From e4648309b85a78f8c787457832269a8712a8673e Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 23 Oct 2019 14:26:37 +0200 Subject: [PATCH] fuse: truncate pending writes on O_TRUNC Make sure cached writes are not reordered around open(..., O_TRUNC), with the obvious wrong results. Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on") Cc: # v3.15+ Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 0f0225686aee..6edf949b9139 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -217,7 +217,7 @@ int fuse_open_common(struct inode *inode, struct file *file, bool isdir) { struct fuse_conn *fc = get_fuse_conn(inode); int err; - bool lock_inode = (file->f_flags & O_TRUNC) && + bool is_wb_truncate = (file->f_flags & O_TRUNC) && fc->atomic_o_trunc && fc->writeback_cache; @@ -225,16 +225,20 @@ int fuse_open_common(struct inode *inode, struct file *file, bool isdir) if (err) return err; - if (lock_inode) + if (is_wb_truncate) { inode_lock(inode); + fuse_set_nowrite(inode); + } err = fuse_do_open(fc, get_node_id(inode), file, isdir); if (!err) fuse_finish_open(inode, file); - if (lock_inode) + if (is_wb_truncate) { + fuse_release_nowrite(inode); inode_unlock(inode); + } return err; }