fs/xfs/xfs_buf_item.h

   1 /*
   2  * Copyright (c) 2000-2001,2005 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_BUF_ITEM_H__
  19 #define __XFS_BUF_ITEM_H__
  20
  21 extern kmem_zone_t      *xfs_buf_item_zone;
  22
  23 /*
  24  * This flag indicates that the buffer contains on disk inodes
  25  * and requires special recovery handling.
  26  */
  27 #define XFS_BLF_INODE_BUF       (1<<0)
  28 /*
  29  * This flag indicates that the buffer should not be replayed
  30  * during recovery because its blocks are being freed.
  31  */
  32 #define XFS_BLF_CANCEL          (1<<1)
  33
  34 /*
  35  * This flag indicates that the buffer contains on disk
  36  * user or group dquots and may require special recovery handling.
  37  */
  38 #define XFS_BLF_UDQUOT_BUF      (1<<2)
  39 #define XFS_BLF_PDQUOT_BUF      (1<<3)
  40 #define XFS_BLF_GDQUOT_BUF      (1<<4)
  41
  42 #define XFS_BLF_CHUNK           128
  43 #define XFS_BLF_SHIFT           7
  44 #define BIT_TO_WORD_SHIFT       5
  45 #define NBWORD                  (NBBY * sizeof(unsigned int))
  46
  47 /*
  48  * This is the structure used to lay out a buf log item in the
  49  * log.  The data map describes which 128 byte chunks of the buffer
  50  * have been logged.
  51  */
  52 #define XFS_BLF_DATAMAP_SIZE    ((XFS_MAX_BLOCKSIZE / XFS_BLF_CHUNK) / NBWORD)
  53
  54 typedef struct xfs_buf_log_format {
  55         unsigned short  blf_type;       /* buf log item type indicator */
  56         unsigned short  blf_size;       /* size of this item */
  57         ushort          blf_flags;      /* misc state */
  58         ushort          blf_len;        /* number of blocks in this buf */
  59         __int64_t       blf_blkno;      /* starting blkno of this buf */
  60         unsigned int    blf_map_size;   /* used size of data bitmap in words */
  61         unsigned int    blf_data_map[XFS_BLF_DATAMAP_SIZE]; /* dirty bitmap */
  62 } xfs_buf_log_format_t;
  63
  64 /*
  65  * All buffers now need to tell recovery where the magic number
  66  * is so that it can verify and calculate the CRCs on the buffer correctly
  67  * once the changes have been replayed into the buffer.
  68  *
  69  * The type value is held in the upper 5 bits of the blf_flags field, which is
  70  * an unsigned 16 bit field. Hence we need to shift it 11 bits up and down.
  71  */
  72 #define XFS_BLFT_BITS   5
  73 #define XFS_BLFT_SHIFT  11
  74 #define XFS_BLFT_MASK   (((1 << XFS_BLFT_BITS) - 1) << XFS_BLFT_SHIFT)
  75
  76 enum xfs_blft {
  77         XFS_BLFT_UNKNOWN_BUF = 0,
  78         XFS_BLFT_UDQUOT_BUF,
  79         XFS_BLFT_PDQUOT_BUF,
  80         XFS_BLFT_GDQUOT_BUF,
  81         XFS_BLFT_BTREE_BUF,
  82         XFS_BLFT_AGF_BUF,
  83         XFS_BLFT_AGFL_BUF,
  84         XFS_BLFT_AGI_BUF,
  85         XFS_BLFT_DINO_BUF,
  86         XFS_BLFT_SYMLINK_BUF,
  87         XFS_BLFT_DIR_BLOCK_BUF,
  88         XFS_BLFT_DIR_DATA_BUF,
  89         XFS_BLFT_DIR_FREE_BUF,
  90         XFS_BLFT_DIR_LEAF1_BUF,
  91         XFS_BLFT_DIR_LEAFN_BUF,
  92         XFS_BLFT_DA_NODE_BUF,
  93         XFS_BLFT_ATTR_LEAF_BUF,
  94         XFS_BLFT_ATTR_RMT_BUF,
  95         XFS_BLFT_SB_BUF,
  96         XFS_BLFT_MAX_BUF = (1 << XFS_BLFT_BITS),
  97 };
  98
  99 static inline void
 100 xfs_blft_to_flags(struct xfs_buf_log_format *blf, enum xfs_blft type)
 101 {
 102         ASSERT(type > XFS_BLFT_UNKNOWN_BUF && type < XFS_BLFT_MAX_BUF);
 103         blf->blf_flags &= ~XFS_BLFT_MASK;
 104         blf->blf_flags |= ((type << XFS_BLFT_SHIFT) & XFS_BLFT_MASK);
 105 }
 106
 107 static inline __uint16_t
 108 xfs_blft_from_flags(struct xfs_buf_log_format *blf)
 109 {
 110         return (blf->blf_flags & XFS_BLFT_MASK) >> XFS_BLFT_SHIFT;
 111 }
 112
 113 /*
 114  * buf log item flags
 115  */
 116 #define XFS_BLI_HOLD            0x01
 117 #define XFS_BLI_DIRTY           0x02
 118 #define XFS_BLI_STALE           0x04
 119 #define XFS_BLI_LOGGED          0x08
 120 #define XFS_BLI_INODE_ALLOC_BUF 0x10
 121 #define XFS_BLI_STALE_INODE     0x20
 122 #define XFS_BLI_INODE_BUF       0x40
 123 #define XFS_BLI_ORDERED         0x80
 124
 125 #define XFS_BLI_FLAGS \
 126         { XFS_BLI_HOLD,         "HOLD" }, \
 127         { XFS_BLI_DIRTY,        "DIRTY" }, \
 128         { XFS_BLI_STALE,        "STALE" }, \
 129         { XFS_BLI_LOGGED,       "LOGGED" }, \
 130         { XFS_BLI_INODE_ALLOC_BUF, "INODE_ALLOC" }, \
 131         { XFS_BLI_STALE_INODE,  "STALE_INODE" }, \
 132         { XFS_BLI_INODE_BUF,    "INODE_BUF" }, \
 133         { XFS_BLI_ORDERED,      "ORDERED" }
 134
 135
 136 #ifdef __KERNEL__
 137
 138 struct xfs_buf;
 139 struct xfs_mount;
 140 struct xfs_buf_log_item;
 141
 142 /*
 143  * This is the in core log item structure used to track information
 144  * needed to log buffers.  It tracks how many times the lock has been
 145  * locked, and which 128 byte chunks of the buffer are dirty.
 146  */
 147 typedef struct xfs_buf_log_item {
 148         xfs_log_item_t          bli_item;       /* common item structure */
 149         struct xfs_buf          *bli_buf;       /* real buffer pointer */
 150         unsigned int            bli_flags;      /* misc flags */
 151         unsigned int            bli_recur;      /* lock recursion count */
 152         atomic_t                bli_refcount;   /* cnt of tp refs */
 153         int                     bli_format_count;       /* count of headers */
 154         struct xfs_buf_log_format *bli_formats; /* array of in-log header ptrs */
 155         struct xfs_buf_log_format __bli_format; /* embedded in-log header */
 156 } xfs_buf_log_item_t;
 157
 158 void    xfs_buf_item_init(struct xfs_buf *, struct xfs_mount *);
 159 void    xfs_buf_item_relse(struct xfs_buf *);
 160 void    xfs_buf_item_log(xfs_buf_log_item_t *, uint, uint);
 161 uint    xfs_buf_item_dirty(xfs_buf_log_item_t *);
 162 void    xfs_buf_attach_iodone(struct xfs_buf *,
 163                               void(*)(struct xfs_buf *, xfs_log_item_t *),
 164                               xfs_log_item_t *);
 165 void    xfs_buf_iodone_callbacks(struct xfs_buf *);
 166 void    xfs_buf_iodone(struct xfs_buf *, struct xfs_log_item *);
 167
 168 void    xfs_trans_buf_set_type(struct xfs_trans *, struct xfs_buf *,
 169                                enum xfs_blft);
 170 void    xfs_trans_buf_copy_type(struct xfs_buf *dst_bp, struct xfs_buf *src_bp);
 171
 172 #endif  /* __KERNEL__ */
 173
 174 #endif  /* __XFS_BUF_ITEM_H__ */