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 21struct xfs_buf; 22struct xfs_mount; 23struct xfs_perag; 24struct xfs_trans; 25 26/* 27 * Freespace allocation types. Argument to xfs_alloc_[v]extent. 28 */ 29typedef 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#define XFS_ALLOC_FLAG_FREEING 0x00000002 /* indicate caller is freeing extents*/ 45 46/* 47 * In order to avoid ENOSPC-related deadlock caused by 48 * out-of-order locking of AGF buffer (PV 947395), we place 49 * constraints on the relationship among actual allocations for 50 * data blocks, freelist blocks, and potential file data bmap 51 * btree blocks. However, these restrictions may result in no 52 * actual space allocated for a delayed extent, for example, a data 53 * block in a certain AG is allocated but there is no additional 54 * block for the additional bmap btree block due to a split of the 55 * bmap btree of the file. The result of this may lead to an 56 * infinite loop in xfssyncd when the file gets flushed to disk and 57 * all delayed extents need to be actually allocated. To get around 58 * this, we explicitly set aside a few blocks which will not be 59 * reserved in delayed allocation. Considering the minimum number of 60 * needed freelist blocks is 4 fsbs _per AG_, a potential split of file's bmap 61 * btree requires 1 fsb, so we set the number of set-aside blocks 62 * to 4 + 4*agcount. 63 */ 64#define XFS_ALLOC_SET_ASIDE(mp) (4 + ((mp)->m_sb.sb_agcount * 4)) 65 66/* 67 * Argument structure for xfs_alloc routines. 68 * This is turned into a structure to avoid having 20 arguments passed 69 * down several levels of the stack. 70 */ 71typedef struct xfs_alloc_arg { 72 struct xfs_trans *tp; /* transaction pointer */ 73 struct xfs_mount *mp; /* file system mount point */ 74 struct xfs_buf *agbp; /* buffer for a.g. freelist header */ 75 struct xfs_perag *pag; /* per-ag struct for this agno */ 76 xfs_fsblock_t fsbno; /* file system block number */ 77 xfs_agnumber_t agno; /* allocation group number */ 78 xfs_agblock_t agbno; /* allocation group-relative block # */ 79 xfs_extlen_t minlen; /* minimum size of extent */ 80 xfs_extlen_t maxlen; /* maximum size of extent */ 81 xfs_extlen_t mod; /* mod value for extent size */ 82 xfs_extlen_t prod; /* prod value for extent size */ 83 xfs_extlen_t minleft; /* min blocks must be left after us */ 84 xfs_extlen_t total; /* total blocks needed in xaction */ 85 xfs_extlen_t alignment; /* align answer to multiple of this */ 86 xfs_extlen_t minalignslop; /* slop for minlen+alignment calcs */ 87 xfs_extlen_t len; /* output: actual size of extent */ 88 xfs_alloctype_t type; /* allocation type XFS_ALLOCTYPE_... */ 89 xfs_alloctype_t otype; /* original allocation type */ 90 char wasdel; /* set if allocation was prev delayed */ 91 char wasfromfl; /* set if allocation is from freelist */ 92 char isfl; /* set if is freelist blocks - !acctg */ 93 char userdata; /* set if this is user data */ 94 xfs_fsblock_t firstblock; /* io first block allocated */ 95} xfs_alloc_arg_t; 96 97/* 98 * Defines for userdata 99 */ 100#define XFS_ALLOC_USERDATA 1 /* allocation is for user data*/ 101#define XFS_ALLOC_INITIAL_USER_DATA 2 /* special case start of file */ 102 103 104#ifdef __KERNEL__ 105 106#if defined(XFS_ALLOC_TRACE) 107/* 108 * Allocation tracing buffer size. 109 */ 110#define XFS_ALLOC_TRACE_SIZE 4096 111extern ktrace_t *xfs_alloc_trace_buf; 112 113/* 114 * Types for alloc tracing. 115 */ 116#define XFS_ALLOC_KTRACE_ALLOC 1 117#define XFS_ALLOC_KTRACE_FREE 2 118#define XFS_ALLOC_KTRACE_MODAGF 3 119#define XFS_ALLOC_KTRACE_BUSY 4 120#define XFS_ALLOC_KTRACE_UNBUSY 5 121#define XFS_ALLOC_KTRACE_BUSYSEARCH 6 122#endif 123 124/* 125 * Compute and fill in value of m_ag_maxlevels. 126 */ 127void 128xfs_alloc_compute_maxlevels( 129 struct xfs_mount *mp); /* file system mount structure */ 130 131/* 132 * Get a block from the freelist. 133 * Returns with the buffer for the block gotten. 134 */ 135int /* error */ 136xfs_alloc_get_freelist( 137 struct xfs_trans *tp, /* transaction pointer */ 138 struct xfs_buf *agbp, /* buffer containing the agf structure */ 139 xfs_agblock_t *bnop); /* block address retrieved from freelist */ 140 141/* 142 * Log the given fields from the agf structure. 143 */ 144void 145xfs_alloc_log_agf( 146 struct xfs_trans *tp, /* transaction pointer */ 147 struct xfs_buf *bp, /* buffer for a.g. freelist header */ 148 int fields);/* mask of fields to be logged (XFS_AGF_...) */ 149 150/* 151 * Interface for inode allocation to force the pag data to be initialized. 152 */ 153int /* error */ 154xfs_alloc_pagf_init( 155 struct xfs_mount *mp, /* file system mount structure */ 156 struct xfs_trans *tp, /* transaction pointer */ 157 xfs_agnumber_t agno, /* allocation group number */ 158 int flags); /* XFS_ALLOC_FLAGS_... */ 159 160/* 161 * Put the block on the freelist for the allocation group. 162 */ 163int /* error */ 164xfs_alloc_put_freelist( 165 struct xfs_trans *tp, /* transaction pointer */ 166 struct xfs_buf *agbp, /* buffer for a.g. freelist header */ 167 struct xfs_buf *agflbp,/* buffer for a.g. free block array */ 168 xfs_agblock_t bno); /* block being freed */ 169 170/* 171 * Read in the allocation group header (free/alloc section). 172 */ 173int /* error */ 174xfs_alloc_read_agf( 175 struct xfs_mount *mp, /* mount point structure */ 176 struct xfs_trans *tp, /* transaction pointer */ 177 xfs_agnumber_t agno, /* allocation group number */ 178 int flags, /* XFS_ALLOC_FLAG_... */ 179 struct xfs_buf **bpp); /* buffer for the ag freelist header */ 180 181/* 182 * Allocate an extent (variable-size). 183 */ 184int /* error */ 185xfs_alloc_vextent( 186 xfs_alloc_arg_t *args); /* allocation argument structure */ 187 188/* 189 * Free an extent. 190 */ 191int /* error */ 192xfs_free_extent( 193 struct xfs_trans *tp, /* transaction pointer */ 194 xfs_fsblock_t bno, /* starting block number of extent */ 195 xfs_extlen_t len); /* length of extent */ 196 197void 198xfs_alloc_mark_busy(xfs_trans_t *tp, 199 xfs_agnumber_t agno, 200 xfs_agblock_t bno, 201 xfs_extlen_t len); 202 203void 204xfs_alloc_clear_busy(xfs_trans_t *tp, 205 xfs_agnumber_t ag, 206 int idx); 207 208 209#endif /* __KERNEL__ */ 210 211#endif /* __XFS_ALLOC_H__ */ 212