From 689e11c84b15866619e7582486acacaf79d7e3e2 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 14 May 2018 06:34:31 -0700 Subject: xfs: superblock scrub should use short-lived buffers Secondary superblocks are rarely used, so create a helper to read a given non-primary AG's superblock and ensure that it won't stick around hogging memory. Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster --- fs/xfs/libxfs/xfs_sb.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'fs/xfs/libxfs/xfs_sb.c') diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c index d9b94bd5f689..d9bef41a3f26 100644 --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -972,3 +972,25 @@ xfs_fs_geometry( return 0; } + +/* Read a secondary superblock. */ +int +xfs_sb_read_secondary( + struct xfs_mount *mp, + struct xfs_trans *tp, + xfs_agnumber_t agno, + struct xfs_buf **bpp) +{ + struct xfs_buf *bp; + int error; + + ASSERT(agno != 0 && agno != NULLAGNUMBER); + error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, + XFS_AG_DADDR(mp, agno, XFS_SB_BLOCK(mp)), + XFS_FSS_TO_BB(mp, 1), 0, &bp, &xfs_sb_buf_ops); + if (error) + return error; + xfs_buf_set_ref(bp, XFS_SSB_REF); + *bpp = bp; + return 0; +} -- cgit v1.2.3