fs/xfs/libxfs/xfs_alloc.h

   1 /*
   2  * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #ifndef __XFS_ALLOC_H__
  19 #define __XFS_ALLOC_H__
  20
  21 struct xfs_buf;
  22 struct xfs_btree_cur;
  23 struct xfs_mount;
  24 struct xfs_perag;
  25 struct xfs_trans;
  26
  27 extern struct workqueue_struct *xfs_alloc_wq;
  28
  29 /*
  30  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
  31  */
  32 #define XFS_ALLOCTYPE_ANY_AG    0x01    /* allocate anywhere, use rotor */
  33 #define XFS_ALLOCTYPE_FIRST_AG  0x02    /* ... start at ag 0 */
  34 #define XFS_ALLOCTYPE_START_AG  0x04    /* anywhere, start in this a.g. */
  35 #define XFS_ALLOCTYPE_THIS_AG   0x08    /* anywhere in this a.g. */
  36 #define XFS_ALLOCTYPE_START_BNO 0x10    /* near this block else anywhere */
  37 #define XFS_ALLOCTYPE_NEAR_BNO  0x20    /* in this a.g. and near this block */
  38 #define XFS_ALLOCTYPE_THIS_BNO  0x40    /* at exactly this block */
  39
  40 /* this should become an enum again when the tracing code is fixed */
  41 typedef unsigned int xfs_alloctype_t;
  42
  43 #define XFS_ALLOC_TYPES \
  44         { XFS_ALLOCTYPE_ANY_AG,         "ANY_AG" }, \
  45         { XFS_ALLOCTYPE_FIRST_AG,       "FIRST_AG" }, \
  46         { XFS_ALLOCTYPE_START_AG,       "START_AG" }, \
  47         { XFS_ALLOCTYPE_THIS_AG,        "THIS_AG" }, \
  48         { XFS_ALLOCTYPE_START_BNO,      "START_BNO" }, \
  49         { XFS_ALLOCTYPE_NEAR_BNO,       "NEAR_BNO" }, \
  50         { XFS_ALLOCTYPE_THIS_BNO,       "THIS_BNO" }
  51
  52 /*
  53  * Flags for xfs_alloc_fix_freelist.
  54  */
  55 #define XFS_ALLOC_FLAG_TRYLOCK  0x00000001  /* use trylock for buffer locking */
  56 #define XFS_ALLOC_FLAG_FREEING  0x00000002  /* indicate caller is freeing extents*/
  57 #define XFS_ALLOC_FLAG_NORMAP   0x00000004  /* don't modify the rmapbt */
  58 #define XFS_ALLOC_FLAG_NOSHRINK 0x00000008  /* don't shrink the freelist */
  59
  60
  61 /*
  62  * Argument structure for xfs_alloc routines.
  63  * This is turned into a structure to avoid having 20 arguments passed
  64  * down several levels of the stack.
  65  */
  66 typedef struct xfs_alloc_arg {
  67         struct xfs_trans *tp;           /* transaction pointer */
  68         struct xfs_mount *mp;           /* file system mount point */
  69         struct xfs_buf  *agbp;          /* buffer for a.g. freelist header */
  70         struct xfs_perag *pag;          /* per-ag struct for this agno */
  71         struct xfs_inode *ip;           /* for userdata zeroing method */
  72         xfs_fsblock_t   fsbno;          /* file system block number */
  73         xfs_agnumber_t  agno;           /* allocation group number */
  74         xfs_agblock_t   agbno;          /* allocation group-relative block # */
  75         xfs_extlen_t    minlen;         /* minimum size of extent */
  76         xfs_extlen_t    maxlen;         /* maximum size of extent */
  77         xfs_extlen_t    mod;            /* mod value for extent size */
  78         xfs_extlen_t    prod;           /* prod value for extent size */
  79         xfs_extlen_t    minleft;        /* min blocks must be left after us */
  80         xfs_extlen_t    total;          /* total blocks needed in xaction */
  81         xfs_extlen_t    alignment;      /* align answer to multiple of this */
  82         xfs_extlen_t    minalignslop;   /* slop for minlen+alignment calcs */
  83         xfs_agblock_t   min_agbno;      /* set an agbno range for NEAR allocs */
  84         xfs_agblock_t   max_agbno;      /* ... */
  85         xfs_extlen_t    len;            /* output: actual size of extent */
  86         xfs_alloctype_t type;           /* allocation type XFS_ALLOCTYPE_... */
  87         xfs_alloctype_t otype;          /* original allocation type */
  88         char            wasdel;         /* set if allocation was prev delayed */
  89         char            wasfromfl;      /* set if allocation is from freelist */
  90         char            isfl;           /* set if is freelist blocks - !acctg */
  91         char            userdata;       /* mask defining userdata treatment */
  92         xfs_fsblock_t   firstblock;     /* io first block allocated */
  93         struct xfs_owner_info   oinfo;  /* owner of blocks being allocated */
  94 } xfs_alloc_arg_t;
  95
  96 /*
  97  * Defines for userdata
  98  */
  99 #define XFS_ALLOC_USERDATA              (1 << 0)/* allocation is for user data*/
 100 #define XFS_ALLOC_INITIAL_USER_DATA     (1 << 1)/* special case start of file */
 101 #define XFS_ALLOC_USERDATA_ZERO         (1 << 2)/* zero extent on allocation */
 102
 103 /* freespace limit calculations */
 104 #define XFS_ALLOC_AGFL_RESERVE  4
 105 unsigned int xfs_alloc_set_aside(struct xfs_mount *mp);
 106 unsigned int xfs_alloc_ag_max_usable(struct xfs_mount *mp);
 107
 108 xfs_extlen_t xfs_alloc_longest_free_extent(struct xfs_mount *mp,
 109                 struct xfs_perag *pag, xfs_extlen_t need);
 110 unsigned int xfs_alloc_min_freelist(struct xfs_mount *mp,
 111                 struct xfs_perag *pag);
 112
 113 /*
 114  * Compute and fill in value of m_ag_maxlevels.
 115  */
 116 void
 117 xfs_alloc_compute_maxlevels(
 118         struct xfs_mount        *mp);   /* file system mount structure */
 119
 120 /*
 121  * Get a block from the freelist.
 122  * Returns with the buffer for the block gotten.
 123  */
 124 int                             /* error */
 125 xfs_alloc_get_freelist(
 126         struct xfs_trans *tp,   /* transaction pointer */
 127         struct xfs_buf  *agbp,  /* buffer containing the agf structure */
 128         xfs_agblock_t   *bnop,  /* block address retrieved from freelist */
 129         int             btreeblk); /* destination is a AGF btree */
 130
 131 /*
 132  * Log the given fields from the agf structure.
 133  */
 134 void
 135 xfs_alloc_log_agf(
 136         struct xfs_trans *tp,   /* transaction pointer */
 137         struct xfs_buf  *bp,    /* buffer for a.g. freelist header */
 138         int             fields);/* mask of fields to be logged (XFS_AGF_...) */
 139
 140 /*
 141  * Interface for inode allocation to force the pag data to be initialized.
 142  */
 143 int                             /* error */
 144 xfs_alloc_pagf_init(
 145         struct xfs_mount *mp,   /* file system mount structure */
 146         struct xfs_trans *tp,   /* transaction pointer */
 147         xfs_agnumber_t  agno,   /* allocation group number */
 148         int             flags); /* XFS_ALLOC_FLAGS_... */
 149
 150 /*
 151  * Put the block on the freelist for the allocation group.
 152  */
 153 int                             /* error */
 154 xfs_alloc_put_freelist(
 155         struct xfs_trans *tp,   /* transaction pointer */
 156         struct xfs_buf  *agbp,  /* buffer for a.g. freelist header */
 157         struct xfs_buf  *agflbp,/* buffer for a.g. free block array */
 158         xfs_agblock_t   bno,    /* block being freed */
 159         int             btreeblk); /* owner was a AGF btree */
 160
 161 /*
 162  * Read in the allocation group header (free/alloc section).
 163  */
 164 int                                     /* error  */
 165 xfs_alloc_read_agf(
 166         struct xfs_mount *mp,           /* mount point structure */
 167         struct xfs_trans *tp,           /* transaction pointer */
 168         xfs_agnumber_t  agno,           /* allocation group number */
 169         int             flags,          /* XFS_ALLOC_FLAG_... */
 170         struct xfs_buf  **bpp);         /* buffer for the ag freelist header */
 171
 172 /*
 173  * Allocate an extent (variable-size).
 174  */
 175 int                             /* error */
 176 xfs_alloc_vextent(
 177         xfs_alloc_arg_t *args); /* allocation argument structure */
 178
 179 /*
 180  * Free an extent.
 181  */
 182 int                             /* error */
 183 xfs_free_extent(
 184         struct xfs_trans        *tp,    /* transaction pointer */
 185         xfs_fsblock_t           bno,    /* starting block number of extent */
 186         xfs_extlen_t            len,    /* length of extent */
 187         struct xfs_owner_info   *oinfo);/* extent owner */
 188
 189 int                             /* error */
 190 xfs_alloc_lookup_ge(
 191         struct xfs_btree_cur    *cur,   /* btree cursor */
 192         xfs_agblock_t           bno,    /* starting block of extent */
 193         xfs_extlen_t            len,    /* length of extent */
 194         int                     *stat); /* success/failure */
 195
 196 int                                     /* error */
 197 xfs_alloc_get_rec(
 198         struct xfs_btree_cur    *cur,   /* btree cursor */
 199         xfs_agblock_t           *bno,   /* output: starting block of extent */
 200         xfs_extlen_t            *len,   /* output: length of extent */
 201         int                     *stat); /* output: success/failure */
 202
 203 int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,
 204                         xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);
 205 int xfs_alloc_fix_freelist(struct xfs_alloc_arg *args, int flags);
 206 int xfs_free_extent_fix_freelist(struct xfs_trans *tp, xfs_agnumber_t agno,
 207                 struct xfs_buf **agbp);
 208
 209 xfs_extlen_t xfs_prealloc_blocks(struct xfs_mount *mp);
 210
 211 #endif  /* __XFS_ALLOC_H__ */