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; 25struct xfs_busy_extent; 26 27/* 28 * Freespace allocation types. Argument to xfs_alloc_[v]extent. 29 */ 30#define XFS_ALLOCTYPE_ANY_AG 0x01 /* allocate anywhere, use rotor */ 31#define XFS_ALLOCTYPE_FIRST_AG 0x02 /* ... start at ag 0 */ 32#define XFS_ALLOCTYPE_START_AG 0x04 /* anywhere, start in this a.g. */ 33#define XFS_ALLOCTYPE_THIS_AG 0x08 /* anywhere in this a.g. */ 34#define XFS_ALLOCTYPE_START_BNO 0x10 /* near this block else anywhere */ 35#define XFS_ALLOCTYPE_NEAR_BNO 0x20 /* in this a.g. and near this block */ 36#define XFS_ALLOCTYPE_THIS_BNO 0x40 /* at exactly this block */ 37 38/* this should become an enum again when the tracing code is fixed */ 39typedef unsigned int xfs_alloctype_t; 40 41#define XFS_ALLOC_TYPES \ 42 { XFS_ALLOCTYPE_ANY_AG, "ANY_AG" }, \ 43 { XFS_ALLOCTYPE_FIRST_AG, "FIRST_AG" }, \ 44 { XFS_ALLOCTYPE_START_AG, "START_AG" }, \ 45 { XFS_ALLOCTYPE_THIS_AG, "THIS_AG" }, \ 46 { XFS_ALLOCTYPE_START_BNO, "START_BNO" }, \ 47 { XFS_ALLOCTYPE_NEAR_BNO, "NEAR_BNO" }, \ 48 { XFS_ALLOCTYPE_THIS_BNO, "THIS_BNO" } 49 50/* 51 * Flags for xfs_alloc_fix_freelist. 52 */ 53#define XFS_ALLOC_FLAG_TRYLOCK 0x00000001 /* use trylock for buffer locking */ 54#define XFS_ALLOC_FLAG_FREEING 0x00000002 /* indicate caller is freeing extents*/ 55 56/* 57 * In order to avoid ENOSPC-related deadlock caused by 58 * out-of-order locking of AGF buffer (PV 947395), we place 59 * constraints on the relationship among actual allocations for 60 * data blocks, freelist blocks, and potential file data bmap 61 * btree blocks. However, these restrictions may result in no 62 * actual space allocated for a delayed extent, for example, a data 63 * block in a certain AG is allocated but there is no additional 64 * block for the additional bmap btree block due to a split of the 65 * bmap btree of the file. The result of this may lead to an 66 * infinite loop in xfssyncd when the file gets flushed to disk and 67 * all delayed extents need to be actually allocated. To get around 68 * this, we explicitly set aside a few blocks which will not be 69 * reserved in delayed allocation. Considering the minimum number of 70 * needed freelist blocks is 4 fsbs _per AG_, a potential split of file's bmap 71 * btree requires 1 fsb, so we set the number of set-aside blocks 72 * to 4 + 4*agcount. 73 */ 74#define XFS_ALLOC_SET_ASIDE(mp) (4 + ((mp)->m_sb.sb_agcount * 4)) 75 76/* 77 * Argument structure for xfs_alloc routines. 78 * This is turned into a structure to avoid having 20 arguments passed 79 * down several levels of the stack. 80 */ 81typedef struct xfs_alloc_arg { 82 struct xfs_trans *tp; /* transaction pointer */ 83 struct xfs_mount *mp; /* file system mount point */ 84 struct xfs_buf *agbp; /* buffer for a.g. freelist header */ 85 struct xfs_perag *pag; /* per-ag struct for this agno */ 86 xfs_fsblock_t fsbno; /* file system block number */ 87 xfs_agnumber_t agno; /* allocation group number */ 88 xfs_agblock_t agbno; /* allocation group-relative block # */ 89 xfs_extlen_t minlen; /* minimum size of extent */ 90 xfs_extlen_t maxlen; /* maximum size of extent */ 91 xfs_extlen_t mod; /* mod value for extent size */ 92 xfs_extlen_t prod; /* prod value for extent size */ 93 xfs_extlen_t minleft; /* min blocks must be left after us */ 94 xfs_extlen_t total; /* total blocks needed in xaction */ 95 xfs_extlen_t alignment; /* align answer to multiple of this */ 96 xfs_extlen_t minalignslop; /* slop for minlen+alignment calcs */ 97 xfs_extlen_t len; /* output: actual size of extent */ 98 xfs_alloctype_t type; /* allocation type XFS_ALLOCTYPE_... */ 99 xfs_alloctype_t otype; /* original allocation type */ 100 char wasdel; /* set if allocation was prev delayed */ 101 char wasfromfl; /* set if allocation is from freelist */ 102 char isfl; /* set if is freelist blocks - !acctg */ 103 char userdata; /* set if this is user data */ 104 xfs_fsblock_t firstblock; /* io first block allocated */ 105} xfs_alloc_arg_t; 106 107/* 108 * Defines for userdata 109 */ 110#define XFS_ALLOC_USERDATA 1 /* allocation is for user data*/ 111#define XFS_ALLOC_INITIAL_USER_DATA 2 /* special case start of file */ 112 113/* 114 * Find the length of the longest extent in an AG. 115 */ 116xfs_extlen_t 117xfs_alloc_longest_free_extent(struct xfs_mount *mp, 118 struct xfs_perag *pag); 119 120#ifdef __KERNEL__ 121 122void 123xfs_alloc_busy_insert(xfs_trans_t *tp, 124 xfs_agnumber_t agno, 125 xfs_agblock_t bno, 126 xfs_extlen_t len); 127 128void 129xfs_alloc_busy_clear(struct xfs_mount *mp, struct xfs_busy_extent *busyp); 130 131#endif /* __KERNEL__ */ 132 133/* 134 * Compute and fill in value of m_ag_maxlevels. 135 */ 136void 137xfs_alloc_compute_maxlevels( 138 struct xfs_mount *mp); /* file system mount structure */ 139 140/* 141 * Get a block from the freelist. 142 * Returns with the buffer for the block gotten. 143 */ 144int /* error */ 145xfs_alloc_get_freelist( 146 struct xfs_trans *tp, /* transaction pointer */ 147 struct xfs_buf *agbp, /* buffer containing the agf structure */ 148 xfs_agblock_t *bnop, /* block address retrieved from freelist */ 149 int btreeblk); /* destination is a AGF btree */ 150 151/* 152 * Log the given fields from the agf structure. 153 */ 154void 155xfs_alloc_log_agf( 156 struct xfs_trans *tp, /* transaction pointer */ 157 struct xfs_buf *bp, /* buffer for a.g. freelist header */ 158 int fields);/* mask of fields to be logged (XFS_AGF_...) */ 159 160/* 161 * Interface for inode allocation to force the pag data to be initialized. 162 */ 163int /* error */ 164xfs_alloc_pagf_init( 165 struct xfs_mount *mp, /* file system mount structure */ 166 struct xfs_trans *tp, /* transaction pointer */ 167 xfs_agnumber_t agno, /* allocation group number */ 168 int flags); /* XFS_ALLOC_FLAGS_... */ 169 170/* 171 * Put the block on the freelist for the allocation group. 172 */ 173int /* error */ 174xfs_alloc_put_freelist( 175 struct xfs_trans *tp, /* transaction pointer */ 176 struct xfs_buf *agbp, /* buffer for a.g. freelist header */ 177 struct xfs_buf *agflbp,/* buffer for a.g. free block array */ 178 xfs_agblock_t bno, /* block being freed */ 179 int btreeblk); /* owner was a AGF btree */ 180 181/* 182 * Read in the allocation group header (free/alloc section). 183 */ 184int /* error */ 185xfs_alloc_read_agf( 186 struct xfs_mount *mp, /* mount point structure */ 187 struct xfs_trans *tp, /* transaction pointer */ 188 xfs_agnumber_t agno, /* allocation group number */ 189 int flags, /* XFS_ALLOC_FLAG_... */ 190 struct xfs_buf **bpp); /* buffer for the ag freelist header */ 191 192/* 193 * Allocate an extent (variable-size). 194 */ 195int /* error */ 196xfs_alloc_vextent( 197 xfs_alloc_arg_t *args); /* allocation argument structure */ 198 199/* 200 * Free an extent. 201 */ 202int /* error */ 203xfs_free_extent( 204 struct xfs_trans *tp, /* transaction pointer */ 205 xfs_fsblock_t bno, /* starting block number of extent */ 206 xfs_extlen_t len); /* length of extent */ 207 208#endif /* __XFS_ALLOC_H__ */ 209