On Sat, Sep 05 2026, Amir Goldstein wrote: > On Fri, Sep 4, 2026 at 12:38 PM Luis Henriques <[email protected]> wrote: >> >> This patch adds a simple test that allows to verify that, when resolving a >> symlink, user-space is called only the first time when caching is enabled >> or, if caching is disabled, every time the symlink resolution is requested. >> >> Signed-off-by: Luis Henriques <[email protected]> >> --- >> .../selftests/filesystems/fuse/.gitignore | 1 + >> .../selftests/filesystems/fuse/Makefile | 2 + >> .../fuse/fuse_symlink_cache_test.c | 167 ++++++++++++++++++ >> 3 files changed, 170 insertions(+) >> create mode 100644 >> tools/testing/selftests/filesystems/fuse/fuse_symlink_cache_test.c >> >> diff --git a/tools/testing/selftests/filesystems/fuse/.gitignore >> b/tools/testing/selftests/filesystems/fuse/.gitignore >> index f7f3dd345a50..ebfe7133d811 100644 >> --- a/tools/testing/selftests/filesystems/fuse/.gitignore >> +++ b/tools/testing/selftests/filesystems/fuse/.gitignore >> @@ -3,3 +3,4 @@ fuse_mnt >> fusectl_test >> write_extend_eof_test >> fuse_acl_cache_test >> +fuse_symlink_cache_test >> diff --git a/tools/testing/selftests/filesystems/fuse/Makefile >> b/tools/testing/selftests/filesystems/fuse/Makefile >> index 7744f796eb06..3a5a557dde7a 100644 >> --- a/tools/testing/selftests/filesystems/fuse/Makefile >> +++ b/tools/testing/selftests/filesystems/fuse/Makefile >> @@ -5,6 +5,7 @@ CFLAGS += -Wall -O2 -g $(KHDR_INCLUDES) >> TEST_GEN_PROGS := fusectl_test >> TEST_GEN_PROGS += write_extend_eof_test >> TEST_GEN_PROGS += fuse_acl_cache_test >> +TEST_GEN_PROGS += fuse_symlink_cache_test >> TEST_GEN_FILES := fuse_mnt >> >> include ../../lib.mk >> @@ -28,5 +29,6 @@ $(OUTPUT)/fuse_mnt: CFLAGS += $(VAR_CFLAGS) >> $(OUTPUT)/fuse_mnt: LDLIBS += $(VAR_LDLIBS) >> >> $(OUTPUT)/fuse_acl_cache_test: fuse_common.c fuse_acl_cache_test.c >> +$(OUTPUT)/fuse_symlink_cache_test: fuse_common.c fuse_symlink_cache_test.c >> >> EXTRA_CLEAN := fuse_common.o >> diff --git >> a/tools/testing/selftests/filesystems/fuse/fuse_symlink_cache_test.c >> b/tools/testing/selftests/filesystems/fuse/fuse_symlink_cache_test.c >> new file mode 100644 >> index 000000000000..ca3c5cdaf578 >> --- /dev/null >> +++ b/tools/testing/selftests/filesystems/fuse/fuse_symlink_cache_test.c >> @@ -0,0 +1,167 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Simple filesystem to test FUSE symlink cache >> + * >> + * This is a simple FUSE filesystem that contains two objects: a file named >> + * 'file' and a symlink to that file named 'link'. If symlink caching is >> + * disabled (i.e. FUSE_CAP_CACHE_SYMLINKS is reset during FUSE_INIT), >> whenever >> + * the ->readlink() is executed to resolve 'link' a counter will be >> incremented. >> + * >> + * If symlink caching is enabled (i.e. FUSE_CAP_CACHE_SYMLINKS is set during >> + * FUSE_INIT), resolving a symlink will only call into user-space the first >> + * time. >> + */ >> + >> +#define FUSE_USE_VERSION 31 >> + >> +#include <stdio.h> >> +#include <limits.h> >> +#include <fuse_lowlevel.h> >> + >> +#include "kselftest_harness.h" >> + >> +#include "fuse_common.h" >> + >> +#define FILENAME "file" >> +#define FILE_INO 42 >> + >> +#define LINKNAME "link" >> +#define LINK_INO 43 >> + >> +#define TIMEOUT 86400.0f >> + >> +struct test_state { >> + pthread_mutex_t lock; >> + bool cache; >> + int readlink_counter; >> +} test_state = { >> + .lock = PTHREAD_MUTEX_INITIALIZER, >> +}; >> + >> +static void fs_init(void *userdata, struct fuse_conn_info *conn) >> +{ >> + pthread_mutex_lock(&test_state.lock); >> + if (test_state.cache) >> + fuse_set_feature_flag(conn, FUSE_CAP_CACHE_SYMLINKS); >> + else >> + fuse_unset_feature_flag(conn, FUSE_CAP_CACHE_SYMLINKS); >> + pthread_mutex_unlock(&test_state.lock); >> +} >> + >> +static void fs_lookup(fuse_req_t req, fuse_ino_t parent, const char *name) >> +{ >> + struct fuse_entry_param e = {}; >> + >> + if (parent != FUSE_ROOT_ID || >> + (!strcmp(name, FILENAME) && !(strcmp(name, LINKNAME)))) > > You probably meant strcmp() != 0 ... > Did you miss this Sashiko comment?
Oops! I did fix one similar comment (probably in a different test) but missed this one. I'll fix it for the next iteration. (And I'll still need to have a look at sashiko again for any new comments for this revision). Cheers, -- Luís
