From 2f919710143cb2025157c3c193ee22de86f3ed73 Mon Sep 17 00:00:00 2001 From: Yongqiang Yang Date: Wed, 27 Jul 2011 21:16:33 -0400 Subject: [PATCH] ext4: simplify parameters of add_new_gdb() add_new_gdb() only needs the block group number; there is no need to pass a pointer to struct ext4_new_group_data to add_new_gdb(). Instead of filling in a pointer the struct buffer_head in add_new_gdb(), it's simpler to have the caller fetch it from the s_group_desc[] array. [Fixed error path to handle the case where struct buffer_head *primary hasn't been set yet. -- Ted] Signed-off-by: Yongqiang Yang Signed-off-by: "Theodore Ts'o" --- fs/ext4/resize.c | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 65e5cb6c094d..9e453552f10e 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -394,15 +394,15 @@ static int verify_reserved_gdb(struct super_block *sb, * fail once we start modifying the data on disk, because JBD has no rollback. */ static int add_new_gdb(handle_t *handle, struct inode *inode, - struct ext4_new_group_data *input, - struct buffer_head **primary) + ext4_group_t group) { struct super_block *sb = inode->i_sb; struct ext4_super_block *es = EXT4_SB(sb)->s_es; - unsigned long gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb); + unsigned long gdb_num = group / EXT4_DESC_PER_BLOCK(sb); ext4_fsblk_t gdblock = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num; struct buffer_head **o_group_desc, **n_group_desc; struct buffer_head *dind; + struct buffer_head *gdb_bh; int gdbackups; struct ext4_iloc iloc; __le32 *data; @@ -425,11 +425,12 @@ static int add_new_gdb(handle_t *handle, struct inode *inode, return -EPERM; } - *primary = sb_bread(sb, gdblock); - if (!*primary) + gdb_bh = sb_bread(sb, gdblock); + if (!gdb_bh) return -EIO; - if ((gdbackups = verify_reserved_gdb(sb, *primary)) < 0) { + gdbackups = verify_reserved_gdb(sb, gdb_bh); + if (gdbackups < 0) { err = gdbackups; goto exit_bh; } @@ -444,7 +445,7 @@ static int add_new_gdb(handle_t *handle, struct inode *inode, data = (__le32 *)dind->b_data; if (le32_to_cpu(data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)]) != gdblock) { ext4_warning(sb, "new group %u GDT block %llu not reserved", - input->group, gdblock); + group, gdblock); err = -EINVAL; goto exit_dind; } @@ -453,7 +454,7 @@ static int add_new_gdb(handle_t *handle, struct inode *inode, if (unlikely(err)) goto exit_dind; - err = ext4_journal_get_write_access(handle, *primary); + err = ext4_journal_get_write_access(handle, gdb_bh); if (unlikely(err)) goto exit_sbh; @@ -492,8 +493,8 @@ static int add_new_gdb(handle_t *handle, struct inode *inode, } inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9; ext4_mark_iloc_dirty(handle, inode, &iloc); - memset((*primary)->b_data, 0, sb->s_blocksize); - err = ext4_handle_dirty_metadata(handle, NULL, *primary); + memset(gdb_bh->b_data, 0, sb->s_blocksize); + err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh); if (unlikely(err)) { ext4_std_error(sb, err); goto exit_inode; @@ -503,7 +504,7 @@ static int add_new_gdb(handle_t *handle, struct inode *inode, o_group_desc = EXT4_SB(sb)->s_group_desc; memcpy(n_group_desc, o_group_desc, EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *)); - n_group_desc[gdb_num] = *primary; + n_group_desc[gdb_num] = gdb_bh; EXT4_SB(sb)->s_group_desc = n_group_desc; EXT4_SB(sb)->s_gdb_count++; kfree(o_group_desc); @@ -525,7 +526,7 @@ exit_sbh: exit_dind: brelse(dind); exit_bh: - brelse(*primary); + brelse(gdb_bh); ext4_debug("leaving with error %d\n", err); return err; @@ -833,8 +834,16 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) if (reserved_gdb && ext4_bg_num_gdb(sb, input->group) && (err = reserve_backup_gdb(handle, inode, input))) goto exit_journal; - } else if ((err = add_new_gdb(handle, inode, input, &primary))) - goto exit_journal; + } else { + /* + * Note that we can access new group descriptor block safely + * only if add_new_gdb() succeeds. + */ + err = add_new_gdb(handle, inode, input->group); + if (err) + goto exit_journal; + primary = sbi->s_group_desc[gdb_num]; + } /* * OK, now we've set up the new group. Time to make it active. @@ -944,7 +953,7 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) exit_journal: if ((err2 = ext4_journal_stop(handle)) && !err) err = err2; - if (!err) { + if (!err && primary) { update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es, sizeof(struct ext4_super_block)); update_backups(sb, primary->b_blocknr, primary->b_data, -- 2.20.1