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2483 lines
70 KiB
2483 lines
70 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Copyright (C) 2007 Oracle. All rights reserved. |
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*/ |
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|
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#include <linux/fs.h> |
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#include <linux/slab.h> |
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#include <linux/sched.h> |
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#include <linux/writeback.h> |
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#include <linux/pagemap.h> |
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#include <linux/blkdev.h> |
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#include <linux/uuid.h> |
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#include "misc.h" |
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#include "ctree.h" |
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#include "disk-io.h" |
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#include "transaction.h" |
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#include "locking.h" |
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#include "tree-log.h" |
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#include "volumes.h" |
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#include "dev-replace.h" |
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#include "qgroup.h" |
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#include "block-group.h" |
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#include "space-info.h" |
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#include "zoned.h" |
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|
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#define BTRFS_ROOT_TRANS_TAG 0 |
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|
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/* |
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* Transaction states and transitions |
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* |
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* No running transaction (fs tree blocks are not modified) |
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* | |
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* | To next stage: |
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* | Call start_transaction() variants. Except btrfs_join_transaction_nostart(). |
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* V |
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* Transaction N [[TRANS_STATE_RUNNING]] |
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* | |
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* | New trans handles can be attached to transaction N by calling all |
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* | start_transaction() variants. |
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* | |
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* | To next stage: |
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* | Call btrfs_commit_transaction() on any trans handle attached to |
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* | transaction N |
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* V |
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* Transaction N [[TRANS_STATE_COMMIT_START]] |
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* | |
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* | Will wait for previous running transaction to completely finish if there |
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* | is one |
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* | |
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* | Then one of the following happes: |
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* | - Wait for all other trans handle holders to release. |
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* | The btrfs_commit_transaction() caller will do the commit work. |
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* | - Wait for current transaction to be committed by others. |
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* | Other btrfs_commit_transaction() caller will do the commit work. |
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* | |
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* | At this stage, only btrfs_join_transaction*() variants can attach |
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* | to this running transaction. |
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* | All other variants will wait for current one to finish and attach to |
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* | transaction N+1. |
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* | |
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* | To next stage: |
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* | Caller is chosen to commit transaction N, and all other trans handle |
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* | haven been released. |
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* V |
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* Transaction N [[TRANS_STATE_COMMIT_DOING]] |
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* | |
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* | The heavy lifting transaction work is started. |
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* | From running delayed refs (modifying extent tree) to creating pending |
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* | snapshots, running qgroups. |
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* | In short, modify supporting trees to reflect modifications of subvolume |
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* | trees. |
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* | |
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* | At this stage, all start_transaction() calls will wait for this |
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* | transaction to finish and attach to transaction N+1. |
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* | |
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* | To next stage: |
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* | Until all supporting trees are updated. |
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* V |
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* Transaction N [[TRANS_STATE_UNBLOCKED]] |
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* | Transaction N+1 |
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* | All needed trees are modified, thus we only [[TRANS_STATE_RUNNING]] |
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* | need to write them back to disk and update | |
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* | super blocks. | |
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* | | |
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* | At this stage, new transaction is allowed to | |
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* | start. | |
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* | All new start_transaction() calls will be | |
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* | attached to transid N+1. | |
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* | | |
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* | To next stage: | |
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* | Until all tree blocks are super blocks are | |
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* | written to block devices | |
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* V | |
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* Transaction N [[TRANS_STATE_COMPLETED]] V |
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* All tree blocks and super blocks are written. Transaction N+1 |
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* This transaction is finished and all its [[TRANS_STATE_COMMIT_START]] |
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* data structures will be cleaned up. | Life goes on |
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*/ |
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static const unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = { |
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[TRANS_STATE_RUNNING] = 0U, |
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[TRANS_STATE_COMMIT_START] = (__TRANS_START | __TRANS_ATTACH), |
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[TRANS_STATE_COMMIT_DOING] = (__TRANS_START | |
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__TRANS_ATTACH | |
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__TRANS_JOIN | |
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__TRANS_JOIN_NOSTART), |
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[TRANS_STATE_UNBLOCKED] = (__TRANS_START | |
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__TRANS_ATTACH | |
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__TRANS_JOIN | |
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__TRANS_JOIN_NOLOCK | |
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__TRANS_JOIN_NOSTART), |
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[TRANS_STATE_SUPER_COMMITTED] = (__TRANS_START | |
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__TRANS_ATTACH | |
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__TRANS_JOIN | |
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__TRANS_JOIN_NOLOCK | |
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__TRANS_JOIN_NOSTART), |
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[TRANS_STATE_COMPLETED] = (__TRANS_START | |
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__TRANS_ATTACH | |
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__TRANS_JOIN | |
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__TRANS_JOIN_NOLOCK | |
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__TRANS_JOIN_NOSTART), |
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}; |
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|
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void btrfs_put_transaction(struct btrfs_transaction *transaction) |
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{ |
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WARN_ON(refcount_read(&transaction->use_count) == 0); |
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if (refcount_dec_and_test(&transaction->use_count)) { |
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BUG_ON(!list_empty(&transaction->list)); |
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WARN_ON(!RB_EMPTY_ROOT( |
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&transaction->delayed_refs.href_root.rb_root)); |
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WARN_ON(!RB_EMPTY_ROOT( |
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&transaction->delayed_refs.dirty_extent_root)); |
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if (transaction->delayed_refs.pending_csums) |
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btrfs_err(transaction->fs_info, |
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"pending csums is %llu", |
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transaction->delayed_refs.pending_csums); |
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/* |
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* If any block groups are found in ->deleted_bgs then it's |
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* because the transaction was aborted and a commit did not |
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* happen (things failed before writing the new superblock |
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* and calling btrfs_finish_extent_commit()), so we can not |
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* discard the physical locations of the block groups. |
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*/ |
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while (!list_empty(&transaction->deleted_bgs)) { |
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struct btrfs_block_group *cache; |
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|
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cache = list_first_entry(&transaction->deleted_bgs, |
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struct btrfs_block_group, |
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bg_list); |
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list_del_init(&cache->bg_list); |
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btrfs_unfreeze_block_group(cache); |
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btrfs_put_block_group(cache); |
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} |
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WARN_ON(!list_empty(&transaction->dev_update_list)); |
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kfree(transaction); |
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} |
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} |
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static noinline void switch_commit_roots(struct btrfs_trans_handle *trans) |
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{ |
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struct btrfs_transaction *cur_trans = trans->transaction; |
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struct btrfs_fs_info *fs_info = trans->fs_info; |
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struct btrfs_root *root, *tmp; |
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struct btrfs_caching_control *caching_ctl, *next; |
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|
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down_write(&fs_info->commit_root_sem); |
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list_for_each_entry_safe(root, tmp, &cur_trans->switch_commits, |
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dirty_list) { |
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list_del_init(&root->dirty_list); |
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free_extent_buffer(root->commit_root); |
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root->commit_root = btrfs_root_node(root); |
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extent_io_tree_release(&root->dirty_log_pages); |
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btrfs_qgroup_clean_swapped_blocks(root); |
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} |
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|
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/* We can free old roots now. */ |
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spin_lock(&cur_trans->dropped_roots_lock); |
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while (!list_empty(&cur_trans->dropped_roots)) { |
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root = list_first_entry(&cur_trans->dropped_roots, |
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struct btrfs_root, root_list); |
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list_del_init(&root->root_list); |
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spin_unlock(&cur_trans->dropped_roots_lock); |
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btrfs_free_log(trans, root); |
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btrfs_drop_and_free_fs_root(fs_info, root); |
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spin_lock(&cur_trans->dropped_roots_lock); |
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} |
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spin_unlock(&cur_trans->dropped_roots_lock); |
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|
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/* |
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* We have to update the last_byte_to_unpin under the commit_root_sem, |
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* at the same time we swap out the commit roots. |
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* |
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* This is because we must have a real view of the last spot the caching |
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* kthreads were while caching. Consider the following views of the |
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* extent tree for a block group |
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* |
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* commit root |
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* +----+----+----+----+----+----+----+ |
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* |\\\\| |\\\\|\\\\| |\\\\|\\\\| |
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* +----+----+----+----+----+----+----+ |
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* 0 1 2 3 4 5 6 7 |
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* |
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* new commit root |
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* +----+----+----+----+----+----+----+ |
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* | | | |\\\\| | |\\\\| |
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* +----+----+----+----+----+----+----+ |
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* 0 1 2 3 4 5 6 7 |
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* |
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* If the cache_ctl->progress was at 3, then we are only allowed to |
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* unpin [0,1) and [2,3], because the caching thread has already |
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* processed those extents. We are not allowed to unpin [5,6), because |
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* the caching thread will re-start it's search from 3, and thus find |
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* the hole from [4,6) to add to the free space cache. |
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*/ |
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spin_lock(&fs_info->block_group_cache_lock); |
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list_for_each_entry_safe(caching_ctl, next, |
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&fs_info->caching_block_groups, list) { |
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struct btrfs_block_group *cache = caching_ctl->block_group; |
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|
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if (btrfs_block_group_done(cache)) { |
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cache->last_byte_to_unpin = (u64)-1; |
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list_del_init(&caching_ctl->list); |
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btrfs_put_caching_control(caching_ctl); |
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} else { |
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cache->last_byte_to_unpin = caching_ctl->progress; |
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} |
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} |
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spin_unlock(&fs_info->block_group_cache_lock); |
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up_write(&fs_info->commit_root_sem); |
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} |
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static inline void extwriter_counter_inc(struct btrfs_transaction *trans, |
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unsigned int type) |
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{ |
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if (type & TRANS_EXTWRITERS) |
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atomic_inc(&trans->num_extwriters); |
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} |
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static inline void extwriter_counter_dec(struct btrfs_transaction *trans, |
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unsigned int type) |
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{ |
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if (type & TRANS_EXTWRITERS) |
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atomic_dec(&trans->num_extwriters); |
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} |
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static inline void extwriter_counter_init(struct btrfs_transaction *trans, |
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unsigned int type) |
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{ |
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atomic_set(&trans->num_extwriters, ((type & TRANS_EXTWRITERS) ? 1 : 0)); |
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} |
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static inline int extwriter_counter_read(struct btrfs_transaction *trans) |
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{ |
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return atomic_read(&trans->num_extwriters); |
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} |
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|
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/* |
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* To be called after doing the chunk btree updates right after allocating a new |
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* chunk (after btrfs_chunk_alloc_add_chunk_item() is called), when removing a |
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* chunk after all chunk btree updates and after finishing the second phase of |
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* chunk allocation (btrfs_create_pending_block_groups()) in case some block |
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* group had its chunk item insertion delayed to the second phase. |
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*/ |
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void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans) |
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{ |
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struct btrfs_fs_info *fs_info = trans->fs_info; |
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|
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if (!trans->chunk_bytes_reserved) |
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return; |
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btrfs_block_rsv_release(fs_info, &fs_info->chunk_block_rsv, |
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trans->chunk_bytes_reserved, NULL); |
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trans->chunk_bytes_reserved = 0; |
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} |
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|
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/* |
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* either allocate a new transaction or hop into the existing one |
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*/ |
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static noinline int join_transaction(struct btrfs_fs_info *fs_info, |
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unsigned int type) |
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{ |
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struct btrfs_transaction *cur_trans; |
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|
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spin_lock(&fs_info->trans_lock); |
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loop: |
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/* The file system has been taken offline. No new transactions. */ |
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if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) { |
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spin_unlock(&fs_info->trans_lock); |
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return -EROFS; |
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} |
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|
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cur_trans = fs_info->running_transaction; |
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if (cur_trans) { |
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if (TRANS_ABORTED(cur_trans)) { |
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spin_unlock(&fs_info->trans_lock); |
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return cur_trans->aborted; |
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} |
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if (btrfs_blocked_trans_types[cur_trans->state] & type) { |
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spin_unlock(&fs_info->trans_lock); |
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return -EBUSY; |
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} |
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refcount_inc(&cur_trans->use_count); |
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atomic_inc(&cur_trans->num_writers); |
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extwriter_counter_inc(cur_trans, type); |
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spin_unlock(&fs_info->trans_lock); |
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return 0; |
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} |
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spin_unlock(&fs_info->trans_lock); |
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|
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/* |
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* If we are ATTACH, we just want to catch the current transaction, |
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* and commit it. If there is no transaction, just return ENOENT. |
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*/ |
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if (type == TRANS_ATTACH) |
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return -ENOENT; |
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|
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/* |
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* JOIN_NOLOCK only happens during the transaction commit, so |
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* it is impossible that ->running_transaction is NULL |
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*/ |
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BUG_ON(type == TRANS_JOIN_NOLOCK); |
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|
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cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS); |
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if (!cur_trans) |
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return -ENOMEM; |
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|
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spin_lock(&fs_info->trans_lock); |
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if (fs_info->running_transaction) { |
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/* |
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* someone started a transaction after we unlocked. Make sure |
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* to redo the checks above |
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*/ |
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kfree(cur_trans); |
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goto loop; |
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} else if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) { |
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spin_unlock(&fs_info->trans_lock); |
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kfree(cur_trans); |
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return -EROFS; |
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} |
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|
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cur_trans->fs_info = fs_info; |
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atomic_set(&cur_trans->pending_ordered, 0); |
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init_waitqueue_head(&cur_trans->pending_wait); |
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atomic_set(&cur_trans->num_writers, 1); |
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extwriter_counter_init(cur_trans, type); |
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init_waitqueue_head(&cur_trans->writer_wait); |
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init_waitqueue_head(&cur_trans->commit_wait); |
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cur_trans->state = TRANS_STATE_RUNNING; |
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/* |
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* One for this trans handle, one so it will live on until we |
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* commit the transaction. |
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*/ |
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refcount_set(&cur_trans->use_count, 2); |
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cur_trans->flags = 0; |
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cur_trans->start_time = ktime_get_seconds(); |
|
|
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memset(&cur_trans->delayed_refs, 0, sizeof(cur_trans->delayed_refs)); |
|
|
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cur_trans->delayed_refs.href_root = RB_ROOT_CACHED; |
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cur_trans->delayed_refs.dirty_extent_root = RB_ROOT; |
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atomic_set(&cur_trans->delayed_refs.num_entries, 0); |
|
|
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/* |
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* although the tree mod log is per file system and not per transaction, |
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* the log must never go across transaction boundaries. |
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*/ |
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smp_mb(); |
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if (!list_empty(&fs_info->tree_mod_seq_list)) |
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WARN(1, KERN_ERR "BTRFS: tree_mod_seq_list not empty when creating a fresh transaction\n"); |
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if (!RB_EMPTY_ROOT(&fs_info->tree_mod_log)) |
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WARN(1, KERN_ERR "BTRFS: tree_mod_log rb tree not empty when creating a fresh transaction\n"); |
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atomic64_set(&fs_info->tree_mod_seq, 0); |
|
|
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spin_lock_init(&cur_trans->delayed_refs.lock); |
|
|
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INIT_LIST_HEAD(&cur_trans->pending_snapshots); |
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INIT_LIST_HEAD(&cur_trans->dev_update_list); |
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INIT_LIST_HEAD(&cur_trans->switch_commits); |
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INIT_LIST_HEAD(&cur_trans->dirty_bgs); |
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INIT_LIST_HEAD(&cur_trans->io_bgs); |
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INIT_LIST_HEAD(&cur_trans->dropped_roots); |
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mutex_init(&cur_trans->cache_write_mutex); |
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spin_lock_init(&cur_trans->dirty_bgs_lock); |
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INIT_LIST_HEAD(&cur_trans->deleted_bgs); |
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spin_lock_init(&cur_trans->dropped_roots_lock); |
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INIT_LIST_HEAD(&cur_trans->releasing_ebs); |
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spin_lock_init(&cur_trans->releasing_ebs_lock); |
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list_add_tail(&cur_trans->list, &fs_info->trans_list); |
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extent_io_tree_init(fs_info, &cur_trans->dirty_pages, |
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IO_TREE_TRANS_DIRTY_PAGES, fs_info->btree_inode); |
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extent_io_tree_init(fs_info, &cur_trans->pinned_extents, |
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IO_TREE_FS_PINNED_EXTENTS, NULL); |
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fs_info->generation++; |
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cur_trans->transid = fs_info->generation; |
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fs_info->running_transaction = cur_trans; |
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cur_trans->aborted = 0; |
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spin_unlock(&fs_info->trans_lock); |
|
|
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return 0; |
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} |
|
|
|
/* |
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* This does all the record keeping required to make sure that a shareable root |
|
* is properly recorded in a given transaction. This is required to make sure |
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* the old root from before we joined the transaction is deleted when the |
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* transaction commits. |
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*/ |
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static int record_root_in_trans(struct btrfs_trans_handle *trans, |
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struct btrfs_root *root, |
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int force) |
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{ |
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struct btrfs_fs_info *fs_info = root->fs_info; |
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int ret = 0; |
|
|
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if ((test_bit(BTRFS_ROOT_SHAREABLE, &root->state) && |
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root->last_trans < trans->transid) || force) { |
|
WARN_ON(root == fs_info->extent_root); |
|
WARN_ON(!force && root->commit_root != root->node); |
|
|
|
/* |
|
* see below for IN_TRANS_SETUP usage rules |
|
* we have the reloc mutex held now, so there |
|
* is only one writer in this function |
|
*/ |
|
set_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state); |
|
|
|
/* make sure readers find IN_TRANS_SETUP before |
|
* they find our root->last_trans update |
|
*/ |
|
smp_wmb(); |
|
|
|
spin_lock(&fs_info->fs_roots_radix_lock); |
|
if (root->last_trans == trans->transid && !force) { |
|
spin_unlock(&fs_info->fs_roots_radix_lock); |
|
return 0; |
|
} |
|
radix_tree_tag_set(&fs_info->fs_roots_radix, |
|
(unsigned long)root->root_key.objectid, |
|
BTRFS_ROOT_TRANS_TAG); |
|
spin_unlock(&fs_info->fs_roots_radix_lock); |
|
root->last_trans = trans->transid; |
|
|
|
/* this is pretty tricky. We don't want to |
|
* take the relocation lock in btrfs_record_root_in_trans |
|
* unless we're really doing the first setup for this root in |
|
* this transaction. |
|
* |
|
* Normally we'd use root->last_trans as a flag to decide |
|
* if we want to take the expensive mutex. |
|
* |
|
* But, we have to set root->last_trans before we |
|
* init the relocation root, otherwise, we trip over warnings |
|
* in ctree.c. The solution used here is to flag ourselves |
|
* with root IN_TRANS_SETUP. When this is 1, we're still |
|
* fixing up the reloc trees and everyone must wait. |
|
* |
|
* When this is zero, they can trust root->last_trans and fly |
|
* through btrfs_record_root_in_trans without having to take the |
|
* lock. smp_wmb() makes sure that all the writes above are |
|
* done before we pop in the zero below |
|
*/ |
|
ret = btrfs_init_reloc_root(trans, root); |
|
smp_mb__before_atomic(); |
|
clear_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state); |
|
} |
|
return ret; |
|
} |
|
|
|
|
|
void btrfs_add_dropped_root(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_transaction *cur_trans = trans->transaction; |
|
|
|
/* Add ourselves to the transaction dropped list */ |
|
spin_lock(&cur_trans->dropped_roots_lock); |
|
list_add_tail(&root->root_list, &cur_trans->dropped_roots); |
|
spin_unlock(&cur_trans->dropped_roots_lock); |
|
|
|
/* Make sure we don't try to update the root at commit time */ |
|
spin_lock(&fs_info->fs_roots_radix_lock); |
|
radix_tree_tag_clear(&fs_info->fs_roots_radix, |
|
(unsigned long)root->root_key.objectid, |
|
BTRFS_ROOT_TRANS_TAG); |
|
spin_unlock(&fs_info->fs_roots_radix_lock); |
|
} |
|
|
|
int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
int ret; |
|
|
|
if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state)) |
|
return 0; |
|
|
|
/* |
|
* see record_root_in_trans for comments about IN_TRANS_SETUP usage |
|
* and barriers |
|
*/ |
|
smp_rmb(); |
|
if (root->last_trans == trans->transid && |
|
!test_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state)) |
|
return 0; |
|
|
|
mutex_lock(&fs_info->reloc_mutex); |
|
ret = record_root_in_trans(trans, root, 0); |
|
mutex_unlock(&fs_info->reloc_mutex); |
|
|
|
return ret; |
|
} |
|
|
|
static inline int is_transaction_blocked(struct btrfs_transaction *trans) |
|
{ |
|
return (trans->state >= TRANS_STATE_COMMIT_START && |
|
trans->state < TRANS_STATE_UNBLOCKED && |
|
!TRANS_ABORTED(trans)); |
|
} |
|
|
|
/* wait for commit against the current transaction to become unblocked |
|
* when this is done, it is safe to start a new transaction, but the current |
|
* transaction might not be fully on disk. |
|
*/ |
|
static void wait_current_trans(struct btrfs_fs_info *fs_info) |
|
{ |
|
struct btrfs_transaction *cur_trans; |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
cur_trans = fs_info->running_transaction; |
|
if (cur_trans && is_transaction_blocked(cur_trans)) { |
|
refcount_inc(&cur_trans->use_count); |
|
spin_unlock(&fs_info->trans_lock); |
|
|
|
wait_event(fs_info->transaction_wait, |
|
cur_trans->state >= TRANS_STATE_UNBLOCKED || |
|
TRANS_ABORTED(cur_trans)); |
|
btrfs_put_transaction(cur_trans); |
|
} else { |
|
spin_unlock(&fs_info->trans_lock); |
|
} |
|
} |
|
|
|
static int may_wait_transaction(struct btrfs_fs_info *fs_info, int type) |
|
{ |
|
if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) |
|
return 0; |
|
|
|
if (type == TRANS_START) |
|
return 1; |
|
|
|
return 0; |
|
} |
|
|
|
static inline bool need_reserve_reloc_root(struct btrfs_root *root) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
|
|
if (!fs_info->reloc_ctl || |
|
!test_bit(BTRFS_ROOT_SHAREABLE, &root->state) || |
|
root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID || |
|
root->reloc_root) |
|
return false; |
|
|
|
return true; |
|
} |
|
|
|
static struct btrfs_trans_handle * |
|
start_transaction(struct btrfs_root *root, unsigned int num_items, |
|
unsigned int type, enum btrfs_reserve_flush_enum flush, |
|
bool enforce_qgroups) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv; |
|
struct btrfs_trans_handle *h; |
|
struct btrfs_transaction *cur_trans; |
|
u64 num_bytes = 0; |
|
u64 qgroup_reserved = 0; |
|
bool reloc_reserved = false; |
|
bool do_chunk_alloc = false; |
|
int ret; |
|
|
|
if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) |
|
return ERR_PTR(-EROFS); |
|
|
|
if (current->journal_info) { |
|
WARN_ON(type & TRANS_EXTWRITERS); |
|
h = current->journal_info; |
|
refcount_inc(&h->use_count); |
|
WARN_ON(refcount_read(&h->use_count) > 2); |
|
h->orig_rsv = h->block_rsv; |
|
h->block_rsv = NULL; |
|
goto got_it; |
|
} |
|
|
|
/* |
|
* Do the reservation before we join the transaction so we can do all |
|
* the appropriate flushing if need be. |
|
*/ |
|
if (num_items && root != fs_info->chunk_root) { |
|
struct btrfs_block_rsv *rsv = &fs_info->trans_block_rsv; |
|
u64 delayed_refs_bytes = 0; |
|
|
|
qgroup_reserved = num_items * fs_info->nodesize; |
|
ret = btrfs_qgroup_reserve_meta_pertrans(root, qgroup_reserved, |
|
enforce_qgroups); |
|
if (ret) |
|
return ERR_PTR(ret); |
|
|
|
/* |
|
* We want to reserve all the bytes we may need all at once, so |
|
* we only do 1 enospc flushing cycle per transaction start. We |
|
* accomplish this by simply assuming we'll do 2 x num_items |
|
* worth of delayed refs updates in this trans handle, and |
|
* refill that amount for whatever is missing in the reserve. |
|
*/ |
|
num_bytes = btrfs_calc_insert_metadata_size(fs_info, num_items); |
|
if (flush == BTRFS_RESERVE_FLUSH_ALL && |
|
delayed_refs_rsv->full == 0) { |
|
delayed_refs_bytes = num_bytes; |
|
num_bytes <<= 1; |
|
} |
|
|
|
/* |
|
* Do the reservation for the relocation root creation |
|
*/ |
|
if (need_reserve_reloc_root(root)) { |
|
num_bytes += fs_info->nodesize; |
|
reloc_reserved = true; |
|
} |
|
|
|
ret = btrfs_block_rsv_add(root, rsv, num_bytes, flush); |
|
if (ret) |
|
goto reserve_fail; |
|
if (delayed_refs_bytes) { |
|
btrfs_migrate_to_delayed_refs_rsv(fs_info, rsv, |
|
delayed_refs_bytes); |
|
num_bytes -= delayed_refs_bytes; |
|
} |
|
|
|
if (rsv->space_info->force_alloc) |
|
do_chunk_alloc = true; |
|
} else if (num_items == 0 && flush == BTRFS_RESERVE_FLUSH_ALL && |
|
!delayed_refs_rsv->full) { |
|
/* |
|
* Some people call with btrfs_start_transaction(root, 0) |
|
* because they can be throttled, but have some other mechanism |
|
* for reserving space. We still want these guys to refill the |
|
* delayed block_rsv so just add 1 items worth of reservation |
|
* here. |
|
*/ |
|
ret = btrfs_delayed_refs_rsv_refill(fs_info, flush); |
|
if (ret) |
|
goto reserve_fail; |
|
} |
|
again: |
|
h = kmem_cache_zalloc(btrfs_trans_handle_cachep, GFP_NOFS); |
|
if (!h) { |
|
ret = -ENOMEM; |
|
goto alloc_fail; |
|
} |
|
|
|
/* |
|
* If we are JOIN_NOLOCK we're already committing a transaction and |
|
* waiting on this guy, so we don't need to do the sb_start_intwrite |
|
* because we're already holding a ref. We need this because we could |
|
* have raced in and did an fsync() on a file which can kick a commit |
|
* and then we deadlock with somebody doing a freeze. |
|
* |
|
* If we are ATTACH, it means we just want to catch the current |
|
* transaction and commit it, so we needn't do sb_start_intwrite(). |
|
*/ |
|
if (type & __TRANS_FREEZABLE) |
|
sb_start_intwrite(fs_info->sb); |
|
|
|
if (may_wait_transaction(fs_info, type)) |
|
wait_current_trans(fs_info); |
|
|
|
do { |
|
ret = join_transaction(fs_info, type); |
|
if (ret == -EBUSY) { |
|
wait_current_trans(fs_info); |
|
if (unlikely(type == TRANS_ATTACH || |
|
type == TRANS_JOIN_NOSTART)) |
|
ret = -ENOENT; |
|
} |
|
} while (ret == -EBUSY); |
|
|
|
if (ret < 0) |
|
goto join_fail; |
|
|
|
cur_trans = fs_info->running_transaction; |
|
|
|
h->transid = cur_trans->transid; |
|
h->transaction = cur_trans; |
|
h->root = root; |
|
refcount_set(&h->use_count, 1); |
|
h->fs_info = root->fs_info; |
|
|
|
h->type = type; |
|
INIT_LIST_HEAD(&h->new_bgs); |
|
|
|
smp_mb(); |
|
if (cur_trans->state >= TRANS_STATE_COMMIT_START && |
|
may_wait_transaction(fs_info, type)) { |
|
current->journal_info = h; |
|
btrfs_commit_transaction(h); |
|
goto again; |
|
} |
|
|
|
if (num_bytes) { |
|
trace_btrfs_space_reservation(fs_info, "transaction", |
|
h->transid, num_bytes, 1); |
|
h->block_rsv = &fs_info->trans_block_rsv; |
|
h->bytes_reserved = num_bytes; |
|
h->reloc_reserved = reloc_reserved; |
|
} |
|
|
|
got_it: |
|
if (!current->journal_info) |
|
current->journal_info = h; |
|
|
|
/* |
|
* If the space_info is marked ALLOC_FORCE then we'll get upgraded to |
|
* ALLOC_FORCE the first run through, and then we won't allocate for |
|
* anybody else who races in later. We don't care about the return |
|
* value here. |
|
*/ |
|
if (do_chunk_alloc && num_bytes) { |
|
u64 flags = h->block_rsv->space_info->flags; |
|
|
|
btrfs_chunk_alloc(h, btrfs_get_alloc_profile(fs_info, flags), |
|
CHUNK_ALLOC_NO_FORCE); |
|
} |
|
|
|
/* |
|
* btrfs_record_root_in_trans() needs to alloc new extents, and may |
|
* call btrfs_join_transaction() while we're also starting a |
|
* transaction. |
|
* |
|
* Thus it need to be called after current->journal_info initialized, |
|
* or we can deadlock. |
|
*/ |
|
ret = btrfs_record_root_in_trans(h, root); |
|
if (ret) { |
|
/* |
|
* The transaction handle is fully initialized and linked with |
|
* other structures so it needs to be ended in case of errors, |
|
* not just freed. |
|
*/ |
|
btrfs_end_transaction(h); |
|
return ERR_PTR(ret); |
|
} |
|
|
|
return h; |
|
|
|
join_fail: |
|
if (type & __TRANS_FREEZABLE) |
|
sb_end_intwrite(fs_info->sb); |
|
kmem_cache_free(btrfs_trans_handle_cachep, h); |
|
alloc_fail: |
|
if (num_bytes) |
|
btrfs_block_rsv_release(fs_info, &fs_info->trans_block_rsv, |
|
num_bytes, NULL); |
|
reserve_fail: |
|
btrfs_qgroup_free_meta_pertrans(root, qgroup_reserved); |
|
return ERR_PTR(ret); |
|
} |
|
|
|
struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, |
|
unsigned int num_items) |
|
{ |
|
return start_transaction(root, num_items, TRANS_START, |
|
BTRFS_RESERVE_FLUSH_ALL, true); |
|
} |
|
|
|
struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv( |
|
struct btrfs_root *root, |
|
unsigned int num_items) |
|
{ |
|
return start_transaction(root, num_items, TRANS_START, |
|
BTRFS_RESERVE_FLUSH_ALL_STEAL, false); |
|
} |
|
|
|
struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root) |
|
{ |
|
return start_transaction(root, 0, TRANS_JOIN, BTRFS_RESERVE_NO_FLUSH, |
|
true); |
|
} |
|
|
|
struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root) |
|
{ |
|
return start_transaction(root, 0, TRANS_JOIN_NOLOCK, |
|
BTRFS_RESERVE_NO_FLUSH, true); |
|
} |
|
|
|
/* |
|
* Similar to regular join but it never starts a transaction when none is |
|
* running or after waiting for the current one to finish. |
|
*/ |
|
struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root) |
|
{ |
|
return start_transaction(root, 0, TRANS_JOIN_NOSTART, |
|
BTRFS_RESERVE_NO_FLUSH, true); |
|
} |
|
|
|
/* |
|
* btrfs_attach_transaction() - catch the running transaction |
|
* |
|
* It is used when we want to commit the current the transaction, but |
|
* don't want to start a new one. |
|
* |
|
* Note: If this function return -ENOENT, it just means there is no |
|
* running transaction. But it is possible that the inactive transaction |
|
* is still in the memory, not fully on disk. If you hope there is no |
|
* inactive transaction in the fs when -ENOENT is returned, you should |
|
* invoke |
|
* btrfs_attach_transaction_barrier() |
|
*/ |
|
struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root) |
|
{ |
|
return start_transaction(root, 0, TRANS_ATTACH, |
|
BTRFS_RESERVE_NO_FLUSH, true); |
|
} |
|
|
|
/* |
|
* btrfs_attach_transaction_barrier() - catch the running transaction |
|
* |
|
* It is similar to the above function, the difference is this one |
|
* will wait for all the inactive transactions until they fully |
|
* complete. |
|
*/ |
|
struct btrfs_trans_handle * |
|
btrfs_attach_transaction_barrier(struct btrfs_root *root) |
|
{ |
|
struct btrfs_trans_handle *trans; |
|
|
|
trans = start_transaction(root, 0, TRANS_ATTACH, |
|
BTRFS_RESERVE_NO_FLUSH, true); |
|
if (trans == ERR_PTR(-ENOENT)) |
|
btrfs_wait_for_commit(root->fs_info, 0); |
|
|
|
return trans; |
|
} |
|
|
|
/* Wait for a transaction commit to reach at least the given state. */ |
|
static noinline void wait_for_commit(struct btrfs_transaction *commit, |
|
const enum btrfs_trans_state min_state) |
|
{ |
|
wait_event(commit->commit_wait, commit->state >= min_state); |
|
} |
|
|
|
int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid) |
|
{ |
|
struct btrfs_transaction *cur_trans = NULL, *t; |
|
int ret = 0; |
|
|
|
if (transid) { |
|
if (transid <= fs_info->last_trans_committed) |
|
goto out; |
|
|
|
/* find specified transaction */ |
|
spin_lock(&fs_info->trans_lock); |
|
list_for_each_entry(t, &fs_info->trans_list, list) { |
|
if (t->transid == transid) { |
|
cur_trans = t; |
|
refcount_inc(&cur_trans->use_count); |
|
ret = 0; |
|
break; |
|
} |
|
if (t->transid > transid) { |
|
ret = 0; |
|
break; |
|
} |
|
} |
|
spin_unlock(&fs_info->trans_lock); |
|
|
|
/* |
|
* The specified transaction doesn't exist, or we |
|
* raced with btrfs_commit_transaction |
|
*/ |
|
if (!cur_trans) { |
|
if (transid > fs_info->last_trans_committed) |
|
ret = -EINVAL; |
|
goto out; |
|
} |
|
} else { |
|
/* find newest transaction that is committing | committed */ |
|
spin_lock(&fs_info->trans_lock); |
|
list_for_each_entry_reverse(t, &fs_info->trans_list, |
|
list) { |
|
if (t->state >= TRANS_STATE_COMMIT_START) { |
|
if (t->state == TRANS_STATE_COMPLETED) |
|
break; |
|
cur_trans = t; |
|
refcount_inc(&cur_trans->use_count); |
|
break; |
|
} |
|
} |
|
spin_unlock(&fs_info->trans_lock); |
|
if (!cur_trans) |
|
goto out; /* nothing committing|committed */ |
|
} |
|
|
|
wait_for_commit(cur_trans, TRANS_STATE_COMPLETED); |
|
btrfs_put_transaction(cur_trans); |
|
out: |
|
return ret; |
|
} |
|
|
|
void btrfs_throttle(struct btrfs_fs_info *fs_info) |
|
{ |
|
wait_current_trans(fs_info); |
|
} |
|
|
|
static bool should_end_transaction(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
|
|
if (btrfs_check_space_for_delayed_refs(fs_info)) |
|
return true; |
|
|
|
return !!btrfs_block_rsv_check(&fs_info->global_block_rsv, 5); |
|
} |
|
|
|
bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_transaction *cur_trans = trans->transaction; |
|
|
|
if (cur_trans->state >= TRANS_STATE_COMMIT_START || |
|
test_bit(BTRFS_DELAYED_REFS_FLUSHING, &cur_trans->delayed_refs.flags)) |
|
return true; |
|
|
|
return should_end_transaction(trans); |
|
} |
|
|
|
static void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans) |
|
|
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
|
|
if (!trans->block_rsv) { |
|
ASSERT(!trans->bytes_reserved); |
|
return; |
|
} |
|
|
|
if (!trans->bytes_reserved) |
|
return; |
|
|
|
ASSERT(trans->block_rsv == &fs_info->trans_block_rsv); |
|
trace_btrfs_space_reservation(fs_info, "transaction", |
|
trans->transid, trans->bytes_reserved, 0); |
|
btrfs_block_rsv_release(fs_info, trans->block_rsv, |
|
trans->bytes_reserved, NULL); |
|
trans->bytes_reserved = 0; |
|
} |
|
|
|
static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, |
|
int throttle) |
|
{ |
|
struct btrfs_fs_info *info = trans->fs_info; |
|
struct btrfs_transaction *cur_trans = trans->transaction; |
|
int err = 0; |
|
|
|
if (refcount_read(&trans->use_count) > 1) { |
|
refcount_dec(&trans->use_count); |
|
trans->block_rsv = trans->orig_rsv; |
|
return 0; |
|
} |
|
|
|
btrfs_trans_release_metadata(trans); |
|
trans->block_rsv = NULL; |
|
|
|
btrfs_create_pending_block_groups(trans); |
|
|
|
btrfs_trans_release_chunk_metadata(trans); |
|
|
|
if (trans->type & __TRANS_FREEZABLE) |
|
sb_end_intwrite(info->sb); |
|
|
|
WARN_ON(cur_trans != info->running_transaction); |
|
WARN_ON(atomic_read(&cur_trans->num_writers) < 1); |
|
atomic_dec(&cur_trans->num_writers); |
|
extwriter_counter_dec(cur_trans, trans->type); |
|
|
|
cond_wake_up(&cur_trans->writer_wait); |
|
btrfs_put_transaction(cur_trans); |
|
|
|
if (current->journal_info == trans) |
|
current->journal_info = NULL; |
|
|
|
if (throttle) |
|
btrfs_run_delayed_iputs(info); |
|
|
|
if (TRANS_ABORTED(trans) || |
|
test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) { |
|
wake_up_process(info->transaction_kthread); |
|
if (TRANS_ABORTED(trans)) |
|
err = trans->aborted; |
|
else |
|
err = -EROFS; |
|
} |
|
|
|
kmem_cache_free(btrfs_trans_handle_cachep, trans); |
|
return err; |
|
} |
|
|
|
int btrfs_end_transaction(struct btrfs_trans_handle *trans) |
|
{ |
|
return __btrfs_end_transaction(trans, 0); |
|
} |
|
|
|
int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans) |
|
{ |
|
return __btrfs_end_transaction(trans, 1); |
|
} |
|
|
|
/* |
|
* when btree blocks are allocated, they have some corresponding bits set for |
|
* them in one of two extent_io trees. This is used to make sure all of |
|
* those extents are sent to disk but does not wait on them |
|
*/ |
|
int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info, |
|
struct extent_io_tree *dirty_pages, int mark) |
|
{ |
|
int err = 0; |
|
int werr = 0; |
|
struct address_space *mapping = fs_info->btree_inode->i_mapping; |
|
struct extent_state *cached_state = NULL; |
|
u64 start = 0; |
|
u64 end; |
|
|
|
atomic_inc(&BTRFS_I(fs_info->btree_inode)->sync_writers); |
|
while (!find_first_extent_bit(dirty_pages, start, &start, &end, |
|
mark, &cached_state)) { |
|
bool wait_writeback = false; |
|
|
|
err = convert_extent_bit(dirty_pages, start, end, |
|
EXTENT_NEED_WAIT, |
|
mark, &cached_state); |
|
/* |
|
* convert_extent_bit can return -ENOMEM, which is most of the |
|
* time a temporary error. So when it happens, ignore the error |
|
* and wait for writeback of this range to finish - because we |
|
* failed to set the bit EXTENT_NEED_WAIT for the range, a call |
|
* to __btrfs_wait_marked_extents() would not know that |
|
* writeback for this range started and therefore wouldn't |
|
* wait for it to finish - we don't want to commit a |
|
* superblock that points to btree nodes/leafs for which |
|
* writeback hasn't finished yet (and without errors). |
|
* We cleanup any entries left in the io tree when committing |
|
* the transaction (through extent_io_tree_release()). |
|
*/ |
|
if (err == -ENOMEM) { |
|
err = 0; |
|
wait_writeback = true; |
|
} |
|
if (!err) |
|
err = filemap_fdatawrite_range(mapping, start, end); |
|
if (err) |
|
werr = err; |
|
else if (wait_writeback) |
|
werr = filemap_fdatawait_range(mapping, start, end); |
|
free_extent_state(cached_state); |
|
cached_state = NULL; |
|
cond_resched(); |
|
start = end + 1; |
|
} |
|
atomic_dec(&BTRFS_I(fs_info->btree_inode)->sync_writers); |
|
return werr; |
|
} |
|
|
|
/* |
|
* when btree blocks are allocated, they have some corresponding bits set for |
|
* them in one of two extent_io trees. This is used to make sure all of |
|
* those extents are on disk for transaction or log commit. We wait |
|
* on all the pages and clear them from the dirty pages state tree |
|
*/ |
|
static int __btrfs_wait_marked_extents(struct btrfs_fs_info *fs_info, |
|
struct extent_io_tree *dirty_pages) |
|
{ |
|
int err = 0; |
|
int werr = 0; |
|
struct address_space *mapping = fs_info->btree_inode->i_mapping; |
|
struct extent_state *cached_state = NULL; |
|
u64 start = 0; |
|
u64 end; |
|
|
|
while (!find_first_extent_bit(dirty_pages, start, &start, &end, |
|
EXTENT_NEED_WAIT, &cached_state)) { |
|
/* |
|
* Ignore -ENOMEM errors returned by clear_extent_bit(). |
|
* When committing the transaction, we'll remove any entries |
|
* left in the io tree. For a log commit, we don't remove them |
|
* after committing the log because the tree can be accessed |
|
* concurrently - we do it only at transaction commit time when |
|
* it's safe to do it (through extent_io_tree_release()). |
|
*/ |
|
err = clear_extent_bit(dirty_pages, start, end, |
|
EXTENT_NEED_WAIT, 0, 0, &cached_state); |
|
if (err == -ENOMEM) |
|
err = 0; |
|
if (!err) |
|
err = filemap_fdatawait_range(mapping, start, end); |
|
if (err) |
|
werr = err; |
|
free_extent_state(cached_state); |
|
cached_state = NULL; |
|
cond_resched(); |
|
start = end + 1; |
|
} |
|
if (err) |
|
werr = err; |
|
return werr; |
|
} |
|
|
|
static int btrfs_wait_extents(struct btrfs_fs_info *fs_info, |
|
struct extent_io_tree *dirty_pages) |
|
{ |
|
bool errors = false; |
|
int err; |
|
|
|
err = __btrfs_wait_marked_extents(fs_info, dirty_pages); |
|
if (test_and_clear_bit(BTRFS_FS_BTREE_ERR, &fs_info->flags)) |
|
errors = true; |
|
|
|
if (errors && !err) |
|
err = -EIO; |
|
return err; |
|
} |
|
|
|
int btrfs_wait_tree_log_extents(struct btrfs_root *log_root, int mark) |
|
{ |
|
struct btrfs_fs_info *fs_info = log_root->fs_info; |
|
struct extent_io_tree *dirty_pages = &log_root->dirty_log_pages; |
|
bool errors = false; |
|
int err; |
|
|
|
ASSERT(log_root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID); |
|
|
|
err = __btrfs_wait_marked_extents(fs_info, dirty_pages); |
|
if ((mark & EXTENT_DIRTY) && |
|
test_and_clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags)) |
|
errors = true; |
|
|
|
if ((mark & EXTENT_NEW) && |
|
test_and_clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags)) |
|
errors = true; |
|
|
|
if (errors && !err) |
|
err = -EIO; |
|
return err; |
|
} |
|
|
|
/* |
|
* When btree blocks are allocated the corresponding extents are marked dirty. |
|
* This function ensures such extents are persisted on disk for transaction or |
|
* log commit. |
|
* |
|
* @trans: transaction whose dirty pages we'd like to write |
|
*/ |
|
static int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans) |
|
{ |
|
int ret; |
|
int ret2; |
|
struct extent_io_tree *dirty_pages = &trans->transaction->dirty_pages; |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct blk_plug plug; |
|
|
|
blk_start_plug(&plug); |
|
ret = btrfs_write_marked_extents(fs_info, dirty_pages, EXTENT_DIRTY); |
|
blk_finish_plug(&plug); |
|
ret2 = btrfs_wait_extents(fs_info, dirty_pages); |
|
|
|
extent_io_tree_release(&trans->transaction->dirty_pages); |
|
|
|
if (ret) |
|
return ret; |
|
else if (ret2) |
|
return ret2; |
|
else |
|
return 0; |
|
} |
|
|
|
/* |
|
* this is used to update the root pointer in the tree of tree roots. |
|
* |
|
* But, in the case of the extent allocation tree, updating the root |
|
* pointer may allocate blocks which may change the root of the extent |
|
* allocation tree. |
|
* |
|
* So, this loops and repeats and makes sure the cowonly root didn't |
|
* change while the root pointer was being updated in the metadata. |
|
*/ |
|
static int update_cowonly_root(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root) |
|
{ |
|
int ret; |
|
u64 old_root_bytenr; |
|
u64 old_root_used; |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_root *tree_root = fs_info->tree_root; |
|
|
|
old_root_used = btrfs_root_used(&root->root_item); |
|
|
|
while (1) { |
|
old_root_bytenr = btrfs_root_bytenr(&root->root_item); |
|
if (old_root_bytenr == root->node->start && |
|
old_root_used == btrfs_root_used(&root->root_item)) |
|
break; |
|
|
|
btrfs_set_root_node(&root->root_item, root->node); |
|
ret = btrfs_update_root(trans, tree_root, |
|
&root->root_key, |
|
&root->root_item); |
|
if (ret) |
|
return ret; |
|
|
|
old_root_used = btrfs_root_used(&root->root_item); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* update all the cowonly tree roots on disk |
|
* |
|
* The error handling in this function may not be obvious. Any of the |
|
* failures will cause the file system to go offline. We still need |
|
* to clean up the delayed refs. |
|
*/ |
|
static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct list_head *dirty_bgs = &trans->transaction->dirty_bgs; |
|
struct list_head *io_bgs = &trans->transaction->io_bgs; |
|
struct list_head *next; |
|
struct extent_buffer *eb; |
|
int ret; |
|
|
|
eb = btrfs_lock_root_node(fs_info->tree_root); |
|
ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, |
|
0, &eb, BTRFS_NESTING_COW); |
|
btrfs_tree_unlock(eb); |
|
free_extent_buffer(eb); |
|
|
|
if (ret) |
|
return ret; |
|
|
|
ret = btrfs_run_dev_stats(trans); |
|
if (ret) |
|
return ret; |
|
ret = btrfs_run_dev_replace(trans); |
|
if (ret) |
|
return ret; |
|
ret = btrfs_run_qgroups(trans); |
|
if (ret) |
|
return ret; |
|
|
|
ret = btrfs_setup_space_cache(trans); |
|
if (ret) |
|
return ret; |
|
|
|
again: |
|
while (!list_empty(&fs_info->dirty_cowonly_roots)) { |
|
struct btrfs_root *root; |
|
next = fs_info->dirty_cowonly_roots.next; |
|
list_del_init(next); |
|
root = list_entry(next, struct btrfs_root, dirty_list); |
|
clear_bit(BTRFS_ROOT_DIRTY, &root->state); |
|
|
|
if (root != fs_info->extent_root) |
|
list_add_tail(&root->dirty_list, |
|
&trans->transaction->switch_commits); |
|
ret = update_cowonly_root(trans, root); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
/* Now flush any delayed refs generated by updating all of the roots */ |
|
ret = btrfs_run_delayed_refs(trans, (unsigned long)-1); |
|
if (ret) |
|
return ret; |
|
|
|
while (!list_empty(dirty_bgs) || !list_empty(io_bgs)) { |
|
ret = btrfs_write_dirty_block_groups(trans); |
|
if (ret) |
|
return ret; |
|
|
|
/* |
|
* We're writing the dirty block groups, which could generate |
|
* delayed refs, which could generate more dirty block groups, |
|
* so we want to keep this flushing in this loop to make sure |
|
* everything gets run. |
|
*/ |
|
ret = btrfs_run_delayed_refs(trans, (unsigned long)-1); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
if (!list_empty(&fs_info->dirty_cowonly_roots)) |
|
goto again; |
|
|
|
list_add_tail(&fs_info->extent_root->dirty_list, |
|
&trans->transaction->switch_commits); |
|
|
|
/* Update dev-replace pointer once everything is committed */ |
|
fs_info->dev_replace.committed_cursor_left = |
|
fs_info->dev_replace.cursor_left_last_write_of_item; |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* dead roots are old snapshots that need to be deleted. This allocates |
|
* a dirty root struct and adds it into the list of dead roots that need to |
|
* be deleted |
|
*/ |
|
void btrfs_add_dead_root(struct btrfs_root *root) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
if (list_empty(&root->root_list)) { |
|
btrfs_grab_root(root); |
|
list_add_tail(&root->root_list, &fs_info->dead_roots); |
|
} |
|
spin_unlock(&fs_info->trans_lock); |
|
} |
|
|
|
/* |
|
* update all the cowonly tree roots on disk |
|
*/ |
|
static noinline int commit_fs_roots(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_root *gang[8]; |
|
int i; |
|
int ret; |
|
|
|
spin_lock(&fs_info->fs_roots_radix_lock); |
|
while (1) { |
|
ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix, |
|
(void **)gang, 0, |
|
ARRAY_SIZE(gang), |
|
BTRFS_ROOT_TRANS_TAG); |
|
if (ret == 0) |
|
break; |
|
for (i = 0; i < ret; i++) { |
|
struct btrfs_root *root = gang[i]; |
|
int ret2; |
|
|
|
radix_tree_tag_clear(&fs_info->fs_roots_radix, |
|
(unsigned long)root->root_key.objectid, |
|
BTRFS_ROOT_TRANS_TAG); |
|
spin_unlock(&fs_info->fs_roots_radix_lock); |
|
|
|
btrfs_free_log(trans, root); |
|
ret2 = btrfs_update_reloc_root(trans, root); |
|
if (ret2) |
|
return ret2; |
|
|
|
/* see comments in should_cow_block() */ |
|
clear_bit(BTRFS_ROOT_FORCE_COW, &root->state); |
|
smp_mb__after_atomic(); |
|
|
|
if (root->commit_root != root->node) { |
|
list_add_tail(&root->dirty_list, |
|
&trans->transaction->switch_commits); |
|
btrfs_set_root_node(&root->root_item, |
|
root->node); |
|
} |
|
|
|
ret2 = btrfs_update_root(trans, fs_info->tree_root, |
|
&root->root_key, |
|
&root->root_item); |
|
if (ret2) |
|
return ret2; |
|
spin_lock(&fs_info->fs_roots_radix_lock); |
|
btrfs_qgroup_free_meta_all_pertrans(root); |
|
} |
|
} |
|
spin_unlock(&fs_info->fs_roots_radix_lock); |
|
return 0; |
|
} |
|
|
|
/* |
|
* defrag a given btree. |
|
* Every leaf in the btree is read and defragged. |
|
*/ |
|
int btrfs_defrag_root(struct btrfs_root *root) |
|
{ |
|
struct btrfs_fs_info *info = root->fs_info; |
|
struct btrfs_trans_handle *trans; |
|
int ret; |
|
|
|
if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state)) |
|
return 0; |
|
|
|
while (1) { |
|
trans = btrfs_start_transaction(root, 0); |
|
if (IS_ERR(trans)) { |
|
ret = PTR_ERR(trans); |
|
break; |
|
} |
|
|
|
ret = btrfs_defrag_leaves(trans, root); |
|
|
|
btrfs_end_transaction(trans); |
|
btrfs_btree_balance_dirty(info); |
|
cond_resched(); |
|
|
|
if (btrfs_fs_closing(info) || ret != -EAGAIN) |
|
break; |
|
|
|
if (btrfs_defrag_cancelled(info)) { |
|
btrfs_debug(info, "defrag_root cancelled"); |
|
ret = -EAGAIN; |
|
break; |
|
} |
|
} |
|
clear_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Do all special snapshot related qgroup dirty hack. |
|
* |
|
* Will do all needed qgroup inherit and dirty hack like switch commit |
|
* roots inside one transaction and write all btree into disk, to make |
|
* qgroup works. |
|
*/ |
|
static int qgroup_account_snapshot(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *src, |
|
struct btrfs_root *parent, |
|
struct btrfs_qgroup_inherit *inherit, |
|
u64 dst_objectid) |
|
{ |
|
struct btrfs_fs_info *fs_info = src->fs_info; |
|
int ret; |
|
|
|
/* |
|
* Save some performance in the case that qgroups are not |
|
* enabled. If this check races with the ioctl, rescan will |
|
* kick in anyway. |
|
*/ |
|
if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) |
|
return 0; |
|
|
|
/* |
|
* Ensure dirty @src will be committed. Or, after coming |
|
* commit_fs_roots() and switch_commit_roots(), any dirty but not |
|
* recorded root will never be updated again, causing an outdated root |
|
* item. |
|
*/ |
|
ret = record_root_in_trans(trans, src, 1); |
|
if (ret) |
|
return ret; |
|
|
|
/* |
|
* btrfs_qgroup_inherit relies on a consistent view of the usage for the |
|
* src root, so we must run the delayed refs here. |
|
* |
|
* However this isn't particularly fool proof, because there's no |
|
* synchronization keeping us from changing the tree after this point |
|
* before we do the qgroup_inherit, or even from making changes while |
|
* we're doing the qgroup_inherit. But that's a problem for the future, |
|
* for now flush the delayed refs to narrow the race window where the |
|
* qgroup counters could end up wrong. |
|
*/ |
|
ret = btrfs_run_delayed_refs(trans, (unsigned long)-1); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
return ret; |
|
} |
|
|
|
/* |
|
* We are going to commit transaction, see btrfs_commit_transaction() |
|
* comment for reason locking tree_log_mutex |
|
*/ |
|
mutex_lock(&fs_info->tree_log_mutex); |
|
|
|
ret = commit_fs_roots(trans); |
|
if (ret) |
|
goto out; |
|
ret = btrfs_qgroup_account_extents(trans); |
|
if (ret < 0) |
|
goto out; |
|
|
|
/* Now qgroup are all updated, we can inherit it to new qgroups */ |
|
ret = btrfs_qgroup_inherit(trans, src->root_key.objectid, dst_objectid, |
|
inherit); |
|
if (ret < 0) |
|
goto out; |
|
|
|
/* |
|
* Now we do a simplified commit transaction, which will: |
|
* 1) commit all subvolume and extent tree |
|
* To ensure all subvolume and extent tree have a valid |
|
* commit_root to accounting later insert_dir_item() |
|
* 2) write all btree blocks onto disk |
|
* This is to make sure later btree modification will be cowed |
|
* Or commit_root can be populated and cause wrong qgroup numbers |
|
* In this simplified commit, we don't really care about other trees |
|
* like chunk and root tree, as they won't affect qgroup. |
|
* And we don't write super to avoid half committed status. |
|
*/ |
|
ret = commit_cowonly_roots(trans); |
|
if (ret) |
|
goto out; |
|
switch_commit_roots(trans); |
|
ret = btrfs_write_and_wait_transaction(trans); |
|
if (ret) |
|
btrfs_handle_fs_error(fs_info, ret, |
|
"Error while writing out transaction for qgroup"); |
|
|
|
out: |
|
mutex_unlock(&fs_info->tree_log_mutex); |
|
|
|
/* |
|
* Force parent root to be updated, as we recorded it before so its |
|
* last_trans == cur_transid. |
|
* Or it won't be committed again onto disk after later |
|
* insert_dir_item() |
|
*/ |
|
if (!ret) |
|
ret = record_root_in_trans(trans, parent, 1); |
|
return ret; |
|
} |
|
|
|
/* |
|
* new snapshots need to be created at a very specific time in the |
|
* transaction commit. This does the actual creation. |
|
* |
|
* Note: |
|
* If the error which may affect the commitment of the current transaction |
|
* happens, we should return the error number. If the error which just affect |
|
* the creation of the pending snapshots, just return 0. |
|
*/ |
|
static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, |
|
struct btrfs_pending_snapshot *pending) |
|
{ |
|
|
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_key key; |
|
struct btrfs_root_item *new_root_item; |
|
struct btrfs_root *tree_root = fs_info->tree_root; |
|
struct btrfs_root *root = pending->root; |
|
struct btrfs_root *parent_root; |
|
struct btrfs_block_rsv *rsv; |
|
struct inode *parent_inode; |
|
struct btrfs_path *path; |
|
struct btrfs_dir_item *dir_item; |
|
struct dentry *dentry; |
|
struct extent_buffer *tmp; |
|
struct extent_buffer *old; |
|
struct timespec64 cur_time; |
|
int ret = 0; |
|
u64 to_reserve = 0; |
|
u64 index = 0; |
|
u64 objectid; |
|
u64 root_flags; |
|
|
|
ASSERT(pending->path); |
|
path = pending->path; |
|
|
|
ASSERT(pending->root_item); |
|
new_root_item = pending->root_item; |
|
|
|
pending->error = btrfs_get_free_objectid(tree_root, &objectid); |
|
if (pending->error) |
|
goto no_free_objectid; |
|
|
|
/* |
|
* Make qgroup to skip current new snapshot's qgroupid, as it is |
|
* accounted by later btrfs_qgroup_inherit(). |
|
*/ |
|
btrfs_set_skip_qgroup(trans, objectid); |
|
|
|
btrfs_reloc_pre_snapshot(pending, &to_reserve); |
|
|
|
if (to_reserve > 0) { |
|
pending->error = btrfs_block_rsv_add(root, |
|
&pending->block_rsv, |
|
to_reserve, |
|
BTRFS_RESERVE_NO_FLUSH); |
|
if (pending->error) |
|
goto clear_skip_qgroup; |
|
} |
|
|
|
key.objectid = objectid; |
|
key.offset = (u64)-1; |
|
key.type = BTRFS_ROOT_ITEM_KEY; |
|
|
|
rsv = trans->block_rsv; |
|
trans->block_rsv = &pending->block_rsv; |
|
trans->bytes_reserved = trans->block_rsv->reserved; |
|
trace_btrfs_space_reservation(fs_info, "transaction", |
|
trans->transid, |
|
trans->bytes_reserved, 1); |
|
dentry = pending->dentry; |
|
parent_inode = pending->dir; |
|
parent_root = BTRFS_I(parent_inode)->root; |
|
ret = record_root_in_trans(trans, parent_root, 0); |
|
if (ret) |
|
goto fail; |
|
cur_time = current_time(parent_inode); |
|
|
|
/* |
|
* insert the directory item |
|
*/ |
|
ret = btrfs_set_inode_index(BTRFS_I(parent_inode), &index); |
|
BUG_ON(ret); /* -ENOMEM */ |
|
|
|
/* check if there is a file/dir which has the same name. */ |
|
dir_item = btrfs_lookup_dir_item(NULL, parent_root, path, |
|
btrfs_ino(BTRFS_I(parent_inode)), |
|
dentry->d_name.name, |
|
dentry->d_name.len, 0); |
|
if (dir_item != NULL && !IS_ERR(dir_item)) { |
|
pending->error = -EEXIST; |
|
goto dir_item_existed; |
|
} else if (IS_ERR(dir_item)) { |
|
ret = PTR_ERR(dir_item); |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
btrfs_release_path(path); |
|
|
|
/* |
|
* pull in the delayed directory update |
|
* and the delayed inode item |
|
* otherwise we corrupt the FS during |
|
* snapshot |
|
*/ |
|
ret = btrfs_run_delayed_items(trans); |
|
if (ret) { /* Transaction aborted */ |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
|
|
ret = record_root_in_trans(trans, root, 0); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
btrfs_set_root_last_snapshot(&root->root_item, trans->transid); |
|
memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); |
|
btrfs_check_and_init_root_item(new_root_item); |
|
|
|
root_flags = btrfs_root_flags(new_root_item); |
|
if (pending->readonly) |
|
root_flags |= BTRFS_ROOT_SUBVOL_RDONLY; |
|
else |
|
root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY; |
|
btrfs_set_root_flags(new_root_item, root_flags); |
|
|
|
btrfs_set_root_generation_v2(new_root_item, |
|
trans->transid); |
|
generate_random_guid(new_root_item->uuid); |
|
memcpy(new_root_item->parent_uuid, root->root_item.uuid, |
|
BTRFS_UUID_SIZE); |
|
if (!(root_flags & BTRFS_ROOT_SUBVOL_RDONLY)) { |
|
memset(new_root_item->received_uuid, 0, |
|
sizeof(new_root_item->received_uuid)); |
|
memset(&new_root_item->stime, 0, sizeof(new_root_item->stime)); |
|
memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime)); |
|
btrfs_set_root_stransid(new_root_item, 0); |
|
btrfs_set_root_rtransid(new_root_item, 0); |
|
} |
|
btrfs_set_stack_timespec_sec(&new_root_item->otime, cur_time.tv_sec); |
|
btrfs_set_stack_timespec_nsec(&new_root_item->otime, cur_time.tv_nsec); |
|
btrfs_set_root_otransid(new_root_item, trans->transid); |
|
|
|
old = btrfs_lock_root_node(root); |
|
ret = btrfs_cow_block(trans, root, old, NULL, 0, &old, |
|
BTRFS_NESTING_COW); |
|
if (ret) { |
|
btrfs_tree_unlock(old); |
|
free_extent_buffer(old); |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
|
|
ret = btrfs_copy_root(trans, root, old, &tmp, objectid); |
|
/* clean up in any case */ |
|
btrfs_tree_unlock(old); |
|
free_extent_buffer(old); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
/* see comments in should_cow_block() */ |
|
set_bit(BTRFS_ROOT_FORCE_COW, &root->state); |
|
smp_wmb(); |
|
|
|
btrfs_set_root_node(new_root_item, tmp); |
|
/* record when the snapshot was created in key.offset */ |
|
key.offset = trans->transid; |
|
ret = btrfs_insert_root(trans, tree_root, &key, new_root_item); |
|
btrfs_tree_unlock(tmp); |
|
free_extent_buffer(tmp); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
|
|
/* |
|
* insert root back/forward references |
|
*/ |
|
ret = btrfs_add_root_ref(trans, objectid, |
|
parent_root->root_key.objectid, |
|
btrfs_ino(BTRFS_I(parent_inode)), index, |
|
dentry->d_name.name, dentry->d_name.len); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
|
|
key.offset = (u64)-1; |
|
pending->snap = btrfs_get_new_fs_root(fs_info, objectid, pending->anon_dev); |
|
if (IS_ERR(pending->snap)) { |
|
ret = PTR_ERR(pending->snap); |
|
pending->snap = NULL; |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
|
|
ret = btrfs_reloc_post_snapshot(trans, pending); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
|
|
/* |
|
* Do special qgroup accounting for snapshot, as we do some qgroup |
|
* snapshot hack to do fast snapshot. |
|
* To co-operate with that hack, we do hack again. |
|
* Or snapshot will be greatly slowed down by a subtree qgroup rescan |
|
*/ |
|
ret = qgroup_account_snapshot(trans, root, parent_root, |
|
pending->inherit, objectid); |
|
if (ret < 0) |
|
goto fail; |
|
|
|
ret = btrfs_insert_dir_item(trans, dentry->d_name.name, |
|
dentry->d_name.len, BTRFS_I(parent_inode), |
|
&key, BTRFS_FT_DIR, index); |
|
/* We have check then name at the beginning, so it is impossible. */ |
|
BUG_ON(ret == -EEXIST || ret == -EOVERFLOW); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
|
|
btrfs_i_size_write(BTRFS_I(parent_inode), parent_inode->i_size + |
|
dentry->d_name.len * 2); |
|
parent_inode->i_mtime = parent_inode->i_ctime = |
|
current_time(parent_inode); |
|
ret = btrfs_update_inode_fallback(trans, parent_root, BTRFS_I(parent_inode)); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
ret = btrfs_uuid_tree_add(trans, new_root_item->uuid, |
|
BTRFS_UUID_KEY_SUBVOL, |
|
objectid); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
if (!btrfs_is_empty_uuid(new_root_item->received_uuid)) { |
|
ret = btrfs_uuid_tree_add(trans, new_root_item->received_uuid, |
|
BTRFS_UUID_KEY_RECEIVED_SUBVOL, |
|
objectid); |
|
if (ret && ret != -EEXIST) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto fail; |
|
} |
|
} |
|
|
|
fail: |
|
pending->error = ret; |
|
dir_item_existed: |
|
trans->block_rsv = rsv; |
|
trans->bytes_reserved = 0; |
|
clear_skip_qgroup: |
|
btrfs_clear_skip_qgroup(trans); |
|
no_free_objectid: |
|
kfree(new_root_item); |
|
pending->root_item = NULL; |
|
btrfs_free_path(path); |
|
pending->path = NULL; |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* create all the snapshots we've scheduled for creation |
|
*/ |
|
static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_pending_snapshot *pending, *next; |
|
struct list_head *head = &trans->transaction->pending_snapshots; |
|
int ret = 0; |
|
|
|
list_for_each_entry_safe(pending, next, head, list) { |
|
list_del(&pending->list); |
|
ret = create_pending_snapshot(trans, pending); |
|
if (ret) |
|
break; |
|
} |
|
return ret; |
|
} |
|
|
|
static void update_super_roots(struct btrfs_fs_info *fs_info) |
|
{ |
|
struct btrfs_root_item *root_item; |
|
struct btrfs_super_block *super; |
|
|
|
super = fs_info->super_copy; |
|
|
|
root_item = &fs_info->chunk_root->root_item; |
|
super->chunk_root = root_item->bytenr; |
|
super->chunk_root_generation = root_item->generation; |
|
super->chunk_root_level = root_item->level; |
|
|
|
root_item = &fs_info->tree_root->root_item; |
|
super->root = root_item->bytenr; |
|
super->generation = root_item->generation; |
|
super->root_level = root_item->level; |
|
if (btrfs_test_opt(fs_info, SPACE_CACHE)) |
|
super->cache_generation = root_item->generation; |
|
else if (test_bit(BTRFS_FS_CLEANUP_SPACE_CACHE_V1, &fs_info->flags)) |
|
super->cache_generation = 0; |
|
if (test_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags)) |
|
super->uuid_tree_generation = root_item->generation; |
|
} |
|
|
|
int btrfs_transaction_in_commit(struct btrfs_fs_info *info) |
|
{ |
|
struct btrfs_transaction *trans; |
|
int ret = 0; |
|
|
|
spin_lock(&info->trans_lock); |
|
trans = info->running_transaction; |
|
if (trans) |
|
ret = (trans->state >= TRANS_STATE_COMMIT_START); |
|
spin_unlock(&info->trans_lock); |
|
return ret; |
|
} |
|
|
|
int btrfs_transaction_blocked(struct btrfs_fs_info *info) |
|
{ |
|
struct btrfs_transaction *trans; |
|
int ret = 0; |
|
|
|
spin_lock(&info->trans_lock); |
|
trans = info->running_transaction; |
|
if (trans) |
|
ret = is_transaction_blocked(trans); |
|
spin_unlock(&info->trans_lock); |
|
return ret; |
|
} |
|
|
|
/* |
|
* commit transactions asynchronously. once btrfs_commit_transaction_async |
|
* returns, any subsequent transaction will not be allowed to join. |
|
*/ |
|
struct btrfs_async_commit { |
|
struct btrfs_trans_handle *newtrans; |
|
struct work_struct work; |
|
}; |
|
|
|
static void do_async_commit(struct work_struct *work) |
|
{ |
|
struct btrfs_async_commit *ac = |
|
container_of(work, struct btrfs_async_commit, work); |
|
|
|
/* |
|
* We've got freeze protection passed with the transaction. |
|
* Tell lockdep about it. |
|
*/ |
|
if (ac->newtrans->type & __TRANS_FREEZABLE) |
|
__sb_writers_acquired(ac->newtrans->fs_info->sb, SB_FREEZE_FS); |
|
|
|
current->journal_info = ac->newtrans; |
|
|
|
btrfs_commit_transaction(ac->newtrans); |
|
kfree(ac); |
|
} |
|
|
|
int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_async_commit *ac; |
|
struct btrfs_transaction *cur_trans; |
|
|
|
ac = kmalloc(sizeof(*ac), GFP_NOFS); |
|
if (!ac) |
|
return -ENOMEM; |
|
|
|
INIT_WORK(&ac->work, do_async_commit); |
|
ac->newtrans = btrfs_join_transaction(trans->root); |
|
if (IS_ERR(ac->newtrans)) { |
|
int err = PTR_ERR(ac->newtrans); |
|
kfree(ac); |
|
return err; |
|
} |
|
|
|
/* take transaction reference */ |
|
cur_trans = trans->transaction; |
|
refcount_inc(&cur_trans->use_count); |
|
|
|
btrfs_end_transaction(trans); |
|
|
|
/* |
|
* Tell lockdep we've released the freeze rwsem, since the |
|
* async commit thread will be the one to unlock it. |
|
*/ |
|
if (ac->newtrans->type & __TRANS_FREEZABLE) |
|
__sb_writers_release(fs_info->sb, SB_FREEZE_FS); |
|
|
|
schedule_work(&ac->work); |
|
/* |
|
* Wait for the current transaction commit to start and block |
|
* subsequent transaction joins |
|
*/ |
|
wait_event(fs_info->transaction_blocked_wait, |
|
cur_trans->state >= TRANS_STATE_COMMIT_START || |
|
TRANS_ABORTED(cur_trans)); |
|
if (current->journal_info == trans) |
|
current->journal_info = NULL; |
|
|
|
btrfs_put_transaction(cur_trans); |
|
return 0; |
|
} |
|
|
|
|
|
static void cleanup_transaction(struct btrfs_trans_handle *trans, int err) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_transaction *cur_trans = trans->transaction; |
|
|
|
WARN_ON(refcount_read(&trans->use_count) > 1); |
|
|
|
btrfs_abort_transaction(trans, err); |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
|
|
/* |
|
* If the transaction is removed from the list, it means this |
|
* transaction has been committed successfully, so it is impossible |
|
* to call the cleanup function. |
|
*/ |
|
BUG_ON(list_empty(&cur_trans->list)); |
|
|
|
if (cur_trans == fs_info->running_transaction) { |
|
cur_trans->state = TRANS_STATE_COMMIT_DOING; |
|
spin_unlock(&fs_info->trans_lock); |
|
wait_event(cur_trans->writer_wait, |
|
atomic_read(&cur_trans->num_writers) == 1); |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
} |
|
|
|
/* |
|
* Now that we know no one else is still using the transaction we can |
|
* remove the transaction from the list of transactions. This avoids |
|
* the transaction kthread from cleaning up the transaction while some |
|
* other task is still using it, which could result in a use-after-free |
|
* on things like log trees, as it forces the transaction kthread to |
|
* wait for this transaction to be cleaned up by us. |
|
*/ |
|
list_del_init(&cur_trans->list); |
|
|
|
spin_unlock(&fs_info->trans_lock); |
|
|
|
btrfs_cleanup_one_transaction(trans->transaction, fs_info); |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
if (cur_trans == fs_info->running_transaction) |
|
fs_info->running_transaction = NULL; |
|
spin_unlock(&fs_info->trans_lock); |
|
|
|
if (trans->type & __TRANS_FREEZABLE) |
|
sb_end_intwrite(fs_info->sb); |
|
btrfs_put_transaction(cur_trans); |
|
btrfs_put_transaction(cur_trans); |
|
|
|
trace_btrfs_transaction_commit(trans->root); |
|
|
|
if (current->journal_info == trans) |
|
current->journal_info = NULL; |
|
btrfs_scrub_cancel(fs_info); |
|
|
|
kmem_cache_free(btrfs_trans_handle_cachep, trans); |
|
} |
|
|
|
/* |
|
* Release reserved delayed ref space of all pending block groups of the |
|
* transaction and remove them from the list |
|
*/ |
|
static void btrfs_cleanup_pending_block_groups(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_block_group *block_group, *tmp; |
|
|
|
list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) { |
|
btrfs_delayed_refs_rsv_release(fs_info, 1); |
|
list_del_init(&block_group->bg_list); |
|
} |
|
} |
|
|
|
static inline int btrfs_start_delalloc_flush(struct btrfs_fs_info *fs_info) |
|
{ |
|
/* |
|
* We use writeback_inodes_sb here because if we used |
|
* btrfs_start_delalloc_roots we would deadlock with fs freeze. |
|
* Currently are holding the fs freeze lock, if we do an async flush |
|
* we'll do btrfs_join_transaction() and deadlock because we need to |
|
* wait for the fs freeze lock. Using the direct flushing we benefit |
|
* from already being in a transaction and our join_transaction doesn't |
|
* have to re-take the fs freeze lock. |
|
*/ |
|
if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) |
|
writeback_inodes_sb(fs_info->sb, WB_REASON_SYNC); |
|
return 0; |
|
} |
|
|
|
static inline void btrfs_wait_delalloc_flush(struct btrfs_fs_info *fs_info) |
|
{ |
|
if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) |
|
btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); |
|
} |
|
|
|
int btrfs_commit_transaction(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_transaction *cur_trans = trans->transaction; |
|
struct btrfs_transaction *prev_trans = NULL; |
|
int ret; |
|
|
|
ASSERT(refcount_read(&trans->use_count) == 1); |
|
|
|
/* Stop the commit early if ->aborted is set */ |
|
if (TRANS_ABORTED(cur_trans)) { |
|
ret = cur_trans->aborted; |
|
btrfs_end_transaction(trans); |
|
return ret; |
|
} |
|
|
|
btrfs_trans_release_metadata(trans); |
|
trans->block_rsv = NULL; |
|
|
|
/* |
|
* We only want one transaction commit doing the flushing so we do not |
|
* waste a bunch of time on lock contention on the extent root node. |
|
*/ |
|
if (!test_and_set_bit(BTRFS_DELAYED_REFS_FLUSHING, |
|
&cur_trans->delayed_refs.flags)) { |
|
/* |
|
* Make a pass through all the delayed refs we have so far. |
|
* Any running threads may add more while we are here. |
|
*/ |
|
ret = btrfs_run_delayed_refs(trans, 0); |
|
if (ret) { |
|
btrfs_end_transaction(trans); |
|
return ret; |
|
} |
|
} |
|
|
|
btrfs_create_pending_block_groups(trans); |
|
|
|
if (!test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &cur_trans->flags)) { |
|
int run_it = 0; |
|
|
|
/* this mutex is also taken before trying to set |
|
* block groups readonly. We need to make sure |
|
* that nobody has set a block group readonly |
|
* after a extents from that block group have been |
|
* allocated for cache files. btrfs_set_block_group_ro |
|
* will wait for the transaction to commit if it |
|
* finds BTRFS_TRANS_DIRTY_BG_RUN set. |
|
* |
|
* The BTRFS_TRANS_DIRTY_BG_RUN flag is also used to make sure |
|
* only one process starts all the block group IO. It wouldn't |
|
* hurt to have more than one go through, but there's no |
|
* real advantage to it either. |
|
*/ |
|
mutex_lock(&fs_info->ro_block_group_mutex); |
|
if (!test_and_set_bit(BTRFS_TRANS_DIRTY_BG_RUN, |
|
&cur_trans->flags)) |
|
run_it = 1; |
|
mutex_unlock(&fs_info->ro_block_group_mutex); |
|
|
|
if (run_it) { |
|
ret = btrfs_start_dirty_block_groups(trans); |
|
if (ret) { |
|
btrfs_end_transaction(trans); |
|
return ret; |
|
} |
|
} |
|
} |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
if (cur_trans->state >= TRANS_STATE_COMMIT_START) { |
|
enum btrfs_trans_state want_state = TRANS_STATE_COMPLETED; |
|
|
|
spin_unlock(&fs_info->trans_lock); |
|
refcount_inc(&cur_trans->use_count); |
|
|
|
if (trans->in_fsync) |
|
want_state = TRANS_STATE_SUPER_COMMITTED; |
|
ret = btrfs_end_transaction(trans); |
|
wait_for_commit(cur_trans, want_state); |
|
|
|
if (TRANS_ABORTED(cur_trans)) |
|
ret = cur_trans->aborted; |
|
|
|
btrfs_put_transaction(cur_trans); |
|
|
|
return ret; |
|
} |
|
|
|
cur_trans->state = TRANS_STATE_COMMIT_START; |
|
wake_up(&fs_info->transaction_blocked_wait); |
|
|
|
if (cur_trans->list.prev != &fs_info->trans_list) { |
|
enum btrfs_trans_state want_state = TRANS_STATE_COMPLETED; |
|
|
|
if (trans->in_fsync) |
|
want_state = TRANS_STATE_SUPER_COMMITTED; |
|
|
|
prev_trans = list_entry(cur_trans->list.prev, |
|
struct btrfs_transaction, list); |
|
if (prev_trans->state < want_state) { |
|
refcount_inc(&prev_trans->use_count); |
|
spin_unlock(&fs_info->trans_lock); |
|
|
|
wait_for_commit(prev_trans, want_state); |
|
|
|
ret = READ_ONCE(prev_trans->aborted); |
|
|
|
btrfs_put_transaction(prev_trans); |
|
if (ret) |
|
goto cleanup_transaction; |
|
} else { |
|
spin_unlock(&fs_info->trans_lock); |
|
} |
|
} else { |
|
spin_unlock(&fs_info->trans_lock); |
|
/* |
|
* The previous transaction was aborted and was already removed |
|
* from the list of transactions at fs_info->trans_list. So we |
|
* abort to prevent writing a new superblock that reflects a |
|
* corrupt state (pointing to trees with unwritten nodes/leafs). |
|
*/ |
|
if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state)) { |
|
ret = -EROFS; |
|
goto cleanup_transaction; |
|
} |
|
} |
|
|
|
extwriter_counter_dec(cur_trans, trans->type); |
|
|
|
ret = btrfs_start_delalloc_flush(fs_info); |
|
if (ret) |
|
goto cleanup_transaction; |
|
|
|
ret = btrfs_run_delayed_items(trans); |
|
if (ret) |
|
goto cleanup_transaction; |
|
|
|
wait_event(cur_trans->writer_wait, |
|
extwriter_counter_read(cur_trans) == 0); |
|
|
|
/* some pending stuffs might be added after the previous flush. */ |
|
ret = btrfs_run_delayed_items(trans); |
|
if (ret) |
|
goto cleanup_transaction; |
|
|
|
btrfs_wait_delalloc_flush(fs_info); |
|
|
|
/* |
|
* Wait for all ordered extents started by a fast fsync that joined this |
|
* transaction. Otherwise if this transaction commits before the ordered |
|
* extents complete we lose logged data after a power failure. |
|
*/ |
|
wait_event(cur_trans->pending_wait, |
|
atomic_read(&cur_trans->pending_ordered) == 0); |
|
|
|
btrfs_scrub_pause(fs_info); |
|
/* |
|
* Ok now we need to make sure to block out any other joins while we |
|
* commit the transaction. We could have started a join before setting |
|
* COMMIT_DOING so make sure to wait for num_writers to == 1 again. |
|
*/ |
|
spin_lock(&fs_info->trans_lock); |
|
cur_trans->state = TRANS_STATE_COMMIT_DOING; |
|
spin_unlock(&fs_info->trans_lock); |
|
wait_event(cur_trans->writer_wait, |
|
atomic_read(&cur_trans->num_writers) == 1); |
|
|
|
if (TRANS_ABORTED(cur_trans)) { |
|
ret = cur_trans->aborted; |
|
goto scrub_continue; |
|
} |
|
/* |
|
* the reloc mutex makes sure that we stop |
|
* the balancing code from coming in and moving |
|
* extents around in the middle of the commit |
|
*/ |
|
mutex_lock(&fs_info->reloc_mutex); |
|
|
|
/* |
|
* We needn't worry about the delayed items because we will |
|
* deal with them in create_pending_snapshot(), which is the |
|
* core function of the snapshot creation. |
|
*/ |
|
ret = create_pending_snapshots(trans); |
|
if (ret) |
|
goto unlock_reloc; |
|
|
|
/* |
|
* We insert the dir indexes of the snapshots and update the inode |
|
* of the snapshots' parents after the snapshot creation, so there |
|
* are some delayed items which are not dealt with. Now deal with |
|
* them. |
|
* |
|
* We needn't worry that this operation will corrupt the snapshots, |
|
* because all the tree which are snapshoted will be forced to COW |
|
* the nodes and leaves. |
|
*/ |
|
ret = btrfs_run_delayed_items(trans); |
|
if (ret) |
|
goto unlock_reloc; |
|
|
|
ret = btrfs_run_delayed_refs(trans, (unsigned long)-1); |
|
if (ret) |
|
goto unlock_reloc; |
|
|
|
/* |
|
* make sure none of the code above managed to slip in a |
|
* delayed item |
|
*/ |
|
btrfs_assert_delayed_root_empty(fs_info); |
|
|
|
WARN_ON(cur_trans != trans->transaction); |
|
|
|
/* btrfs_commit_tree_roots is responsible for getting the |
|
* various roots consistent with each other. Every pointer |
|
* in the tree of tree roots has to point to the most up to date |
|
* root for every subvolume and other tree. So, we have to keep |
|
* the tree logging code from jumping in and changing any |
|
* of the trees. |
|
* |
|
* At this point in the commit, there can't be any tree-log |
|
* writers, but a little lower down we drop the trans mutex |
|
* and let new people in. By holding the tree_log_mutex |
|
* from now until after the super is written, we avoid races |
|
* with the tree-log code. |
|
*/ |
|
mutex_lock(&fs_info->tree_log_mutex); |
|
|
|
ret = commit_fs_roots(trans); |
|
if (ret) |
|
goto unlock_tree_log; |
|
|
|
/* |
|
* Since the transaction is done, we can apply the pending changes |
|
* before the next transaction. |
|
*/ |
|
btrfs_apply_pending_changes(fs_info); |
|
|
|
/* commit_fs_roots gets rid of all the tree log roots, it is now |
|
* safe to free the root of tree log roots |
|
*/ |
|
btrfs_free_log_root_tree(trans, fs_info); |
|
|
|
/* |
|
* Since fs roots are all committed, we can get a quite accurate |
|
* new_roots. So let's do quota accounting. |
|
*/ |
|
ret = btrfs_qgroup_account_extents(trans); |
|
if (ret < 0) |
|
goto unlock_tree_log; |
|
|
|
ret = commit_cowonly_roots(trans); |
|
if (ret) |
|
goto unlock_tree_log; |
|
|
|
/* |
|
* The tasks which save the space cache and inode cache may also |
|
* update ->aborted, check it. |
|
*/ |
|
if (TRANS_ABORTED(cur_trans)) { |
|
ret = cur_trans->aborted; |
|
goto unlock_tree_log; |
|
} |
|
|
|
cur_trans = fs_info->running_transaction; |
|
|
|
btrfs_set_root_node(&fs_info->tree_root->root_item, |
|
fs_info->tree_root->node); |
|
list_add_tail(&fs_info->tree_root->dirty_list, |
|
&cur_trans->switch_commits); |
|
|
|
btrfs_set_root_node(&fs_info->chunk_root->root_item, |
|
fs_info->chunk_root->node); |
|
list_add_tail(&fs_info->chunk_root->dirty_list, |
|
&cur_trans->switch_commits); |
|
|
|
switch_commit_roots(trans); |
|
|
|
ASSERT(list_empty(&cur_trans->dirty_bgs)); |
|
ASSERT(list_empty(&cur_trans->io_bgs)); |
|
update_super_roots(fs_info); |
|
|
|
btrfs_set_super_log_root(fs_info->super_copy, 0); |
|
btrfs_set_super_log_root_level(fs_info->super_copy, 0); |
|
memcpy(fs_info->super_for_commit, fs_info->super_copy, |
|
sizeof(*fs_info->super_copy)); |
|
|
|
btrfs_commit_device_sizes(cur_trans); |
|
|
|
clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags); |
|
clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags); |
|
|
|
btrfs_trans_release_chunk_metadata(trans); |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
cur_trans->state = TRANS_STATE_UNBLOCKED; |
|
fs_info->running_transaction = NULL; |
|
spin_unlock(&fs_info->trans_lock); |
|
mutex_unlock(&fs_info->reloc_mutex); |
|
|
|
wake_up(&fs_info->transaction_wait); |
|
|
|
ret = btrfs_write_and_wait_transaction(trans); |
|
if (ret) { |
|
btrfs_handle_fs_error(fs_info, ret, |
|
"Error while writing out transaction"); |
|
/* |
|
* reloc_mutex has been unlocked, tree_log_mutex is still held |
|
* but we can't jump to unlock_tree_log causing double unlock |
|
*/ |
|
mutex_unlock(&fs_info->tree_log_mutex); |
|
goto scrub_continue; |
|
} |
|
|
|
/* |
|
* At this point, we should have written all the tree blocks allocated |
|
* in this transaction. So it's now safe to free the redirtyied extent |
|
* buffers. |
|
*/ |
|
btrfs_free_redirty_list(cur_trans); |
|
|
|
ret = write_all_supers(fs_info, 0); |
|
/* |
|
* the super is written, we can safely allow the tree-loggers |
|
* to go about their business |
|
*/ |
|
mutex_unlock(&fs_info->tree_log_mutex); |
|
if (ret) |
|
goto scrub_continue; |
|
|
|
/* |
|
* We needn't acquire the lock here because there is no other task |
|
* which can change it. |
|
*/ |
|
cur_trans->state = TRANS_STATE_SUPER_COMMITTED; |
|
wake_up(&cur_trans->commit_wait); |
|
|
|
btrfs_finish_extent_commit(trans); |
|
|
|
if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &cur_trans->flags)) |
|
btrfs_clear_space_info_full(fs_info); |
|
|
|
fs_info->last_trans_committed = cur_trans->transid; |
|
/* |
|
* We needn't acquire the lock here because there is no other task |
|
* which can change it. |
|
*/ |
|
cur_trans->state = TRANS_STATE_COMPLETED; |
|
wake_up(&cur_trans->commit_wait); |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
list_del_init(&cur_trans->list); |
|
spin_unlock(&fs_info->trans_lock); |
|
|
|
btrfs_put_transaction(cur_trans); |
|
btrfs_put_transaction(cur_trans); |
|
|
|
if (trans->type & __TRANS_FREEZABLE) |
|
sb_end_intwrite(fs_info->sb); |
|
|
|
trace_btrfs_transaction_commit(trans->root); |
|
|
|
btrfs_scrub_continue(fs_info); |
|
|
|
if (current->journal_info == trans) |
|
current->journal_info = NULL; |
|
|
|
kmem_cache_free(btrfs_trans_handle_cachep, trans); |
|
|
|
return ret; |
|
|
|
unlock_tree_log: |
|
mutex_unlock(&fs_info->tree_log_mutex); |
|
unlock_reloc: |
|
mutex_unlock(&fs_info->reloc_mutex); |
|
scrub_continue: |
|
btrfs_scrub_continue(fs_info); |
|
cleanup_transaction: |
|
btrfs_trans_release_metadata(trans); |
|
btrfs_cleanup_pending_block_groups(trans); |
|
btrfs_trans_release_chunk_metadata(trans); |
|
trans->block_rsv = NULL; |
|
btrfs_warn(fs_info, "Skipping commit of aborted transaction."); |
|
if (current->journal_info == trans) |
|
current->journal_info = NULL; |
|
cleanup_transaction(trans, ret); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* return < 0 if error |
|
* 0 if there are no more dead_roots at the time of call |
|
* 1 there are more to be processed, call me again |
|
* |
|
* The return value indicates there are certainly more snapshots to delete, but |
|
* if there comes a new one during processing, it may return 0. We don't mind, |
|
* because btrfs_commit_super will poke cleaner thread and it will process it a |
|
* few seconds later. |
|
*/ |
|
int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root) |
|
{ |
|
int ret; |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
|
|
spin_lock(&fs_info->trans_lock); |
|
if (list_empty(&fs_info->dead_roots)) { |
|
spin_unlock(&fs_info->trans_lock); |
|
return 0; |
|
} |
|
root = list_first_entry(&fs_info->dead_roots, |
|
struct btrfs_root, root_list); |
|
list_del_init(&root->root_list); |
|
spin_unlock(&fs_info->trans_lock); |
|
|
|
btrfs_debug(fs_info, "cleaner removing %llu", root->root_key.objectid); |
|
|
|
btrfs_kill_all_delayed_nodes(root); |
|
|
|
if (btrfs_header_backref_rev(root->node) < |
|
BTRFS_MIXED_BACKREF_REV) |
|
ret = btrfs_drop_snapshot(root, 0, 0); |
|
else |
|
ret = btrfs_drop_snapshot(root, 1, 0); |
|
|
|
btrfs_put_root(root); |
|
return (ret < 0) ? 0 : 1; |
|
} |
|
|
|
void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info) |
|
{ |
|
unsigned long prev; |
|
unsigned long bit; |
|
|
|
prev = xchg(&fs_info->pending_changes, 0); |
|
if (!prev) |
|
return; |
|
|
|
bit = 1 << BTRFS_PENDING_COMMIT; |
|
if (prev & bit) |
|
btrfs_debug(fs_info, "pending commit done"); |
|
prev &= ~bit; |
|
|
|
if (prev) |
|
btrfs_warn(fs_info, |
|
"unknown pending changes left 0x%lx, ignoring", prev); |
|
}
|
|
|