| /* |
| * Copyright IBM Corporation, 2007 |
| * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> |
| * |
| * 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 <linux/slab.h> |
| #include "ext4_jbd2.h" |
| #include "ext4_extents.h" |
| |
| /* |
| * The contiguous blocks details which can be |
| * represented by a single extent |
| */ |
| struct migrate_struct { |
| ext4_lblk_t first_block, last_block, curr_block; |
| ext4_fsblk_t first_pblock, last_pblock; |
| }; |
| |
| static int finish_range(handle_t *handle, struct inode *inode, |
| struct migrate_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, 0); |
| |
| if (IS_ERR(path)) { |
| retval = PTR_ERR(path); |
| path = NULL; |
| 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_single_extent(inode, |
| lb->last_block - lb->first_block + 1, path); |
| |
| /* |
| * Make sure the credit we accumalated is not really high |
| */ |
| if (needed && ext4_handle_has_enough_credits(handle, |
| EXT4_RESERVE_TRANS_BLOCKS)) { |
| retval = ext4_journal_restart(handle, needed); |
| if (retval) |
| goto err_out; |
| } else if (needed) { |
| retval = ext4_journal_extend(handle, needed); |
| if (retval) { |
| /* |
| * 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, 0); |
| err_out: |
| if (path) { |
| ext4_ext_drop_refs(path); |
| kfree(path); |
| } |
| lb->first_pblock = 0; |
| return retval; |
| } |
| |
| static int update_extent_range(handle_t *handle, struct inode *inode, |
| ext4_fsblk_t pblock, struct migrate_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 == lb->curr_block)) { |
| lb->last_pblock = pblock; |
| lb->last_block = lb->curr_block; |
| lb->curr_block++; |
| 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 = lb->curr_block; |
| lb->curr_block++; |
| return retval; |
| } |
| |
| static int update_ind_extent_range(handle_t *handle, struct inode *inode, |
| ext4_fsblk_t pblock, |
| struct migrate_struct *lb) |
| { |
| struct buffer_head *bh; |
| __le32 *i_data; |
| int i, retval = 0; |
| unsigned long max_entries = inode->i_sb->s_blocksize >> 2; |
| |
| 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_extent_range(handle, inode, |
| le32_to_cpu(i_data[i]), lb); |
| if (retval) |
| break; |
| } else { |
| lb->curr_block++; |
| } |
| } |
| put_bh(bh); |
| return retval; |
| |
| } |
| |
| static int update_dind_extent_range(handle_t *handle, struct inode *inode, |
| ext4_fsblk_t pblock, |
| struct migrate_struct *lb) |
| { |
| struct buffer_head *bh; |
| __le32 *i_data; |
| int i, retval = 0; |
| unsigned long max_entries = inode->i_sb->s_blocksize >> 2; |
| |
| 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]), lb); |
| if (retval) |
| break; |
| } else { |
| /* Only update the file block number */ |
| lb->curr_block += max_entries; |
| } |
| } |
| put_bh(bh); |
| return retval; |
| |
| } |
| |
| static int update_tind_extent_range(handle_t *handle, struct inode *inode, |
| ext4_fsblk_t pblock, |
| struct migrate_struct *lb) |
| { |
| struct buffer_head *bh; |
| __le32 *i_data; |
| int i, retval = 0; |
| unsigned long max_entries = inode->i_sb->s_blocksize >> 2; |
| |
| 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]), lb); |
| if (retval) |
| break; |
| } else { |
| /* Only update the file block number */ |
| lb->curr_block += max_entries * max_entries; |
| } |
| } |
| put_bh(bh); |
| return retval; |
| |
| } |
| |
| static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode) |
| { |
| int retval = 0, needed; |
| |
| if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1)) |
| return 0; |
| /* |
| * We are freeing a blocks. During this we touch |
| * superblock, group descriptor and block bitmap. |
| * So allocate a credit of 3. We may update |
| * quota (user and group). |
| */ |
| needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb); |
| |
| if (ext4_journal_extend(handle, needed) != 0) |
| retval = ext4_journal_restart(handle, needed); |
| |
| 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]) { |
| extend_credit_for_blkdel(handle, inode); |
| ext4_free_blocks(handle, inode, NULL, |
| le32_to_cpu(tmp_idata[i]), 1, |
| EXT4_FREE_BLOCKS_METADATA | |
| EXT4_FREE_BLOCKS_FORGET); |
| } |
| } |
| put_bh(bh); |
| extend_credit_for_blkdel(handle, inode); |
| ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1, |
| EXT4_FREE_BLOCKS_METADATA | |
| EXT4_FREE_BLOCKS_FORGET); |
| 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); |
| extend_credit_for_blkdel(handle, inode); |
| ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1, |
| EXT4_FREE_BLOCKS_METADATA | |
| EXT4_FREE_BLOCKS_FORGET); |
| return 0; |
| } |
| |
| static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data) |
| { |
| int retval; |
| |
| /* ei->i_data[EXT4_IND_BLOCK] */ |
| if (i_data[0]) { |
| extend_credit_for_blkdel(handle, inode); |
| ext4_free_blocks(handle, inode, NULL, |
| le32_to_cpu(i_data[0]), 1, |
| EXT4_FREE_BLOCKS_METADATA | |
| EXT4_FREE_BLOCKS_FORGET); |
| } |
| |
| /* ei->i_data[EXT4_DIND_BLOCK] */ |
| if (i_data[1]) { |
| retval = free_dind_blocks(handle, inode, i_data[1]); |
| if (retval) |
| return retval; |
| } |
| |
| /* ei->i_data[EXT4_TIND_BLOCK] */ |
| if (i_data[2]) { |
| retval = free_tind_blocks(handle, inode, i_data[2]); |
| 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; |
| __le32 i_data[3]; |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode); |
| |
| /* |
| * One credit accounted for writing the |
| * i_data field of the original inode |
| */ |
| retval = ext4_journal_extend(handle, 1); |
| if (retval) { |
| retval = ext4_journal_restart(handle, 1); |
| if (retval) |
| goto err_out; |
| } |
| |
| i_data[0] = ei->i_data[EXT4_IND_BLOCK]; |
| i_data[1] = ei->i_data[EXT4_DIND_BLOCK]; |
| i_data[2] = ei->i_data[EXT4_TIND_BLOCK]; |
| |
| down_write(&EXT4_I(inode)->i_data_sem); |
| /* |
| * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation |
| * happened after we started the migrate. We need to |
| * fail the migrate |
| */ |
| if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) { |
| retval = -EAGAIN; |
| up_write(&EXT4_I(inode)->i_data_sem); |
| goto err_out; |
| } else |
| ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE); |
| /* |
| * We have the extent map build with the tmp inode. |
| * Now copy the i_data across |
| */ |
| ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS); |
| 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); |
| up_write(&EXT4_I(inode)->i_data_sem); |
| |
| /* |
| * We mark the inode dirty after, because we decrement the |
| * i_blocks when freeing the indirect meta-data blocks |
| */ |
| retval = free_ind_block(handle, inode, i_data); |
| 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 = ext4_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); |
| extend_credit_for_blkdel(handle, inode); |
| ext4_free_blocks(handle, inode, NULL, block, 1, |
| EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET); |
| 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) |
| { |
| handle_t *handle; |
| int retval = 0, i; |
| __le32 *i_data; |
| struct ext4_inode_info *ei; |
| struct inode *tmp_inode = NULL; |
| struct migrate_struct lb; |
| unsigned long max_entries; |
| __u32 goal; |
| uid_t owner[2]; |
| |
| /* |
| * If the filesystem does not support extents, or the inode |
| * already is extent-based, error out. |
| */ |
| if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb, |
| EXT4_FEATURE_INCOMPAT_EXTENTS) || |
| (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
| return -EINVAL; |
| |
| if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0) |
| /* |
| * don't migrate fast symlink |
| */ |
| return retval; |
| |
| /* |
| * Worst case we can touch the allocation bitmaps, a bgd |
| * block, and a block to link in the orphan list. We do need |
| * need to worry about credits for modifying the quota inode. |
| */ |
| handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, |
| 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb)); |
| |
| if (IS_ERR(handle)) { |
| retval = PTR_ERR(handle); |
| return retval; |
| } |
| goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) * |
| EXT4_INODES_PER_GROUP(inode->i_sb)) + 1; |
| owner[0] = i_uid_read(inode); |
| owner[1] = i_gid_read(inode); |
| tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode, |
| S_IFREG, NULL, goal, owner); |
| if (IS_ERR(tmp_inode)) { |
| retval = PTR_ERR(tmp_inode); |
| ext4_journal_stop(handle); |
| return retval; |
| } |
| i_size_write(tmp_inode, i_size_read(inode)); |
| /* |
| * Set the i_nlink to zero so it will be deleted later |
| * when we drop inode reference. |
| */ |
| clear_nlink(tmp_inode); |
| |
| ext4_ext_tree_init(handle, tmp_inode); |
| ext4_orphan_add(handle, tmp_inode); |
| ext4_journal_stop(handle); |
| |
| /* |
| * start with one credit accounted for |
| * superblock modification. |
| * |
| * For the tmp_inode we already have committed the |
| * transaction that created the inode. Later as and |
| * when we add extents we extent the journal |
| */ |
| /* |
| * Even though we take i_mutex we can still cause block |
| * allocation via mmap write to holes. If we have allocated |
| * new blocks we fail migrate. New block allocation will |
| * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated |
| * with i_data_sem held to prevent racing with block |
| * allocation. |
| */ |
| down_read((&EXT4_I(inode)->i_data_sem)); |
| ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE); |
| up_read((&EXT4_I(inode)->i_data_sem)); |
| |
| handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1); |
| if (IS_ERR(handle)) { |
| /* |
| * It is impossible to update on-disk structures without |
| * a handle, so just rollback in-core changes and live other |
| * work to orphan_list_cleanup() |
| */ |
| ext4_orphan_del(NULL, tmp_inode); |
| retval = PTR_ERR(handle); |
| goto out; |
| } |
| |
| 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; |
| for (i = 0; i < EXT4_NDIR_BLOCKS; i++) { |
| if (i_data[i]) { |
| retval = update_extent_range(handle, tmp_inode, |
| le32_to_cpu(i_data[i]), &lb); |
| if (retval) |
| goto err_out; |
| } else |
| lb.curr_block++; |
| } |
| if (i_data[EXT4_IND_BLOCK]) { |
| retval = update_ind_extent_range(handle, tmp_inode, |
| le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb); |
| if (retval) |
| goto err_out; |
| } else |
| lb.curr_block += max_entries; |
| if (i_data[EXT4_DIND_BLOCK]) { |
| retval = update_dind_extent_range(handle, tmp_inode, |
| le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb); |
| if (retval) |
| goto err_out; |
| } else |
| lb.curr_block += 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]), &lb); |
| if (retval) |
| goto err_out; |
| } |
| /* |
| * Build the last extent |
| */ |
| retval = finish_range(handle, tmp_inode, &lb); |
| err_out: |
| 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); |
| if (retval) |
| /* |
| * if we fail to swap inode data free the extent |
| * details of the tmp inode |
| */ |
| free_ext_block(handle, tmp_inode); |
| } |
| |
| /* We mark the tmp_inode dirty via ext4_ext_tree_init. */ |
| if (ext4_journal_extend(handle, 1) != 0) |
| ext4_journal_restart(handle, 1); |
| |
| /* |
| * 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); |
| ext4_journal_stop(handle); |
| out: |
| unlock_new_inode(tmp_inode); |
| iput(tmp_inode); |
| |
| return retval; |
| } |
| |
| /* |
| * Migrate a simple extent-based inode to use the i_blocks[] array |
| */ |
| int ext4_ind_migrate(struct inode *inode) |
| { |
| struct ext4_extent_header *eh; |
| struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es; |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| struct ext4_extent *ex; |
| unsigned int i, len; |
| ext4_fsblk_t blk; |
| handle_t *handle; |
| int ret; |
| |
| if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb, |
| EXT4_FEATURE_INCOMPAT_EXTENTS) || |
| (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
| return -EINVAL; |
| |
| if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, |
| EXT4_FEATURE_RO_COMPAT_BIGALLOC)) |
| return -EOPNOTSUPP; |
| |
| handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1); |
| if (IS_ERR(handle)) |
| return PTR_ERR(handle); |
| |
| down_write(&EXT4_I(inode)->i_data_sem); |
| ret = ext4_ext_check_inode(inode); |
| if (ret) |
| goto errout; |
| |
| eh = ext_inode_hdr(inode); |
| ex = EXT_FIRST_EXTENT(eh); |
| if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS || |
| eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) { |
| ret = -EOPNOTSUPP; |
| goto errout; |
| } |
| if (eh->eh_entries == 0) |
| blk = len = 0; |
| else { |
| len = le16_to_cpu(ex->ee_len); |
| blk = ext4_ext_pblock(ex); |
| if (len > EXT4_NDIR_BLOCKS) { |
| ret = -EOPNOTSUPP; |
| goto errout; |
| } |
| } |
| |
| ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); |
| memset(ei->i_data, 0, sizeof(ei->i_data)); |
| for (i=0; i < len; i++) |
| ei->i_data[i] = cpu_to_le32(blk++); |
| ext4_mark_inode_dirty(handle, inode); |
| errout: |
| ext4_journal_stop(handle); |
| up_write(&EXT4_I(inode)->i_data_sem); |
| return ret; |
| } |