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![Josef Bacik](/assets/img/avatar_default.png)
Now that these two structs are the same, move the btrfs_data_ref and btrfs_tree_ref up and use these in the btrfs_delayed_ref_node. Then remove the btrfs_delayed_*_ref structs. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
1198 lines
34 KiB
C
1198 lines
34 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2009 Oracle. All rights reserved.
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*/
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/sort.h>
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#include "messages.h"
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#include "ctree.h"
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#include "delayed-ref.h"
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#include "transaction.h"
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#include "qgroup.h"
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#include "space-info.h"
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#include "tree-mod-log.h"
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#include "fs.h"
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struct kmem_cache *btrfs_delayed_ref_head_cachep;
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struct kmem_cache *btrfs_delayed_ref_node_cachep;
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struct kmem_cache *btrfs_delayed_extent_op_cachep;
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/*
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* delayed back reference update tracking. For subvolume trees
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* we queue up extent allocations and backref maintenance for
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* delayed processing. This avoids deep call chains where we
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* add extents in the middle of btrfs_search_slot, and it allows
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* us to buffer up frequently modified backrefs in an rb tree instead
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* of hammering updates on the extent allocation tree.
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*/
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bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info)
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{
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struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
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struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
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bool ret = false;
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u64 reserved;
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spin_lock(&global_rsv->lock);
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reserved = global_rsv->reserved;
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spin_unlock(&global_rsv->lock);
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/*
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* Since the global reserve is just kind of magic we don't really want
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* to rely on it to save our bacon, so if our size is more than the
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* delayed_refs_rsv and the global rsv then it's time to think about
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* bailing.
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*/
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spin_lock(&delayed_refs_rsv->lock);
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reserved += delayed_refs_rsv->reserved;
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if (delayed_refs_rsv->size >= reserved)
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ret = true;
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spin_unlock(&delayed_refs_rsv->lock);
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return ret;
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}
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/*
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* Release a ref head's reservation.
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*
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* @fs_info: the filesystem
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* @nr_refs: number of delayed refs to drop
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* @nr_csums: number of csum items to drop
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*
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* Drops the delayed ref head's count from the delayed refs rsv and free any
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* excess reservation we had.
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*/
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void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr_refs, int nr_csums)
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{
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struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
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u64 num_bytes;
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u64 released;
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num_bytes = btrfs_calc_delayed_ref_bytes(fs_info, nr_refs);
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num_bytes += btrfs_calc_delayed_ref_csum_bytes(fs_info, nr_csums);
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released = btrfs_block_rsv_release(fs_info, block_rsv, num_bytes, NULL);
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if (released)
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trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
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0, released, 0);
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}
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/*
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* Adjust the size of the delayed refs rsv.
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*
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* This is to be called anytime we may have adjusted trans->delayed_ref_updates
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* or trans->delayed_ref_csum_deletions, it'll calculate the additional size and
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* add it to the delayed_refs_rsv.
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*/
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void btrfs_update_delayed_refs_rsv(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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struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
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struct btrfs_block_rsv *local_rsv = &trans->delayed_rsv;
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u64 num_bytes;
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u64 reserved_bytes;
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num_bytes = btrfs_calc_delayed_ref_bytes(fs_info, trans->delayed_ref_updates);
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num_bytes += btrfs_calc_delayed_ref_csum_bytes(fs_info,
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trans->delayed_ref_csum_deletions);
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if (num_bytes == 0)
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return;
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/*
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* Try to take num_bytes from the transaction's local delayed reserve.
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* If not possible, try to take as much as it's available. If the local
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* reserve doesn't have enough reserved space, the delayed refs reserve
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* will be refilled next time btrfs_delayed_refs_rsv_refill() is called
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* by someone or if a transaction commit is triggered before that, the
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* global block reserve will be used. We want to minimize using the
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* global block reserve for cases we can account for in advance, to
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* avoid exhausting it and reach -ENOSPC during a transaction commit.
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*/
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spin_lock(&local_rsv->lock);
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reserved_bytes = min(num_bytes, local_rsv->reserved);
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local_rsv->reserved -= reserved_bytes;
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local_rsv->full = (local_rsv->reserved >= local_rsv->size);
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spin_unlock(&local_rsv->lock);
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spin_lock(&delayed_rsv->lock);
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delayed_rsv->size += num_bytes;
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delayed_rsv->reserved += reserved_bytes;
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delayed_rsv->full = (delayed_rsv->reserved >= delayed_rsv->size);
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spin_unlock(&delayed_rsv->lock);
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trans->delayed_ref_updates = 0;
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trans->delayed_ref_csum_deletions = 0;
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}
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/*
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* Adjust the size of the delayed refs block reserve for 1 block group item
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* insertion, used after allocating a block group.
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*/
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void btrfs_inc_delayed_refs_rsv_bg_inserts(struct btrfs_fs_info *fs_info)
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{
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struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
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spin_lock(&delayed_rsv->lock);
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/*
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* Inserting a block group item does not require changing the free space
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* tree, only the extent tree or the block group tree, so this is all we
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* need.
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*/
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delayed_rsv->size += btrfs_calc_insert_metadata_size(fs_info, 1);
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delayed_rsv->full = false;
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spin_unlock(&delayed_rsv->lock);
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}
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/*
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* Adjust the size of the delayed refs block reserve to release space for 1
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* block group item insertion.
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*/
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void btrfs_dec_delayed_refs_rsv_bg_inserts(struct btrfs_fs_info *fs_info)
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{
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struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
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const u64 num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
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u64 released;
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released = btrfs_block_rsv_release(fs_info, delayed_rsv, num_bytes, NULL);
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if (released > 0)
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trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
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0, released, 0);
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}
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/*
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* Adjust the size of the delayed refs block reserve for 1 block group item
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* update.
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*/
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void btrfs_inc_delayed_refs_rsv_bg_updates(struct btrfs_fs_info *fs_info)
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{
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struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
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spin_lock(&delayed_rsv->lock);
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/*
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* Updating a block group item does not result in new nodes/leaves and
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* does not require changing the free space tree, only the extent tree
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* or the block group tree, so this is all we need.
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*/
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delayed_rsv->size += btrfs_calc_metadata_size(fs_info, 1);
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delayed_rsv->full = false;
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spin_unlock(&delayed_rsv->lock);
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}
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/*
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* Adjust the size of the delayed refs block reserve to release space for 1
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* block group item update.
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*/
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void btrfs_dec_delayed_refs_rsv_bg_updates(struct btrfs_fs_info *fs_info)
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{
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struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
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const u64 num_bytes = btrfs_calc_metadata_size(fs_info, 1);
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u64 released;
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released = btrfs_block_rsv_release(fs_info, delayed_rsv, num_bytes, NULL);
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if (released > 0)
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trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
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0, released, 0);
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}
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/*
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* Transfer bytes to our delayed refs rsv.
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*
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* @fs_info: the filesystem
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* @num_bytes: number of bytes to transfer
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*
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* This transfers up to the num_bytes amount, previously reserved, to the
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* delayed_refs_rsv. Any extra bytes are returned to the space info.
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*/
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void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
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u64 num_bytes)
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{
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struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
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u64 to_free = 0;
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spin_lock(&delayed_refs_rsv->lock);
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if (delayed_refs_rsv->size > delayed_refs_rsv->reserved) {
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u64 delta = delayed_refs_rsv->size -
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delayed_refs_rsv->reserved;
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if (num_bytes > delta) {
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to_free = num_bytes - delta;
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num_bytes = delta;
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}
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} else {
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to_free = num_bytes;
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num_bytes = 0;
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}
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if (num_bytes)
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delayed_refs_rsv->reserved += num_bytes;
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if (delayed_refs_rsv->reserved >= delayed_refs_rsv->size)
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delayed_refs_rsv->full = true;
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spin_unlock(&delayed_refs_rsv->lock);
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if (num_bytes)
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trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
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0, num_bytes, 1);
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if (to_free)
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btrfs_space_info_free_bytes_may_use(fs_info,
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delayed_refs_rsv->space_info, to_free);
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}
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/*
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* Refill based on our delayed refs usage.
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*
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* @fs_info: the filesystem
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* @flush: control how we can flush for this reservation.
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*
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* This will refill the delayed block_rsv up to 1 items size worth of space and
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* will return -ENOSPC if we can't make the reservation.
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*/
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int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
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enum btrfs_reserve_flush_enum flush)
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{
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struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
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struct btrfs_space_info *space_info = block_rsv->space_info;
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u64 limit = btrfs_calc_delayed_ref_bytes(fs_info, 1);
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u64 num_bytes = 0;
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u64 refilled_bytes;
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u64 to_free;
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int ret = -ENOSPC;
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spin_lock(&block_rsv->lock);
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if (block_rsv->reserved < block_rsv->size) {
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num_bytes = block_rsv->size - block_rsv->reserved;
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num_bytes = min(num_bytes, limit);
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}
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spin_unlock(&block_rsv->lock);
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if (!num_bytes)
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return 0;
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ret = btrfs_reserve_metadata_bytes(fs_info, space_info, num_bytes, flush);
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if (ret)
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return ret;
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/*
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* We may have raced with someone else, so check again if we the block
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* reserve is still not full and release any excess space.
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*/
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spin_lock(&block_rsv->lock);
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if (block_rsv->reserved < block_rsv->size) {
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u64 needed = block_rsv->size - block_rsv->reserved;
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if (num_bytes >= needed) {
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block_rsv->reserved += needed;
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block_rsv->full = true;
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to_free = num_bytes - needed;
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refilled_bytes = needed;
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} else {
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block_rsv->reserved += num_bytes;
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to_free = 0;
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refilled_bytes = num_bytes;
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}
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} else {
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to_free = num_bytes;
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refilled_bytes = 0;
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}
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spin_unlock(&block_rsv->lock);
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if (to_free > 0)
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btrfs_space_info_free_bytes_may_use(fs_info, space_info, to_free);
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if (refilled_bytes > 0)
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trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv", 0,
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refilled_bytes, 1);
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return 0;
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}
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/*
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* compare two delayed data backrefs with same bytenr and type
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*/
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static int comp_data_refs(struct btrfs_delayed_ref_node *ref1,
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struct btrfs_delayed_ref_node *ref2)
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{
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if (ref1->data_ref.objectid < ref2->data_ref.objectid)
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return -1;
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if (ref1->data_ref.objectid > ref2->data_ref.objectid)
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return 1;
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if (ref1->data_ref.offset < ref2->data_ref.offset)
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return -1;
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if (ref1->data_ref.offset > ref2->data_ref.offset)
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return 1;
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return 0;
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}
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static int comp_refs(struct btrfs_delayed_ref_node *ref1,
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struct btrfs_delayed_ref_node *ref2,
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bool check_seq)
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{
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int ret = 0;
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if (ref1->type < ref2->type)
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return -1;
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if (ref1->type > ref2->type)
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return 1;
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if (ref1->type == BTRFS_SHARED_BLOCK_REF_KEY ||
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ref1->type == BTRFS_SHARED_DATA_REF_KEY) {
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if (ref1->parent < ref2->parent)
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return -1;
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if (ref1->parent > ref2->parent)
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return 1;
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} else {
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if (ref1->ref_root < ref2->ref_root)
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return -1;
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if (ref1->ref_root > ref2->ref_root)
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return -1;
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if (ref1->type == BTRFS_EXTENT_DATA_REF_KEY)
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ret = comp_data_refs(ref1, ref2);
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}
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if (ret)
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return ret;
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if (check_seq) {
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if (ref1->seq < ref2->seq)
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return -1;
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if (ref1->seq > ref2->seq)
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return 1;
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}
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return 0;
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}
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/* insert a new ref to head ref rbtree */
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static struct btrfs_delayed_ref_head *htree_insert(struct rb_root_cached *root,
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struct rb_node *node)
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{
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struct rb_node **p = &root->rb_root.rb_node;
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struct rb_node *parent_node = NULL;
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struct btrfs_delayed_ref_head *entry;
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struct btrfs_delayed_ref_head *ins;
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u64 bytenr;
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bool leftmost = true;
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ins = rb_entry(node, struct btrfs_delayed_ref_head, href_node);
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bytenr = ins->bytenr;
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while (*p) {
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parent_node = *p;
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entry = rb_entry(parent_node, struct btrfs_delayed_ref_head,
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href_node);
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if (bytenr < entry->bytenr) {
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p = &(*p)->rb_left;
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} else if (bytenr > entry->bytenr) {
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p = &(*p)->rb_right;
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leftmost = false;
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} else {
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return entry;
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}
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}
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rb_link_node(node, parent_node, p);
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rb_insert_color_cached(node, root, leftmost);
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return NULL;
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}
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static struct btrfs_delayed_ref_node* tree_insert(struct rb_root_cached *root,
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struct btrfs_delayed_ref_node *ins)
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{
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struct rb_node **p = &root->rb_root.rb_node;
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struct rb_node *node = &ins->ref_node;
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struct rb_node *parent_node = NULL;
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struct btrfs_delayed_ref_node *entry;
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bool leftmost = true;
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while (*p) {
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int comp;
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parent_node = *p;
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entry = rb_entry(parent_node, struct btrfs_delayed_ref_node,
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ref_node);
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comp = comp_refs(ins, entry, true);
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if (comp < 0) {
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p = &(*p)->rb_left;
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} else if (comp > 0) {
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p = &(*p)->rb_right;
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leftmost = false;
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} else {
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return entry;
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}
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}
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rb_link_node(node, parent_node, p);
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rb_insert_color_cached(node, root, leftmost);
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return NULL;
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}
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static struct btrfs_delayed_ref_head *find_first_ref_head(
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struct btrfs_delayed_ref_root *dr)
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{
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struct rb_node *n;
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struct btrfs_delayed_ref_head *entry;
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n = rb_first_cached(&dr->href_root);
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if (!n)
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return NULL;
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entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node);
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return entry;
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}
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/*
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* Find a head entry based on bytenr. This returns the delayed ref head if it
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* was able to find one, or NULL if nothing was in that spot. If return_bigger
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* is given, the next bigger entry is returned if no exact match is found.
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*/
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static struct btrfs_delayed_ref_head *find_ref_head(
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struct btrfs_delayed_ref_root *dr, u64 bytenr,
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bool return_bigger)
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{
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struct rb_root *root = &dr->href_root.rb_root;
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struct rb_node *n;
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struct btrfs_delayed_ref_head *entry;
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n = root->rb_node;
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entry = NULL;
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while (n) {
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entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node);
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if (bytenr < entry->bytenr)
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n = n->rb_left;
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else if (bytenr > entry->bytenr)
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n = n->rb_right;
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else
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return entry;
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}
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if (entry && return_bigger) {
|
|
if (bytenr > entry->bytenr) {
|
|
n = rb_next(&entry->href_node);
|
|
if (!n)
|
|
return NULL;
|
|
entry = rb_entry(n, struct btrfs_delayed_ref_head,
|
|
href_node);
|
|
}
|
|
return entry;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
int btrfs_delayed_ref_lock(struct btrfs_delayed_ref_root *delayed_refs,
|
|
struct btrfs_delayed_ref_head *head)
|
|
{
|
|
lockdep_assert_held(&delayed_refs->lock);
|
|
if (mutex_trylock(&head->mutex))
|
|
return 0;
|
|
|
|
refcount_inc(&head->refs);
|
|
spin_unlock(&delayed_refs->lock);
|
|
|
|
mutex_lock(&head->mutex);
|
|
spin_lock(&delayed_refs->lock);
|
|
if (RB_EMPTY_NODE(&head->href_node)) {
|
|
mutex_unlock(&head->mutex);
|
|
btrfs_put_delayed_ref_head(head);
|
|
return -EAGAIN;
|
|
}
|
|
btrfs_put_delayed_ref_head(head);
|
|
return 0;
|
|
}
|
|
|
|
static inline void drop_delayed_ref(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_delayed_ref_root *delayed_refs,
|
|
struct btrfs_delayed_ref_head *head,
|
|
struct btrfs_delayed_ref_node *ref)
|
|
{
|
|
lockdep_assert_held(&head->lock);
|
|
rb_erase_cached(&ref->ref_node, &head->ref_tree);
|
|
RB_CLEAR_NODE(&ref->ref_node);
|
|
if (!list_empty(&ref->add_list))
|
|
list_del(&ref->add_list);
|
|
btrfs_put_delayed_ref(ref);
|
|
atomic_dec(&delayed_refs->num_entries);
|
|
btrfs_delayed_refs_rsv_release(fs_info, 1, 0);
|
|
}
|
|
|
|
static bool merge_ref(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_delayed_ref_root *delayed_refs,
|
|
struct btrfs_delayed_ref_head *head,
|
|
struct btrfs_delayed_ref_node *ref,
|
|
u64 seq)
|
|
{
|
|
struct btrfs_delayed_ref_node *next;
|
|
struct rb_node *node = rb_next(&ref->ref_node);
|
|
bool done = false;
|
|
|
|
while (!done && node) {
|
|
int mod;
|
|
|
|
next = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
|
|
node = rb_next(node);
|
|
if (seq && next->seq >= seq)
|
|
break;
|
|
if (comp_refs(ref, next, false))
|
|
break;
|
|
|
|
if (ref->action == next->action) {
|
|
mod = next->ref_mod;
|
|
} else {
|
|
if (ref->ref_mod < next->ref_mod) {
|
|
swap(ref, next);
|
|
done = true;
|
|
}
|
|
mod = -next->ref_mod;
|
|
}
|
|
|
|
drop_delayed_ref(fs_info, delayed_refs, head, next);
|
|
ref->ref_mod += mod;
|
|
if (ref->ref_mod == 0) {
|
|
drop_delayed_ref(fs_info, delayed_refs, head, ref);
|
|
done = true;
|
|
} else {
|
|
/*
|
|
* Can't have multiples of the same ref on a tree block.
|
|
*/
|
|
WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY ||
|
|
ref->type == BTRFS_SHARED_BLOCK_REF_KEY);
|
|
}
|
|
}
|
|
|
|
return done;
|
|
}
|
|
|
|
void btrfs_merge_delayed_refs(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_delayed_ref_root *delayed_refs,
|
|
struct btrfs_delayed_ref_head *head)
|
|
{
|
|
struct btrfs_delayed_ref_node *ref;
|
|
struct rb_node *node;
|
|
u64 seq = 0;
|
|
|
|
lockdep_assert_held(&head->lock);
|
|
|
|
if (RB_EMPTY_ROOT(&head->ref_tree.rb_root))
|
|
return;
|
|
|
|
/* We don't have too many refs to merge for data. */
|
|
if (head->is_data)
|
|
return;
|
|
|
|
seq = btrfs_tree_mod_log_lowest_seq(fs_info);
|
|
again:
|
|
for (node = rb_first_cached(&head->ref_tree); node;
|
|
node = rb_next(node)) {
|
|
ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
|
|
if (seq && ref->seq >= seq)
|
|
continue;
|
|
if (merge_ref(fs_info, delayed_refs, head, ref, seq))
|
|
goto again;
|
|
}
|
|
}
|
|
|
|
int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, u64 seq)
|
|
{
|
|
int ret = 0;
|
|
u64 min_seq = btrfs_tree_mod_log_lowest_seq(fs_info);
|
|
|
|
if (min_seq != 0 && seq >= min_seq) {
|
|
btrfs_debug(fs_info,
|
|
"holding back delayed_ref %llu, lowest is %llu",
|
|
seq, min_seq);
|
|
ret = 1;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
struct btrfs_delayed_ref_head *btrfs_select_ref_head(
|
|
struct btrfs_delayed_ref_root *delayed_refs)
|
|
{
|
|
struct btrfs_delayed_ref_head *head;
|
|
|
|
lockdep_assert_held(&delayed_refs->lock);
|
|
again:
|
|
head = find_ref_head(delayed_refs, delayed_refs->run_delayed_start,
|
|
true);
|
|
if (!head && delayed_refs->run_delayed_start != 0) {
|
|
delayed_refs->run_delayed_start = 0;
|
|
head = find_first_ref_head(delayed_refs);
|
|
}
|
|
if (!head)
|
|
return NULL;
|
|
|
|
while (head->processing) {
|
|
struct rb_node *node;
|
|
|
|
node = rb_next(&head->href_node);
|
|
if (!node) {
|
|
if (delayed_refs->run_delayed_start == 0)
|
|
return NULL;
|
|
delayed_refs->run_delayed_start = 0;
|
|
goto again;
|
|
}
|
|
head = rb_entry(node, struct btrfs_delayed_ref_head,
|
|
href_node);
|
|
}
|
|
|
|
head->processing = true;
|
|
WARN_ON(delayed_refs->num_heads_ready == 0);
|
|
delayed_refs->num_heads_ready--;
|
|
delayed_refs->run_delayed_start = head->bytenr +
|
|
head->num_bytes;
|
|
return head;
|
|
}
|
|
|
|
void btrfs_delete_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
|
|
struct btrfs_delayed_ref_head *head)
|
|
{
|
|
lockdep_assert_held(&delayed_refs->lock);
|
|
lockdep_assert_held(&head->lock);
|
|
|
|
rb_erase_cached(&head->href_node, &delayed_refs->href_root);
|
|
RB_CLEAR_NODE(&head->href_node);
|
|
atomic_dec(&delayed_refs->num_entries);
|
|
delayed_refs->num_heads--;
|
|
if (!head->processing)
|
|
delayed_refs->num_heads_ready--;
|
|
}
|
|
|
|
/*
|
|
* Helper to insert the ref_node to the tail or merge with tail.
|
|
*
|
|
* Return false if the ref was inserted.
|
|
* Return true if the ref was merged into an existing one (and therefore can be
|
|
* freed by the caller).
|
|
*/
|
|
static bool insert_delayed_ref(struct btrfs_trans_handle *trans,
|
|
struct btrfs_delayed_ref_head *href,
|
|
struct btrfs_delayed_ref_node *ref)
|
|
{
|
|
struct btrfs_delayed_ref_root *root = &trans->transaction->delayed_refs;
|
|
struct btrfs_delayed_ref_node *exist;
|
|
int mod;
|
|
|
|
spin_lock(&href->lock);
|
|
exist = tree_insert(&href->ref_tree, ref);
|
|
if (!exist) {
|
|
if (ref->action == BTRFS_ADD_DELAYED_REF)
|
|
list_add_tail(&ref->add_list, &href->ref_add_list);
|
|
atomic_inc(&root->num_entries);
|
|
spin_unlock(&href->lock);
|
|
trans->delayed_ref_updates++;
|
|
return false;
|
|
}
|
|
|
|
/* Now we are sure we can merge */
|
|
if (exist->action == ref->action) {
|
|
mod = ref->ref_mod;
|
|
} else {
|
|
/* Need to change action */
|
|
if (exist->ref_mod < ref->ref_mod) {
|
|
exist->action = ref->action;
|
|
mod = -exist->ref_mod;
|
|
exist->ref_mod = ref->ref_mod;
|
|
if (ref->action == BTRFS_ADD_DELAYED_REF)
|
|
list_add_tail(&exist->add_list,
|
|
&href->ref_add_list);
|
|
else if (ref->action == BTRFS_DROP_DELAYED_REF) {
|
|
ASSERT(!list_empty(&exist->add_list));
|
|
list_del(&exist->add_list);
|
|
} else {
|
|
ASSERT(0);
|
|
}
|
|
} else
|
|
mod = -ref->ref_mod;
|
|
}
|
|
exist->ref_mod += mod;
|
|
|
|
/* remove existing tail if its ref_mod is zero */
|
|
if (exist->ref_mod == 0)
|
|
drop_delayed_ref(trans->fs_info, root, href, exist);
|
|
spin_unlock(&href->lock);
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* helper function to update the accounting in the head ref
|
|
* existing and update must have the same bytenr
|
|
*/
|
|
static noinline void update_existing_head_ref(struct btrfs_trans_handle *trans,
|
|
struct btrfs_delayed_ref_head *existing,
|
|
struct btrfs_delayed_ref_head *update)
|
|
{
|
|
struct btrfs_delayed_ref_root *delayed_refs =
|
|
&trans->transaction->delayed_refs;
|
|
struct btrfs_fs_info *fs_info = trans->fs_info;
|
|
int old_ref_mod;
|
|
|
|
BUG_ON(existing->is_data != update->is_data);
|
|
|
|
spin_lock(&existing->lock);
|
|
|
|
/*
|
|
* When freeing an extent, we may not know the owning root when we
|
|
* first create the head_ref. However, some deref before the last deref
|
|
* will know it, so we just need to update the head_ref accordingly.
|
|
*/
|
|
if (!existing->owning_root)
|
|
existing->owning_root = update->owning_root;
|
|
|
|
if (update->must_insert_reserved) {
|
|
/* if the extent was freed and then
|
|
* reallocated before the delayed ref
|
|
* entries were processed, we can end up
|
|
* with an existing head ref without
|
|
* the must_insert_reserved flag set.
|
|
* Set it again here
|
|
*/
|
|
existing->must_insert_reserved = update->must_insert_reserved;
|
|
existing->owning_root = update->owning_root;
|
|
|
|
/*
|
|
* update the num_bytes so we make sure the accounting
|
|
* is done correctly
|
|
*/
|
|
existing->num_bytes = update->num_bytes;
|
|
|
|
}
|
|
|
|
if (update->extent_op) {
|
|
if (!existing->extent_op) {
|
|
existing->extent_op = update->extent_op;
|
|
} else {
|
|
if (update->extent_op->update_key) {
|
|
memcpy(&existing->extent_op->key,
|
|
&update->extent_op->key,
|
|
sizeof(update->extent_op->key));
|
|
existing->extent_op->update_key = true;
|
|
}
|
|
if (update->extent_op->update_flags) {
|
|
existing->extent_op->flags_to_set |=
|
|
update->extent_op->flags_to_set;
|
|
existing->extent_op->update_flags = true;
|
|
}
|
|
btrfs_free_delayed_extent_op(update->extent_op);
|
|
}
|
|
}
|
|
/*
|
|
* update the reference mod on the head to reflect this new operation,
|
|
* only need the lock for this case cause we could be processing it
|
|
* currently, for refs we just added we know we're a-ok.
|
|
*/
|
|
old_ref_mod = existing->total_ref_mod;
|
|
existing->ref_mod += update->ref_mod;
|
|
existing->total_ref_mod += update->ref_mod;
|
|
|
|
/*
|
|
* If we are going to from a positive ref mod to a negative or vice
|
|
* versa we need to make sure to adjust pending_csums accordingly.
|
|
* We reserve bytes for csum deletion when adding or updating a ref head
|
|
* see add_delayed_ref_head() for more details.
|
|
*/
|
|
if (existing->is_data) {
|
|
u64 csum_leaves =
|
|
btrfs_csum_bytes_to_leaves(fs_info,
|
|
existing->num_bytes);
|
|
|
|
if (existing->total_ref_mod >= 0 && old_ref_mod < 0) {
|
|
delayed_refs->pending_csums -= existing->num_bytes;
|
|
btrfs_delayed_refs_rsv_release(fs_info, 0, csum_leaves);
|
|
}
|
|
if (existing->total_ref_mod < 0 && old_ref_mod >= 0) {
|
|
delayed_refs->pending_csums += existing->num_bytes;
|
|
trans->delayed_ref_csum_deletions += csum_leaves;
|
|
}
|
|
}
|
|
|
|
spin_unlock(&existing->lock);
|
|
}
|
|
|
|
static void init_delayed_ref_head(struct btrfs_delayed_ref_head *head_ref,
|
|
struct btrfs_ref *generic_ref,
|
|
struct btrfs_qgroup_extent_record *qrecord,
|
|
u64 reserved)
|
|
{
|
|
int count_mod = 1;
|
|
bool must_insert_reserved = false;
|
|
|
|
/* If reserved is provided, it must be a data extent. */
|
|
BUG_ON(generic_ref->type != BTRFS_REF_DATA && reserved);
|
|
|
|
switch (generic_ref->action) {
|
|
case BTRFS_ADD_DELAYED_REF:
|
|
/* count_mod is already set to 1. */
|
|
break;
|
|
case BTRFS_UPDATE_DELAYED_HEAD:
|
|
count_mod = 0;
|
|
break;
|
|
case BTRFS_DROP_DELAYED_REF:
|
|
/*
|
|
* The head node stores the sum of all the mods, so dropping a ref
|
|
* should drop the sum in the head node by one.
|
|
*/
|
|
count_mod = -1;
|
|
break;
|
|
case BTRFS_ADD_DELAYED_EXTENT:
|
|
/*
|
|
* BTRFS_ADD_DELAYED_EXTENT means that we need to update the
|
|
* reserved accounting when the extent is finally added, or if a
|
|
* later modification deletes the delayed ref without ever
|
|
* inserting the extent into the extent allocation tree.
|
|
* ref->must_insert_reserved is the flag used to record that
|
|
* accounting mods are required.
|
|
*
|
|
* Once we record must_insert_reserved, switch the action to
|
|
* BTRFS_ADD_DELAYED_REF because other special casing is not
|
|
* required.
|
|
*/
|
|
must_insert_reserved = true;
|
|
break;
|
|
}
|
|
|
|
refcount_set(&head_ref->refs, 1);
|
|
head_ref->bytenr = generic_ref->bytenr;
|
|
head_ref->num_bytes = generic_ref->num_bytes;
|
|
head_ref->ref_mod = count_mod;
|
|
head_ref->reserved_bytes = reserved;
|
|
head_ref->must_insert_reserved = must_insert_reserved;
|
|
head_ref->owning_root = generic_ref->owning_root;
|
|
head_ref->is_data = (generic_ref->type == BTRFS_REF_DATA);
|
|
head_ref->is_system = (generic_ref->ref_root == BTRFS_CHUNK_TREE_OBJECTID);
|
|
head_ref->ref_tree = RB_ROOT_CACHED;
|
|
INIT_LIST_HEAD(&head_ref->ref_add_list);
|
|
RB_CLEAR_NODE(&head_ref->href_node);
|
|
head_ref->processing = false;
|
|
head_ref->total_ref_mod = count_mod;
|
|
spin_lock_init(&head_ref->lock);
|
|
mutex_init(&head_ref->mutex);
|
|
|
|
if (qrecord) {
|
|
if (generic_ref->ref_root && reserved) {
|
|
qrecord->data_rsv = reserved;
|
|
qrecord->data_rsv_refroot = generic_ref->ref_root;
|
|
}
|
|
qrecord->bytenr = generic_ref->bytenr;
|
|
qrecord->num_bytes = generic_ref->num_bytes;
|
|
qrecord->old_roots = NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* helper function to actually insert a head node into the rbtree.
|
|
* this does all the dirty work in terms of maintaining the correct
|
|
* overall modification count.
|
|
*/
|
|
static noinline struct btrfs_delayed_ref_head *
|
|
add_delayed_ref_head(struct btrfs_trans_handle *trans,
|
|
struct btrfs_delayed_ref_head *head_ref,
|
|
struct btrfs_qgroup_extent_record *qrecord,
|
|
int action, bool *qrecord_inserted_ret)
|
|
{
|
|
struct btrfs_delayed_ref_head *existing;
|
|
struct btrfs_delayed_ref_root *delayed_refs;
|
|
bool qrecord_inserted = false;
|
|
|
|
delayed_refs = &trans->transaction->delayed_refs;
|
|
|
|
/* Record qgroup extent info if provided */
|
|
if (qrecord) {
|
|
if (btrfs_qgroup_trace_extent_nolock(trans->fs_info,
|
|
delayed_refs, qrecord))
|
|
kfree(qrecord);
|
|
else
|
|
qrecord_inserted = true;
|
|
}
|
|
|
|
trace_add_delayed_ref_head(trans->fs_info, head_ref, action);
|
|
|
|
existing = htree_insert(&delayed_refs->href_root,
|
|
&head_ref->href_node);
|
|
if (existing) {
|
|
update_existing_head_ref(trans, existing, head_ref);
|
|
/*
|
|
* we've updated the existing ref, free the newly
|
|
* allocated ref
|
|
*/
|
|
kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
|
|
head_ref = existing;
|
|
} else {
|
|
/*
|
|
* We reserve the amount of bytes needed to delete csums when
|
|
* adding the ref head and not when adding individual drop refs
|
|
* since the csum items are deleted only after running the last
|
|
* delayed drop ref (the data extent's ref count drops to 0).
|
|
*/
|
|
if (head_ref->is_data && head_ref->ref_mod < 0) {
|
|
delayed_refs->pending_csums += head_ref->num_bytes;
|
|
trans->delayed_ref_csum_deletions +=
|
|
btrfs_csum_bytes_to_leaves(trans->fs_info,
|
|
head_ref->num_bytes);
|
|
}
|
|
delayed_refs->num_heads++;
|
|
delayed_refs->num_heads_ready++;
|
|
atomic_inc(&delayed_refs->num_entries);
|
|
}
|
|
if (qrecord_inserted_ret)
|
|
*qrecord_inserted_ret = qrecord_inserted;
|
|
|
|
return head_ref;
|
|
}
|
|
|
|
/*
|
|
* Initialize the structure which represents a modification to a an extent.
|
|
*
|
|
* @fs_info: Internal to the mounted filesystem mount structure.
|
|
*
|
|
* @ref: The structure which is going to be initialized.
|
|
*
|
|
* @bytenr: The logical address of the extent for which a modification is
|
|
* going to be recorded.
|
|
*
|
|
* @num_bytes: Size of the extent whose modification is being recorded.
|
|
*
|
|
* @ref_root: The id of the root where this modification has originated, this
|
|
* can be either one of the well-known metadata trees or the
|
|
* subvolume id which references this extent.
|
|
*
|
|
* @action: Can be one of BTRFS_ADD_DELAYED_REF/BTRFS_DROP_DELAYED_REF or
|
|
* BTRFS_ADD_DELAYED_EXTENT
|
|
*
|
|
* @ref_type: Holds the type of the extent which is being recorded, can be
|
|
* one of BTRFS_SHARED_BLOCK_REF_KEY/BTRFS_TREE_BLOCK_REF_KEY
|
|
* when recording a metadata extent or BTRFS_SHARED_DATA_REF_KEY/
|
|
* BTRFS_EXTENT_DATA_REF_KEY when recording data extent
|
|
*/
|
|
static void init_delayed_ref_common(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_delayed_ref_node *ref,
|
|
struct btrfs_ref *generic_ref)
|
|
{
|
|
int action = generic_ref->action;
|
|
u64 seq = 0;
|
|
|
|
if (action == BTRFS_ADD_DELAYED_EXTENT)
|
|
action = BTRFS_ADD_DELAYED_REF;
|
|
|
|
if (is_fstree(generic_ref->ref_root))
|
|
seq = atomic64_read(&fs_info->tree_mod_seq);
|
|
|
|
refcount_set(&ref->refs, 1);
|
|
ref->bytenr = generic_ref->bytenr;
|
|
ref->num_bytes = generic_ref->num_bytes;
|
|
ref->ref_mod = 1;
|
|
ref->action = action;
|
|
ref->seq = seq;
|
|
ref->type = btrfs_ref_type(generic_ref);
|
|
ref->ref_root = generic_ref->ref_root;
|
|
ref->parent = generic_ref->parent;
|
|
RB_CLEAR_NODE(&ref->ref_node);
|
|
INIT_LIST_HEAD(&ref->add_list);
|
|
|
|
if (generic_ref->type == BTRFS_REF_DATA)
|
|
ref->data_ref = generic_ref->data_ref;
|
|
else
|
|
ref->tree_ref = generic_ref->tree_ref;
|
|
}
|
|
|
|
void btrfs_init_tree_ref(struct btrfs_ref *generic_ref, int level, u64 mod_root,
|
|
bool skip_qgroup)
|
|
{
|
|
#ifdef CONFIG_BTRFS_FS_REF_VERIFY
|
|
/* If @real_root not set, use @root as fallback */
|
|
generic_ref->real_root = mod_root ?: generic_ref->ref_root;
|
|
#endif
|
|
generic_ref->tree_ref.level = level;
|
|
generic_ref->type = BTRFS_REF_METADATA;
|
|
if (skip_qgroup || !(is_fstree(generic_ref->ref_root) &&
|
|
(!mod_root || is_fstree(mod_root))))
|
|
generic_ref->skip_qgroup = true;
|
|
else
|
|
generic_ref->skip_qgroup = false;
|
|
|
|
}
|
|
|
|
void btrfs_init_data_ref(struct btrfs_ref *generic_ref, u64 ino, u64 offset,
|
|
u64 mod_root, bool skip_qgroup)
|
|
{
|
|
#ifdef CONFIG_BTRFS_FS_REF_VERIFY
|
|
/* If @real_root not set, use @root as fallback */
|
|
generic_ref->real_root = mod_root ?: generic_ref->ref_root;
|
|
#endif
|
|
generic_ref->data_ref.objectid = ino;
|
|
generic_ref->data_ref.offset = offset;
|
|
generic_ref->type = BTRFS_REF_DATA;
|
|
if (skip_qgroup || !(is_fstree(generic_ref->ref_root) &&
|
|
(!mod_root || is_fstree(mod_root))))
|
|
generic_ref->skip_qgroup = true;
|
|
else
|
|
generic_ref->skip_qgroup = false;
|
|
}
|
|
|
|
static int add_delayed_ref(struct btrfs_trans_handle *trans,
|
|
struct btrfs_ref *generic_ref,
|
|
struct btrfs_delayed_extent_op *extent_op,
|
|
u64 reserved)
|
|
{
|
|
struct btrfs_fs_info *fs_info = trans->fs_info;
|
|
struct btrfs_delayed_ref_node *node;
|
|
struct btrfs_delayed_ref_head *head_ref;
|
|
struct btrfs_delayed_ref_root *delayed_refs;
|
|
struct btrfs_qgroup_extent_record *record = NULL;
|
|
bool qrecord_inserted;
|
|
int action = generic_ref->action;
|
|
bool merged;
|
|
|
|
node = kmem_cache_alloc(btrfs_delayed_ref_node_cachep, GFP_NOFS);
|
|
if (!node)
|
|
return -ENOMEM;
|
|
|
|
head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
|
|
if (!head_ref) {
|
|
kmem_cache_free(btrfs_delayed_ref_node_cachep, node);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (btrfs_qgroup_full_accounting(fs_info) && !generic_ref->skip_qgroup) {
|
|
record = kzalloc(sizeof(*record), GFP_NOFS);
|
|
if (!record) {
|
|
kmem_cache_free(btrfs_delayed_ref_node_cachep, node);
|
|
kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
|
|
init_delayed_ref_common(fs_info, node, generic_ref);
|
|
init_delayed_ref_head(head_ref, generic_ref, record, reserved);
|
|
head_ref->extent_op = extent_op;
|
|
|
|
delayed_refs = &trans->transaction->delayed_refs;
|
|
spin_lock(&delayed_refs->lock);
|
|
|
|
/*
|
|
* insert both the head node and the new ref without dropping
|
|
* the spin lock
|
|
*/
|
|
head_ref = add_delayed_ref_head(trans, head_ref, record,
|
|
action, &qrecord_inserted);
|
|
|
|
merged = insert_delayed_ref(trans, head_ref, node);
|
|
spin_unlock(&delayed_refs->lock);
|
|
|
|
/*
|
|
* Need to update the delayed_refs_rsv with any changes we may have
|
|
* made.
|
|
*/
|
|
btrfs_update_delayed_refs_rsv(trans);
|
|
|
|
if (generic_ref->type == BTRFS_REF_DATA)
|
|
trace_add_delayed_data_ref(trans->fs_info, node);
|
|
else
|
|
trace_add_delayed_tree_ref(trans->fs_info, node);
|
|
if (merged)
|
|
kmem_cache_free(btrfs_delayed_ref_node_cachep, node);
|
|
|
|
if (qrecord_inserted)
|
|
return btrfs_qgroup_trace_extent_post(trans, record);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Add a delayed tree ref. This does all of the accounting required to make sure
|
|
* the delayed ref is eventually processed before this transaction commits.
|
|
*/
|
|
int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
|
|
struct btrfs_ref *generic_ref,
|
|
struct btrfs_delayed_extent_op *extent_op)
|
|
{
|
|
ASSERT(generic_ref->type == BTRFS_REF_METADATA && generic_ref->action);
|
|
return add_delayed_ref(trans, generic_ref, extent_op, 0);
|
|
}
|
|
|
|
/*
|
|
* add a delayed data ref. it's similar to btrfs_add_delayed_tree_ref.
|
|
*/
|
|
int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans,
|
|
struct btrfs_ref *generic_ref,
|
|
u64 reserved)
|
|
{
|
|
ASSERT(generic_ref->type == BTRFS_REF_DATA && generic_ref->action);
|
|
return add_delayed_ref(trans, generic_ref, NULL, reserved);
|
|
}
|
|
|
|
int btrfs_add_delayed_extent_op(struct btrfs_trans_handle *trans,
|
|
u64 bytenr, u64 num_bytes,
|
|
struct btrfs_delayed_extent_op *extent_op)
|
|
{
|
|
struct btrfs_delayed_ref_head *head_ref;
|
|
struct btrfs_delayed_ref_root *delayed_refs;
|
|
struct btrfs_ref generic_ref = {
|
|
.type = BTRFS_REF_METADATA,
|
|
.action = BTRFS_UPDATE_DELAYED_HEAD,
|
|
.bytenr = bytenr,
|
|
.num_bytes = num_bytes,
|
|
};
|
|
|
|
head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
|
|
if (!head_ref)
|
|
return -ENOMEM;
|
|
|
|
init_delayed_ref_head(head_ref, &generic_ref, NULL, 0);
|
|
head_ref->extent_op = extent_op;
|
|
|
|
delayed_refs = &trans->transaction->delayed_refs;
|
|
spin_lock(&delayed_refs->lock);
|
|
|
|
add_delayed_ref_head(trans, head_ref, NULL, BTRFS_UPDATE_DELAYED_HEAD,
|
|
NULL);
|
|
|
|
spin_unlock(&delayed_refs->lock);
|
|
|
|
/*
|
|
* Need to update the delayed_refs_rsv with any changes we may have
|
|
* made.
|
|
*/
|
|
btrfs_update_delayed_refs_rsv(trans);
|
|
return 0;
|
|
}
|
|
|
|
void btrfs_put_delayed_ref(struct btrfs_delayed_ref_node *ref)
|
|
{
|
|
if (refcount_dec_and_test(&ref->refs)) {
|
|
WARN_ON(!RB_EMPTY_NODE(&ref->ref_node));
|
|
kmem_cache_free(btrfs_delayed_ref_node_cachep, ref);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This does a simple search for the head node for a given extent. Returns the
|
|
* head node if found, or NULL if not.
|
|
*/
|
|
struct btrfs_delayed_ref_head *
|
|
btrfs_find_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs, u64 bytenr)
|
|
{
|
|
lockdep_assert_held(&delayed_refs->lock);
|
|
|
|
return find_ref_head(delayed_refs, bytenr, false);
|
|
}
|
|
|
|
void __cold btrfs_delayed_ref_exit(void)
|
|
{
|
|
kmem_cache_destroy(btrfs_delayed_ref_head_cachep);
|
|
kmem_cache_destroy(btrfs_delayed_ref_node_cachep);
|
|
kmem_cache_destroy(btrfs_delayed_extent_op_cachep);
|
|
}
|
|
|
|
int __init btrfs_delayed_ref_init(void)
|
|
{
|
|
btrfs_delayed_ref_head_cachep = KMEM_CACHE(btrfs_delayed_ref_head, 0);
|
|
if (!btrfs_delayed_ref_head_cachep)
|
|
goto fail;
|
|
|
|
btrfs_delayed_ref_node_cachep = KMEM_CACHE(btrfs_delayed_ref_node, 0);
|
|
if (!btrfs_delayed_ref_node_cachep)
|
|
goto fail;
|
|
|
|
btrfs_delayed_extent_op_cachep = KMEM_CACHE(btrfs_delayed_extent_op, 0);
|
|
if (!btrfs_delayed_extent_op_cachep)
|
|
goto fail;
|
|
|
|
return 0;
|
|
fail:
|
|
btrfs_delayed_ref_exit();
|
|
return -ENOMEM;
|
|
}
|