root/fs/xfs/libxfs/xfs_bmap.h

INCLUDED FROM

DEFINITIONS

1. xfs_bmapi_aflag
2. xfs_bmapi_whichfork
3. xfs_bmap_is_real_extent
4. xfs_bmap_add_free
5. xfs_bmap_fork_to_state

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   4  * All Rights Reserved.
   5  */
   6 #ifndef __XFS_BMAP_H__
   7 #define __XFS_BMAP_H__
   8 
   9 struct getbmap;
  10 struct xfs_bmbt_irec;
  11 struct xfs_ifork;
  12 struct xfs_inode;
  13 struct xfs_mount;
  14 struct xfs_trans;
  15 
  16 extern kmem_zone_t      *xfs_bmap_free_item_zone;
  17 
  18 /*
  19  * Argument structure for xfs_bmap_alloc.
  20  */
  21 struct xfs_bmalloca {
  22         struct xfs_trans        *tp;    /* transaction pointer */
  23         struct xfs_inode        *ip;    /* incore inode pointer */
  24         struct xfs_bmbt_irec    prev;   /* extent before the new one */
  25         struct xfs_bmbt_irec    got;    /* extent after, or delayed */
  26 
  27         xfs_fileoff_t           offset; /* offset in file filling in */
  28         xfs_extlen_t            length; /* i/o length asked/allocated */
  29         xfs_fsblock_t           blkno;  /* starting block of new extent */
  30 
  31         struct xfs_btree_cur    *cur;   /* btree cursor */
  32         struct xfs_iext_cursor  icur;   /* incore extent cursor */
  33         int                     nallocs;/* number of extents alloc'd */
  34         int                     logflags;/* flags for transaction logging */
  35 
  36         xfs_extlen_t            total;  /* total blocks needed for xaction */
  37         xfs_extlen_t            minlen; /* minimum allocation size (blocks) */
  38         xfs_extlen_t            minleft; /* amount must be left after alloc */
  39         bool                    eof;    /* set if allocating past last extent */
  40         bool                    wasdel; /* replacing a delayed allocation */
  41         bool                    aeof;   /* allocated space at eof */
  42         bool                    conv;   /* overwriting unwritten extents */
  43         int                     datatype;/* data type being allocated */
  44         int                     flags;
  45 };
  46 
  47 /*
  48  * List of extents to be free "later".
  49  * The list is kept sorted on xbf_startblock.
  50  */
  51 struct xfs_extent_free_item
  52 {
  53         xfs_fsblock_t           xefi_startblock;/* starting fs block number */
  54         xfs_extlen_t            xefi_blockcount;/* number of blocks in extent */
  55         struct list_head        xefi_list;
  56         struct xfs_owner_info   xefi_oinfo;     /* extent owner */
  57         bool                    xefi_skip_discard;
  58 };
  59 
  60 #define XFS_BMAP_MAX_NMAP       4
  61 
  62 /*
  63  * Flags for xfs_bmapi_*
  64  */
  65 #define XFS_BMAPI_ENTIRE        0x001   /* return entire extent, not trimmed */
  66 #define XFS_BMAPI_METADATA      0x002   /* mapping metadata not user data */
  67 #define XFS_BMAPI_ATTRFORK      0x004   /* use attribute fork not data */
  68 #define XFS_BMAPI_PREALLOC      0x008   /* preallocation op: unwritten space */
  69 #define XFS_BMAPI_CONTIG        0x020   /* must allocate only one extent */
  70 /*
  71  * unwritten extent conversion - this needs write cache flushing and no additional
  72  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
  73  * from written to unwritten, otherwise convert from unwritten to written.
  74  */
  75 #define XFS_BMAPI_CONVERT       0x040
  76 
  77 /*
  78  * allocate zeroed extents - this requires all newly allocated user data extents
  79  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
  80  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
  81  * during the allocation range to zeroed written extents.
  82  */
  83 #define XFS_BMAPI_ZERO          0x080
  84 
  85 /*
  86  * Map the inode offset to the block given in ap->firstblock.  Primarily
  87  * used for reflink.  The range must be in a hole, and this flag cannot be
  88  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
  89  *
  90  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
  91  * refcount, or freeing the blocks.
  92  */
  93 #define XFS_BMAPI_REMAP         0x100
  94 
  95 /* Map something in the CoW fork. */
  96 #define XFS_BMAPI_COWFORK       0x200
  97 
  98 /* Skip online discard of freed extents */
  99 #define XFS_BMAPI_NODISCARD     0x1000
 100 
 101 /* Do not update the rmap btree.  Used for reconstructing bmbt from rmapbt. */
 102 #define XFS_BMAPI_NORMAP        0x2000
 103 
 104 #define XFS_BMAPI_FLAGS \
 105         { XFS_BMAPI_ENTIRE,     "ENTIRE" }, \
 106         { XFS_BMAPI_METADATA,   "METADATA" }, \
 107         { XFS_BMAPI_ATTRFORK,   "ATTRFORK" }, \
 108         { XFS_BMAPI_PREALLOC,   "PREALLOC" }, \
 109         { XFS_BMAPI_CONTIG,     "CONTIG" }, \
 110         { XFS_BMAPI_CONVERT,    "CONVERT" }, \
 111         { XFS_BMAPI_ZERO,       "ZERO" }, \
 112         { XFS_BMAPI_REMAP,      "REMAP" }, \
 113         { XFS_BMAPI_COWFORK,    "COWFORK" }, \
 114         { XFS_BMAPI_NODISCARD,  "NODISCARD" }, \
 115         { XFS_BMAPI_NORMAP,     "NORMAP" }
 116 
 117 
 118 static inline int xfs_bmapi_aflag(int w)
 119 {
 120         return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
 121                (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
 122 }
 123 
 124 static inline int xfs_bmapi_whichfork(int bmapi_flags)
 125 {
 126         if (bmapi_flags & XFS_BMAPI_COWFORK)
 127                 return XFS_COW_FORK;
 128         else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
 129                 return XFS_ATTR_FORK;
 130         return XFS_DATA_FORK;
 131 }
 132 
 133 /*
 134  * Special values for xfs_bmbt_irec_t br_startblock field.
 135  */
 136 #define DELAYSTARTBLOCK         ((xfs_fsblock_t)-1LL)
 137 #define HOLESTARTBLOCK          ((xfs_fsblock_t)-2LL)
 138 
 139 /*
 140  * Flags for xfs_bmap_add_extent*.
 141  */
 142 #define BMAP_LEFT_CONTIG        (1 << 0)
 143 #define BMAP_RIGHT_CONTIG       (1 << 1)
 144 #define BMAP_LEFT_FILLING       (1 << 2)
 145 #define BMAP_RIGHT_FILLING      (1 << 3)
 146 #define BMAP_LEFT_DELAY         (1 << 4)
 147 #define BMAP_RIGHT_DELAY        (1 << 5)
 148 #define BMAP_LEFT_VALID         (1 << 6)
 149 #define BMAP_RIGHT_VALID        (1 << 7)
 150 #define BMAP_ATTRFORK           (1 << 8)
 151 #define BMAP_COWFORK            (1 << 9)
 152 
 153 #define XFS_BMAP_EXT_FLAGS \
 154         { BMAP_LEFT_CONTIG,     "LC" }, \
 155         { BMAP_RIGHT_CONTIG,    "RC" }, \
 156         { BMAP_LEFT_FILLING,    "LF" }, \
 157         { BMAP_RIGHT_FILLING,   "RF" }, \
 158         { BMAP_ATTRFORK,        "ATTR" }, \
 159         { BMAP_COWFORK,         "COW" }
 160 
 161 
 162 /*
 163  * Return true if the extent is a real, allocated extent, or false if it is  a
 164  * delayed allocation, and unwritten extent or a hole.
 165  */
 166 static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec)
 167 {
 168         return irec->br_state != XFS_EXT_UNWRITTEN &&
 169                 irec->br_startblock != HOLESTARTBLOCK &&
 170                 irec->br_startblock != DELAYSTARTBLOCK &&
 171                 !isnullstartblock(irec->br_startblock);
 172 }
 173 
 174 /*
 175  * Check the mapping for obviously garbage allocations that could trash the
 176  * filesystem immediately.
 177  */
 178 #define xfs_valid_startblock(ip, startblock) \
 179         ((startblock) != 0 || XFS_IS_REALTIME_INODE(ip))
 180 
 181 void    xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
 182                 xfs_filblks_t len);
 183 int     xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
 184 int     xfs_bmap_set_attrforkoff(struct xfs_inode *ip, int size, int *version);
 185 void    xfs_bmap_local_to_extents_empty(struct xfs_trans *tp,
 186                 struct xfs_inode *ip, int whichfork);
 187 void    __xfs_bmap_add_free(struct xfs_trans *tp, xfs_fsblock_t bno,
 188                 xfs_filblks_t len, const struct xfs_owner_info *oinfo,
 189                 bool skip_discard);
 190 void    xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
 191 int     xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
 192                 xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
 193 int     xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
 194                 xfs_fileoff_t *last_block, int whichfork);
 195 int     xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
 196                 int whichfork);
 197 int     xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
 198 int     xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
 199                 xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 200                 int *nmap, int flags);
 201 int     xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
 202                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 203                 xfs_extlen_t total, struct xfs_bmbt_irec *mval, int *nmap);
 204 int     __xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 205                 xfs_fileoff_t bno, xfs_filblks_t *rlen, int flags,
 206                 xfs_extnum_t nexts);
 207 int     xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 208                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 209                 xfs_extnum_t nexts, int *done);
 210 int     xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
 211                 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
 212                 struct xfs_bmbt_irec *del);
 213 void    xfs_bmap_del_extent_cow(struct xfs_inode *ip,
 214                 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
 215                 struct xfs_bmbt_irec *del);
 216 uint    xfs_default_attroffset(struct xfs_inode *ip);
 217 int     xfs_bmap_collapse_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 218                 xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
 219                 bool *done);
 220 int     xfs_bmap_can_insert_extents(struct xfs_inode *ip, xfs_fileoff_t off,
 221                 xfs_fileoff_t shift);
 222 int     xfs_bmap_insert_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 223                 xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
 224                 bool *done, xfs_fileoff_t stop_fsb);
 225 int     xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
 226 int     xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
 227                 xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
 228                 struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
 229                 int eof);
 230 int     xfs_bmapi_convert_delalloc(struct xfs_inode *ip, int whichfork,
 231                 xfs_fileoff_t offset_fsb, struct xfs_bmbt_irec *imap,
 232                 unsigned int *seq);
 233 int     xfs_bmap_add_extent_unwritten_real(struct xfs_trans *tp,
 234                 struct xfs_inode *ip, int whichfork,
 235                 struct xfs_iext_cursor *icur, struct xfs_btree_cur **curp,
 236                 struct xfs_bmbt_irec *new, int *logflagsp);
 237 
 238 static inline void
 239 xfs_bmap_add_free(
 240         struct xfs_trans                *tp,
 241         xfs_fsblock_t                   bno,
 242         xfs_filblks_t                   len,
 243         const struct xfs_owner_info     *oinfo)
 244 {
 245         __xfs_bmap_add_free(tp, bno, len, oinfo, false);
 246 }
 247 
 248 enum xfs_bmap_intent_type {
 249         XFS_BMAP_MAP = 1,
 250         XFS_BMAP_UNMAP,
 251 };
 252 
 253 struct xfs_bmap_intent {
 254         struct list_head                        bi_list;
 255         enum xfs_bmap_intent_type               bi_type;
 256         struct xfs_inode                        *bi_owner;
 257         int                                     bi_whichfork;
 258         struct xfs_bmbt_irec                    bi_bmap;
 259 };
 260 
 261 int     xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_inode *ip,
 262                 enum xfs_bmap_intent_type type, int whichfork,
 263                 xfs_fileoff_t startoff, xfs_fsblock_t startblock,
 264                 xfs_filblks_t *blockcount, xfs_exntst_t state);
 265 void    xfs_bmap_map_extent(struct xfs_trans *tp, struct xfs_inode *ip,
 266                 struct xfs_bmbt_irec *imap);
 267 void    xfs_bmap_unmap_extent(struct xfs_trans *tp, struct xfs_inode *ip,
 268                 struct xfs_bmbt_irec *imap);
 269 
 270 static inline int xfs_bmap_fork_to_state(int whichfork)
 271 {
 272         switch (whichfork) {
 273         case XFS_ATTR_FORK:
 274                 return BMAP_ATTRFORK;
 275         case XFS_COW_FORK:
 276                 return BMAP_COWFORK;
 277         default:
 278                 return 0;
 279         }
 280 }
 281 
 282 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
 283                 struct xfs_bmbt_irec *irec);
 284 
 285 int     xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
 286                 xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
 287                 int flags);
 288 
 289 #endif  /* __XFS_BMAP_H__ */