forked from mirror/qemu
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
410 lines
15 KiB
C
410 lines
15 KiB
C
/*
|
|
* FUSE: Filesystem in Userspace
|
|
* Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
|
|
*
|
|
* Helper functions to create (simple) standalone programs. With the
|
|
* aid of these functions it should be possible to create full FUSE
|
|
* file system by implementing nothing but the request handlers.
|
|
|
|
* This program can be distributed under the terms of the GNU LGPLv2.
|
|
* See the file COPYING.LIB.
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "fuse_i.h"
|
|
#include "fuse_lowlevel.h"
|
|
#include "fuse_misc.h"
|
|
#include "fuse_opt.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/resource.h>
|
|
|
|
#define FUSE_HELPER_OPT(t, p) \
|
|
{ \
|
|
t, offsetof(struct fuse_cmdline_opts, p), 1 \
|
|
}
|
|
#define FUSE_HELPER_OPT_VALUE(t, p, v) \
|
|
{ \
|
|
t, offsetof(struct fuse_cmdline_opts, p), v \
|
|
}
|
|
|
|
static const struct fuse_opt fuse_helper_opts[] = {
|
|
FUSE_HELPER_OPT("-h", show_help),
|
|
FUSE_HELPER_OPT("--help", show_help),
|
|
FUSE_HELPER_OPT("-V", show_version),
|
|
FUSE_HELPER_OPT("--version", show_version),
|
|
FUSE_HELPER_OPT("--print-capabilities", print_capabilities),
|
|
FUSE_HELPER_OPT("-d", debug),
|
|
FUSE_HELPER_OPT("debug", debug),
|
|
FUSE_HELPER_OPT("-d", foreground),
|
|
FUSE_HELPER_OPT("debug", foreground),
|
|
FUSE_OPT_KEY("-d", FUSE_OPT_KEY_KEEP),
|
|
FUSE_OPT_KEY("debug", FUSE_OPT_KEY_KEEP),
|
|
FUSE_HELPER_OPT("-f", foreground),
|
|
FUSE_HELPER_OPT_VALUE("--daemonize", foreground, 0),
|
|
FUSE_HELPER_OPT("fsname=", nodefault_subtype),
|
|
FUSE_OPT_KEY("fsname=", FUSE_OPT_KEY_KEEP),
|
|
FUSE_HELPER_OPT("subtype=", nodefault_subtype),
|
|
FUSE_OPT_KEY("subtype=", FUSE_OPT_KEY_KEEP),
|
|
FUSE_HELPER_OPT("max_idle_threads=%u", max_idle_threads),
|
|
FUSE_HELPER_OPT("--rlimit-nofile=%lu", rlimit_nofile),
|
|
FUSE_HELPER_OPT("--syslog", syslog),
|
|
FUSE_HELPER_OPT_VALUE("log_level=debug", log_level, FUSE_LOG_DEBUG),
|
|
FUSE_HELPER_OPT_VALUE("log_level=info", log_level, FUSE_LOG_INFO),
|
|
FUSE_HELPER_OPT_VALUE("log_level=warn", log_level, FUSE_LOG_WARNING),
|
|
FUSE_HELPER_OPT_VALUE("log_level=err", log_level, FUSE_LOG_ERR),
|
|
FUSE_OPT_END
|
|
};
|
|
|
|
struct fuse_conn_info_opts {
|
|
int atomic_o_trunc;
|
|
int no_remote_posix_lock;
|
|
int no_remote_flock;
|
|
int splice_write;
|
|
int splice_move;
|
|
int splice_read;
|
|
int no_splice_write;
|
|
int no_splice_move;
|
|
int no_splice_read;
|
|
int auto_inval_data;
|
|
int no_auto_inval_data;
|
|
int no_readdirplus;
|
|
int no_readdirplus_auto;
|
|
int async_dio;
|
|
int no_async_dio;
|
|
int writeback_cache;
|
|
int no_writeback_cache;
|
|
int async_read;
|
|
int sync_read;
|
|
unsigned max_write;
|
|
unsigned max_readahead;
|
|
unsigned max_background;
|
|
unsigned congestion_threshold;
|
|
unsigned time_gran;
|
|
int set_max_write;
|
|
int set_max_readahead;
|
|
int set_max_background;
|
|
int set_congestion_threshold;
|
|
int set_time_gran;
|
|
};
|
|
|
|
#define CONN_OPTION(t, p, v) \
|
|
{ \
|
|
t, offsetof(struct fuse_conn_info_opts, p), v \
|
|
}
|
|
static const struct fuse_opt conn_info_opt_spec[] = {
|
|
CONN_OPTION("max_write=%u", max_write, 0),
|
|
CONN_OPTION("max_write=", set_max_write, 1),
|
|
CONN_OPTION("max_readahead=%u", max_readahead, 0),
|
|
CONN_OPTION("max_readahead=", set_max_readahead, 1),
|
|
CONN_OPTION("max_background=%u", max_background, 0),
|
|
CONN_OPTION("max_background=", set_max_background, 1),
|
|
CONN_OPTION("congestion_threshold=%u", congestion_threshold, 0),
|
|
CONN_OPTION("congestion_threshold=", set_congestion_threshold, 1),
|
|
CONN_OPTION("sync_read", sync_read, 1),
|
|
CONN_OPTION("async_read", async_read, 1),
|
|
CONN_OPTION("atomic_o_trunc", atomic_o_trunc, 1),
|
|
CONN_OPTION("no_remote_lock", no_remote_posix_lock, 1),
|
|
CONN_OPTION("no_remote_lock", no_remote_flock, 1),
|
|
CONN_OPTION("no_remote_flock", no_remote_flock, 1),
|
|
CONN_OPTION("no_remote_posix_lock", no_remote_posix_lock, 1),
|
|
CONN_OPTION("splice_write", splice_write, 1),
|
|
CONN_OPTION("no_splice_write", no_splice_write, 1),
|
|
CONN_OPTION("splice_move", splice_move, 1),
|
|
CONN_OPTION("no_splice_move", no_splice_move, 1),
|
|
CONN_OPTION("splice_read", splice_read, 1),
|
|
CONN_OPTION("no_splice_read", no_splice_read, 1),
|
|
CONN_OPTION("auto_inval_data", auto_inval_data, 1),
|
|
CONN_OPTION("no_auto_inval_data", no_auto_inval_data, 1),
|
|
CONN_OPTION("readdirplus=no", no_readdirplus, 1),
|
|
CONN_OPTION("readdirplus=yes", no_readdirplus, 0),
|
|
CONN_OPTION("readdirplus=yes", no_readdirplus_auto, 1),
|
|
CONN_OPTION("readdirplus=auto", no_readdirplus, 0),
|
|
CONN_OPTION("readdirplus=auto", no_readdirplus_auto, 0),
|
|
CONN_OPTION("async_dio", async_dio, 1),
|
|
CONN_OPTION("no_async_dio", no_async_dio, 1),
|
|
CONN_OPTION("writeback_cache", writeback_cache, 1),
|
|
CONN_OPTION("no_writeback_cache", no_writeback_cache, 1),
|
|
CONN_OPTION("time_gran=%u", time_gran, 0),
|
|
CONN_OPTION("time_gran=", set_time_gran, 1),
|
|
FUSE_OPT_END
|
|
};
|
|
|
|
|
|
void fuse_cmdline_help(void)
|
|
{
|
|
printf(" -h --help print help\n"
|
|
" -V --version print version\n"
|
|
" --print-capabilities print vhost-user.json\n"
|
|
" -d -o debug enable debug output (implies -f)\n"
|
|
" --syslog log to syslog (default stderr)\n"
|
|
" -f foreground operation\n"
|
|
" --daemonize run in background\n"
|
|
" -o cache=<mode> cache mode. could be one of \"auto, "
|
|
"always, none\"\n"
|
|
" default: auto\n"
|
|
" -o flock|no_flock enable/disable flock\n"
|
|
" default: no_flock\n"
|
|
" -o log_level=<level> log level, default to \"info\"\n"
|
|
" level could be one of \"debug, "
|
|
"info, warn, err\"\n"
|
|
" -o max_idle_threads the maximum number of idle worker "
|
|
"threads\n"
|
|
" allowed (default: 10)\n"
|
|
" -o posix_lock|no_posix_lock\n"
|
|
" enable/disable remote posix lock\n"
|
|
" default: no_posix_lock\n"
|
|
" -o readdirplus|no_readdirplus\n"
|
|
" enable/disable readirplus\n"
|
|
" default: readdirplus except with "
|
|
"cache=none\n"
|
|
" -o sandbox=namespace|chroot\n"
|
|
" sandboxing mode:\n"
|
|
" - namespace: mount, pid, and net\n"
|
|
" namespaces with pivot_root(2)\n"
|
|
" into shared directory\n"
|
|
" - chroot: chroot(2) into shared\n"
|
|
" directory (use in containers)\n"
|
|
" default: namespace\n"
|
|
" -o timeout=<number> I/O timeout (seconds)\n"
|
|
" default: depends on cache= option.\n"
|
|
" -o writeback|no_writeback enable/disable writeback cache\n"
|
|
" default: no_writeback\n"
|
|
" -o xattr|no_xattr enable/disable xattr\n"
|
|
" default: no_xattr\n"
|
|
" -o xattrmap=<mapping> Enable xattr mapping (enables xattr)\n"
|
|
" <mapping> is a string consists of a series of rules\n"
|
|
" e.g. -o xattrmap=:map::user.virtiofs.:\n"
|
|
" -o modcaps=CAPLIST Modify the list of capabilities\n"
|
|
" e.g. -o modcaps=+sys_admin:-chown\n"
|
|
" --rlimit-nofile=<num> set maximum number of file descriptors\n"
|
|
" (0 leaves rlimit unchanged)\n"
|
|
" default: min(1000000, fs.file-max - 16384)\n"
|
|
" if the current rlimit is lower\n"
|
|
" -o allow_direct_io|no_allow_direct_io\n"
|
|
" retain/discard O_DIRECT flags passed down\n"
|
|
" to virtiofsd from guest applications.\n"
|
|
" default: no_allow_direct_io\n"
|
|
" -o announce_submounts Announce sub-mount points to the guest\n"
|
|
" -o posix_acl/no_posix_acl Enable/Disable posix_acl. (default: disabled)\n"
|
|
" -o security_label/no_security_label Enable/Disable security label. (default: disabled)\n"
|
|
" -o killpriv_v2/no_killpriv_v2\n"
|
|
" Enable/Disable FUSE_HANDLE_KILLPRIV_V2.\n"
|
|
" (default: enabled as long as client supports it)\n"
|
|
);
|
|
}
|
|
|
|
static int fuse_helper_opt_proc(void *data, const char *arg, int key,
|
|
struct fuse_args *outargs)
|
|
{
|
|
(void)data;
|
|
(void)outargs;
|
|
|
|
switch (key) {
|
|
case FUSE_OPT_KEY_NONOPT:
|
|
fuse_log(FUSE_LOG_ERR, "fuse: invalid argument `%s'\n", arg);
|
|
return -1;
|
|
|
|
default:
|
|
/* Pass through unknown options */
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
static unsigned long get_default_rlimit_nofile(void)
|
|
{
|
|
g_autofree gchar *file_max_str = NULL;
|
|
const rlim_t reserved_fds = 16384; /* leave at least this many fds free */
|
|
rlim_t max_fds = 1000000; /* our default RLIMIT_NOFILE target */
|
|
rlim_t file_max;
|
|
struct rlimit rlim;
|
|
|
|
/*
|
|
* Reduce max_fds below the system-wide maximum, if necessary. This
|
|
* ensures there are fds available for other processes so we don't
|
|
* cause resource exhaustion.
|
|
*/
|
|
if (!g_file_get_contents("/proc/sys/fs/file-max", &file_max_str,
|
|
NULL, NULL)) {
|
|
fuse_log(FUSE_LOG_ERR, "can't read /proc/sys/fs/file-max\n");
|
|
exit(1);
|
|
}
|
|
file_max = g_ascii_strtoull(file_max_str, NULL, 10);
|
|
if (file_max < 2 * reserved_fds) {
|
|
fuse_log(FUSE_LOG_ERR,
|
|
"The fs.file-max sysctl is too low (%lu) to allow a "
|
|
"reasonable number of open files.\n",
|
|
(unsigned long)file_max);
|
|
exit(1);
|
|
}
|
|
max_fds = MIN(file_max - reserved_fds, max_fds);
|
|
|
|
if (getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
|
|
fuse_log(FUSE_LOG_ERR, "getrlimit(RLIMIT_NOFILE): %m\n");
|
|
exit(1);
|
|
}
|
|
|
|
if (rlim.rlim_cur >= max_fds) {
|
|
return 0; /* we have more fds available than required! */
|
|
}
|
|
return max_fds;
|
|
}
|
|
|
|
int fuse_parse_cmdline(struct fuse_args *args, struct fuse_cmdline_opts *opts)
|
|
{
|
|
memset(opts, 0, sizeof(struct fuse_cmdline_opts));
|
|
|
|
opts->max_idle_threads = 10;
|
|
opts->rlimit_nofile = get_default_rlimit_nofile();
|
|
opts->foreground = 1;
|
|
|
|
if (fuse_opt_parse(args, opts, fuse_helper_opts, fuse_helper_opt_proc) ==
|
|
-1) {
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
int fuse_daemonize(int foreground)
|
|
{
|
|
int ret = 0, rett;
|
|
if (!foreground) {
|
|
int nullfd;
|
|
int waiter[2];
|
|
char completed;
|
|
|
|
if (!g_unix_open_pipe(waiter, FD_CLOEXEC, NULL)) {
|
|
fuse_log(FUSE_LOG_ERR, "fuse_daemonize: pipe: %s\n",
|
|
strerror(errno));
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* demonize current process by forking it and killing the
|
|
* parent. This makes current process as a child of 'init'.
|
|
*/
|
|
switch (fork()) {
|
|
case -1:
|
|
fuse_log(FUSE_LOG_ERR, "fuse_daemonize: fork: %s\n",
|
|
strerror(errno));
|
|
return -1;
|
|
case 0:
|
|
break;
|
|
default:
|
|
_exit(read(waiter[0], &completed,
|
|
sizeof(completed) != sizeof(completed)));
|
|
}
|
|
|
|
if (setsid() == -1) {
|
|
fuse_log(FUSE_LOG_ERR, "fuse_daemonize: setsid: %s\n",
|
|
strerror(errno));
|
|
return -1;
|
|
}
|
|
|
|
ret = chdir("/");
|
|
|
|
nullfd = open("/dev/null", O_RDWR, 0);
|
|
if (nullfd != -1) {
|
|
rett = dup2(nullfd, 0);
|
|
if (!ret) {
|
|
ret = rett;
|
|
}
|
|
rett = dup2(nullfd, 1);
|
|
if (!ret) {
|
|
ret = rett;
|
|
}
|
|
rett = dup2(nullfd, 2);
|
|
if (!ret) {
|
|
ret = rett;
|
|
}
|
|
if (nullfd > 2) {
|
|
close(nullfd);
|
|
}
|
|
}
|
|
|
|
/* Propagate completion of daemon initialization */
|
|
completed = 1;
|
|
rett = write(waiter[1], &completed, sizeof(completed));
|
|
if (!ret) {
|
|
ret = rett;
|
|
}
|
|
close(waiter[0]);
|
|
close(waiter[1]);
|
|
} else {
|
|
ret = chdir("/");
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
void fuse_apply_conn_info_opts(struct fuse_conn_info_opts *opts,
|
|
struct fuse_conn_info *conn)
|
|
{
|
|
if (opts->set_max_write) {
|
|
conn->max_write = opts->max_write;
|
|
}
|
|
if (opts->set_max_background) {
|
|
conn->max_background = opts->max_background;
|
|
}
|
|
if (opts->set_congestion_threshold) {
|
|
conn->congestion_threshold = opts->congestion_threshold;
|
|
}
|
|
if (opts->set_time_gran) {
|
|
conn->time_gran = opts->time_gran;
|
|
}
|
|
if (opts->set_max_readahead) {
|
|
conn->max_readahead = opts->max_readahead;
|
|
}
|
|
|
|
#define LL_ENABLE(cond, cap) \
|
|
if (cond) \
|
|
conn->want |= (cap)
|
|
#define LL_DISABLE(cond, cap) \
|
|
if (cond) \
|
|
conn->want &= ~(cap)
|
|
|
|
LL_ENABLE(opts->splice_read, FUSE_CAP_SPLICE_READ);
|
|
LL_DISABLE(opts->no_splice_read, FUSE_CAP_SPLICE_READ);
|
|
|
|
LL_ENABLE(opts->splice_write, FUSE_CAP_SPLICE_WRITE);
|
|
LL_DISABLE(opts->no_splice_write, FUSE_CAP_SPLICE_WRITE);
|
|
|
|
LL_ENABLE(opts->splice_move, FUSE_CAP_SPLICE_MOVE);
|
|
LL_DISABLE(opts->no_splice_move, FUSE_CAP_SPLICE_MOVE);
|
|
|
|
LL_ENABLE(opts->auto_inval_data, FUSE_CAP_AUTO_INVAL_DATA);
|
|
LL_DISABLE(opts->no_auto_inval_data, FUSE_CAP_AUTO_INVAL_DATA);
|
|
|
|
LL_DISABLE(opts->no_readdirplus, FUSE_CAP_READDIRPLUS);
|
|
LL_DISABLE(opts->no_readdirplus_auto, FUSE_CAP_READDIRPLUS_AUTO);
|
|
|
|
LL_ENABLE(opts->async_dio, FUSE_CAP_ASYNC_DIO);
|
|
LL_DISABLE(opts->no_async_dio, FUSE_CAP_ASYNC_DIO);
|
|
|
|
LL_ENABLE(opts->writeback_cache, FUSE_CAP_WRITEBACK_CACHE);
|
|
LL_DISABLE(opts->no_writeback_cache, FUSE_CAP_WRITEBACK_CACHE);
|
|
|
|
LL_ENABLE(opts->async_read, FUSE_CAP_ASYNC_READ);
|
|
LL_DISABLE(opts->sync_read, FUSE_CAP_ASYNC_READ);
|
|
|
|
LL_DISABLE(opts->no_remote_posix_lock, FUSE_CAP_POSIX_LOCKS);
|
|
LL_DISABLE(opts->no_remote_flock, FUSE_CAP_FLOCK_LOCKS);
|
|
}
|
|
|
|
struct fuse_conn_info_opts *fuse_parse_conn_info_opts(struct fuse_args *args)
|
|
{
|
|
struct fuse_conn_info_opts *opts;
|
|
|
|
opts = calloc(1, sizeof(struct fuse_conn_info_opts));
|
|
if (opts == NULL) {
|
|
fuse_log(FUSE_LOG_ERR, "calloc failed\n");
|
|
return NULL;
|
|
}
|
|
if (fuse_opt_parse(args, opts, conn_info_opt_spec, NULL) == -1) {
|
|
free(opts);
|
|
return NULL;
|
|
}
|
|
return opts;
|
|
}
|