2 * mkjournal.c --- make a journal for a filesystem
4 * Copyright (C) 2000 Theodore Ts'o.
7 * This file may be redistributed under the terms of the GNU Public
26 #include <sys/types.h>
29 #include <sys/ioctl.h>
32 #include <netinet/in.h>
41 * This function automatically sets up the journal superblock and
42 * returns it as an allocated block.
44 errcode_t ext2fs_create_journal_superblock(ext2_filsys fs,
45 __u32 size, int flags,
49 journal_superblock_t *jsb;
52 return EXT2_ET_JOURNAL_TOO_SMALL;
54 if ((retval = ext2fs_get_mem(fs->blocksize, &jsb)))
57 memset (jsb, 0, fs->blocksize);
59 jsb->s_header.h_magic = htonl(JFS_MAGIC_NUMBER);
60 if (flags & EXT2_MKJOURNAL_V1_SUPER)
61 jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V1);
63 jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V2);
64 jsb->s_blocksize = htonl(fs->blocksize);
65 jsb->s_maxlen = htonl(size);
66 jsb->s_nr_users = htonl(1);
67 jsb->s_first = htonl(1);
68 jsb->s_sequence = htonl(1);
69 memcpy(jsb->s_uuid, fs->super->s_uuid, sizeof(fs->super->s_uuid));
71 * If we're creating an external journal device, we need to
72 * adjust these fields.
74 if (fs->super->s_feature_incompat &
75 EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
77 if (fs->blocksize == 1024)
78 jsb->s_first = htonl(3);
80 jsb->s_first = htonl(2);
83 *ret_jsb = (char *) jsb;
88 * This function writes a journal using POSIX routines. It is used
89 * for creating external journals and creating journals on live
92 static errcode_t write_journal_file(ext2_filsys fs, char *filename,
93 blk_t size, int flags)
100 if ((retval = ext2fs_create_journal_superblock(fs, size, flags, &buf)))
103 /* Open the device or journal file */
104 if ((fd = open(filename, O_WRONLY)) < 0) {
109 /* Write the superblock out */
110 retval = EXT2_ET_SHORT_WRITE;
111 ret_size = write(fd, buf, fs->blocksize);
116 if (ret_size != (int) fs->blocksize)
118 memset(buf, 0, fs->blocksize);
120 for (i = 1; i < size; i++) {
121 ret_size = write(fd, buf, fs->blocksize);
126 if (ret_size != (int) fs->blocksize)
133 ext2fs_free_mem(&buf);
138 * Helper function for creating the journal using direct I/O routines
140 struct mkjournal_struct {
147 static int mkjournal_proc(ext2_filsys fs,
149 e2_blkcnt_t blockcnt,
150 blk_t ref_block EXT2FS_ATTR((unused)),
151 int ref_offset EXT2FS_ATTR((unused)),
154 struct mkjournal_struct *es = (struct mkjournal_struct *) priv_data;
156 static blk_t last_blk = 0;
163 retval = ext2fs_new_block(fs, last_blk, 0, &new_blk);
172 retval = io_channel_write_blk(fs->io, new_blk, 1, es->buf);
175 memset(es->buf, 0, fs->blocksize);
183 ext2fs_block_alloc_stats(fs, new_blk, +1);
185 if (es->num_blocks == 0)
186 return (BLOCK_CHANGED | BLOCK_ABORT);
188 return BLOCK_CHANGED;
193 * This function creates a journal using direct I/O routines.
195 static errcode_t write_journal_inode(ext2_filsys fs, ext2_ino_t journal_ino,
196 blk_t size, int flags)
200 struct ext2_inode inode;
201 struct mkjournal_struct es;
203 if ((retval = ext2fs_create_journal_superblock(fs, size, flags, &buf)))
206 if ((retval = ext2fs_read_bitmaps(fs)))
209 if ((retval = ext2fs_read_inode(fs, journal_ino, &inode)))
212 if (inode.i_blocks > 0)
215 es.num_blocks = size;
220 retval = ext2fs_block_iterate2(fs, journal_ino, BLOCK_FLAG_APPEND,
221 0, mkjournal_proc, &es);
227 if ((retval = ext2fs_read_inode(fs, journal_ino, &inode)))
230 inode.i_size += fs->blocksize * size;
231 inode.i_blocks += (fs->blocksize / 512) * es.newblocks;
232 inode.i_mtime = inode.i_ctime = fs->now ? fs->now : time(0);
233 inode.i_links_count = 1;
234 inode.i_mode = LINUX_S_IFREG | 0600;
236 if ((retval = ext2fs_write_inode(fs, journal_ino, &inode)))
240 memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
241 fs->super->s_jnl_blocks[16] = inode.i_size;
242 fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
243 ext2fs_mark_super_dirty(fs);
246 ext2fs_free_mem(&buf);
251 * This function adds a journal device to a filesystem
253 errcode_t ext2fs_add_journal_device(ext2_filsys fs, ext2_filsys journal_dev)
258 journal_superblock_t *jsb;
262 /* Make sure the device exists and is a block device */
263 if (stat(journal_dev->device_name, &st) < 0)
266 if (!S_ISBLK(st.st_mode))
267 return EXT2_ET_JOURNAL_NOT_BLOCK; /* Must be a block device */
269 /* Get the journal superblock */
271 if (journal_dev->blocksize == 1024)
273 if ((retval = io_channel_read_blk(journal_dev->io, start, -1024, buf)))
276 jsb = (journal_superblock_t *) buf;
277 if ((jsb->s_header.h_magic != (unsigned) ntohl(JFS_MAGIC_NUMBER)) ||
278 (jsb->s_header.h_blocktype != (unsigned) ntohl(JFS_SUPERBLOCK_V2)))
279 return EXT2_ET_NO_JOURNAL_SB;
281 if (ntohl(jsb->s_blocksize) != (unsigned long) fs->blocksize)
282 return EXT2_ET_UNEXPECTED_BLOCK_SIZE;
284 /* Check and see if this filesystem has already been added */
285 nr_users = ntohl(jsb->s_nr_users);
286 for (i=0; i < nr_users; i++) {
287 if (memcmp(fs->super->s_uuid,
288 &jsb->s_users[i*16], 16) == 0)
292 memcpy(&jsb->s_users[nr_users*16],
293 fs->super->s_uuid, 16);
294 jsb->s_nr_users = htonl(nr_users+1);
297 /* Writeback the journal superblock */
298 if ((retval = io_channel_write_blk(journal_dev->io, start, -1024, buf)))
301 fs->super->s_journal_inum = 0;
302 fs->super->s_journal_dev = st.st_rdev;
303 memcpy(fs->super->s_journal_uuid, jsb->s_uuid,
304 sizeof(fs->super->s_journal_uuid));
305 fs->super->s_feature_compat |= EXT3_FEATURE_COMPAT_HAS_JOURNAL;
306 ext2fs_mark_super_dirty(fs);
311 * This function adds a journal inode to a filesystem, using either
312 * POSIX routines if the filesystem is mounted, or using direct I/O
313 * functions if it is not.
315 errcode_t ext2fs_add_journal_inode(ext2_filsys fs, blk_t size, int flags)
318 ext2_ino_t journal_ino;
324 if ((retval = ext2fs_check_mount_point(fs->device_name, &mount_flags,
325 jfile, sizeof(jfile)-10)))
328 if (mount_flags & EXT2_MF_MOUNTED) {
329 strcat(jfile, "/.journal");
332 * If .../.journal already exists, make sure any
333 * immutable or append-only flags are cleared.
335 #if defined(HAVE_CHFLAGS) && defined(UF_NODUMP)
336 (void) chflags (jfile, 0);
339 fd = open(jfile, O_RDONLY);
342 ioctl(fd, EXT2_IOC_SETFLAGS, &f);
348 /* Create the journal file */
349 if ((fd = open(jfile, O_CREAT|O_WRONLY, 0600)) < 0)
352 if ((retval = write_journal_file(fs, jfile, size, flags)))
355 /* Get inode number of the journal file */
356 if (fstat(fd, &st) < 0)
359 #if defined(HAVE_CHFLAGS) && defined(UF_NODUMP)
360 retval = fchflags (fd, UF_NODUMP|UF_IMMUTABLE);
363 f = EXT2_NODUMP_FL | EXT2_IMMUTABLE_FL;
364 retval = ioctl(fd, EXT2_IOC_SETFLAGS, &f);
371 journal_ino = st.st_ino;
373 if ((mount_flags & EXT2_MF_BUSY) &&
374 !(fs->flags & EXT2_FLAG_EXCLUSIVE)) {
378 journal_ino = EXT2_JOURNAL_INO;
379 if ((retval = write_journal_inode(fs, journal_ino,
384 fs->super->s_journal_inum = journal_ino;
385 fs->super->s_journal_dev = 0;
386 memset(fs->super->s_journal_uuid, 0,
387 sizeof(fs->super->s_journal_uuid));
388 fs->super->s_feature_compat |= EXT3_FEATURE_COMPAT_HAS_JOURNAL;
390 ext2fs_mark_super_dirty(fs);
399 main(int argc, char **argv)
406 fprintf(stderr, "Usage: %s filesystem\n", argv[0]);
409 device_name = argv[1];
411 retval = ext2fs_open (device_name, EXT2_FLAG_RW, 0, 0,
412 unix_io_manager, &fs);
414 com_err(argv[0], retval, "while opening %s", device_name);
418 retval = ext2fs_add_journal_inode(fs, 1024);
420 com_err(argv[0], retval, "while adding journal to %s",
424 retval = ext2fs_flush(fs);
426 printf("Warning, had trouble writing out superblocks.\n");