fs/xfs/libxfs/xfs_bmap.h

   1 /*
   2  * Copyright (c) 2000-2006 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_BMAP_H__
  19 #define __XFS_BMAP_H__
  20
  21 struct getbmap;
  22 struct xfs_bmbt_irec;
  23 struct xfs_ifork;
  24 struct xfs_inode;
  25 struct xfs_mount;
  26 struct xfs_trans;
  27
  28 extern kmem_zone_t      *xfs_bmap_free_item_zone;
  29
  30 /*
  31  * Argument structure for xfs_bmap_alloc.
  32  */
  33 struct xfs_bmalloca {
  34         xfs_fsblock_t           *firstblock; /* i/o first block allocated */
  35         struct xfs_defer_ops    *dfops; /* bmap freelist */
  36         struct xfs_trans        *tp;    /* transaction pointer */
  37         struct xfs_inode        *ip;    /* incore inode pointer */
  38         struct xfs_bmbt_irec    prev;   /* extent before the new one */
  39         struct xfs_bmbt_irec    got;    /* extent after, or delayed */
  40
  41         xfs_fileoff_t           offset; /* offset in file filling in */
  42         xfs_extlen_t            length; /* i/o length asked/allocated */
  43         xfs_fsblock_t           blkno;  /* starting block of new extent */
  44
  45         struct xfs_btree_cur    *cur;   /* btree cursor */
  46         xfs_extnum_t            idx;    /* current extent index */
  47         int                     nallocs;/* number of extents alloc'd */
  48         int                     logflags;/* flags for transaction logging */
  49
  50         xfs_extlen_t            total;  /* total blocks needed for xaction */
  51         xfs_extlen_t            minlen; /* minimum allocation size (blocks) */
  52         xfs_extlen_t            minleft; /* amount must be left after alloc */
  53         bool                    eof;    /* set if allocating past last extent */
  54         bool                    wasdel; /* replacing a delayed allocation */
  55         bool                    aeof;   /* allocated space at eof */
  56         bool                    conv;   /* overwriting unwritten extents */
  57         char                    userdata;/* userdata mask */
  58         int                     flags;
  59 };
  60
  61 /*
  62  * List of extents to be free "later".
  63  * The list is kept sorted on xbf_startblock.
  64  */
  65 struct xfs_extent_free_item
  66 {
  67         xfs_fsblock_t           xefi_startblock;/* starting fs block number */
  68         xfs_extlen_t            xefi_blockcount;/* number of blocks in extent */
  69         struct list_head        xefi_list;
  70 };
  71
  72 #define XFS_BMAP_MAX_NMAP       4
  73
  74 /*
  75  * Flags for xfs_bmapi_*
  76  */
  77 #define XFS_BMAPI_ENTIRE        0x001   /* return entire extent, not trimmed */
  78 #define XFS_BMAPI_METADATA      0x002   /* mapping metadata not user data */
  79 #define XFS_BMAPI_ATTRFORK      0x004   /* use attribute fork not data */
  80 #define XFS_BMAPI_PREALLOC      0x008   /* preallocation op: unwritten space */
  81 #define XFS_BMAPI_IGSTATE       0x010   /* Ignore state - */
  82                                         /* combine contig. space */
  83 #define XFS_BMAPI_CONTIG        0x020   /* must allocate only one extent */
  84 /*
  85  * unwritten extent conversion - this needs write cache flushing and no additional
  86  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
  87  * from written to unwritten, otherwise convert from unwritten to written.
  88  */
  89 #define XFS_BMAPI_CONVERT       0x040
  90
  91 /*
  92  * allocate zeroed extents - this requires all newly allocated user data extents
  93  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
  94  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
  95  * during the allocation range to zeroed written extents.
  96  */
  97 #define XFS_BMAPI_ZERO          0x080
  98
  99 #define XFS_BMAPI_FLAGS \
 100         { XFS_BMAPI_ENTIRE,     "ENTIRE" }, \
 101         { XFS_BMAPI_METADATA,   "METADATA" }, \
 102         { XFS_BMAPI_ATTRFORK,   "ATTRFORK" }, \
 103         { XFS_BMAPI_PREALLOC,   "PREALLOC" }, \
 104         { XFS_BMAPI_IGSTATE,    "IGSTATE" }, \
 105         { XFS_BMAPI_CONTIG,     "CONTIG" }, \
 106         { XFS_BMAPI_CONVERT,    "CONVERT" }, \
 107         { XFS_BMAPI_ZERO,       "ZERO" }
 108
 109
 110 static inline int xfs_bmapi_aflag(int w)
 111 {
 112         return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
 113 }
 114
 115 /*
 116  * Special values for xfs_bmbt_irec_t br_startblock field.
 117  */
 118 #define DELAYSTARTBLOCK         ((xfs_fsblock_t)-1LL)
 119 #define HOLESTARTBLOCK          ((xfs_fsblock_t)-2LL)
 120
 121 /*
 122  * Flags for xfs_bmap_add_extent*.
 123  */
 124 #define BMAP_LEFT_CONTIG        (1 << 0)
 125 #define BMAP_RIGHT_CONTIG       (1 << 1)
 126 #define BMAP_LEFT_FILLING       (1 << 2)
 127 #define BMAP_RIGHT_FILLING      (1 << 3)
 128 #define BMAP_LEFT_DELAY         (1 << 4)
 129 #define BMAP_RIGHT_DELAY        (1 << 5)
 130 #define BMAP_LEFT_VALID         (1 << 6)
 131 #define BMAP_RIGHT_VALID        (1 << 7)
 132 #define BMAP_ATTRFORK           (1 << 8)
 133
 134 #define XFS_BMAP_EXT_FLAGS \
 135         { BMAP_LEFT_CONTIG,     "LC" }, \
 136         { BMAP_RIGHT_CONTIG,    "RC" }, \
 137         { BMAP_LEFT_FILLING,    "LF" }, \
 138         { BMAP_RIGHT_FILLING,   "RF" }, \
 139         { BMAP_ATTRFORK,        "ATTR" }
 140
 141
 142 /*
 143  * This macro is used to determine how many extents will be shifted
 144  * in one write transaction. We could require two splits,
 145  * an extent move on the first and an extent merge on the second,
 146  * So it is proper that one extent is shifted inside write transaction
 147  * at a time.
 148  */
 149 #define XFS_BMAP_MAX_SHIFT_EXTENTS      1
 150
 151 enum shift_direction {
 152         SHIFT_LEFT = 0,
 153         SHIFT_RIGHT,
 154 };
 155
 156 #ifdef DEBUG
 157 void    xfs_bmap_trace_exlist(struct xfs_inode *ip, xfs_extnum_t cnt,
 158                 int whichfork, unsigned long caller_ip);
 159 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)   \
 160         xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
 161 #else
 162 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)
 163 #endif
 164
 165 int     xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
 166 void    xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
 167 void    xfs_bmap_add_free(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 168                           xfs_fsblock_t bno, xfs_filblks_t len);
 169 void    xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
 170 int     xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
 171                 xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
 172 int     xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
 173                 xfs_fileoff_t *last_block, int whichfork);
 174 int     xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
 175                 int whichfork);
 176 int     xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
 177 int     xfs_bmap_read_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 178                 int whichfork);
 179 int     xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
 180                 xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 181                 int *nmap, int flags);
 182 int     xfs_bmapi_delay(struct xfs_inode *ip, xfs_fileoff_t bno,
 183                 xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 184                 int *nmap, int flags);
 185 int     xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
 186                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 187                 xfs_fsblock_t *firstblock, xfs_extlen_t total,
 188                 struct xfs_bmbt_irec *mval, int *nmap,
 189                 struct xfs_defer_ops *dfops);
 190 int     xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 191                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 192                 xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
 193                 struct xfs_defer_ops *dfops, int *done);
 194 int     xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
 195                 xfs_extnum_t num);
 196 uint    xfs_default_attroffset(struct xfs_inode *ip);
 197 int     xfs_bmap_shift_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 198                 xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
 199                 int *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
 200                 struct xfs_defer_ops *dfops, enum shift_direction direction,
 201                 int num_exts);
 202 int     xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
 203
 204 #endif  /* __XFS_BMAP_H__ */