fs/xfs/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_mount;
  23 struct xfs_perag;
  24 struct xfs_trans;
  25
  26 /*
  27  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
  28  */
  29 typedef enum xfs_alloctype
  30 {
  31         XFS_ALLOCTYPE_ANY_AG,           /* allocate anywhere, use rotor */
  32         XFS_ALLOCTYPE_FIRST_AG,         /* ... start at ag 0 */
  33         XFS_ALLOCTYPE_START_AG,         /* anywhere, start in this a.g. */
  34         XFS_ALLOCTYPE_THIS_AG,          /* anywhere in this a.g. */
  35         XFS_ALLOCTYPE_START_BNO,        /* near this block else anywhere */
  36         XFS_ALLOCTYPE_NEAR_BNO,         /* in this a.g. and near this block */
  37         XFS_ALLOCTYPE_THIS_BNO          /* at exactly this block */
  38 } xfs_alloctype_t;
  39
  40 /*
  41  * Flags for xfs_alloc_fix_freelist.
  42  */
  43 #define XFS_ALLOC_FLAG_TRYLOCK  0x00000001  /* use trylock for buffer locking */
  44
  45 /*
  46  * Argument structure for xfs_alloc routines.
  47  * This is turned into a structure to avoid having 20 arguments passed
  48  * down several levels of the stack.
  49  */
  50 typedef struct xfs_alloc_arg {
  51         struct xfs_trans *tp;           /* transaction pointer */
  52         struct xfs_mount *mp;           /* file system mount point */
  53         struct xfs_buf  *agbp;          /* buffer for a.g. freelist header */
  54         struct xfs_perag *pag;          /* per-ag struct for this agno */
  55         xfs_fsblock_t   fsbno;          /* file system block number */
  56         xfs_agnumber_t  agno;           /* allocation group number */
  57         xfs_agblock_t   agbno;          /* allocation group-relative block # */
  58         xfs_extlen_t    minlen;         /* minimum size of extent */
  59         xfs_extlen_t    maxlen;         /* maximum size of extent */
  60         xfs_extlen_t    mod;            /* mod value for extent size */
  61         xfs_extlen_t    prod;           /* prod value for extent size */
  62         xfs_extlen_t    minleft;        /* min blocks must be left after us */
  63         xfs_extlen_t    total;          /* total blocks needed in xaction */
  64         xfs_extlen_t    alignment;      /* align answer to multiple of this */
  65         xfs_extlen_t    minalignslop;   /* slop for minlen+alignment calcs */
  66         xfs_extlen_t    len;            /* output: actual size of extent */
  67         xfs_alloctype_t type;           /* allocation type XFS_ALLOCTYPE_... */
  68         xfs_alloctype_t otype;          /* original allocation type */
  69         char            wasdel;         /* set if allocation was prev delayed */
  70         char            wasfromfl;      /* set if allocation is from freelist */
  71         char            isfl;           /* set if is freelist blocks - !acctg */
  72         char            userdata;       /* set if this is user data */
  73 } xfs_alloc_arg_t;
  74
  75 /*
  76  * Defines for userdata
  77  */
  78 #define XFS_ALLOC_USERDATA              1       /* allocation is for user data*/
  79 #define XFS_ALLOC_INITIAL_USER_DATA     2       /* special case start of file */
  80
  81
  82 #ifdef __KERNEL__
  83
  84 #if defined(XFS_ALLOC_TRACE)
  85 /*
  86  * Allocation tracing buffer size.
  87  */
  88 #define XFS_ALLOC_TRACE_SIZE    4096
  89 extern ktrace_t *xfs_alloc_trace_buf;
  90
  91 /*
  92  * Types for alloc tracing.
  93  */
  94 #define XFS_ALLOC_KTRACE_ALLOC  1
  95 #define XFS_ALLOC_KTRACE_FREE   2
  96 #define XFS_ALLOC_KTRACE_MODAGF 3
  97 #define XFS_ALLOC_KTRACE_BUSY   4
  98 #define XFS_ALLOC_KTRACE_UNBUSY 5
  99 #define XFS_ALLOC_KTRACE_BUSYSEARCH     6
 100 #endif
 101
 102 /*
 103  * Compute and fill in value of m_ag_maxlevels.
 104  */
 105 void
 106 xfs_alloc_compute_maxlevels(
 107         struct xfs_mount        *mp);   /* file system mount structure */
 108
 109 /*
 110  * Get a block from the freelist.
 111  * Returns with the buffer for the block gotten.
 112  */
 113 int                             /* error */
 114 xfs_alloc_get_freelist(
 115         struct xfs_trans *tp,   /* transaction pointer */
 116         struct xfs_buf  *agbp,  /* buffer containing the agf structure */
 117         xfs_agblock_t   *bnop); /* block address retrieved from freelist */
 118
 119 /*
 120  * Log the given fields from the agf structure.
 121  */
 122 void
 123 xfs_alloc_log_agf(
 124         struct xfs_trans *tp,   /* transaction pointer */
 125         struct xfs_buf  *bp,    /* buffer for a.g. freelist header */
 126         int             fields);/* mask of fields to be logged (XFS_AGF_...) */
 127
 128 /*
 129  * Interface for inode allocation to force the pag data to be initialized.
 130  */
 131 int                             /* error */
 132 xfs_alloc_pagf_init(
 133         struct xfs_mount *mp,   /* file system mount structure */
 134         struct xfs_trans *tp,   /* transaction pointer */
 135         xfs_agnumber_t  agno,   /* allocation group number */
 136         int             flags); /* XFS_ALLOC_FLAGS_... */
 137
 138 /*
 139  * Put the block on the freelist for the allocation group.
 140  */
 141 int                             /* error */
 142 xfs_alloc_put_freelist(
 143         struct xfs_trans *tp,   /* transaction pointer */
 144         struct xfs_buf  *agbp,  /* buffer for a.g. freelist header */
 145         struct xfs_buf  *agflbp,/* buffer for a.g. free block array */
 146         xfs_agblock_t   bno);   /* block being freed */
 147
 148 /*
 149  * Read in the allocation group header (free/alloc section).
 150  */
 151 int                                     /* error  */
 152 xfs_alloc_read_agf(
 153         struct xfs_mount *mp,           /* mount point structure */
 154         struct xfs_trans *tp,           /* transaction pointer */
 155         xfs_agnumber_t  agno,           /* allocation group number */
 156         int             flags,          /* XFS_ALLOC_FLAG_... */
 157         struct xfs_buf  **bpp);         /* buffer for the ag freelist header */
 158
 159 /*
 160  * Allocate an extent (variable-size).
 161  */
 162 int                             /* error */
 163 xfs_alloc_vextent(
 164         xfs_alloc_arg_t *args); /* allocation argument structure */
 165
 166 /*
 167  * Free an extent.
 168  */
 169 int                             /* error */
 170 xfs_free_extent(
 171         struct xfs_trans *tp,   /* transaction pointer */
 172         xfs_fsblock_t   bno,    /* starting block number of extent */
 173         xfs_extlen_t    len);   /* length of extent */
 174
 175 void
 176 xfs_alloc_mark_busy(xfs_trans_t *tp,
 177                 xfs_agnumber_t agno,
 178                 xfs_agblock_t bno,
 179                 xfs_extlen_t len);
 180
 181 void
 182 xfs_alloc_clear_busy(xfs_trans_t *tp,
 183                 xfs_agnumber_t ag,
 184                 int idx);
 185
 186
 187 #endif  /* __KERNEL__ */
 188
 189 #endif  /* __XFS_ALLOC_H__ */