xfs: port the perag discard code to handle generic groups

Port xfs_discard_extents and its tracepoints to handle generic groups
instead of just perags.  This is needed to enable busy extent tracking
for rtgroups.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Author: Darrick J. Wong

fs/xfs/xfs_discard.c

@@ -101,6 +101,24 @@ xfs_discard_endio(
 	bio_put(bio);
 }
 
+static inline struct block_device *
+xfs_group_bdev(
+	const struct xfs_group	*xg)
+{
+	struct xfs_mount	*mp = xg->xg_mount;
+
+	switch (xg->xg_type) {
+	case XG_TYPE_AG:
+		return mp->m_ddev_targp->bt_bdev;
+	case XG_TYPE_RTG:
+		return mp->m_rtdev_targp->bt_bdev;
+	default:
+		ASSERT(0);
+		break;
+	}
+	return NULL;
+}
+
 /*
  * Walk the discard list and issue discards on all the busy extents in the
  * list. We plug and chain the bios so that we only need a single completion
@@ -118,12 +136,11 @@ xfs_discard_extents(
 
 	blk_start_plug(&plug);
 	list_for_each_entry(busyp, &extents->extent_list, list) {
-		struct xfs_perag	*pag = to_perag(busyp->group);
-
-		trace_xfs_discard_extent(pag, busyp->bno, busyp->length);
+		trace_xfs_discard_extent(busyp->group, busyp->bno,
+				busyp->length);
 
-		error = __blkdev_issue_discard(mp->m_ddev_targp->bt_bdev,
-				xfs_agbno_to_daddr(pag, busyp->bno),
+		error = __blkdev_issue_discard(xfs_group_bdev(busyp->group),
+				xfs_gbno_to_daddr(busyp->group, busyp->bno),
 				XFS_FSB_TO_BB(mp, busyp->length),
 				GFP_KERNEL, &bio);
 		if (error && error != -EOPNOTSUPP) {
@@ -241,11 +258,11 @@ xfs_trim_gather_extents(
 		 * overlapping ranges for now.
 		 */
 		if (fbno + flen < tcur->start) {
-			trace_xfs_discard_exclude(pag, fbno, flen);
+			trace_xfs_discard_exclude(pag_group(pag), fbno, flen);
 			goto next_extent;
 		}
 		if (fbno > tcur->end) {
-			trace_xfs_discard_exclude(pag, fbno, flen);
+			trace_xfs_discard_exclude(pag_group(pag), fbno, flen);
 			if (tcur->by_bno) {
 				tcur->count = 0;
 				break;
@@ -263,7 +280,7 @@ xfs_trim_gather_extents(
 
 		/* Too small?  Give up. */
 		if (flen < tcur->minlen) {
-			trace_xfs_discard_toosmall(pag, fbno, flen);
+			trace_xfs_discard_toosmall(pag_group(pag), fbno, flen);
 			if (tcur->by_bno)
 				goto next_extent;
 			tcur->count = 0;
@@ -275,7 +292,7 @@ xfs_trim_gather_extents(
 		 * discard and try again the next time.
 		 */
 		if (xfs_extent_busy_search(pag_group(pag), fbno, flen)) {
-			trace_xfs_discard_busy(pag, fbno, flen);
+			trace_xfs_discard_busy(pag_group(pag), fbno, flen);
 			goto next_extent;
 		}
 

fs/xfs/xfs_trace.h

@@ -2475,33 +2475,36 @@ DEFINE_LOG_RECOVER_ICREATE_ITEM(xfs_log_recover_icreate_cancel);
 DEFINE_LOG_RECOVER_ICREATE_ITEM(xfs_log_recover_icreate_recover);
 
 DECLARE_EVENT_CLASS(xfs_discard_class,
-	TP_PROTO(const struct xfs_perag *pag, xfs_agblock_t agbno,
+	TP_PROTO(const struct xfs_group *xg, xfs_agblock_t agbno,
 		 xfs_extlen_t len),
-	TP_ARGS(pag, agbno, len),
+	TP_ARGS(xg, agbno, len),
 	TP_STRUCT__entry(
 		__field(dev_t, dev)
+		__field(enum xfs_group_type, type)
 		__field(xfs_agnumber_t, agno)
 		__field(xfs_agblock_t, agbno)
 		__field(xfs_extlen_t, len)
 	),
 	TP_fast_assign(
-		__entry->dev = pag_mount(pag)->m_super->s_dev;
-		__entry->agno = pag_agno(pag);
+		__entry->dev = xg->xg_mount->m_super->s_dev;
+		__entry->type = xg->xg_type;
+		__entry->agno = xg->xg_gno;
 		__entry->agbno = agbno;
 		__entry->len = len;
 	),
-	TP_printk("dev %d:%d agno 0x%x agbno 0x%x fsbcount 0x%x",
+	TP_printk("dev %d:%d %sno 0x%x gbno 0x%x fsbcount 0x%x",
 		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __print_symbolic(__entry->type, XG_TYPE_STRINGS),
 		  __entry->agno,
 		  __entry->agbno,
 		  __entry->len)
 )
 
 #define DEFINE_DISCARD_EVENT(name) \
 DEFINE_EVENT(xfs_discard_class, name, \
-	TP_PROTO(const struct xfs_perag *pag, xfs_agblock_t agbno, \
-		xfs_extlen_t len), \
-	TP_ARGS(pag, agbno, len))
+	TP_PROTO(const struct xfs_group *xg, xfs_agblock_t agbno, \
+		 xfs_extlen_t len), \
+	TP_ARGS(xg, agbno, len))
 DEFINE_DISCARD_EVENT(xfs_discard_extent);
 DEFINE_DISCARD_EVENT(xfs_discard_toosmall);
 DEFINE_DISCARD_EVENT(xfs_discard_exclude);