libxfs/xfs_ag.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (c) 2018 Red Hat, Inc.
   4  * All rights reserved.
   5  */
   6
   7 #ifndef __LIBXFS_AG_H
   8 #define __LIBXFS_AG_H 1
   9
  10 struct xfs_mount;
  11 struct xfs_trans;
  12 struct xfs_perag;
  13
  14 /*
  15  * Per-ag infrastructure
  16  */
  17
  18 /* per-AG block reservation data structures*/
  19 struct xfs_ag_resv {
  20         /* number of blocks originally reserved here */
  21         xfs_extlen_t                    ar_orig_reserved;
  22         /* number of blocks reserved here */
  23         xfs_extlen_t                    ar_reserved;
  24         /* number of blocks originally asked for */
  25         xfs_extlen_t                    ar_asked;
  26 };
  27
  28 /*
  29  * Per-ag incore structure, copies of information in agf and agi, to improve the
  30  * performance of allocation group selection.
  31  */
  32 struct xfs_perag {
  33         struct xfs_mount *pag_mount;    /* owner filesystem */
  34         xfs_agnumber_t  pag_agno;       /* AG this structure belongs to */
  35         atomic_t        pag_ref;        /* passive reference count */
  36         atomic_t        pag_active_ref; /* active reference count */
  37         wait_queue_head_t pag_active_wq;/* woken active_ref falls to zero */
  38         char            pagf_init;      /* this agf's entry is initialized */
  39         char            pagi_init;      /* this agi's entry is initialized */
  40         char            pagf_metadata;  /* the agf is preferred to be metadata */
  41         char            pagi_inodeok;   /* The agi is ok for inodes */
  42         uint8_t         pagf_levels[XFS_BTNUM_AGF];
  43                                         /* # of levels in bno & cnt btree */
  44         bool            pagf_agflreset; /* agfl requires reset before use */
  45         uint32_t        pagf_flcount;   /* count of blocks in freelist */
  46         xfs_extlen_t    pagf_freeblks;  /* total free blocks */
  47         xfs_extlen_t    pagf_longest;   /* longest free space */
  48         uint32_t        pagf_btreeblks; /* # of blocks held in AGF btrees */
  49         xfs_agino_t     pagi_freecount; /* number of free inodes */
  50         xfs_agino_t     pagi_count;     /* number of allocated inodes */
  51
  52         /*
  53          * Inode allocation search lookup optimisation.
  54          * If the pagino matches, the search for new inodes
  55          * doesn't need to search the near ones again straight away
  56          */
  57         xfs_agino_t     pagl_pagino;
  58         xfs_agino_t     pagl_leftrec;
  59         xfs_agino_t     pagl_rightrec;
  60
  61         int             pagb_count;     /* pagb slots in use */
  62         uint8_t         pagf_refcount_level; /* recount btree height */
  63
  64         /* Blocks reserved for all kinds of metadata. */
  65         struct xfs_ag_resv      pag_meta_resv;
  66         /* Blocks reserved for the reverse mapping btree. */
  67         struct xfs_ag_resv      pag_rmapbt_resv;
  68
  69         /* for rcu-safe freeing */
  70         struct rcu_head rcu_head;
  71
  72         /* Precalculated geometry info */
  73         xfs_agblock_t           block_count;
  74         xfs_agblock_t           min_block;
  75         xfs_agino_t             agino_min;
  76         xfs_agino_t             agino_max;
  77
  78 #ifdef __KERNEL__
  79         /* -- kernel only structures below this line -- */
  80
  81         /*
  82          * Bitsets of per-ag metadata that have been checked and/or are sick.
  83          * Callers should hold pag_state_lock before accessing this field.
  84          */
  85         uint16_t        pag_checked;
  86         uint16_t        pag_sick;
  87         spinlock_t      pag_state_lock;
  88
  89         spinlock_t      pagb_lock;      /* lock for pagb_tree */
  90         struct rb_root  pagb_tree;      /* ordered tree of busy extents */
  91         unsigned int    pagb_gen;       /* generation count for pagb_tree */
  92         wait_queue_head_t pagb_wait;    /* woken when pagb_gen changes */
  93
  94         atomic_t        pagf_fstrms;    /* # of filestreams active in this AG */
  95
  96         spinlock_t      pag_ici_lock;   /* incore inode cache lock */
  97         struct radix_tree_root pag_ici_root;    /* incore inode cache root */
  98         int             pag_ici_reclaimable;    /* reclaimable inodes */
  99         unsigned long   pag_ici_reclaim_cursor; /* reclaim restart point */
 100
 101         /* buffer cache index */
 102         spinlock_t      pag_buf_lock;   /* lock for pag_buf_hash */
 103         struct rhashtable pag_buf_hash;
 104
 105         /* background prealloc block trimming */
 106         struct delayed_work     pag_blockgc_work;
 107
 108 #endif /* __KERNEL__ */
 109 };
 110
 111 int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
 112                         xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi);
 113 int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
 114 void xfs_free_perag(struct xfs_mount *mp);
 115
 116 /* Passive AG references */
 117 struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
 118 struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
 119                 unsigned int tag);
 120 void xfs_perag_put(struct xfs_perag *pag);
 121
 122 /* Active AG references */
 123 struct xfs_perag *xfs_perag_grab(struct xfs_mount *, xfs_agnumber_t);
 124 struct xfs_perag *xfs_perag_grab_tag(struct xfs_mount *, xfs_agnumber_t,
 125                                    int tag);
 126 void xfs_perag_rele(struct xfs_perag *pag);
 127
 128 /*
 129  * Per-ag geometry infomation and validation
 130  */
 131 xfs_agblock_t xfs_ag_block_count(struct xfs_mount *mp, xfs_agnumber_t agno);
 132 void xfs_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
 133                 xfs_agino_t *first, xfs_agino_t *last);
 134
 135 static inline bool
 136 xfs_verify_agbno(struct xfs_perag *pag, xfs_agblock_t agbno)
 137 {
 138         if (agbno >= pag->block_count)
 139                 return false;
 140         if (agbno <= pag->min_block)
 141                 return false;
 142         return true;
 143 }
 144
 145 static inline bool
 146 xfs_verify_agbext(
 147         struct xfs_perag        *pag,
 148         xfs_agblock_t           agbno,
 149         xfs_agblock_t           len)
 150 {
 151         if (agbno + len <= agbno)
 152                 return false;
 153
 154         if (!xfs_verify_agbno(pag, agbno))
 155                 return false;
 156
 157         return xfs_verify_agbno(pag, agbno + len - 1);
 158 }
 159
 160 /*
 161  * Verify that an AG inode number pointer neither points outside the AG
 162  * nor points at static metadata.
 163  */
 164 static inline bool
 165 xfs_verify_agino(struct xfs_perag *pag, xfs_agino_t agino)
 166 {
 167         if (agino < pag->agino_min)
 168                 return false;
 169         if (agino > pag->agino_max)
 170                 return false;
 171         return true;
 172 }
 173
 174 /*
 175  * Verify that an AG inode number pointer neither points outside the AG
 176  * nor points at static metadata, or is NULLAGINO.
 177  */
 178 static inline bool
 179 xfs_verify_agino_or_null(struct xfs_perag *pag, xfs_agino_t agino)
 180 {
 181         if (agino == NULLAGINO)
 182                 return true;
 183         return xfs_verify_agino(pag, agino);
 184 }
 185
 186 static inline bool
 187 xfs_ag_contains_log(struct xfs_mount *mp, xfs_agnumber_t agno)
 188 {
 189         return mp->m_sb.sb_logstart > 0 &&
 190                agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
 191 }
 192
 193 /*
 194  * Perag iteration APIs
 195  */
 196 static inline struct xfs_perag *
 197 xfs_perag_next(
 198         struct xfs_perag        *pag,
 199         xfs_agnumber_t          *agno,
 200         xfs_agnumber_t          end_agno)
 201 {
 202         struct xfs_mount        *mp = pag->pag_mount;
 203
 204         *agno = pag->pag_agno + 1;
 205         xfs_perag_rele(pag);
 206         while (*agno <= end_agno) {
 207                 pag = xfs_perag_grab(mp, *agno);
 208                 if (pag)
 209                         return pag;
 210                 (*agno)++;
 211         }
 212         return NULL;
 213 }
 214
 215 #define for_each_perag_range(mp, agno, end_agno, pag) \
 216         for ((pag) = xfs_perag_grab((mp), (agno)); \
 217                 (pag) != NULL; \
 218                 (pag) = xfs_perag_next((pag), &(agno), (end_agno)))
 219
 220 #define for_each_perag_from(mp, agno, pag) \
 221         for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
 222
 223
 224 #define for_each_perag(mp, agno, pag) \
 225         (agno) = 0; \
 226         for_each_perag_from((mp), (agno), (pag))
 227
 228 #define for_each_perag_tag(mp, agno, pag, tag) \
 229         for ((agno) = 0, (pag) = xfs_perag_grab_tag((mp), 0, (tag)); \
 230                 (pag) != NULL; \
 231                 (agno) = (pag)->pag_agno + 1, \
 232                 xfs_perag_rele(pag), \
 233                 (pag) = xfs_perag_grab_tag((mp), (agno), (tag)))
 234
 235 struct aghdr_init_data {
 236         /* per ag data */
 237         xfs_agblock_t           agno;           /* ag to init */
 238         xfs_extlen_t            agsize;         /* new AG size */
 239         struct list_head        buffer_list;    /* buffer writeback list */
 240         xfs_rfsblock_t          nfree;          /* cumulative new free space */
 241
 242         /* per header data */
 243         xfs_daddr_t             daddr;          /* header location */
 244         size_t                  numblks;        /* size of header */
 245         xfs_btnum_t             type;           /* type of btree root block */
 246 };
 247
 248 int xfs_ag_init_headers(struct xfs_mount *mp, struct aghdr_init_data *id);
 249 int xfs_ag_shrink_space(struct xfs_perag *pag, struct xfs_trans **tpp,
 250                         xfs_extlen_t delta);
 251 int xfs_ag_extend_space(struct xfs_perag *pag, struct xfs_trans *tp,
 252                         xfs_extlen_t len);
 253 int xfs_ag_get_geometry(struct xfs_perag *pag, struct xfs_ag_geometry *ageo);
 254
 255 #endif /* __LIBXFS_AG_H */