struct disklabel *
getdisklabel(char *s)
{
static struct disklabel lab;
struct disklabel *lp;
if (is_file) {
if (read(disk.d_fd, bootarea, BBSIZE) != BBSIZE)
err(4, "cannot read bootarea");
if (bsd_disklabel_le_dec(
bootarea + (0 /* labeloffset */ +
1 /* labelsoffset */ * sectorsize),
&lab, MAXPARTITIONS))
errx(1, "no valid label found");
lp = &lab;
return &lab;
}
if (ioctl(disk.d_fd, DIOCGDINFO, (char *)&lab) != -1)
return (&lab);
unlabeled++;
if (disktype) {
lp = getdiskbyname(disktype);
if (lp != NULL)
return (lp);
}
return (NULL);
}
static int
g_bsd_try(struct g_geom *gp, struct g_slicer *gsp, struct g_consumer *cp, int secsize, struct g_bsd_softc *ms, off_t offset)
{
int error;
u_char *buf;
struct disklabel *dl;
off_t secoff;
/*
* We need to read entire aligned sectors, and we assume that the
* disklabel does not span sectors, so one sector is enough.
*/
secoff = offset % secsize;
buf = g_read_data(cp, offset - secoff, secsize, NULL);
if (buf == NULL)
return (ENOENT);
/* Decode into our native format. */
dl = &ms->ondisk;
error = bsd_disklabel_le_dec(buf + secoff, dl, MAXPARTITIONS);
if (!error)
bcopy(buf + secoff, ms->label, LABELSIZE);
/* Remember to free the buffer g_read_data() gave us. */
g_free(buf);
ms->labeloffset = offset;
return (error);
}
/*
* Fetch disklabel for disk.
*/
static int
readlabel(int flag)
{
ssize_t nbytes;
uint32_t lba;
int f, i;
int error;
f = open(specname, O_RDONLY);
if (f < 0)
err(1, "%s", specname);
if (is_file)
get_file_parms(f);
else {
mediasize = g_mediasize(f);
secsize = g_sectorsize(f);
if (secsize < 0 || mediasize < 0)
err(4, "cannot get disk geometry");
}
if (mediasize > (off_t)0xffffffff * secsize)
errx(1,
"disks with more than 2^32-1 sectors are not supported");
(void)lseek(f, (off_t)0, SEEK_SET);
nbytes = read(f, bootarea, BBSIZE);
if (nbytes == -1)
err(4, "%s read", specname);
if (nbytes != BBSIZE)
errx(4, "couldn't read %d bytes from %s", BBSIZE, specname);
close (f);
error = bsd_disklabel_le_dec(
bootarea + (labeloffset + labelsoffset * secsize),
&lab, MAXPARTITIONS);
if (flag && error)
errx(1, "%s: no valid label found", specname);
if (is_file)
return(0);
/*
* Compensate for absolute block addressing by finding the
* smallest partition offset and if the offset of the 'c'
* partition is equal to that, subtract it from all offsets.
*/
lba = ~0;
for (i = 0; i < lab.d_npartitions; i++) {
if (lab.d_partitions[i].p_size)
lba = MIN(lba, lab.d_partitions[i].p_offset);
}
if (lba != 0 && lab.d_partitions[RAW_PART].p_offset == lba) {
for (i = 0; i < lab.d_npartitions; i++) {
if (lab.d_partitions[i].p_size)
lab.d_partitions[i].p_offset -= lba;
}
/*
* Save the offset so that we can write the label
* back with absolute block addresses.
*/
lba_offset = lba;
}
return (error);
}
/*
* Modify our slicer to match proposed disklabel, if possible.
* This is where we make sure we don't do something stupid.
*/
static int
g_bsd_modify(struct g_geom *gp, u_char *label)
{
int i, error;
struct partition *ppp;
struct g_slicer *gsp;
struct g_consumer *cp;
struct g_bsd_softc *ms;
u_int secsize, u;
off_t rawoffset, o;
struct disklabel dl;
MD5_CTX md5sum;
g_topology_assert();
gsp = gp->softc;
ms = gsp->softc;
error = bsd_disklabel_le_dec(label, &dl, MAXPARTITIONS);
if (error) {
return (error);
}
/* Get dimensions of our device. */
cp = LIST_FIRST(&gp->consumer);
secsize = cp->provider->sectorsize;
/* ... or a smaller sector size. */
if (dl.d_secsize < secsize) {
return (EINVAL);
}
/* ... or a non-multiple sector size. */
if (dl.d_secsize % secsize != 0) {
return (EINVAL);
}
/* Historical braindamage... */
rawoffset = (off_t)dl.d_partitions[RAW_PART].p_offset * dl.d_secsize;
for (i = 0; i < dl.d_npartitions; i++) {
ppp = &dl.d_partitions[i];
if (ppp->p_size == 0)
continue;
o = (off_t)ppp->p_offset * dl.d_secsize;
if (o < rawoffset)
rawoffset = 0;
}
if (rawoffset != 0 && (off_t)rawoffset != ms->mbroffset)
printf("WARNING: %s expected rawoffset %jd, found %jd\n",
gp->name,
(intmax_t)ms->mbroffset/dl.d_secsize,
(intmax_t)rawoffset/dl.d_secsize);
/* Don't munge open partitions. */
for (i = 0; i < dl.d_npartitions; i++) {
ppp = &dl.d_partitions[i];
o = (off_t)ppp->p_offset * dl.d_secsize;
if (o == 0)
o = rawoffset;
error = g_slice_config(gp, i, G_SLICE_CONFIG_CHECK,
o - rawoffset,
(off_t)ppp->p_size * dl.d_secsize,
dl.d_secsize,
"%s%c", gp->name, 'a' + i);
if (error)
return (error);
}
/* Look good, go for it... */
for (u = 0; u < gsp->nslice; u++) {
ppp = &dl.d_partitions[u];
o = (off_t)ppp->p_offset * dl.d_secsize;
if (o == 0)
o = rawoffset;
g_slice_config(gp, u, G_SLICE_CONFIG_SET,
o - rawoffset,
(off_t)ppp->p_size * dl.d_secsize,
dl.d_secsize,
"%s%c", gp->name, 'a' + u);
}
/* Update our softc */
ms->ondisk = dl;
if (label != ms->label)
bcopy(label, ms->label, LABELSIZE);
ms->rawoffset = rawoffset;
/*
* In order to avoid recursively attaching to the same
* on-disk label (it's usually visible through the 'c'
* partition) we calculate an MD5 and ask if other BSD's
* below us love that label. If they do, we don't.
*/
MD5Init(&md5sum);
MD5Update(&md5sum, ms->label, sizeof(ms->label));
MD5Final(ms->labelsum, &md5sum);
return (0);
}
/*-
* This start routine is only called for non-trivial requests, all the
* trivial ones are handled autonomously by the slice code.
* For requests we handle here, we must call the g_io_deliver() on the
* bio, and return non-zero to indicate to the slice code that we did so.
* This code executes in the "DOWN" I/O path, this means:
* * No sleeping.
* * Don't grab the topology lock.
* * Don't call biowait, g_getattr(), g_setattr() or g_read_data()
*/
static int
g_bsd_ioctl(struct g_provider *pp, u_long cmd, void *data, int fflag, struct thread *td)
{
struct g_geom *gp;
struct g_bsd_softc *ms;
struct g_slicer *gsp;
u_char *label;
int error;
gp = pp->geom;
gsp = gp->softc;
ms = gsp->softc;
switch(cmd) {
case DIOCGDINFO:
/* Return a copy of the disklabel to userland. */
bsd_disklabel_le_dec(ms->label, data, MAXPARTITIONS);
return(0);
case DIOCBSDBB: {
struct g_consumer *cp;
u_char *buf;
void *p;
int error, i;
uint64_t sum;
if (!(fflag & FWRITE))
return (EPERM);
/* The disklabel to set is the ioctl argument. */
buf = g_malloc(BBSIZE, M_WAITOK);
p = *(void **)data;
error = copyin(p, buf, BBSIZE);
if (!error) {
/* XXX: Rude, but supposedly safe */
DROP_GIANT();
g_topology_lock();
/* Validate and modify our slice instance to match. */
error = g_bsd_modify(gp, buf + ms->labeloffset);
if (!error) {
cp = LIST_FIRST(&gp->consumer);
if (ms->labeloffset == ALPHA_LABEL_OFFSET) {
sum = 0;
for (i = 0; i < 63; i++)
sum += le64dec(buf + i * 8);
le64enc(buf + 504, sum);
}
error = g_write_data(cp, 0, buf, BBSIZE);
}
g_topology_unlock();
PICKUP_GIANT();
}
g_free(buf);
return (error);
}
case DIOCSDINFO:
case DIOCWDINFO: {
if (!(fflag & FWRITE))
return (EPERM);
label = g_malloc(LABELSIZE, M_WAITOK);
/* The disklabel to set is the ioctl argument. */
bsd_disklabel_le_enc(label, data);
DROP_GIANT();
g_topology_lock();
/* Validate and modify our slice instance to match. */
error = g_bsd_modify(gp, label);
if (error == 0 && cmd == DIOCWDINFO)
error = g_bsd_writelabel(gp, NULL);
g_topology_unlock();
PICKUP_GIANT();
g_free(label);
return(error);
}
default:
return (ENOIOCTL);
}
}
