Files
tromcho.net/src/client/ublk_server.cpp
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907 lines
30 KiB
C++

// Copyright (c) Vitaliy Filippov, 2019+
// License: VNPL-1.1 (see README.md for details)
// ublk-based Vitastor block device in userspace
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <dirent.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/mman.h>
#include <unistd.h>
#include "../liburing/include/ublk_cmd.h"
#include "cluster_client.h"
#include "epoll_manager.h"
#include "str_util.h"
const char *exe_name = NULL;
const char *help_text =
"Vitastor ublk server " VITASTOR_VERSION "\n"
"(c) Vitaliy Filippov, 2025+ (VNPL-1.1)\n"
"\n"
"COMMANDS:\n"
"\n"
"vitastor-ublk map [OPTIONS] (--image <image> | --pool <pool> --inode <inode> --size <size in bytes>)\n"
" Map a ublk device. Options:\n"
" --recover\n"
" Recover a mapped device if the previous ublk server is dead.\n"
" --queue_depth 256\n"
" Maximum queue size for the device.\n"
" --max_io_size 1M\n"
" Maximum single I/O size for the device. Default: max(1 MB, pool block size * EC part count).\n"
" --readonly\n"
" Make the device read-only.\n"
" --hdd\n"
" Mark the device as rotational.\n"
" --dev_num N\n"
" Use the specified device /dev/ublkbN instead of automatic selection (alternative syntax\n"
" to /dev/ublkbN positional parameter).\n"
" --pidfile /run/ublk_pid_file.pid\n"
" Write process ID to the specified file.\n"
" --logfile /path/to/log/file.txt\n"
" Write log messages to the specified file instead of dropping them (in background mode)\n"
" or printing them to the standard output (in foreground mode).\n"
" --foreground 1\n"
" Stay in foreground, do not daemonize.\n"
"\n"
"vitastor-ublk unmap [--force] /dev/ublkb<N>\n"
" Unmap a Vitastor ublk device. Do not check if it's actually mapped if --force is specified.\n"
"\n"
"vitastor-ublk ls [--json]\n"
" List mapped Vitastor ublk devices, optionally in JSON format.\n"
"\n"
"Use vitastor-ublk --help <command> for command details or vitastor-ublk --help --all for all details.\n"
"\n"
"All usual Vitastor config options like --config_path <path_to_config> may also be specified in CLI.\n"
;
class ublk_server
{
protected:
std::string image_name;
uint64_t inode = 0;
uint64_t device_size = 0;
int req_dev_num = -1;
bool readonly = false;
bool hdd = false;
bool recover = false;
uint16_t queue_depth = 256;
uint32_t max_io_size = 0;
ring_loop_t *ringloop = NULL;
epoll_manager_t *epmgr = NULL;
cluster_client_t *cli = NULL;
inode_watch_t *watch = NULL;
std::string logfile = "/dev/null";
std::string pidfile;
public:
ublk_server()
{
ringloop = new ring_loop_t(RINGLOOP_DEFAULT_SIZE, false, true);
}
~ublk_server()
{
if (ctrl_fd >= 0)
{
close(ctrl_fd);
ctrl_fd = -1;
}
if (cdev_fd >= 0)
{
close(cdev_fd);
cdev_fd = -1;
}
for (auto & buf: buffers)
{
free(buf);
}
buffers.clear();
if (ringloop)
{
delete ringloop;
ringloop = NULL;
}
}
static json11::Json::object parse_args(int narg, const char *args[])
{
json11::Json::object cfg;
int pos = 0;
for (int i = 1; i < narg; i++)
{
if (!strcmp(args[i], "-h") || !strcmp(args[i], "--help"))
{
cfg["help"] = 1;
}
else if (args[i][0] == '-' && args[i][1] == '-')
{
const char *opt = args[i]+2;
cfg[opt] = !strcmp(opt, "json") || !strcmp(opt, "all") ||
!strcmp(opt, "readonly") || !strcmp(opt, "hdd") || !strcmp(opt, "recover") ||
!strcmp(opt, "force") || i == narg-1 ? "1" : args[++i];
}
else if (pos == 0)
{
cfg["command"] = args[i];
pos++;
}
else if (pos == 1)
{
char c = 0;
int n = 0;
if (sscanf(args[i], "/dev/ublkb%d%c", &n, &c) == 1)
cfg["dev_num"] = n;
else if (sscanf(args[i], "/dev/ublkc%d%c", &n, &c) == 1)
cfg["dev_num"] = n;
else
cfg["dev_num"] = args[i];
pos++;
}
}
return cfg;
}
void exec(json11::Json cfg)
{
if (cfg["help"].bool_value())
{
goto help;
}
if (cfg["command"] == "map")
{
start(cfg);
}
else if (cfg["command"] == "unmap")
{
if (!cfg["dev_num"].is_number() &&
cfg["dev_num"].string_value() != "0" &&
!cfg["dev_num"].uint64_value())
{
fprintf(stderr, "device name or number is missing\n");
exit(1);
}
open_control();
unmap_device(cfg["dev_num"].uint64_value(), cfg["unpriv"].bool_value(), cfg["wait"].bool_value());
}
else if (cfg["command"] == "ls" || cfg["command"] == "list" || cfg["command"] == "list-mapped")
{
auto mapped = list_mapped();
print_mapped(mapped, !cfg["json"].is_null());
}
else
{
help:
print_help(help_text, "vitastor-ublk", cfg["command"].string_value(), cfg["all"].bool_value());
exit(0);
}
}
void start(json11::Json cfg)
{
// Check options
if (cfg["dev_num"].string_value() != "" || cfg["dev_num"].is_number())
{
req_dev_num = cfg["dev_num"].uint64_value();
}
if (cfg["image"].string_value() != "")
{
// Use image name
image_name = cfg["image"].string_value();
inode = 0;
}
else
{
// Use pool, inode number and size
device_size = cfg["size"].is_string()
? parse_size(cfg["size"].string_value())
: cfg["size"].uint64_value();
if (!device_size)
{
fprintf(stderr, "device size is missing\n");
exit(1);
}
inode = cfg["inode"].uint64_value();
uint64_t pool = cfg["pool"].uint64_value();
if (pool)
{
inode = INODE_WITH_POOL(pool, inode);
}
if (!INODE_POOL(inode))
{
fprintf(stderr, "pool is missing\n");
exit(1);
}
}
if (cfg["client_writeback_allowed"].is_null())
{
// ublk is always aware of fsync, so we allow write-back cache
// by default if it's enabled
auto obj = cfg.object_items();
obj["client_writeback_allowed"] = true;
cfg = obj;
}
readonly = cfg["readonly"].bool_value();
hdd = cfg["hdd"].bool_value();
recover = cfg["recover"].bool_value();
if (recover && req_dev_num < 0)
{
fprintf(stderr, "device is missing\n");
exit(1);
}
// Create client
epmgr = new epoll_manager_t(ringloop);
cli = new cluster_client_t(ringloop, epmgr->tfd, cfg);
// cli->config contains merged config
if (!cfg["queue_depth"].is_null())
{
queue_depth = cfg["queue_depth"].uint64_value();
}
else if (cli->config.find("ublk_queue_depth") != cli->config.end())
{
queue_depth = cli->config["ublk_queue_depth"].uint64_value();
}
if (!cfg["max_io_size"].is_null())
{
max_io_size = parse_size(cfg["max_io_size"].string_value());
}
else if (cli->config.find("ublk_max_io_size") != cli->config.end())
{
max_io_size = cli->config["ublk_max_io_size"].is_string()
? parse_size(cli->config["ublk_max_io_size"].string_value())
: cli->config["ublk_max_io_size"].uint64_value();
}
// Load image metadata
while (!cli->is_ready())
{
ringloop->loop();
if (cli->is_ready())
break;
ringloop->wait();
}
if (!inode)
{
watch = cli->st_cli.watch_inode(image_name);
device_size = watch->cfg.size;
if (!watch->cfg.num || !device_size)
{
// Image does not exist
fprintf(stderr, "Image %s does not exist\n", image_name.c_str());
exit(1);
}
}
const bool writeback = cli->get_immediate_commit(inode);
auto pool_it = cli->st_cli.pool_config.find(INODE_POOL(inode ? inode : watch->cfg.num));
if (pool_it == cli->st_cli.pool_config.end())
{
fprintf(stderr, "Pool %u does not exist\n", INODE_POOL(inode ? inode : watch->cfg.num));
exit(1);
}
auto & pool_cfg = pool_it->second;
uint32_t pg_data_size = pool_cfg.data_block_size * (pool_cfg.scheme == POOL_SCHEME_REPLICATED
? 1 : pool_cfg.pg_size-pool_cfg.parity_chunks);
if (max_io_size & (max_io_size-1))
{
fprintf(stderr, "max_io_size must be a power of 2\n");
exit(1);
}
uint32_t buf_size = max_io_size ? max_io_size : (1024*1024 < pg_data_size ? pg_data_size : 1024*1024);
uint32_t bitmap_granularity = pool_cfg.bitmap_granularity;
load_module();
bool bg = cfg["foreground"].is_null();
logfile = cfg["logfile"].string_value();
pidfile = cfg["pidfile"].string_value();
open_control();
if (recover)
{
recover_device(req_dev_num);
}
else
{
add_device(
req_dev_num,
(writeback ? UBLK_ATTR_VOLATILE_CACHE : 0) |
(readonly ? UBLK_ATTR_READ_ONLY : 0) | (hdd ? UBLK_ATTR_ROTATIONAL : 0),
queue_depth, bitmap_granularity, buf_size, pg_data_size, device_size
);
}
int notifyfd[2] = { -1, -1 };
if (bg)
{
if (socketpair(AF_UNIX, SOCK_STREAM, 0, notifyfd) < 0)
{
perror("socketpair");
exit(1);
}
daemonize_fork(notifyfd);
close(notifyfd[0]);
}
start_device(recover);
if (pidfile != "")
write_pid();
if (bg)
{
daemonize_reopen_stdio();
int ok = 0;
(void)write(notifyfd[1], &ok, sizeof(ok));
close(notifyfd[1]);
}
else
printf("/dev/ublkb%d\n", ublk_dev.dev_id);
stop = false;
while (!stop)
{
ringloop->loop();
ringloop->wait();
}
cli->flush();
delete cli;
delete epmgr;
cli = NULL;
epmgr = NULL;
}
void load_module()
{
if (access("/sys/module/ublk_drv", F_OK) == 0)
{
return;
}
int r;
if ((r = system("modprobe ublk_drv")) != 0)
{
if (r < 0)
perror("Failed to load ublk_drv kernel module");
else
fprintf(stderr, "Failed to load ublk_drv kernel module\n");
exit(1);
}
}
void daemonize_fork(int *notifyfd)
{
if (fork())
{
// Parent - check status
close(notifyfd[1]);
int child_errno = 1;
(void)read(notifyfd[0], &child_errno, sizeof(child_errno));
if (!child_errno)
printf("/dev/ublkb%d\n", ublk_dev.dev_id);
exit(child_errno);
}
setsid();
if (fork())
exit(0);
}
void daemonize_reopen_stdio()
{
close(0);
close(1);
close(2);
open("/dev/null", O_RDONLY);
open(logfile.c_str(), O_WRONLY|O_APPEND|O_CREAT, 0666);
open(logfile.c_str(), O_WRONLY|O_APPEND|O_CREAT, 0666);
if (chdir("/") != 0)
fprintf(stderr, "Warning: Failed to chdir into /\n");
}
void write_pid()
{
int fd = open(pidfile.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0666);
if (fd < 0)
{
fprintf(stderr, "Failed to create pid file %s: %s (code %d)\n", pidfile.c_str(), strerror(errno), errno);
return;
}
auto pid = std::to_string(getpid());
if (write(fd, pid.c_str(), pid.size()) < 0)
{
fprintf(stderr, "Failed to write pid to %s: %s (code %d)\n", pidfile.c_str(), strerror(errno), errno);
}
close(fd);
}
json11::Json::object list_mapped()
{
int n_in_dev = 0;
DIR *d = opendir("/dev");
if (!d)
{
fprintf(stderr, "Failed to list /dev: %s (code %d)\n", strerror(errno), errno);
exit(1);
}
dirent *ent;
while ((ent = readdir(d)) != NULL)
{
if (!strncmp(ent->d_name, "ublkc", strlen("ublkc")))
n_in_dev++;
}
closedir(d);
json11::Json::object mapped;
const char *self_filename = exe_name;
for (int i = 0; exe_name[i] != 0; i++)
{
if (exe_name[i] == '/')
self_filename = exe_name+i+1;
}
char path[64] = { 0 };
int dev_num = -1, n_in_ctrl = 0;
open_control();
while (true)
{
dev_num++;
int res = get_dev_info(dev_num, false);
if (res == -ENODEV)
{
if (n_in_ctrl >= n_in_dev)
break;
continue;
}
n_in_ctrl++;
sprintf(path, "/proc/%d/cmdline", ublk_dev.ublksrv_pid);
std::string cmdline = read_file(path);
if (cmdline == "")
{
// Process is dead
mapped["/dev/ublkb"+std::to_string(dev_num)] = json11::Json::object{{"dead", true}};
continue;
}
std::vector<const char*> argv;
int last = 0;
for (int i = 0; i < cmdline.size(); i++)
{
if (cmdline[i] == 0)
{
argv.push_back(cmdline.c_str()+last);
last = i+1;
}
}
if (argv.size() > 0)
{
const char *pid_filename = argv[0];
for (int i = 0; argv[0][i] != 0; i++)
{
if (argv[0][i] == '/')
pid_filename = argv[0]+i+1;
}
if (!strcmp(pid_filename, self_filename))
{
json11::Json::object cfg = ublk_server::parse_args(argv.size(), argv.data());
if (cfg["command"] == "map")
{
cfg.erase("command");
cfg["pid"] = ublk_dev.ublksrv_pid;
mapped["/dev/ublkb"+std::to_string(dev_num)] = cfg;
}
}
}
}
return mapped;
}
void print_mapped(json11::Json mapped, bool json)
{
if (json)
{
printf("%s\n", mapped.dump().c_str());
}
else
{
for (auto & dev: mapped.object_items())
{
printf("%s\n", dev.first.c_str());
for (auto & k: dev.second.object_items())
{
printf("%s: %s\n", k.first.c_str(), k.second.as_string().c_str());
}
printf("\n");
}
}
}
std::string read_file(char *path)
{
int fd = open(path, O_RDONLY);
if (fd < 0)
{
if (errno == ENOENT)
return "";
auto err = "open "+std::string(path);
perror(err.c_str());
exit(1);
}
std::string r;
while (true)
{
int l = r.size();
r.resize(l + 1024);
int rd = read(fd, (void*)(r.c_str() + l), 1024);
if (rd <= 0)
{
r.resize(l);
break;
}
r.resize(l + rd);
}
close(fd);
return r;
}
protected:
bool stop = false;
bool new_opcodes = true;
uint64_t ublk_features = 0;
int max_wait_time_ms = 5000;
int ctrl_fd = -1, cdev_fd = -1;
ublksrv_ctrl_dev_info ublk_dev = {};
ublksrv_io_desc *ublk_queue = NULL;
std::vector<uint8_t*> buffers;
void open_control()
{
ctrl_fd = open("/dev/ublk-control", O_RDWR);
if (ctrl_fd < 0)
{
fprintf(stderr, "Failed to open /dev/ublk-control: %s (code %d)\n", strerror(errno), errno);
exit(1);
}
// Check features
int res = sync_ublk_cmd(UBLK_U_CMD_GET_FEATURES, &ublk_features, 8, 0);
if (res == -EOPNOTSUPP)
{
new_opcodes = false;
}
else if (res != 0)
{
fprintf(stderr, "Failed to get ublk features: %s (code %d)\n", strerror(-res), res);
exit(1);
}
}
void add_device(int32_t dev_num, uint32_t attrs, uint16_t queue_depth, uint32_t phys_block_size,
uint32_t max_io_buf_bytes, uint64_t opt_block_size, uint64_t device_size)
{
// Add device
ublk_dev.dev_id = dev_num;
ublk_dev.nr_hw_queues = 1;
ublk_dev.queue_depth = queue_depth;
ublk_dev.max_io_buf_bytes = max_io_buf_bytes;
ublk_dev.flags = UBLK_F_USER_RECOVERY | UBLK_F_USER_RECOVERY_REISSUE;
int res = sync_ublk_cmd(new_opcodes ? UBLK_U_CMD_ADD_DEV : UBLK_CMD_ADD_DEV, &ublk_dev, sizeof(ublk_dev));
if (res != 0)
{
fprintf(stderr, "Failed to add ublk device: %s (code %d)\n", strerror(-res), res);
exit(1);
}
// Wait until the device appears
std::string ublkc_path = "/dev/ublkc"+std::to_string(ublk_dev.dev_id);
int wait_time = 0;
while (wait_time < max_wait_time_ms)
{
cdev_fd = open(ublkc_path.c_str(), O_RDWR);
if (cdev_fd >= 0)
break;
else if (errno != ENOENT)
{
fprintf(stderr, "Failed to open %s: %s (code %d)", ublkc_path.c_str(), strerror(errno), errno);
exit(1);
}
usleep(100);
wait_time += 100;
}
close(cdev_fd);
cdev_fd = -1;
// Set device params
uint8_t io_opt_shift = 0;
while ((opt_block_size >> io_opt_shift) > 1)
{
io_opt_shift++;
}
uint8_t phys_shift = 0;
while ((phys_block_size >> phys_shift) > 1)
{
phys_shift++;
}
ublk_params params = {
.len = sizeof(ublk_params),
.types = UBLK_PARAM_TYPE_BASIC,
.basic = {
.attrs = attrs, // UBLK_ATTR_READ_ONLY | UBLK_ATTR_ROTATIONAL | UBLK_ATTR_VOLATILE_CACHE | UBLK_ATTR_FUA
.logical_bs_shift = phys_shift,
.physical_bs_shift = phys_shift,
.io_opt_shift = io_opt_shift,
.io_min_shift = phys_shift,
.max_sectors = max_io_buf_bytes / 512,
.chunk_sectors = 0,
.dev_sectors = device_size / 512,
.virt_boundary_mask = 0,
},
.discard = {
.discard_alignment = 0,
.discard_granularity = 0,
.max_discard_sectors = 0,
.max_write_zeroes_sectors = 0,
.max_discard_segments = 0,
},
};
res = sync_unpriv_cmd(false, new_opcodes ? UBLK_U_CMD_SET_PARAMS : UBLK_CMD_SET_PARAMS, &params, sizeof(params));
if (res != 0)
{
fprintf(stderr, "Failed to set ublk device params: %s (code %d)\n", strerror(-res), res);
exit(1);
}
}
void map_ublk_queue()
{
const unsigned page_sz = getpagesize();
size_t cmd_buf_size = (ublk_dev.queue_depth * sizeof(ublksrv_io_desc) + page_sz-1) / page_sz * page_sz;
//const unsigned queue_offset = (UBLK_MAX_QUEUE_DEPTH * sizeof(ublksrv_io_desc) + page_sz-1) / page_sz * page_sz;
//off = q_id * queue_offset;
ublk_queue = (ublksrv_io_desc*)mmap(0, cmd_buf_size, PROT_READ, MAP_SHARED | MAP_POPULATE, cdev_fd, 0);
if ((void*)ublk_queue == MAP_FAILED)
{
fprintf(stderr, "Failed to mmap() ublk queue buffer\n");
exit(1);
}
}
void recover_device(uint32_t dev_num)
{
ublk_dev.dev_id = dev_num;
int res = sync_ublk_cmd(new_opcodes ? UBLK_U_CMD_GET_DEV_INFO : UBLK_CMD_GET_DEV_INFO, &ublk_dev, sizeof(ublk_dev));
if (res != 0)
{
fprintf(stderr, "Failed to get /dev/ublkb%u device info: %s (code %d)\n", dev_num, strerror(-res), res);
exit(1);
}
if (ublk_dev.nr_hw_queues != 1)
{
fprintf(stderr, "Device /dev/ublkb%u is not supported because it has %d queues\n", dev_num, ublk_dev.nr_hw_queues);
exit(1);
}
if (ublk_dev.ublksrv_pid != 0)
{
res = kill(ublk_dev.ublksrv_pid, 0);
if (res == 0)
{
fprintf(stderr, "Device /dev/ublkb%u is still alive, daemon PID is %u\n", dev_num, ublk_dev.ublksrv_pid);
exit(1);
}
else if (errno != ESRCH)
{
fprintf(stderr, "Device /dev/ublkb%u is still alive, failed to check if the daemon with PID %u is running: %s (code %d)\n",
dev_num, ublk_dev.ublksrv_pid, strerror(errno), errno);
exit(1);
}
}
// Send the "start recovery" command
res = sync_unpriv_cmd(false, new_opcodes ? UBLK_U_CMD_START_USER_RECOVERY : UBLK_CMD_START_USER_RECOVERY, NULL, 0);
if (res != 0)
{
fprintf(stderr, "Failed to start /dev/ublkb%u device recovery: %s (code %d)\n", dev_num, strerror(-res), res);
exit(1);
}
}
void start_device(bool recover)
{
std::string ublkc_path = "/dev/ublkc"+std::to_string(ublk_dev.dev_id);
cdev_fd = open(ublkc_path.c_str(), O_RDWR|O_NONBLOCK);
if (cdev_fd < 0)
{
fprintf(stderr, "Failed to open %s: %s (code %d)", ublkc_path.c_str(), strerror(errno), errno);
exit(1);
}
// FIXME Here we could optionally do ublk_get_queue_affinity
// Map queue command buffer
map_ublk_queue();
// submit initial fetch requests to ublk driver
for (int i = 0; i < ublk_dev.queue_depth; i++)
{
buffers.push_back((uint8_t*)memalign_or_die(MEM_ALIGNMENT, ublk_dev.max_io_buf_bytes));
submit_request(new_opcodes ? UBLK_U_IO_FETCH_REQ : UBLK_IO_FETCH_REQ, i, 0);
}
ringloop->submit();
// start device
ublk_dev.ublksrv_pid = getpid();
int res = sync_unpriv_cmd(false, (recover
? (new_opcodes ? UBLK_U_CMD_END_USER_RECOVERY : UBLK_CMD_END_USER_RECOVERY)
: (new_opcodes ? UBLK_U_CMD_START_DEV : UBLK_CMD_START_DEV)), NULL, 0, ublk_dev.ublksrv_pid);
if (res != 0)
{
fprintf(stderr, "Failed to start ublk device: %s (code %d)\n", strerror(-res), res);
exit(1);
}
close(ctrl_fd);
ctrl_fd = -1;
}
void submit_request(uint64_t ublk_cmd, int i, int res)
{
io_uring_sqe *sqe = ringloop->get_sqe();
ring_data_t* data = ((ring_data_t*)sqe->user_data);
sqe->fd = cdev_fd;
sqe->opcode = IORING_OP_URING_CMD;
//sqe->flags = IOSQE_FIXED_FILE;
sqe->flags = 0;
sqe->rw_flags = 0;
sqe->off = ublk_cmd;
ublksrv_io_cmd *cmd = (ublksrv_io_cmd *)&sqe->addr3; // sqe128 command buffer address
cmd->q_id = 0;
cmd->tag = i;
cmd->addr = (uint64_t)buffers[i];
cmd->result = res;
data->callback = [this, i](ring_data_t *data) { exec_request(data->res, i); };
}
void exec_request(int res, int i)
{
if (res != 0)
{
// Note: res may be also UBLK_IO_RES_NEED_GET_DATA if UBLK_F_NEED_GET_DATA is enabled,
// in this case you should submit_request(UBLK_IO_NEED_GET_DATA, i) again with buffer
if (res == -ENODEV)
{
// ublk device is removed
stop = true;
return;
}
fprintf(stderr, "Fetching ublk request failed: %s (code %d)\n", strerror(-res), res);
exit(1);
}
ublksrv_io_desc *iod = &ublk_queue[i];
uint8_t opcode = ublksrv_get_op(iod);
if (opcode == UBLK_IO_OP_FLUSH)
{
cluster_op_t *op = new cluster_op_t;
op->opcode = OSD_OP_SYNC;
op->callback = [this, i](cluster_op_t *op)
{
submit_request(new_opcodes ? UBLK_U_IO_COMMIT_AND_FETCH_REQ : UBLK_IO_COMMIT_AND_FETCH_REQ, i, op->retval);
delete op;
};
cli->execute(op);
}
else if (opcode == UBLK_IO_OP_WRITE_ZEROES || opcode == UBLK_IO_OP_DISCARD)
{
submit_request(new_opcodes ? UBLK_U_IO_COMMIT_AND_FETCH_REQ : UBLK_IO_COMMIT_AND_FETCH_REQ, i, -EINVAL);
}
else if (opcode == UBLK_IO_OP_READ || opcode == UBLK_IO_OP_WRITE)
{
cluster_op_t *op = new cluster_op_t;
op->opcode = opcode == UBLK_IO_OP_READ ? OSD_OP_READ : OSD_OP_WRITE;
op->inode = inode ? inode : watch->cfg.num;
op->offset = iod->start_sector * 512;
op->len = iod->nr_sectors * 512;
op->iov.push_back(buffers[i], op->len);
op->callback = [this, i](cluster_op_t *op)
{
submit_request(new_opcodes ? UBLK_U_IO_COMMIT_AND_FETCH_REQ : UBLK_IO_COMMIT_AND_FETCH_REQ, i, op->retval);
delete op;
};
cli->execute(op);
}
else
{
submit_request(new_opcodes ? UBLK_U_IO_COMMIT_AND_FETCH_REQ : UBLK_IO_COMMIT_AND_FETCH_REQ, i, -EINVAL);
}
}
int get_dev_info(int dev_num, bool unpriv)
{
// Get device info
ublk_dev.dev_id = dev_num;
int res = unpriv
? sync_unpriv_cmd(true, new_opcodes ? UBLK_U_CMD_GET_DEV_INFO2 : UBLK_CMD_GET_DEV_INFO2, &ublk_dev, sizeof(ublk_dev))
: sync_ublk_cmd(new_opcodes ? UBLK_U_CMD_GET_DEV_INFO : UBLK_CMD_GET_DEV_INFO, &ublk_dev, sizeof(ublk_dev));
if (res != 0 && res != -ENODEV)
{
fprintf(stderr, "Failed to get device info from /dev/ublkc%d: %s (code %d)\n", dev_num, strerror(-res), res);
exit(1);
}
return res;
}
void unmap_device(int dev_num, bool unpriv, bool wait)
{
int res = 0;
// Stop the device
ublk_dev.dev_id = dev_num;
res = sync_unpriv_cmd(unpriv, new_opcodes ? UBLK_U_CMD_STOP_DEV : UBLK_CMD_STOP_DEV, NULL, 0);
if (res != 0)
{
fprintf(stderr, "Failed to stop device /dev/ublkc%d: %s (code %d)\n", dev_num, strerror(-res), res);
exit(1);
}
// Delete the device
res = sync_unpriv_cmd(unpriv, new_opcodes ? (wait ? UBLK_U_CMD_DEL_DEV : UBLK_U_CMD_DEL_DEV_ASYNC) : UBLK_CMD_DEL_DEV, NULL, 0);
if (res != 0)
{
fprintf(stderr, "Failed to delete device /dev/ublkc%d: %s (code %d)\n", dev_num, strerror(-res), res);
exit(1);
}
}
int sync_unpriv_cmd(bool unpriv, uint32_t cmd_op, void *addr, uint32_t len, uint64_t data0 = 0)
{
int res;
if (unpriv)
{
static const int path_max = 64;
char buf[path_max + len];
memset(buf, 0, path_max);
memcpy(buf + path_max, addr, len);
snprintf(buf, path_max, "/dev/ublkc%d", ublk_dev.dev_id);
res = sync_ublk_cmd(cmd_op, buf, sizeof(buf), path_max, data0);
if (!res)
memcpy(addr, buf + path_max, len);
}
else
{
res = sync_ublk_cmd(cmd_op, addr, len, 0, data0);
}
return res;
}
int sync_ublk_cmd(uint32_t cmd_op, void *addr, uint32_t len, uint16_t dev_path_len = 0, uint64_t data0 = 0)
{
io_uring_sqe *sqe = ringloop->get_sqe();
sqe->fd = ctrl_fd;
sqe->opcode = IORING_OP_URING_CMD;
sqe->ioprio = 0;
sqe->off = cmd_op;
ublksrv_ctrl_cmd *cmd = (ublksrv_ctrl_cmd *)&sqe->addr3; // sqe128 command buffer address
cmd->dev_id = ublk_dev.dev_id;
cmd->queue_id = -1;
cmd->addr = (uint64_t)addr;
cmd->len = len;
cmd->data[0] = data0;
cmd->dev_path_len = dev_path_len;
ring_data_t* data = ((ring_data_t*)sqe->user_data);
bool done = false;
int res = 0;
data->callback = [&](ring_data_t *data)
{
res = data->res;
done = true;
};
ringloop->submit();
while (!done)
{
ringloop->loop();
if (!done)
ringloop->wait();
}
return res;
}
};
int main(int narg, const char *args[])
{
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
exe_name = args[0];
ublk_server *p = new ublk_server();
p->exec(ublk_server::parse_args(narg, args));
delete p;
return 0;
}