fs/xfs/xfs_alloc.h

   1 /*
   2  * Copyright (c) 2000-2002 Silicon Graphics, Inc.  All Rights Reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it would be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11  *
  12  * Further, this software is distributed without any warranty that it is
  13  * free of the rightful claim of any third person regarding infringement
  14  * or the like.  Any license provided herein, whether implied or
  15  * otherwise, applies only to this software file.  Patent licenses, if
  16  * any, provided herein do not apply to combinations of this program with
  17  * other software, or any other product whatsoever.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write the Free Software Foundation, Inc., 59
  21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24  * Mountain View, CA  94043, or:
  25  *
  26  * http://www.sgi.com
  27  *
  28  * For further information regarding this notice, see:
  29  *
  30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31  */
  32 #ifndef __XFS_ALLOC_H__
  33 #define __XFS_ALLOC_H__
  34
  35 struct xfs_buf;
  36 struct xfs_mount;
  37 struct xfs_perag;
  38 struct xfs_trans;
  39
  40 /*
  41  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
  42  */
  43 typedef enum xfs_alloctype
  44 {
  45         XFS_ALLOCTYPE_ANY_AG,           /* allocate anywhere, use rotor */
  46         XFS_ALLOCTYPE_FIRST_AG,         /* ... start at ag 0 */
  47         XFS_ALLOCTYPE_START_AG,         /* anywhere, start in this a.g. */
  48         XFS_ALLOCTYPE_THIS_AG,          /* anywhere in this a.g. */
  49         XFS_ALLOCTYPE_START_BNO,        /* near this block else anywhere */
  50         XFS_ALLOCTYPE_NEAR_BNO,         /* in this a.g. and near this block */
  51         XFS_ALLOCTYPE_THIS_BNO          /* at exactly this block */
  52 } xfs_alloctype_t;
  53
  54 /*
  55  * Flags for xfs_alloc_fix_freelist.
  56  */
  57 #define XFS_ALLOC_FLAG_TRYLOCK  0x00000001  /* use trylock for buffer locking */
  58
  59 /*
  60  * Argument structure for xfs_alloc routines.
  61  * This is turned into a structure to avoid having 20 arguments passed
  62  * down several levels of the stack.
  63  */
  64 typedef struct xfs_alloc_arg {
  65         struct xfs_trans *tp;           /* transaction pointer */
  66         struct xfs_mount *mp;           /* file system mount point */
  67         struct xfs_buf  *agbp;          /* buffer for a.g. freelist header */
  68         struct xfs_perag *pag;          /* per-ag struct for this agno */
  69         xfs_fsblock_t   fsbno;          /* file system block number */
  70         xfs_agnumber_t  agno;           /* allocation group number */
  71         xfs_agblock_t   agbno;          /* allocation group-relative block # */
  72         xfs_extlen_t    minlen;         /* minimum size of extent */
  73         xfs_extlen_t    maxlen;         /* maximum size of extent */
  74         xfs_extlen_t    mod;            /* mod value for extent size */
  75         xfs_extlen_t    prod;           /* prod value for extent size */
  76         xfs_extlen_t    minleft;        /* min blocks must be left after us */
  77         xfs_extlen_t    total;          /* total blocks needed in xaction */
  78         xfs_extlen_t    alignment;      /* align answer to multiple of this */
  79         xfs_extlen_t    minalignslop;   /* slop for minlen+alignment calcs */
  80         xfs_extlen_t    len;            /* output: actual size of extent */
  81         xfs_alloctype_t type;           /* allocation type XFS_ALLOCTYPE_... */
  82         xfs_alloctype_t otype;          /* original allocation type */
  83         char            wasdel;         /* set if allocation was prev delayed */
  84         char            wasfromfl;      /* set if allocation is from freelist */
  85         char            isfl;           /* set if is freelist blocks - !actg */
  86         char            userdata;       /* set if this is user data */
  87 } xfs_alloc_arg_t;
  88
  89 /*
  90  * Defines for userdata
  91  */
  92 #define XFS_ALLOC_USERDATA              1       /* allocation is for user data*/
  93 #define XFS_ALLOC_INITIAL_USER_DATA     2       /* special case start of file */
  94
  95
  96 #ifdef __KERNEL__
  97
  98 #if defined(XFS_ALLOC_TRACE)
  99 /*
 100  * Allocation tracing buffer size.
 101  */
 102 #define XFS_ALLOC_TRACE_SIZE    4096
 103 extern ktrace_t *xfs_alloc_trace_buf;
 104
 105 /*
 106  * Types for alloc tracing.
 107  */
 108 #define XFS_ALLOC_KTRACE_ALLOC  1
 109 #define XFS_ALLOC_KTRACE_FREE   2
 110 #define XFS_ALLOC_KTRACE_MODAGF 3
 111 #define XFS_ALLOC_KTRACE_BUSY   4
 112 #define XFS_ALLOC_KTRACE_UNBUSY 5
 113 #define XFS_ALLOC_KTRACE_BUSYSEARCH     6
 114 #endif
 115
 116 /*
 117  * Compute and fill in value of m_ag_maxlevels.
 118  */
 119 void
 120 xfs_alloc_compute_maxlevels(
 121         struct xfs_mount        *mp);   /* file system mount structure */
 122
 123 /*
 124  * Get a block from the freelist.
 125  * Returns with the buffer for the block gotten.
 126  */
 127 int                             /* error */
 128 xfs_alloc_get_freelist(
 129         struct xfs_trans *tp,   /* transaction pointer */
 130         struct xfs_buf  *agbp,  /* buffer containing the agf structure */
 131         xfs_agblock_t   *bnop); /* block address retrieved from freelist */
 132
 133 /*
 134  * Log the given fields from the agf structure.
 135  */
 136 void
 137 xfs_alloc_log_agf(
 138         struct xfs_trans *tp,   /* transaction pointer */
 139         struct xfs_buf  *bp,    /* buffer for a.g. freelist header */
 140         int             fields);/* mask of fields to be logged (XFS_AGF_...) */
 141
 142 /*
 143  * Interface for inode allocation to force the pag data to be initialized.
 144  */
 145 int                             /* error */
 146 xfs_alloc_pagf_init(
 147         struct xfs_mount *mp,   /* file system mount structure */
 148         struct xfs_trans *tp,   /* transaction pointer */
 149         xfs_agnumber_t  agno,   /* allocation group number */
 150         int             flags); /* XFS_ALLOC_FLAGS_... */
 151
 152 /*
 153  * Put the block on the freelist for the allocation group.
 154  */
 155 int                             /* error */
 156 xfs_alloc_put_freelist(
 157         struct xfs_trans *tp,   /* transaction pointer */
 158         struct xfs_buf  *agbp,  /* buffer for a.g. freelist header */
 159         struct xfs_buf  *agflbp,/* buffer for a.g. free block array */
 160         xfs_agblock_t   bno);   /* block being freed */
 161
 162 /*
 163  * Read in the allocation group header (free/alloc section).
 164  */
 165 int                                     /* error  */
 166 xfs_alloc_read_agf(
 167         struct xfs_mount *mp,           /* mount point structure */
 168         struct xfs_trans *tp,           /* transaction pointer */
 169         xfs_agnumber_t  agno,           /* allocation group number */
 170         int             flags,          /* XFS_ALLOC_FLAG_... */
 171         struct xfs_buf  **bpp);         /* buffer for the ag freelist header */
 172
 173 /*
 174  * Allocate an extent (variable-size).
 175  */
 176 int                             /* error */
 177 xfs_alloc_vextent(
 178         xfs_alloc_arg_t *args); /* allocation argument structure */
 179
 180 /*
 181  * Free an extent.
 182  */
 183 int                             /* error */
 184 xfs_free_extent(
 185         struct xfs_trans *tp,   /* transaction pointer */
 186         xfs_fsblock_t   bno,    /* starting block number of extent */
 187         xfs_extlen_t    len);   /* length of extent */
 188
 189 void
 190 xfs_alloc_mark_busy(xfs_trans_t *tp,
 191                 xfs_agnumber_t agno,
 192                 xfs_agblock_t bno,
 193                 xfs_extlen_t len);
 194
 195 void
 196 xfs_alloc_clear_busy(xfs_trans_t *tp,
 197                 xfs_agnumber_t ag,
 198                 int idx);
 199
 200
 201 #endif  /* __KERNEL__ */
 202
 203 #endif  /* __XFS_ALLOC_H__ */