libxfs/xfs_ialloc.h

   1 /*
   2  * Copyright (c) 2000,2005 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_IALLOC_H__
  19 #define __XFS_IALLOC_H__
  20
  21 struct xfs_buf;
  22 struct xfs_dinode;
  23 struct xfs_imap;
  24 struct xfs_mount;
  25 struct xfs_trans;
  26 struct xfs_btree_cur;
  27
  28 /* Move inodes in clusters of this size */
  29 #define XFS_INODE_BIG_CLUSTER_SIZE      8192
  30
  31 /* Calculate and return the number of filesystem blocks per inode cluster */
  32 static inline int
  33 xfs_icluster_size_fsb(
  34         struct xfs_mount        *mp)
  35 {
  36         if (mp->m_sb.sb_blocksize >= mp->m_inode_cluster_size)
  37                 return 1;
  38         return mp->m_inode_cluster_size >> mp->m_sb.sb_blocklog;
  39 }
  40
  41 /*
  42  * Make an inode pointer out of the buffer/offset.
  43  */
  44 static inline struct xfs_dinode *
  45 xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o)
  46 {
  47         return (struct xfs_dinode *)
  48                 (xfs_buf_offset(b, o << (mp)->m_sb.sb_inodelog));
  49 }
  50
  51 /*
  52  * Allocate an inode on disk.
  53  * Mode is used to tell whether the new inode will need space, and whether
  54  * it is a directory.
  55  *
  56  * To work within the constraint of one allocation per transaction,
  57  * xfs_dialloc() is designed to be called twice if it has to do an
  58  * allocation to make more free inodes.  If an inode is
  59  * available without an allocation, agbp would be set to the current
  60  * agbp and alloc_done set to false.
  61  * If an allocation needed to be done, agbp would be set to the
  62  * inode header of the allocation group and alloc_done set to true.
  63  * The caller should then commit the current transaction and allocate a new
  64  * transaction.  xfs_dialloc() should then be called again with
  65  * the agbp value returned from the previous call.
  66  *
  67  * Once we successfully pick an inode its number is returned and the
  68  * on-disk data structures are updated.  The inode itself is not read
  69  * in, since doing so would break ordering constraints with xfs_reclaim.
  70  *
  71  * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
  72  */
  73 int                                     /* error */
  74 xfs_dialloc(
  75         struct xfs_trans *tp,           /* transaction pointer */
  76         xfs_ino_t       parent,         /* parent inode (directory) */
  77         umode_t         mode,           /* mode bits for new inode */
  78         int             okalloc,        /* ok to allocate more space */
  79         struct xfs_buf  **agbp,         /* buf for a.g. inode header */
  80         xfs_ino_t       *inop);         /* inode number allocated */
  81
  82 /*
  83  * Free disk inode.  Carefully avoids touching the incore inode, all
  84  * manipulations incore are the caller's responsibility.
  85  * The on-disk inode is not changed by this operation, only the
  86  * btree (free inode mask) is changed.
  87  */
  88 int                                     /* error */
  89 xfs_difree(
  90         struct xfs_trans *tp,           /* transaction pointer */
  91         xfs_ino_t       inode,          /* inode to be freed */
  92         struct xfs_bmap_free *flist,    /* extents to free */
  93         int             *deleted,       /* set if inode cluster was deleted */
  94         xfs_ino_t       *first_ino);    /* first inode in deleted cluster */
  95
  96 /*
  97  * Return the location of the inode in imap, for mapping it into a buffer.
  98  */
  99 int
 100 xfs_imap(
 101         struct xfs_mount *mp,           /* file system mount structure */
 102         struct xfs_trans *tp,           /* transaction pointer */
 103         xfs_ino_t       ino,            /* inode to locate */
 104         struct xfs_imap *imap,          /* location map structure */
 105         uint            flags);         /* flags for inode btree lookup */
 106
 107 /*
 108  * Compute and fill in value of m_in_maxlevels.
 109  */
 110 void
 111 xfs_ialloc_compute_maxlevels(
 112         struct xfs_mount *mp);          /* file system mount structure */
 113
 114 /*
 115  * Log specified fields for the ag hdr (inode section)
 116  */
 117 void
 118 xfs_ialloc_log_agi(
 119         struct xfs_trans *tp,           /* transaction pointer */
 120         struct xfs_buf  *bp,            /* allocation group header buffer */
 121         int             fields);        /* bitmask of fields to log */
 122
 123 /*
 124  * Read in the allocation group header (inode allocation section)
 125  */
 126 int                                     /* error */
 127 xfs_ialloc_read_agi(
 128         struct xfs_mount *mp,           /* file system mount structure */
 129         struct xfs_trans *tp,           /* transaction pointer */
 130         xfs_agnumber_t  agno,           /* allocation group number */
 131         struct xfs_buf  **bpp);         /* allocation group hdr buf */
 132
 133 /*
 134  * Read in the allocation group header to initialise the per-ag data
 135  * in the mount structure
 136  */
 137 int
 138 xfs_ialloc_pagi_init(
 139         struct xfs_mount *mp,           /* file system mount structure */
 140         struct xfs_trans *tp,           /* transaction pointer */
 141         xfs_agnumber_t  agno);          /* allocation group number */
 142
 143 /*
 144  * Lookup a record by ino in the btree given by cur.
 145  */
 146 int xfs_inobt_lookup(struct xfs_btree_cur *cur, xfs_agino_t ino,
 147                 xfs_lookup_t dir, int *stat);
 148
 149 /*
 150  * Get the data from the pointed-to record.
 151  */
 152 int xfs_inobt_get_rec(struct xfs_btree_cur *cur,
 153                 xfs_inobt_rec_incore_t *rec, int *stat);
 154
 155 /*
 156  * Inode chunk initialisation routine
 157  */
 158 int xfs_ialloc_inode_init(struct xfs_mount *mp, struct xfs_trans *tp,
 159                           struct list_head *buffer_list, int icount,
 160                           xfs_agnumber_t agno, xfs_agblock_t agbno,
 161                           xfs_agblock_t length, unsigned int gen);
 162
 163 int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp,
 164                 xfs_agnumber_t agno, struct xfs_buf **bpp);
 165
 166
 167 #endif  /* __XFS_IALLOC_H__ */