include/xfs_ialloc.h

   1 /*
   2  * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it would be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11  *
  12  * Further, this software is distributed without any warranty that it is
  13  * free of the rightful claim of any third person regarding infringement
  14  * or the like.  Any license provided herein, whether implied or
  15  * otherwise, applies only to this software file.  Patent licenses, if
  16  * any, provided herein do not apply to combinations of this program with
  17  * other software, or any other product whatsoever.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write the Free Software Foundation, Inc., 59
  21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24  * Mountain View, CA  94043, or:
  25  *
  26  * http://www.sgi.com
  27  *
  28  * For further information regarding this notice, see:
  29  *
  30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31  */
  32 #ifndef __XFS_IALLOC_H__
  33 #define __XFS_IALLOC_H__
  34
  35 struct xfs_buf;
  36 struct xfs_dinode;
  37 struct xfs_mount;
  38 struct xfs_trans;
  39
  40 /*
  41  * Allocation parameters for inode allocation.
  42  */
  43 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_IALLOC_INODES)
  44 int xfs_ialloc_inodes(struct xfs_mount *mp);
  45 #define XFS_IALLOC_INODES(mp)   xfs_ialloc_inodes(mp)
  46 #else
  47 #define XFS_IALLOC_INODES(mp)   ((mp)->m_ialloc_inos)
  48 #endif
  49 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_IALLOC_BLOCKS)
  50 xfs_extlen_t xfs_ialloc_blocks(struct xfs_mount *mp);
  51 #define XFS_IALLOC_BLOCKS(mp)   xfs_ialloc_blocks(mp)
  52 #else
  53 #define XFS_IALLOC_BLOCKS(mp)   ((mp)->m_ialloc_blks)
  54 #endif
  55
  56 /*
  57  * For small block file systems, move inodes in clusters of this size.
  58  * When we don't have a lot of memory, however, we go a bit smaller
  59  * to reduce the number of AGI and ialloc btree blocks we need to keep
  60  * around for xfs_dilocate().  We choose which one to use in
  61  * xfs_mount_int().
  62  */
  63 #define XFS_INODE_BIG_CLUSTER_SIZE      8192
  64 #define XFS_INODE_SMALL_CLUSTER_SIZE    4096
  65 #define XFS_INODE_CLUSTER_SIZE(mp)      (mp)->m_inode_cluster_size
  66
  67 /*
  68  * Make an inode pointer out of the buffer/offset.
  69  */
  70 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MAKE_IPTR)
  71 struct xfs_dinode *xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o);
  72 #define XFS_MAKE_IPTR(mp,b,o)           xfs_make_iptr(mp,b,o)
  73 #else
  74 #define XFS_MAKE_IPTR(mp,b,o) \
  75         ((xfs_dinode_t *)(xfs_buf_offset(b, (o) << (mp)->m_sb.sb_inodelog)))
  76 #endif
  77
  78 /*
  79  * Find a free (set) bit in the inode bitmask.
  80  */
  81 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_IALLOC_FIND_FREE)
  82 int xfs_ialloc_find_free(xfs_inofree_t *fp);
  83 #define XFS_IALLOC_FIND_FREE(fp)        xfs_ialloc_find_free(fp)
  84 #else
  85 #define XFS_IALLOC_FIND_FREE(fp)        xfs_lowbit64(*(fp))
  86 #endif
  87
  88
  89 #ifdef __KERNEL__
  90
  91 /*
  92  * Prototypes for visible xfs_ialloc.c routines.
  93  */
  94
  95 /*
  96  * Allocate an inode on disk.
  97  * Mode is used to tell whether the new inode will need space, and whether
  98  * it is a directory.
  99  *
 100  * To work within the constraint of one allocation per transaction,
 101  * xfs_dialloc() is designed to be called twice if it has to do an
 102  * allocation to make more free inodes.  If an inode is
 103  * available without an allocation, agbp would be set to the current
 104  * agbp and alloc_done set to false.
 105  * If an allocation needed to be done, agbp would be set to the
 106  * inode header of the allocation group and alloc_done set to true.
 107  * The caller should then commit the current transaction and allocate a new
 108  * transaction.  xfs_dialloc() should then be called again with
 109  * the agbp value returned from the previous call.
 110  *
 111  * Once we successfully pick an inode its number is returned and the
 112  * on-disk data structures are updated.  The inode itself is not read
 113  * in, since doing so would break ordering constraints with xfs_reclaim.
 114  *
 115  * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
 116  */
 117 int                                     /* error */
 118 xfs_dialloc(
 119         struct xfs_trans *tp,           /* transaction pointer */
 120         xfs_ino_t       parent,         /* parent inode (directory) */
 121         mode_t          mode,           /* mode bits for new inode */
 122         int             okalloc,        /* ok to allocate more space */
 123         struct xfs_buf  **agbp,         /* buf for a.g. inode header */
 124         boolean_t       *alloc_done,    /* an allocation was done to replenish
 125                                            the free inodes */
 126         xfs_ino_t       *inop);         /* inode number allocated */
 127
 128 /*
 129  * Free disk inode.  Carefully avoids touching the incore inode, all
 130  * manipulations incore are the caller's responsibility.
 131  * The on-disk inode is not changed by this operation, only the
 132  * btree (free inode mask) is changed.
 133  */
 134 int                                     /* error */
 135 xfs_difree(
 136         struct xfs_trans *tp,           /* transaction pointer */
 137         xfs_ino_t       inode);         /* inode to be freed */
 138
 139 /*
 140  * Return the location of the inode in bno/len/off,
 141  * for mapping it into a buffer.
 142  */
 143 int
 144 xfs_dilocate(
 145         struct xfs_mount *mp,           /* file system mount structure */
 146         struct xfs_trans *tp,           /* transaction pointer */
 147         xfs_ino_t       ino,            /* inode to locate */
 148         xfs_fsblock_t   *bno,           /* output: block containing inode */
 149         int             *len,           /* output: num blocks in cluster*/
 150         int             *off,           /* output: index in block of inode */
 151         uint            flags);         /* flags for inode btree lookup */
 152
 153 /*
 154  * Compute and fill in value of m_in_maxlevels.
 155  */
 156 void
 157 xfs_ialloc_compute_maxlevels(
 158         struct xfs_mount *mp);          /* file system mount structure */
 159
 160 /*
 161  * Log specified fields for the ag hdr (inode section)
 162  */
 163 void
 164 xfs_ialloc_log_agi(
 165         struct xfs_trans *tp,           /* transaction pointer */
 166         struct xfs_buf  *bp,            /* allocation group header buffer */
 167         int             fields);        /* bitmask of fields to log */
 168
 169 /*
 170  * Read in the allocation group header (inode allocation section)
 171  */
 172 int                                     /* error */
 173 xfs_ialloc_read_agi(
 174         struct xfs_mount *mp,           /* file system mount structure */
 175         struct xfs_trans *tp,           /* transaction pointer */
 176         xfs_agnumber_t  agno,           /* allocation group number */
 177         struct xfs_buf  **bpp);         /* allocation group hdr buf */
 178
 179 #endif  /* __KERNEL__ */
 180
 181 #endif  /* __XFS_IALLOC_H__ */