xfs: split xfs_trim_rtdev_extents

Split xfs_trim_rtdev_extents into two parts to prepare for reusing the
main validation also for RT group aware file systems.

Use the fully features xfs_daddr_to_rtb helper to convert from a daddr
to a xfs_rtblock_t to prepare for segmented addressing in RT groups.

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

Author: Christoph Hellwig

fs/xfs/xfs_discard.c

@@ -21,6 +21,7 @@
 #include "xfs_ag.h"
 #include "xfs_health.h"
 #include "xfs_rtbitmap.h"
+#include "xfs_rtgroup.h"
 
 /*
  * Notes on an efficient, low latency fstrim algorithm
@@ -548,44 +549,23 @@ xfs_trim_gather_rtextent(
 }
 
 static int
-xfs_trim_rtdev_extents(
+xfs_trim_rtextents(
 	struct xfs_mount	*mp,
-	xfs_daddr_t		start,
-	xfs_daddr_t		end,
+	xfs_rtxnum_t		low,
+	xfs_rtxnum_t		high,
 	xfs_daddr_t		minlen)
 {
 	struct xfs_trim_rtdev	tr = {
 		.minlen_fsb	= XFS_BB_TO_FSB(mp, minlen),
+		.extent_list	= LIST_HEAD_INIT(tr.extent_list),
 	};
-	xfs_rtxnum_t		low, high;
 	struct xfs_trans	*tp;
-	xfs_daddr_t		rtdev_daddr;
 	int			error;
 
-	INIT_LIST_HEAD(&tr.extent_list);
-
-	/* Shift the start and end downwards to match the rt device. */
-	rtdev_daddr = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
-	if (start > rtdev_daddr)
-		start -= rtdev_daddr;
-	else
-		start = 0;
-
-	if (end <= rtdev_daddr)
-		return 0;
-	end -= rtdev_daddr;
-
 	error = xfs_trans_alloc_empty(mp, &tp);
 	if (error)
 		return error;
 
-	end = min_t(xfs_daddr_t, end,
-			XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks) - 1);
-
-	/* Convert the rt blocks to rt extents */
-	low = xfs_rtb_to_rtxup(mp, XFS_BB_TO_FSB(mp, start));
-	high = xfs_rtb_to_rtx(mp, XFS_BB_TO_FSBT(mp, end));
-
 	/*
 	 * Walk the free ranges between low and high.  The query_range function
 	 * trims the extents returned.
@@ -620,6 +600,33 @@ xfs_trim_rtdev_extents(
 	xfs_trans_cancel(tp);
 	return error;
 }
+
+static int
+xfs_trim_rtdev_extents(
+	struct xfs_mount	*mp,
+	xfs_daddr_t		start,
+	xfs_daddr_t		end,
+	xfs_daddr_t		minlen)
+{
+	xfs_rtblock_t		start_rtbno, end_rtbno;
+	xfs_rtxnum_t		start_rtx, end_rtx;
+
+	/* Shift the start and end downwards to match the rt device. */
+	start_rtbno = xfs_daddr_to_rtb(mp, start);
+	if (start_rtbno > mp->m_sb.sb_dblocks)
+		start_rtbno -= mp->m_sb.sb_dblocks;
+	else
+		start_rtbno = 0;
+	start_rtx = xfs_rtb_to_rtx(mp, start_rtbno);
+
+	end_rtbno = xfs_daddr_to_rtb(mp, end);
+	if (end_rtbno <= mp->m_sb.sb_dblocks)
+		return 0;
+	end_rtbno -= mp->m_sb.sb_dblocks;
+	end_rtx = xfs_rtb_to_rtx(mp, end_rtbno + mp->m_sb.sb_rextsize - 1);
+
+	return xfs_trim_rtextents(mp, start_rtx, end_rtx, minlen);
+}
 #else
 # define xfs_trim_rtdev_extents(...)	(-EOPNOTSUPP)
 #endif /* CONFIG_XFS_RT */