fs/btrfs/free-space-cache.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (C) 2009 Oracle.  All rights reserved.
   4  */
   5
   6 #ifndef BTRFS_FREE_SPACE_CACHE_H
   7 #define BTRFS_FREE_SPACE_CACHE_H
   8
   9 #include <linux/rbtree.h>
  10 #include <linux/list.h>
  11 #include <linux/spinlock.h>
  12 #include <linux/mutex.h>
  13 #include <linux/freezer.h>
  14 #include "fs.h"
  15
  16 struct inode;
  17 struct page;
  18 struct btrfs_fs_info;
  19 struct btrfs_path;
  20 struct btrfs_trans_handle;
  21 struct btrfs_trim_block_group;
  22
  23 /*
  24  * This is the trim state of an extent or bitmap.
  25  *
  26  * BTRFS_TRIM_STATE_TRIMMING is special and used to maintain the state of a
  27  * bitmap as we may need several trims to fully trim a single bitmap entry.
  28  * This is reset should any free space other than trimmed space be added to the
  29  * bitmap.
  30  */
  31 enum btrfs_trim_state {
  32         BTRFS_TRIM_STATE_UNTRIMMED,
  33         BTRFS_TRIM_STATE_TRIMMED,
  34         BTRFS_TRIM_STATE_TRIMMING,
  35 };
  36
  37 struct btrfs_free_space {
  38         struct rb_node offset_index;
  39         struct rb_node bytes_index;
  40         u64 offset;
  41         u64 bytes;
  42         u64 max_extent_size;
  43         unsigned long *bitmap;
  44         struct list_head list;
  45         enum btrfs_trim_state trim_state;
  46         s32 bitmap_extents;
  47 };
  48
  49 static inline bool btrfs_free_space_trimmed(struct btrfs_free_space *info)
  50 {
  51         return (info->trim_state == BTRFS_TRIM_STATE_TRIMMED);
  52 }
  53
  54 static inline bool btrfs_free_space_trimming_bitmap(
  55                                             struct btrfs_free_space *info)
  56 {
  57         return (info->trim_state == BTRFS_TRIM_STATE_TRIMMING);
  58 }
  59
  60 static inline bool btrfs_trim_interrupted(void)
  61 {
  62         return fatal_signal_pending(current) || freezing(current);
  63 }
  64
  65 /*
  66  * Deltas are an effective way to populate global statistics.  Give macro names
  67  * to make it clear what we're doing.  An example is discard_extents in
  68  * btrfs_free_space_ctl.
  69  */
  70 enum {
  71         BTRFS_STAT_CURR,
  72         BTRFS_STAT_PREV,
  73         BTRFS_STAT_NR_ENTRIES,
  74 };
  75
  76 struct btrfs_free_space_ctl {
  77         spinlock_t tree_lock;
  78         struct rb_root free_space_offset;
  79         struct rb_root_cached free_space_bytes;
  80         u64 free_space;
  81         int extents_thresh;
  82         int free_extents;
  83         int total_bitmaps;
  84         int unit;
  85         u64 start;
  86         s32 discardable_extents[BTRFS_STAT_NR_ENTRIES];
  87         s64 discardable_bytes[BTRFS_STAT_NR_ENTRIES];
  88         const struct btrfs_free_space_op *op;
  89         struct btrfs_block_group *block_group;
  90         struct mutex cache_writeout_mutex;
  91         struct list_head trimming_ranges;
  92 };
  93
  94 struct btrfs_free_space_op {
  95         bool (*use_bitmap)(struct btrfs_free_space_ctl *ctl,
  96                            struct btrfs_free_space *info);
  97 };
  98
  99 struct btrfs_io_ctl {
 100         void *cur, *orig;
 101         struct page *page;
 102         struct page **pages;
 103         struct btrfs_fs_info *fs_info;
 104         struct inode *inode;
 105         unsigned long size;
 106         int index;
 107         int num_pages;
 108         int entries;
 109         int bitmaps;
 110 };
 111
 112 int __init btrfs_free_space_init(void);
 113 void __cold btrfs_free_space_exit(void);
 114 struct inode *lookup_free_space_inode(struct btrfs_block_group *block_group,
 115                 struct btrfs_path *path);
 116 int create_free_space_inode(struct btrfs_trans_handle *trans,
 117                             struct btrfs_block_group *block_group,
 118                             struct btrfs_path *path);
 119 int btrfs_remove_free_space_inode(struct btrfs_trans_handle *trans,
 120                                   struct inode *inode,
 121                                   struct btrfs_block_group *block_group);
 122
 123 int btrfs_truncate_free_space_cache(struct btrfs_trans_handle *trans,
 124                                     struct btrfs_block_group *block_group,
 125                                     struct inode *inode);
 126 int load_free_space_cache(struct btrfs_block_group *block_group);
 127 int btrfs_wait_cache_io(struct btrfs_trans_handle *trans,
 128                         struct btrfs_block_group *block_group,
 129                         struct btrfs_path *path);
 130 int btrfs_write_out_cache(struct btrfs_trans_handle *trans,
 131                           struct btrfs_block_group *block_group,
 132                           struct btrfs_path *path);
 133
 134 void btrfs_init_free_space_ctl(struct btrfs_block_group *block_group,
 135                                struct btrfs_free_space_ctl *ctl);
 136 int btrfs_add_free_space(struct btrfs_block_group *block_group,
 137                          u64 bytenr, u64 size);
 138 int btrfs_add_free_space_unused(struct btrfs_block_group *block_group,
 139                                 u64 bytenr, u64 size);
 140 int btrfs_add_free_space_async_trimmed(struct btrfs_block_group *block_group,
 141                                        u64 bytenr, u64 size);
 142 int btrfs_remove_free_space(struct btrfs_block_group *block_group,
 143                             u64 bytenr, u64 size);
 144 void btrfs_remove_free_space_cache(struct btrfs_block_group *block_group);
 145 bool btrfs_is_free_space_trimmed(struct btrfs_block_group *block_group);
 146 u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group,
 147                                u64 offset, u64 bytes, u64 empty_size,
 148                                u64 *max_extent_size);
 149 void btrfs_dump_free_space(struct btrfs_block_group *block_group,
 150                            u64 bytes);
 151 int btrfs_find_space_cluster(struct btrfs_block_group *block_group,
 152                              struct btrfs_free_cluster *cluster,
 153                              u64 offset, u64 bytes, u64 empty_size);
 154 void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster);
 155 u64 btrfs_alloc_from_cluster(struct btrfs_block_group *block_group,
 156                              struct btrfs_free_cluster *cluster, u64 bytes,
 157                              u64 min_start, u64 *max_extent_size);
 158 void btrfs_return_cluster_to_free_space(
 159                                struct btrfs_block_group *block_group,
 160                                struct btrfs_free_cluster *cluster);
 161 int btrfs_trim_block_group(struct btrfs_block_group *block_group,
 162                            u64 *trimmed, u64 start, u64 end, u64 minlen);
 163 int btrfs_trim_block_group_extents(struct btrfs_block_group *block_group,
 164                                    u64 *trimmed, u64 start, u64 end, u64 minlen,
 165                                    bool async);
 166 int btrfs_trim_block_group_bitmaps(struct btrfs_block_group *block_group,
 167                                    u64 *trimmed, u64 start, u64 end, u64 minlen,
 168                                    u64 maxlen, bool async);
 169
 170 bool btrfs_free_space_cache_v1_active(struct btrfs_fs_info *fs_info);
 171 int btrfs_set_free_space_cache_v1_active(struct btrfs_fs_info *fs_info, bool active);
 172 /* Support functions for running our sanity tests */
 173 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 174 int test_add_free_space_entry(struct btrfs_block_group *cache,
 175                               u64 offset, u64 bytes, bool bitmap);
 176 int test_check_exists(struct btrfs_block_group *cache, u64 offset, u64 bytes);
 177 #endif
 178
 179 #endif