freebsd-skq/sys/geom/geom_gpt.c
phk 124977fbb6 Remove the absolute count g_access_abs() function since experience has
shown that it is not useful.

Rename the relative count g_access_rel() function to g_access(), only
the name has changed.

Change all g_access_rel() calls in our CVS tree to call g_access() instead.

Add an #ifndef BURN_BRIDGES #define of g_access_rel() for source
code compatibility.
2004-02-12 22:42:11 +00:00

228 lines
6.2 KiB
C

/*-
* Copyright (c) 2002 Marcel Moolenaar
* Copyright (c) 2002 Poul-Henning Kamp
* Copyright (c) 2002 Networks Associates Technology, Inc.
* 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.
* 3. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* 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 <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/endian.h>
#include <sys/sbuf.h>
#include <sys/uuid.h>
#include <sys/gpt.h>
#include <geom/geom.h>
#include <geom/geom_slice.h>
CTASSERT(offsetof(struct gpt_hdr, padding) == 92);
CTASSERT(sizeof(struct gpt_ent) == 128);
/*
* XXX: GEOM is not dynamic enough. We are forced to use a compile-time
* limit. The minimum number of partitions (128) as required by EFI is
* most of the time just a waste of space.
*/
#define GPT_MAX_SLICES 128
struct g_gpt_softc {
struct gpt_ent *part[GPT_MAX_SLICES];
};
static int
is_gpt_hdr(struct gpt_hdr *hdr)
{
uint32_t crc;
if (memcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)))
return (0);
crc = hdr->hdr_crc_self;
hdr->hdr_crc_self = 0;
if (crc32(hdr, hdr->hdr_size) != crc)
return (0);
hdr->hdr_crc_self = crc;
/* We're happy... */
return (1);
}
static int
g_gpt_start(struct bio *bp)
{
return (0);
}
static void
g_gpt_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
struct g_consumer *cp, struct g_provider *pp)
{
struct g_slicer *gsp = gp->softc;
struct g_gpt_softc *gs = gsp->softc;
struct uuid *uuid;
g_slice_dumpconf(sb, indent, gp, cp, pp);
if (pp != NULL) {
uuid = &gs->part[pp->index]->ent_type;
if (indent != NULL)
sbuf_printf(sb, "%s<type>", indent);
else
sbuf_printf(sb, " ty ");
sbuf_printf_uuid(sb, uuid);
if (indent != NULL)
sbuf_printf(sb, "</type>\n");
}
}
static struct g_geom *
g_gpt_taste(struct g_class *mp, struct g_provider *pp, int insist)
{
struct g_consumer *cp;
struct g_geom *gp;
struct g_gpt_softc *gs;
u_char *buf, *mbr;
struct gpt_ent *ent;
struct gpt_hdr *hdr;
u_int i, secsz, tblsz;
int error, ps;
g_trace(G_T_TOPOLOGY, "g_gpt_taste(%s,%s)", mp->name, pp->name);
g_topology_assert();
/*
* XXX: I don't like to hardcode a maximum number of slices, since
* it's wasting space most of the time and insufficient any time.
* It's easier for now...
*/
gp = g_slice_new(mp, GPT_MAX_SLICES, pp, &cp, &gs, sizeof(*gs),
g_gpt_start);
if (gp == NULL)
return (NULL);
g_topology_unlock();
gp->dumpconf = g_gpt_dumpconf;
do {
mbr = NULL;
if (gp->rank != 2 && insist == 0)
break;
secsz = cp->provider->sectorsize;
if (secsz < 512)
break;
/* XXX: we need to get the media size as well. */
/* Read both the MBR sector and the GPT sector. */
mbr = g_read_data(cp, 0, 2 * secsz, &error);
if (mbr == NULL || error != 0)
break;
#if 0
/*
* XXX: we should ignore the GPT if there's a MBR and the MBR is
* not a PMBR (Protective MBR). I believe this is what the EFI
* spec is going to say eventually (this is hearsay :-)
* Currently EFI (version 1.02) accepts and uses the GPT even
* though there's a valid MBR. We do this too, because it allows
* us to test this code without first nuking the only partitioning
* scheme we grok until this is working.
*/
if (!is_pmbr((void*)mbr))
goto out;
#endif
hdr = (void*)(mbr + secsz);
/*
* XXX: if we don't have a GPT header at LBA 1, we should check if
* there's a backup GPT at the end of the medium. If we have a valid
* backup GPT, we should restore the primary GPT and claim this lunch.
*/
if (!is_gpt_hdr(hdr))
break;
tblsz = (hdr->hdr_entries * hdr->hdr_entsz + secsz - 1) &
~(secsz - 1);
buf = g_read_data(cp, hdr->hdr_lba_table * secsz, tblsz, &error);
for (i = 0; i < hdr->hdr_entries; i++) {
struct uuid unused = GPT_ENT_TYPE_UNUSED;
struct uuid freebsd = GPT_ENT_TYPE_FREEBSD;
struct uuid tmp;
if (i >= GPT_MAX_SLICES)
break;
ent = (void*)(buf + i * hdr->hdr_entsz);
le_uuid_dec(&ent->ent_type, &tmp);
if (!memcmp(&tmp, &unused, sizeof(unused)))
continue;
/* XXX: This memory leaks */
gs->part[i] = g_malloc(hdr->hdr_entsz, M_WAITOK);
if (gs->part[i] == NULL)
break;
bcopy(ent, gs->part[i], hdr->hdr_entsz);
ps = (!memcmp(&tmp, &freebsd, sizeof(freebsd)))
? 's' : 'p';
g_topology_lock();
(void)g_slice_config(gp, i, G_SLICE_CONFIG_SET,
ent->ent_lba_start * secsz,
(1 + ent->ent_lba_end - ent->ent_lba_start) * secsz,
secsz,
"%s%c%d", gp->name, ps, i + 1);
g_topology_unlock();
}
g_free(buf);
} while (0);
if (mbr != NULL)
g_free(mbr);
g_topology_lock();
g_access(cp, -1, 0, 0);
if (LIST_EMPTY(&gp->provider)) {
g_slice_spoiled(cp);
return (NULL);
}
return (gp);
}
static struct g_class g_gpt_class = {
.name = "GPT",
.taste = g_gpt_taste,
};
DECLARE_GEOM_CLASS(g_gpt_class, g_gpt);