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         struct xfs_iext_cursor  icur;   /* incore extent cursor */
  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         bool                    xefi_skip_discard;
  72 };
  73
  74 #define XFS_BMAP_MAX_NMAP       4
  75
  76 /*
  77  * Flags for xfs_bmapi_*
  78  */
  79 #define XFS_BMAPI_ENTIRE        0x001   /* return entire extent, not trimmed */
  80 #define XFS_BMAPI_METADATA      0x002   /* mapping metadata not user data */
  81 #define XFS_BMAPI_ATTRFORK      0x004   /* use attribute fork not data */
  82 #define XFS_BMAPI_PREALLOC      0x008   /* preallocation op: unwritten space */
  83 #define XFS_BMAPI_IGSTATE       0x010   /* Ignore state - */
  84                                         /* combine contig. space */
  85 #define XFS_BMAPI_CONTIG        0x020   /* must allocate only one extent */
  86 /*
  87  * unwritten extent conversion - this needs write cache flushing and no additional
  88  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
  89  * from written to unwritten, otherwise convert from unwritten to written.
  90  */
  91 #define XFS_BMAPI_CONVERT       0x040
  92
  93 /*
  94  * allocate zeroed extents - this requires all newly allocated user data extents
  95  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
  96  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
  97  * during the allocation range to zeroed written extents.
  98  */
  99 #define XFS_BMAPI_ZERO          0x080
 100
 101 /*
 102  * Map the inode offset to the block given in ap->firstblock.  Primarily
 103  * used for reflink.  The range must be in a hole, and this flag cannot be
 104  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
 105  *
 106  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
 107  * refcount, or freeing the blocks.
 108  */
 109 #define XFS_BMAPI_REMAP         0x100
 110
 111 /* Map something in the CoW fork. */
 112 #define XFS_BMAPI_COWFORK       0x200
 113
 114 /* Only convert delalloc space, don't allocate entirely new extents */
 115 #define XFS_BMAPI_DELALLOC      0x400
 116
 117 /* Only convert unwritten extents, don't allocate new blocks */
 118 #define XFS_BMAPI_CONVERT_ONLY  0x800
 119
 120 /* Skip online discard of freed extents */
 121 #define XFS_BMAPI_NODISCARD     0x1000
 122
 123 /* Do not update the rmap btree.  Used for reconstructing bmbt from rmapbt. */
 124 #define XFS_BMAPI_NORMAP        0x2000
 125
 126 #define XFS_BMAPI_FLAGS \
 127         { XFS_BMAPI_ENTIRE,     "ENTIRE" }, \
 128         { XFS_BMAPI_METADATA,   "METADATA" }, \
 129         { XFS_BMAPI_ATTRFORK,   "ATTRFORK" }, \
 130         { XFS_BMAPI_PREALLOC,   "PREALLOC" }, \
 131         { XFS_BMAPI_IGSTATE,    "IGSTATE" }, \
 132         { XFS_BMAPI_CONTIG,     "CONTIG" }, \
 133         { XFS_BMAPI_CONVERT,    "CONVERT" }, \
 134         { XFS_BMAPI_ZERO,       "ZERO" }, \
 135         { XFS_BMAPI_REMAP,      "REMAP" }, \
 136         { XFS_BMAPI_COWFORK,    "COWFORK" }, \
 137         { XFS_BMAPI_DELALLOC,   "DELALLOC" }, \
 138         { XFS_BMAPI_CONVERT_ONLY, "CONVERT_ONLY" }, \
 139         { XFS_BMAPI_NODISCARD,  "NODISCARD" }, \
 140         { XFS_BMAPI_NORMAP,     "NORMAP" }
 141
 142
 143 static inline int xfs_bmapi_aflag(int w)
 144 {
 145         return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
 146                (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
 147 }
 148
 149 static inline int xfs_bmapi_whichfork(int bmapi_flags)
 150 {
 151         if (bmapi_flags & XFS_BMAPI_COWFORK)
 152                 return XFS_COW_FORK;
 153         else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
 154                 return XFS_ATTR_FORK;
 155         return XFS_DATA_FORK;
 156 }
 157
 158 /*
 159  * Special values for xfs_bmbt_irec_t br_startblock field.
 160  */
 161 #define DELAYSTARTBLOCK         ((xfs_fsblock_t)-1LL)
 162 #define HOLESTARTBLOCK          ((xfs_fsblock_t)-2LL)
 163
 164 /*
 165  * Flags for xfs_bmap_add_extent*.
 166  */
 167 #define BMAP_LEFT_CONTIG        (1 << 0)
 168 #define BMAP_RIGHT_CONTIG       (1 << 1)
 169 #define BMAP_LEFT_FILLING       (1 << 2)
 170 #define BMAP_RIGHT_FILLING      (1 << 3)
 171 #define BMAP_LEFT_DELAY         (1 << 4)
 172 #define BMAP_RIGHT_DELAY        (1 << 5)
 173 #define BMAP_LEFT_VALID         (1 << 6)
 174 #define BMAP_RIGHT_VALID        (1 << 7)
 175 #define BMAP_ATTRFORK           (1 << 8)
 176 #define BMAP_COWFORK            (1 << 9)
 177
 178 #define XFS_BMAP_EXT_FLAGS \
 179         { BMAP_LEFT_CONTIG,     "LC" }, \
 180         { BMAP_RIGHT_CONTIG,    "RC" }, \
 181         { BMAP_LEFT_FILLING,    "LF" }, \
 182         { BMAP_RIGHT_FILLING,   "RF" }, \
 183         { BMAP_ATTRFORK,        "ATTR" }, \
 184         { BMAP_COWFORK,         "COW" }
 185
 186
 187 /*
 188  * Return true if the extent is a real, allocated extent, or false if it is  a
 189  * delayed allocation, and unwritten extent or a hole.
 190  */
 191 static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec)
 192 {
 193         return irec->br_state != XFS_EXT_UNWRITTEN &&
 194                 irec->br_startblock != HOLESTARTBLOCK &&
 195                 irec->br_startblock != DELAYSTARTBLOCK &&
 196                 !isnullstartblock(irec->br_startblock);
 197 }
 198
 199 void    xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
 200                 xfs_filblks_t len);
 201 void    xfs_trim_extent_eof(struct xfs_bmbt_irec *, struct xfs_inode *);
 202 int     xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
 203 void    xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
 204 void    __xfs_bmap_add_free(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 205                           xfs_fsblock_t bno, xfs_filblks_t len,
 206                           struct xfs_owner_info *oinfo, bool skip_discard);
 207 void    xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
 208 int     xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
 209                 xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
 210 int     xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
 211                 xfs_fileoff_t *last_block, int whichfork);
 212 int     xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
 213                 int whichfork);
 214 int     xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
 215 int     xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
 216                 xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 217                 int *nmap, int flags);
 218 int     xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
 219                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 220                 xfs_fsblock_t *firstblock, xfs_extlen_t total,
 221                 struct xfs_bmbt_irec *mval, int *nmap,
 222                 struct xfs_defer_ops *dfops);
 223 int     __xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 224                 xfs_fileoff_t bno, xfs_filblks_t *rlen, int flags,
 225                 xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
 226                 struct xfs_defer_ops *dfops);
 227 int     xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 228                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 229                 xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
 230                 struct xfs_defer_ops *dfops, int *done);
 231 int     xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
 232                 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
 233                 struct xfs_bmbt_irec *del);
 234 void    xfs_bmap_del_extent_cow(struct xfs_inode *ip,
 235                 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
 236                 struct xfs_bmbt_irec *del);
 237 uint    xfs_default_attroffset(struct xfs_inode *ip);
 238 int     xfs_bmap_collapse_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 239                 xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
 240                 bool *done, xfs_fsblock_t *firstblock,
 241                 struct xfs_defer_ops *dfops);
 242 int     xfs_bmap_insert_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 243                 xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
 244                 bool *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
 245                 struct xfs_defer_ops *dfops);
 246 int     xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
 247 int     xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
 248                 xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
 249                 struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
 250                 int eof);
 251
 252 static inline void
 253 xfs_bmap_add_free(
 254         struct xfs_mount                *mp,
 255         struct xfs_defer_ops            *dfops,
 256         xfs_fsblock_t                   bno,
 257         xfs_filblks_t                   len,
 258         struct xfs_owner_info           *oinfo)
 259 {
 260         __xfs_bmap_add_free(mp, dfops, bno, len, oinfo, false);
 261 }
 262
 263 enum xfs_bmap_intent_type {
 264         XFS_BMAP_MAP = 1,
 265         XFS_BMAP_UNMAP,
 266 };
 267
 268 struct xfs_bmap_intent {
 269         struct list_head                        bi_list;
 270         enum xfs_bmap_intent_type               bi_type;
 271         struct xfs_inode                        *bi_owner;
 272         int                                     bi_whichfork;
 273         struct xfs_bmbt_irec                    bi_bmap;
 274 };
 275
 276 int     xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_defer_ops *dfops,
 277                 struct xfs_inode *ip, enum xfs_bmap_intent_type type,
 278                 int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock,
 279                 xfs_filblks_t *blockcount, xfs_exntst_t state);
 280 int     xfs_bmap_map_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 281                 struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
 282 int     xfs_bmap_unmap_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 283                 struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
 284
 285 static inline int xfs_bmap_fork_to_state(int whichfork)
 286 {
 287         switch (whichfork) {
 288         case XFS_ATTR_FORK:
 289                 return BMAP_ATTRFORK;
 290         case XFS_COW_FORK:
 291                 return BMAP_COWFORK;
 292         default:
 293                 return 0;
 294         }
 295 }
 296
 297 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
 298                 struct xfs_bmbt_irec *irec);
 299
 300 int     xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
 301                 xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
 302                 struct xfs_defer_ops *dfops, int flags);
 303
 304 #endif  /* __XFS_BMAP_H__ */