[XFS] implement generic xfs_btree_get_rec

Not really much reason to make it generic given that it's so small, but
this is the last non-method in xfs_alloc_btree.c and xfs_ialloc_btree.c,
so it makes the whole btree implementation more structured.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32206a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>

fs/xfs/xfs_alloc.c

@@ -154,6 +154,27 @@ xfs_alloc_update(
 	return xfs_btree_update(cur, &rec);
 }
 
+/*
+ * Get the data from the pointed-to record.
+ */
+STATIC int				/* error */
+xfs_alloc_get_rec(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_agblock_t		*bno,	/* output: starting block of extent */
+	xfs_extlen_t		*len,	/* output: length of extent */
+	int			*stat)	/* output: success/failure */
+{
+	union xfs_btree_rec	*rec;
+	int			error;
+
+	error = xfs_btree_get_rec(cur, &rec, stat);
+	if (!error && *stat == 1) {
+		*bno = be32_to_cpu(rec->alloc.ar_startblock);
+		*len = be32_to_cpu(rec->alloc.ar_blockcount);
+	}
+	return error;
+}
+
 /*
  * Compute aligned version of the found extent.
  * Takes alignment and min length into account.

fs/xfs/xfs_alloc_btree.c

@@ -41,50 +41,6 @@
 #include "xfs_error.h"
 
 
-/*
- * Get the data from the pointed-to record.
- */
-int					/* error */
-xfs_alloc_get_rec(
-	xfs_btree_cur_t		*cur,	/* btree cursor */
-	xfs_agblock_t		*bno,	/* output: starting block of extent */
-	xfs_extlen_t		*len,	/* output: length of extent */
-	int			*stat)	/* output: success/failure */
-{
-	xfs_alloc_block_t	*block;	/* btree block */
-#ifdef DEBUG
-	int			error;	/* error return value */
-#endif
-	int			ptr;	/* record number */
-
-	ptr = cur->bc_ptrs[0];
-	block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[0]);
-#ifdef DEBUG
-	if ((error = xfs_btree_check_sblock(cur, block, 0, cur->bc_bufs[0])))
-		return error;
-#endif
-	/*
-	 * Off the right end or left end, return failure.
-	 */
-	if (ptr > be16_to_cpu(block->bb_numrecs) || ptr <= 0) {
-		*stat = 0;
-		return 0;
-	}
-	/*
-	 * Point to the record and extract its data.
-	 */
-	{
-		xfs_alloc_rec_t		*rec;	/* record data */
-
-		rec = XFS_ALLOC_REC_ADDR(block, ptr, cur);
-		*bno = be32_to_cpu(rec->ar_startblock);
-		*len = be32_to_cpu(rec->ar_blockcount);
-	}
-	*stat = 1;
-	return 0;
-}
-
-
 STATIC struct xfs_btree_cur *
 xfs_allocbt_dup_cursor(
 	struct xfs_btree_cur	*cur)

fs/xfs/xfs_alloc_btree.h

@@ -94,12 +94,6 @@ typedef	struct xfs_btree_sblock xfs_alloc_block_t;
 #define	XFS_ALLOC_PTR_ADDR(bb,i,cur)	\
 	XFS_BTREE_PTR_ADDR(xfs_alloc, bb, i, XFS_ALLOC_BLOCK_MAXRECS(1, cur))
 
-/*
- * Get the data from the pointed-to record.
- */
-extern int xfs_alloc_get_rec(struct xfs_btree_cur *cur,	xfs_agblock_t *bno,
-				xfs_extlen_t *len, int *stat);
-
 
 extern struct xfs_btree_cur *xfs_allocbt_init_cursor(struct xfs_mount *,
 		struct xfs_trans *, struct xfs_buf *,

fs/xfs/xfs_btree.c

@@ -3764,3 +3764,44 @@ error0:
 	XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
 	return error;
 }
+
+/*
+ * Get the data from the pointed-to record.
+ */
+int					/* error */
+xfs_btree_get_rec(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	union xfs_btree_rec	**recp,	/* output: btree record */
+	int			*stat)	/* output: success/failure */
+{
+	struct xfs_btree_block	*block;	/* btree block */
+	struct xfs_buf		*bp;	/* buffer pointer */
+	int			ptr;	/* record number */
+#ifdef DEBUG
+	int			error;	/* error return value */
+#endif
+
+	ptr = cur->bc_ptrs[0];
+	block = xfs_btree_get_block(cur, 0, &bp);
+
+#ifdef DEBUG
+	error = xfs_btree_check_block(cur, block, 0, bp);
+	if (error)
+		return error;
+#endif
+
+	/*
+	 * Off the right end or left end, return failure.
+	 */
+	if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
+		*stat = 0;
+		return 0;
+	}
+
+	/*
+	 * Point to the record and extract its data.
+	 */
+	*recp = xfs_btree_rec_addr(cur, ptr, block);
+	*stat = 1;
+	return 0;
+}

fs/xfs/xfs_btree.h

@@ -567,6 +567,7 @@ 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 *);
 
 /*
  * Helpers.

fs/xfs/xfs_ialloc.c

@@ -191,6 +191,29 @@ xfs_inobt_update(
 	return xfs_btree_update(cur, &rec);
 }
 
+/*
+ * Get the data from the pointed-to record.
+ */
+int					/* error */
+xfs_inobt_get_rec(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_agino_t		*ino,	/* output: starting inode of chunk */
+	__int32_t		*fcnt,	/* output: number of free inodes */
+	xfs_inofree_t		*free,	/* output: free inode mask */
+	int			*stat)	/* output: success/failure */
+{
+	union xfs_btree_rec	*rec;
+	int			error;
+
+	error = xfs_btree_get_rec(cur, &rec, stat);
+	if (!error && *stat == 1) {
+		*ino = be32_to_cpu(rec->inobt.ir_startino);
+		*fcnt = be32_to_cpu(rec->inobt.ir_freecount);
+		*free = be64_to_cpu(rec->inobt.ir_free);
+	}
+	return error;
+}
+
 /*
  * Allocate new inodes in the allocation group specified by agbp.
  * Return 0 for success, else error code.

fs/xfs/xfs_ialloc.h

@@ -168,6 +168,11 @@ int xfs_inobt_lookup_ge(struct xfs_btree_cur *cur, xfs_agino_t ino,
 int xfs_inobt_lookup_le(struct xfs_btree_cur *cur, xfs_agino_t ino,
 		__int32_t fcnt,	xfs_inofree_t free, int *stat);
 
+/*
+ * Get the data from the pointed-to record.
+ */
+extern int xfs_inobt_get_rec(struct xfs_btree_cur *cur, xfs_agino_t *ino,
+			     __int32_t *fcnt, xfs_inofree_t *free, int *stat);
 
 #endif	/* __KERNEL__ */
 

fs/xfs/xfs_ialloc_btree.c

@@ -41,50 +41,6 @@
 #include "xfs_error.h"
 
 
-/*
- * Get the data from the pointed-to record.
- */
-int					/* error */
-xfs_inobt_get_rec(
-	xfs_btree_cur_t		*cur,	/* btree cursor */
-	xfs_agino_t		*ino,	/* output: starting inode of chunk */
-	__int32_t		*fcnt,	/* output: number of free inodes */
-	xfs_inofree_t		*free,	/* output: free inode mask */
-	int			*stat)	/* output: success/failure */
-{
-	xfs_inobt_block_t	*block;	/* btree block */
-	xfs_buf_t		*bp;	/* buffer containing btree block */
-#ifdef DEBUG
-	int			error;	/* error return value */
-#endif
-	int			ptr;	/* record number */
-	xfs_inobt_rec_t		*rec;	/* record data */
-
-	bp = cur->bc_bufs[0];
-	ptr = cur->bc_ptrs[0];
-	block = XFS_BUF_TO_INOBT_BLOCK(bp);
-#ifdef DEBUG
-	if ((error = xfs_btree_check_sblock(cur, block, 0, bp)))
-		return error;
-#endif
-	/*
-	 * Off the right end or left end, return failure.
-	 */
-	if (ptr > be16_to_cpu(block->bb_numrecs) || ptr <= 0) {
-		*stat = 0;
-		return 0;
-	}
-	/*
-	 * Point to the record and extract its data.
-	 */
-	rec = XFS_INOBT_REC_ADDR(block, ptr, cur);
-	*ino = be32_to_cpu(rec->ir_startino);
-	*fcnt = be32_to_cpu(rec->ir_freecount);
-	*free = be64_to_cpu(rec->ir_free);
-	*stat = 1;
-	return 0;
-}
-
 STATIC int
 xfs_inobt_get_minrecs(
 	struct xfs_btree_cur	*cur,

fs/xfs/xfs_ialloc_btree.h

@@ -116,13 +116,6 @@ typedef	struct xfs_btree_sblock xfs_inobt_block_t;
 	(XFS_BTREE_PTR_ADDR(xfs_inobt, bb, \
 				i, XFS_INOBT_BLOCK_MAXRECS(1, cur)))
 
-/*
- * Get the data from the pointed-to record.
- */
-extern int xfs_inobt_get_rec(struct xfs_btree_cur *cur, xfs_agino_t *ino,
-			     __int32_t *fcnt, xfs_inofree_t *free, int *stat);
-
-
 extern struct xfs_btree_cur *xfs_inobt_init_cursor(struct xfs_mount *,
 		struct xfs_trans *, struct xfs_buf *, xfs_agnumber_t);