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         int                     datatype;/* data type being allocated */
  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         struct xfs_owner_info   xefi_oinfo;     /* extent owner */
  71 };
  72
  73 #define XFS_BMAP_MAX_NMAP       4
  74
  75 /*
  76  * Flags for xfs_bmapi_*
  77  */
  78 #define XFS_BMAPI_ENTIRE        0x001   /* return entire extent, not trimmed */
  79 #define XFS_BMAPI_METADATA      0x002   /* mapping metadata not user data */
  80 #define XFS_BMAPI_ATTRFORK      0x004   /* use attribute fork not data */
  81 #define XFS_BMAPI_PREALLOC      0x008   /* preallocation op: unwritten space */
  82 #define XFS_BMAPI_IGSTATE       0x010   /* Ignore state - */
  83                                         /* combine contig. space */
  84 #define XFS_BMAPI_CONTIG        0x020   /* must allocate only one extent */
  85 /*
  86  * unwritten extent conversion - this needs write cache flushing and no additional
  87  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
  88  * from written to unwritten, otherwise convert from unwritten to written.
  89  */
  90 #define XFS_BMAPI_CONVERT       0x040
  91
  92 /*
  93  * allocate zeroed extents - this requires all newly allocated user data extents
  94  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
  95  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
  96  * during the allocation range to zeroed written extents.
  97  */
  98 #define XFS_BMAPI_ZERO          0x080
  99
 100 /*
 101  * Map the inode offset to the block given in ap->firstblock.  Primarily
 102  * used for reflink.  The range must be in a hole, and this flag cannot be
 103  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
 104  *
 105  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
 106  * refcount, or freeing the blocks.
 107  */
 108 #define XFS_BMAPI_REMAP         0x100
 109
 110 /* Map something in the CoW fork. */
 111 #define XFS_BMAPI_COWFORK       0x200
 112
 113 #define XFS_BMAPI_FLAGS \
 114         { XFS_BMAPI_ENTIRE,     "ENTIRE" }, \
 115         { XFS_BMAPI_METADATA,   "METADATA" }, \
 116         { XFS_BMAPI_ATTRFORK,   "ATTRFORK" }, \
 117         { XFS_BMAPI_PREALLOC,   "PREALLOC" }, \
 118         { XFS_BMAPI_IGSTATE,    "IGSTATE" }, \
 119         { XFS_BMAPI_CONTIG,     "CONTIG" }, \
 120         { XFS_BMAPI_CONVERT,    "CONVERT" }, \
 121         { XFS_BMAPI_ZERO,       "ZERO" }, \
 122         { XFS_BMAPI_REMAP,      "REMAP" }, \
 123         { XFS_BMAPI_COWFORK,    "COWFORK" }
 124
 125
 126 static inline int xfs_bmapi_aflag(int w)
 127 {
 128         return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
 129                (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
 130 }
 131
 132 static inline int xfs_bmapi_whichfork(int bmapi_flags)
 133 {
 134         if (bmapi_flags & XFS_BMAPI_COWFORK)
 135                 return XFS_COW_FORK;
 136         else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
 137                 return XFS_ATTR_FORK;
 138         return XFS_DATA_FORK;
 139 }
 140
 141 /*
 142  * Special values for xfs_bmbt_irec_t br_startblock field.
 143  */
 144 #define DELAYSTARTBLOCK         ((xfs_fsblock_t)-1LL)
 145 #define HOLESTARTBLOCK          ((xfs_fsblock_t)-2LL)
 146
 147 /*
 148  * Flags for xfs_bmap_add_extent*.
 149  */
 150 #define BMAP_LEFT_CONTIG        (1 << 0)
 151 #define BMAP_RIGHT_CONTIG       (1 << 1)
 152 #define BMAP_LEFT_FILLING       (1 << 2)
 153 #define BMAP_RIGHT_FILLING      (1 << 3)
 154 #define BMAP_LEFT_DELAY         (1 << 4)
 155 #define BMAP_RIGHT_DELAY        (1 << 5)
 156 #define BMAP_LEFT_VALID         (1 << 6)
 157 #define BMAP_RIGHT_VALID        (1 << 7)
 158 #define BMAP_ATTRFORK           (1 << 8)
 159 #define BMAP_COWFORK            (1 << 9)
 160
 161 #define XFS_BMAP_EXT_FLAGS \
 162         { BMAP_LEFT_CONTIG,     "LC" }, \
 163         { BMAP_RIGHT_CONTIG,    "RC" }, \
 164         { BMAP_LEFT_FILLING,    "LF" }, \
 165         { BMAP_RIGHT_FILLING,   "RF" }, \
 166         { BMAP_ATTRFORK,        "ATTR" }, \
 167         { BMAP_COWFORK,         "COW" }
 168
 169
 170 /*
 171  * This macro is used to determine how many extents will be shifted
 172  * in one write transaction. We could require two splits,
 173  * an extent move on the first and an extent merge on the second,
 174  * So it is proper that one extent is shifted inside write transaction
 175  * at a time.
 176  */
 177 #define XFS_BMAP_MAX_SHIFT_EXTENTS      1
 178
 179 enum shift_direction {
 180         SHIFT_LEFT = 0,
 181         SHIFT_RIGHT,
 182 };
 183
 184 #ifdef DEBUG
 185 void    xfs_bmap_trace_exlist(struct xfs_inode *ip, xfs_extnum_t cnt,
 186                 int whichfork, unsigned long caller_ip);
 187 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)   \
 188         xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
 189 #else
 190 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)
 191 #endif
 192
 193 int     xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
 194 void    xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
 195 void    xfs_bmap_add_free(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 196                           xfs_fsblock_t bno, xfs_filblks_t len,
 197                           struct xfs_owner_info *oinfo);
 198 void    xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
 199 int     xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
 200                 xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
 201 int     xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
 202                 xfs_fileoff_t *last_block, int whichfork);
 203 int     xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
 204                 int whichfork);
 205 int     xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
 206 int     xfs_bmap_read_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 207                 int whichfork);
 208 int     xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
 209                 xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 210                 int *nmap, int flags);
 211 int     xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
 212                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 213                 xfs_fsblock_t *firstblock, xfs_extlen_t total,
 214                 struct xfs_bmbt_irec *mval, int *nmap,
 215                 struct xfs_defer_ops *dfops);
 216 int     __xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 217                 xfs_fileoff_t bno, xfs_filblks_t *rlen, int flags,
 218                 xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
 219                 struct xfs_defer_ops *dfops);
 220 int     xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 221                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 222                 xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
 223                 struct xfs_defer_ops *dfops, int *done);
 224 int     xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
 225                 xfs_extnum_t num);
 226 uint    xfs_default_attroffset(struct xfs_inode *ip);
 227 int     xfs_bmap_shift_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 228                 xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
 229                 int *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
 230                 struct xfs_defer_ops *dfops, enum shift_direction direction,
 231                 int num_exts);
 232 int     xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
 233 struct xfs_bmbt_rec_host *
 234         xfs_bmap_search_extents(struct xfs_inode *ip, xfs_fileoff_t bno,
 235                 int fork, int *eofp, xfs_extnum_t *lastxp,
 236                 struct xfs_bmbt_irec *gotp, struct xfs_bmbt_irec *prevp);
 237 int     xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
 238                 xfs_fileoff_t aoff, xfs_filblks_t len,
 239                 struct xfs_bmbt_irec *got, struct xfs_bmbt_irec *prev,
 240                 xfs_extnum_t *lastx, int eof);
 241
 242 struct xfs_bmbt_rec_host *
 243         xfs_bmap_search_extents(struct xfs_inode *ip, xfs_fileoff_t bno,
 244                                 int fork, int *eofp, xfs_extnum_t *lastxp,
 245                                 struct xfs_bmbt_irec *gotp,
 246                                 struct xfs_bmbt_irec *prevp);
 247
 248
 249 enum xfs_bmap_intent_type {
 250         XFS_BMAP_MAP = 1,
 251         XFS_BMAP_UNMAP,
 252 };
 253
 254 struct xfs_bmap_intent {
 255         struct list_head                        bi_list;
 256         enum xfs_bmap_intent_type               bi_type;
 257         struct xfs_inode                        *bi_owner;
 258         int                                     bi_whichfork;
 259         struct xfs_bmbt_irec                    bi_bmap;
 260 };
 261
 262 int     xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_defer_ops *dfops,
 263                 struct xfs_inode *ip, enum xfs_bmap_intent_type type,
 264                 int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock,
 265                 xfs_filblks_t blockcount, xfs_exntst_t state);
 266 int     xfs_bmap_map_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 267                 struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
 268 int     xfs_bmap_unmap_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 269                 struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
 270
 271 #endif  /* __XFS_BMAP_H__ */