From a2bc92362941006830afa3dfad6caec1f99acbf5 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 28 May 2019 13:22:50 +0200 Subject: [PATCH] fuse: fix copy_file_range() in the writeback case Prior to sending COPY_FILE_RANGE to userspace filesystem, we must flush all dirty pages in both the source and destination files. This patch adds the missing flush of the source file. Tested on libfuse-3.5.0 with: libfuse/example/passthrough_ll /mnt/fuse/ -o writeback libfuse/test/test_syscalls /mnt/fuse/tmp/test Fixes: 88bc7d5097a1 ("fuse: add support for copy_file_range()") Cc: # v4.20 Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index c1064866c402..4141d94de4ff 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -3110,6 +3110,7 @@ static ssize_t fuse_copy_file_range(struct file *file_in, loff_t pos_in, { struct fuse_file *ff_in = file_in->private_data; struct fuse_file *ff_out = file_out->private_data; + struct inode *inode_in = file_inode(file_in); struct inode *inode_out = file_inode(file_out); struct fuse_inode *fi_out = get_fuse_inode(inode_out); struct fuse_conn *fc = ff_in->fc; @@ -3133,6 +3134,17 @@ static ssize_t fuse_copy_file_range(struct file *file_in, loff_t pos_in, if (fc->no_copy_file_range) return -EOPNOTSUPP; + if (fc->writeback_cache) { + inode_lock(inode_in); + err = filemap_write_and_wait_range(inode_in->i_mapping, + pos_in, pos_in + len); + if (!err) + fuse_sync_writes(inode_in); + inode_unlock(inode_in); + if (err) + return err; + } + inode_lock(inode_out); if (fc->writeback_cache) {