/*
* closefs.c --- close an ext2 filesystem
*
- * Copyright (C) 1993, 1994 Theodore Ts'o. This file may be redistributed
- * under the terms of the GNU Public License.
+ * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
*/
#include <stdio.h>
+#if HAVE_UNISTD_H
#include <unistd.h>
-#include <stdlib.h>
+#endif
#include <time.h>
+#include <string.h>
-#include <linux/fs.h>
-#include <linux/ext2_fs.h>
+#include "ext2_fs.h"
+#include "ext2fsP.h"
+
+static int test_root(int a, int b)
+{
+ if (a == 0)
+ return 1;
+ while (1) {
+ if (a == 1)
+ return 1;
+ if (a % b)
+ return 0;
+ a = a / b;
+ }
+}
+
+int ext2fs_bg_has_super(ext2_filsys fs, int group_block)
+{
+ if (!(fs->super->s_feature_ro_compat &
+ EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER))
+ return 1;
+
+ if (test_root(group_block, 3) || (test_root(group_block, 5)) ||
+ test_root(group_block, 7))
+ return 1;
+
+ return 0;
+}
+
+int ext2fs_super_and_bgd_loc(ext2_filsys fs,
+ dgrp_t group,
+ blk_t *ret_super_blk,
+ blk_t *ret_old_desc_blk,
+ blk_t *ret_new_desc_blk,
+ int *ret_meta_bg)
+{
+ blk_t group_block, super_blk = 0, old_desc_blk = 0, new_desc_blk = 0;
+ unsigned int meta_bg, meta_bg_size;
+ int numblocks, has_super;
+ int old_desc_blocks;
+
+ group_block = fs->super->s_first_data_block +
+ (group * fs->super->s_blocks_per_group);
+
+ if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
+ old_desc_blocks = fs->super->s_first_meta_bg;
+ else
+ old_desc_blocks =
+ fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
+
+ if (group == fs->group_desc_count-1) {
+ numblocks = (fs->super->s_blocks_count -
+ fs->super->s_first_data_block) %
+ fs->super->s_blocks_per_group;
+ if (!numblocks)
+ numblocks = fs->super->s_blocks_per_group;
+ } else
+ numblocks = fs->super->s_blocks_per_group;
+
+ has_super = ext2fs_bg_has_super(fs, group);
+
+ if (has_super) {
+ super_blk = group_block;
+ numblocks--;
+ }
+ meta_bg_size = (fs->blocksize / sizeof (struct ext2_group_desc));
+ meta_bg = group / meta_bg_size;
+
+ if (!(fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) ||
+ (meta_bg < fs->super->s_first_meta_bg)) {
+ if (has_super) {
+ old_desc_blk = group_block + 1;
+ numblocks -= old_desc_blocks;
+ }
+ } else {
+ if (((group % meta_bg_size) == 0) ||
+ ((group % meta_bg_size) == 1) ||
+ ((group % meta_bg_size) == (meta_bg_size-1))) {
+ if (has_super)
+ has_super = 1;
+ new_desc_blk = group_block + has_super;
+ numblocks--;
+ }
+ }
+
+ numblocks -= 2 + fs->inode_blocks_per_group;
+
+ if (ret_super_blk)
+ *ret_super_blk = super_blk;
+ if (ret_old_desc_blk)
+ *ret_old_desc_blk = old_desc_blk;
+ if (ret_new_desc_blk)
+ *ret_new_desc_blk = new_desc_blk;
+ if (ret_meta_bg)
+ *ret_meta_bg = meta_bg;
+ return (numblocks);
+}
+
+
+/*
+ * This function forces out the primary superblock. We need to only
+ * write out those fields which we have changed, since if the
+ * filesystem is mounted, it may have changed some of the other
+ * fields.
+ *
+ * It takes as input a superblock which has already been byte swapped
+ * (if necessary).
+ *
+ */
+static errcode_t write_primary_superblock(ext2_filsys fs,
+ struct ext2_super_block *super)
+{
+ __u16 *old_super, *new_super;
+ int check_idx, write_idx, size;
+ errcode_t retval;
+
+ if (!fs->io->manager->write_byte || !fs->orig_super) {
+ io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
+ retval = io_channel_write_blk(fs->io, 1, -SUPERBLOCK_SIZE,
+ super);
+ io_channel_set_blksize(fs->io, fs->blocksize);
+ return retval;
+ }
+
+ old_super = (__u16 *) fs->orig_super;
+ new_super = (__u16 *) super;
+
+ for (check_idx = 0; check_idx < SUPERBLOCK_SIZE/2; check_idx++) {
+ if (old_super[check_idx] == new_super[check_idx])
+ continue;
+ write_idx = check_idx;
+ for (check_idx++; check_idx < SUPERBLOCK_SIZE/2; check_idx++)
+ if (old_super[check_idx] == new_super[check_idx])
+ break;
+ size = 2 * (check_idx - write_idx);
+#if 0
+ printf("Writing %d bytes starting at %d\n",
+ size, write_idx*2);
+#endif
+ retval = io_channel_write_byte(fs->io,
+ SUPERBLOCK_OFFSET + (2 * write_idx), size,
+ new_super + write_idx);
+ if (retval)
+ return retval;
+ }
+ memcpy(fs->orig_super, super, SUPERBLOCK_SIZE);
+ return 0;
+}
+
+
+/*
+ * Updates the revision to EXT2_DYNAMIC_REV
+ */
+void ext2fs_update_dynamic_rev(ext2_filsys fs)
+{
+ struct ext2_super_block *sb = fs->super;
+
+ if (sb->s_rev_level > EXT2_GOOD_OLD_REV)
+ return;
+
+ sb->s_rev_level = EXT2_DYNAMIC_REV;
+ sb->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
+ sb->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
+ /* s_uuid is handled by e2fsck already */
+ /* other fields should be left alone */
+}
+
+static errcode_t write_backup_super(ext2_filsys fs, dgrp_t group,
+ blk_t group_block,
+ struct ext2_super_block *super_shadow)
+{
+ dgrp_t sgrp = group;
+
+ if (sgrp > ((1 << 16) - 1))
+ sgrp = (1 << 16) - 1;
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if (fs->flags & EXT2_FLAG_SWAP_BYTES)
+ super_shadow->s_block_group_nr = ext2fs_swab16(sgrp);
+ else
+#endif
+ fs->super->s_block_group_nr = sgrp;
+
+ return io_channel_write_blk(fs->io, group_block, -SUPERBLOCK_SIZE,
+ super_shadow);
+}
-#include "ext2fs.h"
errcode_t ext2fs_flush(ext2_filsys fs)
{
- int i,j;
- int group_block;
+ dgrp_t i,j;
+ blk_t group_block;
errcode_t retval;
- char *group_ptr;
+ unsigned long fs_state;
+ struct ext2_super_block *super_shadow = 0;
+ struct ext2_group_desc *group_shadow = 0;
+ struct ext2_group_desc *s, *t;
+ char *group_ptr;
+ int old_desc_blocks;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ fs_state = fs->super->s_state;
+
+ fs->super->s_wtime = fs->now ? fs->now : time(NULL);
+ fs->super->s_block_group_nr = 0;
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
+ retval = EXT2_ET_NO_MEMORY;
+ retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super_shadow);
+ if (retval)
+ goto errout;
+ retval = ext2fs_get_mem((size_t)(fs->blocksize *
+ fs->desc_blocks),
+ &group_shadow);
+ if (retval)
+ goto errout;
+ memset(group_shadow, 0, (size_t) fs->blocksize *
+ fs->desc_blocks);
+
+ /* swap the group descriptors */
+ for (j=0, s=fs->group_desc, t=group_shadow;
+ j < fs->group_desc_count; j++, t++, s++) {
+ *t = *s;
+ ext2fs_swap_group_desc(t);
+ }
+ } else {
+ super_shadow = fs->super;
+ group_shadow = fs->group_desc;
+ }
+#else
+ super_shadow = fs->super;
+ group_shadow = fs->group_desc;
+#endif
/*
- * Write out master superblock. This has to be done
- * separately, since it is located at a fixed location
- * (SUPERBLOCK_OFFSET).
+ * Set the state of the FS to be non-valid. (The state has
+ * already been backed up earlier, and will be restored after
+ * we write out the backup superblocks.)
*/
- fs->super->s_wtime = time(NULL);
- io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
- retval = io_channel_write_blk(fs->io, 1, -SUPERBLOCK_SIZE, fs->super);
- if (retval)
- return retval;
- io_channel_set_blksize(fs->io, fs->blocksize);
+ fs->super->s_state &= ~EXT2_VALID_FS;
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
+ *super_shadow = *fs->super;
+ ext2fs_swap_super(super_shadow);
+ }
+#endif
+
+ /*
+ * If this is an external journal device, don't write out the
+ * block group descriptors or any of the backup superblocks
+ */
+ if (fs->super->s_feature_incompat &
+ EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
+ goto write_primary_superblock_only;
/*
* Write out the master group descriptors, and the backup
* superblocks and group descriptors.
*/
group_block = fs->super->s_first_data_block;
+ group_ptr = (char *) group_shadow;
+ if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
+ old_desc_blocks = fs->super->s_first_meta_bg;
+ else
+ old_desc_blocks = fs->desc_blocks;
+
for (i = 0; i < fs->group_desc_count; i++) {
- if (i !=0 ) {
- retval = io_channel_write_blk(fs->io, group_block,
- -SUPERBLOCK_SIZE,
- fs->super);
+ blk_t super_blk, old_desc_blk, new_desc_blk;
+ int meta_bg;
+
+ ext2fs_super_and_bgd_loc(fs, i, &super_blk, &old_desc_blk,
+ &new_desc_blk, &meta_bg);
+
+ if (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) &&i && super_blk) {
+ retval = write_backup_super(fs, i, super_blk,
+ super_shadow);
if (retval)
- return retval;
+ goto errout;
}
- group_ptr = (char *) fs->group_desc;
- for (j=0; j < fs->desc_blocks; j++) {
+ if (fs->flags & EXT2_FLAG_SUPER_ONLY)
+ continue;
+ if ((old_desc_blk) &&
+ (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) || (i == 0))) {
retval = io_channel_write_blk(fs->io,
- group_block+1+j, 1,
- group_ptr);
+ old_desc_blk, old_desc_blocks, group_ptr);
if (retval)
- return retval;
- group_ptr += fs->blocksize;
+ goto errout;
+ }
+ if (new_desc_blk) {
+ retval = io_channel_write_blk(fs->io, new_desc_blk,
+ 1, group_ptr + (meta_bg*fs->blocksize));
+ if (retval)
+ goto errout;
}
- group_block += EXT2_BLOCKS_PER_GROUP(fs->super);
}
/*
if (fs->write_bitmaps) {
retval = fs->write_bitmaps(fs);
if (retval)
- return retval;
+ goto errout;
}
-
- return 0;
+
+write_primary_superblock_only:
+ /*
+ * Write out master superblock. This has to be done
+ * separately, since it is located at a fixed location
+ * (SUPERBLOCK_OFFSET). We flush all other pending changes
+ * out to disk first, just to avoid a race condition with an
+ * insy-tinsy window....
+ */
+
+ fs->super->s_block_group_nr = 0;
+ fs->super->s_state = fs_state;
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
+ *super_shadow = *fs->super;
+ ext2fs_swap_super(super_shadow);
+ }
+#endif
+
+ retval = io_channel_flush(fs->io);
+ retval = write_primary_superblock(fs, super_shadow);
+ if (retval)
+ goto errout;
+
+ fs->flags &= ~EXT2_FLAG_DIRTY;
+
+ retval = io_channel_flush(fs->io);
+errout:
+ fs->super->s_state = fs_state;
+ if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
+ if (super_shadow)
+ ext2fs_free_mem(&super_shadow);
+ if (group_shadow)
+ ext2fs_free_mem(&group_shadow);
+ }
+ return retval;
}
errcode_t ext2fs_close(ext2_filsys fs)
{
errcode_t retval;
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
if (fs->flags & EXT2_FLAG_DIRTY) {
retval = ext2fs_flush(fs);
if (retval)
return retval;
}
+ if (fs->write_bitmaps) {
+ retval = fs->write_bitmaps(fs);
+ if (retval)
+ return retval;
+ }
ext2fs_free(fs);
return 0;
}
+
git://git.whamcloud.com / tools / e2fsprogs.git / blobdiff