cregit-Linux how code gets into the kernel

Release 4.10 fs/ext4/migrate.c

Directory: fs/ext4
/*
 * 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); /* Locking only for convinience since we are operating on temp inode */ down_write(&EXT4_I(inode)->i_data_sem); path = ext4_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)) { up_write((&EXT4_I(inode)->i_data_sem)); retval = ext4_journal_restart(handle, needed); down_write((&EXT4_I(inode)->i_data_sem)); 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 */ up_write((&EXT4_I(inode)->i_data_sem)); retval = ext4_journal_restart(handle, needed); down_write((&EXT4_I(inode)->i_data_sem)); if (retval) goto err_out; } } retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0); err_out: up_write((&EXT4_I(inode)->i_data_sem)); ext4_ext_drop_refs(path); kfree(path); lb->first_pblock = 0; return retval; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar22969.82%327.27%
dmitriy monakhovdmitriy monakhov7823.78%218.18%
mingming caomingming cao133.96%218.18%
theodore tsotheodore tso41.22%327.27%
frank mayharfrank mayhar41.22%19.09%
Total328100.00%11100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar10183.47%150.00%
dmitriy monakhovdmitriy monakhov2016.53%150.00%
Total121100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar13693.79%150.00%
dmitriy monakhovdmitriy monakhov96.21%150.00%
Total145100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar14397.28%150.00%
dmitriy monakhovdmitriy monakhov42.72%150.00%
Total147100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar14395.97%150.00%
dmitriy monakhovdmitriy monakhov64.03%150.00%
Total149100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar6490.14%133.33%
frank mayharfrank mayhar68.45%133.33%
dmitriy monakhovdmitriy monakhov11.41%133.33%
Total71100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar15292.68%240.00%
theodore tsotheodore tso84.88%120.00%
alex tomasalex tomas21.22%120.00%
peter huewepeter huewe21.22%120.00%
Total164100.00%5100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar16096.39%240.00%
theodore tsotheodore tso42.41%120.00%
alex tomasalex tomas10.60%120.00%
peter huewepeter huewe10.60%120.00%
Total166100.00%5100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar12195.28%240.00%
theodore tsotheodore tso43.15%120.00%
peter huewepeter huewe10.79%120.00%
alex tomasalex tomas10.79%120.00%
Total127100.00%5100.00%


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 original 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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar23893.70%337.50%
theodore tsotheodore tso155.91%450.00%
adam buchbinderadam buchbinder10.39%112.50%
Total254100.00%8100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar15995.78%233.33%
theodore tsotheodore tso53.01%233.33%
peter huewepeter huewe10.60%116.67%
alex tomasalex tomas10.60%116.67%
Total166100.00%6100.00%

/* * 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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar114100.00%1100.00%
Total114100.00%1100.00%


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_feature_extents(inode->i_sb) || (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, d_inode(inode->i_sb->s_root), 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_evict_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; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar50975.74%416.00%
dmitriy monakhovdmitriy monakhov7110.57%416.00%
andreas dilgerandreas dilger355.21%14.00%
valerie clementvalerie clement192.83%14.00%
theodore tsotheodore tso152.23%624.00%
dan carpenterdan carpenter71.04%28.00%
eric w. biedermaneric w. biederman60.89%14.00%
miklos szeredimiklos szeredi30.45%14.00%
david howellsdavid howells30.45%14.00%
anatol pomozovanatol pomozov10.15%14.00%
eric pariseric paris10.15%14.00%
wang shilongwang shilong10.15%14.00%
darrick j. wongdarrick j. wong10.15%14.00%
Total672100.00%25100.00%

/* * 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_lblk_t start, end; ext4_fsblk_t blk; handle_t *handle; int ret; if (!ext4_has_feature_extents(inode->i_sb) || (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) return -EINVAL; if (ext4_has_feature_bigalloc(inode->i_sb)) return -EOPNOTSUPP; /* * In order to get correct extent info, force all delayed allocation * blocks to be allocated, otherwise delayed allocation blocks may not * be reflected and bypass the checks on extent header. */ if (test_opt(inode->i_sb, DELALLOC)) ext4_alloc_da_blocks(inode); 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 = start = end = 0; else { len = le16_to_cpu(ex->ee_len); blk = ext4_ext_pblock(ex); start = le32_to_cpu(ex->ee_block); end = start + len - 1; if (end >= 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 = start; i <= end; 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; }

Contributors

PersonTokensPropCommitsCommitProp
lukas czernerlukas czerner31386.23%240.00%
eryu guaneryu guan4813.22%240.00%
darrick j. wongdarrick j. wong20.55%120.00%
Total363100.00%5100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar228875.84%510.42%
lukas czernerlukas czerner31410.41%24.17%
dmitriy monakhovdmitriy monakhov1926.36%612.50%
theodore tsotheodore tso581.92%1429.17%
eryu guaneryu guan481.59%24.17%
andreas dilgerandreas dilger351.16%12.08%
valerie clementvalerie clement190.63%12.08%
mingming caomingming cao130.43%24.17%
frank mayharfrank mayhar100.33%12.08%
dan carpenterdan carpenter70.23%24.17%
eric w. biedermaneric w. biederman60.20%12.08%
peter huewepeter huewe50.17%12.08%
alex tomasalex tomas50.17%12.08%
david howellsdavid howells30.10%12.08%
darrick j. wongdarrick j. wong30.10%12.08%
tejun heotejun heo30.10%12.08%
miklos szeredimiklos szeredi30.10%12.08%
eric pariseric paris10.03%12.08%
wang shilongwang shilong10.03%12.08%
adam buchbinderadam buchbinder10.03%12.08%
anatol pomozovanatol pomozov10.03%12.08%
christoph hellwigchristoph hellwig10.03%12.08%
Total3017100.00%48100.00%
Directory: fs/ext4
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