1 files changed, 208 insertions, 184 deletions

diff --git a/fs/xfs/xfs_btree.h b/fs/xfs/xfs_btree.h
index 1f528a2a3754..789fffdf8b2f 100644
--- a/fs/xfs/xfs_btree.h
+++ b/fs/xfs/xfs_btree.h
@@ -39,39 +39,19 @@ extern kmem_zone_t	*xfs_btree_cur_zone;
 #define XFS_BTNUM_INO   ((xfs_btnum_t)XFS_BTNUM_INOi)
 
 /*
- * Short form header: space allocation btrees.
- */
-typedef struct xfs_btree_sblock {
-        __be32          bb_magic;       /* magic number for block type */
-        __be16          bb_level;       /* 0 is a leaf */
-        __be16          bb_numrecs;     /* current # of data records */
-        __be32          bb_leftsib;     /* left sibling block or NULLAGBLOCK */
-        __be32          bb_rightsib;    /* right sibling block or NULLAGBLOCK */
-} xfs_btree_sblock_t;
-
-/*
- * Long form header: bmap btrees.
- */
-typedef struct xfs_btree_lblock {
-        __be32          bb_magic;       /* magic number for block type */
-        __be16          bb_level;       /* 0 is a leaf */
-        __be16          bb_numrecs;     /* current # of data records */
-        __be64          bb_leftsib;     /* left sibling block or NULLDFSBNO */
-        __be64          bb_rightsib;    /* right sibling block or NULLDFSBNO */
-} xfs_btree_lblock_t;
-
-/*
- * Combined header and structure, used by common code.
+ * Generic btree header.
+ *
+ * This is a comination of the actual format used on disk for short and long
+ * format btrees.  The first three fields are shared by both format, but
+ * the pointers are different and should be used with care.
+ *
+ * To get the size of the actual short or long form headers please use
+ * the size macros below.  Never use sizeof(xfs_btree_block).
  */
-typedef struct xfs_btree_hdr
-{
+struct xfs_btree_block {
         __be32          bb_magic;       /* magic number for block type */
         __be16          bb_level;       /* 0 is a leaf */
         __be16          bb_numrecs;     /* current # of data records */
-} xfs_btree_hdr_t;
-
-typedef struct xfs_btree_block {
-        xfs_btree_hdr_t bb_h;           /* header */
         union {
                 struct {
                         __be32          bb_leftsib;
@@ -82,7 +62,36 @@ typedef struct xfs_btree_block {
                         __be64          bb_rightsib;
                 } l;                    /* long form pointers */
         } bb_u;                         /* rest */
-} xfs_btree_block_t;
+};
+
+#define XFS_BTREE_SBLOCK_LEN    16      /* size of a short form block */
+#define XFS_BTREE_LBLOCK_LEN    24      /* size of a long form block */
+
+
+/*
+ * Generic key, ptr and record wrapper structures.
+ *
+ * These are disk format structures, and are converted where necessary
+ * by the btree specific code that needs to interpret them.
+ */
+union xfs_btree_ptr {
+        __be32                  s;      /* short form ptr */
+        __be64                  l;      /* long form ptr */
+};
+
+union xfs_btree_key {
+        xfs_bmbt_key_t          bmbt;
+        xfs_bmdr_key_t          bmbr;   /* bmbt root block */
+        xfs_alloc_key_t         alloc;
+        xfs_inobt_key_t         inobt;
+};
+
+union xfs_btree_rec {
+        xfs_bmbt_rec_t          bmbt;
+        xfs_bmdr_rec_t          bmbr;   /* bmbt root block */
+        xfs_alloc_rec_t         alloc;
+        xfs_inobt_rec_t         inobt;
+};
 
 /*
  * For logging record fields.
@@ -96,46 +105,131 @@ typedef struct xfs_btree_block {
 #define XFS_BB_ALL_BITS         ((1 << XFS_BB_NUM_BITS) - 1)
 
 /*
- * Boolean to select which form of xfs_btree_block_t.bb_u to use.
- */
-#define XFS_BTREE_LONG_PTRS(btnum)      ((btnum) == XFS_BTNUM_BMAP)
-
-/*
  * Magic numbers for btree blocks.
  */
 extern const __uint32_t xfs_magics[];
 
 /*
- * Maximum and minimum records in a btree block.
- * Given block size, type prefix, and leaf flag (0 or 1).
- * The divisor below is equivalent to lf ? (e1) : (e2) but that produces
- * compiler warnings.
- */
-#define XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf)       \
-        ((int)(((bsz) - (uint)sizeof(t ## _block_t)) / \
-         (((lf) * (uint)sizeof(t ## _rec_t)) + \
-          ((1 - (lf)) * \
-           ((uint)sizeof(t ## _key_t) + (uint)sizeof(t ## _ptr_t))))))
-#define XFS_BTREE_BLOCK_MINRECS(bsz,t,lf)       \
-        (XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf) / 2)
-
-/*
- * Record, key, and pointer address calculation macros.
- * Given block size, type prefix, block pointer, and index of requested entry
- * (first entry numbered 1).
- */
-#define XFS_BTREE_REC_ADDR(t,bb,i)      \
-        ((t ## _rec_t *)((char *)(bb) + sizeof(t ## _block_t) + \
-         ((i) - 1) * sizeof(t ## _rec_t)))
-#define XFS_BTREE_KEY_ADDR(t,bb,i)      \
-        ((t ## _key_t *)((char *)(bb) + sizeof(t ## _block_t) + \
-         ((i) - 1) * sizeof(t ## _key_t)))
-#define XFS_BTREE_PTR_ADDR(t,bb,i,mxr)  \
-        ((t ## _ptr_t *)((char *)(bb) + sizeof(t ## _block_t) + \
-         (mxr) * sizeof(t ## _key_t) + ((i) - 1) * sizeof(t ## _ptr_t)))
+ * Generic stats interface
+ */
+#define __XFS_BTREE_STATS_INC(type, stat) \
+        XFS_STATS_INC(xs_ ## type ## _2_ ## stat)
+#define XFS_BTREE_STATS_INC(cur, stat)  \
+do {    \
+        switch (cur->bc_btnum) {  \
+        case XFS_BTNUM_BNO: __XFS_BTREE_STATS_INC(abtb, stat); break;   \
+        case XFS_BTNUM_CNT: __XFS_BTREE_STATS_INC(abtc, stat); break;   \
+        case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_INC(bmbt, stat); break;  \
+        case XFS_BTNUM_INO: __XFS_BTREE_STATS_INC(ibt, stat); break;    \
+        case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break;       \
+        }       \
+} while (0)
+
+#define __XFS_BTREE_STATS_ADD(type, stat, val) \
+        XFS_STATS_ADD(xs_ ## type ## _2_ ## stat, val)
+#define XFS_BTREE_STATS_ADD(cur, stat, val)  \
+do {    \
+        switch (cur->bc_btnum) {  \
+        case XFS_BTNUM_BNO: __XFS_BTREE_STATS_ADD(abtb, stat, val); break; \
+        case XFS_BTNUM_CNT: __XFS_BTREE_STATS_ADD(abtc, stat, val); break; \
+        case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_ADD(bmbt, stat, val); break; \
+        case XFS_BTNUM_INO: __XFS_BTREE_STATS_ADD(ibt, stat, val); break; \
+        case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break;       \
+        }       \
+} while (0)
 
 #define XFS_BTREE_MAXLEVELS     8       /* max of all btrees */
 
+struct xfs_btree_ops {
+        /* size of the key and record structures */
+        size_t  key_len;
+        size_t  rec_len;
+
+        /* cursor operations */
+        struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
+        void    (*update_cursor)(struct xfs_btree_cur *src,
+                                 struct xfs_btree_cur *dst);
+
+        /* update btree root pointer */
+        void    (*set_root)(struct xfs_btree_cur *cur,
+                                union xfs_btree_ptr *nptr, int level_change);
+        int     (*kill_root)(struct xfs_btree_cur *cur, struct xfs_buf *bp,
+                                int level, union xfs_btree_ptr *newroot);
+
+        /* block allocation / freeing */
+        int     (*alloc_block)(struct xfs_btree_cur *cur,
+                               union xfs_btree_ptr *start_bno,
+                               union xfs_btree_ptr *new_bno,
+                               int length, int *stat);
+        int     (*free_block)(struct xfs_btree_cur *cur, struct xfs_buf *bp);
+
+        /* update last record information */
+        void    (*update_lastrec)(struct xfs_btree_cur *cur,
+                                  struct xfs_btree_block *block,
+                                  union xfs_btree_rec *rec,
+                                  int ptr, int reason);
+
+        /* records in block/level */
+        int     (*get_minrecs)(struct xfs_btree_cur *cur, int level);
+        int     (*get_maxrecs)(struct xfs_btree_cur *cur, int level);
+
+        /* records on disk.  Matter for the root in inode case. */
+        int     (*get_dmaxrecs)(struct xfs_btree_cur *cur, int level);
+
+        /* init values of btree structures */
+        void    (*init_key_from_rec)(union xfs_btree_key *key,
+                                     union xfs_btree_rec *rec);
+        void    (*init_rec_from_key)(union xfs_btree_key *key,
+                                     union xfs_btree_rec *rec);
+        void    (*init_rec_from_cur)(struct xfs_btree_cur *cur,
+                                     union xfs_btree_rec *rec);
+        void    (*init_ptr_from_cur)(struct xfs_btree_cur *cur,
+                                     union xfs_btree_ptr *ptr);
+
+        /* difference between key value and cursor value */
+        __int64_t (*key_diff)(struct xfs_btree_cur *cur,
+                              union xfs_btree_key *key);
+
+#ifdef DEBUG
+        /* check that k1 is lower than k2 */
+        int     (*keys_inorder)(struct xfs_btree_cur *cur,
+                                union xfs_btree_key *k1,
+                                union xfs_btree_key *k2);
+
+        /* check that r1 is lower than r2 */
+        int     (*recs_inorder)(struct xfs_btree_cur *cur,
+                                union xfs_btree_rec *r1,
+                                union xfs_btree_rec *r2);
+#endif
+
+        /* btree tracing */
+#ifdef XFS_BTREE_TRACE
+        void            (*trace_enter)(struct xfs_btree_cur *, const char *,
+                                       char *, int, int, __psunsigned_t,
+                                       __psunsigned_t, __psunsigned_t,
+                                       __psunsigned_t, __psunsigned_t,
+                                       __psunsigned_t, __psunsigned_t,
+                                       __psunsigned_t, __psunsigned_t,
+                                       __psunsigned_t, __psunsigned_t);
+        void            (*trace_cursor)(struct xfs_btree_cur *, __uint32_t *,
+                                        __uint64_t *, __uint64_t *);
+        void            (*trace_key)(struct xfs_btree_cur *,
+                                     union xfs_btree_key *, __uint64_t *,
+                                     __uint64_t *);
+        void            (*trace_record)(struct xfs_btree_cur *,
+                                        union xfs_btree_rec *, __uint64_t *,
+                                        __uint64_t *, __uint64_t *);
+#endif
+};
+
+/*
+ * Reasons for the update_lastrec method to be called.
+ */
+#define LASTREC_UPDATE  0
+#define LASTREC_INSREC  1
+#define LASTREC_DELREC  2
+
+
 /*
  * Btree cursor structure.
  * This collects all information needed by the btree code in one place.
@@ -144,6 +238,8 @@ typedef struct xfs_btree_cur
 {
         struct xfs_trans        *bc_tp; /* transaction we're in, if any */
         struct xfs_mount        *bc_mp; /* file system mount struct */
+        const struct xfs_btree_ops *bc_ops;
+        uint                    bc_flags; /* btree features - below */
         union {
                 xfs_alloc_rec_incore_t  a;
                 xfs_bmbt_irec_t         b;
@@ -175,94 +271,40 @@ typedef struct xfs_btree_cur
         }               bc_private;     /* per-btree type data */
 } xfs_btree_cur_t;
 
+/* cursor flags */
+#define XFS_BTREE_LONG_PTRS             (1<<0)  /* pointers are 64bits long */
+#define XFS_BTREE_ROOT_IN_INODE         (1<<1)  /* root may be variable size */
+#define XFS_BTREE_LASTREC_UPDATE        (1<<2)  /* track last rec externally */
+
+
 #define XFS_BTREE_NOERROR       0
 #define XFS_BTREE_ERROR         1
 
 /*
  * Convert from buffer to btree block header.
  */
-#define XFS_BUF_TO_BLOCK(bp)    ((xfs_btree_block_t *)XFS_BUF_PTR(bp))
-#define XFS_BUF_TO_LBLOCK(bp)   ((xfs_btree_lblock_t *)XFS_BUF_PTR(bp))
-#define XFS_BUF_TO_SBLOCK(bp)   ((xfs_btree_sblock_t *)XFS_BUF_PTR(bp))
+#define XFS_BUF_TO_BLOCK(bp)    ((struct xfs_btree_block *)XFS_BUF_PTR(bp))
 
 
-#ifdef __KERNEL__
-
-#ifdef DEBUG
 /*
- * Debug routine: check that block header is ok.
+ * Check that block header is ok.
  */
-void
+int
 xfs_btree_check_block(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        xfs_btree_block_t       *block, /* generic btree block pointer */
-        int                     level,  /* level of the btree block */
-        struct xfs_buf          *bp);   /* buffer containing block, if any */
-
-/*
- * Debug routine: check that keys are in the right order.
- */
-void
-xfs_btree_check_key(
-        xfs_btnum_t             btnum,  /* btree identifier */
-        void                    *ak1,   /* pointer to left (lower) key */
-        void                    *ak2);  /* pointer to right (higher) key */
-
-/*
- * Debug routine: check that records are in the right order.
- */
-void
-xfs_btree_check_rec(
-        xfs_btnum_t             btnum,  /* btree identifier */
-        void                    *ar1,   /* pointer to left (lower) record */
-        void                    *ar2);  /* pointer to right (higher) record */
-#else
-#define xfs_btree_check_block(a,b,c,d)
-#define xfs_btree_check_key(a,b,c)
-#define xfs_btree_check_rec(a,b,c)
-#endif  /* DEBUG */
-
-/*
- * Checking routine: check that long form block header is ok.
- */
-int                                     /* error (0 or EFSCORRUPTED) */
-xfs_btree_check_lblock(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        xfs_btree_lblock_t      *block, /* btree long form block pointer */
+        struct xfs_btree_cur    *cur,   /* btree cursor */
+        struct xfs_btree_block  *block, /* generic btree block pointer */
         int                     level,  /* level of the btree block */
         struct xfs_buf          *bp);   /* buffer containing block, if any */
 
 /*
- * Checking routine: check that (long) pointer is ok.
+ * Check that (long) pointer is ok.
  */
 int                                     /* error (0 or EFSCORRUPTED) */
 xfs_btree_check_lptr(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
+        struct xfs_btree_cur    *cur,   /* btree cursor */
         xfs_dfsbno_t            ptr,    /* btree block disk address */
         int                     level); /* btree block level */
 
-#define xfs_btree_check_lptr_disk(cur, ptr, level) \
-        xfs_btree_check_lptr(cur, be64_to_cpu(ptr), level)
-
-/*
- * Checking routine: check that short form block header is ok.
- */
-int                                     /* error (0 or EFSCORRUPTED) */
-xfs_btree_check_sblock(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        xfs_btree_sblock_t      *block, /* btree short form block pointer */
-        int                     level,  /* level of the btree block */
-        struct xfs_buf          *bp);   /* buffer containing block */
-
-/*
- * Checking routine: check that (short) pointer is ok.
- */
-int                                     /* error (0 or EFSCORRUPTED) */
-xfs_btree_check_sptr(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        xfs_agblock_t           ptr,    /* btree block disk address */
-        int                     level); /* btree block level */
-
 /*
  * Delete the btree cursor.
  */
@@ -281,15 +323,6 @@ xfs_btree_dup_cursor(
         xfs_btree_cur_t         **ncur);/* output cursor */
 
 /*
- * Change the cursor to point to the first record in the current block
- * at the given level.  Other levels are unaffected.
- */
-int                                     /* success=1, failure=0 */
-xfs_btree_firstrec(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        int                     level); /* level to change */
-
-/*
  * Get a buffer for the block, return it with no data read.
  * Long-form addressing.
  */
@@ -313,20 +346,6 @@ xfs_btree_get_bufs(
         uint                    lock);  /* lock flags for get_buf */
 
 /*
- * Allocate a new btree cursor.
- * The cursor is either for allocation (A) or bmap (B).
- */
-xfs_btree_cur_t *                       /* new btree cursor */
-xfs_btree_init_cursor(
-        struct xfs_mount        *mp,    /* file system mount point */
-        struct xfs_trans        *tp,    /* transaction pointer */
-        struct xfs_buf          *agbp,  /* (A only) buffer for agf structure */
-        xfs_agnumber_t          agno,   /* (A only) allocation group number */
-        xfs_btnum_t             btnum,  /* btree identifier */
-        struct xfs_inode        *ip,    /* (B only) inode owning the btree */
-        int                     whichfork); /* (B only) data/attr fork */
-
-/*
  * Check for the cursor referring to the last block at the given level.
  */
 int                                     /* 1=is last block, 0=not last block */
@@ -335,15 +354,6 @@ xfs_btree_islastblock(
         int                     level); /* level to check */
 
 /*
- * Change the cursor to point to the last record in the current block
- * at the given level.  Other levels are unaffected.
- */
-int                                     /* success=1, failure=0 */
-xfs_btree_lastrec(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        int                     level); /* level to change */
-
-/*
  * Compute first and last byte offsets for the fields given.
  * Interprets the offsets table, which contains struct field offsets.
  */
@@ -404,39 +414,53 @@ xfs_btree_reada_bufs(
         xfs_extlen_t            count); /* count of filesystem blocks */
 
 /*
- * Read-ahead btree blocks, at the given level.
- * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
+ * Set the buffer for level "lev" in the cursor to bp, releasing
+ * any previous buffer.
  */
-int                                     /* readahead block count */
-xfs_btree_readahead_core(
+void
+xfs_btree_setbuf(
         xfs_btree_cur_t         *cur,   /* btree cursor */
         int                     lev,    /* level in btree */
-        int                     lr);    /* left/right bits */
+        struct xfs_buf          *bp);   /* new buffer to set */
 
-static inline int                       /* readahead block count */
-xfs_btree_readahead(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        int                     lev,    /* level in btree */
-        int                     lr)     /* left/right bits */
-{
-        if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
-                return 0;
 
-        return xfs_btree_readahead_core(cur, lev, lr);
-}
+/*
+ * Common btree core entry points.
+ */
+int xfs_btree_increment(struct xfs_btree_cur *, int, int *);
+int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
+int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
+int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
+int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *);
+int xfs_btree_kill_iroot(struct xfs_btree_cur *);
+int xfs_btree_insert(struct xfs_btree_cur *, int *);
+int xfs_btree_delete(struct xfs_btree_cur *, int *);
+int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *);
 
+/*
+ * Internal btree helpers also used by xfs_bmap.c.
+ */
+void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, int);
+void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int);
 
 /*
- * Set the buffer for level "lev" in the cursor to bp, releasing
- * any previous buffer.
+ * Helpers.
  */
-void
-xfs_btree_setbuf(
-        xfs_btree_cur_t         *cur,   /* btree cursor */
-        int                     lev,    /* level in btree */
-        struct xfs_buf          *bp);   /* new buffer to set */
+static inline int xfs_btree_get_numrecs(struct xfs_btree_block *block)
+{
+        return be16_to_cpu(block->bb_numrecs);
+}
+
+static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
+                __uint16_t numrecs)
+{
+        block->bb_numrecs = cpu_to_be16(numrecs);
+}
 
-#endif  /* __KERNEL__ */
+static inline int xfs_btree_get_level(struct xfs_btree_block *block)
+{
+        return be16_to_cpu(block->bb_level);
+}
 
 
 /*