freebsd-nq/sbin/ggate/ggatel/ggatel.c
Pawel Jakub Dawidek 0618f3dcba Fix a deadlock in ggatel(8) simlar to one which was fixed some time
ago in md(4).

Submitted by:	Ivan Voras <ivoras@fer.hr>
2004-10-02 16:58:33 +00:00

319 lines
7.5 KiB
C

/*-
* Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <err.h>
#include <errno.h>
#include <assert.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/bio.h>
#include <sys/disk.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/syslog.h>
#include <geom/gate/g_gate.h>
#include "ggate.h"
enum { UNSET, ATTACH, CREATE, DESTROY, LIST } action = UNSET;
static const char *path = NULL;
static int unit = -1;
static unsigned flags = 0;
static int force = 0;
static unsigned queue_size = G_GATE_QUEUE_SIZE;
static unsigned sectorsize = 0;
static unsigned timeout = G_GATE_TIMEOUT;
static void
usage(void)
{
fprintf(stderr, "usage: %s create [-v] [-o <ro|wo|rw>] [-q queue_size] "
"[-s sectorsize] [-t timeout] [-u unit] <path>\n", getprogname());
fprintf(stderr, " %s attach [-v] [-o <ro|wo|rw>] <-u unit> "
"<path>\n", getprogname());
fprintf(stderr, " %s destroy [-f] <-u unit>\n", getprogname());
fprintf(stderr, " %s list [-v] [-u unit]\n", getprogname());
exit(EXIT_FAILURE);
}
static void
g_gatel_serve(int fd)
{
struct g_gate_ctl_io ggio;
size_t bsize;
if (g_gate_verbose == 0) {
if (daemon(0, 0) == -1) {
g_gate_destroy(unit, 1);
err(EXIT_FAILURE, "Cannot daemonize");
}
}
g_gate_log(LOG_DEBUG, "Worker created: %u.", getpid());
ggio.gctl_version = G_GATE_VERSION;
ggio.gctl_unit = unit;
bsize = sectorsize;
ggio.gctl_data = malloc(bsize);
for (;;) {
int error;
once_again:
ggio.gctl_length = bsize;
ggio.gctl_error = 0;
g_gate_ioctl(G_GATE_CMD_START, &ggio);
error = ggio.gctl_error;
switch (error) {
case 0:
break;
case ECANCELED:
/* Exit gracefully. */
free(ggio.gctl_data);
g_gate_close_device();
close(fd);
exit(EXIT_SUCCESS);
case ENOMEM:
/* Buffer too small. */
assert(ggio.gctl_cmd == BIO_DELETE ||
ggio.gctl_cmd == BIO_WRITE);
ggio.gctl_data = realloc(ggio.gctl_data,
ggio.gctl_length);
if (ggio.gctl_data != NULL) {
bsize = ggio.gctl_length;
goto once_again;
}
/* FALLTHROUGH */
case ENXIO:
default:
g_gate_xlog("ioctl(/dev/%s): %s.", G_GATE_CTL_NAME,
strerror(error));
}
error = 0;
switch (ggio.gctl_cmd) {
case BIO_READ:
if ((size_t)ggio.gctl_length > bsize) {
ggio.gctl_data = realloc(ggio.gctl_data,
ggio.gctl_length);
if (ggio.gctl_data != NULL)
bsize = ggio.gctl_length;
else
error = ENOMEM;
}
if (error == 0) {
if (pread(fd, ggio.gctl_data, ggio.gctl_length,
ggio.gctl_offset) == -1) {
error = errno;
}
}
break;
case BIO_DELETE:
case BIO_WRITE:
if (pwrite(fd, ggio.gctl_data, ggio.gctl_length,
ggio.gctl_offset) == -1) {
error = errno;
}
break;
default:
error = EOPNOTSUPP;
}
ggio.gctl_error = error;
g_gate_ioctl(G_GATE_CMD_DONE, &ggio);
}
}
static void
g_gatel_create(void)
{
struct g_gate_ctl_create ggioc;
int fd;
fd = open(path, g_gate_openflags(flags) | O_DIRECT | O_FSYNC);
if (fd == -1)
err(EXIT_FAILURE, "Cannot open %s", path);
ggioc.gctl_version = G_GATE_VERSION;
ggioc.gctl_unit = unit;
ggioc.gctl_mediasize = g_gate_mediasize(fd);
if (sectorsize == 0)
sectorsize = g_gate_sectorsize(fd);
ggioc.gctl_sectorsize = sectorsize;
ggioc.gctl_timeout = timeout;
ggioc.gctl_flags = flags;
ggioc.gctl_maxcount = queue_size;
strlcpy(ggioc.gctl_info, path, sizeof(ggioc.gctl_info));
g_gate_ioctl(G_GATE_CMD_CREATE, &ggioc);
if (unit == -1)
printf("%s%u\n", G_GATE_PROVIDER_NAME, ggioc.gctl_unit);
unit = ggioc.gctl_unit;
g_gatel_serve(fd);
}
static void
g_gatel_attach(void)
{
int fd;
fd = open(path, g_gate_openflags(flags));
if (fd == -1)
err(EXIT_FAILURE, "Cannot open %s", path);
g_gatel_serve(fd);
}
int
main(int argc, char *argv[])
{
if (argc < 2)
usage();
if (strcasecmp(argv[1], "attach") == 0)
action = ATTACH;
else if (strcasecmp(argv[1], "create") == 0)
action = CREATE;
else if (strcasecmp(argv[1], "destroy") == 0)
action = DESTROY;
else if (strcasecmp(argv[1], "list") == 0)
action = LIST;
else
usage();
argc -= 1;
argv += 1;
for (;;) {
int ch;
ch = getopt(argc, argv, "fo:q:s:t:u:v");
if (ch == -1)
break;
switch (ch) {
case 'f':
if (action != DESTROY)
usage();
force = 1;
break;
case 'o':
if (action != ATTACH && action != CREATE)
usage();
if (strcasecmp("ro", optarg) == 0)
flags = G_GATE_FLAG_READONLY;
else if (strcasecmp("wo", optarg) == 0)
flags = G_GATE_FLAG_WRITEONLY;
else if (strcasecmp("rw", optarg) == 0)
flags = 0;
else {
errx(EXIT_FAILURE,
"Invalid argument for '-o' option.");
}
break;
case 'q':
if (action != CREATE)
usage();
errno = 0;
queue_size = strtoul(optarg, NULL, 10);
if (queue_size == 0 && errno != 0)
errx(EXIT_FAILURE, "Invalid queue_size.");
break;
case 's':
if (action != CREATE)
usage();
errno = 0;
sectorsize = strtoul(optarg, NULL, 10);
if (sectorsize == 0 && errno != 0)
errx(EXIT_FAILURE, "Invalid sectorsize.");
break;
case 't':
if (action != CREATE)
usage();
errno = 0;
timeout = strtoul(optarg, NULL, 10);
if (timeout == 0 && errno != 0)
errx(EXIT_FAILURE, "Invalid timeout.");
break;
case 'u':
errno = 0;
unit = strtol(optarg, NULL, 10);
if (unit == 0 && errno != 0)
errx(EXIT_FAILURE, "Invalid unit number.");
break;
case 'v':
if (action == DESTROY)
usage();
g_gate_verbose++;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
switch (action) {
case ATTACH:
if (argc != 1)
usage();
if (unit == -1) {
fprintf(stderr, "Required unit number.\n");
usage();
}
g_gate_open_device();
path = argv[0];
g_gatel_attach();
break;
case CREATE:
if (argc != 1)
usage();
g_gate_load_module();
g_gate_open_device();
path = argv[0];
g_gatel_create();
break;
case DESTROY:
if (unit == -1) {
fprintf(stderr, "Required unit number.\n");
usage();
}
g_gate_verbose = 1;
g_gate_open_device();
g_gate_destroy(unit, force);
break;
case LIST:
g_gate_list(unit, g_gate_verbose);
break;
case UNSET:
default:
usage();
}
g_gate_close_device();
exit(EXIT_SUCCESS);
}