[PATCH 14/19] fuse2fs: add strictatime/lazytime mount options

Darrick J. Wong
2025-08-21T01:19:21Z

In iomap mode, we can support the strictatime/lazytime mount options.
Add them to fuse2fs.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
---
misc/fuse2fs.c | 28 ++++++++++++++++++++++++++++
misc/fuse4fs.c | 28 ++++++++++++++++++++++++++++
2 files changed, 56 insertions(+)

diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c
index 291416afb93d6c..9ac9077f3508f7 100644
--- a/misc/fuse2fs.c
+++ b/misc/fuse2fs.c
@@ -267,6 +267,7 @@ struct fuse2fs {
uint8_t dirsync;
uint8_t unmount_in_destroy;
uint8_t noblkdev;
+ uint8_t iomap_passthrough_options;

enum fuse2fs_opstate opstate;
int logfd;
@@ -1422,6 +1423,8 @@ static void fuse2fs_iomap_enable(struct fuse_conn_info *conn,
if (!fuse2fs_iomap_enabled(ff)) {
if (ff->iomap_want == FT_ENABLE)
err_printf(ff, "%s\n", _("Could not enable iomap."));
+ if (ff->iomap_passthrough_options)
+ err_printf(ff, "%s\n", _("Some mount options require iomap."));
return;
}
}
@@ -6394,6 +6397,7 @@ enum {
FUSE2FS_ERRORS_BEHAVIOR,
#ifdef HAVE_FUSE_IOMAP
FUSE2FS_IOMAP,
+ FUSE2FS_IOMAP_PASSTHROUGH,
#endif
};

@@ -6420,6 +6424,17 @@ static struct fuse_opt fuse2fs_opts[] = {
#endif
FUSE2FS_OPT("noblkdev", noblkdev, 1),

+#ifdef HAVE_FUSE_IOMAP
+#ifdef MS_LAZYTIME
+ FUSE_OPT_KEY("lazytime", FUSE2FS_IOMAP_PASSTHROUGH),
+ FUSE_OPT_KEY("nolazytime", FUSE2FS_IOMAP_PASSTHROUGH),
+#endif
+#ifdef MS_STRICTATIME
+ FUSE_OPT_KEY("strictatime", FUSE2FS_IOMAP_PASSTHROUGH),
+ FUSE_OPT_KEY("nostrictatime", FUSE2FS_IOMAP_PASSTHROUGH),
+#endif
+#endif
+
FUSE_OPT_KEY("user_xattr", FUSE2FS_IGNORED),
FUSE_OPT_KEY("noblock_validity", FUSE2FS_IGNORED),
FUSE_OPT_KEY("nodelalloc", FUSE2FS_IGNORED),
@@ -6446,6 +6461,12 @@ static int fuse2fs_opt_proc(void *data, const char *arg,
struct fuse2fs *ff = data;

switch (key) {
+#ifdef HAVE_FUSE_IOMAP
+ case FUSE2FS_IOMAP_PASSTHROUGH:
+ ff->iomap_passthrough_options = 1;
+ /* pass through to libfuse */
+ return 1;
+#endif
case FUSE2FS_DIRSYNC:
ff->dirsync = 1;
/* pass through to libfuse */
@@ -6735,6 +6756,13 @@ int main(int argc, char *argv[])
fctx.unmount_in_destroy = 1;
}

+ if (fctx.iomap_passthrough_options && !iomap_detected) {
+ err_printf(&fctx, "%s\n",
+ _("Some mount options require iomap."));
+ ret |= 1;
+ goto out;
+ }
+
if (!fctx.cache_size)
fctx.cache_size = default_cache_size();
if (fctx.cache_size) {
diff --git a/misc/fuse4fs.c b/misc/fuse4fs.c
index 37a7ab3a3718e4..1050238c88632d 100644
--- a/misc/fuse4fs.c
+++ b/misc/fuse4fs.c
@@ -262,6 +262,7 @@ struct fuse4fs {
uint8_t dirsync;
uint8_t unmount_in_destroy;
uint8_t noblkdev;
+ uint8_t iomap_passthrough_options;

enum fuse4fs_opstate opstate;
int logfd;
@@ -1603,6 +1604,8 @@ static void fuse4fs_iomap_enable(struct fuse_conn_info *conn,
if (!fuse4fs_iomap_enabled(ff)) {
if (ff->iomap_want == FT_ENABLE)
err_printf(ff, "%s\n", _("Could not enable iomap."));
+ if (ff->iomap_passthrough_options)
+ err_printf(ff, "%s\n", _("Some mount options require iomap."));
return;
}
}
@@ -6697,6 +6700,7 @@ enum {
FUSE4FS_ERRORS_BEHAVIOR,
#ifdef HAVE_FUSE_IOMAP
FUSE4FS_IOMAP,
+ FUSE4FS_IOMAP_PASSTHROUGH,
#endif
};

@@ -6723,6 +6727,17 @@ static struct fuse_opt fuse4fs_opts[] = {
#endif
FUSE4FS_OPT("noblkdev", noblkdev, 1),

+#ifdef HAVE_FUSE_IOMAP
+#ifdef MS_LAZYTIME
+ FUSE_OPT_KEY("lazytime", FUSE4FS_IOMAP_PASSTHROUGH),
+ FUSE_OPT_KEY("nolazytime", FUSE4FS_IOMAP_PASSTHROUGH),
+#endif
+#ifdef MS_STRICTATIME
+ FUSE_OPT_KEY("strictatime", FUSE4FS_IOMAP_PASSTHROUGH),
+ FUSE_OPT_KEY("nostrictatime", FUSE4FS_IOMAP_PASSTHROUGH),
+#endif
+#endif
+
FUSE_OPT_KEY("user_xattr", FUSE4FS_IGNORED),
FUSE_OPT_KEY("noblock_validity", FUSE4FS_IGNORED),
FUSE_OPT_KEY("nodelalloc", FUSE4FS_IGNORED),
@@ -6749,6 +6764,12 @@ static int fuse4fs_opt_proc(void *data, const char *arg,
struct fuse4fs *ff = data;

switch (key) {
+#ifdef HAVE_FUSE_IOMAP
+ case FUSE4FS_IOMAP_PASSTHROUGH:
+ ff->iomap_passthrough_options = 1;
+ /* pass through to libfuse */
+ return 1;
+#endif
case FUSE4FS_DIRSYNC:
ff->dirsync = 1;
/* pass through to libfuse */
@@ -7137,6 +7158,13 @@ int main(int argc, char *argv[])
fctx.unmount_in_destroy = 1;
}

+ if (fctx.iomap_passthrough_options && !iomap_detected) {
+ err_printf(&fctx, "%s\n",
+ _("Some mount options require iomap."));
+ ret |= 1;
+ goto out;
+ }
+
if (!fctx.cache_size)
fctx.cache_size = default_cache_size();
if (fctx.cache_size) {