From 2c334e12f957cd8c6bb66b4aa3f79848b7c33cab Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <darrick.wong@oracle.com>
Date: Mon, 26 Oct 2020 15:19:38 -0700
Subject: [PATCH] xfs: set xefi_discard when creating a deferred agfl free log
 intent item
Git-commit: 2c334e12f957cd8c6bb66b4aa3f79848b7c33cab
Patch-mainline: v5.10-rc3
References: git-fixes

Make sure that we actually initialize xefi_discard when we're scheduling
a deferred free of an AGFL block.  This was (eventually) found by the
UBSAN while I was banging on realtime rmap problems, but it exists in
the upstream codebase.  While we're at it, rearrange the structure to
reduce the struct size from 64 to 56 bytes.

Fixes: fcb762f5de2e ("xfs: add bmapi nodiscard flag")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Acked-by: Anthony Iliopoulos <ailiop@suse.com>

---
 fs/xfs/libxfs/xfs_alloc.c | 1 +
 fs/xfs/libxfs/xfs_bmap.h  | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 852b536551b5..15640015be9d 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -2467,6 +2467,7 @@ xfs_defer_agfl_block(
 	new->xefi_startblock = XFS_AGB_TO_FSB(mp, agno, agbno);
 	new->xefi_blockcount = 1;
 	new->xefi_oinfo = *oinfo;
+	new->xefi_skip_discard = false;
 
 	trace_xfs_agfl_free_defer(mp, agno, 0, agbno, 1);
 
diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h
index e1bd484e5548..6747e97a7949 100644
--- a/fs/xfs/libxfs/xfs_bmap.h
+++ b/fs/xfs/libxfs/xfs_bmap.h
@@ -52,9 +52,9 @@ struct xfs_extent_free_item
 {
 	xfs_fsblock_t		xefi_startblock;/* starting fs block number */
 	xfs_extlen_t		xefi_blockcount;/* number of blocks in extent */
+	bool			xefi_skip_discard;
 	struct list_head	xefi_list;
 	struct xfs_owner_info	xefi_oinfo;	/* extent owner */
-	bool			xefi_skip_discard;
 };
 
 #define	XFS_BMAP_MAX_NMAP	4
-- 
2.29.1