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