38 #define FUSE_USE_VERSION 34    42 #include <fuse_lowlevel.h>    56 #include <sys/xattr.h>    58 #include "passthrough_helpers.h"    64 #if defined(__GNUC__) && (__GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ >= 6) && !defined __cplusplus    65 _Static_assert(
sizeof(
fuse_ino_t) >= 
sizeof(uintptr_t),
    66                "fuse_ino_t too small to hold uintptr_t values!");
    68 struct _uintptr_to_must_hold_fuse_ino_t_dummy_struct \
    69         { 
unsigned _uintptr_to_must_hold_fuse_ino_t:
    70                         ((
sizeof(
fuse_ino_t) >= 
sizeof(uintptr_t)) ? 1 : -1); };
    74         struct lo_inode *next; 
    75         struct lo_inode *prev; 
    89         pthread_mutex_t mutex;
   101 static const struct fuse_opt lo_opts[] = {
   103           offsetof(
struct lo_data, writeback), 1 },
   105           offsetof(
struct lo_data, writeback), 0 },
   107           offsetof(
struct lo_data, source), 0 },
   109           offsetof(
struct lo_data, flock), 1 },
   111           offsetof(
struct lo_data, flock), 0 },
   113           offsetof(
struct lo_data, xattr), 1 },
   115           offsetof(
struct lo_data, xattr), 0 },
   117           offsetof(
struct lo_data, timeout), 0 },
   119           offsetof(
struct lo_data, timeout_set), 1 },
   121           offsetof(
struct lo_data, cache), CACHE_NEVER },
   123           offsetof(
struct lo_data, cache), CACHE_NORMAL },
   125           offsetof(
struct lo_data, cache), CACHE_ALWAYS },
   130 static struct lo_data *lo_data(
fuse_req_t req)
   138                 return &lo_data(req)->root;
   140                 return (
struct lo_inode *) (uintptr_t) ino;
   145         return lo_inode(req, ino)->fd;
   150         return lo_data(req)->debug != 0;
   153 static void lo_init(
void *userdata,
   156         struct lo_data *lo = (
struct lo_data*) userdata;
   164                         fuse_log(FUSE_LOG_DEBUG, 
"lo_init: activating writeback\n");
   169                         fuse_log(FUSE_LOG_DEBUG, 
"lo_init: activating flock locks\n");
   179         struct lo_data *lo = lo_data(req);
   183         res = fstatat(lo_fd(req, ino), 
"", &buf, AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW);
   195         struct lo_inode *inode = lo_inode(req, ino);
   199         if (valid & FUSE_SET_ATTR_MODE) {
   201                         res = fchmod(fi->
fh, attr->st_mode);
   203                         sprintf(procname, 
"/proc/self/fd/%i", ifd);
   204                         res = chmod(procname, attr->st_mode);
   209         if (valid & (FUSE_SET_ATTR_UID | FUSE_SET_ATTR_GID)) {
   210                 uid_t uid = (valid & FUSE_SET_ATTR_UID) ?
   211                         attr->st_uid : (uid_t) -1;
   212                 gid_t gid = (valid & FUSE_SET_ATTR_GID) ?
   213                         attr->st_gid : (gid_t) -1;
   215                 res = fchownat(ifd, 
"", uid, gid,
   216                                AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW);
   220         if (valid & FUSE_SET_ATTR_SIZE) {
   222                         res = ftruncate(fi->
fh, attr->st_size);
   224                         sprintf(procname, 
"/proc/self/fd/%i", ifd);
   225                         res = truncate(procname, attr->st_size);
   230         if (valid & (FUSE_SET_ATTR_ATIME | FUSE_SET_ATTR_MTIME)) {
   231                 struct timespec tv[2];
   235                 tv[0].tv_nsec = UTIME_OMIT;
   236                 tv[1].tv_nsec = UTIME_OMIT;
   238                 if (valid & FUSE_SET_ATTR_ATIME_NOW)
   239                         tv[0].tv_nsec = UTIME_NOW;
   240                 else if (valid & FUSE_SET_ATTR_ATIME)
   241                         tv[0] = attr->st_atim;
   243                 if (valid & FUSE_SET_ATTR_MTIME_NOW)
   244                         tv[1].tv_nsec = UTIME_NOW;
   245                 else if (valid & FUSE_SET_ATTR_MTIME)
   246                         tv[1] = attr->st_mtim;
   249                         res = futimens(fi->
fh, tv);
   251                         sprintf(procname, 
"/proc/self/fd/%i", ifd);
   252                         res = utimensat(AT_FDCWD, procname, tv, 0);
   258         return lo_getattr(req, ino, fi);
   265 static struct lo_inode *lo_find(
struct lo_data *lo, 
struct stat *st)
   268         struct lo_inode *ret = NULL;
   270         pthread_mutex_lock(&lo->mutex);
   271         for (p = lo->root.next; p != &lo->root; p = p->next) {
   272                 if (p->ino == st->st_ino && p->dev == st->st_dev) {
   273                         assert(p->refcount > 0);
   279         pthread_mutex_unlock(&lo->mutex);
   289         struct lo_data *lo = lo_data(req);
   290         struct lo_inode *inode;
   292         memset(e, 0, 
sizeof(*e));
   296         newfd = openat(lo_fd(req, parent), name, O_PATH | O_NOFOLLOW);
   300         res = fstatat(newfd, 
"", &e->
attr, AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW);
   304         inode = lo_find(lo_data(req), &e->
attr);
   309                 struct lo_inode *prev, *next;
   312                 inode = calloc(1, 
sizeof(
struct lo_inode));
   318                 inode->ino = e->
attr.st_ino;
   319                 inode->dev = e->
attr.st_dev;
   321                 pthread_mutex_lock(&lo->mutex);
   328                 pthread_mutex_unlock(&lo->mutex);
   330         e->
ino = (uintptr_t) inode;
   333                 fuse_log(FUSE_LOG_DEBUG, 
"  %lli/%s -> %lli\n",
   334                         (
unsigned long long) parent, name, (
unsigned long long) e->
ino);
   351                 fuse_log(FUSE_LOG_DEBUG, 
"lo_lookup(parent=%" PRIu64 
", name=%s)\n",
   354         err = lo_do_lookup(req, parent, name, &e);
   362                              const char *name, mode_t mode, dev_t rdev,
   367         struct lo_inode *dir = lo_inode(req, parent);
   370         res = mknod_wrapper(dir->fd, name, link, mode, rdev);
   376         saverr = lo_do_lookup(req, parent, name, &e);
   381                 fuse_log(FUSE_LOG_DEBUG, 
"  %lli/%s -> %lli\n",
   382                         (
unsigned long long) parent, name, (
unsigned long long) e.
ino);
   392                      const char *name, mode_t mode, dev_t rdev)
   394         lo_mknod_symlink(req, parent, name, mode, rdev, NULL);
   400         lo_mknod_symlink(req, parent, name, S_IFDIR | mode, 0, NULL);
   403 static void lo_symlink(
fuse_req_t req, 
const char *link,
   406         lo_mknod_symlink(req, parent, name, S_IFLNK, 0, link);
   413         struct lo_data *lo = lo_data(req);
   414         struct lo_inode *inode = lo_inode(req, ino);
   423         sprintf(procname, 
"/proc/self/fd/%i", inode->fd);
   424         res = linkat(AT_FDCWD, procname, lo_fd(req, parent), name,
   429         res = fstatat(inode->fd, 
"", &e.
attr, AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW);
   433         pthread_mutex_lock(&lo->mutex);
   435         pthread_mutex_unlock(&lo->mutex);
   436         e.
ino = (uintptr_t) inode;
   439                 fuse_log(FUSE_LOG_DEBUG, 
"  %lli/%s -> %lli\n",
   440                         (
unsigned long long) parent, name,
   441                         (
unsigned long long) e.
ino);
   455         res = unlinkat(lo_fd(req, parent), name, AT_REMOVEDIR);
   471         res = renameat(lo_fd(req, parent), name,
   472                         lo_fd(req, newparent), newname);
   481         res = unlinkat(lo_fd(req, parent), name, 0);
   486 static void unref_inode(
struct lo_data *lo, 
struct lo_inode *inode, uint64_t n)
   491         pthread_mutex_lock(&lo->mutex);
   492         assert(inode->refcount >= n);
   493         inode->refcount -= n;
   494         if (!inode->refcount) {
   495                 struct lo_inode *prev, *next;
   502                 pthread_mutex_unlock(&lo->mutex);
   507                 pthread_mutex_unlock(&lo->mutex);
   513         struct lo_data *lo = lo_data(req);
   514         struct lo_inode *inode = lo_inode(req, ino);
   517                 fuse_log(FUSE_LOG_DEBUG, 
"  forget %lli %lli -%lli\n",
   518                         (
unsigned long long) ino,
   519                         (
unsigned long long) inode->refcount,
   520                         (
unsigned long long) nlookup);
   523         unref_inode(lo, inode, nlookup);
   528         lo_forget_one(req, ino, nlookup);
   532 static void lo_forget_multi(
fuse_req_t req, 
size_t count,
   533                                 struct fuse_forget_data *forgets)
   537         for (i = 0; i < count; i++)
   538                 lo_forget_one(req, forgets[i].ino, forgets[i].nlookup);
   544         char buf[PATH_MAX + 1];
   547         res = readlinkat(lo_fd(req, ino), 
"", buf, 
sizeof(buf));
   551         if (res == 
sizeof(buf))
   561         struct dirent *entry;
   567         return (
struct lo_dirp *) (uintptr_t) fi->
fh;
   573         struct lo_data *lo = lo_data(req);
   577         d = calloc(1, 
sizeof(
struct lo_dirp));
   581         fd = openat(lo_fd(req, ino), 
".", O_RDONLY);
   585         d->dp = fdopendir(fd);
   592         fi->
fh = (uintptr_t) d;
   593         if (lo->cache == CACHE_ALWAYS)
   609 static int is_dot_or_dotdot(
const char *name)
   611         return name[0] == 
'.' && (name[1] == 
'\0' ||
   612                                   (name[1] == 
'.' && name[2] == 
'\0'));
   618         struct lo_dirp *d = lo_dirp(fi);
   626         buf = calloc(1, size);
   633         if (offset != d->offset) {
   634                 seekdir(d->dp, offset);
   645                         d->entry = readdir(d->dp);
   655                 nextoff = d->entry->d_off;
   656                 name = d->entry->d_name;
   660                         if (is_dot_or_dotdot(name)) {
   662                                         .
attr.st_ino = d->entry->d_ino,
   663                                         .attr.st_mode = d->entry->d_type << 12,
   666                                 err = lo_do_lookup(req, ino, name, &e);
   676                                 .st_ino = d->entry->d_ino,
   677                                 .st_mode = d->entry->d_type << 12,
   684                                 lo_forget_one(req, entry_ino, 1);
   701     if (err && rem == size)
   711         lo_do_readdir(req, ino, size, offset, fi, 0);
   717         lo_do_readdir(req, ino, size, offset, fi, 1);
   722         struct lo_dirp *d = lo_dirp(fi);
   733         struct lo_data *lo = lo_data(req);
   738                 fuse_log(FUSE_LOG_DEBUG, 
"lo_create(parent=%" PRIu64 
", name=%s)\n",
   741         fd = openat(lo_fd(req, parent), name,
   742                     (fi->
flags | O_CREAT) & ~O_NOFOLLOW, mode);
   747         if (lo->cache == CACHE_NEVER)
   749         else if (lo->cache == CACHE_ALWAYS)
   752         err = lo_do_lookup(req, parent, name, &e);
   763         int fd = dirfd(lo_dirp(fi)->dp);
   776         struct lo_data *lo = lo_data(req);
   779                 fuse_log(FUSE_LOG_DEBUG, 
"lo_open(ino=%" PRIu64 
", flags=%d)\n",
   784         if (lo->writeback && (fi->
flags & O_ACCMODE) == O_WRONLY) {
   785                 fi->
flags &= ~O_ACCMODE;
   795         if (lo->writeback && (fi->
flags & O_APPEND))
   796                 fi->
flags &= ~O_APPEND;
   798         sprintf(buf, 
"/proc/self/fd/%i", lo_fd(req, ino));
   799         fd = open(buf, fi->
flags & ~O_NOFOLLOW);
   804         if (lo->cache == CACHE_NEVER)
   806         else if (lo->cache == CACHE_ALWAYS)
   823         res = close(dup(fi->
fh));
   833                 res = fdatasync(fi->
fh);
   845                 fuse_log(FUSE_LOG_DEBUG, 
"lo_read(ino=%" PRIu64 
", size=%zd, "   846                         "off=%lu)\n", ino, size, (
unsigned long) offset);
   868                 fuse_log(FUSE_LOG_DEBUG, 
"lo_write(ino=%" PRIu64 
", size=%zd, off=%lu)\n",
   869                         ino, out_buf.
buf[0].
size, (
unsigned long) off);
   881         struct statvfs stbuf;
   883         res = fstatvfs(lo_fd(req, ino), &stbuf);
   893         int err = EOPNOTSUPP;
   896 #ifdef HAVE_FALLOCATE   897         err = fallocate(fi->
fh, mode, offset, length);
   901 #elif defined(HAVE_POSIX_FALLOCATE)   907         err = posix_fallocate(fi->
fh, offset, length);
   919         res = flock(fi->
fh, op);
   929         struct lo_inode *inode = lo_inode(req, ino);
   934         if (!lo_data(req)->xattr)
   938                 fuse_log(FUSE_LOG_DEBUG, 
"lo_getxattr(ino=%" PRIu64 
", name=%s size=%zd)\n",
   942         sprintf(procname, 
"/proc/self/fd/%i", inode->fd);
   945                 value = malloc(size);
   949                 ret = getxattr(procname, name, value, size);
   958                 ret = getxattr(procname, name, NULL, 0);
   979         struct lo_inode *inode = lo_inode(req, ino);
   984         if (!lo_data(req)->xattr)
   988                 fuse_log(FUSE_LOG_DEBUG, 
"lo_listxattr(ino=%" PRIu64 
", size=%zd)\n",
   992         sprintf(procname, 
"/proc/self/fd/%i", inode->fd);
   995                 value = malloc(size);
   999                 ret = listxattr(procname, value, size);
  1008                 ret = listxattr(procname, NULL, 0);
  1026                         const char *value, 
size_t size, 
int flags)
  1029         struct lo_inode *inode = lo_inode(req, ino);
  1034         if (!lo_data(req)->xattr)
  1037         if (lo_debug(req)) {
  1038                 fuse_log(FUSE_LOG_DEBUG, 
"lo_setxattr(ino=%" PRIu64 
", name=%s value=%s size=%zd)\n",
  1039                         ino, name, value, size);
  1042         sprintf(procname, 
"/proc/self/fd/%i", inode->fd);
  1044         ret = setxattr(procname, name, value, size, flags);
  1045         saverr = ret == -1 ? errno : 0;
  1054         struct lo_inode *inode = lo_inode(req, ino);
  1059         if (!lo_data(req)->xattr)
  1062         if (lo_debug(req)) {
  1063                 fuse_log(FUSE_LOG_DEBUG, 
"lo_removexattr(ino=%" PRIu64 
", name=%s)\n",
  1067         sprintf(procname, 
"/proc/self/fd/%i", inode->fd);
  1069         ret = removexattr(procname, name);
  1070         saverr = ret == -1 ? errno : 0;
  1076 #ifdef HAVE_COPY_FILE_RANGE  1086                 fuse_log(FUSE_LOG_DEBUG, 
"lo_copy_file_range(ino=%" PRIu64 
"/fd=%lu, "  1087                                 "off=%lu, ino=%" PRIu64 
"/fd=%lu, "  1088                                 "off=%lu, size=%zd, flags=0x%x)\n",
  1089                         ino_in, fi_in->
fh, off_in, ino_out, fi_out->
fh, off_out,
  1092         res = copy_file_range(fi_in->
fh, &off_in, fi_out->
fh, &off_out, len,
  1107         res = lseek(fi->
fh, off, whence);
  1116         .lookup         = lo_lookup,
  1119         .symlink        = lo_symlink,
  1121         .unlink         = lo_unlink,
  1123         .rename         = lo_rename,
  1124         .forget         = lo_forget,
  1125         .forget_multi   = lo_forget_multi,
  1126         .getattr        = lo_getattr,
  1127         .setattr        = lo_setattr,
  1128         .readlink       = lo_readlink,
  1129         .opendir        = lo_opendir,
  1130         .readdir        = lo_readdir,
  1131         .readdirplus    = lo_readdirplus,
  1132         .releasedir     = lo_releasedir,
  1133         .fsyncdir       = lo_fsyncdir,
  1134         .create         = lo_create,
  1136         .release        = lo_release,
  1140         .write_buf      = lo_write_buf,
  1141         .statfs         = lo_statfs,
  1142         .fallocate      = lo_fallocate,
  1144         .getxattr       = lo_getxattr,
  1145         .listxattr      = lo_listxattr,
  1146         .setxattr       = lo_setxattr,
  1147         .removexattr    = lo_removexattr,
  1148 #ifdef HAVE_COPY_FILE_RANGE  1149         .copy_file_range = lo_copy_file_range,
  1154 int main(
int argc, 
char *argv[])
  1157         struct fuse_session *se;
  1158         struct fuse_cmdline_opts opts;
  1160         struct lo_data lo = { .debug = 0,
  1167         pthread_mutex_init(&lo.mutex, NULL);
  1168         lo.root.next = lo.root.prev = &lo.root;
  1170         lo.cache = CACHE_NORMAL;
  1174         if (opts.show_help) {
  1175                 printf(
"usage: %s [options] <mountpoint>\n\n", argv[0]);
  1180         } 
else if (opts.show_version) {
  1187         if(opts.mountpoint == NULL) {
  1188                 printf(
"usage: %s [options] <mountpoint>\n", argv[0]);
  1189                 printf(
"       %s --help\n", argv[0]);
  1197         lo.debug = opts.debug;
  1198         lo.root.refcount = 2;
  1203                 res = lstat(lo.source, &stat);
  1205                         fuse_log(FUSE_LOG_ERR, 
"failed to stat source (\"%s\"): %m\n",
  1209                 if (!S_ISDIR(stat.st_mode)) {
  1210                         fuse_log(FUSE_LOG_ERR, 
"source is not a directory\n");
  1217         if (!lo.timeout_set) {
  1228                         lo.timeout = 86400.0;
  1231         } 
else if (lo.timeout < 0) {
  1232                 fuse_log(FUSE_LOG_ERR, 
"timeout is negative (%lf)\n",
  1237         lo.root.fd = open(lo.source, O_PATH);
  1238         if (lo.root.fd == -1) {
  1239                 fuse_log(FUSE_LOG_ERR, 
"open(\"%s\", O_PATH): %m\n",
  1257         if (opts.singlethread)
  1260                 config.clone_fd = opts.clone_fd;
  1261                 config.max_idle_threads = opts.max_idle_threads;
  1271         free(opts.mountpoint);
  1274         if (lo.root.fd >= 0)
 
struct fuse_session * fuse_session_new(struct fuse_args *args, const struct fuse_lowlevel_ops *op, size_t op_size, void *userdata)
void fuse_lowlevel_help(void)
int fuse_reply_open(fuse_req_t req, const struct fuse_file_info *fi)
int fuse_reply_buf(fuse_req_t req, const char *buf, size_t size)
int fuse_reply_entry(fuse_req_t req, const struct fuse_entry_param *e)
void fuse_lowlevel_version(void)
size_t fuse_buf_size(const struct fuse_bufvec *bufv)
size_t fuse_add_direntry(fuse_req_t req, char *buf, size_t bufsize, const char *name, const struct stat *stbuf, off_t off)
void fuse_session_destroy(struct fuse_session *se)
int fuse_session_loop(struct fuse_session *se)
int fuse_reply_data(fuse_req_t req, struct fuse_bufvec *bufv, enum fuse_buf_copy_flags flags)
int fuse_daemonize(int foreground)
struct fuse_req * fuse_req_t
int fuse_reply_lseek(fuse_req_t req, off_t off)
int fuse_set_signal_handlers(struct fuse_session *se)
void * fuse_req_userdata(fuse_req_t req)
int fuse_session_mount(struct fuse_session *se, const char *mountpoint)
int fuse_reply_xattr(fuse_req_t req, size_t count)
void fuse_cmdline_help(void)
void fuse_opt_free_args(struct fuse_args *args)
int fuse_reply_create(fuse_req_t req, const struct fuse_entry_param *e, const struct fuse_file_info *fi)
#define FUSE_CAP_WRITEBACK_CACHE
enum fuse_buf_flags flags
ssize_t fuse_buf_copy(struct fuse_bufvec *dst, struct fuse_bufvec *src, enum fuse_buf_copy_flags flags)
#define FUSE_CAP_FLOCK_LOCKS
int fuse_reply_readlink(fuse_req_t req, const char *link)
int fuse_reply_err(fuse_req_t req, int err)
int fuse_reply_attr(fuse_req_t req, const struct stat *attr, double attr_timeout)
int fuse_parse_cmdline(struct fuse_args *args, struct fuse_cmdline_opts *opts)
size_t fuse_add_direntry_plus(fuse_req_t req, char *buf, size_t bufsize, const char *name, const struct fuse_entry_param *e, off_t off)
void fuse_reply_none(fuse_req_t req)
void fuse_log(enum fuse_log_level level, const char *fmt,...)
unsigned int cache_readdir
int fuse_opt_parse(struct fuse_args *args, void *data, const struct fuse_opt opts[], fuse_opt_proc_t proc)
const char * fuse_pkgversion(void)
int fuse_reply_statfs(fuse_req_t req, const struct statvfs *stbuf)
void fuse_session_unmount(struct fuse_session *se)
int fuse_reply_write(fuse_req_t req, size_t count)
#define FUSE_ARGS_INIT(argc, argv)
void fuse_remove_signal_handlers(struct fuse_session *se)
void(* init)(void *userdata, struct fuse_conn_info *conn)
#define FUSE_CAP_EXPORT_SUPPORT
int fuse_session_loop_mt(struct fuse_session *se, struct fuse_loop_config *config)