[thirdparty/e2fsprogs.git] / lib / ext2fs / closefs.c

/*
 * closefs.c --- close an ext2 filesystem
 *
 * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
 *
 * %Begin-Header%
 * This file may be redistributed under the terms of the GNU Library
 * General Public License, version 2.
 * %End-Header%
 */

#include "config.h"
#include <stdio.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <time.h>
#include <string.h>

#include "ext2_fs.h"
#include "ext2fsP.h"

static int test_root(unsigned int a, unsigned int b)
{
	while (1) {
		if (a < b)
			return 0;
		if (a == b)
			return 1;
		if (a % b)
			return 0;
		a = a / b;
	}
}

int ext2fs_bg_has_super(ext2_filsys fs, dgrp_t group)
{
	if (group == 0)
		return 1;
	if (ext2fs_has_feature_sparse_super2(fs->super)) {
		if (group == fs->super->s_backup_bgs[0] ||
		    group == fs->super->s_backup_bgs[1])
			return 1;
		return 0;
	}
	if ((group <= 1) || !ext2fs_has_feature_sparse_super(fs->super))
		return 1;
	if (!(group & 1))
		return 0;
	if (test_root(group, 3) || (test_root(group, 5)) ||
	    test_root(group, 7))
		return 1;

	return 0;
}

/*
 * ext2fs_super_and_bgd_loc2()
 * @fs:			ext2 fs pointer
 * @group		given block group
 * @ret_super_blk:	if !NULL, returns super block location
 * @ret_old_desc_blk:	if !NULL, returns location of the old block
 *			group descriptor
 * @ret_new_desc_blk:	if !NULL, returns location of meta_bg block
 *			group descriptor
 * @ret_used_blks:	if !NULL, returns number of blocks used by
 *			super block and group_descriptors.
 *
 * Returns errcode_t of 0
 */
errcode_t ext2fs_super_and_bgd_loc2(ext2_filsys fs,
					   dgrp_t group,
					   blk64_t *ret_super_blk,
					   blk64_t *ret_old_desc_blk,
					   blk64_t *ret_new_desc_blk,
					   blk_t *ret_used_blks)
{
	blk64_t	group_block, super_blk = 0, old_desc_blk = 0, new_desc_blk = 0;
	unsigned int meta_bg, meta_bg_size;
	blk_t	numblocks = 0;
	blk64_t old_desc_blocks;
	int	has_super;

	group_block = ext2fs_group_first_block2(fs, group);
	if (group_block == 0 && fs->blocksize == 1024)
		group_block = 1; /* Deal with 1024 blocksize && bigalloc */

	if (ext2fs_has_feature_meta_bg(fs->super))
		old_desc_blocks = fs->super->s_first_meta_bg;
	else
		old_desc_blocks =
			fs->desc_blocks + fs->super->s_reserved_gdt_blocks;

	has_super = ext2fs_bg_has_super(fs, group);

	if (has_super) {
		super_blk = group_block;
		numblocks++;
	}
	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
	meta_bg = group / meta_bg_size;

	if (!ext2fs_has_feature_meta_bg(fs->super) ||
	    (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++;
		}
	}

	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_used_blks)
		*ret_used_blks = numblocks;

	return 0;
}

/*
 * This function returns the location of the superblock, block group
 * descriptors for a given block group.  It currently returns the
 * number of free blocks assuming that inode table and allocation
 * bitmaps will be in the group.  This is not necessarily the case
 * when the flex_bg feature is enabled, so callers should take care!
 * It was only really intended for use by mke2fs, and even there it's
 * not that useful.
 *
 * The ext2fs_super_and_bgd_loc2() function is 64-bit block number
 * capable and returns the number of blocks used by super block and
 * group descriptors.
 */
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)
{
	blk64_t ret_super_blk2;
	blk64_t ret_old_desc_blk2;
	blk64_t ret_new_desc_blk2;
	blk_t ret_used_blks;
	blk_t numblocks;
	unsigned int meta_bg_size;

	ext2fs_super_and_bgd_loc2(fs, group, &ret_super_blk2,
					&ret_old_desc_blk2,
					&ret_new_desc_blk2,
					&ret_used_blks);

	numblocks = ext2fs_group_blocks_count(fs, group);

	if (ret_super_blk)
		*ret_super_blk = (blk_t)ret_super_blk2;
	if (ret_old_desc_blk)
		*ret_old_desc_blk = (blk_t)ret_old_desc_blk2;
	if (ret_new_desc_blk)
		*ret_new_desc_blk = (blk_t)ret_new_desc_blk2;
	if (ret_meta_bg) {
		meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
		*ret_meta_bg = group / meta_bg_size;
	}

	numblocks -= 2 + fs->inode_blocks_per_group + ret_used_blks;

	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) {
	fallback:
		io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
		retval = io_channel_write_blk64(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 == EXT2_ET_UNIMPLEMENTED)
			goto fallback;
		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,
				    blk64_t group_block,
				    struct ext2_super_block *super_shadow)
{
	errcode_t retval;
	dgrp_t	sgrp = group;

	if (sgrp > ((1 << 16) - 1))
		sgrp = (1 << 16) - 1;

	super_shadow->s_block_group_nr = ext2fs_cpu_to_le16(sgrp);

	retval = ext2fs_superblock_csum_set(fs, super_shadow);
	if (retval)
		return retval;

	return io_channel_write_blk64(fs->io, group_block, -SUPERBLOCK_SIZE,
				    super_shadow);
}

errcode_t ext2fs_flush(ext2_filsys fs)
{
	return ext2fs_flush2(fs, 0);
}

errcode_t ext2fs_flush2(ext2_filsys fs, int flags)
{
	dgrp_t		i;
	errcode_t	retval;
	unsigned long	fs_state;
	__u32		feature_incompat;
	struct ext2_super_block *super_shadow = 0;
	struct opaque_ext2_group_desc *group_shadow = 0;
#ifdef WORDS_BIGENDIAN
	struct ext2_group_desc *gdp;
	dgrp_t		j;
#endif
	char	*group_ptr;
	blk64_t	old_desc_blocks;
	struct ext2fs_numeric_progress_struct progress;

	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

	if ((fs->flags & EXT2_FLAG_SUPER_ONLY) == 0 &&
	    !ext2fs_has_feature_journal_dev(fs->super) &&
	    fs->group_desc == NULL)
		return EXT2_ET_NO_GDESC;

	fs_state = fs->super->s_state;
	feature_incompat = fs->super->s_feature_incompat;

	fs->super->s_wtime = fs->now ? fs->now : time(NULL);
	fs->super->s_block_group_nr = 0;

	/*
	 * If the write_bitmaps() function is present, call it to
	 * flush the bitmaps.  This is done this way so that a simple
	 * program that doesn't mess with the bitmaps doesn't need to
	 * drag in the bitmaps.c code.
	 *
	 * Bitmap checksums live in the group descriptor, so the
	 * bitmaps need to be written before the descriptors.
	 */
	if (fs->write_bitmaps) {
		retval = fs->write_bitmaps(fs);
		if (retval)
			goto errout;
	}

	/*
	 * 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_state &= ~EXT2_VALID_FS;
	ext2fs_clear_feature_journal_needs_recovery(fs->super);

	/* Byte swap the superblock and the group descriptors if necessary */
#ifdef WORDS_BIGENDIAN
	retval = EXT2_ET_NO_MEMORY;
	retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super_shadow);
	if (retval)
		goto errout;
	memcpy(super_shadow, fs->super, sizeof(struct ext2_super_block));
	ext2fs_swap_super(super_shadow);

	if (((fs->flags & EXT2_FLAG_SUPER_ONLY) == 0) &&
	    !ext2fs_has_feature_journal_dev(fs->super)) {
		retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
					  &group_shadow);
		if (retval)
			goto errout;
		memcpy(group_shadow, fs->group_desc, (size_t) fs->blocksize *
		       fs->desc_blocks);

		for (j = 0; j < fs->group_desc_count; j++) {
			gdp = ext2fs_group_desc(fs, group_shadow, j);
			ext2fs_swap_group_desc2(fs, gdp);
		}
	}
#else
	super_shadow = fs->super;
	group_shadow = fs->group_desc;
#endif

	/*
	 * If this is an external journal device, don't write out the
	 * block group descriptors or any of the backup superblocks
	 */
	if (ext2fs_has_feature_journal_dev(fs->super))
		goto write_primary_superblock_only;

	/*
	 * Write out the master group descriptors, and the backup
	 * superblocks and group descriptors.
	 */
	group_ptr = (char *) group_shadow;
	if (ext2fs_has_feature_meta_bg(fs->super)) {
		old_desc_blocks = fs->super->s_first_meta_bg;
		if (old_desc_blocks > fs->desc_blocks)
			old_desc_blocks = fs->desc_blocks;
	} else
		old_desc_blocks = fs->desc_blocks;

	if (fs->progress_ops && fs->progress_ops->init)
		(fs->progress_ops->init)(fs, &progress, NULL,
					 fs->group_desc_count);


	for (i = 0; i < fs->group_desc_count; i++) {
		blk64_t	super_blk, old_desc_blk, new_desc_blk;

		if (fs->progress_ops && fs->progress_ops->update)
			(fs->progress_ops->update)(fs, &progress, i);
		ext2fs_super_and_bgd_loc2(fs, i, &super_blk, &old_desc_blk,
					 &new_desc_blk, 0);

		if (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) &&i && super_blk) {
			retval = write_backup_super(fs, i, super_blk,
						    super_shadow);
			if (retval)
				goto errout;
		}
		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_blk64(fs->io,
			      old_desc_blk, old_desc_blocks, group_ptr);
			if (retval)
				goto errout;
		}
		if (new_desc_blk) {
			int meta_bg = i / EXT2_DESC_PER_BLOCK(fs->super);

			retval = io_channel_write_blk64(fs->io, new_desc_blk,
				1, group_ptr + (meta_bg*fs->blocksize));
			if (retval)
				goto errout;
		}
	}

	if (fs->progress_ops && fs->progress_ops->close)
		(fs->progress_ops->close)(fs, &progress, NULL);

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;
	fs->super->s_feature_incompat = feature_incompat;
#ifdef WORDS_BIGENDIAN
	*super_shadow = *fs->super;
	ext2fs_swap_super(super_shadow);
#endif

	retval = ext2fs_superblock_csum_set(fs, super_shadow);
	if (retval)
		return retval;

	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC)) {
		retval = io_channel_flush(fs->io);
		if (retval)
			goto errout;
	}
	retval = write_primary_superblock(fs, super_shadow);
	if (retval)
		goto errout;

	fs->flags &= ~EXT2_FLAG_DIRTY;

	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC)) {
		retval = io_channel_flush(fs->io);
		if (retval)
			goto errout;
	}
errout:
	fs->super->s_state = fs_state;
#ifdef WORDS_BIGENDIAN
	if (super_shadow)
		ext2fs_free_mem(&super_shadow);
	if (group_shadow)
		ext2fs_free_mem(&group_shadow);
#endif
	return retval;
}

errcode_t ext2fs_close_free(ext2_filsys *fs_ptr)
{
	errcode_t ret;
	ext2_filsys fs = *fs_ptr;

	ret = ext2fs_close2(fs, 0);
	if (ret)
		ext2fs_free(fs);
	*fs_ptr = NULL;
	return ret;
}

errcode_t ext2fs_close(ext2_filsys fs)
{
	return ext2fs_close2(fs, 0);
}

errcode_t ext2fs_close2(ext2_filsys fs, int flags)
{
	errcode_t	retval;
	int		meta_blks;
	io_stats stats = 0;

	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

	if (fs->write_bitmaps) {
		retval = fs->write_bitmaps(fs);
		if (retval)
			return retval;
	}
	if (fs->super->s_kbytes_written &&
	    fs->io->manager->get_stats)
		fs->io->manager->get_stats(fs->io, &stats);
	if (stats && stats->bytes_written && (fs->flags & EXT2_FLAG_RW)) {
		fs->super->s_kbytes_written += stats->bytes_written >> 10;
		meta_blks = fs->desc_blocks + 1;
		if (!(fs->flags & EXT2_FLAG_SUPER_ONLY))
			fs->super->s_kbytes_written += meta_blks /
				(fs->blocksize / 1024);
		if ((fs->flags & EXT2_FLAG_DIRTY) == 0)
			fs->flags |= EXT2_FLAG_SUPER_ONLY | EXT2_FLAG_DIRTY;
	}
	if (fs->flags & EXT2_FLAG_DIRTY) {
		retval = ext2fs_flush2(fs, flags);
		if (retval)
			return retval;
	}

	retval = ext2fs_mmp_stop(fs);
	if (retval)
		return retval;

	ext2fs_free(fs);
	return 0;
}
Commit	Line	Data
3839e657 TT	1	/*
3839e657 TT	2	* closefs.c --- close an ext2 filesystem
efc6f628	3	*
21c84b71 TT	4	* Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
	5	*
	6	* %Begin-Header%
543547a5 TT	7	* This file may be redistributed under the terms of the GNU Library
543547a5 TT	8	* General Public License, version 2.
21c84b71	9	* %End-Header%
3839e657 TT	10	*/
3839e657 TT	11
d1154eb4	12	#include "config.h"
3839e657	13	#include <stdio.h>
4cbe8af4	14	#if HAVE_UNISTD_H
3839e657	15	#include <unistd.h>
4cbe8af4	16	#endif
3839e657	17	#include <time.h>
50e1e10f	18	#include <string.h>
3839e657	19
b5abe6fa	20	#include "ext2_fs.h"
21c84b71	21	#include "ext2fsP.h"
3839e657	22
47183951	23	static int test_root(unsigned int a, unsigned int b)
1b4cd9c7	24	{
1b4cd9c7	25	while (1) {
47183951 TT	26	if (a < b)
	27	return 0;
	28	if (a == b)
1b4cd9c7 TT	29	return 1;
	30	if (a % b)
	31	return 0;
	32	a = a / b;
	33	}
	34	}
	35
47183951	36	int ext2fs_bg_has_super(ext2_filsys fs, dgrp_t group)
1b4cd9c7	37	{
65c6c3e0 TT	38	if (group == 0)
65c6c3e0 TT	39	return 1;
77b3e987	40	if (ext2fs_has_feature_sparse_super2(fs->super)) {
65c6c3e0 TT	41	if (group == fs->super->s_backup_bgs[0] \|\|
	42	group == fs->super->s_backup_bgs[1])
	43	return 1;
	44	return 0;
	45	}
77b3e987	46	if ((group <= 1) \|\| !ext2fs_has_feature_sparse_super(fs->super))
1b4cd9c7	47	return 1;
47183951 TT	48	if (!(group & 1))
	49	return 0;
	50	if (test_root(group, 3) \|\| (test_root(group, 5)) \|\|
	51	test_root(group, 7))
1b4cd9c7 TT	52	return 1;
	53
	54	return 0;
	55	}
	56
4a568505	57	/*
71300f35 JS	58	* ext2fs_super_and_bgd_loc2()
	59	* @fs: ext2 fs pointer
	60	* @group given block group
	61	* @ret_super_blk: if !NULL, returns super block location
	62	* @ret_old_desc_blk: if !NULL, returns location of the old block
	63	* group descriptor
	64	* @ret_new_desc_blk: if !NULL, returns location of meta_bg block
	65	* group descriptor
	66	* @ret_used_blks: if !NULL, returns number of blocks used by
	67	* super block and group_descriptors.
4a568505	68	*
71300f35	69	* Returns errcode_t of 0
4a568505	70	*/
71300f35 JS	71	errcode_t ext2fs_super_and_bgd_loc2(ext2_filsys fs,
	72	dgrp_t group,
	73	blk64_t *ret_super_blk,
	74	blk64_t *ret_old_desc_blk,
	75	blk64_t *ret_new_desc_blk,
	76	blk_t *ret_used_blks)
ef344e13	77	{
71300f35	78	blk64_t group_block, super_blk = 0, old_desc_blk = 0, new_desc_blk = 0;
54434927	79	unsigned int meta_bg, meta_bg_size;
71300f35 JS	80	blk_t numblocks = 0;
71300f35 JS	81	blk64_t old_desc_blocks;
5d38ef1d	82	int has_super;
ef344e13	83
71300f35	84	group_block = ext2fs_group_first_block2(fs, group);
25567a7b TT	85	if (group_block == 0 && fs->blocksize == 1024)
25567a7b TT	86	group_block = 1; /* Deal with 1024 blocksize && bigalloc */
ef344e13	87
77b3e987	88	if (ext2fs_has_feature_meta_bg(fs->super))
ef344e13 TT	89	old_desc_blocks = fs->super->s_first_meta_bg;
ef344e13 TT	90	else
efc6f628	91	old_desc_blocks =
d323f8fb	92	fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
ef344e13	93
ef344e13 TT	94	has_super = ext2fs_bg_has_super(fs, group);
	95
	96	if (has_super) {
	97	super_blk = group_block;
71300f35	98	numblocks++;
ef344e13	99	}
f2de1d38	100	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
ef344e13 TT	101	meta_bg = group / meta_bg_size;
ef344e13 TT	102
77b3e987	103	if (!ext2fs_has_feature_meta_bg(fs->super) \|\|
ef344e13 TT	104	(meta_bg < fs->super->s_first_meta_bg)) {
	105	if (has_super) {
	106	old_desc_blk = group_block + 1;
71300f35	107	numblocks += old_desc_blocks;
ef344e13 TT	108	}
	109	} else {
	110	if (((group % meta_bg_size) == 0) \|\|
	111	((group % meta_bg_size) == 1) \|\|
	112	((group % meta_bg_size) == (meta_bg_size-1))) {
	113	if (has_super)
	114	has_super = 1;
	115	new_desc_blk = group_block + has_super;
71300f35	116	numblocks++;
ef344e13 TT	117	}
ef344e13 TT	118	}
efc6f628	119
ef344e13 TT	120	if (ret_super_blk)
	121	*ret_super_blk = super_blk;
	122	if (ret_old_desc_blk)
	123	*ret_old_desc_blk = old_desc_blk;
	124	if (ret_new_desc_blk)
	125	*ret_new_desc_blk = new_desc_blk;
71300f35 JS	126	if (ret_used_blks)
	127	*ret_used_blks = numblocks;
	128
	129	return 0;
ef344e13 TT	130	}
ef344e13 TT	131
71300f35 JS	132	/*
	133	* This function returns the location of the superblock, block group
	134	* descriptors for a given block group. It currently returns the
	135	* number of free blocks assuming that inode table and allocation
	136	* bitmaps will be in the group. This is not necessarily the case
	137	* when the flex_bg feature is enabled, so callers should take care!
	138	* It was only really intended for use by mke2fs, and even there it's
	139	* not that useful.
	140	*
	141	* The ext2fs_super_and_bgd_loc2() function is 64-bit block number
	142	* capable and returns the number of blocks used by super block and
	143	* group descriptors.
	144	*/
	145	int ext2fs_super_and_bgd_loc(ext2_filsys fs,
	146	dgrp_t group,
	147	blk_t *ret_super_blk,
	148	blk_t *ret_old_desc_blk,
	149	blk_t *ret_new_desc_blk,
	150	int *ret_meta_bg)
	151	{
	152	blk64_t ret_super_blk2;
	153	blk64_t ret_old_desc_blk2;
	154	blk64_t ret_new_desc_blk2;
	155	blk_t ret_used_blks;
	156	blk_t numblocks;
	157	unsigned int meta_bg_size;
	158
	159	ext2fs_super_and_bgd_loc2(fs, group, &ret_super_blk2,
	160	&ret_old_desc_blk2,
	161	&ret_new_desc_blk2,
	162	&ret_used_blks);
	163
98f45471	164	numblocks = ext2fs_group_blocks_count(fs, group);
71300f35 JS	165
	166	if (ret_super_blk)
	167	*ret_super_blk = (blk_t)ret_super_blk2;
	168	if (ret_old_desc_blk)
	169	*ret_old_desc_blk = (blk_t)ret_old_desc_blk2;
	170	if (ret_new_desc_blk)
	171	*ret_new_desc_blk = (blk_t)ret_new_desc_blk2;
	172	if (ret_meta_bg) {
	173	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
	174	*ret_meta_bg = group / meta_bg_size;
	175	}
	176
	177	numblocks -= 2 + fs->inode_blocks_per_group + ret_used_blks;
	178
	179	return numblocks;
	180	}
ef344e13	181
c180ac86 TT	182	/*
	183	* This function forces out the primary superblock. We need to only
	184	* write out those fields which we have changed, since if the
	185	* filesystem is mounted, it may have changed some of the other
	186	* fields.
	187	*
	188	* It takes as input a superblock which has already been byte swapped
	189	* (if necessary).
	190	*
	191	*/
	192	static errcode_t write_primary_superblock(ext2_filsys fs,
	193	struct ext2_super_block *super)
	194	{
	195	__u16 old_super, new_super;
	196	int check_idx, write_idx, size;
	197	errcode_t retval;
	198
	199	if (!fs->io->manager->write_byte \|\| !fs->orig_super) {
7f1a1fbf	200	fallback:
c180ac86	201	io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
24a117ab	202	retval = io_channel_write_blk64(fs->io, 1, -SUPERBLOCK_SIZE,
c180ac86 TT	203	super);
	204	io_channel_set_blksize(fs->io, fs->blocksize);
	205	return retval;
	206	}
	207
	208	old_super = (__u16 *) fs->orig_super;
	209	new_super = (__u16 *) super;
	210
	211	for (check_idx = 0; check_idx < SUPERBLOCK_SIZE/2; check_idx++) {
	212	if (old_super[check_idx] == new_super[check_idx])
	213	continue;
	214	write_idx = check_idx;
	215	for (check_idx++; check_idx < SUPERBLOCK_SIZE/2; check_idx++)
	216	if (old_super[check_idx] == new_super[check_idx])
	217	break;
	218	size = 2 * (check_idx - write_idx);
	219	#if 0
	220	printf("Writing %d bytes starting at %d\n",
	221	size, write_idx*2);
	222	#endif
	223	retval = io_channel_write_byte(fs->io,
	224	SUPERBLOCK_OFFSET + (2 * write_idx), size,
	225	new_super + write_idx);
7f1a1fbf TT	226	if (retval == EXT2_ET_UNIMPLEMENTED)
7f1a1fbf TT	227	goto fallback;
c180ac86 TT	228	if (retval)
	229	return retval;
	230	}
3c6b8977	231	memcpy(fs->orig_super, super, SUPERBLOCK_SIZE);
c180ac86 TT	232	return 0;
	233	}
	234
	235
3fe973b3 TT	236	/*
	237	* Updates the revision to EXT2_DYNAMIC_REV
	238	*/
a917d1cc	239	void ext2fs_update_dynamic_rev(ext2_filsys fs)
3fe973b3 TT	240	{
	241	struct ext2_super_block *sb = fs->super;
	242
	243	if (sb->s_rev_level > EXT2_GOOD_OLD_REV)
	244	return;
	245
	246	sb->s_rev_level = EXT2_DYNAMIC_REV;
	247	sb->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
	248	sb->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
	249	/* s_uuid is handled by e2fsck already */
	250	/* other fields should be left alone */
	251	}
	252
c046ac7f	253	static errcode_t write_backup_super(ext2_filsys fs, dgrp_t group,
4dbfd79d	254	blk64_t group_block,
c046ac7f TT	255	struct ext2_super_block *super_shadow)
c046ac7f TT	256	{
d4ca3e40	257	errcode_t retval;
c046ac7f	258	dgrp_t sgrp = group;
efc6f628	259
c046ac7f TT	260	if (sgrp > ((1 << 16) - 1))
c046ac7f TT	261	sgrp = (1 << 16) - 1;
d4ca3e40	262
ebc8d3ca TT	263	super_shadow->s_block_group_nr = ext2fs_cpu_to_le16(sgrp);
ebc8d3ca TT	264
d4ca3e40 DW	265	retval = ext2fs_superblock_csum_set(fs, super_shadow);
	266	if (retval)
	267	return retval;
c046ac7f	268
24a117ab	269	return io_channel_write_blk64(fs->io, group_block, -SUPERBLOCK_SIZE,
c046ac7f TT	270	super_shadow);
	271	}
	272
3839e657	273	errcode_t ext2fs_flush(ext2_filsys fs)
9d9a53e6 RJ	274	{
	275	return ext2fs_flush2(fs, 0);
	276	}
	277
	278	errcode_t ext2fs_flush2(ext2_filsys fs, int flags)
3839e657	279	{
2d328bb7	280	dgrp_t i;
3839e657	281	errcode_t retval;
f3db3566	282	unsigned long fs_state;
9a083af7	283	__u32 feature_incompat;
50e1e10f	284	struct ext2_super_block *super_shadow = 0;
c8a1566d	285	struct opaque_ext2_group_desc *group_shadow = 0;
2d328bb7	286	#ifdef WORDS_BIGENDIAN
1d18a55c	287	struct ext2_group_desc *gdp;
2d328bb7 TT	288	dgrp_t j;
2d328bb7 TT	289	#endif
ef344e13	290	char *group_ptr;
49d0fe2a	291	blk64_t old_desc_blocks;
95fd65bb	292	struct ext2fs_numeric_progress_struct progress;
efc6f628	293
f3db3566 TT	294	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
f3db3566 TT	295
c8651b4b TT	296	if ((fs->flags & EXT2_FLAG_SUPER_ONLY) == 0 &&
	297	!ext2fs_has_feature_journal_dev(fs->super) &&
	298	fs->group_desc == NULL)
	299	return EXT2_ET_NO_GDESC;
	300
50e1e10f	301	fs_state = fs->super->s_state;
9a083af7	302	feature_incompat = fs->super->s_feature_incompat;
50e1e10f	303
32138187	304	fs->super->s_wtime = fs->now ? fs->now : time(NULL);
e5b38a5f	305	fs->super->s_block_group_nr = 0;
a80ea340 DW	306
	307	/*
	308	* If the write_bitmaps() function is present, call it to
	309	* flush the bitmaps. This is done this way so that a simple
	310	* program that doesn't mess with the bitmaps doesn't need to
	311	* drag in the bitmaps.c code.
	312	*
	313	* Bitmap checksums live in the group descriptor, so the
	314	* bitmaps need to be written before the descriptors.
	315	*/
	316	if (fs->write_bitmaps) {
	317	retval = fs->write_bitmaps(fs);
	318	if (retval)
	319	goto errout;
	320	}
	321
ebc8d3ca TT	322	/*
	323	* Set the state of the FS to be non-valid. (The state has
	324	* already been backed up earlier, and will be restored after
	325	* we write out the backup superblocks.)
	326	*/
	327	fs->super->s_state &= ~EXT2_VALID_FS;
	328	ext2fs_clear_feature_journal_needs_recovery(fs->super);
	329
	330	/* Byte swap the superblock and the group descriptors if necessary */
126a291c TT	331	#ifdef WORDS_BIGENDIAN
	332	retval = EXT2_ET_NO_MEMORY;
	333	retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super_shadow);
126a291c TT	334	if (retval)
126a291c TT	335	goto errout;
d4ca3e40	336	memcpy(super_shadow, fs->super, sizeof(struct ext2_super_block));
ebc8d3ca	337	ext2fs_swap_super(super_shadow);
df659444 TT	338
	339	if (((fs->flags & EXT2_FLAG_SUPER_ONLY) == 0) &&
	340	!ext2fs_has_feature_journal_dev(fs->super)) {
	341	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
	342	&group_shadow);
	343	if (retval)
	344	goto errout;
	345	memcpy(group_shadow, fs->group_desc, (size_t) fs->blocksize *
	346	fs->desc_blocks);
	347
	348	for (j = 0; j < fs->group_desc_count; j++) {
	349	gdp = ext2fs_group_desc(fs, group_shadow, j);
	350	ext2fs_swap_group_desc2(fs, gdp);
	351	}
50e1e10f	352	}
5df55d7f TT	353	#else
5df55d7f TT	354	super_shadow = fs->super;
c8a1566d	355	group_shadow = fs->group_desc;
5df55d7f	356	#endif
efc6f628	357
0d961040 TT	358	/*
	359	* If this is an external journal device, don't write out the
	360	* block group descriptors or any of the backup superblocks
	361	*/
77b3e987	362	if (ext2fs_has_feature_journal_dev(fs->super))
0d961040 TT	363	goto write_primary_superblock_only;
0d961040 TT	364
3839e657 TT	365	/*
	366	* Write out the master group descriptors, and the backup
	367	* superblocks and group descriptors.
	368	*/
ef344e13	369	group_ptr = (char *) group_shadow;
77b3e987	370	if (ext2fs_has_feature_meta_bg(fs->super)) {
ef344e13	371	old_desc_blocks = fs->super->s_first_meta_bg;
49d0fe2a	372	if (old_desc_blocks > fs->desc_blocks)
f66e6ce4 TT	373	old_desc_blocks = fs->desc_blocks;
f66e6ce4 TT	374	} else
ef344e13 TT	375	old_desc_blocks = fs->desc_blocks;
ef344e13 TT	376
dfe74c5c TT	377	if (fs->progress_ops && fs->progress_ops->init)
	378	(fs->progress_ops->init)(fs, &progress, NULL,
	379	fs->group_desc_count);
95fd65bb VAH	380
95fd65bb VAH	381
bfd41883	382	for (i = 0; i < fs->group_desc_count; i++) {
20f2ccb3	383	blk64_t super_blk, old_desc_blk, new_desc_blk;
ef344e13	384
dfe74c5c TT	385	if (fs->progress_ops && fs->progress_ops->update)
dfe74c5c TT	386	(fs->progress_ops->update)(fs, &progress, i);
20f2ccb3 JS	387	ext2fs_super_and_bgd_loc2(fs, i, &super_blk, &old_desc_blk,
20f2ccb3 JS	388	&new_desc_blk, 0);
ef344e13 TT	389
	390	if (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) &&i && super_blk) {
	391	retval = write_backup_super(fs, i, super_blk,
c046ac7f	392	super_shadow);
50e1e10f TT	393	if (retval)
50e1e10f TT	394	goto errout;
3839e657	395	}
ef344e13 TT	396	if (fs->flags & EXT2_FLAG_SUPER_ONLY)
ef344e13 TT	397	continue;
efc6f628	398	if ((old_desc_blk) &&
ef344e13	399	(!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) \|\| (i == 0))) {
24a117ab	400	retval = io_channel_write_blk64(fs->io,
ef344e13 TT	401	old_desc_blk, old_desc_blocks, group_ptr);
	402	if (retval)
	403	goto errout;
	404	}
	405	if (new_desc_blk) {
20f2ccb3 JS	406	int meta_bg = i / EXT2_DESC_PER_BLOCK(fs->super);
20f2ccb3 JS	407
24a117ab	408	retval = io_channel_write_blk64(fs->io, new_desc_blk,
ef344e13 TT	409	1, group_ptr + (meta_bg*fs->blocksize));
ef344e13 TT	410	if (retval)
50e1e10f	411	goto errout;
3839e657	412	}
3839e657 TT	413	}
3839e657 TT	414
dfe74c5c TT	415	if (fs->progress_ops && fs->progress_ops->close)
dfe74c5c TT	416	(fs->progress_ops->close)(fs, &progress, NULL);
95fd65bb	417
a63d1267	418	write_primary_superblock_only:
b5abe6fa	419	/*
a63d1267 TT	420	* Write out master superblock. This has to be done
	421	* separately, since it is located at a fixed location
	422	* (SUPERBLOCK_OFFSET). We flush all other pending changes
	423	* out to disk first, just to avoid a race condition with an
	424	* insy-tinsy window....
b5abe6fa	425	*/
0d961040 TT	426
	427	fs->super->s_block_group_nr = 0;
	428	fs->super->s_state = fs_state;
9a083af7	429	fs->super->s_feature_incompat = feature_incompat;
126a291c TT	430	#ifdef WORDS_BIGENDIAN
	431	super_shadow = fs->super;
	432	ext2fs_swap_super(super_shadow);
0d961040 TT	433	#endif
0d961040 TT	434
d4ca3e40 DW	435	retval = ext2fs_superblock_csum_set(fs, super_shadow);
	436	if (retval)
	437	return retval;
	438
025d31b1	439	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC)) {
9d9a53e6	440	retval = io_channel_flush(fs->io);
025d31b1 ES	441	if (retval)
	442	goto errout;
	443	}
a63d1267 TT	444	retval = write_primary_superblock(fs, super_shadow);
	445	if (retval)
	446	goto errout;
	447
	448	fs->flags &= ~EXT2_FLAG_DIRTY;
	449
025d31b1	450	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC)) {
9d9a53e6	451	retval = io_channel_flush(fs->io);
025d31b1 ES	452	if (retval)
	453	goto errout;
	454	}
50e1e10f TT	455	errout:
50e1e10f TT	456	fs->super->s_state = fs_state;
126a291c TT	457	#ifdef WORDS_BIGENDIAN
	458	if (super_shadow)
	459	ext2fs_free_mem(&super_shadow);
	460	if (group_shadow)
	461	ext2fs_free_mem(&group_shadow);
	462	#endif
50e1e10f	463	return retval;
3839e657 TT	464	}
3839e657 TT	465
47fee2ef LC	466	errcode_t ext2fs_close_free(ext2_filsys *fs_ptr)
	467	{
	468	errcode_t ret;
	469	ext2_filsys fs = *fs_ptr;
	470
	471	ret = ext2fs_close2(fs, 0);
	472	if (ret)
	473	ext2fs_free(fs);
	474	*fs_ptr = NULL;
	475	return ret;
	476	}
	477
3839e657	478	errcode_t ext2fs_close(ext2_filsys fs)
9d9a53e6 RJ	479	{
	480	return ext2fs_close2(fs, 0);
	481	}
	482
	483	errcode_t ext2fs_close2(ext2_filsys fs, int flags)
3839e657 TT	484	{
3839e657 TT	485	errcode_t retval;
b7c5b403 TT	486	int meta_blks;
b7c5b403 TT	487	io_stats stats = 0;
efc6f628	488
f3db3566 TT	489	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
f3db3566 TT	490
b7c5b403 TT	491	if (fs->write_bitmaps) {
b7c5b403 TT	492	retval = fs->write_bitmaps(fs);
3839e657 TT	493	if (retval)
	494	return retval;
	495	}
b7c5b403 TT	496	if (fs->super->s_kbytes_written &&
	497	fs->io->manager->get_stats)
	498	fs->io->manager->get_stats(fs->io, &stats);
	499	if (stats && stats->bytes_written && (fs->flags & EXT2_FLAG_RW)) {
	500	fs->super->s_kbytes_written += stats->bytes_written >> 10;
	501	meta_blks = fs->desc_blocks + 1;
	502	if (!(fs->flags & EXT2_FLAG_SUPER_ONLY))
	503	fs->super->s_kbytes_written += meta_blks /
	504	(fs->blocksize / 1024);
6d67ee30 TT	505	if ((fs->flags & EXT2_FLAG_DIRTY) == 0)
6d67ee30 TT	506	fs->flags \|= EXT2_FLAG_SUPER_ONLY \| EXT2_FLAG_DIRTY;
b7c5b403 TT	507	}
b7c5b403 TT	508	if (fs->flags & EXT2_FLAG_DIRTY) {
9d9a53e6	509	retval = ext2fs_flush2(fs, flags);
21c84b71 TT	510	if (retval)
	511	return retval;
	512	}
0f5eba75 AD	513
	514	retval = ext2fs_mmp_stop(fs);
	515	if (retval)
	516	return retval;
	517
3839e657 TT	518	ext2fs_free(fs);
	519	return 0;
	520	}
21c84b71	521