From 464df1d5e5ab1322e2dd0a7796939fff1aeefa9a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:49:25 +0200 Subject: Adding upstream version 1.47.0. Signed-off-by: Daniel Baumann --- lib/ext2fs/closefs.c | 521 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 521 insertions(+) create mode 100644 lib/ext2fs/closefs.c (limited to 'lib/ext2fs/closefs.c') diff --git a/lib/ext2fs/closefs.c b/lib/ext2fs/closefs.c new file mode 100644 index 0000000..69cbdd8 --- /dev/null +++ b/lib/ext2fs/closefs.c @@ -0,0 +1,521 @@ +/* + * 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 +#if HAVE_UNISTD_H +#include +#endif +#include +#include + +#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; +} + -- cgit v1.2.3