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_mount;
  24 struct xfs_trans;
  25
  26 /*
  27  * Allocation parameters for inode allocation.
  28  */
  29 #define XFS_IALLOC_INODES(mp)   (mp)->m_ialloc_inos
  30 #define XFS_IALLOC_BLOCKS(mp)   (mp)->m_ialloc_blks
  31
  32 /*
  33  * Move inodes in clusters of this size.
  34  */
  35 #define XFS_INODE_BIG_CLUSTER_SIZE      8192
  36 #define XFS_INODE_CLUSTER_SIZE(mp)      (mp)->m_inode_cluster_size
  37
  38 /*
  39  * Make an inode pointer out of the buffer/offset.
  40  */
  41 #define XFS_MAKE_IPTR(mp,b,o)           xfs_make_iptr(mp,b,o)
  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  * Find a free (set) bit in the inode bitmask.
  51  */
  52 #define XFS_IALLOC_FIND_FREE(fp)        xfs_ialloc_find_free(fp)
  53 static inline int xfs_ialloc_find_free(xfs_inofree_t *fp)
  54 {
  55         return xfs_lowbit64(*fp);
  56 }
  57
  58
  59 #ifdef __KERNEL__
  60 /*
  61  * Allocate an inode on disk.
  62  * Mode is used to tell whether the new inode will need space, and whether
  63  * it is a directory.
  64  *
  65  * To work within the constraint of one allocation per transaction,
  66  * xfs_dialloc() is designed to be called twice if it has to do an
  67  * allocation to make more free inodes.  If an inode is
  68  * available without an allocation, agbp would be set to the current
  69  * agbp and alloc_done set to false.
  70  * If an allocation needed to be done, agbp would be set to the
  71  * inode header of the allocation group and alloc_done set to true.
  72  * The caller should then commit the current transaction and allocate a new
  73  * transaction.  xfs_dialloc() should then be called again with
  74  * the agbp value returned from the previous call.
  75  *
  76  * Once we successfully pick an inode its number is returned and the
  77  * on-disk data structures are updated.  The inode itself is not read
  78  * in, since doing so would break ordering constraints with xfs_reclaim.
  79  *
  80  * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
  81  */
  82 int                                     /* error */
  83 xfs_dialloc(
  84         struct xfs_trans *tp,           /* transaction pointer */
  85         xfs_ino_t       parent,         /* parent inode (directory) */
  86         mode_t          mode,           /* mode bits for new inode */
  87         int             okalloc,        /* ok to allocate more space */
  88         struct xfs_buf  **agbp,         /* buf for a.g. inode header */
  89         boolean_t       *alloc_done,    /* an allocation was done to replenish
  90                                            the free inodes */
  91         xfs_ino_t       *inop);         /* inode number allocated */
  92
  93 /*
  94  * Free disk inode.  Carefully avoids touching the incore inode, all
  95  * manipulations incore are the caller's responsibility.
  96  * The on-disk inode is not changed by this operation, only the
  97  * btree (free inode mask) is changed.
  98  */
  99 int                                     /* error */
 100 xfs_difree(
 101         struct xfs_trans *tp,           /* transaction pointer */
 102         xfs_ino_t       inode,          /* inode to be freed */
 103         struct xfs_bmap_free *flist,    /* extents to free */
 104         int             *delete,        /* set if inode cluster was deleted */
 105         xfs_ino_t       *first_ino);    /* first inode in deleted cluster */
 106
 107 /*
 108  * Return the location of the inode in bno/len/off,
 109  * for mapping it into a buffer.
 110  */
 111 int
 112 xfs_dilocate(
 113         struct xfs_mount *mp,           /* file system mount structure */
 114         struct xfs_trans *tp,           /* transaction pointer */
 115         xfs_ino_t       ino,            /* inode to locate */
 116         xfs_fsblock_t   *bno,           /* output: block containing inode */
 117         int             *len,           /* output: num blocks in cluster*/
 118         int             *off,           /* output: index in block of inode */
 119         uint            flags);         /* flags for inode btree lookup */
 120
 121 /*
 122  * Compute and fill in value of m_in_maxlevels.
 123  */
 124 void
 125 xfs_ialloc_compute_maxlevels(
 126         struct xfs_mount *mp);          /* file system mount structure */
 127
 128 /*
 129  * Log specified fields for the ag hdr (inode section)
 130  */
 131 void
 132 xfs_ialloc_log_agi(
 133         struct xfs_trans *tp,           /* transaction pointer */
 134         struct xfs_buf  *bp,            /* allocation group header buffer */
 135         int             fields);        /* bitmask of fields to log */
 136
 137 /*
 138  * Read in the allocation group header (inode allocation section)
 139  */
 140 int                                     /* error */
 141 xfs_ialloc_read_agi(
 142         struct xfs_mount *mp,           /* file system mount structure */
 143         struct xfs_trans *tp,           /* transaction pointer */
 144         xfs_agnumber_t  agno,           /* allocation group number */
 145         struct xfs_buf  **bpp);         /* allocation group hdr buf */
 146
 147 /*
 148  * Read in the allocation group header to initialise the per-ag data
 149  * in the mount structure
 150  */
 151 int
 152 xfs_ialloc_pagi_init(
 153         struct xfs_mount *mp,           /* file system mount structure */
 154         struct xfs_trans *tp,           /* transaction pointer */
 155         xfs_agnumber_t  agno);          /* allocation group number */
 156
 157 #endif  /* __KERNEL__ */
 158
 159 #endif  /* __XFS_IALLOC_H__ */