mkfs.reiser: new applet. needs much polishing

Signed-off-by: Vladimir Dronnikov <dronnikov@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 379 insertions, 0 deletions

diff --git a/util-linux/mkfs_reiser.c b/util-linux/mkfs_reiser.c
new file mode 100644
index 000000000..7f37eb845
--- /dev/null
+++ b/util-linux/mkfs_reiser.c
@@ -0,0 +1,379 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * mkfs_reiser: utility to create ReiserFS filesystem
+ *
+ * Busybox'ed (2009) by Vladimir Dronnikov <dronnikov@gmail.com>
+ *
+ * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ */
+#include "libbb.h"
+#include <linux/fs.h>
+#include "volume_id/volume_id_internal.h"
+
+char BUG_wrong_field_size(void);
+#define STORE_LE(field, value) \
+do { \
+	if (sizeof(field) == 4) \
+		field = cpu_to_le32(value); \
+	else if (sizeof(field) == 2) \
+		field = cpu_to_le16(value); \
+	else if (sizeof(field) == 1) \
+		field = (value); \
+	else \
+		BUG_wrong_field_size(); \
+} while (0)
+
+#define FETCH_LE32(field) \
+	(sizeof(field) == 4 ? cpu_to_le32(field) : BUG_wrong_field_size())
+
+struct journal_params {
+	uint32_t jp_journal_1st_block;      /* where does journal start from on its device */
+	uint32_t jp_journal_dev;            /* journal device st_rdev */
+	uint32_t jp_journal_size;           /* size of the journal on FS creation. used to make sure they don't overflow it */
+	uint32_t jp_journal_trans_max;      /* max number of blocks in a transaction.  */
+	uint32_t jp_journal_magic;          /* random value made on fs creation (this was sb_journal_block_count) */
+	uint32_t jp_journal_max_batch;      /* max number of blocks to batch into a trans */
+	uint32_t jp_journal_max_commit_age; /* in seconds, how old can an async commit be */
+	uint32_t jp_journal_max_trans_age;  /* in seconds, how old can a transaction be */
+};
+
+struct reiserfs_journal_header {
+	uint32_t jh_last_flush_trans_id;    /* id of last fully flushed transaction */
+	uint32_t jh_first_unflushed_offset; /* offset in the log of where to start replay after a crash */
+	uint32_t jh_mount_id;
+	struct journal_params jh_journal;
+	uint32_t jh_last_check_mount_id;    /* the mount id of the fs during the last reiserfsck --check. */
+};
+
+struct reiserfs_super_block {
+	uint32_t sb_block_count;            /* 0 number of block on data device */
+	uint32_t sb_free_blocks;            /* 4 free blocks count */
+	uint32_t sb_root_block;             /* 8 root of the tree */
+
+	struct journal_params sb_journal;   /* 12 */
+
+	uint16_t sb_blocksize;          /* 44 */
+	uint16_t sb_oid_maxsize;        /* 46 max size of object id array, see get_objectid() commentary */
+	uint16_t sb_oid_cursize;        /* 48 current size of object id array */
+	uint16_t sb_umount_state;       /* 50 this is set to 1 when filesystem was umounted, to 2 - when not */
+
+	char s_magic[10];               /* 52 "ReIsErFs" or "ReIsEr2Fs" or "ReIsEr3Fs" */
+	uint16_t sb_fs_state;           /* 62 it is set to used by fsck to mark which phase of rebuilding is done (used for fsck debugging) */
+	uint32_t sb_hash_function_code; /* 64 code of fuction which was/is/will be used to sort names in a directory. See codes in above */
+	uint16_t sb_tree_height;        /* 68 height of filesytem tree. Tree consisting of only one root block has 2 here */
+	uint16_t sb_bmap_nr;            /* 70 amount of bitmap blocks needed to address each block of file system */
+	uint16_t sb_version;            /* 72 this field is only reliable on filesystem with non-standard journal */
+	uint16_t sb_reserved_for_journal;  /* 74 size in blocks of journal area on main device, we need to keep after non-standard journal relocation */
+	uint32_t sb_inode_generation;   /* 76 */
+	uint32_t sb_flags;              /* 80 Right now used only by inode-attributes, if enabled */
+	unsigned char s_uuid[16];       /* 84 filesystem unique identifier */
+	unsigned char s_label[16];      /* 100 filesystem volume label */
+	uint16_t sb_mnt_count;          /* 116 */
+	uint16_t sb_max_mnt_count;      /* 118 */
+	uint32_t sb_lastcheck;          /* 120 */
+	uint32_t sb_check_interval;     /* 124 */
+/* zero filled by mkreiserfs and reiserfs_convert_objectid_map_v1() so any additions must be updated there as well. */
+	char s_unused[76];              /* 128 */
+	/* 204 */
+};
+
+/* Header of a disk block.  More precisely, header of a formatted leaf
+   or internal node, and not the header of an unformatted node. */
+struct block_head {
+	uint16_t blk2_level;        /* Level of a block in the tree. */
+	uint16_t blk2_nr_item;      /* Number of keys/items in a block. */
+	uint16_t blk2_free_space;   /* Block free space in bytes. */
+	uint16_t blk_reserved;
+	uint32_t reserved[4];
+};
+
+#define REISERFS_DISK_OFFSET_IN_BYTES (64 * 1024)
+
+#define REISERFS_3_6_SUPER_MAGIC_STRING "ReIsEr2Fs"
+#define REISERFS_FORMAT_3_6     2
+#define DEFAULT_MAX_MNT_COUNT   30                      /* 30 mounts */
+#define DEFAULT_CHECK_INTERVAL  (180 * 60 * 60 * 24)    /* 180 days */
+
+#define FS_CLEANLY_UMOUNTED     1 /* this was REISERFS_VALID_FS */
+
+#define JOURNAL_MIN_SIZE        512
+/* biggest possible single transaction, don't change for now (8/3/99) */
+#define JOURNAL_TRANS_MAX       1024
+#define JOURNAL_TRANS_MIN       256     /* need to check whether it works */
+#define JOURNAL_DEFAULT_RATIO   8       /* default journal size / max trans length */
+#define JOURNAL_MIN_RATIO       2
+/* max blocks to batch into one transaction, don't make this any bigger than 900 */
+#define JOURNAL_MAX_BATCH       900
+#define JOURNAL_MAX_COMMIT_AGE  30
+
+
+// Standard mkreiserfs 3.6.21:
+//   -b | --block-size N              size of file-system block, in bytes
+//   -j | --journal-device FILE       path to separate device to hold journal
+//   -s | --journal-size N            size of the journal in blocks
+//   -o | --journal-offset N          offset of the journal from the start of
+//                                    the separate device, in blocks
+//   -t | --transaction-max-size N    maximal size of transaction, in blocks
+//   -B | --badblocks file            store all bad blocks given in file on the fs
+//   -h | --hash rupasov|tea|r5       hash function to use by default
+//   -u | --uuid UUID                 store UUID in the superblock
+//   -l | --label LABEL               store LABEL in the superblock
+//   --format 3.5|3.6                 old 3.5 format or newer 3.6
+//   -f | --force                     specified once, make mkreiserfs the whole
+//                                    disk, not block device or mounted partition;
+//                                    specified twice, do not ask for confirmation
+//   -q | --quiet                     quiet work without messages, progress and
+//                                    questions. Useful if run in a script. For use
+//                                    by end users only.
+//   -d | --debug                     print debugging information during mkreiser
+//   -V                               print version and exit
+
+// Options not commented below are taken but silently ignored:
+enum {
+	OPT_b = 1 << 0,
+	OPT_j = 1 << 1,
+	OPT_s = 1 << 2,
+	OPT_o = 1 << 3,
+	OPT_t = 1 << 4,
+	OPT_B = 1 << 5,
+	OPT_h = 1 << 6,
+	OPT_u = 1 << 7,
+	OPT_l = 1 << 8,		// label
+	OPT_f = 1 << 9,		// ask no questions
+	OPT_q = 1 << 10,
+	OPT_d = 1 << 11,
+	//OPT_V = 1 << 12,	// -V version. bbox applets don't support that
+};
+
+int mkfs_reiser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int mkfs_reiser_main(int argc UNUSED_PARAM, char **argv)
+{
+	unsigned blocksize = 4096;
+	unsigned journal_blocks = 8192;
+	unsigned blocks, bitmap_blocks, i, block;
+	time_t timestamp;
+	const char *label = "";
+	struct stat st;
+	int fd;
+	uint8_t *buf;
+	struct reiserfs_super_block *sb;
+	struct journal_params *jp;
+	struct block_head *root;
+
+	// using global "option_mask32" instead of local "opts":
+	// we are register starved here
+	opt_complementary = "-1:b+";
+	/*opts =*/ getopt32(argv, "b:j:s:o:t:B:h:u:l:fqd",
+		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &label);
+	argv += optind; // argv[0] -- device
+
+	// check the device is a block device
+	fd = xopen(argv[0], O_WRONLY | O_EXCL);
+	fstat(fd, &st);
+	if (!S_ISBLK(st.st_mode) && !(option_mask32 & OPT_f))
+		bb_error_msg_and_die("not a block device");
+
+	// check if it is mounted
+	// N.B. what if we format a file? find_mount_point will return false negative since
+	// it is loop block device which mounted!
+	if (find_mount_point(argv[0], 0))
+		bb_error_msg_and_die("can't format mounted filesystem");
+
+	// open the device, get size in blocks
+	if (argv[1]) {
+		blocks = xatoull(argv[1]);
+		// seek past end fails on block devices but works on files
+		if (lseek(fd, blocks * blocksize - 1, SEEK_SET) != (off_t)-1) {
+			xwrite(fd, "", 1); // file grows if needed
+		}
+		//else {
+		//	bb_error_msg("warning, block device is smaller");
+		//}
+	} else {
+		blocks = (uoff_t)xlseek(fd, 0, SEEK_END) / blocksize;
+	}
+
+	// block number sanity check
+	// we have a limit: skipped area, super block, journal and root block
+	// all have to be addressed by one first bitmap
+	block = REISERFS_DISK_OFFSET_IN_BYTES / blocksize // boot area
+		+ 1		// sb
+		+ 1		// bitmap#0
+		+ journal_blocks+1	// journal
+	;
+
+	// count overhead
+	bitmap_blocks = (blocks - 1) / (blocksize * 8) + 1;
+	i = block + bitmap_blocks;
+
+	// check overhead
+	if (MIN(blocksize * 8, blocks) < i)
+		bb_error_msg_and_die("need >= %u blocks", i);
+
+	// ask confirmation?
+	// TODO: ???
+
+	// wipe out first REISERFS_DISK_OFFSET_IN_BYTES of device
+	// TODO: do we really need to wipe?!
+	xlseek(fd, REISERFS_DISK_OFFSET_IN_BYTES, SEEK_SET);
+
+	// fill superblock
+	sb = (struct reiserfs_super_block *)xzalloc(blocksize);
+	// block count
+	STORE_LE(sb->sb_block_count, blocks);
+	STORE_LE(sb->sb_free_blocks, blocks - i);
+	// TODO: decypher!
+	STORE_LE(sb->sb_root_block, block);
+	// fill journal related fields
+	jp = &sb->sb_journal;
+	STORE_LE(jp->jp_journal_1st_block, REISERFS_DISK_OFFSET_IN_BYTES / blocksize + 1/*sb*/ + 1/*bmp#0*/);
+	timestamp = time(NULL);
+	srandom(timestamp);
+	STORE_LE(jp->jp_journal_magic, random());
+	STORE_LE(jp->jp_journal_size, journal_blocks);
+	STORE_LE(jp->jp_journal_trans_max, JOURNAL_TRANS_MAX);
+	STORE_LE(jp->jp_journal_max_batch, JOURNAL_MAX_BATCH);
+	STORE_LE(jp->jp_journal_max_commit_age, JOURNAL_MAX_COMMIT_AGE);
+	// sizes
+	STORE_LE(sb->sb_blocksize, blocksize);
+	STORE_LE(sb->sb_oid_maxsize, (blocksize - sizeof(*sb)) / sizeof(uint32_t) / 2 * 2);
+	STORE_LE(sb->sb_oid_cursize, 2); // "." and ".."
+	strcpy(sb->s_magic, REISERFS_3_6_SUPER_MAGIC_STRING);
+	STORE_LE(sb->sb_bmap_nr, (bitmap_blocks > ((1LL << 16) - 1)) ? 0 : bitmap_blocks);
+	// misc
+	STORE_LE(sb->sb_version, REISERFS_FORMAT_3_6);
+	STORE_LE(sb->sb_lastcheck, timestamp);
+	STORE_LE(sb->sb_check_interval, DEFAULT_CHECK_INTERVAL);
+	STORE_LE(sb->sb_mnt_count, 1);
+	STORE_LE(sb->sb_max_mnt_count, DEFAULT_MAX_MNT_COUNT);
+	STORE_LE(sb->sb_umount_state, FS_CLEANLY_UMOUNTED);
+	STORE_LE(sb->sb_tree_height, 2);
+	STORE_LE(sb->sb_hash_function_code, 3); // R5_HASH
+	STORE_LE(sb->sb_flags, 1);
+	//STORE_LE(sb->sb_reserved_for_journal, 0);
+	// create UUID
+	generate_uuid(sb->s_uuid);
+	// write the label
+	safe_strncpy((char *)sb->s_label, label, sizeof(sb->s_label));
+
+	// TODO: EMPIRIC! ENDIANNESS!
+	// superblock has only 204 bytes. What are these?
+	buf = (uint8_t *)sb;
+	buf[205] = 1;
+	buf[209] = 3;
+
+	// put superblock
+	xwrite(fd, sb, blocksize);
+
+	// create bitmaps
+	buf = xzalloc(blocksize);
+
+	// bitmap #0 uses initial "block"+1 blocks
+	i = block + 1;
+	memset(buf, 0xFF, i / 8);
+	buf[i / 8] = (1 << (i & 7)) - 1; //0..7 => 00000000..01111111
+	// mark trailing absent blocks, if any
+	if (blocks < 8*blocksize) {
+		unsigned n = 8*blocksize - blocks;
+		i = n / 8;
+		buf[blocksize - i - 1] |= 0x7F00 >> (n & 7); //0..7 => 00000000..11111110
+		memset(buf + blocksize - i, 0xFF, i); // N.B. no overflow here!
+	}
+	// put bitmap #0
+	xwrite(fd, buf, blocksize);
+
+	// now go journal blocks
+	memset(buf, 0, blocksize);
+	for (i = 0; i < journal_blocks; i++)
+		xwrite(fd, buf, blocksize);
+	// dump journal control block
+	memcpy(&((struct reiserfs_journal_header *)buf)->jh_journal, &sb->sb_journal, sizeof(sb->sb_journal));
+	xwrite(fd, buf, blocksize);
+
+	// other bitmaps are in every (8*blocksize)-th block
+	// N.B. they use the only block -- namely bitmap itself!
+	buf[0] = 0x01;
+	// put bitmaps
+	for (i = 1; i < bitmap_blocks; i++) {
+		xlseek(fd, i*8*blocksize * blocksize, SEEK_SET);
+		// mark trailing absent blocks, if any
+		if (i == bitmap_blocks - 1 && (blocks % (8*blocksize))) {
+			unsigned n = 8*blocksize - blocks % (8*blocksize);
+			unsigned j = n / 8;
+			buf[blocksize - j - 1] |= 0x7F00 >> (n & 7); //0..7 => 00000000..11111110
+			memset(buf + blocksize - j, 0xFF, j); // N.B. no overflow here!
+		}
+		xwrite(fd, buf, blocksize);
+	}
+
+	// fill root block
+	// block head
+	memset(buf, 0, blocksize);
+	root = (struct block_head *)buf;
+	STORE_LE(root->blk2_level, 1); // leaf node
+	STORE_LE(root->blk2_nr_item, 2); // "." and ".."
+	STORE_LE(root->blk2_free_space, blocksize - sizeof(struct block_head));
+	// item head
+	// root directory
+	// TODO: EMPIRIC! ENDIANNESS!
+	// TODO: indented assignments seem to be timestamps
+buf[4] = 0134;
+buf[24] = 01;
+buf[28] = 02;
+buf[42] = 054;
+buf[44] = 0324;
+buf[45] = 017;
+buf[46] = 01;
+buf[48] = 01;
+buf[52] = 02;
+buf[56] = 01;
+buf[60] = 0364;
+buf[61] = 01;
+buf[64] = 02;
+buf[66] = 060;
+buf[68] = 0244;
+buf[69] = 017;
+buf[4004] = 01;
+buf[4008] = 01;
+buf[4012] = 02;
+buf[4016] = 050;
+buf[4018] = 04;
+buf[4020] = 02;
+buf[4028] = 01;
+buf[4032] = 040;
+buf[4034] = 04;
+
+buf[4036] = 056; buf[4037] = 056;	// ".."
+buf[4044] = 056;			// "."
+
+buf[4052] = 0355;
+buf[4053] = 0101;
+buf[4056] = 03;
+buf[4060] = 060;
+		buf[4076] = 0173;
+		buf[4077] = 0240;
+	buf[4078] = 0344;
+	buf[4079] = 0112;
+		buf[4080] = 0173;
+		buf[4081] = 0240;
+	buf[4082] = 0344;
+	buf[4083] = 0112;
+		buf[4084] = 0173;
+		buf[4085] = 0240;
+	buf[4086] = 0344;
+	buf[4087] = 0112;
+buf[4088] = 01;
+
+	// put root block
+	xlseek(fd, block * blocksize, SEEK_SET);
+	xwrite(fd, buf, blocksize);
+
+	// cleanup
+	if (ENABLE_FEATURE_CLEAN_UP) {
+		free(buf);
+		free(sb);
+	}
+
+	xclose(fd);
+	return EXIT_SUCCESS;
+}