cache=none means to bypass host cache. So we can't remove O_DIRECT flag in unconditionally in update_open_flags();
Signed-off-by: Catherine Ho <catherine.h...@gmail.com> --- v2: Fix to keep flags unchanged if cache=none, otherwise changed the file without O_DIRECT incorrectly. tools/virtiofsd/passthrough_ll.c | 14 ++++++++------ 1 files changed, 8 insertions(+), 6 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 4c35c95..59e64dd 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -1677,7 +1677,8 @@ static void lo_releasedir(fuse_req_t req, fuse_ino_t ino, fuse_reply_err(req, 0); } -static void update_open_flags(int writeback, struct fuse_file_info *fi) +static void update_open_flags(int writeback, int cache_mode, + struct fuse_file_info *fi) { /* * With writeback cache, kernel may send read requests even @@ -1702,10 +1703,11 @@ static void update_open_flags(int writeback, struct fuse_file_info *fi) /* * O_DIRECT in guest should not necessarily mean bypassing page - * cache on host as well. If somebody needs that behavior, it - * probably should be a configuration knob in daemon. + * cache on host as well. If cache=none, keep the flag unchanged */ - fi->flags &= ~O_DIRECT; + if (cache_mode != CACHE_NONE) { + fi->flags &= ~O_DIRECT; + } } static void lo_create(fuse_req_t req, fuse_ino_t parent, const char *name, @@ -1737,7 +1739,7 @@ static void lo_create(fuse_req_t req, fuse_ino_t parent, const char *name, goto out; } - update_open_flags(lo->writeback, fi); + update_open_flags(lo->writeback, lo->cache, fi); fd = openat(parent_inode->fd, name, (fi->flags | O_CREAT) & ~O_NOFOLLOW, mode); @@ -1947,7 +1949,7 @@ static void lo_open(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi) fuse_log(FUSE_LOG_DEBUG, "lo_open(ino=%" PRIu64 ", flags=%d)\n", ino, fi->flags); - update_open_flags(lo->writeback, fi); + update_open_flags(lo->writeback, lo->cache, fi); sprintf(buf, "%i", lo_fd(req, ino)); fd = openat(lo->proc_self_fd, buf, fi->flags & ~O_NOFOLLOW); -- 1.7.1