From 5f9268ca53aca992106d74edde3e7cf6c1be60a0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 20 Oct 2016 15:53:32 +1100 Subject: [PATCH] xfs: don't bother looking at the refcount tree for reads There is no need to trim an extent into a shared or non-shared one, or report any flags for plain old reads. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- fs/xfs/xfs_iomap.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index d907eb9f8ef3..1dabf2eb136a 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -996,11 +996,14 @@ xfs_file_iomap_begin( return error; } - /* Trim the mapping to the nearest shared extent boundary. */ - error = xfs_reflink_trim_around_shared(ip, &imap, &shared, &trimmed); - if (error) { - xfs_iunlock(ip, lockmode); - return error; + if (flags & (IOMAP_WRITE | IOMAP_ZERO | IOMAP_REPORT)) { + /* Trim the mapping to the nearest shared extent boundary. */ + error = xfs_reflink_trim_around_shared(ip, &imap, &shared, + &trimmed); + if (error) { + xfs_iunlock(ip, lockmode); + return error; + } } if ((flags & IOMAP_WRITE) && imap_needs_alloc(inode, &imap, nimaps)) { -- 2.20.1