From c14c6fd5c56a0d0495d8a7c0f2bc330be658663e Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Mon, 28 Jan 2008 23:58:26 -0500 Subject: ext4: Add EXT4_IOC_MIGRATE ioctl The below patch add ioctl for migrating ext3 indirect block mapped inode to ext4 extent mapped inode. Signed-off-by: Aneesh Kumar K.V --- fs/ext4/migrate.c | 560 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 560 insertions(+) create mode 100644 fs/ext4/migrate.c (limited to 'fs/ext4/migrate.c') diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c new file mode 100644 index 00000000000..ec7cb567a7d --- /dev/null +++ b/fs/ext4/migrate.c @@ -0,0 +1,560 @@ +/* + * Copyright IBM Corporation, 2007 + * Author Aneesh Kumar K.V + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2.1 of the GNU Lesser General Public License + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + */ + +#include +#include +#include + +/* + * The contiguous blocks details which can be + * represented by a single extent + */ +struct list_blocks_struct { + ext4_lblk_t first_block, last_block; + ext4_fsblk_t first_pblock, last_pblock; +}; + +static int finish_range(handle_t *handle, struct inode *inode, + struct list_blocks_struct *lb) + +{ + int retval = 0, needed; + struct ext4_extent newext; + struct ext4_ext_path *path; + if (lb->first_pblock == 0) + return 0; + + /* Add the extent to temp inode*/ + newext.ee_block = cpu_to_le32(lb->first_block); + newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1); + ext4_ext_store_pblock(&newext, lb->first_pblock); + path = ext4_ext_find_extent(inode, lb->first_block, NULL); + + if (IS_ERR(path)) { + retval = PTR_ERR(path); + goto err_out; + } + + /* + * Calculate the credit needed to inserting this extent + * Since we are doing this in loop we may accumalate extra + * credit. But below we try to not accumalate too much + * of them by restarting the journal. + */ + needed = ext4_ext_calc_credits_for_insert(inode, path); + + /* + * Make sure the credit we accumalated is not really high + */ + if (needed && handle->h_buffer_credits >= EXT4_RESERVE_TRANS_BLOCKS) { + retval = ext4_journal_restart(handle, needed); + if (retval) + goto err_out; + } + if (needed) { + retval = ext4_journal_extend(handle, needed); + if (retval != 0) { + /* + * IF not able to extend the journal restart the journal + */ + retval = ext4_journal_restart(handle, needed); + if (retval) + goto err_out; + } + } + retval = ext4_ext_insert_extent(handle, inode, path, &newext); +err_out: + lb->first_pblock = 0; + return retval; +} + +static int update_extent_range(handle_t *handle, struct inode *inode, + ext4_fsblk_t pblock, ext4_lblk_t blk_num, + struct list_blocks_struct *lb) +{ + int retval; + /* + * See if we can add on to the existing range (if it exists) + */ + if (lb->first_pblock && + (lb->last_pblock+1 == pblock) && + (lb->last_block+1 == blk_num)) { + lb->last_pblock = pblock; + lb->last_block = blk_num; + return 0; + } + /* + * Start a new range. + */ + retval = finish_range(handle, inode, lb); + lb->first_pblock = lb->last_pblock = pblock; + lb->first_block = lb->last_block = blk_num; + + return retval; +} + +static int update_ind_extent_range(handle_t *handle, struct inode *inode, + ext4_fsblk_t pblock, ext4_lblk_t *blk_nump, + struct list_blocks_struct *lb) +{ + struct buffer_head *bh; + __le32 *i_data; + int i, retval = 0; + ext4_lblk_t blk_count = *blk_nump; + unsigned long max_entries = inode->i_sb->s_blocksize >> 2; + + if (!pblock) { + /* Only update the file block number */ + *blk_nump += max_entries; + return 0; + } + + bh = sb_bread(inode->i_sb, pblock); + if (!bh) + return -EIO; + + i_data = (__le32 *)bh->b_data; + for (i = 0; i < max_entries; i++, blk_count++) { + if (i_data[i]) { + retval = update_extent_range(handle, inode, + le32_to_cpu(i_data[i]), + blk_count, lb); + if (retval) + break; + } + } + + /* Update the file block number */ + *blk_nump = blk_count; + put_bh(bh); + return retval; + +} + +static int update_dind_extent_range(handle_t *handle, struct inode *inode, + ext4_fsblk_t pblock, ext4_lblk_t *blk_nump, + struct list_blocks_struct *lb) +{ + struct buffer_head *bh; + __le32 *i_data; + int i, retval = 0; + ext4_lblk_t blk_count = *blk_nump; + unsigned long max_entries = inode->i_sb->s_blocksize >> 2; + + if (!pblock) { + /* Only update the file block number */ + *blk_nump += max_entries * max_entries; + return 0; + } + bh = sb_bread(inode->i_sb, pblock); + if (!bh) + return -EIO; + + i_data = (__le32 *)bh->b_data; + for (i = 0; i < max_entries; i++) { + if (i_data[i]) { + retval = update_ind_extent_range(handle, inode, + le32_to_cpu(i_data[i]), + &blk_count, lb); + if (retval) + break; + } else { + /* Only update the file block number */ + blk_count += max_entries; + } + } + + /* Update the file block number */ + *blk_nump = blk_count; + put_bh(bh); + return retval; + +} + +static int update_tind_extent_range(handle_t *handle, struct inode *inode, + ext4_fsblk_t pblock, ext4_lblk_t *blk_nump, + struct list_blocks_struct *lb) +{ + struct buffer_head *bh; + __le32 *i_data; + int i, retval = 0; + ext4_lblk_t blk_count = *blk_nump; + unsigned long max_entries = inode->i_sb->s_blocksize >> 2; + + if (!pblock) { + /* Only update the file block number */ + *blk_nump += max_entries * max_entries * max_entries; + return 0; + } + bh = sb_bread(inode->i_sb, pblock); + if (!bh) + return -EIO; + + i_data = (__le32 *)bh->b_data; + for (i = 0; i < max_entries; i++) { + if (i_data[i]) { + retval = update_dind_extent_range(handle, inode, + le32_to_cpu(i_data[i]), + &blk_count, lb); + if (retval) + break; + } else + /* Only update the file block number */ + blk_count += max_entries * max_entries; + } + /* Update the file block number */ + *blk_nump = blk_count; + put_bh(bh); + return retval; + +} + +static int free_dind_blocks(handle_t *handle, + struct inode *inode, __le32 i_data) +{ + int i; + __le32 *tmp_idata; + struct buffer_head *bh; + unsigned long max_entries = inode->i_sb->s_blocksize >> 2; + + bh = sb_bread(inode->i_sb, le32_to_cpu(i_data)); + if (!bh) + return -EIO; + + tmp_idata = (__le32 *)bh->b_data; + for (i = 0; i < max_entries; i++) { + if (tmp_idata[i]) + ext4_free_blocks(handle, inode, + le32_to_cpu(tmp_idata[i]), 1); + } + put_bh(bh); + ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1); + return 0; +} + +static int free_tind_blocks(handle_t *handle, + struct inode *inode, __le32 i_data) +{ + int i, retval = 0; + __le32 *tmp_idata; + struct buffer_head *bh; + unsigned long max_entries = inode->i_sb->s_blocksize >> 2; + + bh = sb_bread(inode->i_sb, le32_to_cpu(i_data)); + if (!bh) + return -EIO; + + tmp_idata = (__le32 *)bh->b_data; + for (i = 0; i < max_entries; i++) { + if (tmp_idata[i]) { + retval = free_dind_blocks(handle, + inode, tmp_idata[i]); + if (retval) { + put_bh(bh); + return retval; + } + } + } + put_bh(bh); + ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1); + return 0; +} + +static int free_ind_block(handle_t *handle, struct inode *inode) +{ + int retval; + struct ext4_inode_info *ei = EXT4_I(inode); + + if (ei->i_data[EXT4_IND_BLOCK]) + ext4_free_blocks(handle, inode, + le32_to_cpu(ei->i_data[EXT4_IND_BLOCK]), 1); + + if (ei->i_data[EXT4_DIND_BLOCK]) { + retval = free_dind_blocks(handle, inode, + ei->i_data[EXT4_DIND_BLOCK]); + if (retval) + return retval; + } + + if (ei->i_data[EXT4_TIND_BLOCK]) { + retval = free_tind_blocks(handle, inode, + ei->i_data[EXT4_TIND_BLOCK]); + if (retval) + return retval; + } + return 0; +} + +static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode, + struct inode *tmp_inode, int retval) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode); + + retval = free_ind_block(handle, inode); + if (retval) + goto err_out; + + /* + * One credit accounted for writing the + * i_data field of the original inode + */ + retval = ext4_journal_extend(handle, 1); + if (retval != 0) { + retval = ext4_journal_restart(handle, 1); + if (retval) + goto err_out; + } + + /* + * We have the extent map build with the tmp inode. + * Now copy the i_data across + */ + ei->i_flags |= EXT4_EXTENTS_FL; + memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data)); + + /* + * Update i_blocks with the new blocks that got + * allocated while adding extents for extent index + * blocks. + * + * While converting to extents we need not + * update the orignal inode i_blocks for extent blocks + * via quota APIs. The quota update happened via tmp_inode already. + */ + spin_lock(&inode->i_lock); + inode->i_blocks += tmp_inode->i_blocks; + spin_unlock(&inode->i_lock); + + ext4_mark_inode_dirty(handle, inode); +err_out: + return retval; +} + +static int free_ext_idx(handle_t *handle, struct inode *inode, + struct ext4_extent_idx *ix) +{ + int i, retval = 0; + ext4_fsblk_t block; + struct buffer_head *bh; + struct ext4_extent_header *eh; + + block = idx_pblock(ix); + bh = sb_bread(inode->i_sb, block); + if (!bh) + return -EIO; + + eh = (struct ext4_extent_header *)bh->b_data; + if (eh->eh_depth != 0) { + ix = EXT_FIRST_INDEX(eh); + for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) { + retval = free_ext_idx(handle, inode, ix); + if (retval) + break; + } + } + put_bh(bh); + ext4_free_blocks(handle, inode, block, 1); + return retval; +} + +/* + * Free the extent meta data blocks only + */ +static int free_ext_block(handle_t *handle, struct inode *inode) +{ + int i, retval = 0; + struct ext4_inode_info *ei = EXT4_I(inode); + struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data; + struct ext4_extent_idx *ix; + if (eh->eh_depth == 0) + /* + * No extra blocks allocated for extent meta data + */ + return 0; + ix = EXT_FIRST_INDEX(eh); + for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) { + retval = free_ext_idx(handle, inode, ix); + if (retval) + return retval; + } + return retval; + +} + +int ext4_ext_migrate(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + handle_t *handle; + int retval = 0, i; + __le32 *i_data; + ext4_lblk_t blk_count = 0; + struct ext4_inode_info *ei; + struct inode *tmp_inode = NULL; + struct list_blocks_struct lb; + unsigned long max_entries; + + if (!test_opt(inode->i_sb, EXTENTS)) + /* + * if mounted with noextents we don't allow the migrate + */ + return -EINVAL; + + if ((EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) + return -EINVAL; + + down_write(&EXT4_I(inode)->i_data_sem); + handle = ext4_journal_start(inode, + EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + + EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 + + 2 * EXT4_QUOTA_INIT_BLOCKS(inode->i_sb) + + 1); + if (IS_ERR(handle)) { + retval = PTR_ERR(handle); + goto err_out; + } + tmp_inode = ext4_new_inode(handle, + inode->i_sb->s_root->d_inode, + S_IFREG); + if (IS_ERR(tmp_inode)) { + retval = -ENOMEM; + ext4_journal_stop(handle); + tmp_inode = NULL; + goto err_out; + } + i_size_write(tmp_inode, i_size_read(inode)); + /* + * We don't want the inode to be reclaimed + * if we got interrupted in between. We have + * this tmp inode carrying reference to the + * data blocks of the original file. We set + * the i_nlink to zero at the last stage after + * switching the original file to extent format + */ + tmp_inode->i_nlink = 1; + + ext4_ext_tree_init(handle, tmp_inode); + ext4_orphan_add(handle, tmp_inode); + ext4_journal_stop(handle); + + ei = EXT4_I(inode); + i_data = ei->i_data; + memset(&lb, 0, sizeof(lb)); + + /* 32 bit block address 4 bytes */ + max_entries = inode->i_sb->s_blocksize >> 2; + + /* + * start with one credit accounted for + * superblock modification. + * + * For the tmp_inode we already have commited the + * trascation that created the inode. Later as and + * when we add extents we extent the journal + */ + handle = ext4_journal_start(inode, 1); + for (i = 0; i < EXT4_NDIR_BLOCKS; i++, blk_count++) { + if (i_data[i]) { + retval = update_extent_range(handle, tmp_inode, + le32_to_cpu(i_data[i]), + blk_count, &lb); + if (retval) + goto err_out; + } + } + if (i_data[EXT4_IND_BLOCK]) { + retval = update_ind_extent_range(handle, tmp_inode, + le32_to_cpu(i_data[EXT4_IND_BLOCK]), + &blk_count, &lb); + if (retval) + goto err_out; + } else + blk_count += max_entries; + if (i_data[EXT4_DIND_BLOCK]) { + retval = update_dind_extent_range(handle, tmp_inode, + le32_to_cpu(i_data[EXT4_DIND_BLOCK]), + &blk_count, &lb); + if (retval) + goto err_out; + } else + blk_count += max_entries * max_entries; + if (i_data[EXT4_TIND_BLOCK]) { + retval = update_tind_extent_range(handle, tmp_inode, + le32_to_cpu(i_data[EXT4_TIND_BLOCK]), + &blk_count, &lb); + if (retval) + goto err_out; + } + /* + * Build the last extent + */ + retval = finish_range(handle, tmp_inode, &lb); +err_out: + /* + * We are either freeing extent information or indirect + * blocks. During this we touch superblock, group descriptor + * and block bitmap. Later we mark the tmp_inode dirty + * via ext4_ext_tree_init. So allocate a credit of 4 + * We may update quota (user and group). + * + * FIXME!! we may be touching bitmaps in different block groups. + */ + if (ext4_journal_extend(handle, + 4 + 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb)) != 0) + ext4_journal_restart(handle, + 4 + 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb)); + if (retval) + /* + * Failure case delete the extent information with the + * tmp_inode + */ + free_ext_block(handle, tmp_inode); + else + retval = ext4_ext_swap_inode_data(handle, inode, + tmp_inode, retval); + + /* + * Mark the tmp_inode as of size zero + */ + i_size_write(tmp_inode, 0); + + /* + * set the i_blocks count to zero + * so that the ext4_delete_inode does the + * right job + * + * We don't need to take the i_lock because + * the inode is not visible to user space. + */ + tmp_inode->i_blocks = 0; + + /* Reset the extent details */ + ext4_ext_tree_init(handle, tmp_inode); + + /* + * Set the i_nlink to zero so that + * generic_drop_inode really deletes the + * inode + */ + tmp_inode->i_nlink = 0; + + ext4_journal_stop(handle); + + up_write(&EXT4_I(inode)->i_data_sem); + + if (tmp_inode) + iput(tmp_inode); + + return retval; +} -- cgit v1.2.3