fs/xfs/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 struct xfs_icluster {
  32         bool            deleted;        /* record is deleted */
  33         xfs_ino_t       first_ino;      /* first inode number */
  34         uint64_t        alloc;          /* inode phys. allocation bitmap for
  35                                          * sparse chunks */
  36 };
  37
  38 /* Calculate and return the number of filesystem blocks per inode cluster */
  39 static inline int
  40 xfs_icluster_size_fsb(
  41         struct xfs_mount        *mp)
  42 {
  43         if (mp->m_sb.sb_blocksize >= mp->m_inode_cluster_size)
  44                 return 1;
  45         return mp->m_inode_cluster_size >> mp->m_sb.sb_blocklog;
  46 }
  47
  48 /*
  49  * Make an inode pointer out of the buffer/offset.
  50  */
  51 static inline struct xfs_dinode *
  52 xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o)
  53 {
  54         return xfs_buf_offset(b, o << (mp)->m_sb.sb_inodelog);
  55 }
  56
  57 /*
  58  * Allocate an inode on disk.
  59  * Mode is used to tell whether the new inode will need space, and whether
  60  * it is a directory.
  61  *
  62  * To work within the constraint of one allocation per transaction,
  63  * xfs_dialloc() is designed to be called twice if it has to do an
  64  * allocation to make more free inodes.  If an inode is
  65  * available without an allocation, agbp would be set to the current
  66  * agbp and alloc_done set to false.
  67  * If an allocation needed to be done, agbp would be set to the
  68  * inode header of the allocation group and alloc_done set to true.
  69  * The caller should then commit the current transaction and allocate a new
  70  * transaction.  xfs_dialloc() should then be called again with
  71  * the agbp value returned from the previous call.
  72  *
  73  * Once we successfully pick an inode its number is returned and the
  74  * on-disk data structures are updated.  The inode itself is not read
  75  * in, since doing so would break ordering constraints with xfs_reclaim.
  76  *
  77  * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
  78  */
  79 int                                     /* error */
  80 xfs_dialloc(
  81         struct xfs_trans *tp,           /* transaction pointer */
  82         xfs_ino_t       parent,         /* parent inode (directory) */
  83         umode_t         mode,           /* mode bits for new inode */
  84         int             okalloc,        /* ok to allocate more space */
  85         struct xfs_buf  **agbp,         /* buf for a.g. inode header */
  86         xfs_ino_t       *inop);         /* inode number allocated */
  87
  88 /*
  89  * Free disk inode.  Carefully avoids touching the incore inode, all
  90  * manipulations incore are the caller's responsibility.
  91  * The on-disk inode is not changed by this operation, only the
  92  * btree (free inode mask) is changed.
  93  */
  94 int                                     /* error */
  95 xfs_difree(
  96         struct xfs_trans *tp,           /* transaction pointer */
  97         xfs_ino_t       inode,          /* inode to be freed */
  98         struct xfs_bmap_free *flist,    /* extents to free */
  99         struct xfs_icluster *ifree);    /* cluster info if deleted */
 100
 101 /*
 102  * Return the location of the inode in imap, for mapping it into a buffer.
 103  */
 104 int
 105 xfs_imap(
 106         struct xfs_mount *mp,           /* file system mount structure */
 107         struct xfs_trans *tp,           /* transaction pointer */
 108         xfs_ino_t       ino,            /* inode to locate */
 109         struct xfs_imap *imap,          /* location map structure */
 110         uint            flags);         /* flags for inode btree lookup */
 111
 112 /*
 113  * Compute and fill in value of m_in_maxlevels.
 114  */
 115 void
 116 xfs_ialloc_compute_maxlevels(
 117         struct xfs_mount *mp);          /* file system mount structure */
 118
 119 /*
 120  * Log specified fields for the ag hdr (inode section)
 121  */
 122 void
 123 xfs_ialloc_log_agi(
 124         struct xfs_trans *tp,           /* transaction pointer */
 125         struct xfs_buf  *bp,            /* allocation group header buffer */
 126         int             fields);        /* bitmask of fields to log */
 127
 128 /*
 129  * Read in the allocation group header (inode allocation section)
 130  */
 131 int                                     /* error */
 132 xfs_ialloc_read_agi(
 133         struct xfs_mount *mp,           /* file system mount structure */
 134         struct xfs_trans *tp,           /* transaction pointer */
 135         xfs_agnumber_t  agno,           /* allocation group number */
 136         struct xfs_buf  **bpp);         /* allocation group hdr buf */
 137
 138 /*
 139  * Read in the allocation group header to initialise the per-ag data
 140  * in the mount structure
 141  */
 142 int
 143 xfs_ialloc_pagi_init(
 144         struct xfs_mount *mp,           /* file system mount structure */
 145         struct xfs_trans *tp,           /* transaction pointer */
 146         xfs_agnumber_t  agno);          /* allocation group number */
 147
 148 /*
 149  * Lookup a record by ino in the btree given by cur.
 150  */
 151 int xfs_inobt_lookup(struct xfs_btree_cur *cur, xfs_agino_t ino,
 152                 xfs_lookup_t dir, int *stat);
 153
 154 /*
 155  * Get the data from the pointed-to record.
 156  */
 157 int xfs_inobt_get_rec(struct xfs_btree_cur *cur,
 158                 xfs_inobt_rec_incore_t *rec, int *stat);
 159
 160 /*
 161  * Inode chunk initialisation routine
 162  */
 163 int xfs_ialloc_inode_init(struct xfs_mount *mp, struct xfs_trans *tp,
 164                           struct list_head *buffer_list, int icount,
 165                           xfs_agnumber_t agno, xfs_agblock_t agbno,
 166                           xfs_agblock_t length, unsigned int gen);
 167
 168 int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp,
 169                 xfs_agnumber_t agno, struct xfs_buf **bpp);
 170
 171
 172 #endif  /* __XFS_IALLOC_H__ */