From f74409656ae67aa6fe735c09d9edef9dc5a50d6c Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 5 Sep 2025 15:25:34 -0700 Subject: [PATCH] fuse2fs: work around EBUSY discard returns from dm-thinp generic/500 has this interesting failure mode when fuse2fs is running in fuseblk mode: --- /run/fstests/bin/tests/generic/500.out 2025-07-15 14:45:15.092576090 -0700 +++ /var/tmp/fstests/generic/500.out.bad 2025-09-05 15:09:35.211499883 -0700 @@ -1,2 +1,22 @@ QA output created by 500 +fstrim: /opt: FITRIM ioctl failed: Device or resource busy Apparently you can overwhelm dm-thinp with a large number of discard requests, at which point it starts returning EBUSY. This is unexpected behavior but let's mask that off because discard is advisory anyways. Signed-off-by: "Darrick J. Wong" --- misc/fuse2fs.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c index b8db298c..68644664 100644 --- a/misc/fuse2fs.c +++ b/misc/fuse2fs.c @@ -4038,6 +4038,14 @@ static int ioctl_fitrim(struct fuse2fs *ff, struct fuse2fs_file_handle *fh, if (b - start >= minlen) { err = io_channel_discard(fs->io, start, b - start); + if (err == EBUSY) { + /* + * Apparently dm-thinp can return EBUSY when + * it's too busy deallocating thinp units to + * deallocate more. Swallow these errors. + */ + err = 0; + } if (err) return translate_error(fs, fh->ino, err); cleared += b - start; -- 2.47.3