ceph/src/crimson/os/seastore/lba_manager/btree/btree_lba_manager.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #pragma once
   5
   6 #include <iostream>
   7
   8 #include <boost/intrusive_ptr.hpp>
   9 #include <boost/smart_ptr/intrusive_ref_counter.hpp>
  10 #include <seastar/core/future.hh>
  11
  12 #include "include/ceph_assert.h"
  13 #include "include/buffer_fwd.h"
  14 #include "include/interval_set.h"
  15 #include "common/interval_map.h"
  16 #include "crimson/osd/exceptions.h"
  17
  18 #include "crimson/os/seastore/btree/fixed_kv_btree.h"
  19 #include "crimson/os/seastore/seastore_types.h"
  20 #include "crimson/os/seastore/lba_manager.h"
  21 #include "crimson/os/seastore/cache.h"
  22
  23 #include "crimson/os/seastore/lba_manager/btree/lba_btree_node.h"
  24 #include "crimson/os/seastore/btree/btree_range_pin.h"
  25
  26 namespace crimson::os::seastore::lba_manager::btree {
  27
  28 class BtreeLBAMapping : public BtreeNodeMapping<laddr_t, paddr_t> {
  29 public:
  30   BtreeLBAMapping(op_context_t<laddr_t> ctx)
  31     : BtreeNodeMapping(ctx) {}
  32   BtreeLBAMapping(
  33     op_context_t<laddr_t> c,
  34     CachedExtentRef parent,
  35     uint16_t pos,
  36     lba_map_val_t &val,
  37     lba_node_meta_t &&meta)
  38     : BtreeNodeMapping(
  39         c,
  40         parent,
  41         pos,
  42         val.paddr,
  43         val.len,
  44         std::forward<lba_node_meta_t>(meta))
  45   {}
  46 };
  47
  48 using LBABtree = FixedKVBtree<
  49   laddr_t, lba_map_val_t, LBAInternalNode,
  50   LBALeafNode, BtreeLBAMapping, LBA_BLOCK_SIZE, true>;
  51
  52 /**
  53  * BtreeLBAManager
  54  *
  55  * Uses a wandering btree to track two things:
  56  * 1) lba state including laddr_t -> paddr_t mapping
  57  * 2) reverse paddr_t -> laddr_t mapping for gc (TODO)
  58  *
  59  * Generally, any transaction will involve
  60  * 1) deltas against lba tree nodes
  61  * 2) new lba tree nodes
  62  *    - Note, there must necessarily be a delta linking
  63  *      these new nodes into the tree -- might be a
  64  *      bootstrap_state_t delta if new root
  65  *
  66  * get_mappings, alloc_extent_*, etc populate a Transaction
  67  * which then gets submitted
  68  */
  69 class BtreeLBAManager : public LBAManager {
  70 public:
  71   BtreeLBAManager(Cache &cache)
  72     : cache(cache)
  73   {
  74     register_metrics();
  75   }
  76
  77   mkfs_ret mkfs(
  78     Transaction &t) final;
  79
  80   get_mappings_ret get_mappings(
  81     Transaction &t,
  82     laddr_t offset, extent_len_t length) final;
  83
  84   get_mappings_ret get_mappings(
  85     Transaction &t,
  86     laddr_list_t &&list) final;
  87
  88   get_mapping_ret get_mapping(
  89     Transaction &t,
  90     laddr_t offset) final;
  91
  92   alloc_extent_ret alloc_extent(
  93     Transaction &t,
  94     laddr_t hint,
  95     extent_len_t len,
  96     paddr_t addr,
  97     LogicalCachedExtent*) final;
  98
  99   ref_ret decref_extent(
 100     Transaction &t,
 101     laddr_t addr) final {
 102     return update_refcount(t, addr, -1);
 103   }
 104
 105   ref_ret incref_extent(
 106     Transaction &t,
 107     laddr_t addr) final {
 108     return update_refcount(t, addr, 1);
 109   }
 110
 111   /**
 112    * init_cached_extent
 113    *
 114    * Checks whether e is live (reachable from lba tree) and drops or initializes
 115    * accordingly.
 116    *
 117    * Returns if e is live.
 118    */
 119   init_cached_extent_ret init_cached_extent(
 120     Transaction &t,
 121     CachedExtentRef e) final;
 122
 123   check_child_trackers_ret check_child_trackers(Transaction &t) final;
 124
 125   scan_mappings_ret scan_mappings(
 126     Transaction &t,
 127     laddr_t begin,
 128     laddr_t end,
 129     scan_mappings_func_t &&f) final;
 130
 131   rewrite_extent_ret rewrite_extent(
 132     Transaction &t,
 133     CachedExtentRef extent) final;
 134
 135   update_mapping_ret update_mapping(
 136     Transaction& t,
 137     laddr_t laddr,
 138     paddr_t prev_addr,
 139     paddr_t paddr,
 140     LogicalCachedExtent*) final;
 141
 142   get_physical_extent_if_live_ret get_physical_extent_if_live(
 143     Transaction &t,
 144     extent_types_t type,
 145     paddr_t addr,
 146     laddr_t laddr,
 147     extent_len_t len) final;
 148 private:
 149   Cache &cache;
 150
 151
 152   struct {
 153     uint64_t num_alloc_extents = 0;
 154     uint64_t num_alloc_extents_iter_nexts = 0;
 155   } stats;
 156
 157   op_context_t<laddr_t> get_context(Transaction &t) {
 158     return op_context_t<laddr_t>{cache, t};
 159   }
 160
 161   seastar::metrics::metric_group metrics;
 162   void register_metrics();
 163
 164   /**
 165    * update_refcount
 166    *
 167    * Updates refcount, returns resulting refcount
 168    */
 169   using update_refcount_ret = ref_ret;
 170   update_refcount_ret update_refcount(
 171     Transaction &t,
 172     laddr_t addr,
 173     int delta);
 174
 175   /**
 176    * _update_mapping
 177    *
 178    * Updates mapping, removes if f returns nullopt
 179    */
 180   using _update_mapping_iertr = ref_iertr;
 181   using _update_mapping_ret = ref_iertr::future<lba_map_val_t>;
 182   using update_func_t = std::function<
 183     lba_map_val_t(const lba_map_val_t &v)
 184     >;
 185   _update_mapping_ret _update_mapping(
 186     Transaction &t,
 187     laddr_t addr,
 188     update_func_t &&f,
 189     LogicalCachedExtent*);
 190 };
 191 using BtreeLBAManagerRef = std::unique_ptr<BtreeLBAManager>;
 192
 193 }