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-rw-r--r--e2fslib/mkjournal.c408
1 files changed, 408 insertions, 0 deletions
diff --git a/e2fslib/mkjournal.c b/e2fslib/mkjournal.c
new file mode 100644
index 0000000..606501d
--- /dev/null
+++ b/e2fslib/mkjournal.c
@@ -0,0 +1,408 @@
+/*
+ * mkjournal.c --- make a journal for a filesystem
+ *
+ * Copyright (C) 2000 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include <fcntl.h>
+#include <time.h>
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#if HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#if HAVE_NETINET_IN_H
+#include <netinet/in.h>
+#endif
+
+#include "ext2_fs.h"
+#include "e2p/e2p.h"
+#include "ext2fs.h"
+#include "jfs_user.h"
+
+/*
+ * This function automatically sets up the journal superblock and
+ * returns it as an allocated block.
+ */
+errcode_t ext2fs_create_journal_superblock(ext2_filsys fs,
+ __u32 size, int flags,
+ char **ret_jsb)
+{
+ errcode_t retval;
+ journal_superblock_t *jsb;
+
+ if (size < 1024)
+ return EXT2_ET_JOURNAL_TOO_SMALL;
+
+ if ((retval = ext2fs_get_mem(fs->blocksize, (void **) &jsb)))
+ return retval;
+
+ memset (jsb, 0, fs->blocksize);
+
+ jsb->s_header.h_magic = htonl(JFS_MAGIC_NUMBER);
+ if (flags & EXT2_MKJOURNAL_V1_SUPER)
+ jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V1);
+ else
+ jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V2);
+ jsb->s_blocksize = htonl(fs->blocksize);
+ jsb->s_maxlen = htonl(size);
+ jsb->s_nr_users = htonl(1);
+ jsb->s_first = htonl(1);
+ jsb->s_sequence = htonl(1);
+ memcpy(jsb->s_uuid, fs->super->s_uuid, sizeof(fs->super->s_uuid));
+ /*
+ * If we're creating an external journal device, we need to
+ * adjust these fields.
+ */
+ if (fs->super->s_feature_incompat &
+ EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
+ jsb->s_nr_users = 0;
+ if (fs->blocksize == 1024)
+ jsb->s_first = htonl(3);
+ else
+ jsb->s_first = htonl(2);
+ }
+
+ *ret_jsb = (char *) jsb;
+ return 0;
+}
+
+/*
+ * This function writes a journal using POSIX routines. It is used
+ * for creating external journals and creating journals on live
+ * filesystems.
+ */
+static errcode_t write_journal_file(ext2_filsys fs, char *filename,
+ blk_t size, int flags)
+{
+ errcode_t retval;
+ char *buf = 0;
+ int i, fd, ret_size;
+
+ if ((retval = ext2fs_create_journal_superblock(fs, size, flags, &buf)))
+ return retval;
+
+ /* Open the device or journal file */
+ if ((fd = open(filename, O_WRONLY)) < 0) {
+ retval = errno;
+ goto errout;
+ }
+
+ /* Write the superblock out */
+ retval = EXT2_ET_SHORT_WRITE;
+ ret_size = write(fd, buf, fs->blocksize);
+ if (ret_size < 0) {
+ retval = errno;
+ goto errout;
+ }
+ if (ret_size != fs->blocksize)
+ goto errout;
+ memset(buf, 0, fs->blocksize);
+
+ for (i = 1; i < size; i++) {
+ ret_size = write(fd, buf, fs->blocksize);
+ if (ret_size < 0) {
+ retval = errno;
+ goto errout;
+ }
+ if (ret_size != fs->blocksize)
+ goto errout;
+ }
+ close(fd);
+
+ retval = 0;
+errout:
+ ext2fs_free_mem((void **) &buf);
+ return retval;
+}
+
+/*
+ * Helper function for creating the journal using direct I/O routines
+ */
+struct mkjournal_struct {
+ int num_blocks;
+ int newblocks;
+ char *buf;
+ errcode_t err;
+};
+
+static int mkjournal_proc(ext2_filsys fs,
+ blk_t *blocknr,
+ e2_blkcnt_t blockcnt,
+ blk_t ref_block,
+ int ref_offset,
+ void *priv_data)
+{
+ struct mkjournal_struct *es = (struct mkjournal_struct *) priv_data;
+ blk_t new_blk;
+ static blk_t last_blk = 0;
+ errcode_t retval;
+ int group;
+
+ if (*blocknr) {
+ last_blk = *blocknr;
+ return 0;
+ }
+ retval = ext2fs_new_block(fs, last_blk, 0, &new_blk);
+ if (retval) {
+ es->err = retval;
+ return BLOCK_ABORT;
+ }
+ if (blockcnt > 0)
+ es->num_blocks--;
+
+ es->newblocks++;
+ retval = io_channel_write_blk(fs->io, new_blk, 1, es->buf);
+
+ if (blockcnt == 0)
+ memset(es->buf, 0, fs->blocksize);
+
+ if (retval) {
+ es->err = retval;
+ return BLOCK_ABORT;
+ }
+ *blocknr = new_blk;
+ last_blk = new_blk;
+ ext2fs_mark_block_bitmap(fs->block_map, new_blk);
+ ext2fs_mark_bb_dirty(fs);
+ group = ext2fs_group_of_blk(fs, new_blk);
+ fs->group_desc[group].bg_free_blocks_count--;
+ fs->super->s_free_blocks_count--;
+ ext2fs_mark_super_dirty(fs);
+
+ if (es->num_blocks == 0)
+ return (BLOCK_CHANGED | BLOCK_ABORT);
+ else
+ return BLOCK_CHANGED;
+
+}
+
+/*
+ * This function creates a journal using direct I/O routines.
+ */
+static errcode_t write_journal_inode(ext2_filsys fs, ext2_ino_t journal_ino,
+ blk_t size, int flags)
+{
+ char *buf;
+ errcode_t retval;
+ struct ext2_inode inode;
+ struct mkjournal_struct es;
+
+ if ((retval = ext2fs_create_journal_superblock(fs, size, flags, &buf)))
+ return retval;
+
+ if ((retval = ext2fs_read_bitmaps(fs)))
+ return retval;
+
+ if ((retval = ext2fs_read_inode(fs, journal_ino, &inode)))
+ return retval;
+
+ if (inode.i_blocks > 0)
+ return EEXIST;
+
+ es.num_blocks = size;
+ es.newblocks = 0;
+ es.buf = buf;
+ es.err = 0;
+
+ retval = ext2fs_block_iterate2(fs, journal_ino, BLOCK_FLAG_APPEND,
+ 0, mkjournal_proc, &es);
+ if (es.err) {
+ retval = es.err;
+ goto errout;
+ }
+
+ if ((retval = ext2fs_read_inode(fs, journal_ino, &inode)))
+ goto errout;
+
+ inode.i_size += fs->blocksize * size;
+ inode.i_blocks += (fs->blocksize / 512) * es.newblocks;
+ inode.i_mtime = inode.i_ctime = time(0);
+ inode.i_links_count = 1;
+ inode.i_mode = LINUX_S_IFREG | 0600;
+
+ if ((retval = ext2fs_write_inode(fs, journal_ino, &inode)))
+ goto errout;
+ retval = 0;
+
+errout:
+ ext2fs_free_mem((void **) &buf);
+ return retval;
+}
+
+/*
+ * This function adds a journal device to a filesystem
+ */
+errcode_t ext2fs_add_journal_device(ext2_filsys fs, ext2_filsys journal_dev)
+{
+ struct stat st;
+ errcode_t retval;
+ char buf[1024];
+ journal_superblock_t *jsb;
+ int i, start;
+ __u32 nr_users;
+
+ /* Make sure the device exists and is a block device */
+ if (stat(journal_dev->device_name, &st) < 0)
+ return errno;
+
+ if (!S_ISBLK(st.st_mode))
+ return EXT2_ET_JOURNAL_NOT_BLOCK; /* Must be a block device */
+
+ /* Get the journal superblock */
+ start = 1;
+ if (journal_dev->blocksize == 1024)
+ start++;
+ if ((retval = io_channel_read_blk(journal_dev->io, start, -1024, buf)))
+ return retval;
+
+ jsb = (journal_superblock_t *) buf;
+ if ((jsb->s_header.h_magic != (unsigned) ntohl(JFS_MAGIC_NUMBER)) ||
+ (jsb->s_header.h_blocktype != (unsigned) ntohl(JFS_SUPERBLOCK_V2)))
+ return EXT2_ET_NO_JOURNAL_SB;
+
+ if (ntohl(jsb->s_blocksize) != fs->blocksize)
+ return EXT2_ET_UNEXPECTED_BLOCK_SIZE;
+
+ /* Check and see if this filesystem has already been added */
+ nr_users = ntohl(jsb->s_nr_users);
+ for (i=0; i < nr_users; i++) {
+ if (memcmp(fs->super->s_uuid,
+ &jsb->s_users[i*16], 16) == 0)
+ break;
+ }
+ if (i >= nr_users) {
+ memcpy(&jsb->s_users[nr_users*16],
+ fs->super->s_uuid, 16);
+ jsb->s_nr_users = htonl(nr_users+1);
+ }
+
+ /* Writeback the journal superblock */
+ if ((retval = io_channel_write_blk(journal_dev->io, start, -1024, buf)))
+ return retval;
+
+ fs->super->s_journal_inum = 0;
+ fs->super->s_journal_dev = st.st_rdev;
+ memcpy(fs->super->s_journal_uuid, jsb->s_uuid,
+ sizeof(fs->super->s_journal_uuid));
+ fs->super->s_feature_compat |= EXT3_FEATURE_COMPAT_HAS_JOURNAL;
+ ext2fs_mark_super_dirty(fs);
+ return 0;
+}
+
+/*
+ * This function adds a journal inode to a filesystem, using either
+ * POSIX routines if the filesystem is mounted, or using direct I/O
+ * functions if it is not.
+ */
+errcode_t ext2fs_add_journal_inode(ext2_filsys fs, blk_t size, int flags)
+{
+ errcode_t retval;
+ ext2_ino_t journal_ino;
+ struct stat st;
+ char jfile[1024];
+ int fd, mount_flags, f;
+
+ if ((retval = ext2fs_check_mount_point(fs->device_name, &mount_flags,
+ jfile, sizeof(jfile)-10)))
+ return retval;
+
+ if (mount_flags & EXT2_MF_MOUNTED) {
+ strcat(jfile, "/.journal");
+
+ /* Create the journal file */
+ if ((fd = open(jfile, O_CREAT|O_WRONLY, 0600)) < 0)
+ return errno;
+
+ if ((retval = write_journal_file(fs, jfile, size, flags)))
+ goto errout;
+
+ /* Get inode number of the journal file */
+ if (fstat(fd, &st) < 0)
+ goto errout;
+
+#if defined(HAVE_CHFLAGS) && defined(UF_NODUMP)
+ retval = fchflags (fd, UF_NODUMP|UF_IMMUTABLE);
+#else
+#if HAVE_EXT2_IOCTLS
+ f = EXT2_NODUMP_FL | EXT2_IMMUTABLE_FL;;
+ retval = ioctl(fd, EXT2_IOC_SETFLAGS, &f);
+#endif
+#endif
+ if (retval)
+ goto errout;
+
+ close(fd);
+ journal_ino = st.st_ino;
+ } else {
+ journal_ino = EXT2_JOURNAL_INO;
+ if ((retval = write_journal_inode(fs, journal_ino,
+ size, flags)))
+ return retval;
+ }
+
+ fs->super->s_journal_inum = journal_ino;
+ fs->super->s_journal_dev = 0;
+ memset(fs->super->s_journal_uuid, 0,
+ sizeof(fs->super->s_journal_uuid));
+ fs->super->s_feature_compat |= EXT3_FEATURE_COMPAT_HAS_JOURNAL;
+
+ ext2fs_mark_super_dirty(fs);
+ return 0;
+errout:
+ close(fd);
+ return retval;
+}
+
+#ifdef DEBUG
+main(int argc, char **argv)
+{
+ errcode_t retval;
+ char *device_name;
+ ext2_filsys fs;
+
+ if (argc < 2) {
+ fprintf(stderr, "Usage: %s filesystem\n", argv[0]);
+ exit(1);
+ }
+ device_name = argv[1];
+
+ retval = ext2fs_open (device_name, EXT2_FLAG_RW, 0, 0,
+ unix_io_manager, &fs);
+ if (retval) {
+ com_err(argv[0], retval, "while opening %s", device_name);
+ exit(1);
+ }
+
+ retval = ext2fs_add_journal_inode(fs, 1024);
+ if (retval) {
+ com_err(argv[0], retval, "while adding journal to %s",
+ device_name);
+ exit(1);
+ }
+ retval = ext2fs_flush(fs);
+ if (retval) {
+ printf("Warning, had trouble writing out superblocks.\n");
+ }
+ ext2fs_close(fs);
+ exit(0);
+
+}
+#endif