,grp) ( get_blk((fs),(fs)->gd[(grp)].bg_block_bitmap) )
++#define GRP_GET_GROUP_BBM(fs,grp) ( get_blk((fs), get_gd((fs),(grp))->bg_block_bitmap) )
+
+ // Get group inode bitmap (ibm) given the group number
+-#define GRP_GET_GROUP_IBM(fs,grp) ( get_blk((fs),(fs)->gd[(grp)].bg_inode_bitmap) )
++#define GRP_GET_GROUP_IBM(fs,grp) ( get_blk((fs), get_gd((fs),(grp))->bg_inode_bitmap) )
+
+ // Given an inode number find the group it belongs to
+ #define GRP_GROUP_OF_INODE(fs,nod) ( ((nod)-1) / (fs)->sb.s_inodes_per_group)
+@@ -532,7 +543,7 @@
+ char d_name[0];
+ } directory;
+
+-typedef uint8 block[BLOCKSIZE];
++typedef uint8 *block;
+
+ /* blockwalker fields:
+ The blockwalker is used to access all the blocks of a file (including
+@@ -571,16 +582,12 @@
+
+
+ /* Filesystem structure that support groups */
+-#if BLOCKSIZE == 1024
+ typedef struct
+ {
+- block zero; // The famous block 0
+- superblock sb; // The superblock
+- groupdescriptor gd[0]; // The group descriptors
++ uint8 zero[1024]; // Room for bootloader stuff
++ superblock sb; // The superblock, always at 1024
++ // group descriptors come next, see get_gd() below
+ } filesystem;
+-#else
+-#error UNHANDLED BLOCKSIZE
+-#endif
+
+ // now the endianness swap
+
+@@ -820,6 +827,14 @@
+ return (uint8*)fs + blk*BLOCKSIZE;
+ }
+
++// the group descriptors are aligned on the block size
++static inline groupdescriptor *
++get_gd(filesystem *fs, int no)
++{
++ int gdblk = (sizeof (filesystem) + BLOCKSIZE - 1) / BLOCKSIZE;
++ return ((groupdescriptor *) get_blk(fs, gdblk)) + no;
++}
++
+ // return a given inode from a filesystem
+ static inline inode *
+ get_nod(filesystem *fs, uint32 nod)
+@@ -829,7 +844,7 @@
+
+ offset = GRP_IBM_OFFSET(fs,nod);
+ grp = GRP_GROUP_OF_INODE(fs,nod);
+- itab = (inode *)get_blk(fs, fs->gd[grp].bg_inode_table);
++ itab = (inode *)get_blk(fs, get_gd(fs,grp)->bg_inode_table);
+ return itab+offset-1;
+ }
+
+@@ -875,18 +890,18 @@
+
+ grp = GRP_GROUP_OF_INODE(fs,nod);
+ nbgroups = GRP_NBGROUPS(fs);
+- if(!(bk = allocate(get_blk(fs,fs->gd[grp].bg_block_bitmap), 0))) {
++ if(!(bk = allocate(GRP_GET_GROUP_BBM(fs, grp), 0))) {
+ for(grp=0;grp<nbgroups && !bk;grp++)
+- bk=allocate(get_blk(fs,fs->gd[grp].bg_block_bitmap),0);
++ bk = allocate(GRP_GET_GROUP_BBM(fs, grp), 0);
+ grp--;
+ }
+ if (!bk)
+ error_msg_and_die("couldn't allocate a block (no free space)");
+- if(!(fs->gd[grp].bg_free_blocks_count--))
++ if(!(get_gd(fs, grp)->bg_free_blocks_count--))
+ error_msg_and_die("group descr %d. free blocks count == 0 (corrupted fs?)",grp);
+ if(!(fs->sb.s_free_blocks_count--))
+ error_msg_and_die("superblock free blocks count == 0 (corrupted fs?)");
+- return fs->sb.s_blocks_per_group*grp + bk;
++ return fs->sb.s_first_data_block + fs->sb.s_blocks_per_group*grp + (bk-1);
+ }
+
+ // free a block
+@@ -897,8 +912,8 @@
+
+ grp = bk / fs->sb.s_blocks_per_group;
+ bk %= fs->sb.s_blocks_per_group;
+- deallocate(get_blk(fs,fs->gd[grp].bg_block_bitmap), bk);
+- fs->gd[grp].bg_free_blocks_count++;
++ deallocate(GRP_GET_GROUP_BBM(fs, grp), bk);
++ get_gd(fs, grp)->bg_free_blocks_count++;
+ fs->sb.s_free_blocks_count++;
+ }
+
+@@ -918,16 +933,16 @@
+ /* We do it for all inodes. */
+ avefreei = fs->sb.s_free_inodes_count / nbgroups;
+ for(grp=0; grp<nbgroups; grp++) {
+- if (fs->gd[grp].bg_free_inodes_count < avefreei ||
+- fs->gd[grp].bg_free_inodes_count == 0)
++ if (get_gd(fs, grp)->bg_free_inodes_count < avefreei ||
++ get_gd(fs, grp)->bg_free_inodes_count == 0)
+ continue;
+ if (!best_group ||
+- fs->gd[grp].bg_free_blocks_count > fs->gd[best_group].bg_free_blocks_count)
++ get_gd(fs, grp)->bg_free_blocks_count > get_gd(fs, best_group)->bg_free_blocks_count)
+ best_group = grp;
+ }
+- if (!(nod = allocate(get_blk(fs,fs->gd[best_group].bg_inode_bitmap),0)))
++ if (!(nod = allocate(GRP_GET_GROUP_IBM(fs, best_group), 0)))
+ error_msg_and_die("couldn't allocate an inode (no free inode)");
+- if(!(fs->gd[best_group].bg_free_inodes_count--))
++ if(!(get_gd(fs, best_group)->bg_free_inodes_count--))
+ error_msg_and_die("group descr. free blocks count == 0 (corrupted fs?)");
+ if(!(fs->sb.s_free_inodes_count--))
+ error_msg_and_die("superblock free blocks count == 0 (corrupted fs?)");
+@@ -1390,7 +1405,7 @@
+ case FM_IFDIR:
+ add2dir(fs, nod, nod, ".");
+ add2dir(fs, nod, parent_nod, "..");
+- fs->gd[GRP_GROUP_OF_INODE(fs,nod)].bg_used_dirs_count++;
++ get_gd(fs, GRP_GROUP_OF_INODE(fs,nod))->bg_used_dirs_count++;
+ break;
+ }
+ }
+@@ -1860,7 +1875,7 @@
+ swap_nod(nod);
+ }
+ for(i=0;i<GRP_NBGROUPS(fs);i++)
+- swap_gd(&(fs->gd[i]));
++ swap_gd(get_gd(fs, i));
+ swap_sb(&fs->sb);
+ }
+
+@@ -1870,7 +1885,7 @@
+ uint32 i;
+ swap_sb(&fs->sb);
+ for(i=0;i<GRP_NBGROUPS(fs);i++)
+- swap_gd(&(fs->gd[i]));
++ swap_gd(get_gd(fs, i));
+ for(i = 1; i < fs->sb.s_inodes_count; i++)
+ {
+ inode *nod = get_nod(fs, i);
+@@ -1895,7 +1910,8 @@
+
+ // initialize an empty filesystem
+ static filesystem *
+-init_fs(int nbblocks, int nbinodes, int nbresrvd, int holes, uint32 fs_timestamp)
++init_fs(int nbblocks, int nbinodes, int nbresrvd, int holes,
++ uint32 fs_timestamp, uint32 creator_os)
+ {
+ uint32 i;
+ filesystem *fs;
+@@ -1921,10 +1937,14 @@
+ */
+ min_nbgroups = (nbinodes + INODES_PER_GROUP - 1) / INODES_PER_GROUP;
+
++ /* On filesystems with 1k block size, the bootloader area uses a full
++ * block. For 2048 and up, the superblock can be fitted into block 0.
++ */
++ first_block = (BLOCKSIZE == 1024);
++
+ /* nbblocks is the total number of blocks in the filesystem.
+ * a block group can have no more than 8192 blocks.
+ */
+- first_block = (BLOCKSIZE == 1024);
+ nbgroups = (nbblocks - first_block + BLOCKS_PER_GROUP - 1) / BLOCKS_PER_GROUP;
+ if(nbgroups < min_nbgroups) nbgroups = min_nbgroups;
+ nbblocks_per_group = rndup((nbblocks - first_block + nbgroups - 1)/nbgroups, 8);
+@@ -1936,10 +1956,10 @@
+ gdsz = rndup(nbgroups*sizeof(groupdescriptor),BLOCKSIZE)/BLOCKSIZE;
+ itblsz = nbinodes_per_group * sizeof(inode)/BLOCKSIZE;
+ overhead_per_group = 3 /*sb,bbm,ibm*/ + gdsz + itblsz;
+- if((uint32)nbblocks - 1 < overhead_per_group * nbgroups)
+- error_msg_and_die("too much overhead, try fewer inodes or more blocks. Note: options have changed, see --help or the man page.");
+- free_blocks = nbblocks - overhead_per_group*nbgroups - 1 /*boot block*/;
++ free_blocks = nbblocks - overhead_per_group*nbgroups - first_block;
+ free_blocks_per_group = nbblocks_per_group - overhead_per_group;
++ if(free_blocks < 0)
++ error_msg_and_die("too much overhead, try fewer inodes or more blocks. Note: options have changed, see --help or the man page.");
+
+ if(!(fs = (filesystem*)calloc(nbblocks, BLOCKSIZE)))
+ error_msg_and_die("not enough memory for filesystem");
+@@ -1959,28 +1979,31 @@
+ fs->sb.s_wtime = fs_timestamp;
+ fs->sb.s_magic = EXT2_MAGIC_NUMBER;
+ fs->sb.s_lastcheck = fs_timestamp;
++ fs->sb.s_creator_os = creator_os;
+
+ // set up groupdescriptors
+- for(i=0, bbmpos=gdsz+2, ibmpos=bbmpos+1, itblpos=ibmpos+1;
++ for(i=0, bbmpos=first_block+1+gdsz, ibmpos=bbmpos+1, itblpos=ibmpos+1;
+ i<nbgroups;
+ i++, bbmpos+=nbblocks_per_group, ibmpos+=nbblocks_per_group, itblpos+=nbblocks_per_group)
+ {
++ groupdescriptor *gd = get_gd(fs, i);
++
+ if(free_blocks > free_blocks_per_group) {
+- fs->gd[i].bg_free_blocks_count = free_blocks_per_group;
++ gd->bg_free_blocks_count = free_blocks_per_group;
+ free_blocks -= free_blocks_per_group;
+ } else {
+- fs->gd[i].bg_free_blocks_count = free_blocks;
++ gd->bg_free_blocks_count = free_blocks;
+ free_blocks = 0; // this is the last block group
+ }
+ if(i)
+- fs->gd[i].bg_free_inodes_count = nbinodes_per_group;
++ gd->bg_free_inodes_count = nbinodes_per_group;
+ else
+- fs->gd[i].bg_free_inodes_count = nbinodes_per_group -
++ gd->bg_free_inodes_count = nbinodes_per_group -
+ EXT2_FIRST_INO + 2;
+- fs->gd[i].bg_used_dirs_count = 0;
+- fs->gd[i].bg_block_bitmap = bbmpos;
+- fs->gd[i].bg_inode_bitmap = ibmpos;
+- fs->gd[i].bg_inode_table = itblpos;
++ gd->bg_used_dirs_count = 0;
++ gd->bg_block_bitmap = bbmpos;
++ gd->bg_inode_bitmap = ibmpos;
++ gd->bg_inode_table = itblpos;
+ }
+
+ /* Mark non-filesystem blocks and inodes as allocated */
+@@ -1988,9 +2011,9 @@
+ for(i = 0; i<nbgroups;i++) {
+
+ /* Block bitmap */
+- bbm = get_blk(fs,fs->gd[i].bg_block_bitmap);
++ bbm = GRP_GET_GROUP_BBM(fs, i);
+ //non-filesystem blocks
+- for(j = fs->gd[i].bg_free_blocks_count
++ for(j = get_gd(fs, i)->bg_free_blocks_count
+ + overhead_per_group + 1; j <= BLOCKSIZE * 8; j++)
+ allocate(bbm, j);
+ //system blocks
+@@ -1998,7 +2021,7 @@
+ allocate(bbm, j);
+
+ /* Inode bitmap */
+- ibm = get_blk(fs,fs->gd[i].bg_inode_bitmap);
++ ibm = GRP_GET_GROUP_IBM(fs, i);
+ //non-filesystem inodes
+ for(j = fs->sb.s_inodes_per_group+1; j <= BLOCKSIZE * 8; j++)
+ allocate(ibm, j);
+@@ -2012,9 +2035,9 @@
+ // make root inode and directory
+ /* We have groups now. Add the root filesystem in group 0 */
+ /* Also increment the directory count for group 0 */
+- fs->gd[0].bg_free_inodes_count--;
+- fs->gd[0].bg_used_dirs_count = 1;
+- itab0 = (inode *)get_blk(fs,fs->gd[0].bg_inode_table);
++ get_gd(fs, 0)->bg_free_inodes_count--;
++ get_gd(fs, 0)->bg_used_dirs_count = 1;
++ itab0 = (inode *)get_blk(fs, get_gd(fs,0)->bg_inode_table);
+ itab0[EXT2_ROOT_INO-1].i_mode = FM_IFDIR | FM_IRWXU | FM_IRGRP | FM_IROTH | FM_IXGRP | FM_IXOTH;
+ itab0[EXT2_ROOT_INO-1].i_ctime = fs_timestamp;
+ itab0[EXT2_ROOT_INO-1].i_mtime = fs_timestamp;
+@@ -2338,8 +2361,9 @@
+ for (i = 0; i < GRP_NBGROUPS(fs); i++) {
+ printf("Group No: %d\n", i+1);
+ printf("block bitmap: block %d,inode bitmap: block %d, inode table: block %d\n",
+- fs->gd[i].bg_block_bitmap, fs->gd[i].bg_inode_bitmap,
+- fs->gd[i].bg_inode_table);
++ get_gd(fs, i)->bg_block_bitmap,
++ get_gd(fs, i)->bg_inode_bitmap,
++ get_gd(fs, i)->bg_inode_table);
+ printf("block bitmap allocation:\n");
+ print_bm(GRP_GET_GROUP_BBM(fs, i),fs->sb.s_blocks_per_group);
+ printf("inode bitmap allocation:\n");
+@@ -2421,10 +2445,12 @@
+ " -x, --starting-image <image>\n"
+ " -d, --root <directory>\n"
+ " -D, --devtable <file>\n"
++ " -B, --block-size <bytes>\n"
+ " -b, --size-in-blocks <blocks>\n"
+ " -i, --bytes-per-inode <bytes per inode>\n"
+ " -N, --number-of-inodes <number of inodes>\n"
+ " -m, --reserved-percentage <percentage of blocks to reserve>\n"
++ " -o, --creator-os <os> 'linux', 'hurd', 'freebsd' or a numerical value.\n"
+ " -g, --block-map <path> Generate a block map file for this path.\n"
+ " -e, --fill-value <value> Fill unallocated blocks with value.\n"
+ " -z, --allow-holes Allow files with holes.\n"
+@@ -2446,6 +2472,29 @@
+ extern char* optarg;
+ extern int optind, opterr, optopt;
+
++// parse the value for -o <os>
++int
++lookup_creator_os(const char *name)
++{
++ static const char *const creators[] =
++ {"linux", "hurd", "2", "freebsd", NULL};
++ char *endptr;
++ int i;
++
++ // numerical value ?
++ i = strtol(name, &endptr, 0);
++ if(name[0] && *endptr == '\0')
++ return i;
++
++ // symbolic name ?
++ for(i=0; creators[i]; i++)
++ if(strcasecmp(creators[i], name) == 0)
++ return i;
++
++ // whatever ?
++ return -1;
++}
++
+ int
+ main(int argc, char **argv)
+ {
+@@ -2455,6 +2504,7 @@
+ float bytes_per_inode = -1;
+ float reserved_frac = -1;
+ int fs_timestamp = -1;
++ int creator_os = CREATOR_OS;
+ char * fsout = "-";
+ char * fsin = 0;
+ char * dopt[MAX_DOPT];
+@@ -2478,10 +2528,12 @@
+ { "starting-image", required_argument, NULL, 'x' },
+ { "root", required_argument, NULL, 'd' },
+ { "devtable", required_argument, NULL, 'D' },
++ { "block-size", required_argument, NULL, 'B' },
+ { "size-in-blocks", required_argument, NULL, 'b' },
+ { "bytes-per-inode", required_argument, NULL, 'i' },
+ { "number-of-inodes", required_argument, NULL, 'N' },
+ { "reserved-percentage", required_argument, NULL, 'm' },
++ { "creator-os", required_argument, NULL, 'o' },
+ { "block-map", required_argument, NULL, 'g' },
+ { "fill-value", required_argument, NULL, 'e' },
+ { "allow-holes", no_argument, NULL, 'z' },
+@@ -2497,11 +2549,11 @@
+
+ app_name = argv[0];
+
+- while((c = getopt_long(argc, argv, "x:d:D:b:i:N:m:g:e:zfqUPhVv", longopts, NULL)) != EOF) {
++ while((c = getopt_long(argc, argv, "x:d:D:B:b:i:N:m:o:g:e:zfqUPhVv", longopts, NULL)) != EOF) {
+ #else
+ app_name = argv[0];
+
+- while((c = getopt(argc, argv, "x:d:D:b:i:N:m:g:e:zfqUPhVv")) != EOF) {
++ while((c = getopt(argc, argv, "x:d:D:B:b:i:N:m:o:g:e:zfqUPhVv")) != EOF) {
+ #endif /* HAVE_GETOPT_LONG */
+ switch(c)
+ {
+@@ -2512,6 +2564,9 @@
+ case 'D':
+ dopt[didx++] = optarg;
+ break;
++ case 'B':
++ blocksize = SI_atof(optarg);
++ break;
+ case 'b':
+ nbblocks = SI_atof(optarg);
+ break;
+@@ -2524,6 +2579,9 @@
+ case 'm':
+ reserved_frac = SI_atof(optarg) / 100;
+ break;
++ case 'o':
++ creator_os = lookup_creator_os(optarg);
++ break;
+ case 'g':
+ gopt[gidx++] = optarg;
+ break;
+@@ -2567,6 +2625,11 @@
+ error_msg_and_die("Not enough arguments. Try --help or else see the man page.");
+ fsout = argv[optind];
+
++ if(blocksize != 1024 && blocksize != 2048 && blocksize != 4096)
++ error_msg_and_die("Valid block sizes: 1024, 2048 or 4096.");
++ if(creator_os < 0)
++ error_msg_and_die("Creator OS unknown.");
++
+ hdlinks.hdl = (struct hdlink_s *)malloc(hdlink_cnt * sizeof(struct hdlink_s));
+ if (!hdlinks.hdl)
+ error_msg_and_die("Not enough memory");
+@@ -2611,7 +2674,8 @@
+ }
+ if(fs_timestamp == -1)
+ fs_timestamp = time(NULL);
+- fs = init_fs(nbblocks, nbinodes, nbresrvd, holes, fs_timestamp);
++ fs = init_fs(nbblocks, nbinodes, nbresrvd, holes,
++ fs_timestamp, creator_os);
+ }
+
+ populate_fs(fs, dopt, didx, squash_uids, squash_perms, fs_timestamp, NULL);
+Index: genext2fs/test-gen.lib
+===================================================================
+--- genext2fs.orig/test-gen.lib 2011-09-03 13:40:35.000000000 +0200
++++ genext2fs/test-gen.lib 2011-09-03 14:21:17.000000000 +0200
+@@ -8,7 +8,7 @@
+ # Creates an image with a file of given size
+ # Usage: dgen file-size number-of-blocks
+ dgen () {
+- size=$1; blocks=$2
++ size=$1; blocks=$2; blocksz=$3;
+ rm -rf test
+ mkdir -p test
+ cd test
+@@ -20,7 +20,7 @@
+ chmod 777 file.$1
+ TZ=UTC-11 touch -t 200502070321.43 file.$1 .
+ cd ..
+- ./genext2fs -N 17 -b $blocks -d test -f -q ext2.img
++ ./genext2fs -B $blocksz -N 17 -b $blocks -d test -f -o Linux -q ext2.img
+ }
+
+ # fgen - Exercises the -f spec-file option of genext2fs
+@@ -31,7 +31,7 @@
+ mkdir -p test
+ cp $fname test
+ TZ=UTC-11 touch -t 200502070321.43 test/$fname
+- ./genext2fs -N 92 -b $blocks -D test/$fname -f ext2.img
++ ./genext2fs -N 92 -b $blocks -D test/$fname -f -o Linux ext2.img
+ }
+
+ # gen_cleanup - Remove the files generated by the above functions
+Index: genext2fs/test-mount.sh
+===================================================================
+--- genext2fs.orig/test-mount.sh 2011-09-03 13:40:35.000000000 +0200
++++ genext2fs/test-mount.sh 2011-09-03 14:21:17.000000000 +0200
+@@ -33,9 +33,9 @@
+ # and returns the command line with which to invoke dtest()
+ # Usage: dtest-mount file-size number-of-blocks
+ dtest_mount () {
+- size=$1; blocks=$2
+- echo Testing with file of size $size
+- dgen $size $blocks
++ size=$1; blocks=$2; blocksz=$3;
++ echo Testing $blocks blocks of $blocksz bytes with file of size $size
++ dgen $size $blocks $blocksz
+ /sbin/e2fsck -fn ext2.img || fail
+ mkdir -p mnt
+ mount -t ext2 -o ro,loop ext2.img mnt || fail
+@@ -44,7 +44,7 @@
+ awk '{print $5}'`" ] ; then
+ fail
+ fi
+- pass dtest $size $blocks
++ pass dtest $size $blocks $blocksz
+ }
+
+ # ftest-mount - Exercise the -f spec-file option of genext2fs
+@@ -75,13 +75,21 @@
+ pass ftest $fname $blocks
+ }
+
+-dtest_mount 0 4096
+-dtest_mount 0 8193
+-dtest_mount 0 8194
+-dtest_mount 1 4096
+-dtest_mount 12288 4096
+-dtest_mount 274432 4096
+-dtest_mount 8388608 9000
+-dtest_mount 16777216 20000
++dtest_mount 0 4096 1024
++dtest_mount 0 2048 2048
++dtest_mount 0 1024 4096
++dtest_mount 0 8193 1024
++dtest_mount 0 8194 1024
++dtest_mount 0 8193 4096
++dtest_mount 0 8194 2048
++dtest_mount 1 4096 1024
++dtest_mount 1 1024 4096
++dtest_mount 12288 4096 1024
++dtest_mount 274432 4096 1024
++dtest_mount 8388608 9000 1024
++dtest_mount 8388608 4500 2048
++dtest_mount 8388608 2250 4096
++dtest_mount 16777216 20000 1024
++dtest_mount 16777216 10000 2048
+
+ ftest_mount device_table.txt 4096
+Index: genext2fs/test.sh
+===================================================================
+--- genext2fs.orig/test.sh 2011-09-03 13:40:35.000000000 +0200
++++ genext2fs/test.sh 2011-09-03 14:21:17.000000000 +0200
+@@ -30,9 +30,9 @@
+ # Creates an image with a file of given size and verifies it
+ # Usage: dtest file-size number-of-blocks correct-checksum
+ dtest () {
+- size=$1; blocks=$2; checksum=$3
++ size=$1; blocks=$2; blocksz=$3; checksum=$4
+ echo Testing with file of size $size
+- dgen $size $blocks
++ dgen $size $blocks $blocksz
+ md5cmp $checksum
+ gen_cleanup
+ }
+@@ -53,12 +53,20 @@
+ # replace the following lines with the output of
+ # sudo sh test-mount.sh|grep test
+
+-dtest 0 4096 3bc6424b8fcd51a0de34ee59d91d5f16
+-dtest 0 8193 f174804f6b433b552706cbbfc60c416d
+-dtest 0 8194 4855a55d0cbdc44584634df49ebd5711
+-dtest 1 4096 09c569b6bfb45222c729c42d04d5451f
+-dtest 12288 4096 61febcbfbf32024ef99103fcdc282c39
+-dtest 274432 4096 0c517803552c55c1806e4220b0a0164f
+-dtest 8388608 9000 e0e5ea15bced10ab486d8135584b5d8e
+-dtest 16777216 20000 fdf636eb905ab4dc1bf76dce5ac5d209
++dtest 0 4096 1024 3bc6424b8fcd51a0de34ee59d91d5f16
++dtest 0 2048 2048 230afa16496df019878cc2370c661cdc
++dtest 0 1024 4096 ebff5eeb38b70f3f1cd081e60eb44561
++dtest 0 8193 1024 f174804f6b433b552706cbbfc60c416d
++dtest 0 8194 1024 4855a55d0cbdc44584634df49ebd5711
++dtest 0 8193 4096 c493679698418ec7e6552005e2d2a6d8
++dtest 0 8194 2048 ec13f328fa7543563f35f494bddc059c
++dtest 1 4096 1024 09c569b6bfb45222c729c42d04d5451f
++dtest 1 1024 4096 d318a326fdc907810ae9e6b0a20e9b06
++dtest 12288 4096 1024 61febcbfbf32024ef99103fcdc282c39
++dtest 274432 4096 1024 0c517803552c55c1806e4220b0a0164f
++dtest 8388608 9000 1024 e0e5ea15bced10ab486d8135584b5d8e
++dtest 8388608 4500 2048 39f4d537a72f5053fd6891721c59680d
++dtest 8388608 2250 4096 1d697fa4bc2cfffe02ac91edfadc40bf
++dtest 16777216 20000 1024 fdf636eb905ab4dc1bf76dce5ac5d209
++dtest 16777216 10000 2048 f9824a81ea5e74fdf469c097927c292b
+ ftest device_table.txt 4096 a0af06d944b11d2902dfd705484c64cc
diff --git a/tools/genext2fs/patches/400-byteswap_fix.patch b/tools/genext2fs/patches/400-byteswap_fix.patch
new file mode 100644
index 0000000000..7b3c00b5ee
--- /dev/null
+++ b/tools/genext2fs/patches/400-byteswap_fix.patch
@@ -0,0 +1,44 @@
+Index: genext2fs/genext2fs.c
+===================================================================
+--- genext2fs.orig/genext2fs.c 2011-11-29 17:36:06.000000000 +0100
++++ genext2fs/genext2fs.c 2011-11-29 17:37:37.000000000 +0100
+@@ -1779,7 +1779,8 @@
+ assert(nod->i_block[EXT2_DIND_BLOCK] != 0);
+ for(i = 0; i < BLOCKSIZE/4; i++)
+ if(nblk > EXT2_IND_BLOCK + BLOCKSIZE/4 + (BLOCKSIZE/4)*i )
+- swap_block(get_blk(fs, ((uint32*)get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]))[i]));
++ if (((uint32*)get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]))[i])
++ swap_block(get_blk(fs, ((uint32*)get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]))[i]));
+ swap_block(get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]));
+ if(nblk <= EXT2_IND_BLOCK + BLOCKSIZE/4 + BLOCKSIZE/4 * BLOCKSIZE/4)
+ return;
+@@ -1792,7 +1793,8 @@
+ (BLOCKSIZE/4)*(BLOCKSIZE/4) +
+ i*(BLOCKSIZE/4)*(BLOCKSIZE/4) +
+ j*(BLOCKSIZE/4)) )
+- swap_block(get_blk(fs,b2[j]));
++ if (b2[j])
++ swap_block(get_blk(fs,b2[j]));
+ else {
+ done = 1;
+ break;
+@@ -1825,7 +1827,8 @@
+ swap_block(get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]));
+ for(i = 0; i < BLOCKSIZE/4; i++)
+ if(nblk > EXT2_IND_BLOCK + BLOCKSIZE/4 + (BLOCKSIZE/4)*i )
+- swap_block(get_blk(fs, ((uint32*)get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]))[i]));
++ if (((uint32*)get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]))[i])
++ swap_block(get_blk(fs, ((uint32*)get_blk(fs, nod->i_block[EXT2_DIND_BLOCK]))[i]));
+ if(nblk <= EXT2_IND_BLOCK + BLOCKSIZE/4 + BLOCKSIZE/4 * BLOCKSIZE/4)
+ return;
+ /* Adding support for triple indirection */
+@@ -1839,7 +1842,8 @@
+ (BLOCKSIZE/4)*(BLOCKSIZE/4) +
+ i*(BLOCKSIZE/4)*(BLOCKSIZE/4) +
+ j*(BLOCKSIZE/4)) )
+- swap_block(get_blk(fs,b2[j]));
++ if (b2[j])
++ swap_block(get_blk(fs,b2[j]));
+ else {
+ done = 1;
+ break;