freebsd-dev/stand/common/vdisk.c
2022-11-30 15:30:32 -07:00

420 lines
9.5 KiB
C

/*-
* Copyright 2019 Toomas Soome <tsoome@me.com>
*
* 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 AUTHOR 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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <stand.h>
#include <stdarg.h>
#include <machine/_inttypes.h>
#include <bootstrap.h>
#include <sys/disk.h>
#include <sys/errno.h>
#include <sys/queue.h>
#include <sys/param.h>
#include <disk.h>
static int vdisk_init(void);
static int vdisk_strategy(void *, int, daddr_t, size_t, char *, size_t *);
static int vdisk_open(struct open_file *, ...);
static int vdisk_close(struct open_file *);
static int vdisk_ioctl(struct open_file *, u_long, void *);
static int vdisk_print(int);
struct devsw vdisk_dev = {
.dv_name = "vdisk",
.dv_type = DEVT_DISK,
.dv_init = vdisk_init,
.dv_strategy = vdisk_strategy,
.dv_open = vdisk_open,
.dv_close = vdisk_close,
.dv_ioctl = vdisk_ioctl,
.dv_print = vdisk_print,
.dv_cleanup = nullsys,
.dv_fmtdev = disk_fmtdev,
.dv_parsedev = disk_parsedev,
};
typedef STAILQ_HEAD(vdisk_info_list, vdisk_info) vdisk_info_list_t;
typedef struct vdisk_info
{
STAILQ_ENTRY(vdisk_info) vdisk_link; /* link in device list */
char *vdisk_path;
int vdisk_unit;
int vdisk_fd;
uint64_t vdisk_size; /* size in bytes */
uint32_t vdisk_sectorsz;
uint32_t vdisk_open; /* reference counter */
} vdisk_info_t;
static vdisk_info_list_t vdisk_list; /* list of mapped vdisks. */
static vdisk_info_t *
vdisk_get_info(struct devdesc *dev)
{
vdisk_info_t *vd;
STAILQ_FOREACH(vd, &vdisk_list, vdisk_link) {
if (vd->vdisk_unit == dev->d_unit)
return (vd);
}
return (vd);
}
COMMAND_SET(map_vdisk, "map-vdisk", "map file as virtual disk", command_mapvd);
static int
command_mapvd(int argc, char *argv[])
{
vdisk_info_t *vd, *p;
struct stat sb;
if (argc != 2) {
printf("usage: %s filename\n", argv[0]);
return (CMD_ERROR);
}
STAILQ_FOREACH(vd, &vdisk_list, vdisk_link) {
if (strcmp(vd->vdisk_path, argv[1]) == 0) {
printf("%s: file %s is already mapped as %s%d\n",
argv[0], argv[1], vdisk_dev.dv_name,
vd->vdisk_unit);
return (CMD_ERROR);
}
}
if (stat(argv[1], &sb) < 0) {
/*
* ENOSYS is really ENOENT because we did try to walk
* through devsw list to try to open this file.
*/
if (errno == ENOSYS)
errno = ENOENT;
printf("%s: stat failed: %s\n", argv[0], strerror(errno));
return (CMD_ERROR);
}
/*
* Avoid mapping small files.
*/
if (sb.st_size < 1024 * 1024) {
printf("%s: file %s is too small.\n", argv[0], argv[1]);
return (CMD_ERROR);
}
vd = calloc(1, sizeof (*vd));
if (vd == NULL) {
printf("%s: out of memory\n", argv[0]);
return (CMD_ERROR);
}
vd->vdisk_path = strdup(argv[1]);
if (vd->vdisk_path == NULL) {
free (vd);
printf("%s: out of memory\n", argv[0]);
return (CMD_ERROR);
}
vd->vdisk_fd = open(vd->vdisk_path, O_RDONLY);
if (vd->vdisk_fd < 0) {
printf("%s: open failed: %s\n", argv[0], strerror(errno));
free(vd->vdisk_path);
free(vd);
return (CMD_ERROR);
}
vd->vdisk_size = sb.st_size;
vd->vdisk_sectorsz = DEV_BSIZE;
STAILQ_FOREACH(p, &vdisk_list, vdisk_link) {
vdisk_info_t *n;
if (p->vdisk_unit == vd->vdisk_unit) {
vd->vdisk_unit++;
continue;
}
n = STAILQ_NEXT(p, vdisk_link);
if (p->vdisk_unit < vd->vdisk_unit) {
if (n == NULL) {
/* p is last elem */
STAILQ_INSERT_TAIL(&vdisk_list, vd, vdisk_link);
break;
}
if (n->vdisk_unit > vd->vdisk_unit) {
/* p < vd < n */
STAILQ_INSERT_AFTER(&vdisk_list, p, vd,
vdisk_link);
break;
}
/* else n < vd or n == vd */
vd->vdisk_unit++;
continue;
}
/* p > vd only if p is the first element */
STAILQ_INSERT_HEAD(&vdisk_list, vd, vdisk_link);
break;
}
/* if the list was empty or contiguous */
if (p == NULL)
STAILQ_INSERT_TAIL(&vdisk_list, vd, vdisk_link);
printf("%s: file %s is mapped as %s%d\n", argv[0], vd->vdisk_path,
vdisk_dev.dv_name, vd->vdisk_unit);
return (CMD_OK);
}
COMMAND_SET(unmap_vdisk, "unmap-vdisk", "unmap virtual disk", command_unmapvd);
/*
* unmap-vdisk vdiskX
*/
static int
command_unmapvd(int argc, char *argv[])
{
size_t len;
vdisk_info_t *vd;
long unit;
char *end;
if (argc != 2) {
printf("usage: %s %sN\n", argv[0], vdisk_dev.dv_name);
return (CMD_ERROR);
}
len = strlen(vdisk_dev.dv_name);
if (strncmp(vdisk_dev.dv_name, argv[1], len) != 0) {
printf("%s: unknown device %s\n", argv[0], argv[1]);
return (CMD_ERROR);
}
errno = 0;
unit = strtol(argv[1] + len, &end, 10);
if (errno != 0 || (*end != '\0' && strcmp(end, ":") != 0)) {
printf("%s: unknown device %s\n", argv[0], argv[1]);
return (CMD_ERROR);
}
STAILQ_FOREACH(vd, &vdisk_list, vdisk_link) {
if (vd->vdisk_unit == unit)
break;
}
if (vd == NULL) {
printf("%s: unknown device %s\n", argv[0], argv[1]);
return (CMD_ERROR);
}
if (vd->vdisk_open != 0) {
printf("%s: %s is in use, unable to unmap.\n",
argv[0], argv[1]);
return (CMD_ERROR);
}
STAILQ_REMOVE(&vdisk_list, vd, vdisk_info, vdisk_link);
(void) close(vd->vdisk_fd);
printf("%s (%s) unmapped\n", argv[1], vd->vdisk_path);
free(vd->vdisk_path);
free(vd);
return (CMD_OK);
}
static int
vdisk_init(void)
{
STAILQ_INIT(&vdisk_list);
return (0);
}
static int
vdisk_strategy(void *devdata, int rw, daddr_t blk, size_t size,
char *buf, size_t *rsize)
{
struct disk_devdesc *dev;
vdisk_info_t *vd;
ssize_t rv;
dev = devdata;
if (dev == NULL)
return (EINVAL);
vd = vdisk_get_info((struct devdesc *)dev);
if (vd == NULL)
return (EINVAL);
if (size == 0 || (size % 512) != 0)
return (EIO);
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
daddr_t offset;
offset = dev->d_offset * vd->vdisk_sectorsz;
offset /= 512;
blk += offset;
}
if (lseek(vd->vdisk_fd, blk << 9, SEEK_SET) == -1)
return (EIO);
errno = 0;
switch (rw & F_MASK) {
case F_READ:
rv = read(vd->vdisk_fd, buf, size);
break;
case F_WRITE:
rv = write(vd->vdisk_fd, buf, size);
break;
default:
return (ENOSYS);
}
if (errno == 0 && rsize != NULL) {
*rsize = rv;
}
return (errno);
}
static int
vdisk_open(struct open_file *f, ...)
{
va_list args;
struct disk_devdesc *dev;
vdisk_info_t *vd;
int rc = 0;
va_start(args, f);
dev = va_arg(args, struct disk_devdesc *);
va_end(args);
if (dev == NULL)
return (EINVAL);
vd = vdisk_get_info((struct devdesc *)dev);
if (vd == NULL)
return (EINVAL);
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
rc = disk_open(dev, vd->vdisk_size, vd->vdisk_sectorsz);
}
if (rc == 0)
vd->vdisk_open++;
return (rc);
}
static int
vdisk_close(struct open_file *f)
{
struct disk_devdesc *dev;
vdisk_info_t *vd;
dev = (struct disk_devdesc *)(f->f_devdata);
if (dev == NULL)
return (EINVAL);
vd = vdisk_get_info((struct devdesc *)dev);
if (vd == NULL)
return (EINVAL);
vd->vdisk_open--;
if (dev->dd.d_dev->dv_type == DEVT_DISK)
return (disk_close(dev));
return (0);
}
static int
vdisk_ioctl(struct open_file *f, u_long cmd, void *data)
{
struct disk_devdesc *dev;
vdisk_info_t *vd;
int rc;
dev = (struct disk_devdesc *)(f->f_devdata);
if (dev == NULL)
return (EINVAL);
vd = vdisk_get_info((struct devdesc *)dev);
if (vd == NULL)
return (EINVAL);
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
rc = disk_ioctl(dev, cmd, data);
if (rc != ENOTTY)
return (rc);
}
switch (cmd) {
case DIOCGSECTORSIZE:
*(u_int *)data = vd->vdisk_sectorsz;
break;
case DIOCGMEDIASIZE:
*(uint64_t *)data = vd->vdisk_size;
break;
default:
return (ENOTTY);
}
return (0);
}
static int
vdisk_print(int verbose)
{
int ret = 0;
vdisk_info_t *vd;
char line[80];
if (STAILQ_EMPTY(&vdisk_list))
return (ret);
printf("%s devices:", vdisk_dev.dv_name);
if ((ret = pager_output("\n")) != 0)
return (ret);
STAILQ_FOREACH(vd, &vdisk_list, vdisk_link) {
struct disk_devdesc vd_dev;
if (verbose) {
printf(" %s", vd->vdisk_path);
if ((ret = pager_output("\n")) != 0)
break;
}
snprintf(line, sizeof(line),
" %s%d", vdisk_dev.dv_name, vd->vdisk_unit);
printf("%s: %" PRIu64 " X %u blocks", line,
vd->vdisk_size / vd->vdisk_sectorsz,
vd->vdisk_sectorsz);
if ((ret = pager_output("\n")) != 0)
break;
vd_dev.dd.d_dev = &vdisk_dev;
vd_dev.dd.d_unit = vd->vdisk_unit;
vd_dev.d_slice = -1;
vd_dev.d_partition = -1;
ret = disk_open(&vd_dev, vd->vdisk_size, vd->vdisk_sectorsz);
if (ret == 0) {
ret = disk_print(&vd_dev, line, verbose);
disk_close(&vd_dev);
if (ret != 0)
break;
} else {
ret = 0;
}
}
return (ret);
}