1
2
3
4
5
6
7
8
9
10
11
12
13#include "qemu/osdep.h"
14#include "fuse_i.h"
15#include "fuse_lowlevel.h"
16#include "fuse_misc.h"
17#include "fuse_opt.h"
18
19#include <sys/param.h>
20#include <sys/resource.h>
21
22#define FUSE_HELPER_OPT(t, p) \
23 { \
24 t, offsetof(struct fuse_cmdline_opts, p), 1 \
25 }
26#define FUSE_HELPER_OPT_VALUE(t, p, v) \
27 { \
28 t, offsetof(struct fuse_cmdline_opts, p), v \
29 }
30
31static const struct fuse_opt fuse_helper_opts[] = {
32 FUSE_HELPER_OPT("-h", show_help),
33 FUSE_HELPER_OPT("--help", show_help),
34 FUSE_HELPER_OPT("-V", show_version),
35 FUSE_HELPER_OPT("--version", show_version),
36 FUSE_HELPER_OPT("--print-capabilities", print_capabilities),
37 FUSE_HELPER_OPT("-d", debug),
38 FUSE_HELPER_OPT("debug", debug),
39 FUSE_HELPER_OPT("-d", foreground),
40 FUSE_HELPER_OPT("debug", foreground),
41 FUSE_OPT_KEY("-d", FUSE_OPT_KEY_KEEP),
42 FUSE_OPT_KEY("debug", FUSE_OPT_KEY_KEEP),
43 FUSE_HELPER_OPT("-f", foreground),
44 FUSE_HELPER_OPT_VALUE("--daemonize", foreground, 0),
45 FUSE_HELPER_OPT("fsname=", nodefault_subtype),
46 FUSE_OPT_KEY("fsname=", FUSE_OPT_KEY_KEEP),
47 FUSE_HELPER_OPT("subtype=", nodefault_subtype),
48 FUSE_OPT_KEY("subtype=", FUSE_OPT_KEY_KEEP),
49 FUSE_HELPER_OPT("max_idle_threads=%u", max_idle_threads),
50 FUSE_HELPER_OPT("--rlimit-nofile=%lu", rlimit_nofile),
51 FUSE_HELPER_OPT("--syslog", syslog),
52 FUSE_HELPER_OPT_VALUE("log_level=debug", log_level, FUSE_LOG_DEBUG),
53 FUSE_HELPER_OPT_VALUE("log_level=info", log_level, FUSE_LOG_INFO),
54 FUSE_HELPER_OPT_VALUE("log_level=warn", log_level, FUSE_LOG_WARNING),
55 FUSE_HELPER_OPT_VALUE("log_level=err", log_level, FUSE_LOG_ERR),
56 FUSE_OPT_END
57};
58
59struct fuse_conn_info_opts {
60 int atomic_o_trunc;
61 int no_remote_posix_lock;
62 int no_remote_flock;
63 int splice_write;
64 int splice_move;
65 int splice_read;
66 int no_splice_write;
67 int no_splice_move;
68 int no_splice_read;
69 int auto_inval_data;
70 int no_auto_inval_data;
71 int no_readdirplus;
72 int no_readdirplus_auto;
73 int async_dio;
74 int no_async_dio;
75 int writeback_cache;
76 int no_writeback_cache;
77 int async_read;
78 int sync_read;
79 unsigned max_write;
80 unsigned max_readahead;
81 unsigned max_background;
82 unsigned congestion_threshold;
83 unsigned time_gran;
84 int set_max_write;
85 int set_max_readahead;
86 int set_max_background;
87 int set_congestion_threshold;
88 int set_time_gran;
89};
90
91#define CONN_OPTION(t, p, v) \
92 { \
93 t, offsetof(struct fuse_conn_info_opts, p), v \
94 }
95static const struct fuse_opt conn_info_opt_spec[] = {
96 CONN_OPTION("max_write=%u", max_write, 0),
97 CONN_OPTION("max_write=", set_max_write, 1),
98 CONN_OPTION("max_readahead=%u", max_readahead, 0),
99 CONN_OPTION("max_readahead=", set_max_readahead, 1),
100 CONN_OPTION("max_background=%u", max_background, 0),
101 CONN_OPTION("max_background=", set_max_background, 1),
102 CONN_OPTION("congestion_threshold=%u", congestion_threshold, 0),
103 CONN_OPTION("congestion_threshold=", set_congestion_threshold, 1),
104 CONN_OPTION("sync_read", sync_read, 1),
105 CONN_OPTION("async_read", async_read, 1),
106 CONN_OPTION("atomic_o_trunc", atomic_o_trunc, 1),
107 CONN_OPTION("no_remote_lock", no_remote_posix_lock, 1),
108 CONN_OPTION("no_remote_lock", no_remote_flock, 1),
109 CONN_OPTION("no_remote_flock", no_remote_flock, 1),
110 CONN_OPTION("no_remote_posix_lock", no_remote_posix_lock, 1),
111 CONN_OPTION("splice_write", splice_write, 1),
112 CONN_OPTION("no_splice_write", no_splice_write, 1),
113 CONN_OPTION("splice_move", splice_move, 1),
114 CONN_OPTION("no_splice_move", no_splice_move, 1),
115 CONN_OPTION("splice_read", splice_read, 1),
116 CONN_OPTION("no_splice_read", no_splice_read, 1),
117 CONN_OPTION("auto_inval_data", auto_inval_data, 1),
118 CONN_OPTION("no_auto_inval_data", no_auto_inval_data, 1),
119 CONN_OPTION("readdirplus=no", no_readdirplus, 1),
120 CONN_OPTION("readdirplus=yes", no_readdirplus, 0),
121 CONN_OPTION("readdirplus=yes", no_readdirplus_auto, 1),
122 CONN_OPTION("readdirplus=auto", no_readdirplus, 0),
123 CONN_OPTION("readdirplus=auto", no_readdirplus_auto, 0),
124 CONN_OPTION("async_dio", async_dio, 1),
125 CONN_OPTION("no_async_dio", no_async_dio, 1),
126 CONN_OPTION("writeback_cache", writeback_cache, 1),
127 CONN_OPTION("no_writeback_cache", no_writeback_cache, 1),
128 CONN_OPTION("time_gran=%u", time_gran, 0),
129 CONN_OPTION("time_gran=", set_time_gran, 1),
130 FUSE_OPT_END
131};
132
133
134void fuse_cmdline_help(void)
135{
136 printf(" -h --help print help\n"
137 " -V --version print version\n"
138 " --print-capabilities print vhost-user.json\n"
139 " -d -o debug enable debug output (implies -f)\n"
140 " --syslog log to syslog (default stderr)\n"
141 " -f foreground operation\n"
142 " --daemonize run in background\n"
143 " -o cache=<mode> cache mode. could be one of \"auto, "
144 "always, none\"\n"
145 " default: auto\n"
146 " -o flock|no_flock enable/disable flock\n"
147 " default: no_flock\n"
148 " -o log_level=<level> log level, default to \"info\"\n"
149 " level could be one of \"debug, "
150 "info, warn, err\"\n"
151 " -o max_idle_threads the maximum number of idle worker "
152 "threads\n"
153 " allowed (default: 10)\n"
154 " -o posix_lock|no_posix_lock\n"
155 " enable/disable remote posix lock\n"
156 " default: no_posix_lock\n"
157 " -o readdirplus|no_readdirplus\n"
158 " enable/disable readirplus\n"
159 " default: readdirplus except with "
160 "cache=none\n"
161 " -o sandbox=namespace|chroot\n"
162 " sandboxing mode:\n"
163 " - namespace: mount, pid, and net\n"
164 " namespaces with pivot_root(2)\n"
165 " into shared directory\n"
166 " - chroot: chroot(2) into shared\n"
167 " directory (use in containers)\n"
168 " default: namespace\n"
169 " -o timeout=<number> I/O timeout (seconds)\n"
170 " default: depends on cache= option.\n"
171 " -o writeback|no_writeback enable/disable writeback cache\n"
172 " default: no_writeback\n"
173 " -o xattr|no_xattr enable/disable xattr\n"
174 " default: no_xattr\n"
175 " -o modcaps=CAPLIST Modify the list of capabilities\n"
176 " e.g. -o modcaps=+sys_admin:-chown\n"
177 " --rlimit-nofile=<num> set maximum number of file descriptors\n"
178 " (0 leaves rlimit unchanged)\n"
179 " default: min(1000000, fs.file-max - 16384)\n"
180 " if the current rlimit is lower\n"
181 " -o allow_direct_io|no_allow_direct_io\n"
182 " retain/discard O_DIRECT flags passed down\n"
183 " to virtiofsd from guest applications.\n"
184 " default: no_allow_direct_io\n"
185 " -o announce_submounts Announce sub-mount points to the guest\n"
186 );
187}
188
189static int fuse_helper_opt_proc(void *data, const char *arg, int key,
190 struct fuse_args *outargs)
191{
192 (void)data;
193 (void)outargs;
194
195 switch (key) {
196 case FUSE_OPT_KEY_NONOPT:
197 fuse_log(FUSE_LOG_ERR, "fuse: invalid argument `%s'\n", arg);
198 return -1;
199
200 default:
201
202 return 1;
203 }
204}
205
206static unsigned long get_default_rlimit_nofile(void)
207{
208 g_autofree gchar *file_max_str = NULL;
209 const rlim_t reserved_fds = 16384;
210 rlim_t max_fds = 1000000;
211 rlim_t file_max;
212 struct rlimit rlim;
213
214
215
216
217
218
219 if (!g_file_get_contents("/proc/sys/fs/file-max", &file_max_str,
220 NULL, NULL)) {
221 fuse_log(FUSE_LOG_ERR, "can't read /proc/sys/fs/file-max\n");
222 exit(1);
223 }
224 file_max = g_ascii_strtoull(file_max_str, NULL, 10);
225 if (file_max < 2 * reserved_fds) {
226 fuse_log(FUSE_LOG_ERR,
227 "The fs.file-max sysctl is too low (%lu) to allow a "
228 "reasonable number of open files.\n",
229 (unsigned long)file_max);
230 exit(1);
231 }
232 max_fds = MIN(file_max - reserved_fds, max_fds);
233
234 if (getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
235 fuse_log(FUSE_LOG_ERR, "getrlimit(RLIMIT_NOFILE): %m\n");
236 exit(1);
237 }
238
239 if (rlim.rlim_cur >= max_fds) {
240 return 0;
241 }
242 return max_fds;
243}
244
245int fuse_parse_cmdline(struct fuse_args *args, struct fuse_cmdline_opts *opts)
246{
247 memset(opts, 0, sizeof(struct fuse_cmdline_opts));
248
249 opts->max_idle_threads = 10;
250 opts->rlimit_nofile = get_default_rlimit_nofile();
251 opts->foreground = 1;
252
253 if (fuse_opt_parse(args, opts, fuse_helper_opts, fuse_helper_opt_proc) ==
254 -1) {
255 return -1;
256 }
257
258 return 0;
259}
260
261
262int fuse_daemonize(int foreground)
263{
264 int ret = 0, rett;
265 if (!foreground) {
266 int nullfd;
267 int waiter[2];
268 char completed;
269
270 if (pipe(waiter)) {
271 fuse_log(FUSE_LOG_ERR, "fuse_daemonize: pipe: %s\n",
272 strerror(errno));
273 return -1;
274 }
275
276
277
278
279
280 switch (fork()) {
281 case -1:
282 fuse_log(FUSE_LOG_ERR, "fuse_daemonize: fork: %s\n",
283 strerror(errno));
284 return -1;
285 case 0:
286 break;
287 default:
288 _exit(read(waiter[0], &completed,
289 sizeof(completed) != sizeof(completed)));
290 }
291
292 if (setsid() == -1) {
293 fuse_log(FUSE_LOG_ERR, "fuse_daemonize: setsid: %s\n",
294 strerror(errno));
295 return -1;
296 }
297
298 ret = chdir("/");
299
300 nullfd = open("/dev/null", O_RDWR, 0);
301 if (nullfd != -1) {
302 rett = dup2(nullfd, 0);
303 if (!ret) {
304 ret = rett;
305 }
306 rett = dup2(nullfd, 1);
307 if (!ret) {
308 ret = rett;
309 }
310 rett = dup2(nullfd, 2);
311 if (!ret) {
312 ret = rett;
313 }
314 if (nullfd > 2) {
315 close(nullfd);
316 }
317 }
318
319
320 completed = 1;
321 rett = write(waiter[1], &completed, sizeof(completed));
322 if (!ret) {
323 ret = rett;
324 }
325 close(waiter[0]);
326 close(waiter[1]);
327 } else {
328 ret = chdir("/");
329 }
330 return ret;
331}
332
333void fuse_apply_conn_info_opts(struct fuse_conn_info_opts *opts,
334 struct fuse_conn_info *conn)
335{
336 if (opts->set_max_write) {
337 conn->max_write = opts->max_write;
338 }
339 if (opts->set_max_background) {
340 conn->max_background = opts->max_background;
341 }
342 if (opts->set_congestion_threshold) {
343 conn->congestion_threshold = opts->congestion_threshold;
344 }
345 if (opts->set_time_gran) {
346 conn->time_gran = opts->time_gran;
347 }
348 if (opts->set_max_readahead) {
349 conn->max_readahead = opts->max_readahead;
350 }
351
352#define LL_ENABLE(cond, cap) \
353 if (cond) \
354 conn->want |= (cap)
355#define LL_DISABLE(cond, cap) \
356 if (cond) \
357 conn->want &= ~(cap)
358
359 LL_ENABLE(opts->splice_read, FUSE_CAP_SPLICE_READ);
360 LL_DISABLE(opts->no_splice_read, FUSE_CAP_SPLICE_READ);
361
362 LL_ENABLE(opts->splice_write, FUSE_CAP_SPLICE_WRITE);
363 LL_DISABLE(opts->no_splice_write, FUSE_CAP_SPLICE_WRITE);
364
365 LL_ENABLE(opts->splice_move, FUSE_CAP_SPLICE_MOVE);
366 LL_DISABLE(opts->no_splice_move, FUSE_CAP_SPLICE_MOVE);
367
368 LL_ENABLE(opts->auto_inval_data, FUSE_CAP_AUTO_INVAL_DATA);
369 LL_DISABLE(opts->no_auto_inval_data, FUSE_CAP_AUTO_INVAL_DATA);
370
371 LL_DISABLE(opts->no_readdirplus, FUSE_CAP_READDIRPLUS);
372 LL_DISABLE(opts->no_readdirplus_auto, FUSE_CAP_READDIRPLUS_AUTO);
373
374 LL_ENABLE(opts->async_dio, FUSE_CAP_ASYNC_DIO);
375 LL_DISABLE(opts->no_async_dio, FUSE_CAP_ASYNC_DIO);
376
377 LL_ENABLE(opts->writeback_cache, FUSE_CAP_WRITEBACK_CACHE);
378 LL_DISABLE(opts->no_writeback_cache, FUSE_CAP_WRITEBACK_CACHE);
379
380 LL_ENABLE(opts->async_read, FUSE_CAP_ASYNC_READ);
381 LL_DISABLE(opts->sync_read, FUSE_CAP_ASYNC_READ);
382
383 LL_DISABLE(opts->no_remote_posix_lock, FUSE_CAP_POSIX_LOCKS);
384 LL_DISABLE(opts->no_remote_flock, FUSE_CAP_FLOCK_LOCKS);
385}
386
387struct fuse_conn_info_opts *fuse_parse_conn_info_opts(struct fuse_args *args)
388{
389 struct fuse_conn_info_opts *opts;
390
391 opts = calloc(1, sizeof(struct fuse_conn_info_opts));
392 if (opts == NULL) {
393 fuse_log(FUSE_LOG_ERR, "calloc failed\n");
394 return NULL;
395 }
396 if (fuse_opt_parse(args, opts, conn_info_opt_spec, NULL) == -1) {
397 free(opts);
398 return NULL;
399 }
400 return opts;
401}
402
