1 files changed, 272 insertions, 177 deletions

diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c
index aad8c5da38af..e6ebbaeb4dc6 100644
--- a/fs/xfs/xfs_ialloc.c
+++ b/fs/xfs/xfs_ialloc.c
@@ -41,68 +41,6 @@
 #include "xfs_error.h"
 #include "xfs_bmap.h"
 
-/*
- * Log specified fields for the inode given by bp and off.
- */
-STATIC void
-xfs_ialloc_log_di(
-	xfs_trans_t	*tp,		/* transaction pointer */
-	xfs_buf_t	*bp,		/* inode buffer */
-	int		off,		/* index of inode in buffer */
-	int		fields)		/* bitmask of fields to log */
-{
-	int			first;		/* first byte number */
-	int			ioffset;	/* off in bytes */
-	int			last;		/* last byte number */
-	xfs_mount_t		*mp;		/* mount point structure */
-	static const short	offsets[] = {	/* field offsets */
-						/* keep in sync with bits */
-		offsetof(xfs_dinode_core_t, di_magic),
-		offsetof(xfs_dinode_core_t, di_mode),
-		offsetof(xfs_dinode_core_t, di_version),
-		offsetof(xfs_dinode_core_t, di_format),
-		offsetof(xfs_dinode_core_t, di_onlink),
-		offsetof(xfs_dinode_core_t, di_uid),
-		offsetof(xfs_dinode_core_t, di_gid),
-		offsetof(xfs_dinode_core_t, di_nlink),
-		offsetof(xfs_dinode_core_t, di_projid),
-		offsetof(xfs_dinode_core_t, di_pad),
-		offsetof(xfs_dinode_core_t, di_atime),
-		offsetof(xfs_dinode_core_t, di_mtime),
-		offsetof(xfs_dinode_core_t, di_ctime),
-		offsetof(xfs_dinode_core_t, di_size),
-		offsetof(xfs_dinode_core_t, di_nblocks),
-		offsetof(xfs_dinode_core_t, di_extsize),
-		offsetof(xfs_dinode_core_t, di_nextents),
-		offsetof(xfs_dinode_core_t, di_anextents),
-		offsetof(xfs_dinode_core_t, di_forkoff),
-		offsetof(xfs_dinode_core_t, di_aformat),
-		offsetof(xfs_dinode_core_t, di_dmevmask),
-		offsetof(xfs_dinode_core_t, di_dmstate),
-		offsetof(xfs_dinode_core_t, di_flags),
-		offsetof(xfs_dinode_core_t, di_gen),
-		offsetof(xfs_dinode_t, di_next_unlinked),
-		offsetof(xfs_dinode_t, di_u),
-		offsetof(xfs_dinode_t, di_a),
-		sizeof(xfs_dinode_t)
-	};
-
-
-	ASSERT(offsetof(xfs_dinode_t, di_core) == 0);
-	ASSERT((fields & (XFS_DI_U|XFS_DI_A)) == 0);
-	mp = tp->t_mountp;
-	/*
-	 * Get the inode-relative first and last bytes for these fields
-	 */
-	xfs_btree_offsets(fields, offsets, XFS_DI_NUM_BITS, &first, &last);
-	/*
-	 * Convert to buffer offsets and log it.
-	 */
-	ioffset = off << mp->m_sb.sb_inodelog;
-	first += ioffset;
-	last += ioffset;
-	xfs_trans_log_buf(tp, bp, first, last);
-}
 
 /*
  * Allocation group level functions.
@@ -119,6 +57,102 @@ xfs_ialloc_cluster_alignment(
 }
 
 /*
+ * Lookup the record equal to ino in the btree given by cur.
+ */
+STATIC int				/* error */
+xfs_inobt_lookup_eq(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_agino_t		ino,	/* starting inode of chunk */
+	__int32_t		fcnt,	/* free inode count */
+	xfs_inofree_t		free,	/* free inode mask */
+	int			*stat)	/* success/failure */
+{
+	cur->bc_rec.i.ir_startino = ino;
+	cur->bc_rec.i.ir_freecount = fcnt;
+	cur->bc_rec.i.ir_free = free;
+	return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
+}
+
+/*
+ * Lookup the first record greater than or equal to ino
+ * in the btree given by cur.
+ */
+int					/* error */
+xfs_inobt_lookup_ge(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_agino_t		ino,	/* starting inode of chunk */
+	__int32_t		fcnt,	/* free inode count */
+	xfs_inofree_t		free,	/* free inode mask */
+	int			*stat)	/* success/failure */
+{
+	cur->bc_rec.i.ir_startino = ino;
+	cur->bc_rec.i.ir_freecount = fcnt;
+	cur->bc_rec.i.ir_free = free;
+	return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
+}
+
+/*
+ * Lookup the first record less than or equal to ino
+ * in the btree given by cur.
+ */
+int					/* error */
+xfs_inobt_lookup_le(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_agino_t		ino,	/* starting inode of chunk */
+	__int32_t		fcnt,	/* free inode count */
+	xfs_inofree_t		free,	/* free inode mask */
+	int			*stat)	/* success/failure */
+{
+	cur->bc_rec.i.ir_startino = ino;
+	cur->bc_rec.i.ir_freecount = fcnt;
+	cur->bc_rec.i.ir_free = free;
+	return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
+}
+
+/*
+ * Update the record referred to by cur to the value given
+ * by [ino, fcnt, free].
+ * This either works (return 0) or gets an EFSCORRUPTED error.
+ */
+STATIC int				/* error */
+xfs_inobt_update(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_agino_t		ino,	/* starting inode of chunk */
+	__int32_t		fcnt,	/* free inode count */
+	xfs_inofree_t		free)	/* free inode mask */
+{
+	union xfs_btree_rec	rec;
+
+	rec.inobt.ir_startino = cpu_to_be32(ino);
+	rec.inobt.ir_freecount = cpu_to_be32(fcnt);
+	rec.inobt.ir_free = cpu_to_be64(free);
+	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.
  */
@@ -287,9 +321,9 @@ xfs_ialloc_ag_alloc(
 	 * able to use the file system.
 	 */
 	if (xfs_sb_version_hasnlink(&args.mp->m_sb))
-		version = XFS_DINODE_VERSION_2;
+		version = 2;
 	else
-		version = XFS_DINODE_VERSION_1;
+		version = 1;
 
 	/*
 	 * Seed the new inode cluster with a random generation number. This
@@ -310,18 +344,25 @@ xfs_ialloc_ag_alloc(
 					 XFS_BUF_LOCK);
 		ASSERT(fbuf);
 		ASSERT(!XFS_BUF_GETERROR(fbuf));
+
 		/*
-		 * Set initial values for the inodes in this buffer.
+		 * Initialize all inodes in this buffer and then log them.
+		 *
+		 * XXX: It would be much better if we had just one transaction to
+		 *      log a whole cluster of inodes instead of all the indivdual
+		 *      transactions causing a lot of log traffic.
 		 */
 		xfs_biozero(fbuf, 0, ninodes << args.mp->m_sb.sb_inodelog);
 		for (i = 0; i < ninodes; i++) {
+			int	ioffset = i << args.mp->m_sb.sb_inodelog;
+			uint	isize = sizeof(struct xfs_dinode);
+
 			free = XFS_MAKE_IPTR(args.mp, fbuf, i);
-			free->di_core.di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
-			free->di_core.di_version = version;
-			free->di_core.di_gen = cpu_to_be32(gen);
+			free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
+			free->di_version = version;
+			free->di_gen = cpu_to_be32(gen);
 			free->di_next_unlinked = cpu_to_be32(NULLAGINO);
-			xfs_ialloc_log_di(tp, fbuf, i,
-				XFS_DI_CORE_BITS | XFS_DI_NEXT_UNLINKED);
+			xfs_trans_log_buf(tp, fbuf, ioffset, ioffset + isize - 1);
 		}
 		xfs_trans_inode_alloc_buf(tp, fbuf);
 	}
@@ -335,8 +376,7 @@ xfs_ialloc_ag_alloc(
 	/*
 	 * Insert records describing the new inode chunk into the btree.
 	 */
-	cur = xfs_btree_init_cursor(args.mp, tp, agbp, agno,
-			XFS_BTNUM_INO, (xfs_inode_t *)0, 0);
+	cur = xfs_inobt_init_cursor(args.mp, tp, agbp, agno);
 	for (thisino = newino;
 	     thisino < newino + newlen;
 	     thisino += XFS_INODES_PER_CHUNK) {
@@ -346,7 +386,7 @@ xfs_ialloc_ag_alloc(
 			return error;
 		}
 		ASSERT(i == 0);
-		if ((error = xfs_inobt_insert(cur, &i))) {
+		if ((error = xfs_btree_insert(cur, &i))) {
 			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 			return error;
 		}
@@ -676,8 +716,7 @@ nextag:
 	 */
 	agno = tagno;
 	*IO_agbp = NULL;
-	cur = xfs_btree_init_cursor(mp, tp, agbp, be32_to_cpu(agi->agi_seqno),
-				    XFS_BTNUM_INO, (xfs_inode_t *)0, 0);
+	cur = xfs_inobt_init_cursor(mp, tp, agbp, be32_to_cpu(agi->agi_seqno));
 	/*
 	 * If pagino is 0 (this is the root inode allocation) use newino.
 	 * This must work because we've just allocated some.
@@ -697,7 +736,7 @@ nextag:
 				goto error0;
 			XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
 			freecount += rec.ir_freecount;
-			if ((error = xfs_inobt_increment(cur, 0, &i)))
+			if ((error = xfs_btree_increment(cur, 0, &i)))
 				goto error0;
 		} while (i == 1);
 
@@ -741,7 +780,7 @@ nextag:
 			/*
 			 * Search left with tcur, back up 1 record.
 			 */
-			if ((error = xfs_inobt_decrement(tcur, 0, &i)))
+			if ((error = xfs_btree_decrement(tcur, 0, &i)))
 				goto error1;
 			doneleft = !i;
 			if (!doneleft) {
@@ -755,7 +794,7 @@ nextag:
 			/*
 			 * Search right with cur, go forward 1 record.
 			 */
-			if ((error = xfs_inobt_increment(cur, 0, &i)))
+			if ((error = xfs_btree_increment(cur, 0, &i)))
 				goto error1;
 			doneright = !i;
 			if (!doneright) {
@@ -817,7 +856,7 @@ nextag:
 				 * further left.
 				 */
 				if (useleft) {
-					if ((error = xfs_inobt_decrement(tcur, 0,
+					if ((error = xfs_btree_decrement(tcur, 0,
 							&i)))
 						goto error1;
 					doneleft = !i;
@@ -837,7 +876,7 @@ nextag:
 				 * further right.
 				 */
 				else {
-					if ((error = xfs_inobt_increment(cur, 0,
+					if ((error = xfs_btree_increment(cur, 0,
 							&i)))
 						goto error1;
 					doneright = !i;
@@ -892,7 +931,7 @@ nextag:
 				XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
 				if (rec.ir_freecount > 0)
 					break;
-				if ((error = xfs_inobt_increment(cur, 0, &i)))
+				if ((error = xfs_btree_increment(cur, 0, &i)))
 					goto error0;
 				XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
 			}
@@ -926,7 +965,7 @@ nextag:
 				goto error0;
 			XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
 			freecount += rec.ir_freecount;
-			if ((error = xfs_inobt_increment(cur, 0, &i)))
+			if ((error = xfs_btree_increment(cur, 0, &i)))
 				goto error0;
 		} while (i == 1);
 		ASSERT(freecount == be32_to_cpu(agi->agi_freecount) ||
@@ -1022,8 +1061,7 @@ xfs_difree(
 	/*
 	 * Initialize the cursor.
 	 */
-	cur = xfs_btree_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO,
-		(xfs_inode_t *)0, 0);
+	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
 #ifdef DEBUG
 	if (cur->bc_nlevels == 1) {
 		int freecount = 0;
@@ -1036,7 +1074,7 @@ xfs_difree(
 				goto error0;
 			if (i) {
 				freecount += rec.ir_freecount;
-				if ((error = xfs_inobt_increment(cur, 0, &i)))
+				if ((error = xfs_btree_increment(cur, 0, &i)))
 					goto error0;
 			}
 		} while (i == 1);
@@ -1098,8 +1136,8 @@ xfs_difree(
 		xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
 		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
 
-		if ((error = xfs_inobt_delete(cur, &i))) {
-			cmn_err(CE_WARN, "xfs_difree: xfs_inobt_delete returned an error %d on %s.\n",
+		if ((error = xfs_btree_delete(cur, &i))) {
+			cmn_err(CE_WARN, "xfs_difree: xfs_btree_delete returned an error %d on %s.\n",
 				error, mp->m_fsname);
 			goto error0;
 		}
@@ -1141,7 +1179,7 @@ xfs_difree(
 				goto error0;
 			if (i) {
 				freecount += rec.ir_freecount;
-				if ((error = xfs_inobt_increment(cur, 0, &i)))
+				if ((error = xfs_btree_increment(cur, 0, &i)))
 					goto error0;
 			}
 		} while (i == 1);
@@ -1158,36 +1196,28 @@ error0:
 }
 
 /*
- * Return the location of the inode in bno/off, for mapping it into a buffer.
+ * Return the location of the inode in imap, for mapping it into a buffer.
  */
-/*ARGSUSED*/
 int
-xfs_dilocate(
-	xfs_mount_t	*mp,	/* file system mount structure */
-	xfs_trans_t	*tp,	/* transaction pointer */
+xfs_imap(
+	xfs_mount_t	 *mp,	/* file system mount structure */
+	xfs_trans_t	 *tp,	/* transaction pointer */
 	xfs_ino_t	ino,	/* inode to locate */
-	xfs_fsblock_t	*bno,	/* output: block containing inode */
-	int		*len,	/* output: num blocks in inode cluster */
-	int		*off,	/* output: index in block of inode */
-	uint		flags)	/* flags concerning inode lookup */
+	struct xfs_imap	*imap,	/* location map structure */
+	uint		flags)	/* flags for inode btree lookup */
 {
 	xfs_agblock_t	agbno;	/* block number of inode in the alloc group */
-	xfs_buf_t	*agbp;	/* agi buffer */
 	xfs_agino_t	agino;	/* inode number within alloc group */
 	xfs_agnumber_t	agno;	/* allocation group number */
 	int		blks_per_cluster; /* num blocks per inode cluster */
 	xfs_agblock_t	chunk_agbno;	/* first block in inode chunk */
-	xfs_agino_t	chunk_agino;	/* first agino in inode chunk */
-	__int32_t	chunk_cnt;	/* count of free inodes in chunk */
-	xfs_inofree_t	chunk_free;	/* mask of free inodes in chunk */
 	xfs_agblock_t	cluster_agbno;	/* first block in inode cluster */
-	xfs_btree_cur_t	*cur;	/* inode btree cursor */
 	int		error;	/* error code */
-	int		i;	/* temp state */
 	int		offset;	/* index of inode in its buffer */
 	int		offset_agbno;	/* blks from chunk start to inode */
 
 	ASSERT(ino != NULLFSINO);
+
 	/*
 	 * Split up the inode number into its parts.
 	 */
@@ -1198,24 +1228,24 @@ xfs_dilocate(
 	    ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
 #ifdef DEBUG
 		/* no diagnostics for bulkstat, ino comes from userspace */
-		if (flags & XFS_IMAP_BULKSTAT)
+		if (flags & XFS_IGET_BULKSTAT)
 			return XFS_ERROR(EINVAL);
 		if (agno >= mp->m_sb.sb_agcount) {
 			xfs_fs_cmn_err(CE_ALERT, mp,
-					"xfs_dilocate: agno (%d) >= "
+					"xfs_imap: agno (%d) >= "
 					"mp->m_sb.sb_agcount (%d)",
 					agno,  mp->m_sb.sb_agcount);
 		}
 		if (agbno >= mp->m_sb.sb_agblocks) {
 			xfs_fs_cmn_err(CE_ALERT, mp,
-					"xfs_dilocate: agbno (0x%llx) >= "
+					"xfs_imap: agbno (0x%llx) >= "
 					"mp->m_sb.sb_agblocks (0x%lx)",
 					(unsigned long long) agbno,
 					(unsigned long) mp->m_sb.sb_agblocks);
 		}
 		if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
 			xfs_fs_cmn_err(CE_ALERT, mp,
-					"xfs_dilocate: ino (0x%llx) != "
+					"xfs_imap: ino (0x%llx) != "
 					"XFS_AGINO_TO_INO(mp, agno, agino) "
 					"(0x%llx)",
 					ino, XFS_AGINO_TO_INO(mp, agno, agino));
@@ -1224,65 +1254,89 @@ xfs_dilocate(
 #endif /* DEBUG */
 		return XFS_ERROR(EINVAL);
 	}
-	if ((mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) ||
-	    !(flags & XFS_IMAP_LOOKUP)) {
+
+	/*
+	 * If the inode cluster size is the same as the blocksize or
+	 * smaller we get to the buffer by simple arithmetics.
+	 */
+	if (XFS_INODE_CLUSTER_SIZE(mp) <= mp->m_sb.sb_blocksize) {
 		offset = XFS_INO_TO_OFFSET(mp, ino);
 		ASSERT(offset < mp->m_sb.sb_inopblock);
-		*bno = XFS_AGB_TO_FSB(mp, agno, agbno);
-		*off = offset;
-		*len = 1;
+
+		imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
+		imap->im_len = XFS_FSB_TO_BB(mp, 1);
+		imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
 		return 0;
 	}
+
 	blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_blocklog;
-	if (*bno != NULLFSBLOCK) {
+
+	/*
+	 * If we get a block number passed from bulkstat we can use it to
+	 * find the buffer easily.
+	 */
+	if (imap->im_blkno) {
 		offset = XFS_INO_TO_OFFSET(mp, ino);
 		ASSERT(offset < mp->m_sb.sb_inopblock);
-		cluster_agbno = XFS_FSB_TO_AGBNO(mp, *bno);
-		*off = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
-			offset;
-		*len = blks_per_cluster;
+
+		cluster_agbno = XFS_DADDR_TO_AGBNO(mp, imap->im_blkno);
+		offset += (agbno - cluster_agbno) * mp->m_sb.sb_inopblock;
+
+		imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster);
+		imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
 		return 0;
 	}
+
+	/*
+	 * If the inode chunks are aligned then use simple maths to
+	 * find the location. Otherwise we have to do a btree
+	 * lookup to find the location.
+	 */
 	if (mp->m_inoalign_mask) {
 		offset_agbno = agbno & mp->m_inoalign_mask;
 		chunk_agbno = agbno - offset_agbno;
 	} else {
+		xfs_btree_cur_t	*cur;	/* inode btree cursor */
+		xfs_agino_t	chunk_agino; /* first agino in inode chunk */
+		__int32_t	chunk_cnt; /* count of free inodes in chunk */
+		xfs_inofree_t	chunk_free; /* mask of free inodes in chunk */
+		xfs_buf_t	*agbp;	/* agi buffer */
+		int		i;	/* temp state */
+
 		down_read(&mp->m_peraglock);
 		error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
 		up_read(&mp->m_peraglock);
 		if (error) {
-#ifdef DEBUG
-			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_dilocate: "
+			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: "
 					"xfs_ialloc_read_agi() returned "
 					"error %d, agno %d",
 					error, agno);
-#endif /* DEBUG */
 			return error;
 		}
-		cur = xfs_btree_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO,
-			(xfs_inode_t *)0, 0);
-		if ((error = xfs_inobt_lookup_le(cur, agino, 0, 0, &i))) {
-#ifdef DEBUG
-			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_dilocate: "
+
+		cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
+		error = xfs_inobt_lookup_le(cur, agino, 0, 0, &i);
+		if (error) {
+			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: "
 					"xfs_inobt_lookup_le() failed");
-#endif /* DEBUG */
 			goto error0;
 		}
-		if ((error = xfs_inobt_get_rec(cur, &chunk_agino, &chunk_cnt,
-				&chunk_free, &i))) {
-#ifdef DEBUG
-			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_dilocate: "
+
+		error = xfs_inobt_get_rec(cur, &chunk_agino, &chunk_cnt,
+				&chunk_free, &i);
+		if (error) {
+			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: "
 					"xfs_inobt_get_rec() failed");
-#endif /* DEBUG */
 			goto error0;
 		}
 		if (i == 0) {
 #ifdef DEBUG
-			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_dilocate: "
+			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: "
 					"xfs_inobt_get_rec() failed");
 #endif /* DEBUG */
 			error = XFS_ERROR(EINVAL);
 		}
+ error0:
 		xfs_trans_brelse(tp, agbp);
 		xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 		if (error)
@@ -1290,19 +1344,35 @@ xfs_dilocate(
 		chunk_agbno = XFS_AGINO_TO_AGBNO(mp, chunk_agino);
 		offset_agbno = agbno - chunk_agbno;
 	}
+
 	ASSERT(agbno >= chunk_agbno);
 	cluster_agbno = chunk_agbno +
 		((offset_agbno / blks_per_cluster) * blks_per_cluster);
 	offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
 		XFS_INO_TO_OFFSET(mp, ino);
-	*bno = XFS_AGB_TO_FSB(mp, agno, cluster_agbno);
-	*off = offset;
-	*len = blks_per_cluster;
+
+	imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno);
+	imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster);
+	imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
+
+	/*
+	 * If the inode number maps to a block outside the bounds
+	 * of the file system then return NULL rather than calling
+	 * read_buf and panicing when we get an error from the
+	 * driver.
+	 */
+	if ((imap->im_blkno + imap->im_len) >
+	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
+		xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: "
+			"(imap->im_blkno (0x%llx) + imap->im_len (0x%llx)) > "
+			" XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks) (0x%llx)",
+			(unsigned long long) imap->im_blkno,
+			(unsigned long long) imap->im_len,
+			XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
+		return XFS_ERROR(EINVAL);
+	}
+
 	return 0;
-error0:
-	xfs_trans_brelse(tp, agbp);
-	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
-	return error;
 }
 
 /*
@@ -1370,70 +1440,95 @@ xfs_ialloc_log_agi(
 	xfs_trans_log_buf(tp, bp, first, last);
 }
 
+#ifdef DEBUG
+STATIC void
+xfs_check_agi_unlinked(
+	struct xfs_agi		*agi)
+{
+	int			i;
+
+	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
+		ASSERT(agi->agi_unlinked[i]);
+}
+#else
+#define xfs_check_agi_unlinked(agi)
+#endif
+
 /*
  * Read in the allocation group header (inode allocation section)
  */
 int
-xfs_ialloc_read_agi(
-	xfs_mount_t	*mp,		/* file system mount structure */
-	xfs_trans_t	*tp,		/* transaction pointer */
-	xfs_agnumber_t	agno,		/* allocation group number */
-	xfs_buf_t	**bpp)		/* allocation group hdr buf */
+xfs_read_agi(
+	struct xfs_mount	*mp,	/* file system mount structure */
+	struct xfs_trans	*tp,	/* transaction pointer */
+	xfs_agnumber_t		agno,	/* allocation group number */
+	struct xfs_buf		**bpp)	/* allocation group hdr buf */
 {
-	xfs_agi_t	*agi;		/* allocation group header */
-	int		agi_ok;		/* agi is consistent */
-	xfs_buf_t	*bp;		/* allocation group hdr buf */
-	xfs_perag_t	*pag;		/* per allocation group data */
-	int		error;
+	struct xfs_agi		*agi;	/* allocation group header */
+	int			agi_ok;	/* agi is consistent */
+	int			error;
 
 	ASSERT(agno != NULLAGNUMBER);
-	error = xfs_trans_read_buf(
-			mp, tp, mp->m_ddev_targp,
+
+	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
 			XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
-			XFS_FSS_TO_BB(mp, 1), 0, &bp);
+			XFS_FSS_TO_BB(mp, 1), 0, bpp);
 	if (error)
 		return error;
-	ASSERT(bp && !XFS_BUF_GETERROR(bp));
+
+	ASSERT(*bpp && !XFS_BUF_GETERROR(*bpp));
+	agi = XFS_BUF_TO_AGI(*bpp);
 
 	/*
 	 * Validate the magic number of the agi block.
 	 */
-	agi = XFS_BUF_TO_AGI(bp);
-	agi_ok =
-		be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC &&
-		XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum));
+	agi_ok = be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC &&
+		XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) &&
+		be32_to_cpu(agi->agi_seqno) == agno;
 	if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
 			XFS_RANDOM_IALLOC_READ_AGI))) {
-		XFS_CORRUPTION_ERROR("xfs_ialloc_read_agi", XFS_ERRLEVEL_LOW,
+		XFS_CORRUPTION_ERROR("xfs_read_agi", XFS_ERRLEVEL_LOW,
 				     mp, agi);
-		xfs_trans_brelse(tp, bp);
+		xfs_trans_brelse(tp, *bpp);
 		return XFS_ERROR(EFSCORRUPTED);
 	}
+
+	XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_AGI, XFS_AGI_REF);
+
+	xfs_check_agi_unlinked(agi);
+	return 0;
+}
+
+int
+xfs_ialloc_read_agi(
+	struct xfs_mount	*mp,	/* file system mount structure */
+	struct xfs_trans	*tp,	/* transaction pointer */
+	xfs_agnumber_t		agno,	/* allocation group number */
+	struct xfs_buf		**bpp)	/* allocation group hdr buf */
+{
+	struct xfs_agi		*agi;	/* allocation group header */
+	struct xfs_perag	*pag;	/* per allocation group data */
+	int			error;
+
+	error = xfs_read_agi(mp, tp, agno, bpp);
+	if (error)
+		return error;
+
+	agi = XFS_BUF_TO_AGI(*bpp);
 	pag = &mp->m_perag[agno];
+
 	if (!pag->pagi_init) {
 		pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
 		pag->pagi_count = be32_to_cpu(agi->agi_count);
 		pag->pagi_init = 1;
-	} else {
-		/*
-		 * It's possible for these to be out of sync if
-		 * we are in the middle of a forced shutdown.
-		 */
-		ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
-			XFS_FORCED_SHUTDOWN(mp));
 	}
 
-#ifdef DEBUG
-	{
-		int	i;
-
-		for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
-			ASSERT(agi->agi_unlinked[i]);
-	}
-#endif
-
-	XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGI, XFS_AGI_REF);
-	*bpp = bp;
+	/*
+	 * It's possible for these to be out of sync if
+	 * we are in the middle of a forced shutdown.
+	 */
+	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
+		XFS_FORCED_SHUTDOWN(mp));
 	return 0;
 }