diff options
Diffstat (limited to 'fs/btrfs/transaction.c')
-rw-r--r-- | fs/btrfs/transaction.c | 37 |
1 files changed, 34 insertions, 3 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 67e84939b758..e18eb75e6fa3 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -454,7 +454,7 @@ start_transaction(struct btrfs_root *root, unsigned int num_items, 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; @@ -483,13 +483,28 @@ start_transaction(struct btrfs_root *root, unsigned int num_items, * 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_trans_metadata_size(fs_info, num_items); + if (delayed_refs_rsv->full == 0) { + delayed_refs_bytes = num_bytes; + num_bytes <<= 1; + } + /* * Do the reservation for the relocation root creation */ @@ -498,8 +513,24 @@ start_transaction(struct btrfs_root *root, unsigned int num_items, reloc_reserved = true; } - ret = btrfs_block_rsv_add(root, &fs_info->trans_block_rsv, - num_bytes, flush); + 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; + } + } 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; } |