Add no_rofd_flush mount option

To disable flush for read-only fd.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>

diff --git a/include/fuse.h b/include/fuse.h
index a273b15b9161d5c1c31cdfc15fe4226d2ef38d68..91486882824016602fe8c1d289986f2fabc841d1 100644 (file)
--- a/include/fuse.h
+++ b/include/fuse.h
@@ -247,6 +247,14 @@ struct fuse_config {
         */
        int auto_cache;
 
+       /**
+        * By default, fuse waits for all pending writes to complete
+        * and calls the FLUSH operation on close(2) of every fuse fd.
+        * With this option, wait and FLUSH are not done for read-only
+        * fuse fd, similar to the behavior of NFS/SMB clients.
+        */
+       int no_rofd_flush;
+
        /**
         * The timeout in seconds for which file attributes are cached
         * for the purpose of checking if auto_cache should flush the

diff --git a/lib/fuse.c b/lib/fuse.c
index a95d7c12d733f193d2c773e3f580d6e11f378a8c..cc5bb14d0e82669bf9f80913b17e6ef85ff2b2fe 100644 (file)
--- a/lib/fuse.c
+++ b/lib/fuse.c
@@ -3272,6 +3272,10 @@ static void fuse_lib_open(fuse_req_t req, fuse_ino_t ino,
 
                        if (f->conf.auto_cache)
                                open_auto_cache(f, ino, path, fi);
+
+                       if (f->conf.no_rofd_flush &&
+                           (fi->flags & O_ACCMODE) == O_RDONLY)
+                               fi->noflush = 1;
                }
                fuse_finish_interrupt(f, req, &d);
        }
@@ -4653,6 +4657,7 @@ static const struct fuse_opt fuse_lib_opts[] = {
        FUSE_LIB_OPT("kernel_cache",          kernel_cache, 1),
        FUSE_LIB_OPT("auto_cache",            auto_cache, 1),
        FUSE_LIB_OPT("noauto_cache",          auto_cache, 0),
+       FUSE_LIB_OPT("no_rofd_flush",         no_rofd_flush, 1),
        FUSE_LIB_OPT("umask=",                set_mode, 1),
        FUSE_LIB_OPT("umask=%o",              umask, 0),
        FUSE_LIB_OPT("uid=",                  set_uid, 1),
@@ -4705,6 +4710,7 @@ void fuse_lib_help(struct fuse_args *args)
        printf(
 "    -o kernel_cache        cache files in kernel\n"
 "    -o [no]auto_cache      enable caching based on modification times (off)\n"
+"    -o no_rofd_flush       disable flushing of read-only fd on close (off)\n"
 "    -o umask=M             set file permissions (octal)\n"
 "    -o uid=N               set file owner\n"
 "    -o gid=N               set file group\n"