fs/xfs/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  * List of extents to be free "later".
  32  * The list is kept sorted on xbf_startblock.
  33  */
  34 typedef struct xfs_bmap_free_item
  35 {
  36         xfs_fsblock_t           xbfi_startblock;/* starting fs block number */
  37         xfs_extlen_t            xbfi_blockcount;/* number of blocks in extent */
  38         struct xfs_bmap_free_item *xbfi_next;   /* link to next entry */
  39 } xfs_bmap_free_item_t;
  40
  41 /*
  42  * Header for free extent list.
  43  *
  44  * xbf_low is used by the allocator to activate the lowspace algorithm -
  45  * when free space is running low the extent allocator may choose to
  46  * allocate an extent from an AG without leaving sufficient space for
  47  * a btree split when inserting the new extent.  In this case the allocator
  48  * will enable the lowspace algorithm which is supposed to allow further
  49  * allocations (such as btree splits and newroots) to allocate from
  50  * sequential AGs.  In order to avoid locking AGs out of order the lowspace
  51  * algorithm will start searching for free space from AG 0.  If the correct
  52  * transaction reservations have been made then this algorithm will eventually
  53  * find all the space it needs.
  54  */
  55 typedef struct xfs_bmap_free
  56 {
  57         xfs_bmap_free_item_t    *xbf_first;     /* list of to-be-free extents */
  58         int                     xbf_count;      /* count of items on list */
  59         int                     xbf_low;        /* alloc in low mode */
  60 } xfs_bmap_free_t;
  61
  62 #define XFS_BMAP_MAX_NMAP       4
  63
  64 /*
  65  * Flags for xfs_bmapi_*
  66  */
  67 #define XFS_BMAPI_ENTIRE        0x001   /* return entire extent, not trimmed */
  68 #define XFS_BMAPI_METADATA      0x002   /* mapping metadata not user data */
  69 #define XFS_BMAPI_ATTRFORK      0x004   /* use attribute fork not data */
  70 #define XFS_BMAPI_PREALLOC      0x008   /* preallocation op: unwritten space */
  71 #define XFS_BMAPI_IGSTATE       0x010   /* Ignore state - */
  72                                         /* combine contig. space */
  73 #define XFS_BMAPI_CONTIG        0x020   /* must allocate only one extent */
  74 /*
  75  * unwritten extent conversion - this needs write cache flushing and no additional
  76  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
  77  * from written to unwritten, otherwise convert from unwritten to written.
  78  */
  79 #define XFS_BMAPI_CONVERT       0x040
  80
  81 #define XFS_BMAPI_FLAGS \
  82         { XFS_BMAPI_ENTIRE,     "ENTIRE" }, \
  83         { XFS_BMAPI_METADATA,   "METADATA" }, \
  84         { XFS_BMAPI_ATTRFORK,   "ATTRFORK" }, \
  85         { XFS_BMAPI_PREALLOC,   "PREALLOC" }, \
  86         { XFS_BMAPI_IGSTATE,    "IGSTATE" }, \
  87         { XFS_BMAPI_CONTIG,     "CONTIG" }, \
  88         { XFS_BMAPI_CONVERT,    "CONVERT" }
  89
  90
  91 static inline int xfs_bmapi_aflag(int w)
  92 {
  93         return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
  94 }
  95
  96 /*
  97  * Special values for xfs_bmbt_irec_t br_startblock field.
  98  */
  99 #define DELAYSTARTBLOCK         ((xfs_fsblock_t)-1LL)
 100 #define HOLESTARTBLOCK          ((xfs_fsblock_t)-2LL)
 101
 102 static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
 103 {
 104         ((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
 105                 (flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
 106 }
 107
 108 /*
 109  * Argument structure for xfs_bmap_alloc.
 110  */
 111 typedef struct xfs_bmalloca {
 112         xfs_fsblock_t           *firstblock; /* i/o first block allocated */
 113         struct xfs_bmap_free    *flist; /* bmap freelist */
 114         struct xfs_trans        *tp;    /* transaction pointer */
 115         struct xfs_inode        *ip;    /* incore inode pointer */
 116         struct xfs_bmbt_irec    prev;   /* extent before the new one */
 117         struct xfs_bmbt_irec    got;    /* extent after, or delayed */
 118
 119         xfs_fileoff_t           offset; /* offset in file filling in */
 120         xfs_extlen_t            length; /* i/o length asked/allocated */
 121         xfs_fsblock_t           blkno;  /* starting block of new extent */
 122
 123         struct xfs_btree_cur    *cur;   /* btree cursor */
 124         xfs_extnum_t            idx;    /* current extent index */
 125         int                     nallocs;/* number of extents alloc'd */
 126         int                     logflags;/* flags for transaction logging */
 127
 128         xfs_extlen_t            total;  /* total blocks needed for xaction */
 129         xfs_extlen_t            minlen; /* minimum allocation size (blocks) */
 130         xfs_extlen_t            minleft; /* amount must be left after alloc */
 131         char                    eof;    /* set if allocating past last extent */
 132         char                    wasdel; /* replacing a delayed allocation */
 133         char                    userdata;/* set if is user data */
 134         char                    aeof;   /* allocated space at eof */
 135         char                    conv;   /* overwriting unwritten extents */
 136 } xfs_bmalloca_t;
 137
 138 /*
 139  * Flags for xfs_bmap_add_extent*.
 140  */
 141 #define BMAP_LEFT_CONTIG        (1 << 0)
 142 #define BMAP_RIGHT_CONTIG       (1 << 1)
 143 #define BMAP_LEFT_FILLING       (1 << 2)
 144 #define BMAP_RIGHT_FILLING      (1 << 3)
 145 #define BMAP_LEFT_DELAY         (1 << 4)
 146 #define BMAP_RIGHT_DELAY        (1 << 5)
 147 #define BMAP_LEFT_VALID         (1 << 6)
 148 #define BMAP_RIGHT_VALID        (1 << 7)
 149 #define BMAP_ATTRFORK           (1 << 8)
 150
 151 #define XFS_BMAP_EXT_FLAGS \
 152         { BMAP_LEFT_CONTIG,     "LC" }, \
 153         { BMAP_RIGHT_CONTIG,    "RC" }, \
 154         { BMAP_LEFT_FILLING,    "LF" }, \
 155         { BMAP_RIGHT_FILLING,   "RF" }, \
 156         { BMAP_ATTRFORK,        "ATTR" }
 157
 158 #if defined(__KERNEL) && defined(DEBUG)
 159 void    xfs_bmap_trace_exlist(struct xfs_inode *ip, xfs_extnum_t cnt,
 160                 int whichfork, unsigned long caller_ip);
 161 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)   \
 162         xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
 163 #else
 164 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)
 165 #endif
 166
 167 int     xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
 168 void    xfs_bmap_add_free(xfs_fsblock_t bno, xfs_filblks_t len,
 169                 struct xfs_bmap_free *flist, struct xfs_mount *mp);
 170 void    xfs_bmap_cancel(struct xfs_bmap_free *flist);
 171 void    xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
 172 int     xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
 173                 xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
 174 int     xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
 175                 xfs_fileoff_t *last_block, int whichfork);
 176 int     xfs_bmap_last_offset(struct xfs_trans *tp, struct xfs_inode *ip,
 177                 xfs_fileoff_t *unused, int whichfork);
 178 int     xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
 179 int     xfs_bmap_read_extents(struct xfs_trans *tp, struct xfs_inode *ip,
 180                 int whichfork);
 181 int     xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
 182                 xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 183                 int *nmap, int flags);
 184 int     xfs_bmapi_delay(struct xfs_inode *ip, xfs_fileoff_t bno,
 185                 xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 186                 int *nmap, int flags);
 187 int     xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
 188                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 189                 xfs_fsblock_t *firstblock, xfs_extlen_t total,
 190                 struct xfs_bmbt_irec *mval, int *nmap,
 191                 struct xfs_bmap_free *flist);
 192 int     xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
 193                 xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 194                 xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
 195                 struct xfs_bmap_free *flist, int *done);
 196 int     xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
 197                 xfs_extnum_t num);
 198 uint    xfs_default_attroffset(struct xfs_inode *ip);
 199
 200 #ifdef __KERNEL__
 201 /* bmap to userspace formatter - copy to user & advance pointer */
 202 typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *, int *);
 203
 204 int     xfs_bmap_finish(struct xfs_trans **tp, struct xfs_bmap_free *flist,
 205                 int *committed);
 206 int     xfs_getbmap(struct xfs_inode *ip, struct getbmapx *bmv,
 207                 xfs_bmap_format_t formatter, void *arg);
 208 int     xfs_bmap_eof(struct xfs_inode *ip, xfs_fileoff_t endoff,
 209                 int whichfork, int *eof);
 210 int     xfs_bmap_count_blocks(struct xfs_trans *tp, struct xfs_inode *ip,
 211                 int whichfork, int *count);
 212 int     xfs_bmap_punch_delalloc_range(struct xfs_inode *ip,
 213                 xfs_fileoff_t start_fsb, xfs_fileoff_t length);
 214 #endif  /* __KERNEL__ */
 215
 216 #endif  /* __XFS_BMAP_H__ */