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