xfs: t_firstblock is tracking AGs not blocks

The tp->t_firstblock field is now raelly tracking the highest AG we
have locked, not the block number of the highest allocation we've
made. It's purpose is to prevent AGF locking deadlocks, so rename it
to "highest AG" and simplify the implementation to just track the
agno rather than a fsbno.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

10 files changed, 21 insertions, 23 deletions

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index ffe6345bfafc..974b23abca60 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -3169,8 +3169,8 @@ xfs_alloc_vextent(
 	mp = args->mp;
 	type = args->otype = args->type;
 	args->agbno = NULLAGBLOCK;
-	if (args->tp->t_firstblock != NULLFSBLOCK)
-		minimum_agno = XFS_FSB_TO_AGNO(mp, args->tp->t_firstblock);
+	if (args->tp->t_highest_agno != NULLAGNUMBER)
+		minimum_agno = args->tp->t_highest_agno;
 	/*
 	 * Just fix this up, for the case where the last a.g. is shorter
 	 * (or there's only one a.g.) and the caller couldn't easily figure
@@ -3375,11 +3375,9 @@ xfs_alloc_vextent(
 	 * deadlocks.
 	 */
 	if (args->agbp &&
-	    (args->tp->t_firstblock == NULLFSBLOCK ||
-	     args->pag->pag_agno > minimum_agno)) {
-		args->tp->t_firstblock = XFS_AGB_TO_FSB(mp,
-					args->pag->pag_agno, 0);
-	}
+	    (args->tp->t_highest_agno == NULLAGNUMBER ||
+	     args->pag->pag_agno > minimum_agno))
+		args->tp->t_highest_agno = args->pag->pag_agno;
 	xfs_perag_put(args->pag);
 	return 0;
 error0:
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 31a0738d017e..504fd69fe2c6 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -4192,7 +4192,7 @@ xfs_bmapi_minleft(
 {
 	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, fork);
 
-	if (tp && tp->t_firstblock != NULLFSBLOCK)
+	if (tp && tp->t_highest_agno != NULLAGNUMBER)
 		return 0;
 	if (ifp->if_format != XFS_DINODE_FMT_BTREE)
 		return 1;
@@ -6079,7 +6079,7 @@ xfs_bmap_finish_one(
 	struct xfs_bmbt_irec		*bmap = &bi->bi_bmap;
 	int				error = 0;
 
-	ASSERT(tp->t_firstblock == NULLFSBLOCK);
+	ASSERT(tp->t_highest_agno == NULLAGNUMBER);
 
 	trace_xfs_bmap_deferred(tp->t_mountp,
 			XFS_FSB_TO_AGNO(tp->t_mountp, bmap->br_startblock),
diff --git a/fs/xfs/libxfs/xfs_bmap_btree.c b/fs/xfs/libxfs/xfs_bmap_btree.c
index 76a0f0d260a4..afd9b2d962a3 100644
--- a/fs/xfs/libxfs/xfs_bmap_btree.c
+++ b/fs/xfs/libxfs/xfs_bmap_btree.c
@@ -184,11 +184,11 @@ xfs_bmbt_update_cursor(
 	struct xfs_btree_cur	*src,
 	struct xfs_btree_cur	*dst)
 {
-	ASSERT((dst->bc_tp->t_firstblock != NULLFSBLOCK) ||
+	ASSERT((dst->bc_tp->t_highest_agno != NULLAGNUMBER) ||
 	       (dst->bc_ino.ip->i_diflags & XFS_DIFLAG_REALTIME));
 
 	dst->bc_ino.allocated += src->bc_ino.allocated;
-	dst->bc_tp->t_firstblock = src->bc_tp->t_firstblock;
+	dst->bc_tp->t_highest_agno = src->bc_tp->t_highest_agno;
 
 	src->bc_ino.allocated = 0;
 }
@@ -218,7 +218,7 @@ xfs_bmbt_alloc_block(
 	 * we have to ensure that we attempt to locate the entire set of bmbt
 	 * allocations in the same AG, as xfs_bmapi_write() would have reserved.
 	 */
-	if (cur->bc_tp->t_firstblock == NULLFSBLOCK)
+	if (cur->bc_tp->t_highest_agno == NULLAGNUMBER)
 		args.minleft = xfs_bmapi_minleft(cur->bc_tp, cur->bc_ino.ip,
 					cur->bc_ino.whichfork);
 
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index da8c769887fd..c4649cc624e1 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -2943,7 +2943,7 @@ xfs_btree_split(
 	DECLARE_COMPLETION_ONSTACK(done);
 
 	if (cur->bc_btnum != XFS_BTNUM_BMAP ||
-	    cur->bc_tp->t_firstblock == NULLFSBLOCK)
+	    cur->bc_tp->t_highest_agno == NULLAGNUMBER)
 		return __xfs_btree_split(cur, level, ptrp, key, curp, stat);
 
 	args.cur = cur;
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 867645b74d88..a09dd2606479 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1410,7 +1410,7 @@ xfs_swap_extent_rmap(
 
 		/* Unmap the old blocks in the source file. */
 		while (tirec.br_blockcount) {
-			ASSERT(tp->t_firstblock == NULLFSBLOCK);
+			ASSERT(tp->t_highest_agno == NULLAGNUMBER);
 			trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec);
 
 			/* Read extent from the source file */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index d354ea2b74f9..dbe274b8065d 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1367,7 +1367,7 @@ xfs_itruncate_extents_flags(
 
 	unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1;
 	while (unmap_len > 0) {
-		ASSERT(tp->t_firstblock == NULLFSBLOCK);
+		ASSERT(tp->t_highest_agno == NULLAGNUMBER);
 		error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len,
 				flags, XFS_ITRUNC_MAX_EXTENTS);
 		if (error)
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 5535778a98f9..57bf59ff4854 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -610,7 +610,7 @@ xfs_reflink_cancel_cow_blocks(
 			if (error)
 				break;
 		} else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) {
-			ASSERT((*tpp)->t_firstblock == NULLFSBLOCK);
+			ASSERT((*tpp)->t_highest_agno == NULLAGNUMBER);
 
 			/* Free the CoW orphan record. */
 			xfs_refcount_free_cow_extent(*tpp, del.br_startblock,
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index adddaeb44a56..2ac98d8ddbfd 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -1801,7 +1801,7 @@ DECLARE_EVENT_CLASS(xfs_alloc_class,
 		__field(char, wasfromfl)
 		__field(int, resv)
 		__field(int, datatype)
-		__field(xfs_fsblock_t, firstblock)
+		__field(xfs_agnumber_t, highest_agno)
 	),
 	TP_fast_assign(
 		__entry->dev = args->mp->m_super->s_dev;
@@ -1822,12 +1822,12 @@ DECLARE_EVENT_CLASS(xfs_alloc_class,
 		__entry->wasfromfl = args->wasfromfl;
 		__entry->resv = args->resv;
 		__entry->datatype = args->datatype;
-		__entry->firstblock = args->tp->t_firstblock;
+		__entry->highest_agno = args->tp->t_highest_agno;
 	),
 	TP_printk("dev %d:%d agno 0x%x agbno 0x%x minlen %u maxlen %u mod %u "
 		  "prod %u minleft %u total %u alignment %u minalignslop %u "
 		  "len %u type %s otype %s wasdel %d wasfromfl %d resv %d "
-		  "datatype 0x%x firstblock 0x%llx",
+		  "datatype 0x%x highest_agno 0x%x",
 		  MAJOR(__entry->dev), MINOR(__entry->dev),
 		  __entry->agno,
 		  __entry->agbno,
@@ -1846,7 +1846,7 @@ DECLARE_EVENT_CLASS(xfs_alloc_class,
 		  __entry->wasfromfl,
 		  __entry->resv,
 		  __entry->datatype,
-		  (unsigned long long)__entry->firstblock)
+		  __entry->highest_agno)
 )
 
 #define DEFINE_ALLOC_EVENT(name) \
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index 7bd16fbff534..53ab544e4c2c 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -102,7 +102,7 @@ xfs_trans_dup(
 	INIT_LIST_HEAD(&ntp->t_items);
 	INIT_LIST_HEAD(&ntp->t_busy);
 	INIT_LIST_HEAD(&ntp->t_dfops);
-	ntp->t_firstblock = NULLFSBLOCK;
+	ntp->t_highest_agno = NULLAGNUMBER;
 
 	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
 	ASSERT(tp->t_ticket != NULL);
@@ -278,7 +278,7 @@ retry:
 	INIT_LIST_HEAD(&tp->t_items);
 	INIT_LIST_HEAD(&tp->t_busy);
 	INIT_LIST_HEAD(&tp->t_dfops);
-	tp->t_firstblock = NULLFSBLOCK;
+	tp->t_highest_agno = NULLAGNUMBER;
 
 	error = xfs_trans_reserve(tp, resp, blocks, rtextents);
 	if (error == -ENOSPC && want_retry) {
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 55819785941c..6e3646d524ce 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -132,7 +132,7 @@ typedef struct xfs_trans {
 	unsigned int		t_rtx_res;	/* # of rt extents resvd */
 	unsigned int		t_rtx_res_used;	/* # of resvd rt extents used */
 	unsigned int		t_flags;	/* misc flags */
-	xfs_fsblock_t		t_firstblock;	/* first block allocated */
+	xfs_agnumber_t		t_highest_agno;	/* highest AGF locked */
 	struct xlog_ticket	*t_ticket;	/* log mgr ticket */
 	struct xfs_mount	*t_mountp;	/* ptr to fs mount struct */
 	struct xfs_dquot_acct   *t_dqinfo;	/* acctg info for dquots */